THE CLINICAL RELEVANCE OF ASSAY VALIDATION

Modern veterinary practice is becoming increasingly reliant on laborat ory test results obtained from analysis of patient specimens Assays th at had previously been unavailable to veterinary practitioners are now actively promoted in the literature and by laboratories. Practitioner s have readily added the new tools to their diagnostic repertoire. Met hods used in clinical laboratories to validate a new assay for clinica l use and thereby assure that results obtained from it are reliable, h owever, are not well-known. An understanding of the assay validation p rocess and the quality-control program used in a laboratory can help t he practitioner to make better medical judgments based on laboratory t est results. In this article, factors that affect the validation proce ss are presented, including variation, normality, reference ranges, so urces of error, and the determination of analytic goals. The rationale and procedural steps in assay validation and an overview of laborator y quality-control programs are discussed An explanation of validation terminology is provided, which, coupled with an increased knowledge of the validation process. will enable the practitioner to better interp ret test results, improve medical decision making, and optimize commun ications with the clinical laboratory.