Achieving minimum caseload requirements--an analysis of hospital discharge data from 2005-2011

The German Federal Joint Committee (the highest decision-making body of physicians and health insurance funds in Germany) has established minimum caseload requirements with the goal of improving patient care. Such requirements have been in place for five types of surgical procedure since 2004 and were introduced for total knee endoprosthesis surgery in 2006 and for the care of low-birth-weight neonates (weighing less than 1250 g) in 2010.

We analyzed data from German nationwide DRG statistics (DRG = diagnosis-related groups) for the years 2005-2011. The procedures that were performed were identified on the basis of their operation and procedure codes, and the low-birth-weight neonates on the basis of their birth weight and age. The treating facilities were distinguished from one another by their institutional identifying numbers, which were contained in the DRG database.

In 2011, there were 172 838 hospitalizations to which minimum caseload requirements were applicable. 4.5% of these took place in institutions that did not meet the minimum requirement for the procedure in question. The percentage of institutions that did not meet the minimum caseload requirement for complex pancreatic surgery fell significantly from 64.6% in 2006 to 48.7% in 2011, and the percentage of pancreatic surgery cases treated in such institutions fell over the same period from 19.0% to 11.4%. A significant reduction in the number of institutions treating low-birth-weight neonates was already evident before minimum caseload requirements were introduced. For all other types of procedure subject to minimum caseload requirements, there has been no significant change either in the percentage of institutions meeting the requirements or in the percentage of cases treated in such institutions.

After taking account of the potential bias due to the identification of institutions by their institutional identifying numbers, we found no discernible effect of minimum caseload requirements on care structures over the seven-year period of observation, with the possible exception of a mild effect on pancreatic procedures.