pellicle
Professional Dingbat, Guru and Merkintologist
this is to be expected between reagents ... because the scales are often non-linear anyway.
a point I keep reminding people is that this is not a simple process such as measuring the thickness of a shim with a micrometer, its a complex plasma chemistry with many steps and "assumptions" (as I'm sure you know). From a Roche publication
worth reminding
https://practical-haemostasis.com/Miscellaneous/isi_and_inr.html
