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
2570 24th Street, Mail Station: H-126
Sacramento, CA 95818
(916) 657-5805

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

Report ID Title Section Links
181

An Evaluation of the Impact of California’s Driving PerformanceEvaluation Road Test on Traffic Accident and Citation Rates

By: Michael A. Gebers, Patricia A. Romanowicz, & Robert A. Hagge

This evaluation is the final stage of a project to develop and evaluate the driving performance evaluation(DPE) drive test for possible statewide implementation in California. This study and earlier studies in theseries are part of a more extensive effort by the department to increase the competency of Californiamotorists by improving the driver licensing process. The DPE is currently being used in over 60 fieldoffices in southern California.The effect of the DPE on accident and citation rates was determined by comparing driving records for asample of applicants taking the DPE with those of a sample of applicants taking the current drive test bothbefore and after implementation of the DPE.Logistic regression analysis was used to compare the crash and citation rates of the groups during the 2years immediately following driver license application. The findings failed to substantiate any reduction inaccident involvements or traffic law violations resulting from implementation of the program. However,there is no question that the DPE is a more reliable and content-valid test. Therefore, it is recommendedthat the DPE road test be expanded to all offices in the state.

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182

EVALUATION OF THE CLASS C DRIVER LICENSE WRITTEN KNOWLEDGE TESTS

By: Scott V. Masten

This report presents the results of an evaluation of the English DL 5 (Rev. 10/98), Spanish DL 5 (Rev. 5/98), and English DL 5T (Rev. 8/98) Class C license written knowledge examinations. Specifically, the study assessed the fail rate, mean number of errors, and internal-consistency reliability for each test form, as well as the pass rate, percentage of applicants selecting each answer choice, and item-total correlation for each item on each test form for the English tests. Also presented is an assessment of the randomness of the answer choice assignment for the English DL 5.

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196

Development and Evaluation of Revised Class C Driver LicenseWritten Knowledge Tests

By: Eric A. Chapman and Scott V. Masten

This report presents the results of an evaluation of English and Spanish language Class C license written knowledge examinations administered to applicants for an original or renewal driver licenses. The tests were extensively modified following the 1999 statewide evaluation (Masten, 1999). The study assessed the fail rate, mean number of errors, and internal-consistency reliability for each test form, as well as the pass rate, percentage of applicants selecting each answer choice, and item-total correlation for each item on each English language test form. The results are based on 10,502 completed test forms that were collected from field offices statewide in April 2001. It was found that the test fail rates for all tests decreased from the last statewide evaluation. However, the disparity in fail rates between the English and Spanish tests increased, with the rates for Spanish applicants continuing to be substantially higher than the rates for English applicants.

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205

Evaluation of California’s Graduated Driver Licensing Program

By: Scott V. Masten and Robert A. Hagge

California’s 1998 graduated driver licensing program was implemented to reduce the high crash risk of teenage drivers. Monthly per capita crash rates for 15-to-17-year-olds were analyzed using time series analysis. No overall reduction in total crashes or fatal/injury crashes was found immediately following program implementation or beginning 6 months later. The 12-month nighttime restriction was associated with significant sudden-permanent reductions of 0.44% in total crashes and marginally significant 0.45%in nighttime fatal/injury crashes. The 6-month passenger restriction was associated with reductions of 2.52% and 6.43% in total and fatal/injury teen passenger crashes, respectively. The fact that no overall reductions in crashes, and only small reductions in crashes associated with the restrictions, were found isnot surprising given findings that teens and parents were either already practicing program requirementsprior to implementation, or not fully complying with the program requirements afterwards. The findings provide support for passenger and nighttime restrictions.

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215

Clearing A Road To Driving Fitness By Better Assessing Driving Wellness:California’s Three-Tier Driving-Centered Assessment System – SummaryReport

By: David F. Hennessy and Mary K. Janke

This report describes the final development and validation of an integrated three-tier system for assessing drivers’ degrees of driving wellness (degree of freedom from driving-relevant functional limitations) and driving fitness (degree to which a driver compensates for any such limitations while actually driving). Both driving wellness and driving fitness are assessed in a driving-centered manner. Assessment tools recommended for use in each tier are described, as is the selection of two decision points (cutpoints) which separate drivers into three categories: pass ("driving-well"), "somewhat functionally limited", and "extremely functionally limited." Compared to elder renewal license applicants who were assessed as somewhat functionally limited, elder renewals assessed as extremely functionally limited were more likely to fail a structured road test, but less likely to have been crash involved in the last three years. Reasons for this apparent paradox, in which more functionally limited drivers have fewer crashes, are addressed in the report. The report describes in detail the flow of renewal license applicants through the three-tier assessment system and makes numerous recommendations, including that the three-tier assessment system be adopted on a pilot basis for further evaluation.

