University Of Pennsylvania Weight Loss Study
This is a 4-arm, randomized controlled trial to evaluate the effectiveness of financial incentives to motivate and sustain long-term weight loss. The study will recruit eligible employees at a large health management company to participate in a 6-month weight loss program and have weight measurements for an additional 3-month follow-up period. The primary outcome measure in this randomized controlled trial will be pounds of weight lost. The experimental groups will include variations of deposit contracts (participants put their own money at risk, and lose that money if they fail to achieve their weight loss goal) and fixed payments. The use of deposit contracts is a powerful mechanism for inducing behavior change that is based on loss aversion, a psychological concept first described by Nobel Prize winner Daniel Kahneman and Amos Tversky in 1979. A deposit contract takes advantage of the fact that people typically feel the pain of a loss more than the pleasure of a gain, increasing ones motivation to reach a goal.
The study hypotheses are 1) mean weight loss will be greater in all intervention groups compared to the control group by the end of 24 weeks; and 2) individuals in the intervention groups will have a lower mean weight at the end of the 3-month follow-up period than individuals in the control group.
|Weight Loss||Behavioral: Deposit contract with a 1:1 match Behavioral: Deposit contract with a 2:1 match Behavioral: Deposit Contract with no match||Phase 3|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||University Of Pennsylvania Weight Loss Study|
- Change in weight [ Time Frame: 24 Weeks ]
- Average daily deposit value [ Time Frame: 24 weeks ]
|Study Start Date:||April 2011|
|Estimated Study Completion Date:||December 2016|
|Estimated Primary Completion Date:||December 2016 (Final data collection date for primary outcome measure)|
|No Intervention: 1|
Deposit contract with a 1:1 match
Behavioral: Deposit contract with a 1:1 match
Daily weigh-in for 24 weeks and if each daily goal met daily deposit amount is paid back with an additional matched amount equal to deposited amount. Final weigh-in at 36 weeks with no financial incentive or deposit made.
Deposit contract with a 2:1 match
Behavioral: Deposit contract with a 2:1 match
Daily weigh-in for 24 weeks and if each daily goal met daily deposit amount is paid back with an additional matched amount twice the amount equal to deposited amount. Final weigh-in at 36 weeks with no financial incentive or deposit made.
Experimental: Experimental 4
Deposit contract with no match
Behavioral: Deposit Contract with no match
Daily weigh-in for 24 weeks and if each daily goal met the daily deposit amount is paid back. Final weigh-in at 36 weeks with no financial incentive or deposit made.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01167634
|United States, Pennsylvania|
|University of Pennsylvania|
|Philadelphia, Pennsylvania, United States, 19104|
|Study Chair:||Kevin G. Volpp, MD, PhD||University of Pennsylvania|
|Study Director:||George Loewenstein, PhD||Carnegie Mellon University|
|Study Director:||Heather Schofield, MS||Harvard University|
|Principal Investigator:||Jeffrey T Kullgren, MD, MPH||University of Pennsylvania|