Role of neutrophil to lymphocyte ratio in osteoarthritis: A systematic review and meta-analysis

Table 1 General characteristics of included studies

Ref.	Country	Design	Age	Male, %	BMI	Healthy control, n, NLR	OA, total, n, NLR	Mild-moderate OA, n, NLR	Severe OA, n, NLR	NOS score
Taşoğlu et al[10], 2016	Turkey	Retrospective	61.75	78.4	33.07	NR	NR	146, 1.79 ± 0.80	30, 2.18 ± 1.04	7
Atar et al[14], 2017	Turkey	Retrospective	56.21	88	28.36	57, 1.76 ± 0.66	92, 2.02 ± 0.75	44, 2.11 ± 0.79	48, 1.93 ± 0.70	6
Hira and Tamam[18], 2017	Turkey	Retrospective	50	64	NR	145, 1.79 ± 0.97	118, 2.15 ± 1.12	NR	NR	8
Büyükavcı et al[16], 2018	Turkey	Retrospective	63.5	70.5	27.04	NR	NR	165, 1.91 ± 0.82	69, 2.16 ± 0.84	8
Gundogdu et al[7], 2018	Turkey	Prospective	61.75	83	32.78	30, 2.25 ± 0.91	60, 2.37 ± 1.67	NR	NR	6
Özler et al[21], 2018	Turkey	Retrospective	59.55	NR	NR	NR	NR	112, 2.04 ± 0.08	106, 2.40 ± 0.14	7
Gao et al[17], 2019	China	Retrospective	55.47	51.66	NR	120, 1.49 ± 0.40	119, 2.39 ± 1.73	86, 2.22 ± 1.59	33, 2.85 ± 2.00	6
Koca et al[20], 2019	Turkey	Retrospective	59.06	82.29	NR	NR	NR	105, 2.10 ± 1.50	104, 2.90 ± 2.40	7
Cai et al[8], 2021	China	Prospective	59.4	75.35	23.15	150, 1.42 ± 0.62	142, 2.81 ± 1.14	NR	NR	8
Karataş et al[19], 2021	Turkey	Retrospective	52.67	84.7	27.74	40, 2.45 ± 2.60	122, 2.33 ± 0.74	70, 2.08 ± 1.92	52, 2.40 ± 1.09	7
Al-Janaby[13], 2021	Iraq	Prospective	60.4	65	29.1	50, 1.97 ± 0.88	100, 2.19 ± 0.72	NR	NR	7
Bakılan et al[15], 2022	Turkey	Retrospective	60.85	92	NR	NR	NR	81, 1.81 ± 0.67	55, 1.94 ± 0.80	6
Korkmaz et al[24], 2022	Turkey	Prospective	57.6	23.7	NR	59, 1.7 ± 0.7	76, 2.1 ± 1.3	37, 2.1 ± 1.5	39, 2.1 ± 0.9	7
Yasar et al[22], 2022	Turkey	Retrospective	65.7	36	NR	NR	NR	35, 2.11 ± 0.9	30, 1.82 ± 0.7	7
Ünal Enginar et al[23], 2023	Turkey	Retrospective	65	100	NR	50, 1.7 ± 0.45	50, 1.60 ± 0.53	43, 1.60 ± 0.53	7, 1.66 ± 1.10	8

Some studies did not report all variables, such as body mass index or age. The neutrophil to lymphocyte ratio value is expressed as mean ± SD. BMI: Body mass index; NR: Not reported; NLR: Neutrophil to lymphocyte ratio; NOS: Newcastle-Ottawa scale; OA: Osteoarthritis.