Fig. 2.
Proportion of studies as a function of the level of power to detect a small (d = 0.2), medium (d = 0.5) and large (d = 0.8) effect size.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.