Real-world effectiveness of the Bright Bodies healthy lifestyle intervention for childhood obesity.

Objective: This study aimed to examine the extent to which Bright Bodies, a high-intensity, family-based pediatric weight management intervention, improved BMI for participants since publication of the randomized controlled trial establishing efficacy in 2007 and to describe adaptations to the program.

Methods: For participants enrolled from 2008 to 2018, linear mixed-effects models were used to estimate monthly change in BMI expressed as percentage of the 95th percentile (%BMIp95) during participants' first beginner-level program.

Results: The sample included 396 youth individuals (mean age: 11.7  [SD 2.8] years, 61.6% female, 37.1% non-Hispanic Black, 26.3% Hispanic or Latino, 53.8% with public insurance, 80.1% with severe obesity). Across the 11 years, participants' %BMIp95 reduced on average by 1.63% (95% CI: 1.44%-1.82%) per month during their first program (mean duration: 10 weeks) after adjusting for age, sex, season and year, starting %BMIp95, race and ethnicity, and insurance category. Greater reduction in %BMIp95 was associated with male versus female sex, spring/fall versus winter seasons, enrollment in 2008 to 2018 versus 2015 to 2018, and higher starting %BMIp95 (p value for all <0.001). Adaptations since 2007 included pragmatic changes to increase engagement and address funding shortages.

Conclusions: These results suggest sustained clinical effectiveness of Bright Bodies in the context of real-world adaptations.