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.
Introduction
Psychedelic substances such as psilocybin, LSD and DMT have been researched for their potential therapeutic effectiveness in treatment of various mental health conditions since the early 1940's. However, due to stricter political regulations, controversies regarding recreational use in the 60's subculture and methodological issues, clinical research interest slowed down after the early 1970s (Haave & Pedersen, 2021). For the past 20 years, there has been renewed interest in studying the neurobiological and therapeutic effects of these drugs, with twenty modern clinical trials using classic psychedelic drugs published since 2006. This includes trials of psychedelics for treatment of moderate-severe depression (Carhart-Harris et al., 2018; Carhart-Harris et al., 2021; Davis et al., 2021; Goodwin et al., 2022; Goodwin et al., 2023; Palhano-Fontes et al., 2019; Raison et al., 2023; Sanches et al., 2016; von Rotz et al., 2023), generalized anxiety disorder (Holze, Gasser, Müller, Dolder, & Liechti, 2023), illness related anxiety and depression (Anderson et al., 2020; Gasser et al., 2014; Griffiths et al., 2016; Grob et al., 2011; Ross et al., 2016), OCD (Moreno, Wiegand, Taitano, & Delgado, 2006), Anorexia (Peck et al., 2023) and substance use disorders (Bogenschutz et al., 2015; Bogenschutz et al., 2022; Johnson, Garcia-Romeu, Cosimano, & Griffiths, 2014). Common among most of these trials is the integration of a psychedelic drug with psychotherapy, known as psychedelic-assisted psychotherapy (Andersen, Carhart-Harris, Nutt, & Erritzoe, 2021).
Similar to psychotherapy research in general, there has been heightened interest on how psychedelic-assisted psychotherapy may alleviate psychiatric symptoms. This exploration ranges from biological research of changes in brain receptor occupancy (PET), activity (EEG), functional activity (fMRI), structural changes (CT; MRI), to psychological phenomena related to the subject's experiences of emotional breakthrough (Murphy et al., 2022), attainment of personal insights (Barba et al., 2022; Peill et al., 2022), challenging experiences, degree of ego dissolution (Barba et al., 2022) and of mystical type experiences.
The investigation of spiritual, religious and mystical experiences has a rich historical foundation in psychology, highlighted by William James' seminal work in “The Variety of Religious Experience” (James, 1902), which represents one of the earliest written inquiries into this domain. James's contribution was the idea that although religions and spiritual practices are quite varied and unique, they may still share universal «spiritual» or «religious» qualities. Walther Stace further developed James' qualitative descriptions and tried to conceptually define what common factors constitute a spiritual experience (Stace, 1960). Building on Stace's model, the Harvard researcher Walther Phanke developed the 43-item Mystical Experience Questionnaire (MEQ43) to assess the self-reported degree of mystical type experience occasioned by the ingestion of psilocybin (Pahnke, 1966). The MEQ43 has been further expanded into the States of Consciousness Questionnaire (SOCQ), in which 57 additional distractor items were added. The SOCQ has been used in studies of psilocybin in healthy volunteers and clinical populations (MacLean, Johnson, & Griffiths, 2011). The latest edition is the 30-Item Mystical Experiences Questionnaire (MEQ30) (Barrett, Johnson, & Griffiths, 2015). In the MEQ30 a mystical experience is conceptualized to consist of four distinct dimensions: 1. Mystical, 2. Positive Mood, 3. Transcendence of time and space, and 4. Ineffability.
The MEQ30 is a short and efficient assessment of mystical experiences, which may inform and help better understand the mechanism of action in psychedelic-assisted psychotherapy. The MEQ30, MEQ43 and SOCQ have all shown to be significantly correlated to treatment effects of ayahuasca (Palhano-Fontes et al., 2019) and psilocybin (Bogenschutz et al., 2015; Garcia-Romeu, Griffiths, & Johnson, 2014; Griffiths et al., 2016; Ross et al., 2016).
MEQ has in recent years been subject to translation and validation in Finnish (Kangaslampi, Hausen, & Rauteenmaa, 2020) Brazilian Portuguese (Schenberg, Tofoli, Rezinovsky, & Silveira, 2017), Japanese (Yonezawa, Tani, Nakajima, & Uchida, 2023), French (Fauvel., et al., 2023), Dutch (Wirsching, Bostoen, & Huizink, 2023) and Danish (Hovmand et al., 2024). No version yet exists in Norwegian, which calls for the translation, adaptation and validation of a Norwegian MEQ30.
