Verification samples were obtained from Luminex‘s xTAG Gastrointestinal Pathogen Panel (xTAG GPP). Verification samples contained real or synthetic stool samples with live or recombinant material, with some specimens being positive for more than one clinical target. A total of 40 positive control samples were used, 35 of which were certified to be positive for one control taxon from our target list, with the exception of those samples containing either Clostridium difficile or Salmonella enterica which are positive for 2 taxa simultaneously (the species to which they belong and their corresponding genus). The control samples were considered negative for the remainder of the taxa on our test panel. Two out of 35 control samples did not pass our sequencing quality thresholds of having at least 10,000 pair-end reads each, so they were removed from further analysis. Five additional Luminex samples positive for Yersinia, a genus that is not present in the final target list, were included as negative controls. Verification samples were processed in uBiome microbiome sampling kits using the clinical pipeline described above.