TABLE 2.
Sample characteristics. Sociodemographic information for the children in the uninjured, typically developing (TD), mild traumatic brain injury (mTBI), and mild orthopedic injury (OI) groups (A), and injury characteristics (B) and postinjury symptom (C) for the children with mTBI or mild OI
| TD | OI | mTBI | |||
|---|---|---|---|---|---|
| n = 39 | n = 37 | n = 83 | p‐value | ||
| A. Sociodemographic characteristics | |||||
| Age [mean (SD) years] | 12.52 (2.34) | 13.07 (2.29) | 12.95 (2.26) | .526 | |
| Full scale IQ [mean (SD)] | 108.58 (14.74) | 108.59 (10.71) | 106.15 (12.43) | .519 | |
| Sex [n (%) male] | 21 (54) | 18 (49) | 53 (64) | .250 | |
| Race [n (%) White] | 22 (58) | 26 (72) | 65 (78) | .058 | |
| Diffusion‐weighted image RMS displacement [mean (SD) mm] | 0.29 (0.09) | 0.28 (0.13) | 0.29 (0.15) | .904 | |
| Density [mean (SD)] | 0.73 (0.05) | 0.72 (0.04) | 0.71 (0.04) | .282 | |
| B. Injury characteristics | |||||
| MRI scan day postinjury [mean (SD)] | 9.41 (3.64) | 8.59 (3.25) | .222 | ||
| Mechanism of injury [n (%)] | .034 | ||||
| Fall | 19 (51.4) | 28 (35.9) | |||
| Bicycle related | 5 (13.5) | 2 (2.6) | |||
| Motor vehicle collision | 0 (0.0) | 1 (1.3) | |||
| Struck object | 6 (16.2) | 23 (29.5) | |||
| Struck person | 5 (13.5) | 23 (29.5) | |||
| Other | 1 (2.7) | 1 (1.3) | |||
| Unknown | 1 (2.7) | 0 (0.0) | |||
| Injured during sport/recreational play [n (%)] | 31 (83.8) | 66 (84.6) | .999 | ||
| Loss of consciousness [n (%) yes] | — | 15 (18.5) | — | ||
| Glasgow coma scale score of 15 [n (%)] | — | 75 (90.4) | — | ||
| Extracranial injury [n (%)] | .017 | ||||
| Fracture | 17 (51.5) | 3 (25.0) | |||
| Sprain/soft tissue injury | 15 (45.5) | 5 (41.7) | |||
| Possible fracture | 1 (3.0) | 1 (8.3) | |||
| Laceration | 0 (0.0) | 3 (25.0) | |||
| C. Postinjury symptoms | |||||
| Total symptoms score [mean (SD)] | 8.00 (7.73) | 19.80 (12.35) | <.001 | ||
| Symptomatic [n (%)] | 2 (5.4) | 37 (45.1) | <.001 | ||
Note: RMS displacement computed for raw images (i.e., 30 volumes) using FSL eddy (Smith et al., 2004 ); Full Scale IQ per the 2‐subtest (i.e., Vocabulary and Matrix Reasoning) version of the Wechsler Abbreviated Scales of Intelligence (Wechsler, 2011); symptomatic children showed significant increase (i.e., z‐score > reliable change index) in postacute as compared with retrospective premorbid symptoms, based on parent Health and Behavior Inventory (Ayr et al., 2009) ratings.