The size of the study population

We read the original article “Measurement of blood lactate, D-dimer, and activated prothrombin time improves prediction of in-hospital mortality in adults blunt trauma” of Umebachi et al. published in March 2018, Volume 36, Issue 3, p347–532 with great pleasure. We think that the findings detected in this study will contribute to the scientific community. We send this letter to share our determination about the statistical analysis in the article.