Assessment of psychedelic--induced states: Norwegian translation and adaptation of the revised Mystical Experience Questionnaire (MEQ-30)

Abstract Background Previous international clinical trials have indicated that mystical experiences resulting from the consumption of classic psychedelic drugs, such as psilocybin, may represent a subjective psychological mechanism of action associated with therapeutic effects for various mental disorders. The revised 30-item Mystical Experience Questionnaire is one of several psychometric scales designed to evaluate such subjective experiences induced by psychedelic drugs. The field of psychedelic research is growing in Scandinavian countries, yet there is currently a lack of translated and culturally adapted Norwegian versions of rating scales for assessing psychedelic drug-induced states of consciousness. With planned and upcoming psychedelic research projects in Norway, there is a need for a Norwegian version of the MEQ30. Aims We aimed to translate and adapt the Revised Mystical Experiences Questionnaire (MEQ30) from English to Norwegian. Methods We used rigorous translation methods, including two independent forward translations, one back-translation, pilot testing on a small psychedelic user group ( n = 6) and cognitive debriefing in an expert-panel ( n = 6) to ensure a culturally adapted Norwegian translation. Results Our translation and adaptation procedure resulted in a final Norwegian version of the MEQ30. Conclusion The Norwegian MEQ30 is ready to be implemented in future Norwegian trials. Its psychometric properties have not yet been assessed.