According to social control theory, social relationships may be beneficial to health when partners monitor and attempt to improve one another's health behaviors (Rook & Pietromonaco, 1987; Tucker & Anders, 2001). This dissertation expanded upon current theoretical models of social control by proposing the Individual Differences in Social Control (IDISC) Model, which considers the characteristics of who is most likely to offer and receive health-related social control and the downstream impacts on a partner's health behaviors and health outcomes. Furthermore, this study examined social control primarily in the context of friends, who may be important to health early in the lifespan. Pairs of students signed up to take part in a University-supported weight loss challenge, and psychosocial surveys, along with physical assessments at the Campus Health Center, were completed at four waves spanning over six months.
In the context of a dyadic longitudinal study, relationship satisfaction and personality were both found to significantly predict the giving and receiving of health-related social control, according to self-reports, and to a lesser extent, partner-reports. Specifically, higher relationship satisfaction, conscientiousness, agreeableness, and extraversion tended to predict helpful social control attempts (e.g., more positive and direct social control attempts). Whereas social control demonstrated inconsistent associations with health behaviors (e.g., eating healthy, physical activity), both positive social control and health behavior reports were associated with having a lower subsequent BMI. Perceived obstacles to weight loss showed associations with personality traits, giving social control to a partner, health behavior engagement at baseline and last report, and perhaps most importantly, to higher BMI and body fat percentage both at baseline and last report.
All together, the present findings suggest that theoretical models of social control processes should be expanded to reflect individuals' differential likelihood of giving and receiving health-related social control from a partner, such as a friend, spouse, or relative, across the lifespan in order to more fully portray the processes involved.