What Do Workplace Wellness Programs Do?

We designed a large-scale, randomized controlled trial (RCT) to evaluate workplace wellness

The Illinois Workplace Wellness Study is a large, randomized controlled trial of a comprehensive wellness program at the University of Illinois at Urbana-Champaign. The study is designed to:

  • Examine the effects of financial incentives on workplace wellness participation
  • Investigate who benefits from workplace wellness programs
  • Estimate the causal effect of workplace wellness on employee health care costs, health behaviors, well-being, and productivity
  • Test for peer effects in wellness program participation

The Illinois Workplace Wellness Study aims to inform the national conversation surrounding workplace wellness, drawing from strong scientific evidence and an innovative study design. The study's findings will empower employers, public health professionals, and policymakers to make more informed decisions regarding the implementation of workplace wellness programs throughout the United States. Below we summarize the first set of results from the multi-year study.

Paying employees to participate in health screenings works, but only to a point

Participation Response to Incentives

Health screening participation, by size of incentive

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This figure shows the share of employees who completed both a biometric health screening and health risk assessment in each treatment arm. The treatment arms differed only in the size of the incentive offered for completion: $0, $100, or $200. Each treatment arm has a total 1,100 members. Vertical bars display 95% confidence intervals on the difference in shares relative to the $0 group.

After 1 year, workplace wellness did not change health care costs

Medical Spending Effects

Post-intervention, average monthly medical spending

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This figure shows average monthly medical spending among employees in the control and treatment groups, during the post-intervention period from August 2016 to July 2017. The control and treatment groups include 1,031 and 2,207 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the control group.

After 1 year, workplace wellness also did not change employees' measured health behaviors

Gym Usage Effects

Post-intervention average annual gym visits

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This figure shows average annual gym visits for the control and treatment groups, during the post-intervention period from August 2016 to July 2017. The control and treatment groups include 1,534 and 3,300 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the control group.

Running Event Effects

Post-intervention running event participation

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This figure shows the share of employees in the control and treatment groups who participated in the 2017 Illinois Marathon/10K/5K. The control and treatment groups include 1,534 and 3,300 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the control group.

Employees who chose to participate in workplace wellness already had lower health care costs before the program began

Prior Medical Spending

Pre-intervention average medical spending among treatment group members

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This figure shows average monthly medical spending among those in the treatment group who did and did not choose to complete a screening. The data are from the pre-intervention period August 2016 to July 2016, and thus are not a product of the intervention. The screened and non-screened groups include 869 and 1,318 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the non-screened group.

Employees who chose to participate in workplace wellness were already healthier before the program began

Prior Gym Usage

Pre-intervention average annual gym visits among treatment group members

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This figure shows average annual gym visits famong those in the treatment group who did and did not choose to complete a screening. The data are from August 2015 to July 2016, and thus are not a product of the intervention. The screened and non-screened groups include 1,452 and 1,848 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the non-screened group.

Prior Running Experience

Pre-intervention running event participation among treatment group members

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This figure shows the share of employees who participated in the Illinois Marathon/10K/5K among those in the treatment group who did and did not choose to complete a screening. The data are from 2014 to 2016, and thus are not a product of the intervention. The screened and non-screened groups include 1,452 and 1,848 members, respectively. Vertical bars display 95% confidence intervals on the difference in means relative to the non-screened group.

But a lot of questions remain about if and how these programs work

We have observed results for only the first year of our intervention. We are continuing to collect data to evaluate effects in the second and third years. For more details on our first set of results, see the full study.

Visit here to find out about the future release of additional results on biometric outcomes, disease management, longer run results, and peer effects, as well as publicly available data.