Fig. (4) Comparison of the ROC curves between the PQ-B frequency score and the PQ-B distress score against the target, i.e., high at-risk mental states (HARMS) cases as defined on the basis of the validated GHQ-12 and SPQ thresholds. The statistical significance of the difference between the areas under the two dependent ROC curves (derived from the same cases) with the method of DeLong et al. [58] is reported.