This paper aims to provide researchers with a proper translated and culturally adapted version of the MEQ30 which can be used in future projects to help understand and explore mystical experiences in Norwegian populations and further facilitate cross-cultural research internationally.
Methods
Data collection
This study collected data for the pilot-testing phase using a secure online survey at the University of Oslo (Nettskjema). Since the project investigates potential sensitive data (such as illicit drug use) the project was sent in for a pre-evaluation to the Regional Committees for Medical and Health Research Ethics (REK). REK concluded that our project was not subject for further submission (ref. 197371). The Norwegian Centre for Research Data approved our plan for data collection and storage April 2022 (ref. 701009).
Translation
To ensure a systematic and culturally valid adaptation of the MEQ30, this project followed “Principles of Good Practice for the Translation and Cultural Adaptation Process for PRO Measures: Report of the ISPOR Task Force for Translation and Cultural Adaptation” (Wild et al., 2005). Specifically, we followed the following seven steps:
Forward translation. Translation of the original instrument into the target language (Norwegian). This was conducted by first (K.A) and second author (B.H). K.A and B.H are both Norwegian psychologists with research experience on the topic of altered states of consciousness and psychedelics. This step resulted in two temporary independent Norwegian versions (T0.1 and T0.2)
Reconciliation. Comparison and merging of the two Norwegian versions of the instrument. This was done to reduce risk of the translator's personal speech style or misinterpretations remaining in the translated version. This resulted in a consensus on a first Norwegian version (T1).
Back translation of the Norwegian version. Back translation was performed by an American medical doctor fluent in both Norwegian and English. This resulted in the back-translated version (BT)
Back translation review. First and second author then compared the original MEQ30 with our BT. This was done to ensure conceptual equivalence of the translated (T1) version.
Cognitive debriefing. To assess the level of comprehensibility and cognitive equivalence of our translation we tested T1 on two different samples. First an online pilot test on adult anonymous psychedelic users (n = 6) who were native in Norwegian and had at least one experience with a serotonergic psychedelic drug to collect qualitative feedback on the questionnaire's instructions, main items and on the response items. Then T1 was presented to an expert group for panel discussion. The panel consisted of six participants: four psychologists (including first and second author), one social anthropologist and one medical doctor. All with in depth knowledge regarding scientific research on psychedelics and their subjective effects. Since the first and second author were present in the panel discussion, there is a risk of their presence influencing the outcome from the panel. To limit this impact the team had a heightened focus on developing an open group culture to ensure that the participants experienced us as needing and appreciating their time and comments. We highly encouraged critical evaluations of chosen formulations and asked participants to consider alternatives whenever they felt it would be an improvement. In addition to this the panel participants were asked to read and takes note of the instruments individually for 1 h before we revised them for a lengthy panel discussion in the group. During the panel discussion we refrained from voicing personal opinions and preferences in order to limit the influence of our presence.
Review of Cognitive Debriefing Results and Finalization. First and second author then reviewed and incorporated results from the pilot-test and the expert panel, to improve the performance of the first version (T1) translation. This process led to an updated and final version of the Norwegian translation (T2), see Supplementary materials for final formatted version of T2.
Results
The translation procedure (Fig. 1) resulted in a final Norwegian version of the MEQ30 (T2), see the Supplementary materials. All three versions (T1, T2 and BT) can be found in the Supplementary materials. There were differences in item 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 15, 19, 20, 21, 23, 24, 25, 26, 27, 28, between the original MEQ30 and our BT version. The changes to these 17 items were however minor, for instance the original MEQ30 included the use of the word “sense”, and in our BT version this was translated to “experience” as can be reflected in item 7 and 13. After a thorough evaluation of each item (Table S1 in Supplementary materials) we deemed the minor grammatical changes in our BT as insignificant in relation to the conceptual meaning of each item wording. We therefore kept the T1 and provided no changes at this process. Following pilot-testing and feedback at debriefing we made updates on seven items of the T1 version, creating T2. The updated items are: 4, 7, 12, 25, 27, 29, 30. Specific changes for each item from T1 to T2 are documented in Table S2 in Supplementary materials. These were minor changes mostly related to adapting them for intuitive Norwegian understanding, changing sentence structure and word endings. However, the American word «awe» became an important aspect for in-depth discussions, as no such direct translation exists in Norwegian. Suggestions for Norwegian translations were «Ærbødighet», «Ærefrykt» and «Aktelse». The Oxford Advanced American English Dictionary describes awe as «Feelings of respect and slight fear; feelings of being very impressed by something or someone». Following this, the group decided on the use of «Ærefrykt» as an adequate Norwegian translation of «Awe», as it ensures conceptual equivalency. For the word “reverence” a similar discussion followed, here we choose the Norwegian equivalent “Ærbødighet”. Interestingly, following the translation process of our version, the Danish MEQ30 was published (Hovmand et al., 2024). Norway and Denmark are quite similar in terms of culture and language, and in examining items containing the word “Awe” (item 27) and “Reverence” (item 21) we discovered that in Danish it was translated with “ærefrygt” and “ærbødighed” which is equivalent to the Norwegian word “ærefrykt” and “ærbødighet”. This further validates and supports our conceptual equivalency and validation of the translation process.
