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

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

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

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.

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