Median Daily Lowest Levels of Blood Hemoglobin in the Lower-Threshold Group and the Higher-Threshold Group. The I bars indicate the 25th and 75th percentiles. From The New England Journal of Medicine, Lars B. Holst et al, Lower versus Higher Hemoglobin Threshold for Transfusion in Septic Shock, 371, 1381-91. Copyright © 2014 Massachusetts Medical Society. Reprinted with permission from Massachusetts Medical Society.