An article in Nature Reviews Neuroscience about low sample sizes suggests, according to The Guardian, that “the likelihood that any claimed effect (based on passing a conventional level of statistical significance) actually is true is only 50%. That’s a 50/50 chance that any positive effects are spurious. For a confirmatory study with four to one pre-study odds, the chance that any positive effects are spurious is reduced to 25%.”
Of further interest:
Unreliable neuroscience? Why power matters (The Guardian)
Neuroscience Cannae Do It Cap’n, It Doesn’t Have the Power (National Geographic)
