A methodological framework for the conversion of procedure classifications

During the adaptation of the Australian Refined Diagnosis Related Groups for Germany mapping tables between procedure classifications were needed. The mapping between the German OPS-301 2.0 and the Australian MBS-Extended should transfer the Australian expertise by keeping a well-established terminology system.

A methodological framework for the development of mapping tables had been developed based on the model for representation of semantics provided by the European Committee of Standardization. Two approaches were used; the concept-based approach from OPS-301 2.0 to MBS-Extended and the class-based approach the other way round. A conversion had to be identified between 23,160 classes of the OPS-301 2.0 and 6,328 classes of the MBS-Extended in two asymmetrical mapping tables.

The class-based approach leads to a low number of 6,980 conversions but misses 82.6% of the classes of the OPS-301. Because of domain incongruencies and missing domain completeness of the OPS-301 2.0 for non-operative procedures 15.7% of the MBS-Extended-classes remain without conversion. The concept-based approach leads to a slightly higher mean number of conversions per class of 1.35 in comparison to 1.31 with the class-based approach. But it was possible to find conversions for 99.5% of the OPS-301 2.0-classes. 16.3% of the DRG-relevant classes of the MBS-Extended were missed.

The class-based approach was not useful, because the MBS-Extended is significantly broader than the OPS-301 2.0. An external validation study for the direction OPS-301 2.0 to MBS-Extended revealed a satisfactory quality. The empirical and the reference-based approach are important alternatives to the ones used in this project. There are clear criteria about the appropriate application area for the methodological approaches presented here.