Table 2 Descriptive statistics of predictors by LOS*
|  | 0–2 days (n = 15,696) | 2–4 days (n = 15,122) | 4–7 days (n = 7226) |  >  = 7 days (n = 4165) |
|---|---|---|---|---|
Demographics | Â | Â | Â | Â |
 Age, years (mean, SD) | 58.09 (17.59) | 57.12 (19.10) | 57.07 (20.19) | 57.40 (21.44) |
 Sex = female (n, %) | 7792 (49.6%) | 8839 (58.5%) | 3820 (52.9%) | 1873 (45.0%) |
Race (n, %) | Â | Â | Â | Â |
    NHW** | 12,020 (76.6%) | 10,646 (70.4%) | 5173 (71.6%) | 2935 (70.5%) |
NHB*** | 2567 (16.4%) | 3364 (22.2%) | 1477 (20.4%) | 869 (20.9%) |
    Hispanic | 342 (2.2%) | 371 (2.5%) | 181 (2.5%) | 99 (2.4%) |
    Other | 767 (4.9%) | 741 (4.9%) | 395 (5.5%) | 262 (6.3%) |
Smoke status = Ever (n,%) | 4887 (31.1%) | 4893 (32.4%) | 2707 (37.5%) | 1741 (41.8%) |
BMI (n, %) | Â | Â | Â | Â |
    Underweight | 478 (3.0%) | 605 (4.0%) | 389 (5.4%) | 311 (7.5%) |
    Normal | 3248 (20.7%) | 3235 (21.4%) | 1767 (24.5%) | 1108 (26.6%) |
    Overweight | 5076 (32.3%) | 4319 (28.6) | 2167 (30.0%) |  1253 (30.1%) |
    Obese | 6866 (43.7%) | 6950 (46.0%) | 2895 (40.1%) | 1490 (35.8%) |
Service utilizations | Â | Â | Â | Â |
    Hospital encounter counts (mean, SD) | 0.24 (0.74) | 0.26 (0.73) | 0.36 (0.93) | 0.55 (1.13) |
    Ambulatory encounter counts (mean, SD) | 15.76 (17.12) | 16.77 (18.29) | 17.99 (19.45) | 20.67 (22.90) |
    Emergency encounter counts (mean, SD) | 0.16 (0.83) | 0.20 (0.83) | 0.23 (0.86) | 0.32 (2.20) |