A Sociometric Approach to Understanding Concordance in Substance Use Perceptions Among Youth Experiencing Homelessness

Objective: Most studies examining peer influence on drug-use among youth experiencing homelessness (YEH) have relied on perceptions of peer use rather than measuring peers’ self-reported use, an approach that can inflate estimates of peer substance use behavior. Sociometric network data provide an optimal mechanism to compare perceptual data to actual self-reports from peers. Method: Using an event-based approach, we recruited a sample of YEH (N = 241), ages 13–25 years, between October 2011 and February 2012 from 2 drop-in centers—1 in Hollywood, CA, and 1 in Santa Monica, CA. We used multilevel multiple membership modeling to investigate participant-level, network-level, and relationship-level factors associated with the accuracy of respondent perceptions. Results: The accuracy of respondent perceptions of peer substance use was high (70%–90% depending on the substance). The individual- and network-level factors associated with accuracy or inaccuracy varied by substance. Conclusions: Interventions designed to reduce the risk of substance use among YEH may benefit from using a social norms approach that emphasizes changing norms at a community/group level rather than at an individual level.