Table 3. Multivariate model for predicting unfavorable outcome.

	Odds Ratio		95% Confidence Limits			P-value
History of substance abuse	1.34		0.37		4.84	0.66
Hemorrhage volume (mL)	1.01		1.00		1.02	0.13
Glasgow Coma Score	0.72		0.64		0.81	<0.0001*
Gender						0.04*
Age						0.12
Age-by-gender interaction	0.09		0.01		1.27	0.002*
Female gender at age 30 years
Female gender at age 50 years	0.44		0.10		1.97
Female gender at age 70 years	2.25		0.81		6.24

The odds ratio for age-by-gender interaction differs for each point along the age curve, e.g., 30 (premenopausal), 50 (menopausal), and 70 (postmenopausal). C-index for the multivariable model is 0.88. *P values < 0.05 were considered significant. Note: mL = milliliter.