Magnitude of practice effects: development of clinical classification over 1 year. Clinical classification of baseline performance shows that cognitive performance is distributed across all categories (below- to above-average percentile ranks, PR) despite a high-IQ sample of healthy individuals. In all depicted cognitive domains, score gains lead to better clinical classification over time (selected time-points months 3 and 12 presented) without reaching upper limits for most subjects. Only in visuospatial functions, the majority of subjects achieved highest scores already at baseline with only modest subsequent changes, altogether pointing to a ceiling effect. Clinical classifications of individual performance are based on test-specific normative data and averaged by cognitive domains. For executive functions, normative data of RWT phonemic verbal fluency is unavailable. Data on motor tests are not presented due to insufficient normative data.