IntroductionThe quality of healthcare in childhood and adolescence is of key importance, in order to foster a healthy development and to avoid chronic health problems. Yet, data for Germany regarding the quality of healthcare for this patient group are lacking. The QualiPäd research project aims to estimate the quality of outpatient healthcare for children and adolescents in Germany, focusing on common psychiatric and physical disorders.Methods and analysisQuality indicators for seven common physical and mental childhood and adolescent clinical conditions (attention deficit/hyperactivity disorder, asthma, atopic dermatitis, depression, otitis media, conduct disorder/oppositional defiant disorder, tonsillitis) will be developed and ratified by experts, using the RAND/UCLA Appropriateness Method.Initially, 1400 medical records of children and adolescents with one of the aforementioned clinical conditions will then be randomly drawn from 40 outpatient practices in the German federal state of Hessen. The records will then be assessed regarding their adherence to the respective quality indicators. Based on this, the percentage of appropriate and inappropriate (eg, wasteful) healthcare of all clinical conditions (primary endpoint) will be estimated. Additionally, possible factors influencing the quality of care (eg, patient characteristics, type of condition, type of practice) will be identified using generalised estimation equation models.Ethics and disseminationThis study will show for which of the studied clinical conditions and/or patients improvement of quality of care is necessary within the German health system. Also, the quality indicators designed for the study can afterwards be implemented in regular care and thus enable regular reporting of the outpatient care of this target group. The authors plan to disseminate their findings through international, peer-reviewed scientific publications, and through presentations at national and international paediatric and child psychiatric conferences.Trial registration numberDRKS00022408.