The Healthy Weigh study of lottery-based incentives and environmental strategies for weight loss: Design and baseline characteristics

Abstract Identifying effective strategies for treating obesity is a clinical challenge and a public health priority. The present study is an innovative test of the relative effectiveness of lottery-based financial incentives and environmental strategies on weight loss and maintenance. The Healthy Weigh study is evaluating the comparative effectiveness of behavioral economic financial incentives and environmental strategies, separately and together, in achieving initial weight loss and maintenance of weight loss, in obese urban employee populations. Healthy Weigh is a multi-site, 4-arm randomized controlled trial (RCT) in which 344 employed participants were randomized to one of four arms. The study arms are: 1) standard employee wellness benefits and weigh-ins every 6 months (control arm/usual care); and the control/usual care plus either: 2) daily lottery incentives tied to achievement of weight loss goals (incentive arm); 3) individually tailored environmental strategies around food intake and physical activity (environmental arm); or 4) a combination of incentives and environmental strategies (combined arm). This trial used a web-based platform to enroll, communicate with, and track participant weight change. Wireless scales were used by participants in the three treatment group arms to digitally transmit daily/weekly weights. For females, the baseline median (interquartile range, IQR) for BMI and weight were 37.0 (33.5, 40.6) and 219.9 (198.1, 248.6), respectively; and for males, they were 36.0 (32.8, 39.8) and 247.9 (228.1, 279.5), respectively. The population was generally well-educated. This study demonstrated that multi-site employee-based recruitment for a weight-control intervention study is feasible but may need additional time for coordination between diverse environments.