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216

Clearing A Road to Being Driving Fit by Better Assessing Driving Wellness – Development of California’s Prospective Three-Tier Driving-Centered Assessment System (Technical Report)

By: David F. Hennessy, Ph.D. & Mary K. Janke, Ph.D.

This report has two main purposes: (1) describe the development of California’s prospective 3-Tier driving-centered assessment system, and (2) present an “ecological perspective” on driver licensing. Driving-centered is an ecological concept—it means taking into consideration when, where, why, and how individual drivers customarily drive. Rather than an endpoint in delicensing drivers assessed as unsafe, 3-Tier fundamentally alters the purpose of assessment to be a starting point, if feasible, for extending the safe driving years of functionally-limited licensed drivers. The 3-Tier system integrates new assessment tools into those currently used by the Department of Motor Vehicles. All renewal applicants required to pass the department’s knowledge test are assessed on Tier 1, and those who are found to have a driving-relevant visual, mental, or physical limitation(s) are further screened on Tier 2. Based on these assessments, drivers are classified as driving well, somewhat functionally limited or extremely functionally limited; the extremely functionally-limited drivers are required to pass a Tier 3 road test to be licensed. The results of a small scale pilot study upon which the 3-Tier system was developed showed that somewhat-limited drivers, perhaps because they were less aware of their limitations, were more likely to be crash involved than extremely-limited drivers, who were probably more aware of their limitation(s) and compensated accordingly. In contrast, extremely-limited drivers were more likely to fail an office-based road test. The report concludes with 22 recommendations for statewide implementation of 3-Tier, including recommendations that the department’s R&D branch evaluate the reliability and validity of the current area drive test, and if needed, develop a better one, that this test be available to extremely limited drivers as an option for their Tier 3 road test requirement, and that the department educate somewhat-limited drivers about compensating for their limitation(s).

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221

Evaluation of the Class C Driver License Written Knowledge Tests

By: Thomas W. Reiner and Robert A. Hagge

This report represents the results of an evaluation of English and Spanish language written knowledge tests that were administered to applicants for an original or renewal Class C driver license. The report presents test fail rates for multiple attempts, mean error scores, and internal consistency validity for each test form, as well as the pass rate, item‐choice selection rates, and item‐total correlation for each item on each English test form. Items that need to be reviewed for possible rewording or replacement are identified. The results are based on 11,307 completed test forms collected from all California Department of Motor Vehicle field offices on August 4, 2005, or for a few offices on a subsequent Thursday.

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225

Statewide Evaluation of Commercial Drivers License Written Knowledge Tests

By: Chyan V. Wu and Sukhvir S. Brar

This report presents the results of an evaluation of the written knowledge tests administered to applicants for a commercial driver license or endorsement. The report presents the fail rate, mean number of errors, and internal‐consistency reliability coefficient for each test form, as well as the pass rate, item‐choice selection rates, and item‐total correlation for each test question on each test form. Items that need to be reviewed for possible rewording or replacement are identified. Additional recommendations for improving the testing process are also provided. The results are based on 8,576 test sheets completed in all California Department of Motor Vehicle field offices from November 27, 2007 to December 31, 2007.

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226

Evaluation of the Spanish Class C Driver License Written Knowledge Tests

By: Sukhvir S. Brar

This report presents the results of an evaluation of the Spanish language written knowledge tests completed by applicants for an original or renewal Class C driver license. The report presents the test fail rate, mean number of errors, and internal‐consistency reliability for each test form, as well as the pass rate, item choice selection rates, and item‐total correlation for each question on each form. Items that need to be reviewed for possible rewording or replacement are identified. The results are based on 4,539 completed test forms collected from all California Department of Motor Vehicle field offices from July 9 through 13, 2007.

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229

California’s 3‐Tier Pilot Process Analysis Appendix

By: Bayliss J. Camp, Ph.D.

This report presents the descriptive and predictive analyses of: (i) the results of a survey (n = 130) conducted of California Department of Motor Vehicles (CA DMV) Field Office and Driver Safety Branch staff and managers participating in the 3‐Tier Pilot project; (ii) interviews (n = 49) conducted of CA DMV Field Office and Driver Safety Branch staff and managers participating in the 3‐Tier Pilot; (iii) the results of a survey (n = 5,777) conducted of customers participating in the 3‐Tier Pilot; and (iv) the robustness of the Pelli‐Robson contrast sensitivity chart by location and technician (n = 9,934). These analyses form the primary evidentiary basis for some of the findings and conclusions presented in the 3‐Tier Pilot Process Analysis Report.

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