Effect of changes in prior probability and statistical power on false positive report probability (FPRP) when the α level is .05. FPRP shown is for a P value at or just below α; FPRP will be lower when the observed P value is substantially below α. A low FPRP is achievable only for high prior probabilities. Moreover, statistical power has an important impact on FPRP, except for particularly high and low prior probabilities. For example, for a prior probability of 0.1, the FPRPs are 0.69, 0.47, 0.36, and 0.31 for statistical powers of 0.2, 0.5, 0.8, and 1.