Foundations for validation of quantitative analytical methods in the clinical laboratory.

This article explores federal requirements for validation of analytical methods and available resources. We focus on the contributions of the National Committee for Clinical Laboratory Standards to the problems of method validation. Illustrations are selected from the Committee's EP5-T Evaluation of Precision, EP10-T Preliminary Evaluation of Clinical Chemistry Methods, EP11 Uniformity of Claims, and the National Reference System for the Clinical Laboratory. We also include a list of applicable national and international organizations. Calcium assay by atomic absorption spectrometry using an imprecise diluter illustrates the application of the evaluation protocols as a method validation tool.