Table 3.

Subgroup analysis for the MTHFR C677T polymorphisms

	CT vs. CC		TT vs. CC		Pb	CT+TT vs. CC		Pb
	ORa	95%CI	ORa	95%CI		ORa	95%CI
Gender					0.90			0.96
Male	0.89	0.74-1.08	0.90	0.63-1.16		0.89	0.74-1.07
Female	0.91	0.72-1.16	0.85	0.63-1.16		0.90	0.72-1.12
Age					0.39			0.84
≤ 65	0.96	0.80-1.16	0.87	0.68-1.12		0.94	0.79-1.12
> 65	0.80	0.62-1.04	0.90	0.64-1.25		0.83	0.65-1.05
Smoking status					0.55			0.77
Never	0.90	0.72-1.12	0.80	0.60-1.07		0.87	0.71-1.08
Ever	0.89	0.73-1.10	0.97	0.73-1.28		0.91	0.75-1.11
Histological type					0.64			0.99
ADC	0.89	0.75-1.05	0.93	0.74-1.16		0.90	0.76-1.06
SQC	0.78	0.64-0.96	0.80	0.61-1.04		0.79	0.65-0.95
SCLC	0.96	0.75-1.22	0.83	0.59-1.15		0.92	0.73-1.17
Others	0.93	0.70-1.26	0.77	0.51-1.15		0.89	0.67-1.18

SCLC, small cell lung cancer; SQC, squamous cell carcinoma; ADC, adenocarcinoma; others, large cell carcinoma and mixed types.

OR^a: odds ratio adjusted for age and gender, CI, confidence interval;

P^b: p values for heterogeneity.