Table 3.

Meta-analysis of the 15 studies^* stratified by their geographic origin

Detection method	No. of studies	Events	Sample size	Point estimates of event rates (fixed effects model)		Point estimates of event rates (random effects model)		Homogeneity (Cochran's Q)**	I-squared (I2)**	Homogeneity(p-value)**
				Point estimate	95% CI	Point estimate	95% CI
Other Asia	3	4	6	0.631	0.229–0.908	0.631	0.173–0.933	2.878	30.510	0.237
Europe	5	20	56	0.356	0.226–0.513	0.411	0.127–0.770	10.989	63.601	0.027
North America	7	14	27	0.486	0.297–0.678	0.517	0.297–0.730	6.808	11.867	0.339
Summary	15	38	89	0.422	0.311–0.542	0.507	0.328–0.685	22.690	38.300	0.065
Total within (FE)								20.675		0.055
Total between (FE)								2.015		0.365
Total between (RE)								0.467		0.792

^*All studies reporting only bronchial carcinomas are omitted

^**Only calculated for fixed effects modelFE – fixed effects, RE – random effects

FE – fixed effects, RE – random effects