The Food, Activity, Screens, and Teens (FAST) Study; Design and protocol

The Food, Activity, Screens, and Teens (FAST) Study was a school-based prospective cohort study, aiming to identify mechanisms of peer influence on weight-related behaviors (WRBs) among early adolescents. In 2017-18, FAST investigators conducted focus group interviews and field observations of sixth grade students at four ethnoracially diverse urban middle schools, then administered pilot surveys in two of the schools. In Fall 2018, investigators recruited a cohort of sixth graders in the same four schools for a three-year panel study, with four waves per year. Each wave measured height and weight, demographic characteristics, WRBs (physical activity, screen time, and dietary patterns), classes and activities, and social networks among peers. Peer network measures included friendship, social sentiments (liking/disliking), online and face to face interaction, kinship, cohabiting, and shared WRBs. The pandemic school closure in March 2020 interrupted fieldwork after wave 6, and the next five waves employed online and mail surveys while schools operated remotely. In Spring 2022, after schools reopened, investigators followed a subset of students into high school to collect a twelfth wave of data.