On the Difference between a-priori and Observed Statistical Power — A Comment on “Statistical Power And Sample Size Calculations: A Primer for Pediatric Surgeons”

Statistical literacy has been found to be poor in medical students and their educators [1], in pathologists [2], medical [3], and surgical residents [4]. In light of these results, the importance of an easy to use guideline such as those by Staffa & Zurakowski [5] cannot be overemphasized. Their effort to make power analysis and sample size calculation easily accessible for pediatric surgeons is to be commended, especially in light of the recent discussion about observed power in the surgical literature.