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Allan F Williams

Publications and source records attributed to Allan F Williams.

29 records · Page 2Linked to original sources
PubMed2003

Specific and long-term effects of Nova Scotia's graduated licensing program.

A graduated licensing (GL) program was introduced in Nova Scotia, Canada, in October 1994. Previous research has shown that it reduced collisions in the short term. The present study examined the relative contribution of each stage of the program (i.e., learner and intermediate levels) and the program's impact after beginning drivers graduated to full licensure. The research focused on teenage beginning drivers (age 16-17), but the effects on older beginners also was examined. Per-driver crash rates of two groups of novices selected from driver records in Nova Scotia were compared. One group (pre-GL) received their learner's permits during the 2 years before the program was implemented, and the second group (GL) received their learner's permits during the 2 years after implementation. The findings clearly establish that most of the collision reduction in Nova Scotia's program occurred during the first year of the program, particularly during the first 6 months when the majority of novices were driving under supervision. The collision rate for 16 to 17-year-old GL novices was 50% lower than the rate for pre-GL novices during the 6 months after they received their learner's permits, and about 10% lower during their first 2 years of licensure when unsupervised driving from midnight to 5 A.M. was prohibited. Much of this improvement for 16 to 17-year-olds occurred during restricted night hours. Collision rates also were lower during nonrestricted hours in the initial 6 months of licensure. The 3-month "time discount" for driver education provided no safety benefit, and GL novices with driver education had collision rates that were not lower than pre-GL novices. There was no long-term effect found for the program after 16 to 17-year-olds graduated to full licensure. For older beginning drivers, crash rates during the first year after obtaining a learner's permit showed a 31% reduction. This effect diminished rapidly. There was only a 2% reduction during the first year of licensure, and crash rates increased during the following 2 years. Overall the data indicate substantial benefits of graduated licensing for 16 to 17-year-old beginners, but no benefits beyond the learner stage for older beginners.

Accidents, Traffic↗
PubMed2003

Drivers' assessment of Ford's belt reminder system.

In recent model years, Ford vehicles have been equipped with a supplementary seat belt reminder system that flashes and chimes intermittently for up to 5 min if the driver is unbelted. Sound- and light-based belt reminder systems of various types are beginning to appear in the market place, and it is important to learn about their acceptance and ability to increase belt use. The present study was designed to ascertain consumer reaction and reported belt use regarding the Ford system. Personal interviews were conducted with 405 drivers of vehicles with the reminder system. Among the drivers, 67% said they had activated the belt reminder one or more times, 73% said that the last time this happened they fastened their belts, 46% said their belt use had increased since driving this vehicle, 78% said they liked the reminder system, and 79% said they wanted a reminder system like this in their next vehicle. Five percent had disabled the system. Part-time users were responsive to the reminder, for example, of those who said they currently used belts usually but not on some occasions, 70% said they fastened their seat belts the last time the reminder was activated and 76% said their belt use had increased. Five percent spontaneously mentioned the belt reminder as an especially disliked feature of their new vehicles, and 2% said their belt use had decreased since having it. The 7% of respondents who reported they used belts never or very occasionally were least responsive to the system. Overall, the Ford belt reminder system is being favorably received.

Accidents, Traffic↗
PubMed2002

Changes in crash risk following re-timing of traffic signal change intervals.

More than I million motor vehicle crashes occur annually at signalized intersections in the USA. The principal method used to prevent crashes associated with routine changes in signal indications is employment of a traffic signal change interval--a brief yellow and all-red period that follows the green indication. No universal practice exists for selecting the duration of change intervals, and little is known about the influence of the duration of the change interval on crash risk. The purpose of this study was to estimate potential crash effects of modifying the duration of traffic signal change intervals to conform with values associated with a proposed recommended practice published by the Institute of Transportation Engineers. A sample of 122 intersections was identified and randomly assigned to experimental and control groups. Of 51 eligible experimental sites, 40 (78%) needed signal timing changes. For the 3-year period following implementation of signal timing changes, there was an 8% reduction in reportable crashes at experimental sites relative to those occurring at control sites (P = 0.08). For injury crashes, a 12% reduction at experimental sites relative to those occurring at control sites was found (P = 0.03). Pedestrian and bicycle crashes at experimental sites decreased 37% (P = 0.03) relative to controls. Given these results and the relatively low cost of re-timing traffic signals, modifying the duration of traffic signal change intervals to conform with values associated with the Institute of Transportation Engineers' proposed recommended practice should be strongly considered by transportation agencies to reduce the frequency of urban motor vehicle crashes.

