Abstract

Conducted a meta-analysis of 78 free-response ESP studies in which Ss were not in an altered state of consciousness. The evidence for an above-chance effect size was significant and did not appear to be due to a few exceptional studies. Crude selective reporting appears to be an implausible counterexplanation of the overall cumulation, and there are no strong positive indications that methodological artifacts played a role in producing above-chance results. However, the failure to report that the outcome measure was preplanned in 96% of the studies and the frequent use of multiple measures raises the possibility of widespread post hoc data selection problems in the studies. No data are available to resolve the question of whether or not this threat to the database\'s validity is merely potential.