Clinical trials play a decisive role in the drug approval processes. By completing a p-curve analysis of a newly compiled data set that consists of thousands of clinical trials, we substantiate that the occurrence of p-hacking in clinical trials is not merely hypothetical. Medical and...

This paper provides concise, nontechnical, step-by-step guidelines on how to conduct a modern meta-analysis, especially in social sciences. We treat publication bias, p-hacking, and heterogeneity as phenomena meta-analysts must always confront. To this end, we provide concrete methodological...

Meta-analysis upweights studies reporting lower standard errors and hence more precision. But in empirical practice, notably in observational research, precision is not given to the researcher. Precision must be estimated, and thus can be p-hacked to achieve statistical significance. Simulations...