Fig. 3

Standardized mean differences (SMD) before and after matching. PSM improved the balance on the investigated baseline characteristics with all SMD between groups decreasing to 0.1. SMD, indicates Standardized Mean Differences; ABT, Allogeneic Blood Transfusion; UCI, Urinary Catheter Insertion; SICU, Surgical-ICU; EICU, Emergency-ICU; MICU, Medical-ICU; NICU, Neurology-ICU; NSICU, Neurosurgical-ICU; GICU, Geriatrics-ICU; FEM, Femoral; SC, Subclavian; IJ, Internal jugular; ICD, International Classification of Diseases