Efficacy of a Weight-Loss Website Based on Positive Deviance A Randomized Trial Jennifer L. Kraschnewski, MD, MPH, Heather L. Stuckey, DEd, Liza S. Rovniak, PhD, MPH, Erik B. Lehman, MS, Madhu Reddy, PhD, Jennifer M. Poger, MEd, Donna K. Kephart, MHA, Elliot J. Coups, PhD, Christopher N. Sciamanna, MD, MPH Background: Web-based interventions for weight control could promote more-widespread dis- semination of weight-loss opportunities; however, they remain limited in effectiveness. Incorporat- ing weight-control practices used by individuals with long-term weight-loss success (“positive deviants”) may improve the effıcacy of web-based weight control interventions. Purpose: To evaluate the effıcacy of AchieveTogether, a web-based weight-loss intervention for adults based on user-generated weight-loss strategies from successful weight losers. Design: In 2009 –2010, participants were randomized to either a 12-week web-based intervention, AchieveTogether, or a wait-list control condition. Setting/participants: 100 overweight or obese adults participated in the study. Intervention: AchieveTogether was designed to help individuals implement weight control prac- tices used by others who successfully lost and maintained weight. Main outcome measures: The primary outcome was change in weight. Secondary outcomes in- cluded blood pressure, daily caloric intake, quality of life, and use of weight control practices. ANCOVA, with adjustment for baseline values on outcome measures, was used to assess differences between groups in primary and secondary outcomes. Statistical analyses were conducted in 2010 –2011. Results: Most participants were women (69.7%) and white (90.8%), with a mean age of 50.3 years and baseline BMI of 33.2; 88% completed post-program assessments. Mean weight loss among intervention participants was -1.4 kg (95% CI=-2.2, -0.5), compared with a mean weight gain of 0.6 kg (95% CI=-0.3, 1.4) in control participants (p0.01). Conclusions: User-generated weight-loss practices from “positive deviants” could promote weight control in web-based interventions; however, further research is needed to improve program effıcacy. Trial registration: This study is registered at ClinicalTrials.gov NCT00709501. (Am J Prev Med 2011;41(6):610 – 614) © 2011 American Journal of Preventive Medicine Introduction T he obesity epidemic has widespread adverse health and economic effects. 1 Internet-based weight-loss programs could help address the obe- sity epidemic, as they can be widely disseminated with low costs. Existing Internet-based weight-loss programs have largely promoted weight-loss strategies designed by health professionals, including goal-setting and feedback, and features to promote social interaction. 2–6 These pro- grams have had modest short-term effects, suggesting that exploring alternative approaches may be benefıcial. From the Department of Medicine, Pennsylvania (Kraschnewski, Stuckey, Rovniak, Poger, Sciamanna), Department of Public Health Sciences (Krasch- newski, Stuckey, Rovniak, Lehman, Kephart, Sciamanna), Penn State College of Medicine, Hershey; College of Information Sciences and Technology (Reddy), Pennsylvania State University, State College, Pennsylvania; and De- partment of Medicine (Coups), Cancer Institute of New Jersey, New Bruns- wick; Department of Health Education and Behavioral Science (Coups), University of Medicine and Dentistry of New Jersey Robert Wood Johnson Medical School, Piscataway, New Jersey Address correspondence to: Jennifer L. Kraschnewski, MD, MPH, Penn State College of Medicine, 500 University Drive, HO34, Hershey PA 17033. E-mail: jkraschnewski@hmc.psu.edu. 0749-3797/$36.00 doi: 10.1016/j.amepre.2011.08.012 610 Am J Prev Med 2011;41(6):610 – 614 © 2011 American Journal of Preventive Medicine • Published by Elsevier Inc.