faq
How long does the screening and intake process take?
The screening and intake process generally takes 1-2 weeks. We recommend booking a session at least one month in advance to allow for adequate preparation.
Where do you source your psilocybin?
Our psilocybin is sourced from local, licensed manufacturers according to Oregon Health Authority regulations. It has been tested by a licensed laboratory to ensure purity and potency, and allows for precise dosing.
How is dosage determined?
We typically use a dose range of 25-40mg of psilocybin (equivalent to approximately 4-6g of dried mushrooms), inspired by modern clinical trials and scientific research studies.13 We also take into consideration your intentions, preferences, and past experience (or lack thereof) when determining dose. Individuals first take an initial dose of psilocybin, and after approximately 90 minutes, a facilitator offers an optional booster dose, which is approximately one-half of the initial dose.
The optional booster dose allows for a potential deepening of the psilocybin experience within a single session, according to an individual’s preference. Based on our experience, the optional booster dose greatly contributes towards maximizing the benefits of a single session.
Should I do a private session or group retreat?
The choice between a private or group psilocybin experience depends on your intentions, preferences, and priorities.
The main advantages of a private session are more personalized, one-on-one time with a licensed facilitator, allowing for more individualized attention and support. This includes more time to connect and build trust with your facilitator before the journey, more time to work on integration with your facilitator post-journey, and receiving your facilitator’s full and unwavering attention during the journey itself. A private session may be the better option if you expect to be working through challenging psychological and emotional material during your journey, or simply would prefer more privacy and regular support.
The advantages of a group retreat include the opportunity to connect with like-minded others, to share in the experience with a sense of community, and to take time away from your ordinary surroundings in a curated retreat setting. An Odyssey retreat includes hospitality elements (accommodations, meals, concierge services) and pre- and post-psilocybin journey group programming that a private session does not. While each participant’s psilocybin journey on a retreat is inwardly focused, sharing the retreat experience with a group can be a unique opportunity to lean into the joyous and connective aspects of psilocybin.
What's your cancellation policy?
30+ days before session date: full refund minus $600 (facilitator + processing fee)
15-29 days before session date: 50% refund
0-14 days before session date: 0% refund
Do you work with couples?
Yes, we do offer services for couples with a variety of options. Our primary offering is the private session model. Couples can either share a room and work with a single facilitator or choose to work with different facilitators in separate rooms but have their sessions on the same day. This depends on whether the couple wishes to focus on individual growth together or address relationship dynamics. We’re here to help you navigate this process and identify the best approach for you.
Additionally, many couples find attending a retreat together to be a wonderful and enriching experience.
How are private sessions scheduled?
After you connect with a licensed facilitator, if you and your facilitator agree to work together, you’ll schedule the psilocybin session at a time convenient for you.
What’s included in an Odyssey private session?
- Private psilocybin journey at a beautiful, licensed facility
- World-class screening & intake process
- Comprehensive preparation & integration program, including four hour-long preparation and integration sessions with your facilitator.
- Premier, lab tested, precisely dosed psilocybin
Are accommodations and food included for private sessions?
The hospitality elements of an Odyssey group retreat (accommodations, meals, concierge services) are not included in a private session. You’ll be responsible for your own accommodations, transport to and from the airport, and other necessities. We can help with transportation to/from the service center. During the intake process, we’ll share some helpful information around finding accommodations near the service center that match your preferences and budget.
How much does a private session cost?
Odyssey private sessions range from $3,500 - $4,500 USD, depending on the facilitator. While all of our licensed facilitators are highly vetted, rates may vary depending on a facilitator’s experience level, credentials, and specializations.
What if I don’t connect well with my facilitator?
Based on what we learn about you in the screening and intake process, we’ll do our best to match you with a licensed facilitator uniquely suited to working with you. However, if after your initial conversation you don’t feel that this facilitator is a good fit, we’ll be happy to match you with another facilitator to work with instead.
I’m ready to book a private session. What’s the next step?
If you’re ready to book, start the process by hitting the Start Journey button at the upper righthand corner of this page.
When are your next retreats?
Please see our Retreats page for upcoming retreat dates.
How long is an Odyssey retreat?
Odyssey retreats are four days / three nights.
What’s the retreat schedule?
