Bovine Leukemia virus (BLV) and risk of breast cancer: a systematic review and meta-analysis of case-control studies

Table 1 Characteristics of studies included in the current study

study	Publication year	Sample collection date	country	continent	Study-design	Sample type	Detection target	Case	Case positive	Control	Control positive	Detection method	Age control	Age case	NOS score	ref
Giovanna	2013	Since 2006	Colombia	South America	Case–control	FFPE	Gag	53	19	53	24	PCR	52.2	46.4	8	[14]
Schwingel	2019	2015–2017	Brazil	South America	Case–control	FFPE	Tax	72	22	72	10	Nested PCR	38	52.5	9	[15]
Buehring	2007	NR	US	North America	Case–control	FFPE	Tax	110	65	103	30	In situ PCR	NR	NR	9	[16]
Buehring	2015	2002–2008	US	North America	Case–control	FFPE	Tax	114	67	104	30	In situ PCR	48.7	55.9	9	[17]
Baltzell	2017	2009–2011	US	North America	Case–control	FFPE	Tax	61	35	103	20	In situ PCR	54.4	54.59	9	[18]
Buehring	2017	1995–2010	Australia	ocenia	Case–control	FFPE	Tax	50	40	46	19	In situ PCR	49.59	55.08	9	[12]
Lawson and Glenn	2017	NR	Australia	ocenia	Case–control	FFPE	Tax	22	20	17	6	In situ PCR	36.4	56.1	8	[19]
Khalilian	2019	2017–2018	Iran	Middle East	Case–control	FFPE and Blood	Tax	172	52	200	60	In situ PCR	47.5	53	9	[11]
Khalilian	2019	2017–2018	Iran	Middle east	Case–control	FFPE and Blood	Gag	172	14	200	16	Nested PCR	47.5	53	8	[11]

FFPE Formalin-fixed paraffin-embedded, PCR Polymerase chain reaction, NOS Newcastle- Ottawa assessment scale

ISSN: 1750-9378