Upper: the 31 local governments that participated in this survey are shown on the map of Fukushima Prefecture. Upper: the 31 local governments that participated in this survey are shown on the map of Fukushima Prefecture. Lower: the air radiation dose from March 2011 to December 2014 for each of the three areas is shown. ◆: Hamadori area, ■: Nakadori area, ▲: Aizu area. Atsushi Ono et al. bmjpo 2018;2:e000229 © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.