About the Authors

Koji Iihara

kiihara@ns.med.kyushu-u.ac.jp

Affiliation Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan

Kunihiro Nishimura

Affiliation Department of Preventive Medicine and Epidemiologic Informatics, National Cerebral and Cardiovascular Center, Suita, Japan

Akiko Kada

Affiliation Clinical Research Center, National Hospital Organization, Nagoya Medical Center, Nagoya, Japan

Jyoji Nakagawara

Affiliation Integrative Stroke Imaging Center, National Cerebral and Cardiovascular Center, Suita, Japan

Kuniaki Ogasawara

Affiliation Department of Neurosurgery, Iwate Medical University, Morioka, Japan

Junichi Ono

Affiliation Chiba Cardiovascular Center, Ichihara, Japan

Yoshiaki Shiokawa

Affiliation Department of Neurosurgery, Kyorin University, Mitaka, Japan

Toru Aruga

Affiliation Showa University Hospital, Tokyo, Japan

Shigeru Miyachi

Affiliation Department of Neurosurgery, Nagoya University, Nagoya, Japan

Izumi Nagata

Affiliation Department of Neurosurgery, Nagasaki University, Nagasaki, Japan

Kazunori Toyoda

Affiliation Department of Cerebrovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan

Shinya Matsuda

Affiliation Department of Preventive Medicine and Community Health, University of Occupational and Environmental Health, Kita-Kyushu, Japan

Yoshihiro Miyamoto

Affiliation Department of Preventive Medicine and Epidemiologic Informatics, National Cerebral and Cardiovascular Center, Suita, Japan

Akifumi Suzuki

Affiliation Research Institute for Brain and Blood Vessels, Akita, Japan

Koichi B. Ishikawa

Affiliation Center for Cancer Control and Information Services, National Cancer Center, Tokyo, Japan

Hiroharu Kataoka

Affiliation Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan

Fumiaki Nakamura

Affiliation Department of Public Health, The University of Tokyo, Tokyo, Japan

Satoru Kamitani

Affiliation Department of Public Health, The University of Tokyo, Tokyo, Japan

Competing Interests

Ube Industries, Ltd., Central Hospital participated in this study by providing survey data. This does not alter the authors' adherence to PLOS ONE Editorial policies and criteria.

Author Contributions

Conceived and designed the experiments: KI KN AK. Analyzed the data: KI KN AK. Wrote the paper: KI KN AK. Collection of data: JN KO JO YS TA S. Miyachi IN KT S. Matsuda YM AS KBI HK FN SK.