Figure 1
From: Deficits in plasma oestradiol measurement in studies and management of breast cancer
Relative risk (RR) of breast cancer by increasing quintiles of oestradiol concentration from a pooled analysis of nine studies (modified from [3]). The position of each square indicates the magnitude of the RR, and the area of the square is proportional to the amount of statistical information available. The length of the horizontal line through the square indicates the 95% confidence interval (CI).