gms | German Medical Science

Background: The utilization of claims data has been experiencing a substantial surge within the realm of health service research in Germany. This data presents a considerable potential for a diverse array of studies, attributable to its extensive sample size, the capacity for longitudinal analyses, and the absence of selection or recall bias. Nevertheless, a comprehensive, nationwide database encapsulating all data from the statutory health insurance (SHI) system remains absent in the current research landscape.

Objective: This study aims to describe the Deutsche Analysedatenbank für Evaluation und Versorgungsforschung (DADB) database and explore how different extrapolation strategies affect representativeness for the German population based on available demographic measures and morbidity groups.

Methods: The DADB comprises data from about 4.1 million insured individuals (5% of the German SHI population). The DADB encompasses an array of patient attributes, inclusive of both inpatient and outpatient diagnoses, articulated through the International Classification of Diseases (ICDs), along with drug prescriptions delineated by the Anatomical Therapeutic Chemical (ATC) classification system, and pertinent cost information. The database further extends to incorporate procedural data, denoted by the Operationen- und Prozedurenschlüssel (OPS), and Diagnosis-Related Groups (DRGs), thus providing a comprehensive overview of patient healthcare interactions. To improve the representativeness of the DADB for the SHI system, an age- and risk adjustment based on the Risikostrukturausgleich (RSA) is presented. Additionally, the implications of the adjustment on confidence intervals are discussed.

Results: In comparison to the German SHI population, the age and gender distribution of the DADB show a slightly younger population. The reported frequencies of morbidity groups align closely in magnitude between the two datasets, however, the DADB generally displays a slight diminution in these frequencies. After adjustment, these differences dimmish showing that the adjusted DADB is representative of the German SHI population.

Implication for research: The comprehensive and longitudinal overview of patient healthcare interactions can be used to build lines of therapy for medications in, among others, cancer and depression treatment.