Fig. 4

Cumulative sensitivity relative to the degree of simulated atrophy (across vertices/brain regions), comparison between the four tested methods. All methods detected atrophy more sensitive for more pronounced degrees of atrophy. However, the degree of atrophy the methods required to reach a given level of sensitivity differed. For example, in the current simulation, in order to detect atrophy in 80% of cases (black horizontal dashed line), method 4 (“z-score: per label”, purple line) required only 12% atrophy, method 3 (“z-min: per label”, golden line) 23%, method 2 (“z-min: per data point, averaged across labels”, blue line) 88%, while method 1 (“z-min: per data point”, red line) failed to detect atrophy in 80% of cases even for the highest possible degree of atrophy (100%). Compare also Table 2 for a summary of these results