Elion-Gerritzen, W.E.

laboratory value clinician range result limit variability level action hospital difference control intralaboratory variability action levels patient constituent intralaboratory sample table change physician error study figure number variation action level group quality range values question column cholesterol answer laboratory results chapter survey calcium point decision performance glucose determination report creatinine serum laboratory performance graph chemistry order situation precision protein two-sample plot population mmol /1 reference example target value dispersion laboratory directors quality control laboratorium requirement chern literature target potassium measurement material concentration director hemoglobin factor hospital laboratory interpretation control materials individual program effect