Table 3.

Meta-regression analysis.

Factor		Coeff.	P	RDOR	95%CI
Study design
	Prospective vs. Retrospective	0.5861	0.6703	1.31	0.26–6.66
Country
	Europe vs. Others	−0.305	0.5559	0.74	0.20–2.75
Enrollment
	Consecutive vs. Unreported	0.300	0.6687	1.35	0.22–8.19
Blind method
	Blind vs. Unreported	0.645	0.2847	0.52	0.12–2.24