Variables Standardized differences Standardized differences Variance ratio Variance ratio
Raw Matched Raw Matched
Age (years) 0.59 -0.03 0.43 0.79
Gender -0.10 -0.10 0.98 0.98
Hypertension 0.34 -0.05 0.76 1.02
Diabetes mellitus 0.13 -0.03 1.23 0.95
Preoperative serum creatinine 0.35 0.20 1.47 0.88
Chronic pulmonary disease 0.11 0.07 1.18 1.11
Peripheral vascular disease 0.20 -0.02 1.77 0.94
Previous myocardial infarction 0.14 -0.05 1.55 0.84
Poor left ventricular function 0.31 0.04 2.52 1.17