University of Pennsylvania Prevention Research Center

A Randomized Controlled Trial of Incentives Vs. Environmental Strategies for Weight Loss


Obesity is the second leading cause of preventable death in the U.S. and has been linked to high blood pressure, type 2 diabetes, heart disease, and osteoarthritis. Research has shown that losing weight can improve risk factors and reduce the occurrence of chronic disease. In order to achieve these health outcomes, however, the weight loss has to be maintained and successful strategies for long-term maintenance are lacking. To address this knowledge gap, researchers at the University of Pennsylvania Prevention Research Center will conduct a study comparing different promising strategies to achieve weight loss and maintenance of weight loss in obese employee populations.

Researchers will recruit 328 employees from the City of Philadelphia, Independence Blue Cross, and Southeastern Pennsylvania Transportation Authority. The participants must be overweight or obese and have at least one other risk factor, such as high blood pressure, diabetes, or smoking. They will then be randomly assigned to receive one of the four approaches:

  1. Incentive approach – daily lottery type incentives linked to achieving weight loss goals.
  2. Environmental approach – individually tailored environmental strategies around food intake and physical activity.
  3. Incentive and environmental approach – a combination of incentives and environmental strategies.
  4. Standard approach (i.e., control group) – standard employee wellness benefits and weigh-ins every 6 months.

Researchers will compare the outcomes of the financial incentive and environmental approaches—both separately and together—with the standard approach. This assessment will help them determine which approach or combination of approaches work best for combatting obesity in obese employee populations. They will also assess the cost of each strategy and compare the cost differences between them relative to effectiveness (i.e., weight loss achieved).

This research aims to increase knowledge about effective strategies to achieve weight loss and the maintenance of weight loss among employee populations with high rates of obesity.

Project Identifier A Randomized Controlled Trial of Incentives Vs. Environmental Strategies for Weight Loss

Funding Source PRC Program

Project Status Active

Host Institution University of Pennsylvania

Health Topics Obesity & overweight | Physical activity | Nutrition

Research setting Worksite

Race or ethnicity No specific focus

Gender No specific focus 

Age group No specific focus 

Contact Information Center
UPenn Prevention Research Center
423 Guardian Drive
Philadelphia, PA 19104

Principal Investigator
Karen Glanz

PRC Deputy Director
Kevin Volpp
Phone: (215) 573-0270