Leveraging social influence to address overweight and obesity using agent-based models: The role of adolescent social networks

Authored by J Zhang, L Tong, P J Lamberson, R A Durazo-Arvizu, A Luke, D A Shoham

Date Published: 2015

DOI: 10.1016/j.socscimed.2014.05.049

Sponsors: United States National Institutes of Health (NIH)

Platforms: NetLogo

Model Documentation: Other Narrative

Model Code URLs: http://www.sciencedirect.com.ezproxy1.lib.asu.edu/science/MiamiMultiMediaURL/1-s2.0-S0277953614003438/1-s2.0-S0277953614003438-mmc1.docx/271821/html/S0277953614003438/a7252302de2eb636f1a1340eeff3c052/mmc1.docx

Abstract

The prevalence of adolescent overweight and obesity (hereafter, simply ``overweight{''}) in the US has increased over the past several decades. Individually-targeted prevention and treatment strategies targeting individuals have been disappointing, leading some to propose leveraging social networks to improve interventions. We hypothesized that social network dynamics (social marginalization; homophily on body mass index, BMI) and the strength of peer influence would increase or decrease the proportion of network member (agents) becoming overweight over a simulated year, and that peer influence would operate differently in social networks with greater overweight. We built an agent-based model (ABM) using results from R-SIENA. ABMs allow for the exploration of potential interventions using simulated agents. Initial model specifications were drawn from Wave 1 of the National Longitudinal Study of Adolescent Health (Add Health). We focused on a single saturation school with complete network and BMI data over two waves (n = 624). The model was validated against empirical observations at Wave 2. We focused on overall overweight prevalence after a simulated year. Five experiments were conducted: (1) changing attractiveness of high-BMI agents; (2) changing homophily on BMI; (3) changing the strength of peer influence; (4) shifting the overall BMI distribution; and (5) targeting dietary interventions to highly connected individuals. Increasing peer influence showed a dramatic decrease in the prevalence of overweight; making peer influence negative (i.e., doing the opposite of friends) increased overweight. However, the effect of peer influence varied based on the underlying distribution of BMI; when BMI was increased overall, stronger peer influence increased proportion of overweight. Other interventions, including targeted dieting, had little impact. Peer influence may be a viable target in overweight interventions, but the distribution of body size in the population needs to be taken into account. In low-obesity populations, strengthening peer influence may be a useful strategy. (C) 2014 Elsevier Ltd. All rights reserved.

Tags

Dynamics diffusion Contagion Prevalence Public-health Interventions Body-mass index Physical-activity Us children Weight