Accidents, Traffic↗
PubMed2002

Drinking and driving among Mexican American and non-Hispanic white males in Long Beach, California.

Although drinking and driving in the United States has declined substantially during the past two decades, this trend has not been seen among Hispanic drivers. Higher rates of driving while impaired (DWI) arrests and alcohol-related crashes, particularly among Mexican Americans, also have been noted. The extent to which this reflects a lack of understanding of DWI laws rather than a disregard for them is unknown. A survey was conducted among Mexican American and non-Hispanic white male DWI arrestees in Long Beach, California, to ascertain alcohol use, attitudes toward drinking and drinking and driving, and knowledge of DWI laws. The findings were compared with those of Mexican American and non-Hispanic white males recruited from the local community. Mexican American males, both DWIs and those from the community, reported heavier drinking than non-Hispanic white males. All four groups of respondents tended to underestimate the number of drinks needed to achieve the blood alcohol concentration (BAC) threshold at or above which it is illegal to drive under California law. Estimations were around 2-3 drinks rather than a more realistic estimate of 4-5 drinks. However, Mexican American DWIs and their comparison group vastly overestimated the number of drinks to make them unsafe drivers (8- 10 drinks). Furthermore, fewer than half were aware of the BAC threshold in California (0.08%) compared with between 60 and 78% of non-Hispanic whites. This study is limited in scope and needs to be replicated in other communities and with other racial/ethnic groups. However, the clear lack of knowledge of the DWI law in California and a lack of understanding of the relationship between number of drinks and BAC point to the need for culturally sensitive programs that are developed and implemented within the Mexican American community.

Accidents, Traffic↗
PubMed2002

Seat belt use among African Americans, Hispanics, and Whites.

OBJECTIVES: This study investigated seat belt use among White, Black, and Hispanic drivers, in cities in which standard enforcement of the belt use law is permitted (primary enforcement) and in cities in which a motorist has to be first cited for another offense (secondary enforcement). Socioeconomic and gender differences in belt use were also studied. METHODS: Belt use observations were obtained at gas stations in Boston, Chicago, Houston, and New York City. In short interviews with drivers, information on race/ethnicity and education was obtained. RESULTS: Belt use was higher in primary enforcement cities, among women, and among those with at least a college degree. In primary law cities there were no clear differences in belt use by race/ethnicity; in secondary cities African Americans were less likely than Whites or Hispanics to be belted, among populations both with and without college degrees. This is consistent with data from other studies indicating that African Americans are more sensitive than Whites to the enforcement of primary laws and are more likely to increase belt use when states shift from secondary to primary. There has been no evidence of enforcement bias against African Americans--increases in citations generally have been greater among Whites than African Americans once primary enforcement is implemented. CONCLUSIONS: More widespread application of primary laws--standard throughout the world but in only 17 US states and the District of Columbia--would increase belt use for all drivers, especially African Americans.

Black or African American↗
PubMed2002

Pedestrian crashes in Washington, DC and Baltimore.

Police crash reports were obtained for pedestrian-motor vehicle crashes in Washington, DC (N = 852) and Baltimore (N = 1234) for the year 1998. Reports were coded using procedures developed and applied in these two cities during the 1970s, including the determination of pedestrian crash type, primary precipitating factor, and culpability. Results indicated substantial differences between crash patterns observed during the 1970s and those observed during 1998. Midblock dart-dash crashes, which typically involve a precipitating factor or critical error by a child pedestrian, decreased (from 37% to 15% in Washington). Across all crashes in both cities, the number of drivers who made a critical error leading to the crash was nearly equivalent to the number of pedestrians who made a critical error. Overall, pedestrians were slightly more likely to be judged culpable (50% vs. 39%). Turning vehicle crashes, which typically involve a driver's failure to grant a pedestrian the right of way at a signalized intersection, increased (from 9% to 25% in Washington). Countermeasures to reduce the number of pedestrians hit by turning vehicles are discussed.

