The "normal range" problem in the practice of clinical pathology.
The reference values appropriate to diagnosis are different from those appropriate to therapy support. Therapy support frequently involves the comparison of a patient with a physiologically normal benchmark (normal range criteria). Diagnosis, on the other hand, usually requires criteria developed from studies in which patients with a certain disease are contrasted with other patients who present similar clinical findings but do not have the disease in question (disease referenced criteria). It is reasonable to suppose that pathologists would enhance patient care by reporting the reference values appropriate to the particular testing situation. If the purpose of testing is not known, both kinds of referenced values should be reported.
D019411:Clinical Laboratory Techniques / Q000706:statistics & numerical data*; D012016:Reference Values