To address this gap, we examined substance-specific screening questions and observed somewhat consistent findings across SUDs. IRT analysis revealed that severe items—such as withdrawal and time using, and to a lesser extent, giving up activities—had low sensitivity in identifying a SUD, suggesting that use of these items as brief screeners may disproportionately miss cases of SUD (false negative). For example, sensitivity for withdrawal ranged from 0.22–0.53, indicating that about 47–78% of individuals who met criteria for a SUD in this sample did not endorse withdrawal, which can be explained partly by its low prevalence (3.4–12.8%); this low rate indicated severe (more rare) items in IRT analysis. On the other hand, taking large amounts, inability to cut down, tolerance, and medical/psychological problems showed good-to-high discrimination values and clustered at the low-to-medium end of the IRT-defined SUD problems. These comparatively prevalent items demonstrated good-to-high ROC-AUC values in specifying cases of a SUD. For instance, sensitivity for taking larger amounts was 0.91 for alcohol, indicating that 91% of alcohol users with alcohol abuse or dependence responded affirmatively to this item. Given the consistency
