<qa>  What is the purpose of this study?The objective of this study is to establish the diagnostic accuracy of xTAG GPP through a multi-site, method comparison study on prospectively collected, left-over, and anonymized stool specimens. The prospective sample set will also be supplemented with pre-selected archived left-over specimens for low prevalence targets only. Diagnostic accuracy will be expressed in terms of clinical sensitivity and specificity for each target. 