Objective: To investigate the reliability and validity of the Korean version of the Community Assessment of Psychic Experiences-15 item positive scale (CAPE-15) in college students.
Methods: This study had two stages: initial screening with self-report questionnaires including the CAPE-15, and semi-structured interviews to investigate the instrument's diagnostic validity. The initial screening involved 1,749 college students. The modified Korean version of Prodromal Questionnaire-16 item (mKPQ-16) was also administered. The criteria for ultra-high risk (UHR) of psychosis in the Comprehensive Assessment of At-Risk Mental States (CAARMS) were the gold standard for diagnosis.
Results: Twelve of the interviewed subjects met the CAARMS criteria for UHR of psychosis. The area under the receiver operating characteristic curve was highest (0.936) for the CAPE-15 distress score (p<0.001). The use of 6 as the cutoff for the CAPE-15 distress score resulted in the best balance of sensitivity (91.7%) and specificity (85.2%), with a favorable positive predictive value of 32.4%. The coefficients of correlation between the CAPE-15 and mKPQ-16 were significant.
Conclusion: The Korean version of the CAPE-15 is a good instrument for screening for psychosis risk in collegiate settings. The validation of this scale could contribute to the early identification of psychosis in the Korean community.
Keywords: Attenuated psychosis syndrome; CAPE-15; Prodrome; Schizophrenia; Ultra-high risk.