Fig. 1From: Low muscle mass is an independent risk factor for postoperative blood transfusion in total knee arthroplasty: a retrospective, propensity score-matched cohort studyReceiver operating characteristic curve (ROC) for prediction of postoperative transfusion based on skeletal muscle index (SMI). The ROC analysis suggested an optimal SMI cut-off of 5.6 kg/m2, with an AUC value of 0.797 (0.633–0.96), sensitivity of 66.7%, and specificity of 86.2%Back to article page