Description
This study assesses the effects of child, class, and family factors on participation in a completed osteoporosis primary prevention intervention study with early adolescents and their families. A two-group randomized control trial study design was utilized to employ an intervention based on the Behavioral Ecological Model. Children and parents attended eight co-educational classroom training sessions providing instruction on skill building and behavioral contingency management towards target behaviors. Families were randomly assigned to either diet and exercise (experimental) or injury prevention (control) intervention groups. Primary outcome measures included change in calcium intake and change in physical activity—behaviors known to mediate building of bone mass. The present study utilizes de-identified data in a secondary data analysis to evaluate possible correlations between various child, family, and classroom factors and subject compliance, which was measured through class attendance and homework completion. Multiple linear regression analyses were conducted with each dependent variable, which represent biopsychosocial aspects of early adolescence and will highlight contingencies that affect adherence to the intervention. Class pubertal and gender distribution, along with class size, explained a significant amount of variability in attendance. The model best describing variance in implementation included class size, receiving monetary incentive to attend classes, and the number of family members in the home. Previous analyses of the intervention's outcomes have shown that homework completion and attendance predicted calcium change and total body bone mineral density, respectively. Thus, research in factors that affect compliance may be used to inform the design of future classroom-based adolescent health interventions to maximize such programs' effectiveness in shaping changes in health behavior.
