Cross-section

Sermorelin 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 Sermorelin, with a class minimum gradient of 15 min, the method is a live explanation.

96 recordsmedian 98.94 %spec 98.0 %

Laboratory	Reports	Gradient	MS resolution	Median purity %	Published bias (pp)	Bias-adjusted	Method suitability
Janoshik	39	30min	High	99.05	+0.00	99.05	ADEQUATE
Medutest	24	25min	Unit	98.99	+0.08	98.91	ADEQUATE
PeptideMeter	14	28min	High	98.92	-0.05	98.97	ADEQUATE
Nordanalyt	9	35min	High	98.71	+0.02	98.69	ADEQUATE
VendorInvestigate	5 n=5	32min	High	98.47	-0.11	98.58	ADEQUATE
Kestrel	5 n=5	15min	Unit	98.94	+0.24	98.70	ADEQUATE

Figure. Sermorelin 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.