Table 2.

Logistic linear regression analysis of associations between imaging signs and age, NIHSS score, and time to randomisation

	Age, adjusted for NIHSS score		NIHSS score, adjusted for age		Delay, adjusted for age and NIHSS score
	Odds ratio (95% CI)	p	Odds ratio (95% CI)	p	Odds ratio (95% CI)	p
Early ischaemic signs
Visible infarct	0·98 (0·97–0·98)	<0·0001	1·11 (1·09–1·12)	<0·0001	1·08 (1·01–1·16)	0·019
Hypoattenuation	0·98 (0·97–0·98)	<0·0001	1·10 (1·09–1·12)	<0·0001	1·10 (1·03–1·18)	0·006
Large lesion*	0·98 (0·97–0·99)	<0·0001	1·11 (1·09–1·13)	<0·0001	1·03 (0·94–1·12)	0·561
Swelling	0·98 (0·97–0·99)	<0·0001	1·09 (1·08–1·11)	<0·0001	1·04 (0·96–1·13)	0·302
Hyperattenuated artery	0·98 (0·97–0·98)	<0·0001	1·10 (1·09–1·12)	<0·0001	1·02 (0·94–1·10)	0·664
Pre-existing signs
Atrophy	1·11 (1·10–1·12)	<0·0001	0·99 (0·98–1·00)	0·179	0·98 (0·89–1·07)	0·621
Leukoaraiosis	1·09 (1·08–1·09)	<0·0001	0·99 (0·98–1·00)	0·221	0·99 (0·93–1·06)	0·843
Old infarct	1·03 (1·03–1·04)	<0·0001	0·99 (0·98–1·00)	0·017	0·98 (0·92–1·05)	0·566

Associations for visible infarct (the summary variable) are provided for completeness. Odds ratios and 95% CIs indicate the increased or decreased odds of the imaging sign being present for a 1 point change in NIHSS score, a 1 year change in age, or a 1 h increase in time to randomisation. Each of the eight imaging variables was used separately in two logistic regressions: first on age and NIHSS score (both linear) to give the values in the first two pairs of columns; and second on age, NIHSS score, and time to randomisation (all linear) to give the values in the last pair of columns. IST-3=third International Stroke Trial. NIHSS=National Institutes of Health Stroke Scale.

^*Large lesion defined as a combination of large and very large on IST-3 score.