Kiểm soát chất lượng xét nghiệm hóa sinh dựa vào thang điểm sigma

Abstract

Objective: To evaluate quality of biochemical tests based on Sigma scale, thereby providing a suitable and highly effective quality control procedures. Subject and method: Applied experimental, descriptive cross-sectional study, conducted on Architect C16000 chemmistry analyzer of Abbott (USA) at Department of Biochemistry, laboratory Center, 108 Military Central Hospital from October 22, 2021 and July 24, 2022. The evaluated testing included 22 tests: Alb, ALT, Amy, AST, Bil-D, Bil-TP, Ca, Cl, Cho, CK, Fe, GGT, Glu, HDL-C, LDL-C, Lip, K⁺, Na⁺, TP, Tri, Ure, AU. The performance of these tests was evaluated using a sigma scale calculated from the total allowable error (TEa), bias and coefficient of variation (CV) of each test. Result: All analytes had sigma values of more than 3 (the minimum accepted performance). The sigma values of albumin, amylase, AST, direct bilirubin, total bilirubin, calcium, cholesterol, CK, GGT, glucose, HDL-C, Fe, LDL-C, potassium, triglycerides, uric acid were greater than 6, while chloride, lipase, BUN had sigma values in the range of 4 to 6. Sigma scores of ALT and sodium were between 3 and 4. Conclusion: This research demonstrates that all of 22 analytes get sigma values greater than 3, the majority of them (17 analytes, making up 77.3%) have at least sigma values of 6. Sigma value act as a guide for designing QC procedures in the laboratories, by monitoring more strictly for test with low sigma and by minimizing the unnecessary QC monitoring for test with high sigma.