An Odyssey retreat follows this schedule:
Day 1: Arrival & preparation
Day 2: Psilocybin experience
Day 3: Reflection
Day 4: Integration & departure
Specifics of preparation and integration activities may vary depending on the licensed facilitators leading the retreat.
How many participants attend each retreat?
Between 8-12 participants attend each retreat.
How many licensed facilitators attend each retreat?
Generally we have one licensed facilitator for every two participants for each retreat. A high facilitator:participant ratio allows for a deep level of support, even in a group setting.
What is the format of the psilocybin sessions?
In the morning of the second day of the retreat, we’ll travel as a group from the retreat center to a nearby licensed service center. The sessions are held in a spacious room, and you will be given a comfortable mattress to lay on and eye shades to wear. You’ll also be invited to bring any other items you may want to be comfortable during the journey (a journal, meaningful personal item or token, water bottle, etc.)
Odyssey’s licensed facilitators are present for the full duration of the session, and retreat guests are never left alone during their experience. If you ever need support during the journey, a facilitator will be there to help you. Facilitators take a non-directive approach, not trying to “guide” your experience but fluidly adapting to your needs as they arise.Music is played over a speaker in the room.
The playlists we use consist of mostly instrumental music and are curated to deepen and enhance the psychedelic experience. Participants are encouraged to focus on their own inner experience, and to allow others the space to do the same. We ask that participants not interact with one another during the session. Everyone is in the same physical space, having their own private journey.
This combination of laying down with music, eye shades, and focusing inward with non-directive support is the format used in psychedelic research studies at Johns Hopkins, Imperial College London, NYU, and other institutions. See our Science page for more on how Odyssey’s session format draws on scientific research protocols.
How many psilocybin sessions are there on a retreat?
Our retreats include one psilocybin session, done on the second day of the retreat.
How much does a group retreat cost?
Odyssey retreats range from $3,500 - $6,500 USD for one participant, depending on choice of accommodation. Primarily private room accommodations are available, with a few shared rooms. If you click 'Book Now' on the retreats page and continue to follow the instructions, you'll see room availability and pricing..
What’s included in an Odyssey retreat?
4-day, all-inclusive retreat
An immersive 4-day retreat at our beautiful retreat center, with each day curated to ensure you have the most transformative experience possible. All retreat costs (accommodations, meals, etc.) included.
Group psilocybin journey
Guided psilocybin journey at a licensed facility with professional facilitators.
High-quality psilocybin
Our psilocybin is sourced locally from licensed manufacturers, ensuring its quality, potency, and allowing for precise dosing.
Comprehensive preparation & integration
Engage in individual and group preparation and integration processes professionally designed to ensure you get the most out of your experience.Private chefDelicious, healthy meals by our private chef provided throughout the weekend.
Concierge services
We handle all the details, including transport to and from Redmond airport, so you’re free to focus fully on your own process.
Are flights included?
Flights are not included. If you’re traveling from out of state, you’ll need to book your own flights to and from Redmond Airport (RDM). During the intake process, we’ll let you know the best times to arrive and depart from the airport.
What accommodations are available?
If you click 'Book Now' on the retreats page and continue to follow the instructions, you'll see room availability and pricing.
Can my partner and I attend as a couple?
Absolutely! Attending a group retreat with your partner can be a wonderful way to share in the experience together. During the booking process, you can indicate that you’ll be booking for multiple people.
Can my friend, relative, or partner accompany me to the retreat, but not participate themselves?
Due to the format we follow, we’re not able to host people who are not participating in the retreat, even if they are friends, relatives, or partners of participants. We’ve learned from experience that having each person in the group fully share in the same set of experiences helps create the most beneficial environment for everyone involved. Thank you for understanding!
I’m ready to book a retreat! What’s the next step?
If you’re ready to book, please see our Retreats page for upcoming retreat dates. Click “Book Now” and follow the instructions to choose your accommodations, fill in your information, and submit payment. If you’d like to talk with someone first, you can schedule an exploratory call with a member of the Odyssey team here.
What is a psilocybin experience like?
Psilocybin experiences can vary widely between individuals, and the specifics of any particular experience are often unpredictable. However, there are commonalities across most experiences.
