Wise Social Psychological Interventions to Improve Outcomes of Behavioral Weight Control in Children With Obesity

We propose a 2-arm, parallel group, randomized controlled trial to test the efficacy of adding two innovative "wise" social psychological interventions-growth mindset and self-affirmation-to a 6-month usual care family-based, group behavioral intervention for weight control in children with obesity, to reduce body mass index trajectory over 12 months, compared to the usual care behavioral intervention alone.

A total of 200 10-15-year-old children with obesity (BMI ≥ 95th percentile) will participate. All children will participate with their parents in a usual care six-month, family-based, group, behavioral weight control program. In addition, families randomized to the wise intervention condition will receive two, innovative social psychological interventions-growth mindset and self-affirmation-strategically selected and timed to enhance the behavioral intervention.

There remains a great need for innovative approaches to increase and sustain weight loss among children with obesity. We propose that existing weight control interventions are limited in their success with many children in part because of the many psychological barriers and threats they face when attempting to manage their weight. One novel and potentially effective and efficient way to enhance the success of behavioral treatments may be to focus on changing the mindsets and preparedness of the participant.

Measures will be collected at baseline, 3 months, 6 months (end of the behavioral treatment), and 12 months (follow-up 6 months after the end of treatment) from children and parents. Body mass index (BMI) trajectory over the entire 12 months is the primary outcome measure. Secondary outcome measures and potential moderating and/or mediating variables include waist circumference and triceps skinfold thickness, parent weight outcomes, physical activity (accelerometery), energy intake (24-hour dietary recalls), screen time, and hypothesized mediators of the behavioral intervention and the two social psychological interventions. We propose highly rigorous and transparent RCT methods.

Primary Hypothesis: Compared to children randomized to receive the usual care family-based, group behavioral weight control program alone, children randomized to receive the usual care family-based, group behavioral weight control program plus the wise social psychological interventions will have a significantly attenuated BMI trajectory over 12 months.