EP23 – Again

June 10, 2009

ep23-revThe title of EP 23 is Laboratory Quality Control Based on Risk Management. This title and hence the document makes no sense to me.

Risk management involves enumerating potential failure modes and implementing control measures for high risk failure modes. But quality control works whether one knows about failure modes or not. In fact, one of the values of quality control is precisely that one can know nothing about failure modes yet quality control will still detect failures.

Thus, Laboratory Quality Control is not Based on Risk Management would be a corrected title but also not a very good one.

There are many ways to go about setting up a quality control program – the Westgard site is a good place to start.

To illustrate things using the figure below, the outcome of a (highly abbreviated) risk management program is nevertheless an incorrect result. If QC succeeds, the incorrect result is suppressed.


Although one could talk about the total program as risk management, there is really no connection between trying to prevent or detect the many possible failure mode causes that can lead to an incorrect result and QC which detects (some) incorrect results regardless of the cause. And QC is not based on risk management.