Numbers of subjects with normal and abnormal classified CSF marker values based on predefined cut-offs.

Results are the percentage (number) of subjects with normal and abnormal classified CSF markers based on CSF analysis 1 (routine practice) and analysis 2 (LeARN study). The CSF AD profile was defined as abnormal Aβ1-42 and abnormal t-tau or p-tau, based on predefined cut-offs (see methods).CSF = cerebrospinal fluid, Aβ = amyloid beta, t-tau = total tau, p-tau = phosphorylated tau.*The routine analyses in Nijmegen and the LeARN analyses were dichotomized according to the Amsterdam cut-offs (see methods).**The routine analyses in Nijmegen were dichotomized according to the Nijmegen cut-offs and the LeARN analyses according to the Amsterdam cut-offs (see methods).