Older Drivers

Description of Strategies

Objectives

The objectives for accommodating older drivers on the roadway and sustaining their proficiency are to:

  • Plan for an aging population,
  • Improve the roadway and driving environment to better accommodate older drivers- special needs,
  • Identify older drivers at increased risk of crashing and intervene,
  • Improve the older adults' competency in the general driving population, and
  • Reduce the risk of injury and death to older drivers and passengers involved in crashes.

Exhibit V-1 presents these objectives and related strategies for sustaining older drivers' proficiency. The following section explains the types of strategies available—either proven (P), tried (T) or experimental (E). In the case of older drivers, most identified strategies fall into the “tried” category, due to the lack of properly designed evaluations.

EXHIBIT V-1
Objectives and Strategies for Sustaining Proficiency in Older Drivers

Objectives

Strategies

3.1 A Plan for an aging population

3.1 A1 Establish a broad-based coalition to plan for addressing older adults' transportation needs (T)

3.1.B Improve the roadway and driving environment to better accommodate older drivers’ special needs

3.1 B1 Provide advance warning signs (T)

3.1 B2 Provide advance guide signs and street name signs (T)

3.1 B3 Increase size and letter height of roadway signs (T)

3.1 B4 Provide all-red clearance intervals at signalized intersections (T)

3.1 B5 Provide more protected left-turn signal phases at high-volume intersections (T)

3.1 B6 Provide offset left-turn lanes at intersections (T)

3.1 B7 Improve lighting at intersections, horizontal curves, and railroad grade crossings (T)

3.1 B8 Improve roadway delineation (T)

3.1 B9 Replace painted channelization with raised channelization (P)

3.1 B10 Reduce intersection skew angle (T)

3.1 B11 Improve traffic control at work zones (T)

3.1.C Identify older drivers at increased risk of crashing and intervene

3.1 C1 Strengthen the role of medical advisory boards (T)

3.1 C2 Update procedures for assessing medical fitness to drive (P)

3.1 C3 Encourage external reporting of impaired drivers to licensing authorities (T)

3.1 C4 Provide remedial assistance to help functionally impaired older drivers (T)

3.1 D Improve the driving competency of older adults in the general driving population

3.1 D1 Establish resource centers within communities to promote safe mobility choices (T)

3.1 D2 Provide educational and training opportunities to the general older driver population (T)

3.1 E Reduce the risk of injury and death to older drivers and passengers involved in crashes

3.1 E1 Increase seatbelt use by older drivers and passengers (P)

Explanation of Strategy Types

The strategies in this guide were identified from a number of sources, including a literature review, contact with state and local agencies throughout the United States, and federal programs. Some of the strategies are widely used, while others are used at a state or even a local level. Some have been subjected to well-designed evaluations to prove their effectiveness. However, it was found that many strategies have not been adequately evaluated, including some widely used strategies.

The implication of the widely varying experience with these strategies, as well as the range of knowledge about their effectiveness, is that the reader should be cautious before adopting a particular strategy for implementation. To assist, the strategies have been classified into three types, each identified by letter throughout the guide:

  • Proven (P): Those strategies that have been used in one or more locations and subjected to properly designed evaluations that show it to be effective. These strategies may be employed with a good degree of confidence, but any application can lead to results that vary significantly from those found in previous evaluations. The attributes of the provided strategies will help the user to judge the most appropriate for his or her particular situation.
  • Tried (T): Those strategies that have been implemented in a number of locations and that may even be accepted as standards or standard approaches, but that lack found valid evaluations. These strategies, while in frequent or even general use, should be applied with caution, carefully considering the attributes cited in the guide and relating them to the specific conditions for which they are being considered. Implementation can proceed with some degree of assurance that a negative impact on safety is unlikely and that a positive one is very likely. It is intended that appropriate evaluations can be conducted as the experiences implementing these strategies continue under the AASHTO Strategic Highway Safety Plan (SHSP) initiative. In this matter, effectiveness information can be accumulated to provide the user with better estimating power and to upgrade the strategy to “proven.”
  • Experimental (E): Those strategies that have been suggested and found sufficiently promising that at least one agency has considered trying them on a small scale in at least one location. These strategies should be considered only after the others have proven inappropriate or unfeasible. Even where they are considered, their implementation should initially occur using a very controlled and limited pilot study that includes a properly designed evaluation component. Broader implementation should be considered only after careful testing and evaluations show the strategy to be effective. It is intended that as the experiences of such pilot tests are accumulated from various state and local agencies, the aggregate experience can be used to further detail the attributes of this type of strategy so that it can be upgraded to “proven.”

Related Strategies for Creating a Truly Comprehensive Approach

The strategies listed above are considered unique to problems associated with older drivers. However, to create a truly comprehensive approach to the highway safety problems associated with older drivers, related strategies should be included as candidates in any program planning process. These are five types:

  • Older Driver Organizations and Involvement—Many highway safety programs can be effectively enhanced with input from older drivers and their representative organizations.

    Older drivers can also provide direct input into highway agencies as focus groups or formal organizations. Since older drivers know best the types of problems they encounter in the driving environment, they could be significant assets to a highway agency’s overall safety program. As additional guides are completed for the AASHTO Strategic Highway Safety Plan, they may address the details regarding the implementation of public involvement or focus groups.

  • Consideration of Older Drivers in the Planning Process—Most of the strategies in the AASHTO plan are intended for application at locations with identified safety problems. When taking a comprehensive approach, safety problems can often be avoided prior to a project’s construction. Specifically, design criteria that favor older drivers (e.g., righthand exits on freeways and longer acceleration lanes) should be considered in the planning process. Thus, many highway safety programs can be effectively enhanced with consideration of older drivers in the planning process. As additional guides are completed for the AASHTO Strategic Highway Safety Plan, they may address the consideration of safety in the planning process.
  • Strategies Directed at Implementing and Improving the Safety Management System— The highway safety system is fundamental to success. There should be in place a sound organizational structure and an effective decision support system, as well as infrastructure of laws, policies, etc., to monitor, control, direct, and administer a comprehensive approach to highway safety. It is important that a comprehensive program not be limited to one jurisdiction, such as a state DOT. Local agencies often oversee most of the road system and its related safety problems. They also know best what the problems are. As additional guides are completed for the AASHTO Strategic Highway Safety Plan, they may address the details regarding the design and implementation of strategies for safety management systems.
  • Strategies to Improve Emergency Medical and Trauma System Services—Treatment of injured parties at highway crashes can have a significant impact on the severity level and length of time that an individual spends in treatment. This is especially true when it comes to timely and appropriate treatment of older or severely injured persons. Thus, a basic part of a highway safety infrastructure is a well-based and comprehensive emergency care program. While the types of strategies included here are often thought of as simply support services, they can be critical to the success of a comprehensive highway safety program. Therefore, for this emphasis area especially, an effort should be made to determine if there are improvements that can be made to this aspect of the system, especially for programs focused on location (e.g., corridors) or area-specific (e.g., rural areas) issues. As additional guides are completed for the AASHTO plan, they may address the details regarding the design and implementation of emergency medical systems strategies.
  • Strategies Detailed in Other Emphasis Area Guides—Any program targeted at the safety problem covered in this emphasis area should consider the inclusion of other applicable strategies covered in the crash-intervention guides for the following:

Objective 3.1 A—Plan for an Aging Population

Strategy 3.1 A1: Establish a Broad-Based Coalition to Plan for Addressing the Older Adults’ Transportation Needs (T)

General Description

In response to this dramatic population shift, the U.S. Department of Transportation recently guided efforts to develop a comprehensive plan for safe mobility for a maturing society (U.S. DOT, 2003). The plan evolved from a series of regional forums, focus groups, conferences, and stakeholder roundtables held over a period of several years. It articulated the following vision for America’s future transportation system:

A transportation system that offers safe mobility to all people and allows older persons to remain independent and to age in place. Investments in highway and pedestrian infrastructure and public transportation services support independence. Medical and social service communities, transportation managers, motor vehicle administrators, and caregivers work together to extend safe driving and to offer other convenient and affordable transportation options when driving and walking must be curtailed. Public and private organizations form new partnerships to enable all citizens to enjoy safe mobility for life. (U.S. DOT, 2003)

The U.S. DOT document outlines specific strategies in a broad range of areas that encompass the roadway infrastructure, walkways, vehicle design, specialized vehicle systems, driver competency, public transportation services, public education, and research. The document also calls for the development of action plans at the state and local levels for addressing the safety and mobility needs of the older population.

Like the national plan, these state and local action plans need to reflect the input of a broad consortium of governmental agencies and organizations and interests in the private sector. Although state transportation departments can lead the effort, they need to create partnerships with other departments and agencies at the state, regional, and local levels. Potential collaborators include the state office on aging, area agencies on aging, law enforcement officials, state and local planners, transportation service providers, social service agencies, the medical and public health communities, the American Association of Motor Vehicle Administrators (http://www.aamva.org/drivers/drv_AgingDrivers.asp), the American Automobile Association (AAA) Foundation for Traffic Safety (http://www.aaafoundation.org/), the American Association of Retired Persons (AARP) (http://www.aarp.org/drive/), other advocacy groups, and seniors themselves. All must share in the responsibility of developing, implementing, and evaluating a comprehensive action plan to address the safety and mobility needs of the growing elderly population.

A number of states and metropolitan planning organizations have already established task forces or consortia to address the needs of older adults. The states include Arizona, California, Florida, Iowa, Maryland, and Michigan. Several of these states have also developed long-range action plans.

  • The Southeast Michigan Council of Governments (SEMCOG) produced a comprehensive action plan. “Elderly Mobility and Safety: Final Plan of Action” is available on the SEMCOG website (see Appendix 2). It was developed by the Iowa Older Driver Task Force, which also conducted focus groups to develop input (see Appendix 3).
  • A portion of the Iowa Traffic Safety Toolbox addressing older driver safety appears as Appendix 4.

Each of these plans was developed by a coalition of partners dedicated to addressing the safety and mobility needs of older adults. Coalitions have proven effective in addressing other highway safety concerns as well, as evidenced by Safe Community programs across the country and ongoing efforts to reduce underage drinking. Guidance on building effective coalitions is available on the National Highway Traffic Safety Administration (NHTSA) Web site at http://www.nhtsa.dot.gov/people/injury/alcohol/Community%20Guides%20HTML/Book1_CoalitionBldg.html and http://www.nhtsa.dot.gov/people/outreach/safesobr/12qp/coalition.html.

EXHIBIT V-2
Strategy Attributes for Establishing a Coalition and Planning for Older Adult Transportation Needs (T)

Attribute Description
Technical Attributes
Target The target audience for this strategy is state departments of transportation, metropolitan planning organizations (MPOs), and local transportation and planning offices. Although other agencies and organizations should be active participants in this strategy, transportation agencies should assume primary responsibility for formulating the coalition and plan.
Expected Effectiveness Although the plans and activities of coalition groups have not been formally evaluated, they have generated a number of positive accomplishments. However, it is still too early to judge the impact of such plans, especially in terms of reductions in older driver fatalities. Formal evaluations are needed, but it may be unfeasible to determine the direct linkage between this type of support effort and the bottom-line safety measure. Process measures, especially measures of resulting activity (i.e., the intermediate impact on the size and type of highway-safety-oriented programs implemented) of the coalition may be more appropriate.
Keys to Success Keys to success include commitment by the state department of transportation or some other agency to lead the effort; high level, “top down” support from key stakeholders; and the ability to bring together and work with a broad cross section of individuals from other departments, agencies, and organizations. Typically, a highlevel “champion” is needed within the primary agency to ensure that the process is carried through and has the proper support. The involvement and active participation of a wide array of stakeholders, representing both the public and private sectors, is also a key to success.
Potential Difficulties The type of broad-based consortia required for this strategy may be unfamiliar to some state transportation departments, and securing widespread involvement and participation can be a challenge.
Appropriate Measures and Data Process measures of program effectiveness include the number of groups participating in the consortium, whether key stakeholders are represented, the activity level of the group, and actual adoption of practices and procedures of the targeted agencies (e.g., policies adopted, procedures altered, programs implemented).

