The Impact of Group Commitment Contracts on Smoking Cessation and Weight Loss

National Bureau of Economic Research, Inc.

Status: Suspended

Conditions: Weight Loss; Smoking Cessation

Treatments: Behavioral: Group Commitment Contract; Other: Information; Behavioral: Individual Commitment Contract; Behavioral: Individual Monetary Rewards

Study type: Interventional

Funder types: Other

Identifiers

NCT04224727

0009

Details and patient eligibility

About

We will conduct a randomized controlled trial to evaluate the effectiveness of group commitment contracts for smoking cessation and weight loss.

Full description

Initial screening will be conducted online via the Qualtrics survey platform. Respondents meeting the inclusion/exclusion criteria will immediately be randomized into one of the intervention arms described below, and then take a baseline survey. This baseline survey will also be conducted online via the Qualtrics survey platform. The initial screening, randomization, and baseline survey should take approximately 15 minutes total and can be completed anywhere the participant has an internet connection.

INTERVENTION: Respondents who meet the inclusion/exclusion criteria will be randomized into one of the following arms:

1. Control Arm (No Intervention)
2. Group Contract Arm
3. Individual Monetary Rewards Arm
4. Individual Commitment Contract Arm

Subjects in Arms #2-4 will be cross-randomized into two subgroups:

A. Additional information treatments on the likelihood of success of the different incentives and contracts, with the goal of shifting "naives" to "sophisticates."

B. No additional information treatments.

FOLLOW-UP SURVEY: After the participants finish their contract, they will be emailed a link to the follow-up survey that will be administered online via the Qualtrics survey platform. The survey should take approximately 5 minutes and can be completed anywhere the participant has an internet connection. Participants will be directly prompted to answer whether they have been able to quit smoking or lose their target weight in the past six months. If a participant self-reports a claim of smoking cessation or successful weight loss, they will be asked to furnish at-home verification of their claim.

IN-PERSON VERIFICATION: A randomly selected subset of successful participants will be asked for in-person verification of their claim with a urine test (smoking cessation) or in-person weigh-in (weight loss) at a Quest Diagnostics location of their choice.

Enrollment: 3,600 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Aged 18 years or older
• Has smartphone with capability to reach internet daily and download app
• Able and willing to visit Quest location or take an at-home verification test
• Willing to furnish a payment method for commitment contract stakes

If completing a smoking cessation contract:

• Daily smoker

If completing a weight loss contract:

• Has access to a functioning scale
• Interest in losing weight at a pace of 2 lb or fewer per week, with a target BMI at or above 18.5

Exclusion criteria

• Pregnancy
• Any terminal illness

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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3,600 participants in 7 patient groups

Control

No Intervention group

Description:

Subjects are not offered a group commitment contract, individual commitment contract, or individual monetary rewards. Subjects do not receive additional information treatments.

Group Commitment Contract + Information

Experimental group

Description:

Subjects are offered a group commitment contract for smoking cessation or weight loss and receive additional information treatments.

Treatment:

Other: Information

Behavioral: Group Commitment Contract

Individual Monetary Rewards + Information

Experimental group

Description:

Subjects are offered individual monetary rewards for smoking cessation or weight loss and receive additional information treatments.

Treatment:

Other: Information

Behavioral: Individual Monetary Rewards

Individual Commitment Contract + Information

Experimental group

Description:

Subjects are offered an individual commitment contract for smoking cessation or weight loss and receive additional information treatments.

Treatment:

Behavioral: Individual Commitment Contract

Other: Information

Group Commitment Contract

Experimental group

Description:

Subjects are offered a group commitment contract for smoking cessation or weight loss and receive no additional information treatments.

Treatment:

Behavioral: Group Commitment Contract

Individual Monetary Rewards

Experimental group

Description:

Subjects are offered individual monetary rewards for smoking cessation or weight loss and receive no additional information treatments.

Treatment:

Behavioral: Individual Monetary Rewards

Individual Commitment Contract

Experimental group

Description:

Subjects are offered an individual commitment contract for smoking cessation or weight loss and receive no additional information treatments.

Treatment:

Behavioral: Individual Commitment Contract