Effectiveness of a Worksite-based Weight Loss Randomized Controlled Trial: The WORKSITE Study

OBJECTIVE: To determine the effectiveness of an individually-targeted Internet-based intervention with monetary incentives (INCENT) at reducing weight of overweight and obese employees when compared to a less-intensive intervention (Livin’ My Weigh [LMW]) 6-months after program initiation. DESIGN AND METHODS: Twenty-eight worksites were randomly assigned to either INCENT or LMW conditions. Both programs used evidence-based strategies to support weight loss. INCENT was delivered via daily e-mails over 12 months while LMW was delivered quarterly via both newsletters and onsite educational sessions. Generalized linear mixed models were conducted for weight change from baseline to 6-month post program and using an intention-to-treat (ITT) analysis to include all participants with baseline weight measurements. RESULTS: Across 28 worksites, 1,790 employees (M=47 years of age; 79% Caucasian; 74% women) participated. Participants lost an average of 2.27 lbs (p<0.001) with a BMI decrease of 0.36 kg/m(2) (p<0.001) and 1.30 lbs (p<0.01) and a BMI decrease of 0.20 kg/m(2) (p<0.01) in INCENT and LMW, respectively. The difference between INCENT and LMW group in weight loss and BMI reduction were not statistically significant. CONCLUSION: The current study suggests that INCENT and a minimal intervention alternative may be effective approaches to help decrease the overall obesity burden within worksites.