Table IV.

Logistic regression model for likelihood of death or permanent disability after off-road motorized vehicle crash

Variable	Odds ratio	95% Confidence interval	p
Helmet use	0.26	0.10–0.67	0.006
Vehicle type
ATV	1.0	–	–
Snowmachine	0.49	0.14–1.76	0.27
Motorbike	3.41	1.28–9.10	0.02
Age (per year increase)	1.05	0.92–1.20	0.46
Male sex	0.47	0.21–1.07	0.07
Ethnicity
White/other	1.0	–	–
Alaska Native/American Indian	0.44	0.17–1.11	0.08
Community type
Urban	1.0	–	–
Large rural	1.70	0.42–6.90	0.46
Small, isolated rural	0.97	0.38–2.46	0.94
Recent alcohol use	0.71	0.17–2.92	0.64
Recent drug use	2.00	0.55–7.25	0.29