Patient demographics, hospital course, and CNI scores
| Sample size per variable | All | ED utilization within 30 days | No ED utilization within 30 days | P value | Effect size Cohen’s d or OR (95% CI) | |
| ED utilization | 3245 | – | 309 (9.5%) | 2936 (90.5%) | – | |
| Age | 3245 | 36.5±16.3 | 38.3±15.7 | 36.3±16.4 | 0.034 | d=0.12, negligible |
| Gender, male | 3245 | 2119 (65.3%) | 218 (70.6%) | 1901 (64.7%) | 0.042 | OR: 1.3 (1.0 to 1.7) |
| Injury Severity Score | 2944 | 8.0±8.1 | 10.4±8.7 | 7.7±8.0 | <0.001 | d=0.32, small |
| Length of stay | 3.7±5.7 | 6.4±8.1 | 3.4±5.3 | <0.001 | d=0.44, small | |
| Illicit drugs | 946 (29.2%) | 131 (42.4%) | 815 (27.8%) | <0.001 | OR: 1.9 (1.5 to 2.4) | |
| Alcohol above legal limit | 3245 | 659 (20.3%) | 75 (24.3%) | 584 (19.9%) | 0.069 | |
| Penetrating Injury | 3245 | 633 (19.5%) | 106 (34.3%) | 527 (17.9%) | <0.001 | OR: 2.4 (1.9 to 3.1) |
| Complication, one or more | 3245 | 213 (6.6%) | 54 (17.5%) | 159 (5.4%) | <0.001 | OR: 3.7 (2.6 to 5.2) |
| Comorbidity, one or more | 3245 | 2161 (66.6%) | 214 (69.3%) | 1947 (66.3%) | 0.297 | |
| Race/Ethnicity | 3245 | 0.023 | ||||
| American Indian/Alaskan | 134 (4.1%) | 12 (3.9%) | 122 (4.2%) | |||
| Asian | 26 (0.8%) | 1 (0.3%) | 25 (0.9%) | |||
| African–American | 409 (12.6%) | 56 (18.1%) | 353 (12.0%) | |||
| Hispanic | 1411 (43.5%) | 121 (39.2%) | 1290 (43.9%) | |||
| Other | 174 (5.4%) | 11 (3.6%) | 163 (5.6%) | |||
| Caucasian | 1091 (33.6%) | 108 (35.0%) | 983 (33.5%) | |||
| Insurance | 3237 | 0.002 | ||||
| Private | 807 (24.9%) | 62 (20.1%) | 745 (25.4%) | |||
| Government | 1815 (56.1%) | 203 (65.7%) | 1612 (55.1%) | |||
| Uninsured | 615 (19.0%) | 44 (14.2%) | 571 (19.5%) | |||
| CNI score | 3222 | 4.2±0.8 | 4.4±0.7 | 4.2±0.8 | <0.001 | d=0.27, small |
| CNI 4–5 (vs. 1–3) | 3222 | 2535 (78.6%) | 268 (87.6%) | 2266 (77.7%) | <0.001 | OR: 2.0 (1.4 to 2.9) |
| CNI score category | 3222 | 0.001 | ||||
| 1.0–1.9 | 107 (3.3%) | 5 (1.6%) | 102 (3.5%) | |||
| 2.0–2.9 | 171 (5.3%) | 9 (2.9%) | 162 (5.6%) | |||
| 3.0–3.9 | 410 (12.7%) | 24 (7.8%) | 386 (13.2%) | |||
| 4.0–4.9 | 2159 (67.0%) | 212 (69.3%) | 1947 (66.8%) | |||
| 5 | 375 (11.6%) | 56 (18.3%) | 319 (10.9%) |
CNI, Community Need Index; ED, emergency department.