“Congratulations, You Have Been Randomized Into the Control Group!(?)”: Issues to Consider When Recruiting Schools for Matched‐Pair Randomized Control Trials of Prevention Programs

Abstract

Recruitment of schools prior to matching and randomization in an MP-RCT may facilitate the recruitment of schools and thus enhance both the statistical power and the representativeness of study findings. Future research would benefit from the consideration of a broader range of variables (eg, readiness to implement a comprehensive prevention program) both in matching schools and in evaluating their representativeness to nonparticipating schools.

Effects of thePositive ActionProgram on Indicators of Positive Youth Development Among Urban Youth

“…Sixty-eight schools met eligibility criteria, of which 18 agreed to participate, and the seven best-matched pairs were selected for participation (Ji, DuBois, Flay, & Brechling, 2008; Schochet & Novak, 2003). The following variables from the 2003-2004 CPS data were used as matching variables: percentage of White, African American, Hispanic, and Asian students; percentage of students who met or exceeded standards on the state achievement tests; attendance rate; truancy rate; percentage of students who received a free or reduced-price lunch; percentage of students who enrolled or left school during the school year (mobility); number of students per grade; percentage of parents who were involved with school activities; and percentage of teachers employed by the school who met minimal teaching standards.…”

“…Allocation to condition was blinded until assigned by the PI. A series of t -tests revealed that the PA and control schools were not significantly different from each other on any of the matching variables at baseline or at several other points during the study (Lewis et al, 2012) and that these schools as a group did not significantly differ from the remainder of the 68 schools eligible for the study (Flay, 2012; Ji et al, 2008). …”

Effects of a Social-Emotional and Character Development Program on the Trajectory of Behaviors Associated with Social-Emotional and Character Development: Findings from Three Randomized Trials

“…The schools in Chicago were matched and randomized in a similar fashion to those in the Hawai'i Trial (Li et al 2011). As in Hawai'i there were no significant differences at baseline on any of the variables used for matching (Ji et al 2008;Li et al 2011).…”

Effects of a School-Based Social–Emotional and Character Development Program on Health Behaviors: A Matched-Pair, Cluster-Randomized Controlled Trial

“…We excluded schools from involvement in the trial if they: 1) were non-community schools (e.g., magnet schools), 2) already had PA or a similar intervention, 3) had an enrollment rate below 50 or above 140 students per grade, 4) had annual student mobility rates over 40%, 5) had more than 50% of students who passed the Illinois State Achievement Test, and 6) had fewer than 50% of students who received free or reduced-price lunch; these criteria ensured selection of youth who could be considered “high-risk” (Ji et al, 2008). Of the 68 schools meeting eligibility criteria, we successfully contacted 36 who were also able to attend information sessions; of these 36, 18 agreed to participate given the understanding that they would be randomly assigned to PA or a control condition (Ji et al, 2008). …”

“…From these 18 schools, we created 9 best-matched pairs (matched on demographic and performance variables such as ethnicity, attendance rate, truancy rate, percentage of students on free or reduced-price lunch, and achievement test scores) using a SAS computer program provided by MPR; within each pair, we randomly assigned schools to PA or control using a random-number generation function (Ji et al, 2008). Given the nature of the intervention, blinding of condition status (e.g., by schools, students, teachers) was not possible.…”