Q: What if we can't Westgard Sigma Rules?

Another Question from the "Cut Your QC" webinar:

"If management is unwilling to adopt the Sigma-metric method, is there a better Westgard Rule than 1:2s to apply across the board to all analytes?"

If Westgard Sigma Rules aren't a possibility at your laboratory, there are still better ways to run QC using the 1:2s rule. Remember, with 2 controls, the 1:2s rule will generate 9% false rejection. Almost 1 of 10 runs is going to be out of control. So if your lab has you'll probably see alarms every day

If you can't - or won't - characterize the performance of the method, then applying a uniform set of modern Westgard Rules will still be an improvement over the 1:2s.

The 1:3s/2:2s/R:4s/4:1s/8:x with 2 controls, where the 1:3s/2:2s/R:4s can be interpreted in the first run (R=1), 2 runs are needed for the 4:1s interpretation, and 4 runs are needed for the 8:x interpretation. This multirule set will give about 3% false rejection, which is a 66.6% reduction from the 1:2s with 2 controls.

Even that simple step will provide significant savings, but only if you stop reacting to the 2sd outliers with repeats, recalls, etc. That may be the hardest part: getting staff that have been accustomed to repeating controls for years, even decades, to un-learn that bad habit.

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Watch the recording of Cut Your QC here: https://us02web.zoom.us/webinar/register/WN_F5IRlqySRR6eRcrm9Zz9mQ passcode: 746694

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