Implementation and effects of Germany's minimum volume regulations: results of the accompanying research

Abstract

Introduction: Since 2004, Germany has had legal minimum volumes for five surgical interventions (kidney, liver, and stem cell transplantations and complex pancreatic and esophageal interventions). In 2006, minimum volumes for total knee replacement were added. On behalf of the Federal Joint Committee we evaluated the implementation of the minimum volumes and their effects on health service structure, hospitals, and outcome quality.

Methods: We analyzed hospital surveys and secondary data from quality reports for 2004, the Institute for the Hospital Remuneration System, and the Federal Agency for Quality Assurance.

Results: In 2006, the minimum volume regulations affected about half of all acute-care hospitals and about 146 000 hospital cases. Depending on the intervention, 10% to 60% of the hospitals with 1% to 31% of the patients performed the procedures yet failed to attain the minimum volumes. The number of hospitals providing the services did not change between 2004 and 2006, so nationwide coverage remained virtually unchanged. Regarding outcomes, only data for total knee replacement were available. One of three analyzed indicators of outcome, wound infections, showed the introduction of the minimum volumes to be associated with better results for higher numbers of cases.

Discussion: To date, the minimum volumes have affected health care only marginally. Further monitoring of the effects of the minimum volumes requires prospective definition of essential indicators of outcome and access.

Keywords: case number development; health care research; integrated care; minimum volumes; quality assurance.

Figure 1

Implementation of the minimal volumes: number of hospitals that performed procedures subject to minimal volumes in 2004 and could have done so in 2006 based on the number of interventions in 2004 (quality records or BQS data), planned to do so (hospital surveys), or actually did so (InEK data). MMV, Mindestmengenvereinbarung (Minimum Volumes Directive), Tx, transplantation; TKR, total knee joint replacement

Figure 2

Risk-adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for all hospitals in five case number categories for the outcome indicators "wound infection" and "wound hematoma/secondary hemorrhage" in TKR (BQS data 2006)