Primary Outcomes (explanation)
Voter turnout for Perry study participants: Gathered from public records, using data supplied by the firm Voter Contact Services, based on each participant’s name, address, and birthday
Voter turnout for STAR study participants: Polimetrix, an independent polling firm, matched the names and birth dates of the Project STAR subjects to their national list of registered voters. The information, however, was sometimes insufficient to generate a unique match. To differentiate among multiple matches, the search process also considered the locations to which subjects were likely to move. For example, individuals born in Tennessee have a higher probability of moving to Kentucky or Missouri than to Connecticut or North Dakota. Using this information, and blind to the treatment or control status of the subjects, Polimetrix searched for each subject in their national voter database and compiled a list of likely matches. A hit was determined by name, date of birth, and state of residence, in that order, and assigned a score indicating the likelihood of a correct match.
Voter turnout for IHAD participants: Since this was not a study but a scholarship program, a control group was created out of students who attended fifth grade during the year preceding and following the IHAD cohort. Only students who were eligible for the free or reduced lunch program were eligible for IHAD, thus the control group also was also made from this group. Boulder Valley School District provided the IHAD Foundation with a list of students that met these criteria. These students were contacted through a phone survey and their participation in the free or reduced lunch program and the IHAD program were checked. Voter turnout information for all those who were part of the free or reduced lunch program was checked from registration rolls.