A Systematic Review and Meta-Analysis of the Relationship between Receiving the Flu Vaccine with Acute Cerebrovascular Accident and Its Hospitalization in the Elderly

Table 1

Characteristics of meta-analysis studies to investigate the relationship between receiving the flu vaccine and the risk of stroke and its hospitalization in the elderly.

Publication first author	Year	Study setting	Study design	Sample size	OR	95 % CI	Follow-up time (month)	Quality assessment
Lin [43]	2014	Taiwan	Case-control study	3120	0.8	(0.64–0.98)	36	6.5
Nichol [30]	2003	USA	Cohort	146328	0.77	(0.66–0.89)	24	8
Vamos [45]	2016	England	Cohort	124503	0.82	(0.67–1)	84	5.5
Hung [41]	2010	Hong Kong	Cohort	36636	0.67	(0.54–0.83)	12	6
Chang [46]	2020	Taiwan	Cohort	2741403	0.88	(0.83–0.94)	24	9
Ohmit [37]	1995	USA	Case-control study	4487	1.17	(0.73–1.88)	24	7.5
Pinol-Ripoll [40]	2008	Spain	Case-control	786	1.02	(0.77–1.36)	12	7
Grau [31]	2005	German	Case-control	740	0.46	(0.28–0.77)	24	6.5
Lavallee P [29]	2002	France	Case-control	689	0.37	(0.15–0.87)	60	6.5
Smeeth [24]	2004	UK	Nested case-control	23188	0.86	(0.76–0.97)	48	7
Lavallee PC [42]	2014	International	Prospective cohort	22837	1.01	(0.88–1.17)	48	8
Wang [38]	2004	Taiwan	Cohort	21347	0.96	(0.79–1.17)	6	7.5
Puig-Barbera J [39]	2007	Spain	Case-control study	380	0.07	(0.01–0.48)	12	8
Siriwardena [44]	2014	UK	Case-control study	72202	0.8	(0.76–0.84)	12	7.5