Table 1.

Characteristics of included studies.

Author	Year	Country	Study design	Study population	Number (male/ female)	Age	BMI	Blood glucose	Insulin	HOMA-IR	Resistin	Correlation coefficient between resistin and IR	Correlation coefficient type	Blood sample
Al-Harithy and Al-Ghamdi (2005)	2005	Saudi	Cross sectional	44	0/44	45 ± 10	25.5 ± 4.9	8.74 ± 4.04 mmol/l	12.96 ± 5.15 μIU/mL	5.38 ± 6.63	19.42 ± 3.60 ng/ml	0.49	Pearson	Serum
Jung et al. (2005)	2005	Korean	RCTd	14	6/8	60 ± 8	23.3 ± 2.6	11.4 ± 2.1 mmol/l	85 ± 39 pmol/l	7.3 ± 3.3	2.49 ± 1.93 ng/ml	0.3	Pearson	Plasma
Jung et al. (2005)	2005	Korean	RCTd	13	6/7	54 ± 14	24.6 ± 2.4	10.3 ± 2.7 mmol/l	68 ± 20 pmol/l	5.3 ± 2.4	2.61 ± 1.69 ng/ml	0.1	Pearson	Plasma
Park et al. (2006)	2006	Japan	Cross sectional	104	53/51	53.8 ± 9.2	23.87c	≥7.0 mmol/l	–	2.241c	6.527 ng/mlc	0.157	Pearson	Serum
Mojiminiyi and Abdella (2007)	2007	Kuwaiti	Cross sectional	135	57/78	58.92c	31.21c	9.928 mmol/lc	21.239 μIU/mLc	8.964c	23.61 ng/mlc	0.3	Spearman	Plasma
Tokuyama et al. (2007)	2007	Japan	Cross sectional	113	77/36	55.8 ± 13.0	24.7 ± 3.88	149.1 ± 44.1 mg/dl	–	3.82 ± 5.16	10.35 ± 6.30 ng/ml	0.302	Spearman	Serum
Gharibeh et al. (2010)	2010	Jordan	Case control	140	63/77	54.36 ± 0.88	30.89 ± 0.47	10.10 ± 0.32 mmol/l	11.94 ± 0.60 μIU/mL	5.46 ± 0.37	7.82 ± 0.29 ng/ml	0.08505	Pearson	Plasma
Owecki et al. (2011)	2011	Poland	Cross sectional	136	61/75	48.8 ± 13.4	37.69 ± 7.22	5.49 ± 0.63 mmol/l	40.62 ± 54.04 μIU/mL	–	24.89 ± 9.73 ng/ml	−0.1608	Spearman	Serum
Stepien et al. (2011)	2011	Poland	Cross sectional	19	4/15	53.0 ± 13.19	33.19 ± 3.13	5.46 ± 0.50 mmol/l	6.10 ± 1.13 μIU/mL	1.47 ± 0.27	0.93 ± 0.42 ng/ml	−0.2000	Spearman	Serum
Stepien et al. (2011)	2011	Poland	Cross sectional	18	7/11	49.56 ± 14.16	34.77 ± 3.52	5.72 ± 0.52 mmol/l	14.29 ± 4.68 μIU/mL	3.64 ± 1.28	1.04 ± 0.44 ng/ml	0.1662	Spearman	Serum
Bu et al. (2012)	2012	China	Cross sectional	22	10/12	49.64c	22.75c	7.736 mmol/lc	7.345 μIU/mLc	2.013c	1.717 ng/mlc	−0.178	Pearson	Plasma
Yin et al. (2012)	2012	China	Case control	38	18/20	45 ± 10	25.5 ± 4.9	7.4 ± 1.7 mmol/l	9.2 ± 6.2 mIU/l	5.5c	12.3 ± 2.7 ng/ml	0.09	Pearson	Serum
Mabrouk et al. (2013)	2013	Egypt	Case control	24	8/16	32.4 ± 9	53.7 ± 5.43	161.8 ± 23.9 mg/dl	17.7 ± 1.8 μIU/mL	5.4 ± 0.65	51 ± 8.2 ng/ml	0.56	Pearson	Serum
Stepien et al. (2014)	2014	Poland	Cross sectional	16	4/12	59.3 ± 13.4a	34.5 ± 3.0a	5.1 ± 0.4 mmol/la	7.5 ± 2.3 μIU/mLa	1.7 ± 0.5a	1.0 ± 0.4 ng/mla	0.013	Pearson	Serum
Stepien et al. (2014)	2014	Poland	Cross sectional	48	20/28	54.8 ± 11.2	36.8 ± 4.9	5.9 ± 0.4 mmol/l	17.2 ± 8.3 μIU/mL	4.5 ± 2.3	1.0 ± 0.3 ng/ml	−0.223	Pearson	Serum
Zaidi and Shirwany (2015)	2015	Pakistan	Cross sectional	40	12/28	44 ± 7	35 ± 5	164 ± 46 mg/dl	37 ± 7 μIU/mL	19 ± 8	38 ± 8 ng/ml	0.561	Pearson	Serum
Zaidi and Shirwany (2015)	2015	Pakistan	Cross sectional	40	12/28	40 ± 6	33 ± 3	83 ± 8 mg/dl	26 ± 6 μIU/mL	5 ± 1	25 ± 5 ng/ml	0.307	Pearson	Serum
Kaplon-Cieslicka et al. (2015)	2015	Poland	Cross sectional	119	69/50	70b	30.4b	–	–	3.6b	7.1 ng/mlb	0.03	Spearman	Serum
Kaplon-Cieslicka et al. (2015)	2015	Poland	Cross sectional	76	29/47	66b	30.6b	–	–	4b	6.4 ng/mlb			Serum
Parreno Caparros et al. (2017)	2017	Spain	RCTd	68	22/46	39.57 ± 10.15	48.27 ± 7	114.65 ± 42.96 mg/dl	24.21 ± 15.47 mIU/l	7.39 ± 6.64	9.42 ± 3.81 ng/ml	0.201	Pearson	Plasma

Data was presented by mean ± SD.

^aData presented by mean ± SEM.

^bData presented by median.

^cData presented by mean.

^dData was collected from the baseline.