Table 2.

Participant characteristics.

Demographic information	Mean	Std. Deviation	Minimum	Maximum	Cronbach's α
Age	32.25	10.20	19.00	74.00	-
Education level (1–6)	3.86	0.77	2.00	6.00	-
Income level (1–5)	2.77	0.89	1.00	5.00	-
Past use of psychedelics
Cumulative frequency	7.70	26.72	1.00	500.00	-
Time since last use (years)	2.93	5.48	0.00	45.83	-	a
Average use of psychedelics [0–8]	2.62	1.93	0.00	8.00	-
Average dose (1–3)	1.42	0.58	1.00	3.00	-	b
Mystical Experience Questionnaire [0–5]	2.62	0.94	0.07	4.77	0.95
Psychological Insight Questionnaire [0–5]	1.82	1.09	0.00	4.57	0.96
Other questionnaires
Non-physicalist beliefs (1–7)	4.07	0.96	1.00	6.67	0.73
Holmes et al. Spirituality factor (1–5)	2.75	0.99	1.00	5.00	0.95
Holmes et al. Naturalism factor (1–5)	3.21	0.75	1.00	5.00	0.88
The Warwick-Edinburgh Mental Wellbeing Scale (1–5)	3.31	0.71	1.00	5.00	0.93
Peace of Mind Scale (1–5)	3.00	0.88	1.00	5.00	0.90
Anxiety (1–4)	2.05	0.77	1.00	4.00	0.91
Depression (1–4)	1.90	0.70	1.00	4.00	0.90

Education level was measured on ordinal scale from 1 to 6 (1 = Primary education; 2 = Lower Secondary education, 3 = Upper Secondary or Vocational education, 4 = University: Bachelor’s degree, 5 = University: Master’s degree, 6 = University: Doctoral degree).

Income level was measured on an ordinal scale from 1 to 5, estimating difference to the average in one's homecountry (1 = Much below average; 2 = Slightly below average; 3 = Average; 4 = Slightly above average; 5 = Much above average).

Average use of psychedelics was estimated on an ordinal scale from 0 to 8 (0 = Never; 1 = Once every four years or less often; 2 = Once every three years; 3 = Once every two years; 4 = Once a year; 5 = Few times a year; 6 = Monthly; 7 = Weekly; and 8 = Daily). Average dose was estimated on an ordinal scale from 1 to 3 (1 = Small; 2 = Medium; 3 = Strong) with a "Don't know" option. Examples of typical doses of commonly used substances were given.

^aMissingness was 3.

^bMissingness was 135 due to not knowing the dose.