title: Friends in the 'hood: Should peer-based health promotion programs target nonschool friendship networks?
abstract: OBJECTIVE
  To examine the characteristics of inner city African-American adolescents nonschool-based and school-based friendship networks and to explore the influence of these networks on health risk behavior.
  
  
  METHODS
  We assessed close friendships networks in a probability sample of inner city African-American youth living in a single neighborhood and describe the networks and health risk behavior of network members. The initial probability sample was obtained via telephone (Random Digit Dialing [RDD] sampling) and followed up with in-person interviews with telephone respondents (seeds). Subsequently, seeds' friends were recruited and completed an in-person interview.
  
  
  RESULTS
  A majority of friendship networks included some nonschool friends (57%) and 24% of networks were composed exclusively of nonschool friends. As expected, youth were more likely to spend time with school-based friends on weekdays. On weekends, youth were equally likely to spend time with both school and nonschool networks. Youth in the same friendship group tended to engage in similar behaviors. Health risk behaviors were high regardless of whether networks were nonschool based, mixed, or school based.
  
  
  CONCLUSIONS
  The high proportion of nonschool friendships suggests that out-of-school networks may be an important influence in this population. Youth spend time with their friends, regardless of network type, on weekends, and weekends are a high-risk period for health-damaging behaviors. Levels of experience with health risk behaviors suggest that both school and nonschool environments require intervention. Future social influence prevention efforts that are broad-based are likely to have maximal impact.
authors.affiliation: Department of Medicine, University of California, San Francisco, San Francisco, CA, USA. pdolcini@psg.ucsf.edu
authors.forename: M Margaret
authors.initials: MM
authors.lastname: Dolcini
authors.forename: Gary W
authors.initials: GW
authors.lastname: Harper
authors.forename: Susan E
authors.initials: SE
authors.lastname: Watson
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Catania
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Ellen
mesh_terms: D000293:Adolescent; D001741:Black or African American / Q000523:psychology*; D005260:Female; D033062:Friends; D006293:Health Promotion; D006801:Humans; D008297:Male; D010379:Peer Group; D012111:Residence Characteristics; D012309:Risk-Taking; D014505:Urban Population