Effectiveness is to be ultimately measured by comparing the crash experience of groups affected by the programs, with either control populations or those not affected.
Associated Needs The primary need is for support of the consortium from the upper management in the transportation agency that takes the lead. This would include achieving commitment from other agencies, at the level of upper management, to be a continuing part of the coalition. Although consortium delegates, or their organizations, can be expected to contribute their time to the effort, funding for travel reimbursement and provision of support staff is also desirable.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues A framework is needed that supports collaborative efforts by various governmental agencies. Some of the recommendations may require collaboration between government agencies or between government agencies and the private sector. Some may also require changes in policy.
Issues Affecting Implementation Time Upper management of the lead agency must provide support to an individual or individuals to help establish and lead the consortium. This is not considered to be a short-term undertaking, and various working groups of the consortium may want to maintain ongoing working relationships. The overall timeframe for the effort will be affected by what is or is not already in place at the time, as well as the goals that the consortium sets for itself.
Costs Involved Costs should be fairly minimal, primarily involving personnel time for meetings, time for support staff, and travel for participating task force members.
Training and Other Personnel Needs None identified.
Legislative Needs Legislative backing can be helpful in securing adequate support and participation from key governmental agencies.
Other Key Attributes
None identified.


Information on Agencies or Organizations Currently Implementing the Strategy

As noted above, a number of states and MPOs have already established task forces or consortia to address the needs of older adults. They include Arizona, California, Florida, Iowa, Maryland, and Michigan. In addition, comprehensive plans are now in place in many of these states. Information on the many activities underway in Florida can be obtained by contacting Selma Sauls, Florida Department of Highway Safety and Motor Vehicles, Division of Driver Licenses, 850-487-0867. The Maryland Research Consortium activities are documented in the final reports for the Model Driver Screening and Evaluation Program project (see http://www.nhtsa.dot.gov/people/injury/olddrive/modeldriver/). Appendix 1 of the Volume II report contains a table of the Maryland Consortium’s goals, objectives and action steps.

Objective 3.1 B—Improve the Roadway and Driving Environment to Better Accommodate Older Drivers’ Special Needs

Strategy 3.1 B1: Provide Advance Warning Signs (T)

General Description

Advance warning signs inform drivers of existing or potentially hazardous conditions on or adjacent to the roadways. Such signs require caution on the part of the driver and may call for a reduction in speed or other maneuver. Advance warning signs should be considered for the following situations:

  1. Where speed may have to be reduced—curves, grades, bumps, dips, and approaches to STOP and YIELD signs, to signals, and to railroad grade crossings.
  2. Where lateral placement may have to be modified—narrow roadways, beginnings and ends of medians, channelizing islands, reduction in the number of lanes, no passing zones, and “two-way traffic ahead” warnings.
  3. Potential conflict zones—intersections, merging areas, pedestrian and bicycle crossings, and school zones.
  4. Construction and maintenance zones.
  5. Miscellaneous—dead end streets, restricted clearances, and areas frequented by wild animals or subject to falling rocks, icing, or flooding.

Guide signs are recommended in these situations for all drivers. However, due to the slower information processing and reaction time of older drivers, it is particularly important that advance warning signs be placed well in advance of the potential hazard to provide older drivers with extra time to respond appropriately.

EXHIBIT V-3
Strategy Attributes for Providing Advance Warning Signs (T)

Attribute Description
Technical Attributes
Target The targets of this strategy are roadway features that may not be anticipated or easily recognized by older adults with visual, cognitive, and/or psychomotor impairments.
Expected Effectiveness The effectiveness of this strategy in reducing crashes has not been satisfactorily quantified. Nevertheless, there is a general consensus that advanced warning signs can help reduce confusion and perception/reaction time at existing or potentially hazardous conditions on or adjacent to the roadways.

Further research to develop safety effectiveness measures for this strategy is desirable.
Keys to Success A key to success in applying this strategy is to identify appropriate locations and/or situations that would benefit from advance warning signs. The location is important because advance warning signs that are placed either too far or not far enough in advance of a potentially hazardous condition will make the signing less effective. Table 2C-4 in the MUTCD (http://mutcd.fhwa.dot.gov/kno-millennium.htm) presents guidelines for advance placement of warning signs relative to the type of potentially hazardous condition and the posted or 85th percentile speed on the roadway. Advance warning signs should be applied with consistency and uniformity. Engineering judgment should, where possible, be accompanied by a human factor assessment of the need for advance warning signs.

Another key to success is the ability and commitment of the highway agency to adequately maintain the signs. Regular cleaning of signs can improve the retroreflectivity by up to 30 percent.

Another key to success is the size of and letter height on advance warning signs. Refer to Strategy 3.1 B3 for further information on this issue.
Potential Difficulties Care should be taken not to overuse advance warning signs and to place appropriate distance between the different signs. The objective is not to overload the driver with so much information that the signs become the cause of confusion and speed reduction results. Agencies should strive to use advance warning signs only where a special problem or circumstance indicates the need and to maintain a certain consistency and uniformity to the application.
Appropriate Measures and Data Key process measures are the number and type of advance warning signs placed and the number of locations for which advanced signing is provided.

Crash frequency and severity, by type, are key safety effectiveness measures. Both total crashes and crash types (by driver age group) potentially affected by the use of advance warning signs should be analyzed separately. Driver behavior (e.g., erratic maneuvers, near misses, and conflicts) may be used as surrogate safety measures. Traffic volume data are needed to represent exposure.
Associated Needs None identified.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Nearly any highway agency can participate in the implementation of this strategy. State highway agencies that implement this strategy may serve as a role model for local agencies, even to the extent of developing a “best practices” manual for local agencies to use in making decisions about providing advance warning signs.

A general policy may need to be developed to provide the foundation for a long-term and consistent commitment to the strategy.
Issues Affecting Implementation Time This strategy does not require a long development process. Signing improvements can typically be implemented in 3 months or less. Policy development and adoption, if required, could extend the implementation period.
Costs Involved Costs for implementing this strategy are nominal. An agency’s maintenance costs may increase.
Training and Other Personnel Needs Training regarding use of this strategy should be provided in highway agency training courses concerning the use of traffic control devices, including the special needs of older drivers.
Legislative Needs None identified.
Compatibility of Different Strategies This strategy can be used in conjunction with most other strategies for improving safety.
Other Key Attributes
None identified.


Information on Agencies or Organizations Currently Implementing the Strategy

Many highway agencies, including the Atlanta and Tyler Districts of TxDOT, provide advance warning signs in advance of signalized intersections (see Exhibits V-4 and V-5).

EXHIBIT V-4
Advance Warning Sign in Advance of a Signalized Intersection (Atlanta District, TxDOT)

EXHIBIT V-5
Advance Warning Sign in Advance of a Signalized Intersection (Atlanta District, TxDOT)

EXHIBIT V-6
Advance Warning Sign in Advance of a Horizontal Curve (Atlanta District, TxDOT)

Strategy 3.1 B2: Provide Advance Guide Signs and Street Name Signs (T)

General Description

Guide signs inform drivers about their location and route, direct drivers to various destinations, identify roadside services and points of interest, and furnish other helpful information. Guide signs include signs for route identification, destination, interchange, and other information. Providing guide signs well in advance of a roadway decision point gives drivers additional time to make necessary lane changes and route selection decisions. This additional time is especially important for older drivers, who generally take longer to process and react to information on a sign.

Use of a supplemental street name sign with an advance warning crossroad, side road, or T-intersection sign provides older drivers with the benefit of additional decision and maneuvering time, especially if a change of one or more lanes is required prior to reaching the intersection. Older drivers have been known to exhibit excessive vehicle-braking behavior when a signal or road sign is seen. In fact, researchers have observed older drivers who stopped suddenly at or before an intersection to read street signs. This is unsafe, confusing, and disruptive to traffic following a driver who brakes for no apparent reason.

Furthermore, older drivers participating in focus groups have stated that they need more advance notice regarding upcoming cross streets to have time to decide where to turn. Providing sufficient time to allow motorists to make appropriate turning movements when approaching cross streets can improve safety and reduce congestion. Consistent street signing across political jurisdictions is also important.

EXHIBIT V-7
Strategy Attributes for Providing Advance Guide Signs and Street Name Signs

Attribute Description
Technical Attributes
Target This strategy targets roadway features that older adults may not anticipate or easily recognize because of reduced or impaired visual, cognitive, and/or psychomotor skills.
Expected Effectiveness This strategy’s effectiveness in reducing crashes has not been satisfactorily quantified.

FHWA is currently funding demonstration projects to evaluate its effectiveness. Further research is desirable to quantify the safety effectiveness of these techniques.
Keys to Success A key to success in applying this strategy is to identify appropriate locations and/or situations that would benefit from advanced guide signs and street name signs. They should be applied uniformly and consistently. Engineering judgment should, where possible, be accompanied by a human factor assessment of the need for such signs. Where advance guide signs are placed upstream of interchanges, adding lane designations to the signs may enhance their effectiveness.

Another key to success is the ability and commitment of the highway agency to adequately maintain the signs. Regular sign cleaning can improve the retroreflectivity by up to 30 percent.
Potential Difficulties Care should be taken not to overuse advance guide signs and street name signs and not to inappropriately space them, as either action may cause information overload, confusion, and speed reduction.
Appropriate Measures and Data A key process measure is the number of locations where advanced guide signs and street name signs were improved.

Crash frequency and severity, by type (by age group), are key safety effectiveness measures. Driver behavior (e.g., erratic maneuvers, near misses, or conflicts) may be used as surrogate safety measures. Traffic volume data are needed to represent exposure.
Associated Needs None identified.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Nearly any highway agency can implement this strategy. A general policy may need to be developed to provide the foundation for a long-term and consistent commitment to the strategy.
Issues Affecting Implementation Time This strategy does not require a long development process. Signing improvements can typically be implemented within 3 months. Policy development and adoption, if required, could extend the implementation period.
Costs Involved Costs for implementing this strategy are nominal. An agency’s maintenance costs may increase.

This strategy may be implemented first at higher-priority cross streets (e.g., highspeed arterials) and then at others as funds become available.
Training and Other Personnel Needs Older drivers’ special needs should be included in training courses concerning the use of traffic control devices.
Legislative Needs None identified.
Compatibility of Different Strategies This strategy can be used in conjunction with most other strategies for improving safety.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing the Strategy

In addition to providing advance street name signs (see Exhibit V-8), the Atlanta and Tyler Districts of TxDOT provide internally lit street name signs at many intersections (see Exhibit V-9).

EXHIBIT V-8
Advance Street Name Sign (Tyler District, TxDOT)

EXHIBIT V-9
Internally Lit Street Name Sign at Intersection (Atlanta District, TxDOT)

Strategy 3.1 B3: Increase Size and Letter Height of Roadway Signs (T)

General Description

As visual acuity declines with age, so does the ability to read roadway signs. Older drivers participating in focus groups and completing questionnaires for traffic safety researchers over the past decade have consistently stated that larger street signs with bigger lettering and standardization of sign placement overhead would make driving easier. In a laboratory simulation study, Staplin et al. (1990) found that older drivers, compared with a group of younger drivers, required larger letter sizes to discern a message on a guide sign. Increasing the letter height on roadway signs would better accommodate older drivers’ reduced visual acuity.

More details regarding specific recommendations for letter height and size may be found in Appendix 5. For more information on providing larger regulatory and warning signs, see the companion guide on crashes at unsignalized intersections.

EXHIBIT V-10
Strategy Attributes for Increasing the Size and Letter Height of Roadway Signs (T)

Attribute Description
Technical Attributes
Target This strategy targets roadway features that older drivers may not anticipate or easily recognize due to reduced or impaired visual, cognitive, and/or psychomotor skills.
Expected Effectiveness This strategy’s effectiveness in reducing crashes has not been satisfactorily quantified.

Further research to quantify the safety effectiveness of these techniques is desirable.
Keys to Success A key to success in applying this strategy is to select a combination of roadway signing techniques appropriate to conditions on the roadway. Engineering judgment should, where possible, be accompanied by a human factor assessment of the need to change letter heights on the signs.

Another key to success is the highway agency’s ability and commitment to adequately maintain the signs. Cleaning signs regularly can improve the retroreflectivity by up to 30 percent.
Potential Difficulties Care should be taken not to overuse traffic signing, as it is likely that drivers will become accustomed to their presence and fail to respond as desired or intended. Agencies should strive to use special signing only where a specific problem or circumstance indicates the need.
Appropriate Measures and Data A key process measure is the number of locations where larger signs and increased letter sizes were used.

