[Do German DRGs appropriately explain the resource consumption of hospitals? An empirical patient-level cost-data analysis across ten episodes of care].

AIM OF THE STUDY: The revenues of German hospitals are mainly determined by DRG-based payments. Therefore DRGs should appropriately explain the resource consumption of hospitals in order to avoid unintended consequences. So far little is known about the ability of German DRGs to adequately reflect the cost of a hospital stay.
METHODS: Regression techniques were applied using anonymised year 2008 cost and performance data of 50,156 cases from 29 hospitals for 10 common episodes of care in order a) to analyse the impact of patient and treatment characteristics on costs and b) to test if DRG variables are better in explaining resource consumption than this set of patient variables.
RESULTS: Depending on the episode of care, patient and treatment variables have a different impact on hospital costs. However, they are better in explaining resource consumption than the DRG variables for each episode of care. In addition, independent of the patient characteristics hospitals have an impact on costs which might be due to factors that are not considered by the DRG-system.
CONCLUSION: The analysis shows that the German DRG system requires further research. However, to date this is limited by poor data availability. Compared to other DRG systems the German system shows a weak performance. The incorporation of some of the used variables as well as an increasing international knowledge transfer might help to further improve the German DRG system. © Georg Thieme Verlag KG Stuttgart · New York.