Course Outline
Click on the links below to preview selected pages from this course.
- Definition of Quality Control
- Important Concepts in Quality Control
- Controls
- What is a Control?
- Safety and Handling of Controls
- Appearance of Controls
- Why Run Controls?
- Assayed and Unassayed Controls
- What is an unassayed control?
- Controls are tested (run) for all of the following reasons, except:
- Precision and Accuracy
- Aiming for the Target
- Closer, but not Quite
- Bullseye!
- An assayed glucose control produces the following results through 10 runs: 99, 99, 99, 98, 98, 98, 98, 97, 97, 97. The established range for this cont...
- Specificity
- Sensitivity
- Calculating Sensitivity
- Sensitivity Example: Calculations (1)
- Sensitivity Example: Calculations (2)
- Sensitivity Example: Comparison
- Using the data and formula to the right, we can calculate sensitivity of the West Nile Virus test to be:
- Specificity versus Sensitivity
- Sensitivity is the ability of a test to correctly identify individuals who indeed do have a particular disease or disorder. A test with high sensitivi...
- Predictive Value
- A Word on Positive and Negative Predictive Values
- How do predictive values relate to the prevalence of a disease?
- Random and Systematic Error
- Types of Error
- Random Error
- Systematic Error
- Indicate which of the factors in the list below are more likely to be random errors or systematic errors.
- Internal and External Quality Control
- Reference Ranges and X-barM
- Quality Control Procedures, Documentation and Interpretation
- Basic Terms
- Levey-Jennings Chart
- Levey-Jennings Control Charts
- What is a Levey-Jennings Chart?
- On which day(s) did the control data fall at least one standard deviation (SD) from the mean?
- Westgard Rules
- Using Westgard Rules
- Westgard Rule 13S
- Westgard Rule 22S
- Westgard Rule 41s
- Westgard Rule R4s
- The Levey-Jennings charts on the right represent two levels of control for an analyte. Do they show acceptable quality control results?
- Does the Levey-Jennings chart to the right show acceptable quality control results?
- Trends
- Shifts
- Cumulative Summation Limit (CUSUM)
- What is a Cumulative Summation Limit?
- CUSUM Example: Plotting Control Data
- CUSUM Example: Calculating CUSUM
- CUSUM Example: Exceeding the CUSUM Limit
- CUSUM and Westgard Rules
- Youden Plot
- What is a Youden Plot?
- Using a Youden Plot
- In the accompanying Youden plot, what conclusions can be drawn about the data?
- Systematic Troubleshooting
- Establishment of Verification of Method Performance Specifications
- Summary
- References
Additional Information
Level of Instruction: Intermediate
Intended Audience: Medical Laboratory Scientists, Medical Laboratory Technicians, and medical laboratory students.
Author Information: Garland E. Pendergraph, PhD, JD, MLS(ASCP)SM, HCLD/CC(ABB) is a former Laboratory Director & Director of Laboratory Operations, Quest Diagnostics-Valdosta RRL. Dr. Pendergraph received his MSPH from the University of Kentucky in Lexington, his PhD in medical parasitology and mycology from the University of North Carolina in Chapel Hill, and his law degree with a concentration in health care law from Concord Law School, Kaplan University. He also did a Fellowship in Tropical Medicine at Louisiana State University School of Medicine. He is the author of a textbook on phlebotomy, several scientific articles, plus internet training programs.
Reviewer Information: Dr. Julie Ann West is certified by the American Society for Clinical Pathology (ASCP) as a Medical Laboratory Scientist (MLS) and as a Specialist in Microbiology (SM). In addition, Dr. West has earned a PhD in Public Health - Infectious Disease Epidemiology - and is Certified in Public Health (CPH) by the National Board of Public Health Examiners. Dr. West is experienced as a Technical Specialist, Safety Officer, Educator, and Lead in the Veterans Administration Healthcare System, and has prior experience as an Administrative Laboratory Director.
Scope: Basic medical laboratory quality control is discussed in this course.