Crash frequency and severity, by type (by age group), are key safety effectiveness measures. Both total crashes and crash types potentially affected by the use of larger signs and lettering should be analyzed separately. Driver behavior (e.g., erratic maneuvers, near misses, or conflicts) may be used as surrogate safety measures. Traffic volume data are needed to represent exposure.
Associated Needs None identified.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Nearly any highway agency can implement this strategy. A general policy may need to be developed to provide the foundation for a long-term and consistent commitment to the strategy.
Issues Affecting Implementation Time This strategy does not require a long development process. Signing improvements can typically be implemented within 3 months. Policy development and adoption, if required, could extend the implementation period.

One method of implementation is to incorporate larger signs as part of routine maintenance. As part of the rotation schedule, smaller signs can be replaced with larger signs. In this case, the implementation time will be whatever the cycle time is to replace all signs under an agency’s regular rotation schedule.
Costs Involved Costs for implementing this strategy are nominal. An agency’s maintenance costs may increase.
Training and Other Personnel Needs Training regarding use of this strategy should be provided in highway agency training courses concerning the use of traffic control devices, especially regarding the needs of older drivers.
Legislative Needs None identified.
Compatibility of Different Strategies This strategy can be used in conjunction with most other strategies for improving safety.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing the Strategy

Phoenix, Arizona, has been using “jumbo” street name signs at intersections since 1973 because of its large older driver population. These signs are 400 mm (16 in.) high with capital lettering at 200 mm (8 in.), in contrast with the MUTCD-recommended standard sign size of 150 mm (6 in.) high and 100-mm (4-in.) lettering (“Phoenix Street Signs Big, Legible,” Rural and Urban Roads, Vol. 11, No. 5, 1973).

TxDOT’s Atlanta and Tyler Districts use “expressway size” speed limit signs on conventional highways (see Exhibit V-11). Their speed limit signs are typically 36 × 48 in., whereas the MUTCD-recommended standard size is 24 × 30 in.

The minimum STOP sign size, according to the MUTCD, is 24 × 24 in. However, the MUTCD recommends a STOP sign size of 30 × 30 in. for conventional roadways. To accommodate older drivers’ declining visual acuity, the Florida DOT has decided to replace all 24 × 24 or 30 × 30 in. STOP signs with 48 × 48 in. signs. No effectiveness measures have been provided.

EXHIBIT V-11
Large (36 × 48 in.) Speed Limit Sign (Atlanta District, TxDOT)

Strategy 3.1 B4: Provide All-Red Clearance Interval at Signalized Intersections (T)

General Description

To accommodate older drivers’ slower perception and reaction, the Older Driver Handbook recommends that an all-red clearance interval be consistently implemented at signalized intersections (Staplin et al., 1998). The recommendation is based on two studies that evaluated the assumptions behind the perception-reaction time used to calculate the change intervals between phases.

Tarawneh (1991) examined previous research on driver information processing to determine the best estimator of perception-reaction time for older drivers. It was determined that a signal change at an intersection is among the most extreme, in terms of both the informationprocessing demand and subjective feelings of stress, experienced by many older drivers. Therefore, Tarawneh called for an increase in the perception-reaction time value used to calculate the length of yellow interval from 1 to 1.5 seconds to accommodate older drivers. Knoblauch et al. (1995) compared the decision-response times and deceleration characteristics of older drivers with those of younger drivers at the onset of the yellow signal phase. The study found no significant differences in 85th percentile decision-response times between younger and older drivers when subjects were close to the signal. However, when subjects were farther from the signal at the onset of the yellow phase, older drivers had significantly longer decision-response times than younger ones had. Knoblauch et al. concluded that no change in the yellow phase timing was required to accommodate older drivers.

Although the two studies above present conflicting conclusions, both studies recognize a higher perception-reaction time for older drivers. The Older Driver Handbook recommends retaining the 1-second perception-reaction time value for calculating the yellow change interval, but also providing an all-red clearance interval. The all-red clearance interval would provide sufficient time for older drivers to clear an intersection before conflicting movements begin.

Details regarding an ITE recommendation for calculating the all-red clearance interval may be found in Appendix 6.

It is important to note that signal-timing changes might affect the operational aspects of signalized intersections. The increase in clearance time may increase delay and/or affect signal progression, thereby reducing the intersection’s level of service. Agencies will have to consider the potential tradeoffs before making a final decision. The TRB Highway Capacity Manual (HCM) can be used to determine effects on delay (http://www.a3a10.gati.org/).

For more information on providing all-red clearance intervals at signalized intersections, see Strategy 17.2 A2 in the companion guide on crashes at signalized intersections.

Information on Agencies or Organizations Currently Implementing the Strategy

The Wisconsin Department of Transportation implements a 4- to 5-second all-red clearance interval at signalized intersections to accommodate all drivers, including older ones.

Strategy 3.1 B5: Provide More Protected Left-Turn Signal Phases at High-Volume Intersections (P)

General Description

Accident analyses have shown that older drivers have more left-turn accidents at signalized intersections; the principal violations are failing to yield right-of-way and disregarding the signal. In addition, research has shown that the relative accident involvement ratios for older drivers were higher at signalized intersections with permitted left-turn phases than at those with protected left-turn phases.

One of the problems with permitted left-turn phases is the difficulty older drivers may have in determining acceptable gaps and maneuvering through traffic streams when there is no protective phase. Older drivers may also have difficulty understanding the rules for making permitted left turns. If the signals and markings are not understood, there at least may be delay in making a turn or, in the worst case, an accident could result if a protected operation is assumed where it does not exist.

Since older drivers have demonstrated a better understanding of the protected-only signal than of the permitted signal, its use is recommended, whenever reasonable, at high-volume intersections. Various studies have proven that installing protected left-turn phases improves left-turn safety because of the decrease in potential conflicts between left-turning and opposing through vehicles. The isolation of left-turning traffic usually reduces rear-end, angle, and sideswipe crashes, as well as improves the flow of through traffic. A protected/ permitted left-turn phase is not expected to provide the higher degree of safety of a protected-only phase, but it is likely to be safer than a permitted-only phase.

California reported a 35-percent average reduction in total crashes when left-turn lanes were constructed and left-turn phases were implemented, as opposed to a 15-percent reduction when left-turn lanes were installed without a separate left-turn phase (Neuman, 1985). Given the wide range of conditions, a consensus on the extent of this effectiveness has not been reached.

Signal-timing changes might affect the operational aspects of signalized intersections. Providing a protected left-turn phase might reduce an individual or coordinated system’s level of service. Agencies will have to consider the potential tradeoffs before making a final decision. The HCM (http://www.a3a10.gati.org/) can be used to determine the effect on delay and level of service.

For more information on providing more protected left-turn signal phases at high-volume intersections, see Strategy 17.2 A1 in the companion guide on crashes at signalized intersections.

Strategy 3.1 B6: Provide Offset Left-Turn Lanes at Intersections (T)

General Description

Studies examining older driver crashes and the types of maneuvers being performed just prior to the collision have consistently found that older drivers have more left-turn accidents at signalized intersections than younger drivers do. Common older driver errors include misjudging the oncoming vehicle speed, misjudging the available gap, assuming that the oncoming vehicle was going to stop or turn, and simply not seeing the other vehicle. Further, older drivers may experience greater difficulties at intersections as a result of diminished visual capabilities, such as depth and motion perception. These traits associated with older drivers can lead to collisions between vehicles turning left from the major road and through vehicles on the opposing major-road approach. To reduce the potential for crashes of this type, the left-turn lanes can be offset by moving them laterally, so that vehicles in opposing lanes no longer obstruct the opposing driver. Two treatments for offsetting turn lanes are parallel and tapered offset left-turn lanes (see Exhibit V-12).

Staplin et al. (1997) performed a laboratory study, field study, and sight distance analysis to measure driver age differences in performance under varying traffic and operating conditions as a function of varying degrees of offset or opposing left-turn lanes at suburban arterial intersections. Research findings indicated that an increase in sight distance through positively offsetting left-turn lanes can be beneficial to left-turning drivers, particularly older left-turning drivers.

While offset left-turn lanes have been used most extensively at signalized intersections, they are suitable for use at unsignalized intersections as well. Further discussion of offsets may be found in Appendix 7 and Strategy 17.1 B3 in the guide for addressing unsignalized intersection collisions.

Information on Agencies or Organizations Currently Implementing the Strategy

Exhibits V-13 and V-14 illustrate an offset left-turn lane at a signalized intersection in Wisconsin.

EXHIBIT V-12
Parallel and Offset Left-Turn Lanes (AASHTO, 2001)

EXHIBIT V-13
Offset Left-Turn Lane (Wisconsin DOT)

EXHIBIT V-14
Improved Sight Distance Due to Offset Left-Turn Lane (Wisconsin DOT)

Strategy 3.1 B7: Improve Lighting at Intersections, Horizontal Curves, and Railroad Grade Crossings (T)

General Description

Roadway accidents at night are disproportionately higher in number and severity than during the day. However, older drivers are involved in fewer nighttime accidents than in daytime accidents. This fact may be due to a number of factors, including reduced exposure—older drivers as a group drive less at night—and a self-regulation process whereby those who drive at night are the most fit and capable to perform all functional requirements of the driving task. Although older drivers drive less at night, lighting provides a particular benefit to older drivers because visual acuity deteriorates with age. Visual acuity may, in fact, be one of the key differences between older and younger drivers. The Older Driver Handbook (Staplin et al., 1998) has extensively documented that an older driver’s ability to safely execute a planned action is not significantly worse than that of a younger driver.

A “planned action,” however, requires that a driver have sufficient preview distance such that he can anticipate necessary vehicle maneuvers. The importance of fixed lighting for older drivers can, therefore, be understood in terms of both the reduced visual acuity and the need to prepare farther in advance for unusual or unexpected roadway elements, such as intersections, horizontal curves, and railroad grade crossings. Thus, improved lighting at these roadway elements will provide older drivers with additional preview distance and more time to prepare a planned action.

For more information on improving lighting at intersections and horizontal curves, see Strategies 17.1 E2, 17.2 D1 and 15.2 A9 in the companion guides for addressing unsignalized intersection collisions, signalized intersection collisions, and horizontal curve collisions, respectively.

Strategy 3.1 B8: Improve Roadway Delineation (T)

General Description

This strategy focuses on providing older drivers with better visual cues (e.g., pavement markings along the roadway, raised channelization at intersections, and delineators at horizontal curves) to recognize roadway elements. Recognizing roadway elements is important in order for older drivers to maintain their lane and to safely negotiate through an intersection or a horizontal curve. Older drivers tend to have reduced visual acuity, reduced field of view, increased decision time, and slower response time. These factors combine to put older drivers at greater accident risk when approaching and negotiating an intersection or a horizontal curve. Furthermore, research findings describing driver performance differences related to pavement markings and delineation focus upon age-related deficits in spatial vision.

A variety of conspicuity-enhancing treatments are mandated in current practice. The Manual on Uniform Traffic Control (MUTCD), for example, provides guidelines on pavement markings and delineation contrast. However, taking the MUTCD guidelines a step further by providing wider lane lines or edgelines with raised pavement markers would better accommodate older drivers’ reduced visual acuity.

Making older drivers more aware of roadway elements (e.g., pavement edges, intersections, and horizontal curves) through the use of enhanced pavement markings and delineation should improve overall safety. This heightened awareness will quicken older drivers’ reaction times when conflicts occur. However, this strategy’s effectiveness has not been quantified.

Pavement marking and other delineation devices can wear quickly and lose their retroreflectivity with time. Keeping such delineation properly maintained or improving its durability will also accommodate older drivers’ reduced visual acuity.

For more information on improving roadway visibility, see Strategies 17.1 E1 and 15.2 A2 in the companion guides for addressing unsignalized intersection collisions and horizontal curve collisions, respectively.

Information on Agencies or Organizations Currently Implementing the Strategy

The Iowa DOT conducted a focus group of older drivers and found that their most requested improvement is better pavement markings. So, improving roadway delineation is a priority of the Iowa DOT.

The Wisconsin DOT provides black contrast tape with yellow and white delineation, which has been found to be an effective tool, eliciting favorable public opinion.

The Atlanta District of TxDOT provides thermoplastic white on black striping for lane lines and edgelines (see Exhibit V-15).

