Not provided
Not provided
Not provided
Not provided
Not provided
This study was suspended due to low take-up in the group commitment contracts arm (~6%), revealing inadequate statistical power to justify moving forward. There were no safety concerns.
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Class |
|---|---|
| Northwestern University | OTHER |
Not provided
Not provided
Not provided
Not provided
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:
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.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Control | No Intervention | 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 | Subjects are offered a group commitment contract for smoking cessation or weight loss and receive additional information treatments. |
|
| Individual Monetary Rewards + Information | Experimental | Subjects are offered individual monetary rewards for smoking cessation or weight loss and receive additional information treatments. |
|
| Individual Commitment Contract + Information | Experimental | Subjects are offered an individual commitment contract for smoking cessation or weight loss and receive additional information treatments. |
|
| Group Commitment Contract | Experimental | Subjects are offered a group commitment contract for smoking cessation or weight loss and receive no additional information treatments. |
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Group Commitment Contract | Behavioral | A group contract where the primary individual, who will be tracked by the study, can invite peers to join the contract and form their group. To initiate a contract, a user must choose: the stakes, start date, and (for weight loss contracts) target weight, and and, optionally, to allow other members to have the power to invite other people to join the group. |
| Measure | Description | Time Frame |
|---|---|---|
| Smoking Cessation / Weight Loss | Participants will be directly prompted to answer whether they have been able to quit smoking or reach their target weight in the past six months. If a participant self-reports a claim of success, they will be asked to furnish at-home (and, in some cases, in-person) verification. | 6 months |
Not provided
| Measure | Description | Time Frame |
|---|---|---|
| Smoking Cessation / Weight Loss by Sex/Gender, Race, and Ethnicity | Participants will be directly prompted to answer whether they have been able to quit smoking or reach their target weight in the past six months. If a participant self-reports a claim of success, they will be asked to furnish at-home (and, in some cases, in-person) verification. | 6 months |
Inclusion Criteria:
If completing a smoking cessation contract:
If completing a weight loss contract:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Dean Karlan, PhD | Northwestern University | Principal Investigator |
| Anna Tuchman, PhD | Northwestern University | Principal Investigator |
| Jonathan Zinman, PhD | Dartmouth College | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| Northwestern University, Global Poverty Research Lab | Evanston | Illinois | 60208 | United States |
Not provided
Not provided
Not provided
Not provided
Not provided
| ID | Term |
|---|---|
| D016540 | Smoking Cessation |
| D015431 | Weight Loss |
| ID | Term |
|---|---|
| D015438 | Health Behavior |
| D001519 | Behavior |
| D001836 | Body Weight Changes |
| D001835 | Body Weight |
Not provided
Not provided
Respondents who meet the inclusion/exclusion criteria will be randomized into one of the following arms:
To understand the effect that knowledge about the effectiveness of commitment contracts has on uptake, smoking quit rates, and weight loss, we will be cross-randomizing those assigned to Arms #2-4 into further subgroups:
Subgroup A. In the initial survey, participants will receive additional information treatments on the likelihood of success of the different incentives and contracts, with the goal of shifting "naives" to "sophisticates." In other words, we aim to provide information that will encourage present-biased or loss-averse individuals to participate in the programs that offer the greatest chance at success.
Subgroup B. Participants will not receive any information about commitment contracts.
Not provided
Not provided
Not provided
Not provided
|
| Individual Monetary Rewards | Experimental | Subjects are offered individual monetary rewards for smoking cessation or weight loss and receive no additional information treatments. |
|
| Individual Commitment Contract | Experimental | Subjects are offered an individual commitment contract for smoking cessation or weight loss and receive no additional information treatments. |
|
|
| Individual Monetary Rewards | Behavioral | Individuals eligible for a $100 monetary reward (incentive) following verified smoking cessation or weight loss. |
|
| Individual Commitment Contract | Behavioral | Individuals will have the opportunity to create an individual commitment contract to quit smoking. They will have the option to set the stakes, start date, and (for weight loss contracts) target weight. |
|
| Information | Other | In the initial survey, participants will receive additional information treatments on the likelihood of success of the different incentives and contracts, with the goal of shifting "naives" to "sophisticates." |
|
| D012816 |
| Signs and Symptoms |
| D013568 | Pathological Conditions, Signs and Symptoms |