“…According to our own investigations, the criteria were unable to distinguish between IBS and lactose malabsorption [31]. Their sensitivity and specificity were 67% and 70%, respectively, in one study [32] and 58% and 74% in another [33], and it varied substantially between genders [34]. The population prevalence of IBS varied between 5% and 25%, depending on the different Rome IBS definitions used [19,35].…”