CBS and Alzheimer disease: There was a long diagnostic delay for CBS-AD (mean [SD], 4.6 [3.2] years) and PSP-subcortical (mean [SD], 4.2 [3.2] years) groups compared with the CBS-4RT (mean [SD], 3.1 [4.7] years) and PSP-RS (mean [SD], 2.3 [1.8] years) groups.