Sigma Metric Analysis
Bias exists! And in a recent Clinical Chemistry study, the authors found unacceptably large biases in 4 out of 5 common immunoassays: cobalamin, folate, ferritin, TSH, and Free T4. Does a Sigma-metric analysis agree with this judgment?
Clinical Chemistry had a comprehensive review of the performance of routine serum cortisol assays, including performance on different patient cohorts of males, nonpregnant females, pregnant females, and those under different drug regimens. Is the analytical performance the same for all of these patients? And if not, how big are the differences and how do we finally judge the method performance? Does a Sigma-metric analysis clarify the picture at all?
Around 15 Years ago, in the Basic Planning for Quality Manual, we did some analysis of coagulation tests. It's been too long since we've examined the performance of these assays. So here we take a look at a recent publication about a Sysmex analyzer.
Completing our trilogy of Mindray hematology instruments, we go back to a 2013 study of the BC-3600. The study authors concluded this instrument's performance is "satisfactory." Does a Sigma-metric analysis agree?
We've been looking at a number of hematology instruments recently. It's time to look at one of the market-leading instruments from Sysmex.
IMPORTANT: Correction of an error in the original study has been made.