Ontology mapping between HL7 versions 2 and 3 and OpenEHR for observations messages

Interoperability between health informatics standards enables new best-ofbreed solutions to evolve from legacy health information systems, and enables a healthcare data model to evolve and be enriched. In this paper we show that a lightweight XSLT framework can be used to achieve interoperability between HL7 versions 2 and 3 and HL7 version 3 and OpenEHR. We present the necessary transformations between terminology and structure in these standards as an exercise in ontology mapping. We discuss our experience with respect to clinical observation messaging.