Abstract
Workplace wellness programs aim to improve employee health and lower health care spending. Recent randomized studies have found modest short-run effects on health behaviors, but longer-run effects remain poorly understood. We analyzed a clustered randomized trial of a workplace wellness program implemented at a large multisite US employer. Twenty-five randomly selected treatment worksites received the program, with five of the worksites added at the trial's midpoint, and 135 randomly selected control worksites did not. The program included modules on nutrition, physical activity, and stress reduction, implemented by registered dietitians. The effects of program availability and participation were assessed. At the end of three years, employees at the treatment worksites had better self-reported health behaviors, including a higher rate of actively managing their weight. No significant differences were found in self-reported health; clinical markers of health; health care spending or use; or absenteeism, tenure, or job performance. Improvements in health behaviors after three years were similar to those at eighteen months, but the longer follow-up did not yield detectable improvements in clinical, economic, or employment outcomes.