Exploring the Optimal Duration of a Group-based Online Behavioral Weight Loss Program

This online pilot weight loss study will explore the feasibility of recruiting individuals to an established online behavioral weight loss program of varying duration (4 months vs. 6 months), We will compare 6-month weight losses between the two programs of shorter and longer duration, respectively, and obtain data to characterize weight maintenance experiences and retention. Both groups will receive the same intervention; the only difference is the number of weeks the group will meet. Both groups will complete follow ups at 2, 4, 6, and 12 months (12 months after the study begins).

Obesity presents a vexing public health challenge. Effective behavioral weight control treatments are available, loss, and projections show these interventions could have a significant impact on overall population health if the interventions were more broadly available. Internet delivery of behavioral lifestyle interventions has potential for broad reach and is thus an attractive option, although average weight losses tend to be lower than in a comparable behavioral program delivered in-person. Nonetheless, internet-delivered group behavioral weight control programs which incorporate synchronous chat "group sessions" can produce an average of 5% weight loss, with almost a quarter of participants losing at least 10% of their body weight at 6-months, and thus offer weight losses which are clinically significant. Online programs are more cost effective than in-person delivery of the same program, but efforts to optimize the delivery of online programs to achieve the best weight outcomes balanced against delivery cost are in their infancy. The current feasibility study seeks to explore critical elements to allow testing of whether a moderate dose program (16 online weekly video chat sessions) can produce weight losses comparable to the higher dose (24 weekly video chat sessions) internet-delivered behavioral weight loss program which is the established standard which we have demonstrated effective in the past. This pilot study will provide proof-of-concept to determine whether the approach is promising and if it is feasible to conduct. The pilot will explore the feasibility of recruiting individuals to weight loss programs of varying duration (4 months vs. 6 months), refine our ability to deliver the 16-session program, compare 6-month weight losses between the two programs of shorter and longer duration, respectively, and obtain data to characterize weight maintenance experiences and retention over the 12-month study period. Up to 80 individuals will be randomized into an online behavioral weight loss program lasting 4 months or 6 months. Individuals will meet weekly for one hour in a synchronous chat session with an experienced behavioral weight control counselor. Participants will be followed over 12 months from study start.