Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data

Background: Six Sigma is a popular quality management system that enables continuous monitoring and improvement of analytical performance in the clinical laboratory. We aimed to calculate sigma metrics and quality goal index (QGI) for 17 biochemical analytes and compare the use of bias from internal...

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Main Authors: Çevlik Tülay, Haklar Goncagül
Format: Article
Language:English
Published: Society of Medical Biochemists of Serbia, Belgrade 2024-01-01
Series:Journal of Medical Biochemistry
Subjects:
Online Access:https://scindeks-clanci.ceon.rs/data/pdf/1452-8258/2024/1452-82582401043Q.pdf
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author Çevlik Tülay
Haklar Goncagül
author_facet Çevlik Tülay
Haklar Goncagül
author_sort Çevlik Tülay
collection DOAJ
description Background: Six Sigma is a popular quality management system that enables continuous monitoring and improvement of analytical performance in the clinical laboratory. We aimed to calculate sigma metrics and quality goal index (QGI) for 17 biochemical analytes and compare the use of bias from internal quality control (IQC) and external quality assurance (EQA) data in the calculation of sigma metrics. Methods: This retrospective study was conducted in Marmara University Pendik E&R Hospital Biochemistry Laboratory. Sigma metrics calculation was performed as (TEa-bias)/CV). CV was calculated from IQC data from June 2018 - February 2019. EQA bias was calculated as the mean of % deviation from the peer group means in the last seven surveys, and IQC bias was calculated as (laboratory control result mean-manufacturer control mean)/ manufacturer control mean) x100. In parameters where sigma metrics were <5; QGI=bias/1.5 CV) score of <0.8 indicated imprecision, >1.2 pointed inaccuracy, and 0.8-1.2 showed both imprecision and inaccuracy. Results: Creatine kinase (both levels), iron and magnesium (pathologic levels) showed an ideal performance with ≥6 sigma level for both bias determinations. Eight of the 17 parameters had different sigma levels when we compared sigma values calculated from EQA and IQC derived bias% while the rest were grouped at the same levels. Conclusions: Sigma metrics is a good quality tool to assess a laboratory's analytical performance and facilitate the comparison of the assay performances in the same manner across multiple systems. However, we might need to design a tight internal quality control protocol for analytes showing poor assay performance.
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spelling doaj.art-7e245a4519ad42268217eb1cbd0e76de2024-02-08T22:37:02ZengSociety of Medical Biochemists of Serbia, BelgradeJournal of Medical Biochemistry1452-82581452-82662024-01-01431434910.5937/jomb0-430521452-82582401043QSix SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance dataÇevlik Tülay0Haklar Goncagül1Marmara University Pendik E&R Hospital, Biochemistry Laboratory, Istanbul, TurkeyMarmara University Pendik E&R Hospital, Biochemistry Laboratory, Istanbul, TurkeyBackground: Six Sigma is a popular quality management system that enables continuous monitoring and improvement of analytical performance in the clinical laboratory. We aimed to calculate sigma metrics and quality goal index (QGI) for 17 biochemical analytes and compare the use of bias from internal quality control (IQC) and external quality assurance (EQA) data in the calculation of sigma metrics. Methods: This retrospective study was conducted in Marmara University Pendik E&R Hospital Biochemistry Laboratory. Sigma metrics calculation was performed as (TEa-bias)/CV). CV was calculated from IQC data from June 2018 - February 2019. EQA bias was calculated as the mean of % deviation from the peer group means in the last seven surveys, and IQC bias was calculated as (laboratory control result mean-manufacturer control mean)/ manufacturer control mean) x100. In parameters where sigma metrics were <5; QGI=bias/1.5 CV) score of <0.8 indicated imprecision, >1.2 pointed inaccuracy, and 0.8-1.2 showed both imprecision and inaccuracy. Results: Creatine kinase (both levels), iron and magnesium (pathologic levels) showed an ideal performance with ≥6 sigma level for both bias determinations. Eight of the 17 parameters had different sigma levels when we compared sigma values calculated from EQA and IQC derived bias% while the rest were grouped at the same levels. Conclusions: Sigma metrics is a good quality tool to assess a laboratory's analytical performance and facilitate the comparison of the assay performances in the same manner across multiple systems. However, we might need to design a tight internal quality control protocol for analytes showing poor assay performance.https://scindeks-clanci.ceon.rs/data/pdf/1452-8258/2024/1452-82582401043Q.pdfsix sigma methodquality goal indexquality managementimprecisionbias
spellingShingle Çevlik Tülay
Haklar Goncagül
Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
Journal of Medical Biochemistry
six sigma method
quality goal index
quality management
imprecision
bias
title Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
title_full Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
title_fullStr Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
title_full_unstemmed Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
title_short Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
title_sort six sigma evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data
topic six sigma method
quality goal index
quality management
imprecision
bias
url https://scindeks-clanci.ceon.rs/data/pdf/1452-8258/2024/1452-82582401043Q.pdf
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