You may experience visual effects, color saturation, and solid objects may appear as if they’re moving or breathing. You may experience physical sensations differently, feel hot or cold, feel parts of your body in a different way or feel parts of your body you’ve never felt before. Your sense of time may become distorted, and it may seem to become compressed or expanded throughout the journey.
You may experience strong emotions – positive and negative – and you may experience two or more seemingly contradictory emotions at the same time. You may experience a deep and healing emotional release.You may see, imagine or remember people in your life, past and present, in particular those you have close relationships with.
You may confront and work through personal issues or past traumas. You may visit archetypal realms featuring figures, symbols or imagery from various cultures and mythological traditions. You may be visited by animals, or you may yourself transform into an animal.You may have the experience of everything as divine or holy, or of the alternate reality you perceive as being somehow “more real” than normal waking reality. You may lose your sense of being a separate self, and feel yourself dissolve into the universe or the cosmos. You may have a sense of deep interconnectedness and unity.
These are only some of the many possible aspects of a psychedelic journey. A psychedelic experience can be overwhelming, and it can be underwhelming. Upon consuming psilocybin, your experience may not be what you expect at all. Consensus among researchers, practitioners, and the broader community is that it’s beneficial to enter a journey with openness, and let go of expectations or desires for a specific experience or outcome.
What are the potential benefits of a psilocybin experience?
Psilocybin offers a range of potential benefits that can profoundly impact our mental and emotional well-being. It can provide us with insights into our core beliefs and sense of identity, and help us break out of negative patterns and habits. It can facilitate deep healing through emotional release. It can help us process and work through personal challenges and past traumas. It can lead to greater self compassion, and increased compassion for others, leading to better relationships.
Psilocybin has been shown to induce profound mystical-type experiences, often rated by study participants as among the most spiritually significant and personally meaningful of their lives.1,2,3 These experiences involve a dissolving of our normal sense of self and a sense of vast interconnectedness with all that exists. This can lead to an inner sense of renewal and revitalization, and a new, deepened appreciation for everyday life.
Psilocybin, when administered with psychological support, has demonstrated great potential in the treatment of major depressive disorder and treatment resistant depression.4,5,6 Psilocybin has also been shown to reduce depression and anxiety in cancer patients.7,8 Psilocybin may also hold promise for the treatment of smoking addiction and alcohol dependence.9,10,11,12
Why do you call it a journey?
A psychedelic experience has much in common with embarking on a journey. There’s an initial call, away from the comfortable and familiar and towards the unknown. It may require courage to follow the call. Although what lies ahead cannot be known, it will likely be filled with a great variety of fantastic new sights, deep emotions, intense sensations, and novel experiences.
A psilocybin journey unfolds over several hours (although it can sometimes feel like much more, or much less) and there’s often a sense of traveling through phases: embarkation, escalation or “come-up”, peak, de-escalation or “come-down”, and finally a return to normal waking consciousness. By the end you may feel like you’ve lived a lifetime in a single day. The result can be a glorious return to the present, returning “home” to the familiar world, transformed in both obvious and subtle ways.
Are you offering psychedelic therapy?
Odyssey doesn’t attempt or claim to treat any medical or mental health condition. While it’s common for people to have therapeutic experiences with psilocybin, an Odyssey experience is not a substitute for medical services, psychotherapy, or any other form of treatment.
At the same time, our protocols are based on best practices used in clinical trials and psychedelic research studies. In particular for our private sessions, the experience is similar to that of the psychedelic therapy process used in clinical trials.
Will a psilocybin experience cure me?
Odyssey doesn’t attempt or claim to treat any medical or mental health condition. While it’s common for people to have therapeutic experiences with psilocybin, an Odyssey experience is not a substitute for medical services, psychotherapy, or any other form of treatment.
We encourage viewing a psilocybin experience as part of an ongoing process, and not a “quick fix” or “silver bullet”. While certain research has shown significant, lasting benefits from a single session, it’s impossible to predict the exact outcome of a particular psychedelic experience for any individual.5
Ideally, a psilocybin experience takes place in the context of broader psychological and emotional work. This may include psychotherapy, which we recommend engaging in before and after your experience. It may also include practices such as meditation or journaling, which have been shown in research to support personal work with psychedelics.18
How many times will I need to do this?
