LabQMHub Editorial Team · ISO 15189:2022 Quality Management Series
How does a laboratory know its quality management system is actually working, rather than simply assuming it is because procedures exist on paper? ISO 15189:2022’s Clause 8.8 answers this through three complementary evaluation mechanisms: continuous quality indicator monitoring, periodic internal audits, and external accreditation assessment — each answering the same underlying question from a different vantage point.
This evaluation trio forms the laboratory’s genuine feedback loop, and understanding how the three mechanisms work together, rather than in isolation, is essential to building an evaluation program that provides real, not merely superficial, assurance.
Quality Indicators: Continuous, Objective Performance Monitoring
Quality indicators track laboratory performance numerically and continuously across the pre-examination, examination, and post-examination phases — specimen rejection rate, turnaround time, critical value notification time, and dozens of other measurable dimensions — providing an ongoing pulse check that complements the point-in-time findings of an audit.
Meaningful indicator targets are grounded in historical performance, clinical impact, and benchmarking, not arbitrary round numbers, and require a genuine, predefined action plan for what happens when an indicator misses its target — an indicator tracked but never acted upon provides no real value beyond the appearance of monitoring.
Internal Audits: Periodic, Risk-Based Self-Examination
Internal audits provide planned, systematic confirmation that the management system conforms to both the laboratory’s own requirements and those of ISO 15189:2022, and is effectively implemented in daily practice, not merely documented in theory. A risk-based audit schedule — auditing higher-risk areas more frequently than lower-risk ones — makes better use of limited audit resources than a uniform, calendar-driven rotation applied regardless of actual risk.
Effective audits combine multiple evidence-gathering techniques — interviewing staff, directly observing actual practice, and reviewing records — since relying on any single technique alone risks missing exactly the kind of gap between documented procedure and actual practice that audits exist to uncover.
From Finding to Verified Closure
An audit finding is not complete once identified and reported — it must follow the same corrective action discipline covered in the previous course of this program, including root-cause investigation, proportionate action, and verified effectiveness, before the finding can genuinely be considered closed.
Tracking findings to true closure, not merely to the point where some action was taken, is what separates a genuinely functioning internal audit program from one that generates reports without producing lasting improvement — a distinction assessors specifically look for during accreditation surveillance visits.
Accreditation: The External, Independent Confirmation
Accreditation combines document review with witnessed assessment of actual laboratory practice, providing external, independent confirmation that complements a laboratory’s own internal quality indicator and audit programs, rather than replacing the need for them. A laboratory with genuinely functioning internal evaluation activities is substantially better prepared for accreditation than one scrambling to demonstrate compliance only in the weeks before an assessment visit.
Maintaining accreditation is an ongoing discipline, not a one-time achievement — a laboratory should continue its full quality indicator monitoring and internal audit programs between accreditation cycles exactly as it did before achieving accreditation, treating the accreditation as confirmation of existing discipline rather than a finish line.
Frequently Asked Questions
What is the difference between a quality indicator and an internal audit?
A quality indicator provides continuous, numeric monitoring of performance over time; an internal audit provides a planned, periodic, point-in-time examination of whether a defined scope conforms to requirements.
Why should internal audits be risk-based rather than a fixed rotation?
Because it makes better use of limited audit resources, ensuring higher-risk areas receive more frequent scrutiny than lower-risk areas, rather than treating every area identically regardless of actual risk.
Does achieving accreditation mean a laboratory can relax its internal evaluation activities?
No — accreditation should be maintained through continued, ongoing quality indicator monitoring and internal audits, treated as confirmation of existing discipline rather than a finish line.
Key Takeaways
- Quality indicators, internal audits, and accreditation together form the laboratory’s feedback loop, each answering the same question from a different vantage point.
- Quality indicators provide continuous, numeric monitoring that complements the point-in-time findings of an audit.
- A risk-based internal audit schedule makes better use of limited resources than a uniform, calendar-driven rotation.
- Effective audits combine interview, observation, and record review, since no single evidence-gathering technique alone is sufficient.
- Audit findings must be tracked through corrective action to verified closure, not merely to the point an action was taken.
- Accreditation is maintained through ongoing internal evaluation discipline, not treated as a one-time achievement.
Conclusion
Genuine self-knowledge is difficult for any organization, and laboratories are no exception — without deliberate, structured evaluation mechanisms, a laboratory can easily mistake the existence of procedures for the reality of consistent, effective practice.
ISO 15189:2022’s evaluation requirements ensure this self-knowledge is built systematically, combining continuous monitoring, periodic self-examination, and independent external confirmation into one coherent, ongoing discipline.
Complete your ISO 15189:2022 learning journey with the final course in this series, covering management review and how it closes the entire quality management system cycle.
Source note: this article draws on “Quality Management in Clinical Laboratory Demystified” by Dr. Taleb Chalab Cham, ISO 15189:2022, and widely recognized clinical laboratory quality references including CLSI guidelines, CAP accreditation checklists, and WHO laboratory quality guidance.
