Development and Validation of the Momentary Assessment of Psychotic Experiences: A Self-Report Questionnaire...

Psychotic symptoms are dynamic, yet traditional assessments often measure them retrospectively, potentially missing meaningful symptom variability. Further, many measures are population-specific, limiting their use across the psychosis continuum. To address these gaps, we developed the Momentary Assessment of Psychotic Experiences (MAPE), a brief self-report questionnaire measuring in-the-moment psychosis across the continuum.

Validation included cross-sectional administration in two community samples (n = 1948) and one clinical sample with psychotic disorders (n = 73), as well as a repeated-administration design in two control samples (n = 1604). Exploratory and confirmatory factor analyses were conducted in community and control samples, while internal consistency was examined across samples. Convergent validity was tested against the Paranoia Scale, Magical Ideation Scale, Revised Hallucinations Scale, and Revised Social Anhedonia Scale. Concurrent validity in the clinical sample was evaluated using the Scales for the Assessment of Positive Symptoms and Negative Symptoms.

Analyses identified five factors: unusual thoughts and sensory experiences, paranoia, amotivation/anhedonia, social anhedonia, and negative affect. This structure showed excellent model fit and internal consistency in community/control samples, with comparable reliability in the clinical sample. MAPE subscales demonstrated moderate correlations with subclinical psychosis measures and interviewer-rated symptoms.

Findings support the MAPE as a valid and standardized measure of momentary psychotic experiences. By focusing on current state, the MAPE reduces retrospective bias and improves ecological validity. Designed for use across both subclinical and clinical populations, the MAPE also offers a unique tool for studying psychotic symptoms along the continuum.