Yanpanich V, Duangdee C, Kunsombat J. Application of Sigma Metrics for the Assessment and Modification of Quality Control in Clinical Chemistry Laboratory of Hospital for Tropical Diseases. Vajira Med J [internet]. 2020 Dec. 15 [cited 2026 Sep. 18];64(6):411-8. available from: https://he02.tci-thaijo.org/index.php/VMED/article/view/239894