Apart from its use for clinical controlling and performance statistics it is a basis for inpatient claims processing within the German Diagnosis-related Groups (G-DRG) system.
Yearly OPS releases are produced by DIMDI (Deutsches Institut für Medizinische Dokumentation und Information).
Besides OPS, G-DRG also requires disease codes based on ICD-10-GM is (the German Modification of the current WHO standard).
Originally a subset of ICPM, OPS-301 has been expanded by a significant number of national codes since version 2.0 (effective in 2001).
The OPS classification gained an enormous importance with the introduction of the G-DRG flat rate system in 2004.