Certain research has shown significant, lasting benefits from a single psilocybin session.5 Our experience matches this, and we’ve found that it’s common for individuals to receive substantial psychological and emotional benefits from a single psilocybin session. Immediately following the experience, these individuals often don’t feel like they need (or even would like) another strong psychedelic experience for some time. However, it’s impossible to predict the exact outcome of a particular psychedelic experience for any individual.
After their first experience, many people find it helpful to undergo a psychedelic experience once every few months, or a few times a year, as each session often provides something new and useful. Others find more, or less, frequent experiences are best for them. For some, a single session may provide so much that they don’t feel a need to do another.
Whether once a month, year, or decade - what feels right is up to you. In general, we recommend engaging in a thorough integration process following a psilocybin session, before planning another session.
Couldn’t I just take psilocybin mushrooms by myself?
It depends what you’re looking for. Advantages of a psilocybin session with Odyssey include professional guidance from licensed facilitators, curated preparation and integration support, a licensed service center setting designed for psychedelic experiences, and legality under Oregon’s state-level framework. Some individuals are comfortable taking psilocybin alone, but this can pose greater risk.
The experience is likely to be more unpredictable and may lead to unforeseen, potentially severe challenges. A survey study of over 600 lifetime psychedelic users found that factors such as lack of preparation, interactions with contraindicated prescription medications, lack of psychological support, and negative physical setting were associated with challenging experiences.17
Our view is that a psilocybin experience can be one of the most transformative and meaningful experiences of an individual’s life, and should not be taken lightly. Many find that accessing psilocybin services with professional support helps ensure the safest, most beneficial experience possible, and is more than worth the cost.
Are there safety concerns with psilocybin?
Safety is our highest priority. Stanford and Harvard-trained psychiatrists helped design our screening process and review applications. Our team follows the latest developments in psychedelic science, and updates our screening and intake processes based on the published literature.
Psilocybin is generally safe and well-tolerated, especially when administered in a controlled setting with professional supervision.14 Researchers in the UK deemed psilocybin mushrooms to be safer than alcohol, tobacco, cannabis, and over a dozen other substances.15Certain prescription medications and supplements may interact with psilocybin.19
Most of these interactions are not dangerous, however they may impact the experience in other ways (e.g. diminishing or blunting psilocybin’s psychedelic effects). Potential interactions with prescription medications and supplements are addressed in detail in our screening and intake process.Psilocybin can moderately increase heart rate and blood pressure.20 Individuals with a history of serious cardiac conditions or unmanaged high blood pressure should exercise caution. These potential risks are addressed in detail in our screening and intake process.
A strong psychedelic experience may exacerbate or trigger the onset of certain psychiatric disorders, such as schizophrenia.20 Individuals with a personal or family history of these conditions should exercise caution. These potential risks are addressed in detail in our screening and intake process.The greatest risk that a psilocybin experience poses for most people is that it may uncover psychological and emotional material that needs to be processed, which can lead to challenging experiences during the processing period.21
Through preparation, journey, and integration with support from licensed facilitators, Odyssey group retreats and private sessions are designed to provide the support needed for anyone to work through these challenges.
Learn more about how we're taking safety seriously.
Are there people who should not undergo a psilocybin experience?
Psilocybin is generally safe and well-tolerated, especially when administered in a controlled setting with professional supervision.14 Researchers in the UK deemed psilocybin mushrooms to be safer than alcohol, tobacco, cannabis, and over a dozen other substances.15
Psilocybin can moderately increase heart rate and blood pressure.20 Individuals with a history of serious cardiac conditions or unmanaged high blood pressure should exercise caution. These potential risks are addressed in detail in our screening and intake process.
A strong psychedelic experience may exacerbate or trigger the onset of certain psychiatric disorders, such as schizophrenia.20 Individuals with a personal or family history of these conditions should exercise caution. These potential risks are addressed in detail in our screening and intake process.
What if I have a challenging experience or “bad trip”?
