International Journal of Medical Laboratory Research (IJMLR)

A STANDARDIZED FRAMEWORK FOR QUANTITATIVE ANALYTICAL METHOD VERIFICATION TO ENSURE HIGH QUALITY REPORTING OF PATIENTS' SAMPLES IN A MEDIUM SIZED LABORATORY ASSOCIATED WITH TERTIARY CARE HOSPITAL

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RR Datta, LK Sharma, M Srivastava, N Sharma

 

ABSTRACT: Introduction: Method verification and validation is an individual laboratory’s responsibility in view of providing patient care with high reliability and as per requisite of regulatory bodies in health care domain.In this context, the study laboratory validates all new tests before introducing it for patient sample testing by verifying analytical accuracy, inter-assay and intra-assay precision, manufacturer’s reference intervals and linearity range. Materials and Methods: The process of validation is being carried out using certified quality control material covering both normal and abnormal ranges of the analyte (Procalcitonin). Inter-assayand Intra-assay precision verification was performed wherein each level of the quality control material is processed 3 times per run for 5 days generating 15 replicates and 20 times in a single run respectively. Verification of Analytical Accuracy was expressed as recovery, calculated as the percentage betweenaverage measurement results and true value of the reference material. Reference Rangehas been verified by processing samples from20 healthy individuals.  For linearity check, high value sample above linearityrange is progressively diluted, until it crosseslower limit of linearity and results expressed as recovery percentage. Results: Precision verification (inter and intra assay), accuracy, reference range and linearity verification were within the acceptable criteria defined by the laboratory (manufacturer’s claim in case of procalcitonin). The test method was thus accepted to be used for patient sample testing. Conclusion: Method validation is an imperative part of maintaining laboratory tests quality. This study highlights the role of method validation as a vital step towards quality patient care. Individual laboratory can define its own method validation protocol in a cost-effective way.

 

KEY WORDS: Method validation, intra-assay precision, inter-assay precision, accuracy, linearity,   reference range

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