The Potential for Providing Treatment on an Outpatient Rather Than Inpatient Basis: A Nationwide Analysis of Hospital Discharge Data in Germany for the Year 2022.

Background: In an expert analysis by the IGES Institute, it was examined which inpatient hospital treatments could also be carried out on an outpatient basis. A method of determining the feasibility of performing any particular treatment in the outpatient setting based on routine documentation was proposed in the report. A new version of the German catalogue of operations that can be per - formed on an outpatient basis and other outpatient procedures (the AOP catalogue) was issued accordingly. In addition, sector-blind (hybrid DRG) reimbursement of selected treatments was introduced, i.e., the amount of the reimbursement is now the same regardless of whether the treatment is provided on an inpatient or outpatient basis.

Methods: The present analysis is based on German nationwide hospital discharge data from 2022. It was calculated how many inpatient treatments could have been carried out on an outpatient basis according to the criteria of the IGES report and the AOP catalogue, and how many cases would fall under hybrid DRGs.

Results: Of 14.8 million inpatient treatment cases (excluding deliveries and neonates), 7.2% were identified that might have been provided on an outpatient basis according to both models, and a total of 17.3% and 21.8%, respectively, according to the IGES model or the AOP catalogue. The estimated number of potential hybrid DRG cases was 153 000, or 1.0%.

Conclusion: Both the IGES model and the AOP catalogue identified a relevant potential for providing treatment on an outpatient rather than inpatient basis. However, the overlap between the two approaches is small. Further development of the AOP catalogue appears necessary for the more accurate identification of treatment cases that can be provided in the outpatient setting. The extent to which the new AOP catalogue and hybrid DRG remuneration can promote the provision of outpatient rather than inpatient care will need to be determined in future analyses.