Flowchart of translation process
Citation: Journal of Psychedelic Studies 9, 1; 10.1556/2054.2024.00346
Discussion
To further develop and prepare for Norwegian research into psychedelic assisted psychotherapy and psychedelic neuroscience, a rigorous Norwegian adaptation of the MEQ30 was a small but crucial project. The next step of importance is providing a good assessment of its psychometric validity and reliability when assessing Norwegian populations. The English version of the MEQ30 shows strong internal consistency (Cronbach's alpha) on MEQ total score (0.800), mystical (0.933), positive mood (0.926), time/space (0.831) and ineffability (0.810). Similar internal consistencies, as well as predictive and discriminant properties are also seen for the French, Finnish, Dutch, and Brazilian Portuguese versions (Fauvel., et al., 2023; Kangaslampi et al., 2020; Schenberg et al., 2017; Wirsching et al., 2023). Interestingly, in the French, Finnish, and Brazilian Portuguese translations the factor of “Positive mood” has a lower internal consistency than the original. Recent studies have critiqued the MEQ30 instrument for including this factor as part of the mystical experience, as it may conflate the concepts of positive emotion and mystical experience, thus overlooking negative mystical experiences (Oliver, 2023). We hope future psychometric validations of MEQ may further investigate and potentially update or revise the model. In line with upcoming surveys and research projects on psychedelic use in Norwegian we hope to be able to collect sufficient data which will allow us to also provide an updated psychometric validation of the Norwegian version presented in this paper. An online survey on a Norwegian psychedelic user sample was recently completed (Kvam et al., 2013), providing data for an upcoming psychometric validation of Norwegian versions of the Challenging Experience Questionnaire and the Emotional Breakthrough Inventory.
Currently, this version of the Norwegian MEQ30 will be included as a measure of a potential underlying mechanism of action in an upcoming trial of ketamine for combined depression and alcohol use disorder: A Randomized rater-blinded controlled trial (Blomkvist, Grønli, & Andreassen, 2023). We hope that the Norwegian MEQ30 will serve as a valuable instrument for other psychedelic research projects as well. We believe it can be a valuable tool for exploring the relationship between psychedelics' subjective effects, underlying brain activity and possible clinical outcomes in treatment trials. Additionally, researchers in adjacent fields studying phenomena such religion, meditation, near-death experiences, or the like, might also find this questionnaire useful.
In conclusion we have developed the first Norwegian translation of the MEQ30, which provides researchers the possibility to assess an important experiential factor critical to international psychedelic research trials in both clinical and healthy volunteers.
Limitations
We did not collect information regarding the pilot-testing group demographics, therefore we cannot be certain of how well they represent the typical norwegian psychedelic user. Due to us not collecting data on the survey itself, its psychometric properties remains unknown.
Conflict of interest
None of the authors have any affiliations that could be considered a financial conflict of interest. Main Author K.A works as a PhD student at Oslo University Hospital. Second author B.H works a psychologist at Oslo University Hospital. Both K.A. and B.H works part-time as a psychologist for Psykolyse, a private practice that offer courses for healthcare professionals on psychedelic research, and provide harm-reduction psychotherapy to psychedelic users. Last author L.H.S owns and runs a private ketamine clinic (Axonklinikken) in Norway. He also works part-time as a medical doctor at Sykehuset Østfold, Norway. We received no funding or other support for the work on this manuscript.
Acknowledgments
The authors would like to thank Henrik Børsting Jacobsen for assisting authors with setting up the questionnaire at Nettskjema and seeking approval for the study. We owe a debt of gratitude to the anonymous psychedelic users participating in the online-pilot test and the following professionals for their invaluable input in commenting and discussing the appropriateness of our translation: Camilla Øyhus, Anna Høifødt, Øystein Nødtvedt, Ian Arne Sørhhagen, and Ingrid Autran.
Supplementary materials
Supplementary data to this article can be found online at https://doi.org/10.1556/2054.2024.00346.
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