Table 2.
Standardized difference for each covariate before and after propensity score matching
| Variable | Unmatched Sample | Matched Sample |
|---|---|---|
| Age | 0.175 | 0.002 |
| BMI | 0.048 | 0.011 |
| Liu comorbidity score | 0.103 | 0.007 |
| Time to study entry | 0.245 | 0.005 |
| Albumin | 0.043 | 0.007 |
| Hemoglobin | 0.02 | 0.017 |
| GFR | 0.055 | 0.006 |
| Sex | 0.292 | 0.004 |
| White | 0.238 | 0.003 |
| Black | 0.269 | 0.006 |
| Other race | 0.03 | 0.005 |
| Depression | 0.124 | 0.019 |
| Dementia | 0.112 | 0.017 |
| Institutionalized/inability to ambulate/transfer | 0.215 | 0 |
| Acute myocardial Infarction | 0.015 | 0.001 |
| Stroke | 0.117 | 0.017 |
Standardized bias was calculated by difference in means divided by SD of the total sample. A standardized bias <0.10 is considered a balance of the potential confounder between arteriovenous fistula and graft groups. BMI, body mass index.