Background: To facilitate identification of effective interventions to prevent alcohol-impaired driving, we created a register of relevant research studies and systematic reviews by searching 11 bibliographic databases, contacting 97 government agencies, and handsearching conference proceedings. Objective: To test the register s utility in relation to existing systematic reviews. Methods: We selected three published reviews evaluating school-based programs, designated driver programs, and mass media campaigns, respectively. Together they cited 22 studies with designs eligible for the register (i.e., randomized, quasi-randomized, controlled before-after and interrupted time series studies). To evaluate the register s comprehensiveness (proportion of review citations found in the register), we searched it for exact citations or related/follow-up studies. To assess the register s added value (studies eligible for but not cited in the published reviews), we screened the remaining 764 citations and the reference lists of systematic reviews included in the register, examining full-text reports to confirm eligibility based on the reviews inclusion criteria. Finally, we screened the register for studies completed since the reviews were conducted, to assess its utility for updates. Results: The register included 16/22 (73%) review citations: 100% for designated-driver programs, 73% for school-based programs, and 60% for mass media campaigns. It included 15/18 (83%) journal articles but only 1/4 (25%) government/technical reports. The register yielded three additional eligible studies of school-based programs, increasing the total relevant studies identified by 14%. We also identified four new studies usable for updates of two of the reviews. Conclusion: A register created through database and hand searches can enhance systematic reviews of interventions to prevent alcohol-impaired driving by increasing identification of available evidence and assisting updates. However, additional effort is needed to identify government reports and other gray literature. The register is regularly updated and incorporated into the Cochrane Injury Group s specialized register, making it accessible to researchers and policy-makers.