Validity and reliability of the CAPE: a self-report instrument for the measurement of psychotic experiences in the general population.
OBJECTIVE
General population longitudinal cohort studies have demonstrated the prognostic validity of self-reported psychotic experiences, but data on reliability and cross-validation with interview-based measures of these experiences are sparse. This study tested the reliability and validity of the Community Assessment of Psychic Experiences (CAPE42).


METHODS
At baseline, the CAPE42 was used to measure the subclinical psychosis phenotype in a general population sample (n = 765). At follow-up (mean interval: 7.7 months), the Structured Interview for Schizotypy, Revised (SIS-R), the Brief Psychiatric Rating Scale (BPRS), and the CAPE42 were administered (n = 510).


RESULTS
Baseline self-reported dimensions of psychosis were specifically and independently associated with their equivalent interview-based dimension at follow-up (standardized effect sizes of 0.4-0.5) and with their equivalent self-reported measure (standardized effect sizes of 0.6-0.8).


CONCLUSIONS
The results indicate that self-reported dimensions of psychotic experiences in general population samples appear to be stable, reliable and valid.
Konings
M
M
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, Maastricht, the Netherlands.
Bak
M
M
Hanssen
M
M
van Os
J
J
Krabbendam
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D010054:Brief Psychiatric Rating Scale / Q000706:statistics & numerical data; D015331:Cohort Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010552:Personality Assessment / Q000706:statistics & numerical data; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011159:Population Surveillance; D011594:Psychometrics / Q000706:statistics & numerical data; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D015203:Reproducibility of Results; D012307:Risk Factors; D012557:Schizoid Personality Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D012569:Schizotypal Personality Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics