Table 5. Multivariate analysis of death rate in patients with invasive meningococcal disease, Iceland, 1977–2004*.

Variable	OR (95% CI)	p value
Age	1.031 (1.016–1.048)	0.0001
Unique ST†	3.225 (1.311–7.934)	0.011
Positive CSF culture‡	0.381 (0.147–0.984)	0.046

*OR, odds ratio; CI, confidence interval; ST, sequence type; CSF, cerebrospinal fluid.
†Infection with an isolate with an ST unique to the country, in comparison to other, previously described STs.
‡Positive CSF culture only, in comparison to all other sources of positive culture, including blood only and blood and CSF.