Measures of Psychedelic Experiences
Since initiating our research in 2000, the Center for Psychedelic and Consciousness Research has developed a variety of tools to characterize and quantitatively measure the phenomenology of psychedelic experiences. These tools have been used by researchers around the world to gain a better understanding of the effects of psychedelics and to predict clinical improvements.
Below are questionnaires developed by our team, as well as their validated translations.
Mystical Experience Questionnaire (MEQ-30, English)
The MEQ-30 is a 30-item scale where each question is answered on a 6-point scale ranging from 0-5 (none; not at all=0, so slight cannot decide=1, slight=2, moderate=3, strong=4, extreme=5). There are four subscales in this questionnaire: Mystical, Positive mood, Transcendence of time and space, and Ineffability.
Original Reference: Barrett, F. S., Johnson, M. W., & Griffiths, R. R. (2015). Validation of the revised Mystical Experience Questionnaire in experimental sessions with psilocybin. Journal of Psychopharmacology, 29(11), 1182–1190. doi: 10.1177/0269881115609019
Translations
Spanish, full version (30-items): View manuscript | Download measure
French, full version (30-items): View manuscript | Download measure
Brazilian Portuguese, full version (30-items): View manuscript
German, full version (30-items): View manuscript | Download measure
Japanese, full version (30-items): View manuscript | Download measure
English, short version (4-item): View manuscript | Download measure
Challenging Experience Questionnaire (CEQ-26, English)
The Challenging Experience Questionnaire is a 26-item questionnaire. Responses are given on a 6-point scale (None; not at all = 0, so slight cannot decide = 1, slight = 2, moderate = 3, strong = 4, extreme; more than ever before in my life = 5). There are 7 subscales in this questionnaire. The subscales are as follows: Fear, Grief, Physical Distress, Insanity, Isolation, Death, Paranoia
Original Reference: Barrett, F. S., Bradstreet, M. P., Leoutsakos, J. S., Johnson, M. W., & Griffiths, R. R. (2016). The Challenging Experience Questionnaire: Characterization of challenging experiences with psilocybin mushrooms. Journal of Psychopharmacology, 30(12), 1279- 1295. doi:10.1177/0269881116678781
Translations
Spanish, full version (26-items): View manuscript | Download measure
German, full version (26-items): View manuscript | Download measure
Japanese, full version (26-items): View manuscript | Download measure
English, short version (7-item): View manuscript | Download measure
Psychological Insight Questionnaire (PIQ-23, English)
The Psychological Insight Questionnaire (PIQ; Davis et al., 2021) measures acute psychologically insightful experiences that may occur during psychedelic experiences. The PIQ was created to assess the intensity with which respondents experienced a broad range of acute insight after taking a classic psychedelic.
Original Reference: Davis, A.K., Barrett, F.S., So, S., Gukasyan, N., Swift, T.C., & Griffiths, R.R. (2020). Development of the Psychological Insight Questionnaire among a sample of people who have consumed psilocybin or LSD. Journal of Psychopharmacology, 35(4), 353-361.
Translations
Spanish, full version (27-items): View manuscript | Download measure