Social support, knowledge, and self-efficacy as correlates of osteoporosis preventive behaviors among preadolescent females.

OBJECTIVE To develop and test a model based on Bandura's social cognitive theory to predict healthy lifestyle behaviors for the prevention of osteoporosis. METHODS Participants were 354 girls, ages 8-11 years, recruited from area Girl Scout troops. Baseline data from a randomized trial of behavioral interventions are presented. Measures of social support, knowledge, self-efficacy, dietary calcium intake, and weight-bearing physical activity (WBPA) were obtained via interviews and self-administered questionnaires. RESULTS A structural equation model was tested and fit the data well. Family social support, perceived self-efficacy for eating a calcium-rich diet, and knowledge of WBPA significantly predicted calcium intake. Friend and family support for exercise predicted WBPA. Self-efficacy partially mediated the relationship between family support and calcium intake, as confirmed by Holmbeck's post-hoc probing strategy (2002). CONCLUSIONS Suggestions are made for primary prevention interventions such as parent and peer involvement, health education, and problem-solving training.