NEFL and Alzheimer disease: Several CSF biomarkers for AD, including amyloid-β42 (Aβ42), Aβ42/40, phospho-tau181 (P-tau181), neurogranin concentration, and neurofilament light (NfL) concentration have been found (Jong et al., 2006; Mattsson et al., 2017; Spies et al., 2010; Yu et al., 2023; Zetterberg et al., 2016).