Table 1.

Statistical comparisons for secondary outcomes.

Measure	Placebo-controlled sample (baseline vs placebo)		Placebo-controlled sample (placebo vs DMT)		Prospective sample (baseline vs DMT)
	Statistic	Effect size	Statistic	Effect size	Statistic	Effect size
Wellbeing (WHO-5)	t = 0.92	d = 0.26	z = 1.87	r = 0.52	t = 0.27	d = 0.34
Nature-relatedness (NR-5)	t = 1.2	d = 0.36	t = 0.77	d = 0.44	z = 2.14	r = 0.52
Gratitude (GQ-6)	t = 0.09	d = 0.024	t = 1.51	d = 0.42	t = 2.82*	d  = 1.23
Optimism (LOT-R)	t = 2.05	d = 0.57	t = 0.37	d = 0.10	t = 1.76*	d = 0.59
Meaning in life (MLQ)	t = 0.17	d = 0.14	t = − 0.04	d = − 0.01	t = 0.52	d = 0.19

The table shows statistical comparisons between 1 week post-DMT vs 1 week post-placebo (placebo-controlled data) and between 2 weeks post-DMT vs baseline. *p < 0.05 two-tailed (uncorrected). No significant comparisons survived Bonferroni correction for multiple comparisons.