Table 4. Sensitivity analysis.

Items	Studies	Number of patients	Heterogeneity		Overall effect		Higher in
		BMI<25 vs BMI≥25 (kg/m2)	p value	I2 (%)	RR/WMD (95% CI)	p value*
size of urinary stones	14, 20, 26]	546/394	0.45	0	-0.15(-1.01, 0.72)	0.74	/
calcium oxalate	[19, 21, 22, 24, 25, 27, 28, 30, 32]	3867/3427	<0.00001	97%	0.95(0.91, 0.99)	0.01	BMI ≥25
calcium phosphate	[21, 22, 24, 25, 27, 28, 30, 32]	3028/2888	<0.00001	91%	0.98(0.85, 1.14)	0.83	/
uric acid	[19, 21, 22, 23, 24, 25, 27, 28, 30, 32]	5283/4475	0.00001	98%	0.89(0.86, 0.93)	<0.00001	BMI ≥25
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	BMI <25
mixed stones	[19, 24, 25, 27]	1515/1912	0.63	0%	1.20(1.08, 1.34)	0.001	BMI <25

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