EXHIBIT V-15
Thermoplastic White on Black Striping (Atlanta District, TxDOT)

Strategy 3.1 B9: Replace Painted Channelization with Raised Channelization (P)

General Description

One advantage of using raised channelization is that it gives a better indication to older drivers of the proper use of travel lanes at intersections than painted channelization gives. Raised channelization provides greater contrast and helps older drivers detect downstream geometric features, such as pavement width transitions, channelized turning lanes, and island and median features at an intersection. Older drivers’ poor contrast sensitivity has been shown to relate to increased crash involvement, when incorporated into a series of vision tests that include visual acuity and horizontal visual field size.

However, older drivers may be negatively affected by a raised median if it is inadequately reflectorized. Raised channelization represents a fixed object—when struck, it poses a serious threat of loss of control, especially for aging drivers. Therefore, it is particularly important to ensure the visibility of raised surfaces for older drivers so that older drivers can detect the channelizing devices and select the paths accordingly.

A forthcoming change in accessibility policy concerning pedestrian street crossings at channelized intersections may have substantial implications for future intersectionchannelization design policy.

EXHIBIT V-16
Strategy Attributes for Replacing Painted Channelization with Raised Channelization (P)

Attribute Description
Technical Attributes
Target The target for this strategy should be any intersection with painted channelization where older drivers find it difficult to see the painted channelization. The strategy is particularly appropriate for intersections with patterns of crashes related to improper lane use.
Expected Effectiveness The California Department of Public Works conducted a series of studies to investigate the difference in accident experience with raised versus painted channelization. The department found that raised traffic islands are more effective than painted islands are in reducing frequencies of night accidents, particularly in urban areas; little difference was found between raised versus painted channelizing islands at rural intersections (Neuman, 1985).

Another study (McFarland et al., 1979) not only documents the safety benefit of left-turn channelization but also demonstrates the additional benefits of raised channelization. At unsignalized intersections with painted channelization separating the left-turn lane from the through lane, McFarland et al. found that total accident frequency was reduced for rural, suburban, and urban areas by 50, 30, and 15 percent, respectively. When raised channelization was used, the accident reductions were 60, 65, and 70 percent in rural, suburban, and urban areas, respectively.
Keys to Success The key to success for this strategy is to ensure the visibility of raised surfaces for older drivers so that older drivers can detect the channelizing devices and select the paths accordingly.

If the raised channelization is reflectorized, another key to success is the ability and commitment of the highway agency to adequately maintain the reflectorization.
Potential Difficulties Older drivers—having poorer vision, slower physical reaction time, less awareness, and less ability to maneuver the vehicle—may be negatively affected by a raised median (Transportation Research Board, 1991). Also, because raised medians are fixed objects, they pose serious threat of loss of control when struck, especially for older drivers.
Appropriate Measures and Data Key process measures are the number of intersection approaches where painted channelization was replaced with raised channelization and the number of potential conflicts eliminated by the improvements.

Crash frequency and severity, by type (by age group), are key safety effectiveness measures. If feasible, both total crashes and crashes related to channelization should be analyzed separately. Driver behavior (e.g., vehicle paths, erratic maneuvers, and conflicts) may be used as surrogate safety measures. Traffic volume data are needed to represent exposure.
Associated Needs None identified.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Nearly any highway agency can implement this strategy.
Issues Affecting Implementation Time This strategy does not require a long development process. Raised channelization may take from 3 months to 1 year to implement.
Costs Involved Costs to install raised channelization may vary, but will likely be in the middle range of intersection improvements.
Training and Other Personnel Needs Training regarding use of this strategy should be provided in highway agency courses covering the use of traffic control devices, with special emphasis on older drivers’ needs.
Legislative Needs None identified.
Compatibility of Different Strategies This strategy can be used in conjunction with most other strategies for improving the roadway and driving environment to better accommodate older drivers’ special needs.
Other Key Attributes
None identified.

Strategy 3.1 B10: Reduce Intersection Skew Angle (T)

General Description Intersections where two roadways intersect at an angle of less than 60 degrees are considered skewed intersections (see Exhibit V-17).

An intersection whose skew angle is between 60 and 75 degrees is also considered undesirable. Skewed intersections pose particular problems for older drivers. Many older drivers experience a decline in head and neck mobility. A restricted range of motion reduces an older driver’s ability to effectively scan to the rear and sides of his or her vehicle to observe blind spots. Therefore, older drivers’ diminished physical capabilities may affect the performance at skewed intersections, where drivers must turn their heads farther than at a right-angle intersection. This obviously creates more of a problem in determining appropriate gaps.

Reducing intersection skew angle lessens the amount of head and neck rotation required of older drivers and provides a wider field of view for the driver to recognize conflicts and select appropriate gaps. Therefore, it is recommended that in the design of new facilities or redesign of existing facilities, intersecting roadways meet at a 90-degree angle or be skewed as little as possible.

For more information on reducing intersection skew angle, see Strategy 17.1 B16 in the guide for addressing unsignalized intersection collisions.

EXHIBIT V-17
Skewed Intersection

Strategy 3.1 B11: Improve Traffic Control at Work Zones (T)

General Description

Work zones often violate driver expectancy. Coupled with the functional deficits associated with normal aging, older drivers are at greater risk when negotiating work zones. Therefore, work zones deserve special consideration with respect to older drivers. To improve driver expectancy through a work zone, traffic control devices must provide adequate notice to drivers describing the condition ahead, the location, and the required response. Once a driver reaches the work zone, all signing, channelization, and delineation must be conspicuous and unambiguous in providing guidance through the work area.

To enhance the performance of older drivers through work zones, the Older Driver Handbook (http://ntl.bts.gov/DOCS/older/intro/index.html) provides recommendations for improved traffic control at work zones that relate specifically to the following areas:

  1. Advance signing for lane closures,
  2. Variable message sign practices,
  3. Channelization practices,
  4. Delineation of crossovers or alternative travel paths, and
  5. Temporary pavement markings.

Information on Agencies or Organizations Currently Implementing the Strategy

In advance of work zones, Arizona DOT provides large signs that indicate that fines will be doubled for speeding within work zones. The DOT has found this approach to be very effective in reducing speeds.

To improve the visibility of signing at work zone locations, Iowa DOT provides highly reflective orange signing with lime green contrast trim.

EXHIBIT V-18
Strategy Attributes for Improving Traffic Control at Work Zones (T)

Attribute Description
Technical Attributes
Target This strategy targets work zones that violate older drivers’ expectancy, given reduced or impaired visual, cognitive, and/or psychomotor abilities.
Expected Effectiveness It is difficult to quantify the effectiveness of this strategy. However, studies have shown that more accidents occur on highway segments containing work zones than on the same segments before the work zones were installed (Staplin et al., 1998). Improving the traffic control through work zones is expected to better meet driver expectancy for older drivers and for others, which can reduce accidents.
Keys to Success There are several keys to this strategy’s success. First, highway agencies must review their policies on work zone traffic control to identify ways to improve the policies. As indicated in the general description, the Older Driver Highway Design Handbook (Staplin et al., 1998, http://ntl.bts.gov/DOCS/older/rs/) provides recommendations for improving traffic control in five specific areas. Second, implementation of the improvements must be done in a consistent manner throughout all work zones in the region. Finally, maintenance of the traffic control at work zones (e.g., construction barrels and temporary striping) is key to the success of this strategy. Barrels often get moved—sometimes into the direct path of vehicles—and reflectivity of signing, striping, and other delineation treatments is not always maintained.
Potential Difficulties Agencies must routinely check all traffic control devices to verify that they are conspicuous, that they are properly placed, and that they convey the intended message according to the work zone traffic control plan. With all the dust and dirt in work zones, traffic control devices can become displaced or dirty and/or lose their conspicuity, thus becoming difficult for drivers to see and interpret properly. In other cases traffic control devices may be hit by construction equipment or passing traffic and may no longer work. If a device is missing, broken, obscured, etc., the agency must act quickly to remedy the situation.
Appropriate Measures and Data A key process measure is the number of work zones where improvements to the traffic control plan were identified and implemented.

Crash frequency and severity, by type (by age group), are key safety effectiveness measures. Traffic volume data are needed to represent exposure.
Associated Needs Agencies may wish to conduct a public information campaign to educate drivers on new work zone traffic control policies.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Agencies are encouraged to conduct a thorough review of their work zone traffic control policies. A cooperative regional effort is desired to attain consistency.
Issues Affecting Implementation Time Because a review of the agency’s work zone traffic control policy may be required, this strategy may require several months.
Costs Involved Costs to implement this strategy are expected to be minimal.
Training and Other Personnel Needs Training regarding this strategy should be provided in highway agency training courses that cover the use of traffic control devices at work zones.
Legislative Needs None identified.
Compatibility of Different Strategies This strategy can be used in conjunction with most other strategies for improving safety.
Other Key Attributes
None identified.

Objective 3.1 C—Identify Older Drivers at Increased Risk of Crashing and Intervene

Strategy 3.1 C1: Strengthen the Role of Medical Advisory Boards (T)

General Description

According to a recent National Highway Traffic Safety Administration (NHTSA) study, 35 states and the District of Columbia have medical advisory boards (MABs), although many of the MABs are relatively inactive (Lococo, 2003). Most operate under the auspices of state transportation, public safety, or motor vehicle departments. Board members are typically nominated or appointed by the state medical association, motor vehicle administrator, or governor’s office and are practicing physicians or health professionals from a variety of fields, including ophthalmology, neurology, internal medicine, cardiology, orthopedics, optometry, and psychiatry. Although MAB members are sometimes involved in the review of individual cases, they generally serve in a policy setting and/or advisory capacity.

With the growth in the older driver population, MABs in a few states have been rejuvenated to deal with the increased number and complexity of cases involving older adults with chronic medical conditions (e.g., dementia and arthritis) and general declines in functional capabilities. However, information is just now being gathered on how these boards function and how important a role they play in ensuring the competency of older drivers. In Maryland, the MAB has played a very active role in evaluating individual cases of suspected medical impairment and has helped to bring together a broad coalition of medical and nonmedical professionals to assist older adults in making appropriate driving decisions. In contrast, the California MAB, consisting of specialty panels of physicians, other health professionals, and representatives of various state agencies, is only convened when needed to make formal policy recommendations with regard to medically and functionally impaired drivers. Specially trained department of motor vehicles staff members make individual driving assessments and decisions (Raleigh and Janke, 2001; Lococo, 2003).

To better understand the role and functioning of MABs, NHTSA collaborated with the American Association of Motor Vehicle Administrators (AAMVA) to conduct a 2003 survey of all state MABs (see Lococo, 2003, available on AAMVA’s Web site at http://www.aamva.org/Documents/drvSummaryofMedicalAdvisoryBoardPractices.pdf). The next step of the project is to identify best practices in this area. State MABs are again being surveyed to help identify the most important aspects of a medical review program. The results of this effort should provide valuable feedback to the states as well as ideas for modifying and strengthening MABs to better address older adults’ safety and mobility needs.

In the meantime, states can conduct their own systematic review to determine whether their MAB can play a broader role in ensuring the safety of licensed drivers of any age with medical conditions or functional impairments that can compromise the ability to safely operate a motor vehicle. Where possible, information about the MAB could be posted on motor vehicle department and state medical association Web sites so that the general public, as well as the medical profession, can become better informed about the MAB’s existence and role. Also, states should ensure that gerontologists and/or geriatricians are represented on the MABs.

EXHIBIT V-19
Strategy Attributes for Strengthening the Role of Medical Advisory Boards (T)

Attribute Description
Technical Attributes
Target The target audiences for this strategy are state departments of motor vehicles, MABs, and medical associations. The actual target of the activities is drivers of any age who experience significant declines in driving capability due to medical impairments.
Expected Effectiveness There have been no studies evaluating the effectiveness of state MABs, per se. However, a NHTSA-funded study currently underway has documented state practices with regard to MABs and is developing a report on best practices (see Lococo [2003] for the completed review of current practices). Studies have also been conducted of the effectiveness of various programs that might involve an MAB, such as required reporting of drivers with medical conditions that may adversely affect their driving or the evaluation of a program for identifying and assessing impaired older drivers. A 1986 evaluation of Pennsylvania’s “Older Driver Reexamination Program” demonstrated clear safety benefits for drivers age 60 and older (Freedman et al., 1986). Under the program, a sample of drivers, age 45 and older, were selected for retesting prior to renewing their license. For drivers age 60 and older, the program was shown to be effective in discovering medical and visual conditions requiring licensing restrictions, revocation, or remediation. In the Canadian province of Saskatchewan, drivers with identified medical conditions who participated in the Medical Review Program over 10 years (1980–1989) were found to have fewer at-fault crashes than a matched sample of nonparticipating drivers (Medgyesi and Koch, 1994).

