CTLA-4 and MDR1 polymorphisms increase the risk for ulcerative colitis: A meta-analysis

Table 3 Meta-regression analyses of potential source of heterogeneity

Heterogeneity factors	Coefficient	SE	t	P value	95%CI
				(adjusted)	LL	UL
Year	-0.061	0.035	-1.76	0.359	-0.15	0.028
Country	-0.054	0.03	-1.78	0.352	-0.131	0.024
Ethnicity	0.001	0.042	0.03	1	-0.106	0.109
Method	0.203	0.092	2.2	0.219	-0.034	0.44
SNP	0.045	0.057	0.79	0.85	-0.101	0.191
Sample	0	0	0.09	1	0	0

SE: Standard error; LL: Lower limit; UL: Upper limit. SNP: Single nucleotide polymorphism.