From A Meta-Analysis of 90 Experiments on the Anomalous Anticipation of Random Future Events [1]:
> [...] a meta-analysis of 90 experiments from 33 laboratories in 14 different countries which yielded an overall positive effect in excess of 6 sigma with an effect size (Hedges’ g) of 0.09, combined z = 6.33, p = 1.2 × 10-10. A Bayesian analysis yielded a Bayes Factor of 7.4 × 10-9, greatly exceeding the criterion value of 100 for "decisive evidence" in favor of the experimental hypothesis (Jeffries, 1961). [...] The number of potentially unretrieved experiments averaging a null effect that would be required to reduce the overall effect size to a trivial value was conservatively calculated to be 520. An analysis of p values across experiments implies that the results were not a product of "p-hacking," [...].
> [...] a meta-analysis of 90 experiments from 33 laboratories in 14 different countries which yielded an overall positive effect in excess of 6 sigma with an effect size (Hedges’ g) of 0.09, combined z = 6.33, p = 1.2 × 10-10. A Bayesian analysis yielded a Bayes Factor of 7.4 × 10-9, greatly exceeding the criterion value of 100 for "decisive evidence" in favor of the experimental hypothesis (Jeffries, 1961). [...] The number of potentially unretrieved experiments averaging a null effect that would be required to reduce the overall effect size to a trivial value was conservatively calculated to be 520. An analysis of p values across experiments implies that the results were not a product of "p-hacking," [...].
[1] http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2423692