Table 3.

Association between OS and MTHFR C677T polymorphism in GC patients treated with 5-Fu based chemotherapy stratified by ways of presenting results, patients' ethnicities or chemotherapy purpose.

Subgroups	Number of Studies	Test of heterogeneity		Test of Association
		p	I2	HR	95%CI	Z	p
Ways of presenting results
CT/TT: CC	4	0.21	34%	0.92	[0.66,1.28]	0.49	0.62
TT: CC	3	0.78	0%	0.85	[0.60,1.20]	0.92	0.36
CT:CC	3	0.19	40%	1.10	[0.77,1.57]	0.51	0.61
Ethnicities
Asian	4	0.21	34%	0.92	[0.66,1.28]	0.49	0.62
European	2	0.64	0%	1.19	[0.90,1.58]	1.20	0.23
Chemotherapy Purpose
Palliative	2	0.38	0%	1.04	[0.67,1.61]	0.17	0.86
Perioperative	4	0.14	45%	1.03	[0.76,1.38]	0.17	0.86