Evaluation of the CCAM Hierarchy and Semi Structured Code for Retrieving Relevant Procedures in a Hospital Case Mix Database.

In France, clinical procedures are coded with the French procedures classification (Classification Commune des Actes Médicaux, CCAM) and recorded in every hospital. CCAM uses hierarchical semi-structured codes which describe procedures (topography, action, access mode and/or technique). This amount of information could be analyzed and used for clinical and medico-economic evaluation. But relevant and practical data searches are difficult. In this paper we present a use case about searching for endoscopic activities in a case mix database to evaluate the relevance of the hierarchical organization and semi structured codes of CCAM in order to retrieve data already coded using this controlled vocabulary. Precision was 0.79 and recall 0.84 in the hierarchical search whereas precision was 0.94 and recall was 0.81 using part of the code related to access mode and/or technique. We discuss a revision of the CCAM by the use of an existing modeling (from the GALEN project) and better knowledge representation for each procedure.