INDIcators for Clarifying the bAckground of exTreme Obesity in childRen

This observational study examines the genetic background of extreme childhood obesity — defined as a BMI above the 99.5th percentile — in children and adolescents aged 5–18 in Germany, using saliva samples and online questionnaires about hunger, family history, and growth patterns. The goal is to identify rare genetic mutations that cause severe early-onset obesity, which could lead to more targeted treatments. Children are identified through an existing growth registry (CrescNet) and contacted via their pediatricians to participate remotely. Participation involves a telemedical consultation, mailing a saliva sample, and completing questionnaires from home, with no clinic visit required. This summary was prepared to help patients understand the study in plain language.