Unit 1528: Laboratory Quality Control

1. Introduction to Laboratory Quality Control

• Definition and purpose of quality control (QC) in laboratories
• Importance of QC in ensuring accurate and reliable test results
• Key principles and concepts of laboratory QC:
  • Accuracy, precision, reliability
  • Error types: systematic vs random
  • Quality assurance vs quality control

2. Quality Control Materials and Procedures

• Types of QC materials:
  • Controls (normal, abnormal, and critical)
  • Calibrators and standards
• Selection criteria for QC materials
• Storage, handling, and maintenance of QC materials
• QC procedures:
  • Preparation and use of controls
  • Frequency of QC testing
  • Documentation of QC activities

3. Statistical Concepts in Quality Control

• Basic statistical measures:
  • Mean (average)
  • Standard deviation (SD)
  • Range
• Control limits:
  • Calculation of upper and lower control limits (UCL, LCL)
• Interpretation of QC data using statistics
• Understanding variability and its impact on test performance

4. Quality Control Charts

• Purpose of QC charts in monitoring test performance
• Levey-Jennings charts:
  • Structure and components
  • Plotting QC data
• Westgard rules:
  • Explanation of individual rules (e.g., 1 2s, 2 2s, R 4s, 4 1s, 10 x)
  • Application of Westgard rules to detect errors
• Using charts to identify trends, shifts, and outliers

5. Troubleshooting Quality Control Issues

• Common QC problems:
  • Shifts in control values
  • Trends over time
  • Outliers and random errors
• Systematic vs random error identification
• Root cause analysis techniques
• Corrective actions and preventive measures

6. Quality Control Documentation and Record-Keeping

• Importance of documentation in QC
• Types of QC records:
  • Control charts
  • QC logs and worksheets
  • Maintenance and calibration records
• Frequency and standards for documentation
• Regulatory and accreditation requirements (e.g., ISO 15189)

7. Quality Control Audits and External Quality Assessment

• Internal QC audits:
  • Purpose and scope
  • Audit procedures and checklists
  • Reporting and follow-up actions
• External quality assessment (EQA) programs:
  • Overview and objectives
  • Participation and sample testing
  • Performance evaluation and benchmarking
• Integrating audit and EQA findings into QC improvements