2.3.2. Prodromal Questionnaire (PQ-16)

The Prodromal Questionnaire (or PQ-16) [1] is a self-report questionnaire that was developed to identify psychotic vulnerability and used for psychosis risk screening. It evaluates the presence of negative and positive psychotic symptoms, considering the patient’s personal experience in the last month. The cut-off for psychotic vulnerability is a score of 6 (or more) [1]. The PQ-16 has 16 items that investigate different vulnerability aspects: nine items explore perceptual abnormalities and/or hallucinations, five items unusual thought content, delusional ideas and/or paranoia, and two items negative symptoms. For each item, the individual can indicate if they have experienced the symptom or not and then express the distress that experiencing that symptom entails, from 0 (No) to 3 (Severe). Scores of each item are added to arrive at the final score [1].