Table 1.
Demographic characteristics of cohort.
| Variables | Children with at least 5-year follow-up N=1,165 | Children with only 5-year follow-up n=807 | Children with 5-year and 11-year follow-up | p-value |
|---|---|---|---|---|
| Age in years, N (%) | ||||
| 0 | 496 (42.6) | 341 (42.3) | 155 (43.3) | 0.9404 |
| 1 | 516 (44.3) | 360 (44.6) | 156 (43.6) | |
| 2 | 153 (13.1) | 106 (13.1) | 47 (13.1) | |
| Male sex, N (%) | 710 (60.9) | 503 (62.3) | 207 (57.8) | 0.1456 |
| Race, N (%)* | ||||
| White | 590 (50.6) | 409 (50.7) | 181 (50.6) | 0.3163 |
| Black | 387 (33.2) | 260 (32.2) | 127 (35.5) | |
| Other | 188 (16.1) | 138 (17.1) | 50 (14.0) | |
| Injury Severity Score, ICISS | ||||
| mean (SD) | 0.68 (0.14) | 0.69 (0.13) | 0.67 (0.14) | |
| median (IQR) | 0.68 [0.60–0.77] | 0.69 [0.61–0.77] | 0.66 [0.60–0.76] | 0.0213* |
| Associated injuries, N (%) | ||||
| Fractures | ||||
| skull | 471 (40.4) | 322 (39.9) | 149 (41.6) | 0.5812 |
| trunk or spine | 164 (14.1) | 122 (15.1) | 42 (11.7) | 0.1252 |
| upper extremity | 112 (9.6) | 79 (9.8) | 33 (9.2) | 0.7601 |
| lower extremity | 132 (11.3) | 103 (12.8) | 29 (8.1) | 0.0205** |
| any of the above | 627 (53.8) | 434 (53.8) | 193 (53.9) | 0.9669 |
| Intracranial Injuries | ||||
| epidural hemorrhage | 52 (4.5) | 39 (4.8) | 13 (3.6) | 0.3596 |
| subdural hemorrhage | 730 (62.7) | 508 (63) | 222 (62.0) | 0.7601 |
| subarachnoid hemorrhage | 199 (17.1) | 130 (16.1) | 69 (19.3) | 0.1854 |
| cerebral edema | 123 (10.6) | 101 (12.5) | 22 (6.2) | 0.0011*** |
| cerebral contusion | 73 (6.3) | 48 (6.0) | 25 (7.0) | 0.5011 |
| cerebral concussion | 34 (2.9) | 27 (3.4) | 7 (1.96) | 0.1933 |
| any of the above | 929 (79.4) | 634 (78.6) | 295 (82.4) | 0.1325 |
| Retinal hemorrhage | 482 (41.4) | 303 (37.6) | 179 (50.0) | <0.0001**** |
Other race included Asian, Native American, Pacific Islander, other, or undocumented. Abbreviations: ICISS: ICD-9-Based Injury Severity Score; SD: standard deviation; IQR: interquartile range. P value comparing the children with only 5-year follow-up and the children with both 5-year and 11-year follow-up.
*
Effect size of 0.46, which correlates with a small difference.
**
Effect size of 0.15, which correlates with a trivial difference.
***
Effect size of 0.22, which correlates with a small difference.
****
Effect size of 0.25, correlates with a small difference.