The MAB in Maryland, under the leadership of Dr. Robert Raleigh, has played a particularly active role in establishing and evaluating a Model Driver License Improvement Program. Information on this program is available from Staplin and Lococo (2003).
Keys to Success Anticipated keys to success include a commitment by the department of motor vehicles and the state medical association to create and support a strong and active MAB. The appointment of gerontologists, ophthalmologists, optometrists, and others who specialize in treating older adults can also help ensure that the needs of this population are addressed.
Potential Difficulties Creating a strong and active MAB where one does not already exist is no simple task. However, the vast majority of states already have at least the basic structure in place. In these states, the greatest barrier to strengthening the program may be a lack of commitment by the motor vehicle department and state medical association. In addition, some states may lack clear guidelines for assisting MAB members in performing their function. States that rely entirely on volunteer service may experience greater difficulty in filling available positions on the MAB. Finally, the greatest difficulty may simply lie in changing the status quo, especially in states that have had relatively inactive MABs in the past.
Appropriate Measures and Data Process measures include whether an MAB is in place, the composition of the MAB, and the existence of guidelines covering its activities.

Institutional impact measures include data on the MAB’s activities, including cases reviewed, the disposition of these cases, and assistance provided to the department of motor vehicles with regard to medical issues and driving.

Effectiveness is to be ultimately measured by comparing the crash experience of groups affected by the programs, either with control populations or those not affected.
Associated Needs Associated needs primarily pertain to support from the department of motor vehicles and the state medical association, as well as individual physicians and other medical professionals willing to serve on the board. It may require special effort to inform department of motor vehicles personnel of the potential benefit of this strategy. Also, board members may require special training in order to carry out their new or expanded responsibilities, and these training materials will need to be developed (see training and other personnel needs below).
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Legislation and/or policy changes may be necessary to expand or change the MAB’s role or to create an MAB where none currently exists.
Issues Affecting Implementation Time The primary issues affecting implementation time is whether resources (both financial and personnel) can be made available to the effort of evaluating and expanding/ strengthening the role of the MAB and the current level of functioning of the state’s MAB.
Costs Involved Costs will vary depending on the MAB’s current status and level of expertise, but should be fairly minimal.
Training and Other Personnel Needs Physicians, ophthalmologists, and other health care professionals who are asked to serve on the state’s MAB may or may not be knowledgeable of the medical aspects of driving, the impact of various medical conditions and functional impairments on driving ability, how age affects abilities related to driving, and the significance of mobility to the elderly. Education and training in all of these areas may be necessary. While the state medical association might provide some of this training, licensing personnel and members of the highway safety community could also be called upon to participate in seminars and other training opportunities. In all such training, it must be emphasized that neither age nor the diagnosis of a medical condition is sufficient for determining fitness to drive; rather, driving decisions should be based on an individual’s demonstrated functional abilities related to driving (see Strategy 3.1 B2).
Legislative Needs As noted above, in some states legislation may be needed to create an MAB where none exists or to expand the composition and/or responsibilities of an existing MAB.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

According to the most recent available data, 35 states and the District of Columbia currently have MABs; however, they appear to vary significantly in terms of composition, activity level, primary responsibilities, and modes of operation. As noted above, a NHTSA study currently underway will greatly expand knowledge of current practices and offer guidance to states on increasing the effectiveness of MABs.

Strategy 3.1 C2: Update Procedures for Assessing Medical Fitness to Drive (P)

States vary considerably with respect to how they identify and evaluate medically at-risk drivers, and they decide motorists’ fitness to drive. While most states have procedures or guidelines in place for licensing persons with identified medical conditions and/or functional impairments, many of these guidelines are outdated, incomprehensive, and based on disease diagnosis rather than level of functional impairment. NHTSA has issued a report on older driver issues, including an Annotated Research Compendium of Driver Assessment Techniques for Age-Related Functional Impairments (see http://www.nhtsa.dot.gov/people/injury/olddrive/safe/safe-toc.htm)

The Association for the Advancement of Automotive Medicine (AAAM), working with NHTSA, recently completed a detailed literature review summarizing knowledge about various categories of medical conditions (cerebral vascular, nervous system, musculoskeletal, etc.), their prevalence, and potential impact on driving ability (Dobbs, 2002). The American Medical Association (AMA) used this report in developing a physician’s guide for assessing patients’ medical fitness to drive (AMA, 2003). In addition to recommendations for licensing drivers with specific medical conditions, the guide includes information on driver assessment strategies, rehabilitation options, counseling practices, and additional resources for both physician and patient.

The AMA guide is being marketed to physicians and other health professionals nationwide. Drawing from both the AMA guide and the AAAM review, it is recommended that state motor vehicle departments review and update their own guidelines for licensing persons with medical conditions and/or functional impairments. The guidelines should encompass all medical conditions known to affect driving ability and be based upon level of functional impairment rather than disease diagnosis per se. For example, rather than recommend revoking the licenses of persons diagnosed with Alzheimer’s Disease (AD), the guideline might recommend that healthcare professionals periodically reevaluate AD and relate licensing decisions to patients’ cognitive performance level.

As an alternative to developing their own guidelines, states might support the AAMVA in developing an updated set of national recommended guidelines for assessing medical fitness to drive and then adopt these national guidelines as their own. The benefit would be greater consistency across states, as well as economy of effort (i.e., each state does not need to “reinvent the wheel”).

The resulting guidelines should be incorporated as appropriate into training materials for driver license examiners and other field representatives. State motor vehicle departments should also work with their MAB and/or state medical association to educate physicians about the guidelines and to encourage them to incorporate the AMA materials into their practices.

In addition, states that require driver’s licenses to be renewed in person have further opportunities for identifying drivers of any age with medical conditions or functional impairments that could adversely affect their driving. In a survey of license examiners in all 50 states and the District of Columbia, how a person looks when they come through the door at the department of motor vehicles was the single most important criterion for identifying an impaired driver (Cobb and Coughlin, 1997). Earlier, Petrucelli and Malinowski (1992) had concluded that “the examiner’s personal contact with the applicant is the only routine opportunity to detect potential problems of the functionally impaired driver. This opportunity should not be lost because of inadequate training.” The recently updated Model Driver Screening and Evaluation Program: Guidelines for Motor Vehicle Administrators (Staplin and Lococo, 2003) strongly recommends in-person license renewals with a requirement that department of motor vehicles line personnel complete a very brief checklist of structured observations. Guidelines from Wisconsin are offered as an example (see Appendix 8). These guidelines, based on visual inspection, were not judged to be discriminatory under current ADA regulations. The program also recommends that training be provided to department of motor vehicles line personnel to assist them in carrying out this responsibility.

If mail-in renewal practices are permitted, the program recommends a policy requiring third-party screening for gross impairments in relevant visual, mental, and physical abilities, along with clear guidelines for conducting, documenting, and reporting the results of these procedures to the department of motor vehicles prior to granting license renewal. The program also recommends that both in-person and mail-in renewals incorporate forms for renewal applicants to self-report medical conditions or symptoms on the license renewal application. A form used by the Utah Driver License Division is offered as an example (see Appendix 9).

EXHIBIT V-20
Strategy Attributes for Updating Procedures for Assessing Medical Fitness to Drive (P)

Attribute Description
Technical Attributes
Target The target audience for this strategy is state motor vehicle departments along with state MABs and/or state medical associations.
Expected Effectiveness There have been a number of evaluations of the impact of state programs for licensing persons with medical impairments. One of the most recent is a study carried out in the state of Utah (Diller et al., 1999). Drivers in Utah are required to identify any medical problems when renewing their license and, depending upon their assigned functional ability level, may be given either an unrestricted license or a license with restrictions or be denied a license. For the recent study, rates of adverse driving events (crashes, at-fault crashes, and citations) experienced by drivers who had self-reported medical conditions and who had either restricted or unrestricted driver’s licenses were compared with a sample of age- and sex-matched controls. Drivers in the medical review program were found to have only modestly elevated rates of adverse driving events compared with the matched controls, suggesting that the program was having the intended effect of lowering crash rates. In an unpublished evaluation carried out in Saskatchewan, drivers with medical conditions who were identified and placed into a medical review program were found to have lower at-fault crash rates than a control group with similar medical impairments who were not identified to licensing authorities (Medgyesi and Koch, 1994).

Other evaluations include evaluations of medically impaired drivers in California (Waller, 1965; Janke, 1994), an evaluation of medically restricted drivers in Oklahoma (Davis et al., 1973), and an evaluation of restricted drivers in North Carolina (Popkin and Stewart, 1992). In general, these studies have shown that while identifying and placing driving restrictions on the licenses of persons with medical impairments can lower their crash risk, it still remains elevated compared with unrestricted drivers.

In a recent California study, department of motor vehicles staff’s use of structured observation methods was found to significantly increase the number of drivers identified with medical or functional impairments (Janke and Hersch, 1997).
Keys to Success Involvement of the state medical association and/or state MAB is advisable in developing appropriate guidelines. It is critical that the guidelines be objective and based upon an individual’s level of physical, mental, and /or sensory function, as opposed to disease diagnosis. Licensing personnel must also be trained in proper use of the guidelines. Provision should be made for temporary license reinstatement where appropriate to allow those affected to seek further evaluation and/or training.
Potential Difficulties The primary difficulty is in making appropriate recommendations for licensing in the absence of firm data on the impact of certain medical conditions and related functional impairments on driving safety. Also, there may be public opposition to increased screening and/or reporting. If additional screening and/or assessment procedures are incorporated into the license renewal process, it should be recognized that these procedures may result in increased time and costs for licensing agencies.
Appropriate Measures and Data Process measures include whether a procedure is in place for reviewing and updating existing state procedures or guidelines and whether appropriate parties are involved in the process. Other process measures include whether licensing guidelines are updated to reflect current knowledge and practice and the number of licensing personnel trained in their use.

Effectiveness can be measured in terms of the degree to which the procedures or programs in place are successful in identifying at-risk drivers, the disposition status of the identified drivers, and ultimately their involvement in crashes compared with either a control group or those not involved in the program.
Associated Needs Input and support from the medical and public health communities are needed.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues To be effective, this strategy requires that state motor vehicle departments work cooperatively with the medical community, including the state medical association and MABs. Legislative or policy changes may be needed to allow departments of motor vehicles to require in-person license renewals or to require self-reporting of potential medical impairments.
Issues Affecting Implementation Time States that already have medical guidelines and working relationships with state MABs and/or state medical associations should be able to carry out this strategy within a shorter timeframe than states lacking these resources. In addition, adequate time will be needed to train driver license examiners in implementing any new guidelines or procedures.
Costs Involved Costs associated with updating medical guidelines primarily involve dedication of staff time to assemble the necessary participants in the review process and to develop the revised guidelines. Larger costs will likely be associated with training of licensing personnel in implementing any new guidelines or procedures and establishing a system for following up with the identified cases (for example, if a medical report or an on-road drive test is required).
Training and Other Personnel Needs Medical personnel may need to be involved in the initial training efforts, and some “train the trainer” programs may be needed. However, adequate guidelines should be in place so that identification of impaired drivers is incorporated into ongoing training of licensing personnel. As noted above, additional staffing may be needed to accommodate any increase in caseload as a result of implementing the new procedures for identifying at-risk drivers.
Legislative Needs None identified.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

Most states already have guidelines in place for the licensing of medically impaired drivers. Examples of recent state guidelines include the following:

  1. State of Utah Functional Ability in Driving: Guidelines and Standards for Health Care Professionals. Utah State Driver License Medical Advisory Board. 1992. (See Appendix 9; also included as an appendix in the report by Diller et al., 1999)
  2. The North Carolina Physician’s Guide to Driver Medical Evaluation. Injury Control Section, Division of Epidemiology, North Carolina Department of Environment, Health, and Natural Resources. 1995.

