The Weigh Forward, Financial Incentives for Maintenance of Weight Loss

The study will evaluate the effectiveness of financial incentives in improving maintenance of
weight loss. The investigators propose a 2-arm randomized controlled trial in which 258
participants who lose at least 5 kgs in a weight loss program will be randomized to one of
the following: 1) daily weigh-ins and weekly feedback, 2) daily weigh-ins,weekly feedback,
and a weekly escalating lottery-based financial incentive.

Study participants will be obese volunteers recruited from a major community-based weight
loss program (Weight Watchers), who have lost at least 5kg during the 4-6 months prior to
enrolling in the study. Upon enrollment, these participants will have an active online
membership with Weight Watchers. Among these participants, the following will be assessed: 1.
Assess the effectiveness of escalating lottery rewards, relative to the control group, on
maintenance of weight loss over the ensuing 6 months (Phase I); 2.The degree to which weight
loss is maintained in the intervention group relative to usual care during the 6 months
following the cessation of the interventions (Phase II).

During Phase I, incentives will be provided to some study participants (escalating lottery
arm) for the first 6 months and participants will be followed for 6 more months to examine
effects following cessation of incentives.

Inclusion Criteria:

- Adults age 30-80

- BMI between 30 and 45 prior to starting Weight Watchers

- Have a documented weight loss of at least 5kg in the past 4-6 months before enrolling

- Stable health

- Have an online Weight Watchers membership

Exclusion Criteria:

- Substance abuse

- Bulimia nervosa or related behaviors

- Pregnancy or breast feeding

- Medical contraindications to counseling about diet, physical activity, or weight
reduction

- Unstable mental illness

- Screen positive for pathological gambling on the basis of the 10 item DSM-IV criteria
(excluded if meets 5 or more criteria)

- Individuals unable to read consent forms or fill out surveys in English