[Retracted] Relationship between Platelet-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio with Spontaneous Preterm Birth: A Systematic Review and Meta-analysis

Table 1

The included studies and their attributes.

Study, year	Country	Duration	Study design	Sample size (T/C)	Age (T/C)	Parameters	CBC test
Daglar et al., 2016 [28]	Turkey	2011-2012	Prospective case control	30/53	/	PLR, LMR	Upon admission
Gezer et al., 2018 [29]	Turkey	2010-2015	Retrospective case control	229/178	/	PLR	Upon admission
Jaffar and Feissal Rabie, 2018 [30]	Egypt	During 2017	Retrospective case control	439/200	/	PLR	Not reported
Chen et al., 2019 [31]	China	2016-2017	Retrospective case control	100/116	Not reported	PLR, LMR	28-30 weeks of pregnancy
Ozel et al., 2019 [32]	Turkey	2016-2017	Retrospective case control	110/47	/	PLR	Upon admission
Cha et al., 2020 [33]	Korea	2015-2017	Prospective case control	28/308	/	PLR, LMR	24-28 weeks of pregnancy
Ma et al., 2020 [34]	China	During 2017	Retrospective case control	105/210	/	PLR, LMR	20-30 weeks of pregnancy
Wu et al., 2020 [35]	China	During 2019	Retrospective case control	34/80	/	PLR, LMR	Upon admission
Mi and Sun, 2021 [36]	China	2017-2020	Retrospective case control	40/30	/	PLR	Upon admission