Background: Adolescent self reported psychotic experiences are associated with mental illness and could help guide prevention strategies. The Community Assessment of Psychic Experiences (CAPE) was developed over 20 years ago. In a rapidly changing society, where new generations of adolescents are growing up in an increasingly digital world, it is crucial to ensure high reliability and validity of the questionnaire. Methods: In this observational validation study, we used unique transgenerational questionnaire and health registry data from the Norwegian Mother, Father, and Child Cohort, a population based pregnancy cohort. Adolescents, aged approximately 14 years, responded to the CAPE16 (n = 18,835) and fathers to the CAPE9 questionnaire (n = 28,793). We investigated the psychometric properties of CAPE16 through factor analyses, measurement invariance testing across biological sex, response before/ during the COVID19 pandemic, and generations (comparison with fathers), and examined associations with later psychiatric diagnoses. Outcomes: One third (33.4%) of adolescents reported lifetime psychotic experiences. We confirmed a three factor structure (paranoia, bizarre thoughts, and hallucinations) of CAPE16, and observed good scale reliability of the distress and frequency subscales (omega = .86 and .90). CAPE16 measured psychotic experiences were invariant to biological sex and pandemic status. CAPE9 was noninvariant across generations, with items related to understanding of the digital world (electrical influences) prone to bias. CAPE16 sum scores were associated with a subsequent psychiatric diagnosis, particularly psychotic disorders (frequency: OR = 2.06; 97.5% CI = 1.70 to 2.46; distress: OR = 1.93; 97.5% CI = 1.63 to 2.26). Interpretation: CAPE16 showed robust psychometric properties across sex and pandemic status, and sum scores were associated with subsequent psychiatric diagnoses, particularly psychotic disorders. These findings suggest that with certain adjustments, CAPE16 could have value as a screening tool for adolescents in the modern, digital world.

Prof. Andreassen has received speaker fees from Lundbeck, Janssen, Otsuka, and Sunovion and is a consultant to Cortechs.ai. and Precision Health. None of the remaining authors have any conflicts of interest.

This project received funding from the European Unions Horizon 2020 Research and Innovation Programme (RealMent; #964874, CoMorMent project; Grant #847776; Marie Sklodowska-Curie grant; #801133), the European Economic Area and Norway Grants (EEA-RO-NO-2018-0535) NIMH (#5T32MH020004-24), the Research Council of Norway (#223273, #271555, #273291, #273446, #274611, #324499, #336085, and #324252), the South-Eastern Norway Regional Health Authority (#2020060 and #2020022), and Kristian Gerhard Jebsen Stiftelsen (SKGJ-MED-021).

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The formation of MoBa and initial data collection were based on a license from the Norwegian Data Protection Agency and approval from the Regional Committees for Medical and Health Research Ethics. The Norwegian Health Registry Act regulates the MoBa cohort, and the Regional Committees for Medical and Health Research Ethics approved the current study (2016/1226/REK sor-ost C).

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