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.
Studies & Reports Sections
Studies and reports are assigned to a Section that best describes the type of report. Click on a section title below to see a short description.
I. Driver Education & Training Studies
II. Driver Licensing Screening Studies
III. Studies on Improvement and Control of Deviant Drivers
IV. Basic Research & Methodological Studies: Driver Performance, Accident Etiology, Prediction Models, and Actuarial Applications
V. Driver Licensing / Control Systems & Safety Management Studies
VI. Studies on Special Driver Populations
VII. Miscellaneous Studies & Reports
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.
| Report ID | Date Published | Title | Section | Links |
|---|---|---|---|---|
| 166 | 1995/ 05 |
Exploratory Multivariable Analyses ofCalifornia DriverRecord Accident RatesSince 1964, the California Department of Motor Vehicles has issued several monographs on driver characteristics and accident risk factors as part of a series of analyses known as the California Driver Record Study. This paper presents the results of a number of regression analyses of driving record variables measured over a 6-year time period (1986-91). The techniques presented consist of ordinary least squares, weighted least squares, Poisson, negative binomial, linear probability, and logistic regression models. T he objective of the analyses was to compare the results obtained from several different regression techniques under consideration for use in the in-progress California Driver Record Study. The results are informative in determining whether the various regression methods produce similar results for different sample sizes and to explore whether reliance on ordinary least squares techniques in past California Driver Record Study analyses have produced biased significance levels and parameter estimates. The results indicate that, for these data, the use of the different regression techniques do not lead to any greater increase in individual accident prediction beyond that obtained through application of ordinary least squares regression. In addition, the methods produce almost identical results in terms of the relative importance and statistical significance of the independent variables. It therefore appears safe to employ ordinary least squares multiple regression techniques on driver accident-count distributions of the type represented by California driver records, at least when the sample sizes are large. |
IV | |
| 165 | 1997/ 01 |
1997 ANNUAL REPORT OF THE CALIFORNIA DUI MANAGEMENT INFORMATION SYSTEMIn this sixth annual legislatively mandated report, 1994 and 1995 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 alcoholinvolved 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, 1992, and 1994 were evaluated for six-, three-, and one-year periods, respectively. |
V | |
| 164 | 1996/ 07 |
Predicting DUI Recidivism. Volume 2: The Incremental Utility of Non-Driver Record FactorsThis study determined if factors not available on the driver record are significant predictors of DUI recidivism in the presence of factors found on the driver record. The first substudy focused on alcohol assessment factors, while the second substudy focused on demographic and life-style factors. Alcohol assessment factors, including the MAST and CAGE tests, and the interviewer’s assessment of alcohol dependency, were not found to be significant predictors of 1-year DUI recidivism, while some demographic factors were found to be significant predictors. DUI recidivism was found to decrease with increasing years of education and with being employed full-time, while it increased with the number of prior alcohol or drug treatment experiences and being on active military duty status. Each substudy identified driver record factors which were also significant predictors of 1-year DUI recidivism. |
V | |
| 163 | 1996/ 03 |
AN EVALUATION OF THE TRAFFIC SAFETY RISK OF BIOPTIC TELESCOPIC LENS DRIVERSThis 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. |
VI | |
| 162 | 1996/ 05 |
Predicting DUI Recidivism. Volume 1: Blood Alcohol Concentration and Driver Record FactorsThis 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. |
V | |
| 160 | 1995/ 09 |
Evaluation of California’s Special Drive Test ProgramThis 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. |
II | |
| 159 | 1996/ 01 |
1996 ANNUAL REPORT OF THE CALIFORNIA DUI MANAGEMENT INFORMATION SYSTEMIn 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. |
V | |
| 158 | 1995/ 09 |
The General Deterrent Impact of California’s 0.08% Blood Alcohol concentration Limit and Administrative Per Se License Suspension LawsThis 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. |
V | |
| 157 | 1995/ 12 |
Evaluation of Mature Driver Improvement Program Home-StudyCoursesThis 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. |
I | |
| 156 | 1994/ 07 |
AGE-RELATED DISABILITIES THAT MAY IMPAIR DRIVING AND THEIR ASSESSMENTThis 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. |
VI |