A Randomized Incentive-Based Weight Loss Trial in Singapore

Duke University

Status: Completed

Conditions: Incentives; Obesity

Treatments: Other: Financial Incentives

Study type: Interventional

Funder types: Other

Identifiers

NCT01533454

0742_001

Details and patient eligibility

About

The purpose of this study is to test the extent to which incentives, when combined with an existing evidence-based weight loss program, improve weight loss and weight loss maintenance. It will also compare the cost-effectiveness of the incentive-based weight loss programs to the basic program without incentives.

Full description

Globally, the rise in obesity rates has reached epidemic proportions, and in Singapore 53% of adults have a body mass index (BMI) great than 23.0 kg/m2, a level that increases risk for chronic disease among Asians. This study aims to test the extent to which traditional or behavioural economic incentives, when combined with an existing evidence-based weight loss program, improve weight loss and weight loss maintenance. Data will be collected through a two-arm (basic weight loss program, basic program plus traditional or behavioural economic incentives) randomized controlled trial (RCT) where key outcome variables are defined as weight loss (kilograms) at 8 months when the incentive program concludes, and at 12 months, after a 4 month period in which no additional incentives are provided. We hypothesize that at both 8 and 12 months, weight loss will be greater in the incentive arm than in the arm without incentives. The growing obesity epidemic, the high costs of obesity to employers, insurers and governments across Asia, and the fact that the incentive program is designed to be close to cost neutral, suggest that this research has high potential to have a significant public health impact, both in Singapore and the region.

Enrollment: 161 patients

Sex: All

Ages: 21 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Signed informed consent
• Age 21+
• BMI 25+
• Willing to be randomized into 1 of the 2 study arms
• Willing to pay the $399 entry fee
• Stated willingness to commit to participating in all assessments regardless of weight change or study arm

Exclusion criteria

• Current pregnancy/lactation (women who become pregnant during the study will be withdrawn)
• Type 1 diabetes
• Type 2 diabetes on medication other than Metformin
• End-stage Renal Disease
• Ischemic Heart Disease requiring intervention in the past 6 months
• Thyroid disease that has yet to stabilize
• Changes in weight of greater than 3% in the past 6 months
• Use of weight loss medication in the past 6 months
• Malignancy requiring chemotherapy/radiation in the past 5 years
• Acute medical problems requiring 3+ days of missed work during previous 4 week period
• Any serious hospitalization or surgery in the past 6 months
• Use of corticosteroids in the past 6 months
• Answer 'YES' to any of the PAR-Q questions
• Unable to obtain MD consent from a physician giving permission to participate in the study
• Evidence of clinical depression (as assessed by the Beck Depression Inventory)
• Currently on medications for a mental health or substance abuse condition
• Evidence of binge eating based on the Binge Eating Disorders Scale (BEDS)
• Unable to communicate in English
• Additional concerns in which the clinical investigator deems problematic for participation

Trial design

Primary purpose: Health Services Research

Allocation: Randomized

Interventional model: Factorial Assignment

Masking: Single Blind

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161 participants in 2 patient groups

Control

No Intervention group

Description:

Control participants will attend a 4-month structured weight-loss program and attend subsequent follow-ups at 4-month intervals upon completion of the program.

Incentives

Experimental group

Description:

Incentive arm participants will be offered an additional program (in addition to the COMM program) where they can earn incentives for meeting specified weight loss targets or step goals. They will be offered a choice between traditional (payments with certainty) and behavioral(payments paid via lottery) incentives.

Treatment:

Other: Financial Incentives