Research Studies & Reports

DMV’s Research & Development Branch has been conducting research and producing studies and reports since the 1950s. Research & Development reports help DMV to measure the impact of new laws on making drivers safer. We also identify areas where we can improve our processes, explore new approaches to solving existing problems, and branch out into new opportunities to serve you better. 

Request printed copies of studies and reports by mail at:

Department of Motor Vehicles
Research and Development Branch
2415 1st Ave. Mail Station: F-126
Sacramento, CA 95818
(916) 914-8125

Please include the report number, the number of copies requested, and your name, address, and phone number.

393 Results

Report ID Date Published Title Section Links
153 1995/ 05

NEGLIGENT-OPERATOR TREATMENT EVALUATION SYSTEM

By: William C. Marsh and Erin J. Healey

This report is the last in a series which originally began with the creation of the Post Licensing Control Reporting and Evaluation System (PLCRES) in 1976 and extended in 1983 by a modified version of that system (Negligent Operator Treatment Evaluation System). The present report is being issued as an internal technical report of the Department of Motor Vehicles' Research and Development Section rather than an official report of the State of California. The findings and opinions may therefore not represent the views and policies of the State of California.

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154 1995/ 08

An Evaluation of the Validity of California’s Driving PerformanceEvaluation Road Test

By: Patricia A. Romanowicz and Robert A. Hagge

This report presents findings of an evaluation of the validity of the Driving Performance Evaluation(DPE) road test that was piloted in 30 California Department of Motor Vehicles field offices. Thestudy represents the fourth stage in a four-stage project to develop an improved competency-baseddrive test for possible statewide implementation. The DPE was found to have construct validity asdemonstrated by experienced good drivers having had significantly lower fail rates and mean pointscores than did inexperienced drivers and drivers with physical or mental disabilities that affected theirdriving. The evaluation also found the DPE to be more difficult than the current drive test, with failrates of 45.6% and 26.2% for the two tests, respectively. The DPE was also found to take 11 minuteslonger to administer than did the current drive test. The impact on test validity of severalmodifications to shorten the DPE test time was also evaluated.

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155 1995/ 08

California’s Negligent Operator Treatment Program Evaluation System, 1976-1995 (An Overview of Findings and Program Improvements)

By: Raymond C. Peck and Erin J. Healey

This report represents a chronological review of an evaluation system which was initiated in the early 1970's and which was terminated at the end of 1994. Originally known as the Post Licensing Control Reporting and Evaluation System (PLCRES ) and later as the Negligent Operator Treatment Evaluation System (NOTES), it produced a large number of evaluation reports over the period 1976-1995. In 1982, departmental research staff received the National Highway Traffic Safety Administration's Award of Honor in recognition of the contributions of PLCRES reports to evaluation research literature.

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156 1994/ 07

AGE-RELATED DISABILITIES THAT MAY IMPAIR DRIVING AND THEIR ASSESSMENT

By: Mary K. Janke

This review, covering literature on age-related disabilities, their assessment, and their effects on driving, represents the initial step in developing an assessment system for identifying and evaluating the driving competency of older drivers with dementia or age-related frailty. Since frailty can be defined as a result of the combined effect of various pathologies superimposed upon the normal physiological changes of aging, emphasis is given to medical conditions which are more characteristic of elderly people. The relationships of these conditions to driving performance and safety are discussed, and nondriving and driving tests relevant to identifying and licensing frail or dementing elderly are described. There is a brief discussion of licensing and post-licensing control programs for elderly drivers in several jurisdictions, including graded licensing. A preliminary assessment protocol for identifying medically impaired elderly drivers and evaluating their driving ability is suggested.

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157 1995/ 12

Evaluation of Mature Driver Improvement Program Home-StudyCourses

By: Eric Berube

This report compares the effectiveness of home-study and in-person courses offered underCalifornia's mature driver improvement (MDI) program. The major issue addressed inthe report is whether home-study MDI courses are less effective than in-person courses inreducing fatal/injury crashes and total citations. Two secondary issues are (a) the validityof MDI course completion as an indicator of fatal/injury crash risk and (b) whether MDIcourses themselves reduced fatal/injury crash risk. The study results provide littleevidence that home-study courses are less effective than in-person courses in reducingfatal/injury crashes and total citations, and no evidence that MDI course graduates are atactuarially lower fatal/injury crash risk than are nonparticipants. In addition, the resultsindicate that the MDI program may have reduced the rate of traffic violation citations,but not the rate of fatal/injury crashes, among course graduates.

