Keep it Off

Compare the efficacy of a lottery-based incentive, traditional direct payment incentive, and control of daily feedback without any incentive for weight-loss maintenance.

Pamela A. Shaw, PhD
William S. Yancy, Jr., MD

Background and Aim

Obesity continues to be a serious public health challenge. Rates are increasing worldwide, with nearly 70% of the US adults overweight or obese, leading to increased clinical and economic burden. While successful approaches for achieving weight loss have been identified, techniques for long-term maintenance of initial weight loss have largely been unsuccessful. Financial incentive interventions have been shown in several settings to be successful in motivating participants to adopt healthy behaviors.

Keep It Off is a three-arm randomized controlled trial that compares the efficacy of a lottery-based incentive, traditional direct payment incentive, and control of daily feedback without any incentive for weight-loss maintenance. This design allows comparison of a traditional direct payment incentive with one based on behavioral economic principles that consider the underlying psychology of decision-making.

Intervention and Design

Keep It Off is a pragmatic trial that recruited, consented, enrolled, and followed patients electronically. Participants were provided a wireless weight scale that electronically transmitted daily self-monitored weights. Weights were verified every 3 months at a Weight Watchers center local to the participant and electronically transmitted.

Intervention - Participants were randomized in a 2:1 ratio for each active arm relative to control, with a targeted 188 participants in total. Eligible participants were those aged 30–80 who lost at least 11 lb (5 kg) during the first 4 months of participation in Weight Watchers, a national weight-loss program, with whom we partnered. The interventions lasted 6 months (Phase I); participants were followed for an additional 6 months without intervention (Phase II).

Main Outcomes and Measures - The primary objectives of this study are the three possible arm comparisons of weight-loss maintenance at the end of Phase I (month 6). As a secondary objective, we assess the degree to which weight loss was maintained in the intervention groups relative to control during the 6 months following cessation of the interventions (Phase II).

Way to Health Use

  • Study Enrollment: Enroll and randomize participants in the study

  • Survey Administration: Administer and collect survey responses

  • Device Integration: Collect weight data from Withings scale

  • Financial Incentives: Provide participants with financial incentives for adherence

Findings and Conclusions

Using the study web-based platform, they integrated recruitment, enrollment, and follow-up procedures into a digital platform that required little staff effort to implement and manage. They randomized 191 participants in less than 1 year.

This study demonstrated that their pragmatic design was successful in rapid accrual of participants in a trial of interventions to maintain weight loss. Keep It Off was implemented and conducted with minimal staff effort. This study has the potential to identify a practical and effective weight-loss maintenance strategy.


The Design and Conduct of Keep It Off: An Online Randomized Trial of Financial Incentives for Weight-Loss Maintenance