Table 2

Multiple logistic regression analysis of PCI and NVAFV

	PCI		PCI+TIA
NVAFV
199.1–highest*	Ref	Ref	Ref	Ref
0–112.8	4.19 (1.76 to 9.95)	0.001	3.63 (1.63–8.10)	0.002
112.9–157.1	1.97 (0.93 to 4.16)	0.077	1.60 (0.81–3.17)	0.179
157.2–199	1.73 (0.80 to 3.74)	0.163	2.03 (1.02–4.01)	0.043
Contralateral VA stenosis*
Hypoplasia	Ref		Ref
<70%	0.91 (0.30 to 2.76)	0.868	0.95 (0.33–2.74)	0.920
≥70% or occlusion	3.32 (0.96 to 11.46)	0.058	3.23 (0.98–10.65)	0.055
Patients with severe anterior artery stenosis
NVAFV
199.1–highest*	Ref	Ref	Ref	Ref
0–112.8	14.03 (3.18 to 61.92)	<0.001	11.99 (3.10–46.3)	<0.001
112.9–157.1	1.55 (0.54 to 4.44)	0.416	1.60 (0.58–4.38)	0.363
157.2–199	1.04 (0.33 to 3.27)	0.950	1.91 (0.70–5.20)	0.207
Contralateral VA stenosis*
Hypoplasia	Ref		Ref
<70%	1.47 (0.27 to 8.15)	0.658	1.43 (0.29–6.96)	0.662
≥70% or occlusion	2.77 (0.45 to 16.88)	0.269	2.72 (0.50–14.93)	0.249
Patients without severe anterior artery stenosis
NVAFV
199.1–highest*	Ref	Ref	Ref	Ref
0–112.8	2.76 (0.85 to 8.95)	0.090	1.83 (0.65–5.17)	0.257
112.9–157.1	2.08 (0.68 to 6.35)	0.197	1.38 (0.52–3.68)	0.516
157.2–199	2.34 (0.76 to 7.25)	0.141	1.98 (0.74–5.33)	0.174
Contralateral VA stenosis
Hypoplasia	Ref		Ref
<70%	0.66 (0.16 to 2.94)	0.601	0.75 (0.18–3.05)	0.686
≥70% or occlusion	6.67 (0.91 to 49.04)	0.062	6.80 (0.98–47.13)	0.052

*Adjust for age, sex, contralateral VA stenosis, anterior severe stenosis.
NVAFV, net vertebral artery flow volume; PCI, posterior circulation infarction; TIA, transient ischaemic stroke; VA, vertebral artery.