493.1281—Standard: Comparison of test results.
(a)
If a laboratory performs the same test using different methodologies or instruments, or performs the same test at multiple testing sites, the laboratory must have a system that twice a year evaluates and defines the relationship between test results using the different methodologies, instruments, or testing sites.
(b)
The laboratory must have a system to identify and assess patient test results that appear inconsistent with the following relevant criteria, when available:
(3)
Diagnosis or pertinent clinical data.
(4)
Distribution of patient test results.
(5)
Relationship with other test parameters.
(c)
The laboratory must document all test result comparison activities.