American journal of therapeutics
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The P values tell us the chance of making a type I error of finding a difference where there is none. In the 1970s, exact P values were laborious to calculate and were generally approximated from statistical tables, in the form of P < 0.01 or 0.05 < P < 0.10, etc. In the past decades with the advent of computers, it became easy to calculate exact P values such as 0.84 or 0.007. ⋯ Instead of concluding significantly yes/no, we are able to consider levels of probabilities from very likely to be true to very likely to be untrue. Very large P values are not compatible with a normal gaussian frequency distribution; very small P values do not completely confirm prior expectations. They must be scrutinized and may have been inadequately improved.