The Weigh Forward, Financial Incentives for Maintenance of Weight Loss

Study Overview
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Brief Summary
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This study aims to evaluate the effectiveness of financial incentives in improving and maintaining weight loss.

Detailed Description
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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.

Official Title
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A Randomized Trial of Financial Incentives for Maintenance of Weight Loss

Conditions
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Obesity

Intervention / Treatment
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* Behavioral: Escalating Lottery


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Participants will receive weekly tips and weekly feedback for months 1-6 and will be observed without intervention in Phase II (months 7-12). The weekly feedback will pertain to whether or not the participant met his/her goal of weighing at least 6/7 days. The weekly tips will give information and suggestions on how to make it easier to weigh-in most days of the week. No financial incentive other than for the midpoint and end of study surveys will be given. | |
| Experimental: Escalating lottery<br>Participants will receive weekly tips and weekly feedback for months 1-6 and will be observed without intervention in Phase II (months 7-12). The weekly feedback will pertain to whether or not the participant met his/her goal of weighing at least 6/7 days. The weekly tips will give information and suggestions on how to make it easier to weigh-in most days of the week. In addition to the incentives for midpoint and end of study surveys, participants who meet their weekly goal (weighing in 6 of 7 days) will be eligible for the weekly lottery during the first 6 months of the study. The expected weekly winning for the lottery is $3.55 in week 1 and this expected value will increase by $0.43 per week for each week the participant achieves their goal of weighing 6/7 days. All incentive earnings will be paid out on a monthly basis. | Behavioral: Escalating Lottery<br>* Participants in the lottery arms will receive financial incentives as part of the intervention. See arm descriptions for more detail.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Weight, Baseline and 6 Months | Among participants who lost 5 kg or more of baseline weight prior to randomization, assess the effectiveness of escalating lottery rewards, relative to the control group, on maintenance of weight loss after 6 months of intervention | 6 months | 
| Change in Weight, 6 Months and 12 Months | Among participants who lost 5 kg or more of baseline weight prior to randomization, assess the degree to which weight loss is maintained in the intervention groups relative to usual care during the 6 months following the cessation of the interventions | 12 months |