Tracking Adolescents With Global Positioning System-Enabled Cell Phones to Study Contextual Exposures and XXXX and Marijuana Use: A Pilot Study.

@entity285 @entity262 @entity146
PURPOSE: Measuring activity spaces, places adolescents spend time, provides information about relations between contextual exposures and @entity146 . We studied whether contextual exposures in adolescents' activity spaces differ from contextual risks present in residential contexts and examined relationships between contextual exposures in activity spaces and @entity285 /marijuana use. METHODS: Adolescents (N  = 18) aged 16-17 years carried @entity262 ( @entity262 )-enabled smartphones for 1 week, with locations tracked. Activity spaces were created by connecting @entity262 points sequentially and adding buffers. Contextual exposure data (e.g., @entity285 outlets) were connected to routes. Adolescents completed texts regarding behaviors. RESULTS: Adolescent activity spaces intersected 24.3 census tracts and contained nine times more @entity285 outlets than that of residential census tracts. Outlet exposure in activity spaces was related to drinking. Low-socioeconomic status exposure was related to marijuana use. CONCLUSIONS: Findings suggest substantial differences between activity spaces and residential contexts and suggest that activity spaces are relevant for adolescent @entity146 .