Intense emotions such as sadness, anger, and fear can be and often are a part of a psilocybin experience. Commonly, challenges experienced during the journey are later viewed as positive, and ultimately felt to have been necessary or worthwhile.In one study analyzing over 200 challenging psychedelic experiences, more than 67% of respondents regarded the long-term consequences of their experience to be either positive or mostly positive, while less than 4% regarded the consequences to be either negative or mostly negative.16
Challenging experiences are also much less likely to occur when intentional preparation, integration, “set and setting”, professional support, and other considerations are taken into account. A survey study of over 600 lifetime psychedelic users found that factors such as lack of preparation, interactions with contraindicated prescription medications, lack of psychological support, and negative physical setting were associated with challenging experiences.17
When you book a group retreat or private session with Odyssey, we’ll send you a comprehensive package of resources to help prepare you for the journey. On a group retreat, you’ll participate in programming to further support this process. In a private session, you’ll have two hour long preparation calls with your facilitator before the journey. In both cases, your session will take place in a licensed service center designed for psychedelic experiences, with supervision from Odyssey’s highly vetted licensed facilitators.Although rare, some individuals do encounter challenges that endure beyond the session.
We’re committed to supporting you in working through whatever arises, even if that means extending additional services and support to you, at no additional cost.We take every measure to ensure each individual’s experience is safe, comfortable, and positive in both the short and long term. However, psilocybin experiences are not for everyone. Our screening and intake process is professionally designed to help us and you determine if a journey with Odyssey is a good fit for you.
Where can I learn more about psilocybin?
We recommend Michael Pollan’s bestseller How to Change Your Mind for a well-researched, approachable introduction to psychedelic science, or the Netflix series of the same name (episode 2 focuses on psilocybin). During an exploratory call or anytime throughout your experience with Odyssey, our team will also be happy to answer any questions you have.
References
1. Griffiths, R. R., Richards, W. A., McCann, U., & Jesse, R. (2006). Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance. Psychopharmacology, 187(3), 268–292. https://doi.org/10.1007/s00213-006-0457-5
2. Griffiths, R., Richards, W., Johnson, M., McCann, U., & Jesse, R. (2008). Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later. Journal of psychopharmacology (Oxford, England), 22(6), 621–632. https://doi.org/10.1177/0269881108094300
3. Griffiths, R. R., Johnson, M. W., Richards, W. A., Richards, B. D., McCann, U., & Jesse, R. (2011). Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects. Psychopharmacology, 218(4), 649–665. https://doi.org/10.1007/s00213-011-2358-5
4. Davis, A. K., Barrett, F. S., May, D. G., Cosimano, M. P., Sepeda, N. D., Johnson, M. W., Finan, P. H., & Griffiths, R. R. (2021). Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder: A Randomized Clinical Trial. JAMA psychiatry, 78(5), 481–489. https://doi.org/10.1001/jamapsychiatry.2020.3285
5. Raison, C. L., Sanacora, G., Woolley, J., Heinzerling, K., Dunlop, B. W., Brown, R. T., Kakar, R., Hassman, M., Trivedi, R. P., Robison, R., Gukasyan, N., Nayak, S. M., Hu, X., O'Donnell, K. C., Kelmendi, B., Sloshower, J., Penn, A. D., Bradley, E., Kelly, D. F., Mletzko, T., … Griffiths, R. R. (2023). Single-Dose Psilocybin Treatment for Major Depressive Disorder: A Randomized Clinical Trial. JAMA, 330(9), 843–853. https://doi.org/10.1001/jama.2023.14530
6. Carhart-Harris, R. L., Bolstridge, M., Rucker, J., Day, C. M., Erritzoe, D., Kaelen, M., Bloomfield, M., Rickard, J. A., Forbes, B., Feilding, A., Taylor, D., Pilling, S., Curran, V. H., & Nutt, D. J. (2016). Psilocybin with psychological support for treatment-resistant depression: an open-label feasibility study. The lancet. Psychiatry, 3(7), 619–627. https://doi.org/10.1016/S2215-0366(16)30065-7
