Figure 1.

Preferred Reported Items for Systematic Reviews and Meta-Analysis (PRISMA) flow-diagram of database search, study selection and articles included in this systematic review with meta-analysis. * The works from Griffiths et al., 2016 [6], Ross et al., 2016 [19] and Grob et al., 2011 [20] were divided into several effect sizes based on different times of follow-up after psilocybin administration. (The division of each work in several effect sizes is indicated by the letters in unpaired parenthesis in Table 1).