Traffic environment and demographic factors affecting impaired driving and crashes.

Introduction: Data availability has forced researchers to examine separately the role of alcohol among drivers who crashed and drivers who did not crash. Such a separation fails to account fully for the transition from impaired driving to an alcohol-related crash.

Method: In this study, we analyzed recent data to investigate how traffic-related environments, conditions, and drivers' demographics shape the likelihood of a driver being either involved in a crash (alcohol impaired or not) or not involved in a crash (alcohol impaired or not).

The Long Beach/Fort Lauderdale relative risk study.

Problem: The role of alcohol as a major factor in traffic crash causation has been firmly established. However, controversy remains as to the precise shape of the relative risk function and the BAC at which crash risk begins to increase.

Methods: This study used a case-control design in two locations: Long Beach, California, and Fort Lauderdale, Florida.

Evaluation of a high visibility enforcement project focused on passenger vehicles interacting with commercial vehicles.

Introduction: In 2004, Washington State applied NHTSA's High Visibility Enforcement model used in the Click It or Ticket seat belt campaign in an attempt to reduce unsafe driving behaviors around commercial motor vehicles (CMVs). The program was called Ticketing Aggressive Cars and Trucks (TACT). This paper details the methods used to evaluate the program's effectiveness and the results of the evaluation.

The relationship between blood alcohol concentration (BAC), age, and crash risk.

Problem: The role of age (youth and driving inexperience) and alcohol as major risk factors in traffic crash causation has been firmly established by numerous studies over the past 50 years. Less well established is how the two variables interrelate to influence crash risk. Some investigations have hypothesized an interactive or synergistic effect in which young drivers with less experience and a greater tendency to take risks are more adversely affected at lower blood alcohol concentrations (BACs) than are older drivers.

Problem driver remediation: a meta-analysis of the driver improvement literature.

Problem: Given the public safety risk posed by violation and crash repeaters and the substantial costs for state driver improvement programs, it is important that their effectiveness be scientifically demonstrated and that intervention programs are based on sound research findings.

Method: Crash and traffic violation standardized effect sizes (d) representing 106 individual interventions were coded from 35 methodologically sound studies and analyzed using meta-analysis.

Results: Driver improvement intervention in general was associated with small but significant reductions in both crashes (dw = 0.

Using traffic conviction correlates to identify high accident-risk drivers.

One of the primary missions of the California Department of Motor Vehicles is to protect the public from drivers who represent unacceptably high accident risks. Optimum fulfillment of this objective requires the development and implementation of strategies for identifying high-risk drivers. One such system in California is the department's negligent operator point system.

Graduated driver licensing and safer driving.

Graduated Driver Licensing (GDL) inserts between the leaner permit and full licensure an intermediate or "provisional" license that allows novices to drive unsupervised but subject to provisions intended to reduce the risks that accompany entry into highway traffic. Introduction of GDL has been followed by lowered accident rates, resulting from both limiting exposure of novices to unsafe situations and by helping them to deal with them more safely. Sources of safer driving include extended learning, early intervention, contingent advancement, and multistage instruction.