FIGURE 1. Agreement between the test and retest conditions for measuring the mean ratio of specific-striatal-to-nonspecific uptake ([striatum - occipital cortex]/occipital cortex). The line of identity (Y = X) emerging from the origin (0,0) indicates complete agreement between the 2 conditions. The dashed lines represent 95% confidence curves. The 95% CI for the observed correlation of 0.91 is 0.78–0.97.