[INTEGRATE-ADHD: Comparison and Integration of Administrative and Epidemiological ADHD Diagnosis Data through Clinical Assessment - Presentation of the Project].

As one of the most frequently diagnosed mental disorders in children and adolescents with sometimes serious individual, family and social consequences, attention deficit/hyperactivity disorder (ADHD) is highly relevant to society and health policy. In Germany, data from statutory health insurance companies has reported increasing ADHD diagnosis prevalence rates over years, while epidemiological data has shown constant and recently even decreasing prevalence rates. The clinical validity of diagnoses from either data sources is unknown. In the framework of the consortium project INTEGRATE-ADHD, 5461 parents of children aged 0 to 17 years with a confirmed administrative ADHD diagnosis insured with the third-largest German statutory health insurance provider (DAK-Gesundheit) in at least one quarter of 2020 were surveyed with the questionnaires from the epidemiological German Health Interview and Examination Survey (KiGGS study) and its in-depth module on child mental health (BELLA study) on their child's ADHD diagnosis and symptoms and on other topics, including comorbidity, utilisation of healthcare services, quality of care and satisfaction, psychosocial risk and protective factors and health-related quality of life. In addition, a subsample of 202 children and adolescents with a clinical diagnosis based on the AMWF S3 guideline on ADHD was analysed. An important aim of the project is to use data linkage on person-level to identify possible causes for the often divergent prevalence estimates from epidemiological and administrative data and to integrate and validate the data sources using a guideline-based clinical diagnosis, thereby contributing to a more accurate population-based prevalence estimate of ADHD in children and adolescents and clarifying actual or supposed contradictions between the data sources. The INTEGRATE-ADHD data linkage project combines administrative, epidemiological and clinical ADHD diagnosis data to create a "three-dimensional view" of the ADHD diagnosis. The results will be used to identify fields of action for healthcare policy and self-administration in the German healthcare system and to derive recommendations for the actors and stakeholders in the field of ADHD. The first results will be published in 2024.