In addition, both Wisconsin and Florida have guidelines for license examiners to follow in identifying potentially impaired drivers:

  1. Wisconsin Driver Licensing Manual, State of Wisconsin. Section 235 “Evaluating Medical Conditions of Disabilities.”
  2. Florida Examiner’s Manual. Chapter 9 “Medicals & Department Re-Examinations” and Chapter 11 “Restrictions/Adaptive Equipment.”
  3. Staplin, L., and K. H. Lococo. Model Driver Screening and Evaluation Program. Volume III: Guidelines for Motor Vehicle Administrators. Final Report for NHTSA Project Number DTNH22-96-C-05140, May 2003. [Available online at http://www.nhtsa.dot.gov/people/injury/olddrive/modeldriver/]

Strategy 3.1 C3: Encourage External Reporting of Impaired Drivers to Licensing Authorities (T)

General Description

In addition to identifying at-risk drivers internally, through the license renewal process, at-risk drivers can also be identified externally through reporting by physicians, law enforcement officers, and private citizens (usually either family members or friends of an older adult). Each of these avenues for identifying high-risk drivers is briefly addressed below, as are suggestions for involvement by state motor vehicle departments.

Reporting by physicians and other medical professionals. Currently, only six states (California, Delaware, Nevada, New Jersey, Oregon, and Pennsylvania) require physicians to report patients with potential driving impairments (most often recurrent loss of consciousness) to licensing authorities; however, 31 states provide immunity from legal action to physicians who do report patients (Lococo, 2003). A recent report by the AMA Council on Ethical and Judicial Affairs clarifies the physician’s role in reporting patients with physical or mental impairments that may adversely affect driving abilities (AMA, 1999; see Appendix 10). The report outlines the following conditions for reporting: (1) the patient has identified and documented impairments clearly related to the ability to drive; (2) the patient poses a clear risk to public safety; (3) alternatives to reporting, including remediation and training, driving restrictions, and patient and family counseling, are insufficient; and (4) the patient does not voluntarily comply with the physician’s recommendation to discontinue driving. In these limited cases, the AMA guidelines state that “it is desirable and ethical for physicians to notify the Department of Motor Vehicles about the medical conditions that may impair safe driving to enable the Department of Motor Vehicles to determine whether or not the patient can continue to drive.”

There are significant impediments to full compliance with the AMA recommendations (Staplin et al., 2003). These include the requirement that physicians be able to identify and document the physical or mental impairments clearly related to the ability to drive and the requirement that the driver must pose a clear risk to public safety. Standardized assessment tools and better guidelines are needed. The recently completed NHTSA/AAAM guidelines (Dobbs, 2002) and NHTSA’s ongoing activity with the AMA (see Strategy 3.1 B2 above) should provide a stronger basis for more consistent programs across states, as well as more consistent compliance within states that have reporting laws in place. State motor vehicle departments should work with their state medical associations and MABs to educate physicians about the importance of discussing driving with their patients and advising them to self-report if the physicians feel that the patient’s driving ability may be compromised. By doing this, physicians will lessen the need to report impaired drivers to state licensing authorities.

Reporting by law enforcement. With regard to reporting by law enforcement personnel, a survey of driver licensing agencies in seven states (California, Connecticut, Florida, Michigan, Oregon, Texas, and Wisconsin) indicated that 24 percent of all referrals submitted come from law enforcement officers (Sterns et al., 2001). While officers are generally not qualified to make medical judgments about an individual’s ability to drive, they can be trained to recognize behavioral indicators of age-related impairments and to make appropriate referrals. NHTSA recognizes the important role that law enforcement can play in identifying high-risk older drivers and has prepared an informational pamphlet outlining various “cues” an officer should pay attention to when encountering a potentially impaired older driver (NHTSA, 1998; see Appendix 14). The cues are all performance based rather than age based. They include a lack of awareness of the current date and time, inability to communicate, stumbling over words, difficulty finding and removing one’s driver license, and difficulty walking short distances. The identified cues were field tested by Florida State Troopers in Pinellas County during routine crash investigations and traffic stops. The pamphlet also offers suggestions for ways law enforcement officers can intervene to assist the impaired older driver. Since this time, a training video has been developed for law enforcement officers and distributed to highway patrol offices nationwide (Hunt, 2000), and work is underway to develop a training course specifically to address aging driver issues.

Reporting by family and friends. Finally, many states have specific systems in place for family members and friends to report potentially impaired drivers. In a survey of driver license administrators, almost all respondents indicated that it would be feasible to have a family member or friend refer a driver they felt might be impaired to the department of motor vehicles (Staplin at al., 2003). Family and friends were found to account for about 10 percent of referrals to the seven state departments of motor vehicles surveyed by Sterns et al. (2001), with family members accounting for the largest share. While reports typically cannot be made anonymously, in most situations the referral source is kept confidential. A popular view of an approach to this strategy can be found at http://www.ec-online.net/Knowledge/Articles/safedriving.html.

EXHIBIT V-21
Strategy Attributes for External Reporting of Drivers with Functional Impairments (T)

Attribute Description
Technical Attributes
Target The target of this strategy is impaired or at-risk older drivers in the general driving population, along with the physicians and other health professionals, law enforcement officials, and/or family members who can help to identify these at-risk older drivers to licensing authorities.
Expected Effectiveness State systems to encourage reporting of impaired older drivers by physicians or other health professionals, law enforcement personnel, and private citizens have been shown to increase the number of cases reported. In Pennsylvania, reporting by physicians increased substantially in 1994 following an information campaign in which letters were sent to 46,000 physicians in the state informing them of potential legal consequences of not reporting. Currently the state processes approximately 16,000 medical referrals per year, with 49 percent of these for drivers age 45 and older. In addition, it receives approximately 2,000 reports from law enforcement personnel and 500 referrals from family members for drivers of all ages (Lococo, 2003). Oregon has also increased its number of cases reported each year to more than 5,000, with about 55 percent of these drivers age 55 and above. The Oregon referrals result from a combination of health provider, law enforcement, department of motor vehicles staff, and private citizen reporting (Sterns et al., 2001). In Missouri, “Driver Condition Report” forms are being made available at licensing offices through the state, and the form can also be downloaded from the Driver License Bureau website (http://www.dor.state.mo.us/mvdl/drivers/unsafe.htm). The Wisconsin Department of Motor Vehicles is evaluating the effectiveness of its Driver Condition/Behavior Report system for identifying high-risk drivers and improving their safety. Preliminary results of the evaluation indicate that, while the number of crashes and citations for drivers with behavior reports are still higher than those of the overall population, there is a significant reduction in incidents following submission of the reports (McCullough et al., 2001).

Research has shown that traffic crashes and stops for traffic violations are the primary opportunities law enforcement officers have for making referrals (McKnight and Urquijo, 1993).

The NHTSA “Cues for Law Enforcement” was field evaluated by Florida State Troopers in Pinellas County during a 1-month period in 1998 and found to offer effective guidelines for identifying potentially impaired older drivers encountered in traffic crash investigations or traffic stops (NHTSA, 1998; see Appendix 14).

Further evaluations are needed to determine the ultimate effectiveness of the strategy in reducing older-driver crashes.
Keys to Success Keys to success include (1) having the necessary systems in place, including any needed reporting forms, (2) publicizing the systems (e.g., to physicians, at driver licensing offices, on department of motor vehicles Web sites), (3) making reports confidential (but not necessarily anonymous), (4) providing appropriate training and materials to law enforcement officers, (5) working with the MAB and state medical association to help educate physicians and other health professionals, and (6) having a system in place to follow up on the resulting referrals. Holding physicians harmless for reporting, but making them culpable for not reporting, can increase physician compliance with reporting laws.
Potential Difficulties Potential difficulties include the logistics of educating and training physicians and law enforcement personnel and possibly opposition by some groups to reporting by private citizens (especially nonfamily members). In addition, appropriate procedures and programs need to be in place to assist individuals whose driving privileges are restricted or revoked to help counter the negative effects (both psychological and practical) for the driver.
Appropriate Measures and Data The key process measure is the documentation of the completion of the six items listed above in “Keys to Success.”

Impact measures include the number of reported cases (along with information on the source and reason for reporting and the disposition of the reported cases) and the change in crash involvement of elderly drivers.
Associated Needs Cooperation and support of the medical community, including the state medical association, as well as the law enforcement community, are essential.

Extensive public information and education programs will be needed to gain public awareness and involvement.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues As noted above, this strategy requires collaboration with both the medical community and law enforcement agencies. Legislation may be needed to require physician reporting and/or to provide immunity from legal action by patients who are reported.
Issues Affecting Implementation Time The timeframe for this strategy will be affected by the extent that systems are already in place (e.g., required reporting by physicians and law enforcement reporting of impaired drivers).
Costs Involved Costs will vary depending upon which reporting systems are used. The greatest costs may lie in training law enforcement officers and conducting a public information and education campaign. Minimal costs would be associated with reporting systems for physicians and family/friends, other than the cost of following up on the referrals.
Training and Other Personnel Needs As noted above, both physicians and law enforcement officers will require education and training in procedures for identifying at-risk drivers.
Legislative Needs None identified.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

The Oregon Department of Motor Vehicles has taken a comprehensive approach to addressing the safety and mobility needs of its aging driving population through its At-Risk Driver Program (requiring physician and other health provider reporting of drivers with certain cognitive or functional impairments); Volunteer Medical Program (for reporting by law enforcement and family or friends); and public outreach campaign (with the theme, “Shifting Gears in Later Years”). More information on these programs is contained in Appendix 12 and on the following Web sites:

  1. http://www.odot.state.or.us/dmv/DriverLicensing/atriskquestions.htm
  2. http://www.oregonsafemobility.org

Other sample programs and activities include the following:

  1. Florida’s outreach program to encourage reporting of unsafe drivers (http://www.hsmv.state.fl.us/ddl/helpful.html)
  2. Missouri’s program for reporting unsafe drivers (http://www.dor.state.mo.us/mvdl/drivers/unsafe.htm)
  3. Minnesota’s outreach efforts to encourage voluntary reporting of at-risk drivers (http://www.dps.state.mn.us/dvs/AtRisk/AtRiskset.htm)
  4. The Ocean County, New Jersey, Safe Outreach for Seniors (SOS) program for law enforcement reporting to health professionals (Howell and Macaluso, 2001)
  5. The Pinellas County, Florida, project with NHTSA for law enforcement reporting

Strategy 3.1 C4: Provide Remedial Assistance to Help Functionally Impaired Older Drivers (T)

General Description

This strategy builds on previous strategies under this objective and is a key element in a comprehensive program to address older adults’ safety as well as mobility needs. Given the importance of driving to maintain independence and to preserve health and quality of life, if functional deficiencies that impair driving abilities are identified and remedial options exist, remedial assistance should be made available to the driver. Remedial programs provide ideal opportunities for the public and private sectors to work together toward a common goal and for departments of motor vehicles to join with other agencies and the medical and health communities to facilitate something that the agencies could not accomplish on their own.

Driver remediation can be carried out by the department of motor vehicles, which can impose nighttime driving restrictions on drivers whose vision does not meet required standards. The department of motor vehicles can also mandate that mirrors or other adaptive equipment be added to the driver’s vehicle. If the driver’s deficiencies are more complex and/or if medical conditions are involved, the department of motor vehicles can refer the case to the MAB for its assessment and recommendation.

Options also exist beyond the department of motor vehicles. In particular, a growing number of occupational therapists are trained to evaluate and provide remedial assistance to drivers with functional impairments. While not all functional losses can be successfully treated, occupational therapists are especially well qualified to assist some older adults who otherwise might be forced to stop driving. Another option is local driving schools. Not every driving school has staff qualified to evaluate and retrain the older driver, but those that do can provide a valuable service that can potentially benefit larger numbers of older drivers. The challenge with both these options comes in how the department of motor vehicles can work cooperatively with other agencies and with the health community to promote the use of these options.

The recently completed Model Driver Screening and Evaluation Program (Staplin and Lococo, 2003; http://www.nhtsa.dot.gov/people/injury/olddrive/modeldriver/) recommends that states have specific guidelines in place to impose appropriate restrictions on the licenses of impaired drivers. It also encourages departments of motor vehicles to provide drivers with information on remediation options outside the department of motor vehicles and how these options can be accessed. Table 5 in the report’s Guidelines for Motor Vehicle Administrators provides examples of licensing restrictions and adaptive equipment requirements that licensing officials can impose to help counteract physical impairments common to the elderly. Table 6 provides information on a broad range of additional remedial options to help impaired older adults drive safely longer.

