Table 4.
Multivariate Cox Regression Analysis: Risk Factors for Death after TBIa
| Characteristics | Relative riskb | 95% confidence interval |
|---|---|---|
| Age at injury | 1.03 | 1.02–1.04 |
| Female | 0.47 | 0.41–0.54 |
| Level of education at injury | ||
| Less than high school (reference group) | – | – |
| High school/GED | 1.07 | 0.92–1.25 |
| Some college/associates degree | 1.16 | 0.96–1.41 |
| Bachelor’s degree | 0.76 | 0.61–0.94 |
| Post-bachelor’s degree | 1.02 | 0.82–1.28 |
| Marital status at injury | ||
| Married (reference group) | – | – |
| Never married | 0.73 | 0.59–0.91 |
| Divorced/widowed/separated | 1.37 | 1.20–1.57 |
| Employment status at injury | ||
| Competitively employed (reference group) | – | – |
| Unemployed | 2.25 | 1.60–3.18 |
| Retired | 2.21 | 1.72–2.85 |
| Student (part-time/full-time/special education) | 0.96 | 0.40–2.30 |
| Other (homemaker/volunteer/other) | 3.87 | 2.75–5.44 |
| Year of injury | 1.19 | 1.16–1.23 |
| Cause of injury | ||
| Vehicular (reference group) | – | – |
| Falls | 1.36 | 1.16–1.61 |
| Pedestrian | 0.91 | 0.64–1.28 |
| All sports | 0.30 | 0.05–2.01 |
| Violence | 1.00 | 0.71–1.40 |
| Other (including falling object) | 0.47 | 0.21–1.06 |
| Discharged to other than private home residence | 1.18 | 1.03–1.36 |
| FIM motor score at rehabilitation discharge | 0.98 | 0.98–0.99 |
| DRS score at rehabilitation discharge | 1.07 | 1.06–1.09 |
a
Based on 6113 cases with complete information.
b
Bolded relative risk figures are statistically significant.
TBI, traumatic brain injury: FIM, Functional Independence Measure; DRS, Disability Rating Scale.