title: Network interventions on physical activity in an afterschool program: an agent-based social network study.
abstract: OBJECTIVE
  We studied simulated interventions that leveraged social networks to increase physical activity in children.
  
  
  METHODS
  We studied a real-world social network of 81 children (average age = 7.96 years) who lived in low socioeconomic status neighborhoods, and attended public schools and 1 of 2 structured afterschool programs. The sample was ethnically diverse, and 44% were overweight or obese. We used social network analysis and agent-based modeling simulations to test whether implementing a network intervention would increase children's physical activity. We tested 3 intervention strategies.
  
  
  RESULTS
  The intervention that targeted opinion leaders was effective in increasing the average level of physical activity across the entire network. However, the intervention that targeted the most sedentary children was the best at increasing their physical activity levels.
  
  
  CONCLUSIONS
  Which network intervention to implement depends on whether the goal is to shift the entire distribution of physical activity or to influence those most adversely affected by low physical activity. Agent-based modeling could be an important complement to traditional project planning tools, analogous to sample size and power analyses, to help researchers design more effective interventions for increasing children's physical activity.
authors.affiliation: Jun Zhang and David A. Shoham are with the Department of Public Health Sciences, Stritch School of Medicine, Loyola University, Chicago, IL. Eric Tesdahl is with the Department of Human and Organizational Development, Vanderbilt University, Nashville, TN. Sabina B. Gesell is with the Department of Social Sciences and Health Policy, and The Maya Angelou Center for Health Equity, Wake Forest School of Medicine, Winston-Salem, NC.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: David A
authors.initials: DA
authors.lastname: Shoham
authors.forename: Eric
authors.initials: E
authors.lastname: Tesdahl
authors.forename: Sabina B
authors.initials: SB
authors.lastname: Gesell
mesh_terms: D001837:Body Weights and Measures; D002648:Child; D015444:Exercise; D005260:Female; D006293:Health Promotion / Q000458:organization & administration*; D006801:Humans; D008297:Male; D009937:Organizational Objectives; D050177:Overweight / Q000453:epidemiology; D011204:Poverty Areas; D015397:Program Evaluation; D011634:Public Health; D012574:Schools / Q000458:organization & administration*; D057185:Sedentary Behavior; D012944:Social Support; D012959:Socioeconomic Factors