1. Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province 050000, China
2. Department of Neurology, North China University of Science and Technology Affiliated Hospital, North China University of Science and Technology, Tangshan, Hebei Province 063000, China
3. Department of Radiotherapy and Chemotherapy, Tangshan People's Hospital, Tangshan, Hebei Province 063000, China
4. Department of Statistics, Hebei Medical University, Shijiazhuang, Hebei Province 050000, China