APPLICATION OF SIX SIGMA METHOD IN QUALITY CONTROL OF SOME BIOCHEMICAL TESTS AT THE LABORATORY DEPARTMENT OF CAN THO DERMATO - VENEREOLOGY HOSPITAL
Main Article Content
Abstract
Background: Laboratory test results account for 60-70% of clinical decision-making, making test quality essential in healthcare. The Six Sigma method is an effective tool for quality management in testing, based on total allowable error (TEa), allowable bias, and coefficient of variation (CV%). Six Sigma aids in error detection, process improvement, and achieving the highest quality goals. Objectives: To apply the Six Sigma Method to Assess Quality Control Effectiveness in Biochemistry Testing at the Laboratory Department of Can Tho Dermato – Venereology Hospital. Materials and methods: A cross-sectional study was conducted on internal and external quality control results for selected biochemistry tests from February 2024 to October 2024 at Can Tho Dermato - Venereology Hospital. Results: The evaluation of biochemical test precision on the Monarch 600 analyzer showed that most tests met acceptable precision limits, with CV% ranging from 0.90% to 5.27% at QC Level 1, and from 0.02% to 3.45% at QC Level 2. However, HDL-Cholesterol and Uric Acid exceeded the maximum allowable imprecision at QC Level 2. Accuracy evaluation revealed that AST, Bilirubin Total, and Creatinine exceeded allowable bias limits. Six Sigma analysis identified Bilirubin Total, HDL-Cholesterol, and Triglycerides as needing optimization due to sigma values below the ideal threshold of 3. Improvements are required for consistency and accuracy in these tests. Conclusions: This study highlights the importance of quality control (QC) in clinical biochemistry testing through the Six Sigma method. The results show that some tests meet international standards, while others, such as Creatinine and Total Bilirubin, require improvement in accuracy. Data collected from IQC and EQC help build a comprehensive database, but errors still remain. Laboratories need to improve processes, train staff, and regularly check equipment to enhance the quality of tests and healthcare.
Keywords
Total Allowable Error (TEa), Allowable Bias, Coefficient of Variation (CV), Six Sigma
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References
2. Westgard J.O, Westgard S.A. Basic Quality Management Systems. Madison WI. 2014.171-189.
3. Westgard, J. O., & Groth, T. Power functions for statistical control rules. Clinical Chemistry. 1979. 25(6), 863-869. https://doi.org/10.1093/clinchem/25.6.863.
4. Yang, F., Wang, W., Liu, Q., Wang, X., Bian, G., Teng, S., & Liang, W. The application of Six Sigma to perform quality analyses of plasma proteins. Annals of Clinical Biochemistry. 2020. 57(2), 121-127. https://doi.org/10.1177/0004563219892023.
5. Hens, K., Berth, M., Armbruster, D., & Westgard, S. Sigma metrics used to assess analytical quality of clinical chemistry assays: importance of the allowable total error (TEa) target. Clinical Chemistry and Laboratory Medicine (CCLM). 2014. 52(7), 973-980. https://doi.org/10.1515/cclm-2013-1090.
6. Zhou, B., Wu, Y., He, H., Li, C., Tan, L., & Cao, Y. Practical application of Six Sigma management in analytical biochemistry processes in clinical settings. Journal of clinical laboratory analysis. 2020. 34(1), e23126. https://doi.org/10.1002/jcla.23126.
7. Trinh Thi Phuong Dung, Nguyen Thi Thanh Ngan, Hoang Thi Xuan, Nguyen Quynh Giao, Nguyen Tran Phuong, Tran Thi Chi Mai. Application of Six Sigma in Assessment a Laboratory’s performance in Analytical phase. Vietnam Medical Journal. 2021. 520(2), 240244. https://doi.org/10.51298/vmj.v520i2.4177.
8. Vo Thanh Tri, Bui Thi An, Le Trung Tin, Tran Thi Truc Linh, Vo Thi Minh Tho, Nguyen Huyen Tran, Nguyen Thi Bao Ha. Application of the Six Sigma Method Evaluating the Quality of Biochemical Tests at Phuong Chau International Hospital. Can Tho Journal of Medicine and Pharmacy. 2023. (69), 43-50. https://doi.org/10.58490/ctump.2023i69.2225.
9. Liu, Q., Fu, M., Yang, F., Liang, W., Yang, C., Zhu, W., ... & Zhao, C. Application of Six Sigma for evaluating the analytical quality of tumor marker assays. Journal of Clinical Laboratory Analysis. 2019. 33(2), e22682. https://doi.org/10.1002/jcla.22682.
10. Taher, J., Cosme, J., Renley, B. A., Daghfal, D. J., & Yip, P. M. A novel Sigma metric encompasses global multi-site performance of 18 assays on the Abbott Alinity system. Clinical Biochemistry. 2019. 63, 106-112. doi: https://doi.org/10.1016/j.clinbiochem.2018.10.003.
11. Thakur, V., Akerele, O. A., Brake, N., Wiscombe, M., Broderick, S., Campbell, E., & Randell, E. Use of a Lean Six Sigma approach to investigate excessive quality control (QC) material use and resulting costs. Clinical Biochemistry. 2023. 112, 53-60. https://doi.org/10.1016/j.clinbiochem.2022.12.001.
12. Phan Thi Thanh Hai, Nguyen Thi Lan Huong, Nguyen Thi Thu Huyen, Nguyen Thi Yen. Quality control in clinical chemistry laboratory based on the sigma metrics. Journal of 108 Clinical Medicine and Pharmacy. 2022. 17, 149-156. https://doi.org/10.52389/ydls.v17iDB.1424.