NEFL and Parkinson disease: To determine whether the addition of CSF or serum NfL to alpha-synuclein contributes to the diagnosis of PD, Oosterveld et al. (2020) combined CSF neurofilament, phosphorylated−/total alpha-synuclein, and oligomeric−/total alpha-synuclein to obtain the CSF biomarker battery, which was considered as the best biomarker model to differentiate PD patients from healthy individuals.