When a point-of-care device is compared to a core laboratory analyzer, we assume the core laboratory analyzer is always "right". But what if we can't tell whether either the point-of-care method or the core lab method is correct? When methodology is not the same, how do you handle the differences and bias between devices?
Sigma Metric Analysis
A 2015 study compared the performance of two blood gas analyzers with a core laboratory instrument. Can we assume that our modern blood gas results will match the core labs results?
A 2014 article in the Nigerian Medical Journal assessed the Sigma-metrics of a chemistry analyzer. The results raise important questions.
A 2013 study from the Journal of Laboratory Medicine and Quality Assurance evaluated the performance of a Chinese manufactured automated chemistry analyzer running Korean reagent. The study produced a lot of r-values in the 0.99 range. Does this mean the analyzer-reagent combination is better than the west?
A 2014 letter to the editor of the International Journal of Laboratory Hematology evaluated the performance of the Mindray automated hematology analyzer BC 6800. The letter authors concluded this instrument is "good and precise." Does Sigma-metric analysis agree?