One of the innovations of the Add Health design was its ability to obtain independent and direct measures of the social environment of young people. The in-school and Waves I and II in-home interviews contain unique data that characterize the family, school, peer, relationship dyad, neighborhood, community and state contexts in which Add Health respondents lived. School context data come from the in-school surveys based on the census of students in each school, as well as from school administrator questionnaires. Peer network data were obtained in the in-school questionnaire. Adolescents nominated their five best male and five best female friends from the school roster (using a unique ID). Because nominated school friends also took the in-school interview, characteristics of respondents’ peer networks can be constructed by linking friends’ data from the in-school questionnaire and constructing variables based on friends’ actual responses. In the in-home Wave I and Wave II interviews, respondents nominated their best friend, as well as their romantic and sexual partners. If their friend or partner was also a member of the in-home sample, their data could be
