Cross-section

SLU-PP-332 by laboratory

The same compound measured by different laboratories on different gradients. Where the medians differ, the question is whether the material differed or the method did — and for SLU-PP-332, with a class minimum gradient of 15 min, the method is a live explanation.

22 recordsmedian 98.88 %spec 98.0 %

Laboratory	Reports	Gradient	MS resolution	Median purity %	Published bias (pp)	Bias-adjusted	Method suitability
Janoshik	8	30min	High	98.81	+0.00	98.81	ADEQUATE
PeptideMeter	5 n=5	28min	High	98.85	-0.05	98.90	ADEQUATE
VendorInvestigate	5 n=5	32min	High	98.97	-0.11	99.08	ADEQUATE
Medutest	2 n=2	25min	Unit	99.51, 99.20	+0.08	—	ADEQUATE
Nordanalyt	1 n=1	35min	High	98.38	+0.02	—	ADEQUATE
Kestrel	1 n=1	15min	Unit	99.04	+0.24	—	ADEQUATE

Figure. SLU-PP-332 purity by contributing laboratory. Any offset between rows has two possible sources — a real difference in the material each laboratory happened to receive, and the laboratory's own bias — and this figure cannot separate them. The paired analysis that can is on inter-lab agreement.