Adding Financial Incentives to Online Group-Based Behavioral Weight Control: An RCT.

ABSTRACT

INTRODUCTION: Internet-delivered behavioral weight control is promising for expanding the reach and availability of weight management, but online programs produce lower weight losses than typically achieved in person. Financial incentives have been shown to increase weight losses. This study examined whether adding financial incentives for self-monitoring and achieving target weight losses increases weight losses attained in a fully online, group-based behavioral weight management program compared with the same program alone. STUDY DESIGN: This study was an RCT. SETTING/PARTICIPANTS: Adults with overweight and obesity (n=418; 91% female; 28% minority) were recruited from 2 clinical centers. INTERVENTION The intervention was a 24-session online group-based behavioral weight control program with weekly synchronous chat sessions (Internet-only) or the same program with weekly financial incentives for self-monitoring body weight and dietary intake daily and for achieving target weight losses at 2 and 6 months (Internet + incentives). MAIN OUTCOME MEASURES: This study measured weight loss at 6 months and treatment engagement (attendance, self-monitoring of body weight, dietary intake, and physical activity). Data were collected between February 2016 and August 2018, and analyses were completed in 2019. RESULTS: Participants randomized to the Internet + incentives group lost more weight (-6.4 [SD=5.5] kg) than those in the Internet-only group (-4.7 [SD=6.6] kg; p<0.01). Further, a higher proportion of the Internet + incentives group achieved ≥5% weight loss (55%) than those in the Internet-only group (40%; p<0.05). Treatment engagement was higher in the Internet + incentives condition, with greater self-monitoring of behaviors targeted by incentives, as well as higher rates of behaviors not targeted and higher self-reported physical activity. Study retention was higher among those in the Internet + incentives condition (91%) than those in the Internet-only condition (81%; p=0.003). CONCLUSIONS: Adding financial incentives to a program delivered fully online increases weight losses compared with the program alone and can achieve weight losses comparable to in-person programs, offering potential for substantial geographic reach. TRIAL REGISTRATION This study is registered at www.clinicaltrials.gov NCT02688621.