Association of cervical artery dissection with cervical spinal manipulation relative to E&M using 10:1 sex- and age-matched population controls

	Vertebral artery dissection				Carotid artery dissection
	n controls	n	Odds ratio (95% CI)	p-value	n controls	n	Odds ratio (95% CI)	p-value

Exposure Past 7 days

E&M Only	27	113	Ref.		30	114	Ref.
Any CSM	60	47	0.17 (0.09, 0.32)	< 0.001	69	25	0.08 (0.04, 0.16)	< 0.001

Neither CSM nor E&M	23,256	2177	0.02 (0.01, 0.04)	< 0.001	29,008	2777	0.03 (0.02, 0.04)	< 0.001

Exposure Past 14 days

E&M Only	61	168	Ref.		67	197	Ref.
Any CSM	95	63	0.27 (0.17, 0.43)	< 0.001	34	34	0.09 (0.06, 0.16)	< 0.001
Neither CSM nor E&M	23,187	2106	0.04 (0.03, 0.05)	< 0.001	28,919	2685	0.04 (0.03, 0.05)	< 0.001

Exposure Past 30 days

E&M Only	109	223	Ref.		146	268	Ref.
Any CSM	155	80	0.32 (0.22, 0.47)	< 0.001	185	48	0.16 (0.10, 0.24)	< 0.001
Neither CSM nor E&M	23,079	2034	0.06 (0.05, 0.08)	< 0.001	28,776	2600	0.07 (0.06, 0.09)	< 0.001

E&M = evaluation and management;
Ref = referent group;
CI = confidence interval

Table 2.