TABLE 2.
Demographic Characteristics of the Study Cohort
| Variable | Comparisona N = 37 834 | mTBI N = 18 917 | P | Odds Ratio (95% CI) |
|---|---|---|---|---|
| Age groups, y (n) | 1.000 | N/A | ||
| 0–5 | 11 (4338) | 11 (2169) | ||
| 6–9 | 13 (4792) | 13 (2396) | ||
| 10–13 | 28 (10476) | 28 (5238) | ||
| 14–17 | 48 (18 228) | 48 (9144) | ||
| Sex (n) | 1.000 | N/A | ||
| Female | 36 (13 530) | 36 (6756) | ||
| Male | 64 (24 304) | 64 (12 152) | ||
| Race/ethnicity (n) | 1.000 | N/A | ||
| White (non-Hispanic) | 49 (18 678) | 49 (9339) | ||
| Hispanic/Latino | 24 (8949) | 24 (4476) | ||
| Asian/Pacific Islander | 10 (3608) | 10 (1807) | ||
| Black/African American | 9 (3493) | 9 (1746) | ||
| Other race/ethnicity | 8 (3106) | 8 (1549) | ||
| Low-income households - % (n) | 9 (3574) | 8 (1552) | <.0001b | 0.86 (0.81–0.91)b |
| Previous diagnoses (n) | ||||
| Affective disorders | 12 (4449) | 8 (1489) | <.0001b | 0.64 (0.60–0.68)b |
| Behavioral disorders | 10 (3643) | 7 (1273) | <.0001b | 0.68 (0.63–0.72)b |
mTBI, mild traumatic brain injury; N/A, not available.
a
Two comparison patients were selected for each mTBI patient. Comparisons have the same “reference date” (ie, corresponding to the injury date of the paired mTBI patient). mTBI patients were matched to their respective comparisons using Mahalanobis distance function based on sex, age, and race/ethnicity.
b
Statistically significant risk ratios (P < .05).