What conclusions can we draw about Rhine’s overall research program? By 1940, 33 experiments had accumulated, involving almost a million trials, with protocols which rigorously excluded possible sensory clues (e.g., by introducing distance and/or barriers between sender and receiver, or by employing precognition protocols (i.e., where the target has not yet been selected at the time subjects make their responses).
Twenty seven (27) of the 33 studies produced statistically significant results — an exceptional record, even today. Furthermore, positive results were not restricted to Rhine’s lab. In the five years following Rhine’s first publication of his results, 33 independent replication experiments were conducted at different laboratories. Twenty (20) of these (or 61%) were statistically significant (where 5% would be expected by chance alone).
A meta-analysis was done specifically for precognition experiments conducted between the years 1935 – 1987. (Honorton, C., & Ferrari, D. [1989]. Meta-analysis of forced-choice precognition experiments 1935 – 1987. Journal of Parapsychology, vol 53, 281 – 308). This included 309 studies, conducted by 62 experimenters. The cumulative probability associated with the overall results was p = 10-24 (that is equivalent to .000000000000000000000001 where .05 is considered statistically significant). The scientific evidence for precognition, the most provocative of all parapsychological phenomena, stands of firm statistical grounds.