The above NHTSA report also recognizes the important role that education and counseling activities can play in helping older adults to recognize potential impairments that could affect driving and to access available resources to help extend their safe driving years. Included in these activities are self-assessments guides, which also typically contain suggestions for addressing any identified deficiencies. Examples of such guides are included under Strategy 3.1 D2.

EXHIBIT V-22
Strategy Attributes for Remedying Older Driver Functional Impairments (T)

Attribute Description
Technical Attributes
Target The targets of this strategy are older adults with visual, cognitive, and/or psychomotor impairments that place the adults at increased risk of crashing.
Expected Effectiveness The effectiveness of this strategy varies, depending upon the specific type of action taken for the driver. Overall effectiveness of such a program has not been studied.

See Technical Attributes for Strategy 3.1 C2, Update Procedures for Assessing Medical Fitness to Drive, for information on the effectiveness of licensing restrictions on older driver crash rates.

Data with respect to the effectiveness of other remediation strategies are less clear, especially since these are not carried out in driver license settings. The Model Driver Screening and Evaluation Program (Staplin and Lococo, 2003), piloted in Maryland, included driver counseling and rehabilitation as components of the model program. However, further research is needed to determine the long-term crash-reduction and mobility-enhancement benefits of the program.

A study carried out in St. Louis, Missouri, found that driver remediation through adaptive equipment and training, under the direction of an occupational therapist specially trained in driver rehabilitation, helped a significant proportion of impaired drivers (many of whom were recuperating from stroke) resume driving. At the same time, however, the evaluation process identified other drivers who were found to be unsafe, but who had no prior knowledge of their inability to drive safely (Hunt, 2000).

Owsley (2001) reported that providing counseling and education to drivers with identified visual impairments increased driving safety by promoting greater selfregulation and by reducing driving exposure. In addition, Owsley’s research has shown that cataract surgery reduces the risk of crashes by one-half, compared with older drivers who elect not to have the surgery (Owsley et al., 2002).
Keys to Success Some keys to success include (1) having clear guidelines for license examiners to use in making decisions regarding the licensing of drivers with identified functional impairments (e.g., time-of-day restrictions on driving or vehicle equipment requirements), (2) having an MAB to assist in making decisions about the licensing status of drivers with more serious medical impairments, and (3) linking department of motor vehicles offices with private-sector facilities (e.g., driver rehabilitation centers, certified driving rehabilitation specialists, and local driving schools) to provide additional evaluation and remedial help when needed.
Potential Difficulties Researchers have identified a number of barriers to the implementation of remedial programs for impaired older drivers (Staplin, personal communication): (1) lack of information and education (neither the public nor the health community are well informed of the resources available for assessing, referring, and treating older adults); (2) inadequate infrastructure for comprehensive program offerings for older individuals (in particular, the absence of MABs or similar units to provide overall program administration and oversight); (3) insufficient scientific/technical data to support development of better remediation practices (i.e., data linking specific remediation strategies to specific levels of risk reduction); and (4) inadequate financing and funding (both with regard to the costs of remediation to individuals and overall program funding).
Appropriate Measures and Data Process measures include the number of drivers who are identified with various functional impairments and the licensing disposition of those drivers who are referred for remediation.

Measures of program effectiveness would include the final disposition status of drivers referred for remedial assistance, and any available driving performance or crash measures for these drivers, for comparison with either control groups or with drivers not involved in the program.
Associated Needs Associated needs include an active MAB or similar advisory capability and collaborations within the local community with potential service providers.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues This strategy benefits from an active MAB to help define appropriate policies and procedures with regard to remediation of identified impairments and from collaborations with the private sector to provide needed remedial services.
Issues Affecting Implementation Time Time requirements for implementing the strategy can vary depending upon the current status and role of the MAB, the existence and completeness of available guidelines, and prior experience in collaborating with the private sector. The strategy might initially be piloted within one or two communities.
Costs Involved Costs would vary highly depending upon the particular program components.
Training and Other Personnel Needs These needs would vary depending on the particular program components, but should be minimal (assuming that most of the more in-depth evaluation and remedial services are provided by the private sector rather than department of motor vehicles staff).
Legislative Needs None identified.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

The Maryland Research Consortium profiled in Appendix 13 is strongly committed both to identifying at-risk drivers and to providing remediation and counseling where needed. The goals of its Remediation and Counseling Contributions to Safe Mobility Working Group were to (1) provide a mechanism to refer and place at-risk individuals in appropriate remedial treatments and track treatment outcomes; (2) remediate older drivers whose functional disabilities are correctable; (3) counsel older drivers faced with restriction or cessation of driving; and (4) identify mechanisms to fund evaluation, training, rehabilitation, equipment purchase, and counseling services regarding maintaining safe mobility. Another working group of the consortium addressed mobility options for individuals facing driving restriction or cessation.

Below are examples of programs offering more in-depth driver remediation services that may or may not be linked to departments of motor vehicles:

  1. The Tampa Bay Regional Planning Council’s “Getting in Gear” program (in cooperation with the Florida Department of Highway Safety and Motor Vehicles) [http://www.agingcarefl.org/services/programs/gear]
  2. The Ohio State University’s “Older Driver Evaluation Program” [http://medicine.osu.edu/geriatrics/91.cfm]
  3. The Maryville University, St Louis, “Community Mobility and Driving Rehabilitation Program”
  4. The Beth Israel Deaconess Medical Center, Boston, Massachusetts, “DriveWise” program
  5. The Orlando, Florida, “Adaptive Mobility Services, Inc.” [http://www.adaptivemobility.com/]
  6. The University of Alabama at Birmingham’s “Driver Assessment Clinic”
  7. The Sinai Rehabilitation Center, Baltimore, Maryland, “Driver Evaluation and Training Program”
  8. The Bryn Mawr Rehab Hospital, Malvern, Pennsylvania, “Adapted Driving Program” [http://www.mainlinehealth.org/br/article_625.asp]
  9. The Penn State Rehabilitation Center, Hershey, Pennsylvania, “Driver Evaluation and Training Program” [http://www.hmc.psu.edu/rehab/services/mobility.htm]

Objective 3.1 D—Improve the Driving Competency of Older Adults in the General Driving Population

Strategy 3.1 D1: Establish Resource Centers within Communities to Promote Safe Mobility Choices (T)

General Description

The decision to stop driving is seldom easy for older adults. Driving offers a level of freedom and independence not generally afforded by other transportation modes, and the older adult who is still capable of driving is felt to be competent and self-sufficient. Family members also struggle with the decision about whether older parents should stop driving and how the older parents will get places if they do stop driving. In most cases, there is no place to turn for advice or assistance or even for encouragement and support.

One solution that has evolved from a series of focus groups conducted in states and communities across the nation is to provide a “one-call-does-it-all” telephone number that older adults or their family members can access for assistance. Working the “one-stop hotline” are trained mobility managers who can provide guidance and assistance with all aspects of driving and transportation for seniors. The mobility managers provide information and materials to help the older adult make appropriate decisions about continuing or stopping driving and are trained to make referrals where appropriate for driving evaluations, driver rehabilitation and training, vehicle modification, etc. They are also knowledgeable about transportation options within a local community and about all aspects of trip planning. While many states and local areas may maintain lists of available transportation services, what seems to be missing is a personal mobility manager to help older adults access these services.

At the state level, the one-stop hotline can be housed within the department of motor vehicles or the state office on aging. Locally, it can be housed at driver license offices, at area agencies on aging, or even senior centers. Since many of the services and referrals are at the local level, one approach to offering such one-stop shopping is to have the actual hotline operate out of local offices, but have these programs supported by the various state agencies. For example, the state motor vehicle department makes information available on medical conditions, driving record, driver evaluation, driver training, and driver rehabilitation options; the transportation or transit department provides information about alternative transportation options; and the office on aging assists with accessing transportation services locally. Programs can operate with some paid staff, but also use volunteers, especially at the local level. The overall goal of such programs is to assist older adults in continuing to drive as long as they can do so safely and in maintaining their mobility through other options once they are no longer capable of driving. By meeting this goal, the programs increase older driver safety as well as mobility.

In New York State, the office for the aging operates a toll-free hotline number for people to call when they need assistance with an aging driver safety situation. And in Erie County, New York, an Older Driver Family Assistance Help Network is being pilot tested for families, friends, and caregivers concerned about an aging loved one who is driving at risk. The network, with a broad public and private membership, supplies information about available services, addresses challenging family situations involving at-risk older drivers, works to identify and remove barriers to accessing services, and advocates for public policy changes (see Appendix 11).

In Florida, this strategy for promoting safe mobility is being carried a step further. Rather than just hotline telephone numbers, Senior Safety Resource Centers are being pilot tested in four communities (to be expanded to six), and a business plan is being developed for making them financially viable community undertakings. The Florida Department of Highway Safety and Motor Vehicles is serving as the lead agency in this effort. The Senior Safety Resource Centers offer tiered driving assessments (including both clinical and behindthe- wheel), as well as education and counseling regarding remediation and alternative mobility options. Florida also hopes to create a mobile resource unit that will travel to urban and rural communities across the state. A Web site is planned to publicize the centers. For more information, contact Selma Sauls from the Florida Department of Safety and Motor Vehicles at 850-487-0867 or Sauls.Selma@hsmv.state.fl.us.

Another option for a safety resource center is to host “senior fun days” to familiarize older adults with available transportation alternatives. For example, seniors might be given free bus passes and assisted in taking the bus to assorted destinations. Discount coupons at the destinations could add to the incentive to explore means of transportation other than driving.

EXHIBIT V-23
Strategy Attributes for Safe Mobility Resource Centers (T)

Attribute Description
Technical Attributes
Target The target of this strategy is all older adults, and especially those who need to transition from driving to not driving.
Expected Effectiveness TA number of states and localities have some variation of the “one-stop mobility management” model in place. These are identified below. While none of the programs have undergone a comprehensive evaluation, all have demonstrated considerable success in terms of contacts made and positive feedback from older persons and, in some cases, family members as well.

Better evaluations are needed for this strategy.
Keys to Success The keys to success include strong collaboration between state and local department of motor vehicles offices and other agencies and departments interested in senior transportation issues, including area agencies on aging, social service departments, and private groups providing transportation services; feedback from the target audience in developing the program; and broad-based marketing of the program once it is implemented.

Older adults may feel threatened by resource centers associated with the department of motor vehicles, particularly if the centers offer driving evaluations and/or referrals. Therefore, it may be best to house resource centers in less threatening environments (e.g., a senior center) and make access to services confidential and/or anonymous.
Potential Difficulties It can be difficult to establish the necessary collaborations.

Adequate funding may not be available to provide the level of service desired.

At least initially, substantial public information and education efforts may be needed to publicize the resource centers.
Appropriate Measures and Data The primary process measures would be the number of contacts made to the program, volume of materials distributed, the number of referrals made, etc. (i.e., services provided).

To further evaluate program processes, information might be gathered on such matters as how the person learned about the program and how satisfied he or she was with the assistance received.

It would be difficult to directly measure any reduction in crashes associated with this strategy. However, surrogates may be used, such as the probable reduction in crashes due to individuals no longer driving or reduced levels of driving exposure.
Associated Needs Materials and resources will need to be developed. These include printed materials as well as locations where people can go for driver evaluations, training, vehicle modification, etc.

An associated public information and education effort will be needed to market the service.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues This strategy depends upon cooperation between the state motor vehicle department and other agencies that might be more closely linked to transportation service providers as well as medical and rehabilitation facilities.
Issues Affecting Implementation Time Relationships with other departments and agencies and availability of existing resources will affect the implementation timeframe.
Costs Involved Some costs would be associated with developing necessary program materials, publicizing the program, and training individuals to run the program. There may also be significant costs in staffing and housing the program, although volunteers might provide at least some staffing at the local level.
Training and Other Personnel Needs See above. All program staff and volunteers would require some training in order to administer the program.
Legislative Needs Although not required, supporting legislation can be beneficial to such a program.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

Example programs related to this strategy include the following:

  1. New York State’s “Help Network” initiative, building on the state’s “When You Are Concerned” handbook. A demonstration project in Buffalo/Erie County has involved more than 20 community agencies. The goal is to identify a lead agency in each county to serve as the initial point of contact for age-related driving questions. For further information on the Erie County Help Networks program, go to http://www.erie.gov/depts/seniorservices/driving.phtml.
  2. Florida’s Senior Safety Resource Centers, supported by the Florida Department of Highway Safety and Motor Vehicles and the Florida At-Risk Driver Council. For further information, contact Selma Sauls at 850-487-0867 or via e-mail at Sauls.Selma@hsmv.state.fl.us.
  3. The “Getting in Gear” program offered by the Tampa Bay Regional Planning Council/ Area Agency on Aging (now part of the Florida Senior Safety Resource Centers). Information available at http://www.agingcarefl.org/services/programs/gear.
  4. The Beverly Foundation’s “Supplemental Transportation Programs (STPs) for Seniors” program designed to expand the use of community-based STPs (see http://www.seniordrivers.org/STPs/).

