Effects of preventive home visits on health care costs for ambulatory frail elders: a randomized controlled trial.

"Conflict of interest The authors have no conflicts of interest related to the present article."

"The authors would like to thank the Japanese elders and their family members for their participation in this study. We express our gratitude to the staff of the Long-term Care Insurance Sections of the Izumiotsu, Misaki, and Sennan government offices and their Community-based Comprehensive Care Centers. This work was supported by grants from the Japan Society for the Promotion of Science (Kiban-B Grant No. 18390603; PI: Ayumi Kono)."

"The purpose of the study and the process of analyzing the health care cost data from local government documents were explained to the study participants. The present study protocol was approved by the Nursing Research Ethical Committee of Osaka City University (No. 19-3-3, October 01, 2007) and was registered at the UMIN clinical trials registry approved by ICMJE (No. UMIN000001113, April 07, 2008)."