Table 3. Annual Trends in Injury Severity Score, NTDB NSP, 2003-2013.
| Mechanism/Intent | Mean (95% CI) ISS, OLS | Median (95% CI) ISS, OLS | Mean (95% CI) ISS, Prais-Winstena | Median (95% CI) ISS, Prais-Winstena |
|---|---|---|---|---|
| Occupant motor vehicle crash | 0.03 (−0.12 to 0.17) | 0.08 (−0.04 to 0.20) | 0.03 (−0.16 to 0.21) | NA |
| Firearm | ||||
| Homicide | −0.03 (−0.19 to 0.12) | −0.04 (−0.10 to 0.03) | −0.03 (−0.20 to 0.15) | NA |
| Suicide | 0.08 (−0.10 to 0.25) | 0.31 (0.00 to 0.61)b | NA | NA |
| Unintentional death | 0.05 (−0.04 to 0.15) | −0.08 (−0.35 to 0.18) | NA | −0.08 (−0.34 to 0.18) |
Abbreviations: ISS, injury severity score; NA, not applicable; NTDB NSP, National Trauma Data Bank National Sample Program; OLS, ordinary least squares method.
a
Prais-Winsten models were included if the Durbin-Watson statistic was less than 1.95.
b
P < .05.