Table 3. Subgroup analysis of study region and detection method.

Subgroup		No. of Trials	No. of Patients	Sensitivity	Specificity
Region	Europe	21	7243	0.740 (95%CI: 0.676- 0.795)	0.932 (95%CI: 0.904-0.953)
	Asia	14	2303	0.590 (95%CI: 0.496- 0.678)	0.901 (95%CI: 0.819-0.948)
Detection method	ELISA	15	3498	0.722 (95%CI: 0.623- 0.803)	0.910 (95%CI: 0.858- 0.944)
	RIA	14	3838	0.655 (95%CI: 0.545- 0.751)	0.949 (95%CI: 0.904- 0.973)
	ECISA	6	2210	0.674 (95%CI: 0.584- 0.753)	0.869 (95%CI: 0.766- 0.931)
Europe	ELISA	8	2541	0.792 (95%CI: 0.617- 0.900)	0.922 (95%CI: 0.866-0.955)
	RIA	10	3073	0.720 (95%CI: 0.632- 0.794)	0.936 (95%CI: 0.882-0.966)
	ECISA	3	1629	0.673(95%CI: 0.633- 0.712)	0.922 (95%CI: 0.904-0.937)
Asia	ELISA	7	957	0.653 (95%CI: 0.543- 0.750)	0.886 (95%CI: 0.783- 0.944)
	RIA	4	765	0.655 (95%CI: 0.299- 0.532)	0.970 (95%CI: 0.870- 0.994)
	ECISA	3	581	0.630 (95%CI: 0.523- 0.729)	0.736 (95%CI: 0.695- 0.775)

ELISA: enzyme linked immunosorbent assay; ECSIA: electro- chemiluminescence immunoassay; RIA= radioimmunoassay assay.