Sigma Metric Analysis
Recently, with the help of some Chinese laboratorians, we translated the studies of Sigma-metrics of several chemistry instruments.
Back in 2011, we took a look at the Olympus AU 2700 plus. In 2016, it's time to take a look at the more recent models, like the Olympus AU 5800.
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?
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?
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.