Aim: The aim of this study was to examine the reliability, validity, sensitivity and specificity of the Chinese version of the 16-item Prodromal Questionnaire (CPQ-16) for identifying attenuated psychosis syndrome (APS) in a college population.
Methods: The participants were recruited from a university. Five hundred seventy-nine students completed the CPQ-16 and the Symptom Checklist-90. One class (n = 79) was randomly selected to be retested with the CPQ-16 after 2 weeks. A randomly selected group of 49 individuals who tested positive and 50 individuals who tested negative were interviewed using the Structured Interview for Prodromal Syndromes (SIPS).
Results: The internal consistency reliability was good (Cronbach's α = 0.72). The test-retest reliability was 0.88. The total score on the CPQ-16 was moderately to highly correlated with the total score on the Symptom Checklist-90 and all of the subscales (r = 0.39-0.67, P < 0.001). A cut-off CPQ-16 score of 9 was used to differentiate between those with a APS diagnosis on the SIPS versus those with no SIPS diagnoses; this cut-off value yielded 85% sensitivity, 87% specificity, a positive predictive value of 63% and a positive likelihood ratio of 6.69. The area under the ROC curve (AUC) was significant for the CPQ-16 total score (AUC = 0.93, SE = 0.026, 95% CI = 0.87-0.98, P < 0.001). Based on the proposed cut-off score, the CPQ-16 yielded a positive rate of 5.0% (29/579).
Conclusions: The CPQ-16, administered in a face-to-face interview, demonstrated high reliability and the ability to identify college students at risk for psychosis.
Keywords: China; Chinese version of the 16-item Prodromal Questionnaire (CPQ-16); attenuated psychosis syndrome.
© 2014 Wiley Publishing Asia Pty Ltd.