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 with a less-intensive intervention (Livin' My Weigh [LMW]) 6 months after program initiation. 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 on-site educational sessions. Generalized linear mixed models were conducted for weight change from baseline to 6 months post-program and using an intention-to-treat 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) with a BMI decrease of 0.20 kg/m(2) (P < 0.01) in INCENT and LMW, respectively. The differences between INCENT and LMW in weight loss and BMI reduction were not statistically significant. CONCLUSIONS:This study suggests that INCENT and a minimal intervention alternative may be effective approaches to help decrease the overall obesity burden within worksites.