Table 1.

Cohort characteristics

	Head CT performed (n = 2548)	NO head CT performed (n = 238)	P-value (z test for proportions)
Sex	0.59	0.42	P < 0.00001
Median age	40 years	27 years
Fall mechanism	0.51	0.37	P < 0.00001
MVC mechanism	0.33	0.36	NS
LOC	0.49	0.03	P < 0.00001
AOC	0.31	0.12	P < 0.00001
Associated seizure	0.02	0.01	NS
Associated vomiting	0.06	0.03	NS
PTA	0.29	0.07	P < 0.00001
ED GCS 13	0.03	0	P = 0.0067
ED GCS 14	0.11	0.02	P < 0.00001
ED GCS 15	0.86	0.98	P < 0.00001