Coding systems and controlled vocabularies for hospital information systems.

Modern healthcare information systems are requested to support an increasing interaction among professionals (inside and across the borders of the hospital) and a growing integration of specialised tasks (provision of care, reimbursement, document retrieval, optimisation of resource use, clinical audit, etc.). Coding systems were conceived and optimised independently for various specific purposes. They are now facing each other and thus conflicting into this new environment; the solution will be in a more application-independent representation of concepts. Developments are going towards three complementary directions: (i) to separate different functions about the management of terms and concepts, and thus to produce more specialised software components; (ii) to develop a new class of software which is able to manage terminological diversity without imposing uniformity; and (iii) to enhance reusability of concepts, and facilitate a spontaneous convergence among controlled vocabularies.