Lesson 12, QC Planning for Healthcare Laboratories, WesTgard ® Quality Corporation © 1997

Lesson 12: Applications - How do you assess the performance of a recommended QC procedure?

In The Myth of Medical Decision Limits, the practice of using clinical and fixed control limits is evaluated. The QC planning process is used to first figure out what the actual statistical control rule is, then to evaluate that rule's performance based on its error detection and false rejection characteristics. A Glucose Point-of-Care application illustrates the proper approach for designing a QC procedure on the basis of a defined clinical quality requirement.

View the Outline View the Syllabus View the Archives View the Reference List View the Glossary

Objectives:

Learn how to evaluate QC recommendations.
Understand the difference between a clinical control limit and a clinical quality requirement.
Review how to use clinical quality requirements for selecting QC procedures.

Web materials:

Essay: The Myth of Medical Decision Limits
QC planning application: Glucose point-of-care method

Things to do:

Study the materials.
Find out if there are any applications of clinical or fixed control limits in your laboratory.
For an example of non-statistical control limits, make an assessment of the expected performance of the QC procedure.

Assessment: View the Answers

A manufacturer recommends that control limits be set as the mean +/- 8% of the expected bottle value for a POC glucose method. If you wanted to satisfy the CLIA criterion for acceptable performance and were to make 2 control measurement in a run with a method having a CV of 2.0%, would the manufacturer's recommended control limits provide appropriate error detection? Assume a decision level of 100 mg/dL.

Return to the top
View the Participant Q & A

Questions, comments, suggestions, and feedback are encouraged! Use feedback form on this website Or e-mail westgard@westgard.com.

This website is best viewed by Internet Explorer or Netscape 2.0 or better.