1Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351 Korea
2Neuroscience Center, Samsung Medical Center, 06351 Seoul, Korea
3Center for Clinical Epidemiology, Samsung Medical Center, 06351 Seoul, Korea
4Health Promotion Center, Samsung Medical Center, 06351 Seoul, Korea
5Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, Korea
6Department of Neurology, Kyung Hee University Hospital, Seoul, Korea
7Department of Neurology, Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
8Department of Health Sciences and Technology, Sungkyunkwan University, Seoul, 06351 Korea
9Clinical Research Design and Evaluation, SAIHST, Sungkyunkwan University, Seoul, 06351 Korea
10Department of Epidemiology, Johns Hopkins Medical Institutions, Baltimore, USA
11Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, USA
12Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Medical Institutions, Baltimore, USA
© The Author(s) 2019
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