NEFL and Alzheimer disease: Serum and CSF measurements of NfL correlated in the disease groups (Figure 5a): AD (r=0.48, p=0.033), GBS (r=0.79, p<0.0001) and ALS (r=0.70, p<0.0001), conversely this was not seen in CP (r=0.11, p=0.3739) (Figure 5b).