About the Authors

Ryo Oizumi

oizumi@ms.u-tokyo.ac.jp

Affiliation Director General Office for Policy Planning and Evaluation, Ministry of Health, Labour and Welfare Japan, 1-2-2, Kasumigaseki, Chiyoda-ku, Tokyo 100-8916, Japan

Toshikazu Kuniya

Affiliation Graduate School of System Informatics, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan

Yoichi Enatsu

Affiliation Department of Mathematical Information Science, Tokyo University of Science 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: RO. Performed the experiments: RO. Analyzed the data: RO. Contributed reagents/materials/analysis tools: RO. Wrote the paper: RO. Mathematical analysis: RO TK YE.