RESUMEN
Multimodal obesity treatments for children and adolescents generally showed only small to modest treatment effects and high dropout rates. Potential variations by patients' clinical and sociodemographic factors remain, however, largely unclear. For this reason, our study analyzed psychological, physical, and sociodemographic predictors of treatment success and adherence in a multimodal obesity treatment over 12 months. The intent-to-treat sample included n = 361 children and adolescents (ages 3-17 years), of which n = 214 or 59.28% of patients completed treatment. A younger age and, in the sensitivity analysis, additionally a greater eating disorder psychopathology and treatment initiation before COVID-19 pandemic predicted greater BMI-SDS reductions (Body Mass Index-Standard Deviation Score). In contrast, predictors of treatment adherence were not found. The results underline the importance of early treatment of juvenile obesity. Additionally, eating disorder psychopathology includes restrained eating, which implies the ability to self-regulate eating behavior and therefore may have a positive effect on the treatment goal of controlled food intake. Challenges from altered treatment procedures due to the COVID-19 pandemic nonetheless remain.