Availability of driver's license master lists for use in government-sponsored public health research.

Although the percentage of US drivers with valid driver's licenses varies from state to state, it has historically been high enough to constitute a useful sampling frame for many public health purposes. Over the past decade, states have had to restrict access to this information to comply with the Driver's Privacy Protection Act (18 U.S.C. 2721-2725). In 2009 and 2010, the authors conducted a survey of all 50 states on the availability of master lists of licensed drivers to be used to contact citizens of each state for research purposes. A hypothetical situation requiring driver's license data was sent to each state's responsible government agency for review. In addition, the authors collected data on opt-out mechanisms available to drivers, costs to researchers, and additional state privacy policies pertaining to driver's license files. A total of 42 states (84%) responded; 16 (32%) states allowed access to data, 4 (8%) states were unable to respond to the hypothetical situation, and 22 (44%) states denied access to data. A total of 74,697,574 records were available from the 16 states providing driver's license data. Although the Driver's Privacy Protection Act has restricted access to data on licensed drivers, these data are still an available resource in many states.