In addition, sample materials that might be used at such resource centers include the following:

  1. P. R. LePore. When You Are Concerned. 2000. [Available online at http://aging.state.ny.us/caring/concerned/index.htm]
  2. The Hartford Group. At the Crossroads: A Guide to Alzheimer’s Disease, Dementia & Driving. 2000. [Available online at http://www.thehartford.com/alzheimers/]
  3. The Beverly Foundation. Supplemental Transportation Programs for Seniors. AAA Foundation for Traffic Safety. 2001. [Available online at http://www.seniordrivers.org/STPs/]
  4. NHTSA. Adapting Motor Vehicles for People with Disabilities (brochure). [Available online at http://www.nhtsa.dot.gov/cars/rules/adaptive/brochure/index.html]

Strategy 3.1 D2: Provide Educational and Training Opportunities to the General Older Driver Population (T)

General Description

The vast majority of older drivers will not have medical conditions or functional impairments that significantly impair their driving abilities. They will not come to the attention of licensing authorities and not require the assistance of driver rehabilitation specialists. Nevertheless, their risk of crashing may be increased because of the normal physiological changes that accompany aging, including slower reaction times, poorer nighttime vision, reduced depth perception, reduced visual contrast sensitivity, and reduced ability to divide attention.

There are a number of available options for educating and training the overall population of older drivers. The most obvious is a “refresher” driving class, such as the AARP’s Driver Safety Program (formerly 55-Alive), the American Automobile Association’s (AAA’s) Safe Driving for Mature Operators Program, or the National Safety Council’s Coaching the Mature Driver Program. These courses typically involve 6–10 hours of classroom instruction and include such topics as current traffic laws and regulations, traffic situations that pose special problems for older drivers, defensive driving skills, the effects of aging on driving, and ways older adults can compensate for these changes. The AARP’s course is by far the most popular, with over 8 million drivers having taken it since 1979. Still, this translates into only a small fraction of all older drivers on the roadway. More importantly, courses such as these have not been shown to have significant safety benefits in terms of reduced crashes (although they may increase drivers’ comfort level and in some cases their overall driving exposure).

A potentially attractive, although more costly, alternative is the combining of classroom instruction with a behind-the-wheel driving evaluation and, if needed, follow-up training. This approach has been taken by the Traffic Improvement Association of Oakland County, Michigan, in updating and expanding its AAA-based course. A similar program has been sponsored by the Connecticut AAA. Although these courses are more expensive to offer because of the added one-on-one driving time, they have generated very positive comments from participants. They have not, however, been implemented on a large enough scale to allow for formal evaluation of their safety and mobility benefits.

There is also a growing body of materials designed to help older adults “self-evaluate” their driving abilities. A recent example is the “Driving Decisions Workbook” developed by researchers at the University of Michigan Transportation Research Institute (Eby et al., 2000; see Appendix 15). The Pennsylvania Department of Transportation also developed a booklet entitled, “Driving Safely As You Get Older: A Personal Guide” for distribution at driver’s license offices (Decina et al., 1999). “Drivers 55+: Check Your Own Performance” is available on the AAA Foundation for Traffic Safety Web site (http://seniordrivers.org/).

There is also some evidence that increased physical fitness and joint flexibility can improve the performance of older adults behind the wheel. The AAA Foundation Web site contains descriptions of exercises that can help older adults improve their range of motion. The Web site includes videos demonstrating the exercises.

Older driver safety materials of a more general nature have been developed by a wide variety of agencies and organizations in both the public and private sectors. While it is unlikely that these materials by themselves are directly responsible for reductions in crashes, they do serve to increase public awareness of issues affecting older drivers and steps that can be taken to increase safety.

State motor vehicle departments and driver license offices can make materials and information available on their Web sites and at local driver licensing offices. Materials can also be made available to other agencies and organizations (area agencies on aging, senior centers, etc.) having regular contact with older adults. At a more personal level, driver licensing examiners can be encouraged to attend gatherings of seniors to speak on issues affecting older adults.

EXHIBIT V-24
Strategy Attributes for Educating and Training the General Older Driver Population (T)

Attribute Description
Technical Attributes
Target The target of this strategy is the general population of licensed older drivers (and the overall driving population as well).
Expected Effectiveness While some evaluations have been performed, much more is needed before the effectiveness of these methods can be quantified.

Classroom “driver refresher” courses have generally not been shown to significantly reduce crash risk among program participants. A 1994 report by the California Department of Motor Vehicles concluded that completion of a Mature Driver Improvement course was not associated with a reduction in crashes (Janke, 1994). The more comprehensive driver refresher courses incorporating actual on-road driving have received very positive feedback from participants (Stuart Packard and Associates, 1999), but have not been implemented and evaluated on a broad enough scale to assess changes in crash risk.

Efforts to increase general public awareness about aging driver issues have generally not been evaluated in terms of safety impact. However, there have been efforts to assess public response to the materials. In Pennsylvania, a research study is being carried out to determine how many older adults read and responded to their “Driving Safely As You Get Older” booklet, mailed to 3,000 drivers.

Eby et al. (2000) developed an older driver self-evaluation instrument and were able to show that it increased older adults’ general knowledge and self-awareness and was perceived as a useful tool for generating discussions within the families of older drivers.
Keys to Success The primary key to success is getting older adults to participate in the available programs and/or to use the available materials. Programs need to be made widely available and be extensively marketed to the older driver population. Materials also need to be made widely available through avenues other than the department of motor vehicles, such as senior centers, churches, councils on aging, etc.
Potential Difficulties The greatest difficulty would appear to be the costs involved in either creating or distributing appropriate materials and programs, as well as marketing these on a large-scale basis to the driving public.
Appropriate Measures and Data Process measures of program effectiveness include the number of drivers participating in the various programs, number of program materials distributed, etc.

Measures of effectiveness might include survey data on changes in driving habits, adaptations to reduced abilities, increased knowledge of driving rules and regulations, etc. More direct crash-related measures might be used to compare “time-to-next-crash” or “-citation” (i.e., recidivism measures) for those exposed to the program/materials, vs. a control group.
Associated Needs Familiarity with existing materials and programs.
Organizational and Institutional Attributes
Organizational, Institutional, and Policy Issues Most of the available programs and materials have been privately developed. Thus, there may be policy issues involved in state agencies recommending and using such programs and materials.
Issues Affecting Implementation Time This is assumed to be an ongoing, long-term strategy.
Costs Involved There would be costs involved in developing any needed materials, printing or producing the materials, and marketing the program to the driving public. These costs could be highly variable depending on the nature of the materials and the size of the target audience.
Training and Other Personnel Needs None identified.
Legislative Needs None identified.
Other Key Attributes
None identified.

Information on Agencies or Organizations Currently Implementing this Strategy

Pennsylvania distributes its “Driving Safely As You Get Older: A Personal Guide” at driver licensing offices statewide. The guide presents simple tests to help drivers be aware of changes in their physical or mental abilities that are likely to increase their risks when driving and identifies things older drivers can do to keep driving safely. For information on availability of the guide, contact PennDOT.

The New York State Office for the Aging produced “When You Are Concerned: A Guide for Families Concerned about the Safety of an Older Driver” and makes copies of this available upon request. Report copies can also be downloaded from the web [http://www.aging.state.ny.us/caring/concerned].

Florida distributes a wide variety of safety materials through its Senior Safety Resource Centers. Included is the booklet, “Is it Time to Stop Driving? Plain Talk About Driving and Memory Problems,” prepared by Ruth Tappen and Kathleen Jett at Florida Atlantic University.

Maryland DOT helped to develop “Driving Safely While Aging Gracefully” for distribution at driver license offices. [http://www.nhtsa.dot.gov/people/injury/olddrive/Driving%20Safely%20Aging%20Web/index.html]

Oregon DOT’s “Shifting Gears in Later Years” program (see Appendix 12) makes many resources available to older drivers and their families (see http://www.oregonsafemobility.org/). Also, Oregon State University, with the Pacific Northwest Extension System, produced “Driving Decisions in Later Life,” (see http://extension.oregonstate.edu/harney/FCD/driving_decisions.html) entitled “Keeping the Keys—Mobility, Freedom, Choice.” Information on both can be obtained from the Chicago Traffic Center, telephone 312-603-2600.

The Hartford Group publishes At the Crossroads: A Guide to Alzheimer’s Disease, Dementia & Driving. 2000 [available online at http://www.thehartford.com/alzheimers/].

Many private groups (AAA, AARP, Alzheimer’s Association, State Farm Insurance, etc.) make materials available to the public and may allow distribution through state department of motor vehicles offices. In addition, the following materials are available from NHTSA:

  1. “Safe Driving for Older Adults” [http://www.nhtsa.dot.gov/people/injury/olddrive/OlderAdultswebsite]
  2. “Driving Safety While Aging Gracefully” [http://www.nhtsa.dot.gov/people/injury/olddrive/Driving%20Safely%20Aging%20Web/index.html]
  3. A series of three pamphlets for driving with macular degeneration, glaucoma, and cataracts.

Objective 3.1 E—Reduce the Risk of Injury and Death to Older Drivers and Passengers Involved in Crashes

Strategy 3.1 E1: Increase Seatbelt Use by Older Drivers and Passengers (P)

General Description

As noted in the overall description of the problem, the increased risk of older persons dying in crashes may be as much a result of their increased fragility as increased propensity to accidents. Compared with younger drivers, older drivers are four times more likely to die in a crash. This is despite the fact that their crashes generally occur at lower speeds and are less likely to involve alcohol, speed, and other exacerbating factors.

The auto industry has only recently begun paying attention to the special needs of a growing population of increasingly fragile drivers and passengers. But it will be many years before the changes being designed into new automobiles to better protect older drivers (and, in fact, all drivers) significantly affect the numbers of older adults dying on U.S. highways. In the meantime, getting every older driver and passenger to buckle up is a solution that can have an immediate and dramatic impact.

Seatbelt use is already high among this age group—according to the 2002 National Occupant Protection Use Survey, an estimated 82 percent of adults age 70 and older buckle up, compared with an overall population estimate of 75 percent (see Glassbrenner, 2003, for the 2003 survey results). Because the use rate is so high, agencies and organizations that typically have been involved in efforts to promote seatbelt use may be inclined to focus their efforts elsewhere. This, however, is a mistake if the goal is to reduce overall traffic fatalities. Exhibit V-25 shows that among belted occupants, the ratio of traffic fatalities to injuries remains fairly flat, rising only slightly in the oldest age groups. However, among unbelted occupants, there is a steep rise in the number of fatalities per 1,000 injuries beginning at about 55 years of age. Getting older drivers and passengers to buckle up can dramatically reduce their likelihood of dying in a crash.

EXHIBIT V-25
Fatality to Injury Ratios for Belted and Unbelted Occupants, 1999
(Source: Wagner and Gotschall, 2002)

To be most effective, efforts to increase seatbelt use among older drivers and passengers should be specially targeted to these populations. Example approaches might include educating physicians to talk to their older patients about the importance of always wearing their seatbelt and informational brochures that could be distributed through local senior centers, churches, etc. While enforcement efforts targeting older adults may not be appropriate, passage of a primary seatbelt law could prove especially beneficial in persuading the remaining noncompliant older adults to buckle up.

While seatbelt education and promotion programs have not been directed specifically at older drivers, there is enough evidence from the programs directed at the general population to suggest that a special effort of this type will be effective. However, evaluations of such specific programs are needed. The companion guide on increasing seatbelt use provides additional details.

Information on Agencies or Organizations Currently Implementing this Strategy

No state or local efforts have been identified that have specifically targeted older adults for increased seatbelt use.

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