The diagnostic performance for FTD was much better than for DLB in our study, due to NfL being a strong biomarker for the most common types of FTD as was also observed by others,55, 56 and because there is a lower prevalence of AD co‐pathology (in the current dataset: 17%) leading to higher specificity of especially P‐tau181 for AD.57 Here, NEFL is linked to Alzheimer disease.