The role of motivation in family-based guided self-help treatment for pediatric obesity.

BACKGROUND Identifying factors associated with effective treatment for childhood obesity is important to improving weight loss outcomes. The current study investigated whether child or parent motivation throughout the course of treatment predicted reductions in BMI. METHODS Fifty 8- to 12-year-old children with overweight and obesity (BMI percentiles 85-98%) and their parents participated in a guided self-help weight loss program, which included 12 brief sessions across 5 months. Parents and interventionists reported on child and parent motivation level at each session. Multilevel slopes-as-outcome models were used to examine growth trajectories for both child and parent BMI across sessions. RESULTS Greater interventionist-rated child motivation predicted greater reductions in child BMI; parent motivation did not. However, interventionist-rated parent motivation predicted greater reductions in parent BMI, and its impact on BMI became more pronounced over the course of treatment, such that sustained motivation was more important than initial motivation. Children who were older, Latino, or who had lower initial BMIs had slower reductions in BMI. CONCLUSIONS This study suggests that motivation may be an important predictor of reduced BMI in child obesity treatment, with sustained motivation being more important than initial motivation. In particular, interventionist-rated, but not parent-rated, motivation is a robust predictor of child and parent BMI outcomes. Future research may evaluate whether motivational interventions can enhance outcome, with particular attention to improving outcomes for Latino children.