1) Medical Safety Section, Shiga University of Medical Science Hospital, Otsu, Japan
2) Department of Surgery, Shiga University of Medical Science Hospital, Otsu, Japan
3) Hiroshima University Hospital, Medical Safety Section, Hiroshima, Japan

Tomoharu Shimizu¹⁾, Toru Miyake²⁾, Sachiko Kaida²⁾, Hiroya Iida²⁾, Yuko Ogoshi¹⁾, Naoko Ibuki¹⁾, Ryoichi Mandai¹⁾, Yoshihiro Ikuno¹⁾, Takashi Murakami¹⁾, Hideki Ito³⁾, Jun Hanaoka²⁾, Masaji Tani²⁾