Table 3. Characteristics of size and composition of urinary stones in the patients.

Items	Studies	Number of patients	Heterogeneity		Overall effect
		BMI<25 vs BMI≥25 (kg/m2)	p value	I2 (%)	RR/WMD (95% CI)	p value*
size of urolithiasis	[14, 20, 26, 29]	618/406	0.64	0	-0.13(-0.98, 0.73)	0.77
calcium oxalate	[19, 21, 22, 24, 25, 27, 28, 30-32]	4103/3831	<0.00001	96%	0.95(0.91, 0.98)	0.006
calcium oxalate (male)	[22, 25, 27]	970/728	0.8	0%	1.34(1.05, 1.72)	0.02
calcium oxalate (female)	[22, 25, 27]	484/337	0.32	13%	1.16(0.85, 1.58)	0.36
calcium phosphate	[21, 22, 24, 25, 27, 28, 30-32]	3264/3292	<0.00001	91%	1.15(0.97, 1.35)	0.1
calcium phosphate(male)	[22, 25, 27]	970/728	0.82	0%	1.52(1.06, 2.17)	0.02
calcium phosphate(female)	[22, 25, 27]	484/337	0.76	0%	1.19(0.90, 1.58)	0.22
uric acid	[19, 21, 22, 23, 24, 25, 27, 28, 30-32]	5519/4879	0.00001	98%	0.87(0.83, 0.91)	<0.00001
uric acid (male)	[22, 25, 27]	970/728	0.66	0%	0.48(0.36, 0.64)	<0.00001
uric acid (female)	[22, 25, 27]	484/337	0.72	0%	0.47(0.29, 0.76)	0.002
carbapatite	[19, 27, 32]	1032/1104	0.52	0%	1.09(0.85, 1.40)	0.51
cystin	[27, 32]	193/565	0.02	81%	2.52(1.20, 5.31)	0.01
mixed stones	[19, 24, 25, 27, 31]	1751/2316	0.36	9%	1.15(1.06, 1.24)	0.00009
mixed stones (male)	[25, 27]	86/242	0.79	0%	1.04(0.68, 1.57)	0.87
mixed stones (female)	[25, 27]	109/151	0.07	69%	1.05(0.77, 1.43)	0.74

*p <0.05 was considered statistically significant and shown in bold.