Accidents, Traffic↗
PubMed2002

Responses of teenagers and their parents to California's graduated licensing system.

In 1998, California adopted a strong graduated licensing system that lengthened the learner's permit stage from 1 month to a mandatory 6 months and introduced passenger and nighttime restrictions for initial license holders. The passenger restriction (no passengers younger than 20 for the first 6 months) is stronger than such restrictions in any other state; the nighttime ban is relatively weak, not beginning until midnight. Surveys were undertaken to learn what teenagers and their parents thought about the new requirements and how they responded to them. Two groups of beginning California license holders were surveyed three times during the first year of licensure; their parents were interviewed twice. One group (n = 543) was subject to the graduated licensing requirements, the other (n = 814) was not. Parents strongly endorsed the new system. The vast majority approved of the new permit requirements and the nighttime and passenger restrictions. Among parents whose children were subject to the new requirements, 79% were strongly in favor of the new system and only 4% were neutral or opposed. Teenagers were less favorable toward the new requirements. Most approved of the new learner's permit rules, and the majority of teenagers favored the night restriction, but only about one-third endorsed the passenger restriction. Compliance with the new rules was not close to universal, but the new licensing system resulted in young people holding their learner's permits longer, accumulating more practice driving prior to licensure and decreased the amount of reported driving after midnight and transportation of teenagers when initially licensed. Most teenagers subject to the new rules said they were able to do the activities they wanted despite the changes; almost three-quarters said they were not affected much by either the nighttime or passenger restriction. Overall the results indicate that the new licensing system is accepted favorably by teenagers and their parents and has substantially increased the types of behaviors that collectively should lead to crash and injury reductions.

Accidents, Traffic↗
PubMed2002

Awareness of zero tolerance laws in three states.

PROBLEM: A prior study indicated that zero tolerance laws differ in their enforceability and likelihood of enforcement, with California's law being easier to enforce than New York's, and New Mexico's being the hardest of all. The question is, do these differences in enforcement affect teenagers' knowledge and perception of these laws? METHOD: A telephone survey was conducted to investigate awareness of the laws among 17-20 year olds in these three states and perceptions of enforcement. RESULTS: Estimated percentages of teenagers who knew of the laws were much higher in New York and California (71% and 65%, respectively) than in New Mexico (34%). Perceptions that police were enforcing the law, that licenses could be suspended, and that penalties were often applied were also lowest in New Mexico. IMPACT ON INDUSTRY: The potential of zero tolerance laws will not be realized without better awareness among young people. Full enforcement of the laws accompanied by publicity about the enforcement is recommended. Changes to the laws and their application may encourage enforcement efforts.

Adolescent↗
PubMed2002

Graduated licensing for teens: why everybody's doing it.

While the United States traditionally has allowed quick and easy paths to full-privilege licensure of drivers at an early age, graduated licensing is becoming increasingly popular. The graduated licensing system phases in unrestricted driving by allowing beginners to get their initial behind-the-wheel experiences under conditions that reduce the risk of collision. As of June 2002, 35 states and the District of Columbia had enacted some sort of graduated licensing law. Recent evaluations of graduated licensing systems in four states have found reductions in crashes among 16-year-old drivers ranging from 11 to 33 percent. Yet, not all states have such laws, and many of the graduated licensing systems in use lack important provisions, such as nighttime driving and passenger restrictions. This article reviews the rules, restrictions, and provisions of the graduated licensing model; discusses evaluations of graduated licensing systems; identifies and analyzes variations in graduated licensing approaches across states; assesses the successes and failures of early graduated licensing laws, using New Mexico as an example; and discusses the potential of these systems to prevent injuries.

Accidents, Traffic↗