University of Tokyo - School of Public Health, University of Tokyo - Graduate School of Economics, University of Tokyo - School of Public Health, University of Tokyo - Institute of Gerontology, University of Tokyo - Institute of Gerontology, University of Tokyo - Institute of Gerontology, University of Tokyo - Institute of Industrial Science, University of Tokyo - Institute of Industrial Science, Stanford University - Walter H. Shorenstein Asia-Pacific Research Center (APARC), Stanford University - Center for Primary Care and Outcomes Research and University of Tokyo - School of Public Health