CSF NFL also correlates with the score of the Clinical Dementia Rating Scale—Sum of Boxes (CDR-SB) in FTD as a whole and in the three subclasses bvFTD, nfvPPA, and svPPA, as well as, in bvFTD, with the score of the modified version of the CDR for FTD (CDR-FTD-SB) (Scherling et al., 2014; Ljubenkov et al., 2018). Here, NEFL is linked to frontotemporal dementia.