The third edition incorporates data from three CAP surveys, with the survey conducted in the fall of 2001 leading to the addition of 27 new “exempt media.”
Provides the M22-A3 PDF with Digital Rights Management (DRM) protection.
Fundamental methodology
Eliminates unnecessary, repetitive testing of highly reliable media batches, saving time, labor, and reagents. Exempt vs. Non-Exempt Media
M22-A3 distinguishes between simple linear regression (y = mx + b) and more complex weighted regression (e.g., 1/x or 1/x²). It warns that heteroscedasticity (increasing variance at high concentrations) is common in LC. The guideline provides statistical methods (e.g., lack-of-fit F-test) to verify the calibration model.
Media with a documented failure rate of are categorized as Exempt , meaning clinical laboratories are not required to perform their own routine QC testing on these products, provided certain conditions are met. Conversely, media with a failure rate greater than 0.5% are designated as Nonexempt , and user quality control is required.
For these media, the user laboratory only needs to perform a visual inspection for defects like cracking, freezing, contamination, or hemolysis. 2. Non-Exempt Media (Must be Tested by the Laboratory)
Appendix and reference material
Commercial Control Materials for Susceptibility Testing; Approved Standard—Third Edition Publisher: Clinical and Laboratory Standards Institute (CLSI) Status: Withdrawn (Superseded by CLSI M22, M23, and M100 integration)
A critical part of the document, this section outlines the responsibilities of three key parties: