OAV and 5D-ASC for Brazilian Portuguese: A validation and adaptation study.

Background: This study aimed to validate and culturally adapt the Altered States of Consciousness Rating Scale (OAV) and Five Dimensional-Altered States of Consciousness Questionnaire (5D-ASC) for Brazilian Portuguese to measure altered states of consciousness in the context of psychedelic research.

Methods: A parallel back-translation model was employed with expert reviews to ensure linguistic and cultural accuracy. The finalized version was pre-tested with 10 participants and subsequently included in an online survey. This survey was completed by 3762 respondents recounting their psychedelic experiences. Exploratory factor analysis and confirmatory factor analysis were conducted to identify the factor structure and validate the scales. Internal consistency and convergent validity were assessed through correlation with the Mystical Experience Questionnaire (MEQ) and Ego Dissolution Inventory (EDI).

Results: The analyses confirmed an 11-factor structure for the OAV and a 6-factor structure for the 5D-ASC, both exhibiting strong internal consistency (α > 0.76). Significant correlations were observed between OAV and 5D-ASC factors and the MEQ and EDI, indicating solid convergent validity. Differences in factor scores were noted depending on the substance, setting, and meditation frequency, with higher oceanic boundlessness and anxious ego-dissolution scores for ayahuasca and dimethyltryptamine experiences.

Conclusions: The validated scales demonstrated reliable psychometric properties for the Brazilian context. The results highlight cultural aspects influencing subjective experiences with psychedelics. Limitations include sample homogeneity and potential recall bias. Future research should involve more diverse samples to confirm and extend these findings.