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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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. Among these participants, the following will be assessed: 1. The effectiveness of a daily lottery-based financial incentive, relative to the control group, on weight loss and weight maintenance; 2. The effectiveness of a direct payment incentive, relative to the control group, on maintenance of weight loss; 3. Assess the comparative effectiveness of lottery-based and direct payment financial incentives on weight loss and maintenance; 4. The degree to which weight loss is maintained in the intervention groups relative to usual care during the 6 months following cessation of the intervention will also be determined. During Phase I, incentives will be provided to some study participants (direct payment and lottery arm) for the first 6 months and subjects 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: Financial incentive


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 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control Arm<br>No other financial incentive other than for the 3-, 6-, 9-, & 12-month weigh-ins and surveys. Participants will receive daily feedback for months 1-6 and will be observed without intervention in Phase II (months 7-12). Two weigh-ins will be required during Phase II, one at 9 months and the other at 12 months. | |
| Experimental: Direct payment<br>In addition to the incentives for the 3-, 6-, 9-, & 12-month weigh-ins, participants who meet their daily goal will be eligible to receive an incentive for each day their goal is met during the first 6 months of the study. All daily incentive earnings will be paid out after verifying participants' weights during an in person weigh in at a Weight Watchers location at months 3 and 6. Winnings will be proportional to weight loss. For example, if a participant's goal was to lose 6 pounds by month 3, but he/she only lost 3 pounds, that participant would only receive 50% of their total eligible winnings. Similar to the control arm, participants will receive daily feedback for months 1-6 and will be observed without intervention in Phase II (months 7-12). The weigh-ins at 9- and 12-months will also be required. | Behavioral: Financial incentive<br>* Participants in the direct payment and lottery arms will receive financial incentives as part of the intervention. See arm descriptions for more detail.<br>|
| Experimental: Lottery<br>In addition to the incentives for the 3-, 6-, 9-, & 12-month weigh-ins, participants who meet their daily goal will be eligible for the daily lottery during the first 6 months of the study. The expected daily winning for the lottery is the same as for the direct payment arm. All daily incentive earnings will be paid out after verifying participants' weights during an in person weigh in at a Weight Watchers location at months 3 and 6. Winnings will be proportional to weight loss. For example, if a participant's goal was to lose 6 pounds by month 3, but he/she only lost 3 pounds, that participant would only receive 50% of their total eligible winnings. Similar to the control arm, participants will receive daily feedback for months 1-6 and will be observed without intervention in Phase II (months 7-12). The weigh-ins at 9- and 12-months will also be required. | Behavioral: Financial incentive<br>* Participants in the direct payment and 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 From Baseline to 6 Months |  | 6 months | 
| Change in Weight From Baseline to 12 Months |  | 12 months |