7. Griffiths, R. R., Johnson, M. W., Carducci, M. A., Umbricht, A., Richards, W. A., Richards, B. D., Cosimano, M. P., & Klinedinst, M. A. (2016). Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial. Journal of psychopharmacology (Oxford, England), 30(12), 1181–1197. https://doi.org/10.1177/0269881116675513
8. Ross, S., Bossis, A., Guss, J., Agin-Liebes, G., Malone, T., Cohen, B., Mennenga, S. E., Belser, A., Kalliontzi, K., Babb, J., Su, Z., Corby, P., & Schmidt, B. L. (2016). Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: a randomized controlled trial. Journal of psychopharmacology (Oxford, England), 30(12), 1165–1180. https://doi.org/10.1177/0269881116675512
9. Garcia-Romeu, A., Griffiths, R. R., & Johnson, M. W. (2014). Psilocybin-occasioned mystical experiences in the treatment of tobacco addiction. Current drug abuse reviews, 7(3), 157–164. https://doi.org/10.2174/1874473708666150107121331
10. Johnson, M. W., Garcia-Romeu, A., & Griffiths, R. R. (2017). Long-term follow-up of psilocybin-facilitated smoking cessation. The American journal of drug and alcohol abuse, 43(1), 55–60. https://doi.org/10.3109/00952990.2016.1170135
11. Bogenschutz, M. P., Forcehimes, A. A., Pommy, J. A., Wilcox, C. E., Barbosa, P. C., & Strassman, R. J. (2015). Psilocybin-assisted treatment for alcohol dependence: a proof-of-concept study. Journal of psychopharmacology (Oxford, England), 29(3), 289–299. https://doi.org/10.1177/0269881114565144
12. Bogenschutz, M. P., Ross, S., Bhatt, S., Baron, T., Forcehimes, A. A., Laska, E., Mennenga, S. E., O'Donnell, K., Owens, L. T., Podrebarac, S., Rotrosen, J., Tonigan, J. S., & Worth, L. (2022). Percentage of Heavy Drinking Days Following Psilocybin-Assisted Psychotherapy vs Placebo in the Treatment of Adult Patients With Alcohol Use Disorder: A Randomized Clinical Trial. JAMA psychiatry, 79(10), 953–962. https://doi.org/10.1001/jamapsychiatry.2022.2096
13. Garcia-Romeu, A., Barrett, F. S., Carbonaro, T. M., Johnson, M. W., & Griffiths, R. R. (2021). Optimal dosing for psilocybin pharmacotherapy: Considering weight-adjusted and fixed dosing approaches. Journal of psychopharmacology (Oxford, England), 35(4), 353–361. https://doi.org/10.1177/0269881121991822
14. Nichols D. E. (2016). Psychedelics. Pharmacological reviews, 68(2), 264–355. https://doi.org/10.1124/pr.115.011478
15. Nutt, D. J., King, L. A., Phillips, L. D., & Independent Scientific Committee on Drugs (2010). Drug harms in the UK: a multicriteria decision analysis. Lancet (London, England), 376(9752), 1558–1565. https://doi.org/10.1016/S0140-6736(10)61462-6
16. Johnstad, Petter. (2021). Day trip to hell: A mixed methods study of challenging psychedelic experiences. Journal of Psychedelic Studies. 5. 10.1556/2054.2021.00155.
17. Simonsson, O., Hendricks, P. S., Chambers, R., Osika, W., & Goldberg, S. B. (2023). Prevalence and associations of challenging, difficult or distressing experiences using classic psychedelics. Journal of affective disorders, 326, 105–110. https://doi.org/10.1016/j.jad.2023.01.073
18. Griffiths, R. R., Johnson, M. W., Richards, W. A., Richards, B. D., Jesse, R., MacLean, K. A., Barrett, F. S., Cosimano, M. P., & Klinedinst, M. A. (2018). Psilocybin-occasioned mystical-type experience in combination with meditation and other spiritual practices produces enduring positive changes in psychological functioning and in trait measures of prosocial attitudes and behaviors. Journal of psychopharmacology (Oxford, England), 32(1), 49–69. https://doi.org/10.1177/0269881117731279
19. Sarparast, A., Thomas, K., Malcolm, B., & Stauffer, C. S. (2022). Drug-drug interactions between psychiatric medications and MDMA or psilocybin: a systematic review. Psychopharmacology, 239(6), 1945–1976. https://doi.org/10.1007/s00213-022-06083-y
20. Johnson, M., Richards, W., & Griffiths, R. (2008). Human hallucinogen research: guidelines for safety. Journal of psychopharmacology (Oxford, England), 22(6), 603–620. https://doi.org/10.1177/0269881108093587