Fig. 5.

The reproducibility of univariate statistical testing between each pair of tissue type was investigated by comparing the percentage of significant m/z species found for each center (only centers with a minimum of three experiments were considered) and the overlap between centers (green and orange bars) (a). The summary in b shows that peptide and metabolite data were overall equally discriminative, but the metabolite data was more reproducible. The meta-analysis results per tissue type comparison are shown in c. Especially the peptide data benefitted from the combination of cross-center effects, since it could assemble the samples from four centers (b, d)