Fig. 1. Ability of laboratories to detect MR^4.5.

Overall laboratory scores per reference gene were defined as green (detects MR^4.5 in a high proportion of samples, combined score > 80%), amber (detects MR^4.5 in most samples, combined score > 60%) or red (unable to detect MR^4.5 in most samples, combined score < 60%). The bar charts show the number of data sets in each category for all laboratories. Several laboratories submitted data for more than one reference gene or assay and therefore the number of data sets analysed is greater than the number of participating laboratories.