Appendix Table 2.

Assessing the Quality of Included Studies Using 15 Criteria

Study, Year (Reference)	AF Was the Primary Exposure of Interest (Score of 0/1)	Assessment Temporality (Score of 0/1)	Imaging/Autopsy for the Purpose of Research (Score of 0/1)	ECG Documentation of AF (Score of 0/1)	CAS Assessed/Reported (Score of 0/1)	Inclusion and Exclusion Criteria Clearly Stated (Score of 0/1)	Risk of Confounding Bias (Score of 0/1/2)	Diagnosis Method (Score of 1/2/3)	Attempted to Distinguish SCI From Leukoaraiosis in MRI Studies? (Score of 0/1/2/3)			Attempted to Distinguish SCI From EPVS (Score of 0/1)	Blinding to Clinical Data (Score of 0/1)	Assessment of Radiology or Autopsy Reports by >1 Person (Score of 0/1)	History of Stroke Confirmed by Neurologic Examination (Score of 0/1)	Total Quality Score Met, %
									Did Authors Acknowledge the Exclusion of Leukoaraiosis From the Final Analysis? (Score of 0/1)	Was DWI Used to Distinguish SCIs From Leukoaraiosis? (Score of 0/1)	Was Nonterritorial FLAIR Hyperdensity or Marked T1 Hypodensity Used as an Additional Criterion to Identify SCI? (Score of 0/1)
Shinkawa et al, 1995 (15)	No	Cross-sectional	Yes	Yes	No	Yes	Minimal	Autopsy	NA	NA	NA	Yes	–	–	–	53.8
Yamanouchi et al, 1997 (16)	Yes	Cross-sectional	Yes	Yes	No	Yes	Minimal	Autopsy	NA	NA	NA	Yes	–	Yes	–	69.2
Petersen et al, 1989 (19)	Yes	Cross-sectional	Yes	Yes	No	Yes	Moderate	CT	NA	NA	NA	No	Yes	Yes	Yes	71.4
Petersen et al, 1989 (32)	Yes	Cross-sectional	Yes	Yes	No	Yes	Moderate	CT	NA	NA	NA	No	Yes	Yes	Yes	71.4
Feinberg et al, 1990 (17)	Yes	Cross-sectional	Yes	Yes	No	Yes	N/A	CT	NA	NA	NA	No	Yes	Yes	–	66.7
Guidotti et al, 1990 (18)	Yes	Cross-sectional	No	Yes	Yes*	Yes	Minimal	CT	NA	NA	NA	No	Yes	No	Yes	71.4
Ezekowitz et al 1995 (33)	Yes	Both	Yes	Yes	Yes†	Yes	NA	CT	NA	NA	NA	No	Yes	Yes	Yes	91.7
Zito et al, 1996 (34)	Yes	Cross-sectional	Yes	Yes	Yes‡	Yes	Minimal	CT	NA	NA	NA	No	Yes	Yes	–	78.6
Hara et al, 1995 (35)	Yes	Cross-sectional	Yes	Yes	No	Yes	NA	MRI	No	No	–§	Yes	Yes	No	–	56.3
Longstreth et al, 2002 (14)	No	Both	Yes	Yes	Yes‖	Yes	Unknown	MRI 1.5T or 0.35T	Yes	No	Yes	Yes	Yes	Yes¶	Yes¶	77.8
Vermeer et al, 2003 (23)	No	Cross-sectional	Yes	Yes	No	Yes	Moderate	MRI 1.5T	Yes	No	Yes	Yes	–	No	No	55.6
Strach et al, 2005 (29)	Yes	Both	Yes	Yes	No	Yes	NA	MRI 1.5T	No	Yes	Yes	Yes	Yes	Yes	Yes	87.5
Das et al, 2008 (11)	No	Cross-sectional	Yes	Yes	Yes**	Yes	Moderate	MRI 1T	Yes	No	No	Yes	Yes	Yes	Yes	72.2
Kim et al, 2011 (13)	No	Cross-sectional	Yes	Yes	No	Yes	Minimal	MRI 1.5T	Yes	No	No	Yes	Yes	Yes	Yes	72.2
Kobayashi et al, 2012 (36)	Yes	Cross-sectional	Yes	–	Yes††	Yes	Minimal	MRI 1.5T	Yes	No	No	Yes	Yes	Yes	–	72.2
Marfella et al, 2013 (12)	Yes	Cross-sectional	Yes	Yes	Yes‡‡	Yes	Minimal	MRI 1.5T	Yes	No	Yes	No	Yes	–	–	72.2
Saito et al, 2014 (37)	Yes	Cross-sectional	Yes	–	No	Yes	High	MRI 1.5T	No	No	Yes	Yes	Yes	–	–	50.0

AF = atrial fibrillation; CAS = carotid artery stenosis; CT = computed tomography; DWI = diffusion-weighted imaging; ECG = electrocardiography; EPVS = enlarged perivascular space; FLAIR = fluid-attenuated inversion recovery; MRI = magnetic resonance imaging; NA= not applicable; SCI = silent cerebral infarction.

^*AF = 16.6%, and SR = 11.1% (no significant difference between groups).

^†Stenosis ≥75%; SCI = 5%; and no SCI = 4% (no significant difference between groups; P = 0.67).

^‡Excluded stenosis >50%.

^§Only assessed cortical infarctions.

^‖Maximum internal carotid artery stenosis was not a predictor of incidental infarction.

^¶From reference 20.

^**15% had carotid artery stenosis ≥25%.

^††No significant difference in maximum intima–media thickness between nonvalvular atrial fibrillation and control patients.

^‡‡Patients with carotid disease were excluded.