Table 3.

NOS study assessment.

Study	Marker	S1	S2	S3	S4	C1	O1	O2	O3	Total
Bambury 2013 [45]	NLR	*	*	*	0	*	*	*	*	7
Han 2015 [46]	NLR	*	*	*	0	**	*	*	*	8
Lopes 2018 [47]	NLR	*	*	*	0	*	*	*	*	7
Weng 2018 [19]	NLR	*	*	*	0	*	*	*	*	7
Yersal 2018 [48]	NLR, PLR	*	*	*	0	**	*	*	*	8
Brenner 2019 [49]	NLR	*	*	*	0	**	*	*	*	8
Hao 2019 [50]	NLR, PLR	*	*	*	0	**	*	*	*	8
Gan 2019 [51]	NLR	*	*	*	0	*	*	*	*	7
Lv 2019 [14]	NLR, PLR, SII	*	*	*	0	**	*	*	*	8
Bagley 2020 [52]	cfDNA	*	*	*	0	*	*	*	*	7
Marini 2020 [53]	NLR, PLR	*	*	*	0	**	*	*	*	8
Mermut 2020 [54]	NLR	*	*	*	0	**	*	*	*	8
Bagley 2021 [55]	cfDNA	*	*	*	0	*	*	*	*	7
Besiroglu 2021 [56]	NLR, PLR, SII	*	*	*	0	*	*	*	*	7
Clavreul 2021 [57]	NLR, PLR, SII, SIRI	*	*	*	0	**	*	*	*	8
Garrett 2021 [58]	NLR	*	*	*	0	*	*	*	*	7
Jarmuzek 2022 [7]	NLR, SII, SIRI	*	*	*	0	**	*	*	*	8
Pasqualetti 2022 [59]	PLR, SII	*	*	*	0	**	*	*	*	8
Shi 2022 [12]	NLR, PLR, SII, SIRI	*	*	*	0	**	*	*	*	8
Wang 2022 [60]	NLR, SIRI	*	*	*	0	**	*	*	*	8
Yang 2022 [61]	NLR, PLR	*	*	*	0	**	*	*	*	8

Abbreviations: Selection (max *), S1 representativeness of the exposed cohort, S2 selection of the non-exposed cohort, S3 ascertainment of exposure, S4 demonstration that outcome of interest was not present at start of study. Comparability (max **), C1 comparability of cohorts based on the design or analysis. Outcome (max *), O1 assessment of outcome, O2 follow-up long enough for outcomes to occur, O3 adequacy of follow-up of cohorts, NLR neutrophil-to-lymphocyte ratio, PLR platelet-to-lymphocyte ratio, SII systemic immune inflammation index, SIRI systemic inflammation response index, cfDNA cell-free DNA.