“Smoking-based selection and influence in gender-segregated friendship networks.”
By Liesbeth Mercken, Tom Snijders, Christian Steglich, Erkki Vartiainen, and Hein de Vries, 2010.
Addiction 105, 1280-1289.

Aims: The main goal of this study was to examine differences between boy and girl friendship networks regarding smoking-based selection and influence processes using newly developed social network analysis that allow the current state of continuously changing friendship networks to act as a dynamic constraint for changes in smoking behavior, while simultaneously allowing the current state of smoking behavior to be a dynamic constraint for changes in friendship networks. Design: Longitudinal design with four measurements. Setting: Nine junior high schools in Finland. Participants: 1326 adolescents that participated in the control group of the ESFA (European Smoking prevention Framework Approach) study, including 605 boys and 558 girls. Measurements: Smoking behavior of adolescents, parents, siblings, and friendship ties. Findings: Smoking-based selection of friends was found in boy as well as girl networks. However, support for influence among friends was only found in girl networks. Furthermore, girls and boys were both influenced by parental smoking behavior. Conclusions: Prevention programs need to focus on the role of selection processes besides paying attention to influence processes. Our results suggest that while girls need to learn to cope with peer influences, both boys and girls may benefit from reinforcing non-smoking attitudes in order to increase the likelihood that they select non-smoking peers. Prevention programmes should furthermore be combined with smoking cessation interventions for parents.

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