One of the hallmarks of a real phenomenon is that its magnitude is replicable by various researchers working under similar conditions. The results of the overall SRI analysis are consistent with results of similar experiments in other laboratories. For instance, an overview of forced choice precognition experiments (Honorton and Ferrari, 1989) found an average "effect size" per experimenter of 0.033, whereas all forced choice experiments at SRI resulted in a similar effect size of .052. The comparison is not ideal since the SRI forced choice experiments were not necessarily precognitive and they used different types of target material than the standard card-guessing experiments.
Methodologically sound remote viewing has not been undertaken at other laboratories, but a similar regime called the ganzfeld (described in more detail in Section 5) has shown to be similarly successful. The largest collection of ganzfeld experiments was conducted from 1983 to 1989 at the Psychophysical Research Laboratories in Princeton, NJ. Those experiments were also reported by separating novices from experienced subjects. The overall effect size for novice remote viewing at SRI was 0.164, while the effect size for novices in the ganzfeld at PRL was a very similar 0.17. For experienced remote viewers at SRI the overall effect size was 0.385; for experienced viewers in the ganzfeld experiments it was 0.35. These consistent results across laboratories help refute the idea that the successful experiments at any one lab are the result of fraud, sloppy protocols or some methodological problem and also provide an indication of what can be expected in future experiments.