Appendix A4. Quality of Studies Assessing the Association Between Arg280His Polymorphism and Breast Cancer ^a,b.

Study (year)	Source of Control	Population Ethnicity	Sample Size	Menopausal Status	HWE Reported
Moullan (2003)	+	-	+	-	+
Chacko (2005)	+	-	+	+	+
Metsola (2005)	+	+	+	A	+
Pachkowski (2006)	+	+	+	-	+
Zhang (2006)	+	+	+	+	+
Smith (2008)	+	+	+	-	+
Loizidou (2008)	B	+	+	-	+
Sangrajrang (2008)	+	-	+	+	+
Zipprich (2010)	+	C	+	D	+
Liu (2011)	+	+	+	-	+

^a Definitions: Year, year of publication; Source of control means clinic (or hospital) based or population based; Population ethnicity means Caucasian, African-American and other ethnicity; Sample size means calculable sample size; Menopausal status means adjustment of menopausal status (post, pre or both) for final measure of association using methods such as adjustment in regression models, restriction, stratification etc; HWE (Hardy Weinberg equilibrium) means calculated or reported HWE equilibrium.

^b A, Calculated OR for different strata, but data not shown; B, Source of controls: volunteers; C, Matched controls, but no detail presented; D, Adjusted, but no detail presented.