Objective To identify the medical, demographic, and behavioral factors associated with a reduction of body mass index percent of the 95th percentile (BMIp95) after 1 year for patients receiving care at a tertiary care obesity management clinic. Study design A retrospective review of data from first and 12 AE 3-month follow-up visits of subjects aged 8-17 years with obesity. Data included anthropometrics, demographics, medical/psychological history, reported diet patterns, and participation in moderate/vigorous physical activity. After analyzing factors associated with 1-year follow-up, we used a forward conditional logistic regression model, controlling for subject's sex, to examine associations with a BMIp95 ³5-point decrease at 1 year. Results Of 769 subjects, 184 (23.9%) had 1-year follow-up. Boys more often had follow-up (28.4% vs girls, 19.1%; P = .003). The follow-up sample was 62.0% male, 65.8% Hispanic, and 77.7% with public insurance; 33.2% achieved a ³5-point decrease in BMIp95. In regression results, the ³5-point decrease group was more likely to have completed an initial visit in April-September (OR 2.0, 95% CI 1.1-3.9); have increased physical activity by 1-2 d/wk (OR 3.4, 95% CI 1.4-7.8) or increased physical activity by ³ 3 d/wk at 1 year (OR 2.7, 95% CI 1.1-6.3); and less likely to have been depressed at presentation (OR 0.4, 95% CI 0.2-0.9). Demographic and dietary factors were not significantly associated with BMIp95 group status. Conclusions Strategies improving follow-up rates, addressing mental health concerns, and promoting yearround physical activity are needed to increase the effectiveness of obesity management clinics. (J Pediatr 2019;212:35-43). O ver the last decade, the prevalence of pediatric obesity has continued to climb, and in 2016, 18.5% of children in the US were obese. 1 Trends toward increasing body mass index (BMI) are not expected to slow. A recent study projected that 57.3% of today's children will be obese by the age of 35 years. 2 Pediatric obesity has been shown to have many negative effects on children's metabolic, cardiovascular, pulmonary, and psychological health. 3-7 Without intervention, the majority of children and teens with obesity will have obesity as adults. 2,8 Overall, treatment of pediatric obesity has had limited success even with intensive lifestyle interventions. The Institute of Medicine guidelines recommend at least 26 contact hours for a pediatric obesity intervention to be effective, and this is based on behavioral interventions with a modest drop in BMI z scores ranging from 0.05 to 0.59. 9 Behavioral interventions largely have been successful in stabilizing participants' BMIs, which is unlikely to achieve metabolically beneficial effects. 10-13 The Pediatric Obesity Weight Evaluation Registry (POWER) study of children with obesity found a 5-point reduction in BMI percent of the 95th percentile (BMIp95) to be associated with improved cardiometabolic risk. 14 The purposes of this study are to identify differences between patients with and without a 1...