[Appropriateness of medical procedures: measurements and relations with needs and access to health care].

Efforts to reduce cost expenditures and improve quality of care have raised some concern over the recent years as to the appropriateness of medical procedures. However, the relationships between the appropriateness of medical procedures, the need for such procedures and access to health care have not been described in detail. The appropriateness of medical procedures is usually measured on the basis of procedures actually performed. We present a critical appraisal of this type of measurement. From a population point of view, measurement of appropriateness does not actually reflect simply those procedures which have been performed, but rather involves three parameters: needs for a particular procedure, access to the procedure by those who need it, and non performance of the procedure among those who do not need it. This analysis revealed three consequences. First, there is an inverse relationship between access to a procedure among subjects who need the procedure and the appropriateness of such a procedure among those who do not need it. Secondly, comparisons of appropriateness rates between individual facilities or between regions must take into account the need for this procedure in the general population. Finally, it is possible to observe similar rates of procedure performance between regions or social groups despite major regional or social differences in appropriateness and access to health care.