Department of Neurology Qilu Hospital Cheeloo College of Medicine Shandong University Jinan 250012 Shandong Province ChinaDepartment of Gerontology Zibo Central Hospital Zibo 255036 Shandong Province China;
Department of Ophthalmology Zibo Central Hospital Zibo 255036 Shandong Province China;
Department of Gerontology Jinan Central Hospital Cheeloo College of Medicine Shandong University Jinan 250013 Shandong Province China;
Department of Neurology Jinan Central Hospital Affiliated to Shandong University Jinan 250013 Shandong Province China;
Department of Neurology Yantaishan Hospital Yantai 264001 Shandong Province China;
Department of Neurology Qilu Hospital Cheeloo College of Medicine Shandong University Jinan 250012 Shandong Province China;
Department of Neurology Qilu Hospital Cheeloo College of Medicine Shandong University Jinan 250012 Shandong Province China;
Multiple system atrophy; Parkinson’s disease; Serum growth differentiation factor 15; Biomarker ; Receiver-operating characteristic curve; Neurodegenerative disease;