Standards to support development of terminological systems for healthcare telematics

The Technical Committee on "Medical Informatics" of the European Committee for Standardization (CENT/TC251) is supporting developers of terminological systems in healthcare by a series of standards. The dream of "universal" c oding system was abandoned in favor of a coherent family of terminologies, diversified according to tasks; two ideas were introduced: (1) the "categor ical structure", i,e. a model of semantic categories and their relations wi thin a subject field and (2) the "cross-thesaurus", i,e. a system of descri ptors to build a systematic representation (called here "dissection") for e ach terminological phrase, coherent across diverse terminologies on a given subject field. The goal is to assure coexistence and interoperability land reciprocal supp ort for development and maintenance) to three generations of systems: (1) t raditional paper-based systems (first generation); (2) compositional system s built according to a categorical structure and a cross-thesaurus (second generation) and (3) formal models (third generation). Various scenarios are presented, on the exploitation of computer-based terminological systems. T he idea of "operational meaning" of terminological phrases within administr ative and organizational contexts and the idea of "task-oriented details" a re also introduced, to justify and exploit design constraints on terminolog ical systems.