Figure 3: Modification of the probabilities shown in Figure 2 due to the effect of correlation in the observed single-reader cancer detection rates between two arms of a trial. The correlation was measured from two separate studies of screening mammography (see Statistical Analyses section). The Pearson correlation coefficient was 0.44. Shaded areas represent 95% confidence intervals. The confidence band with the effect of correlation taken into account (not shown) was 2%–4% wider than the corresponding confidence band without correlation.