Quality specifications derived from objective analyses based upon clinical needs.

The well-informed physician should be the best to judge the analytical quality needed for a specific clinical action. By presenting the physicians with well-designed case histories, it is possible to extract the clinical knowledge pertinent to analytical quality. The clinicians are asked which changes in the concentration of an analyte will cause them to change actions concerning the patient. It must be possible to detect these changes with a certain probability and this presupposes a certain analytical quality which can then be calculated. It is important that a strict methodology both for constructing case histories and for calculation of the required analytical quality is used.