Table 1

Characteristics of the selection and comparability of cases and controls in the included studies

		Cases					Controls		Accounted for confounders?	Newcastle–Ottawa scale quality score
Study	Study design	Spontaneous haemorrhage?	Clinically symptomatic?	ICH described on imaging?	ICH location(s)	Age, years (mean(range))	Comorbidities	Age (years) (mean or range)	Accounted for confounders?	Newcastle–Ottawa scale quality score
Masuda 198815	>80% community deaths, age >40 years, Japan	?	?	×	D, L, IT	?	O	?	×	6
Ishihara 199131	Selected hospital autopsies, Japan	S	?	×	D+IT, D+L, L	72	IS, O	75	×	4
Ng 199129	Consecutive hospital autopsies, age >40 years, Hong Kong	S	✓	×	?	?	?	?	×	5
Cartier 199932	Selected hospital autopsies, Chile	S	✓	×	L, IT, BG	65	O	64	Age	5
Mastaglia 200334	Consecutive hospital autopsies, mean age 75 years, Australia	S	?	×	C, EC, L,	?	IS, ?	?	×	4
Xu 200330	Hospital autopsies, mean age 78 years, China	S	?	×	?	?	?, D	?	×	4
Badhe 200533	Randomly selected autopsies, aged >70 years, India	S	✓	×	?	?	IS, O	?	×	4
Ritter 200514	Selected consecutive hypertensive hospital autopsies, Hungary	S	✓	✓	D+IT, L	69	IS, O	73	Age	8
Attems 200835	Consecutive hospital autopsies, Austria	S	?	×	D, H, L, IT	62–96	?, D	?	×	5
Guidoux 200836	Selected consecutive hospital autopsies, France	S	✓	×	D+B, L+C	76	?	77	Age	6

ICH location: BG, basal ganglia; C, cerebellum; D, deep (basal ganglia/thalamus); D+B, deep includes brainstem; D+L, involving both deep and lobar locations; D+IT, deep includes infratentorial; EC, external capsule; H, hemispheric; IT, infratentorial (cerebellum or brain stem); L, lobar; L+C, lobar includes cerebellum.
Control type: D, dementia (diagnosed according to either clinical or pathological criteria); IS, ischaemic stroke; O, other.
✓, criterion met; ×, criterion not met; ?, unknown.
ICH, intracerebral haemorrhage.