To the Editor Dr Robertson and colleagues1 conducted a 2 × 2 factorial design randomized clinical trial of 200 patients with traumatic brain injury to test the effect of 2 approaches to transfusion threshold and erythropoietin therapy on neurological outcome. Unfortunately, their findings that erythropoietin failed to demonstrate an outcome benefit reflect substantial lack of statistical power.
Nichol A, Little L, French C. Erythropoietin for Traumatic Brain Injury. JAMA. 2014;312(18):1928–1929. doi:10.1001/jama.2014.12738