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158 1995/ 09

The General Deterrent Impact of California’s 0.08% Blood Alcohol concentration Limit and Administrative Per Se License Suspension Laws

By: Patrice N. Rogers

This project evaluated the effects of two new driving-under-the-influence (DUI) laws implemented in California. The first law, effective January 1, 1990, reduced California’s illegal per se limit to 0.08% blood alcohol concentration (BAC) and the second, effective July 1, 1990, imposed an administrative per se (APS) pre-conviction license suspension on DUI offenders. Intervention time series analysis was used to evaluate the deterrent impact of these laws on the general population of DUI offenders as measured by the effects on alcohol-related traffic accidents.

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159 1996/ 01

1996 ANNUAL REPORT OF THE CALIFORNIA DUI MANAGEMENT INFORMATION SYSTEM

By: Helen N. Tashima and Clifford J Helander

In this fifth annual report, 1993 and 1994 DUI data from several diverse sources were compiled and cross-referenced for the purpose of developing a single comprehensive DUI data and monitoring system. This report presents crosstabulated information on DUI arrests, convictions, court sanctions, administrative actions and alcohol-involved accidents. In addition, this report provides an evaluation of the effectiveness of alternative court and administrative sanctions (including alcohol treatment programs and license actions) upon the postconviction records of first and second DUI offenders. The postconviction driving records of DUI offenders arrested in 1989, 1991, and 1993 were evaluated for five-, three-, and one-year periods, respectively.

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160 1995/ 09

Evaluation of California’s Special Drive Test Program

By: Robert A. Hagge

This report presents results of an evaluation of the department’s special drive test (SDT) program. A totalof 407 forms used to refer drivers for an SDT and to score their performance on the test were collectedover a 2-week period in October 1993 from 82 field locations. The driver records for these subjects werealso analyzed. The results showed that the SDT had a fail rate of 31.1% and an internal-consistencyreliability of .88. The vast majority (3/4) of SDT referrals were not recommended for a license restriction(e.g., no night driving), although 96% of SDT fails were under license suspension or revocation sometimeduring the 6 months following SDT testing. The driver record analysis revealed that the 3-year prior totalaccident rate for SDT subjects was 3 times higher than that for drivers of the same age and sex in thegeneral driving population. For 3-year prior total citations, the rate for SDT subjects was nearly twice ashigh as the standardized rate for other drivers. The 3-year prior accident rate for SDT fails was notsignificantly different from that for SDT passes, but SDT fails had a significantly lower 3-year prior totalcitation rate than did SDT passes.It was concluded that (1) available treatments (e.g., license restrictions) for incompetent drivers referredfor an SDT are underutilized, (2) the SDT is not effective in discriminating between low- and high-riskdrivers, and (3) the SDT program appears to reduce accident risk for drivers who fail the test but not forthose who pass. It was recommended that a unified policy directive be developed that would address theobjective of the SDT and specify the criteria to be used for referring applicants for an SDT, scoring thetest, and translating test performance into a licensing decision.

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162 1996/ 05

Predicting DUI Recidivism. Volume 1: Blood Alcohol Concentration and Driver Record Factors

By: Leonard A. Marowitz

This study examined the relationship between BAC at arrest, driving history, and other demographic factors, and the 1-year post-arrest probability of recidivism for DUI convictees. BAC-only prediction models, complex prediction models involving many factors found on the driver record, and simple prediction models containing two or three factors were developed. All models found a third degree or cubic relationship between BAC and recidivism, and showed recidivism to be high at a BAC of 0.00%, decreasing down to a BAC of about 0.09%, increasing to a BAC of about 0.29%, and then decreasing again to a BAC of 0.35%+. High rates of recidivism at high BACs suggest alcohol dependency, while at low BACs other impairing substances are likely to be involved. The mean rate of DUI recidivism for offenders who refused to be tested for alcohol was the same as the mean rate for BAC-tested offenders who had prior DUIs at the time of the arrest.

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163 1996/ 03

AN EVALUATION OF THE TRAFFIC SAFETY RISK OF BIOPTIC TELESCOPIC LENS DRIVERS

By: Nancy Clarke

This report compares the 2-year accident and citation rates for 609 drivers who must wear a bioptic telescopic lens (BTL) device when driving with those for a randomly selected comparison group of 28,109 drivers. The criterion measures were statistically adjusted using age and gender as covariates. The results indicate that the adjusted total and fatal/injury accident rates for the BTL group were 1.9 and 1.7 times higher, respectively, than those for the comparison group. However, an opposite result was found for total citations; the adjusted rate for the BTL group was 0.7 of the adjusted rate for the comparison group on this measure. All of the differences were statistically significant. The differences in the adjusted means were even greater when only drivers with valid licenses were considered. These findings suggest that BTL drivers do not sufficiently compensate for their higherrisk status. The study also found that the department's policy of restricting BTL drivers from driving at night was followed for only 35% of the BTL subjects. The department is in the process of correcting this operational deficiency.

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