In complex surgery, is there a correlation between the volume of services provided per hospital and the quality of treatment results? This is the question addressed in eight commissions on minimum volumes that the Federal Joint Committee (G-BA) awarded to the Institute for Quality and Efficiency in Health Care (IQWiG). The IQWiG report is now available for the sixth intervention to be tested, complex oesophageal surgery. According to the findings, there is a positive correlation between the volume of services and the quality of treatment results in complex esophageal surgery: In hospitals with larger case volumes, the survival probabilities for patients who underwent surgery are higher overall. In addition, complications occur less frequently there.
High-risk procedures performed as elective surgery
Esophageal operations, such as the complete or partial removal of the esophagus or the reconstruction of the oesophageal passage that is then necessary, are considered high-risk procedures that are usually performed as elective surgery. In most cases (2015: 83%), malignant neoplasms are the reason for the procedure. In 2018, the German Federal Statistical Office registered about 4700 of these complex oesophageal operations. About 9.5% of the patients who underwent surgery between 2010 and 2015 died in hospital in connection with the procedure.
At present, a minimum of ten procedures per hospital location and year applies in Germany for complex oesophageal surgery.
Positive correlation between volume of services and survival probabilities
The IQWiG project team identified 37 studies investigating the correlation between the volume of services and the quality of treatment results in complex oesophageal surgery - 30 of these studies contain usable data.
The analysis of the data showed that the survival probabilities for patients who underwent oesophageal surgery are higher overall in hospitals with larger case volumes. This can be inferred from the studies for the outcome "all-cause mortality" as well as for the outcomes "surgery-related mortality" and "in-hospital mortality". Furthermore, in hospitals with larger case volumes, treatment-related complications such as tearing or leakage of the reconstructed tissue (anastomosis insufficiency) occur less frequently.
In relation to the volume of services per surgeon, the available data show that with increasing routine for oesophageal surgery, fewer patients die in hospital and treatment-related complications occur less frequently.
There are no meaningful studies examining the effects of specific minimum case volumes introduced into the health care system for complex oesophageal surgery on the quality of treatment results.
Process of report production
In April 2019, the G-BA commissioned IQWiG to prepare the report on the correlation between the volume of services and the quality of treatment results for complex esophageal surgery in an accelerated procedure as a so-called rapid report. Interim products were therefore not published or made available for a hearing. This rapid report was sent to the contracting agency, the G-BA, in April 2020.