Quality control review: implementing a scientifically based quality control system
Abstract
This review focuses on statistical quality control in the context of a quality management system. It describes the use of a 'Sigma-metric' for validating the performance of a new examination procedure, developing a total quality control strategy, selecting a statistical quality control procedure and monitoring ongoing quality on the sigma scale. Acceptable method performance is a prerequisite to the design and implementation of statistical quality control procedures. Statistical quality control can only monitor performance, and when properly designed, alert analysts to the presence of additional errors that occur because of unstable performance. A new statistical quality control planning tool, called 'Westgard Sigma Rules,' provides a simple and quick way for selecting control rules and the number of control measurements needed to detect medically important errors. The concept of a quality control plan is described, along with alternative adaptations of a total quality control plan and a risk-based individualized quality control plan. Finally, the ongoing monitoring of analytic performance and test quality are discussed, including determination of measurement uncertainty from statistical quality control data collected under intermediate precision conditions and bias determined from proficiency testing/external quality assessment surveys. A new graphical tool, called the Sigma Quality Assessment Chart, is recommended for demonstrating the quality of current examination procedures on the sigma scale.
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The TE estimated from singleton measurements of control samples has been found to be appropriate for regulatory purposes and an extensive theoretic and practical framework has been developed around its use.
“The TE estimated from singleton measurements of control samples has been found to be appropriate for regulatory purposes and an extensive theoretic and practical framework has been developed around its use.20,22”
From Uncertainty in Measurement and Total Error (2017) · cites this paper as [22]
Error approaches, including frequentist statistics, are widely used for quality control in laboratory medicine.
“Error approaches, including frequentist statistics, are widely used for quality control in laboratory medicine.20,22,73,74”
From Uncertainty in Measurement and Total Error (2017) · cites this paper as [22]
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“The TE estimated from singleton measurements of control samples has been found to be appropriate for regulatory purposes and an extensive theoretic and practical framework has been developed around its use.(20,22)”
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- Authors
- Westgard, J. O., & Westgard, S. A.
- Affiliations
- Westgard QC Inc., Madison, WI, USA
- Corresponding author
- Westgard, James O
- Venue
- Annals of Clinical Biochemistry International Journal of Laboratory Medicine
- Publisher
- SAGE Publications
- Published
- 2015-07-06
- Volume
- 53
- Issue
- 1
- Pages
- 32-50
- ISSN
- 0004-5632 (ISSN-L)
- 1758-1001
- OpenAlex
- W2210074343
- Cited by
- 109
- References
- 45
- Citations by year
- 2026: 7 · 2025: 15 · 2024: 12 · 2023: 14 · 2022: 3 · 2021: 18 · 2020: 6 · 2019: 7 · 2018: 10 · 2017: 8 · 2016: 8 · 2015: 1
- FWCI
- 1.10
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Annals of Clinical Biochemistry International Journal of Laboratory Medicine (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Physiology › Clinical Laboratory Practices and Quality Control
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Scientific Measurement and Uncertainty Evaluation
- Health Sciences › Health Professions › Health Information Management › Healthcare Quality and Management
- Keywords
- statistical quality control, quality management systems, sigma metrics, method validation, control rules, quality control plan, measurement uncertainty, intermediate precision, bias, proficiency testing, external quality assessment
- MeSH terms
- Humans, Quality Assurance, Health Care, Statistics as Topic, Clinical Laboratory Techniques
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