Patient characteristics associated with duration of stay after admission to general internal medicine
| Characteristic | Duration of stay; no. (%) of patients* | p value‡ | ||
|---|---|---|---|---|
| < 24 h n = 4245 | 24–72 h n = 13 442 | > 72 h† n = 38 368 | ||
| Age, yr, median (IQR) | 63 (45–78) | 67 (50–81) | 74 (59–84) | < 0.001 |
| Female sex | 2155 (50.8) | 6722 (50.0) | 19 026 (49.6) | 0.3 |
| Charlson Comorbidity Index score | < 0.001 | |||
| 0 | 1846 (43.5) | 4666 (34.7) | 8809 (23.0) | |
| 1 | 962 (22.7) | 3061 (22.8) | 7737 (20.2) | |
| 2 | 557 (13.1) | 2210 (16.4) | 6785 (17.7) | |
| ≥ 3 | 880 (20.7) | 3505 (26.1) | 15 037 (39.2) | |
| Transported via ambulance | 1531 (36.1) | 5700 (42.4) | 21 533 (56.1) | < 0.001 |
| Admitted to general internal medicine at a study site in prior 30 d* | 372 (8.8) | 1283 (9.5) | 5315 (13.8) | < 0.001 |
| Laboratory-based Acute Physiology Score, mean ± SD | 13.0 ± 12.4 | 16.3 ± 13.9 | 21.4 ± 17.1 | < 0.001 |
| Admitted on weekend | 929 (21.9) | 3516 (26.2) | 10 152 (26.4) | < 0.001 |
| Time of admission | < 0.001 | |||
| Day (0800–1659:59) | 398 (9.4) | 2832 (21.1) | 8398 (21.9) | |
| Evening (1700–2400) | 1795 (42.3) | 5156 (38.4) | 14 828 (38.6) | |
| Night (0000:01–0759:59) | 2052 (48.3) | 5454 (40.6) | 15 142 (39.5) | |
Note: IQR = interquartile range, SD = standard deviation.
↵* Except where noted otherwise.
↵† Patients who left hospital against medical advice, died or were transferred to another acute inpatient, rehabilitation or palliative care facility were categorized as having a stay of more than 72 hours.
↵‡ χ2 analysis for categorical variables, Kruskall–Wallis test for continuous variables.