“…43,45 In the remaining five studies, the POCUS operator was an ED doctor. 13,34,42,44,46 Of the seven studies, four reported the accuracy of a mixture of secondary signs. 11,42,43,46 The reference standards used included surgical and pathology reports in two studies, 11,46 pathology report in one study, 45 discharge diagnosis in two studies, 42,44 a combination of pathology report and discharge diagnosis in one study 43 and clinical follow-up in one study.…”