Laboratory Management, Quality Assurance, and Accreditation
Overview
This domain tests whether you can run a laboratory to an accreditation standard: quality control statistics, external assessment, document control, competence, risk management and continuous improvement.
Core rules
- Quality control: Levey-Jennings charts with Westgard rules. 1-3s is rejection; 2-2s is rejection; R-4s is rejection; 4-1s and 10x are rejection rules for systematic shift. Note that 1-2s is only a warning.
- Proficiency testing: external quality assessment is mandated for accredited laboratories, and unsatisfactory performance triggers root cause analysis and corrective action.
- Accreditation bodies: ISO 15189 for medical laboratories, CAP accreditation, and JCI for hospital-wide standards. Each requires documented validation of methods, equipment calibration with metrologic traceability, and periodic competency assessment.
- Risk management: failure mode and effects analysis for prospective risk, root cause analysis for incidents, and corrective and preventive action cycles.
- Preanalytical error accounts for the majority of laboratory mistakes; mislabeled specimens must be rejected, not corrected.
Worked example
A chemistry analyzer produces two consecutive control results more than 2 SD above the mean on the same level. Reasoning: this is a 2-2s violation, a rejection rule indicating systematic error, so patient results must be held and the run investigated for calibration drift, reagent lot change or deterioration. If only one result had exceeded 2 SD, that single 1-2s would be a warning requiring inspection of the next result, not automatic rejection.
Traps
Rejecting a run on a single 1-2s. Accepting a mislabeled sample after verbal confirmation. Treating proficiency testing as optional. Confusing calibration with calibration verification.