During ADNI-1,VISCODE was used as the visit code and corresponded to the timing of the visit. In ADNI-GO and ADNI-2, the visit codes changed to reflect the various types of visits and no longer included codes that were obviously linked to a particular timing of a visit. VISCODE2 is the variable that translates the other visit codes into visit codes more easily recognized (such as m48), so if you filter by VISCODE2=="bl", that should filter by baseline diagnosis.

how many participants(normal,MCI,AD) of WGS data after select baseline diagnosis only?


thanks