The gPROSPER sample includes 2,032 youth participating in the larger PROSPER project who provided buccal cell samples for genotyping. Of the 2,032 youth who provided buccal cell samples, 537 did so during the Wave 5 in-home assessment, and the remaining 1,495 provided samples through the mail as part of a young-adult follow-up assessment. Of the 2,032 participants who provided DNA,1,418 (69.78%) had valid peer nomination and self-report data. This reduced sample size was due to both missing data from the 9th-grade assessment (n=377), and the combined effect of genotype failures across all 5 SNPs (n= 237). The analytic sample was predominantly self-identified as Caucasian (90.6%), with fewer self-identified as Hispanics/Latino (4.4%), African-American (1.6%), Asian (1.3%), and other ethnicities (2%). About 23% of participants in the analysis sample took part in the family-focused program. Supplemental analyses were completed to confirm that the results of primary analyses do not vary based on family program participation.
