Table 1.
Population Characteristics
| Variable | Derivation cohort (n = 968) |
Validation cohort (n = 323) |
|---|---|---|
| Age, y | 52.5 ± 10.1 | 52.6 ± 10.8 |
| Male sex, n (%) | 656 (67.7) | 214 (66.2) |
| Race/ethnicity, n (%) | ||
| Non-Hispanic Caucasian | 318 (32.9) | 100 (31.0) |
| Hispanic Caucasian | 390 (40.3) | 138 (42.7) |
| Black | 215 (22.2) | 73 (22.6) |
| Other | 45 (4.6) | 12 (3.7) |
| Insurance, n (%) | ||
| Medicaid | 273 (28.2) | 95 (29.4) |
| Medicare | 131 (13.5) | 53 (16.4) |
| Charity | 292 (30.2) | 84 (26.0) |
| Other | 272 (28.1) | 91 (28.2) |
| Single marital status, n (%) | 654 (68.0) | 209 (65.5) |
| English as primary language, n (%) | 710 (73.8) | 235 (73.6) |
| White blood cell count, ×109/L | 5.8 ± 3.6 | 5.5 ± 2.9 |
| Hematocrit, % | 33.9 ± 5.6 | 34.9 ± 5.6 |
| Platelet count, ×109/L | 103.5 ± 71.1 | 96.7 ± 60.7 |
| Sodium level, mEq/L | 132.7 ± 5.1 | 132.7 ± 5.0 |
| Creatinine level, mg/dL | 1.5 ± 2.1 | 1.4 ± 2.0 |
| AST level, U/L | 89.9 ± 104.9 | 93.8 ± 195.9 |
| ALT level, U/L | 49.3 ± 66.8 | 47.3 ± 65.7 |
| Bilirubin level, mg/dL | 3.2 ± 4.2 | 2.9 ± 3.2 |
| MELD score | 15.3 ± 6.1 | 15.3 ± 5.9 |
| History of HIV/AIDS, n (%) | 51 (5.2) | 12 (3.7) |
| Length of index hospitalization, d | 7.3 ± 6.0 | 5.2 ± 5.6 |
| Number of admissions in the year before index hospitalization | 1.0 ± 1.6 | 1.1 ± 1.8 |
| Number of address changes in the year before index hospitalization | 1.0 ± 1.8 | 1.1 ± 1.9 |
| Active alcohol use, n (%) | 160 (16.5) | 56 (17.3) |
| Active cocaine use, n (%) | 52 (5.3) | 11 (3.4) |
| Residence in high-risk census tract, n (%) | 149 (15.3) | 53 (16.4) |
| Presented to emergency room between 6 PM and 6 AM, n (%) | 648 (66.9) | 222 (68.7) |
| Admitted to medicine service, n (%) | 915 (94.5) | 291 (90.0) |
| History of leaving AMA, n (%) | 34 (3.5) | 3 (0.9) |
AMA, against medical advice; AST, aspartate aminotransferase.