The Guidance on Ministerial Ordinance on Good Clinical Practices (PFSB/ELD Notification No. 1228-7 of the Evaluation and Licensing Division, Pharmaceutical and Food Safety Bureau, Ministry of Health, Labor and Welfare, dated December 28, 2012.Hereinafter referred to as the Guidance on GCP.) indicates that not all clinical trial data has to be verified against the source data for trial monitoring. Introduction of this kind of risk-based monitoring is expected to increase efficiency of trial operations as well as to ensure safety of the subjects and the integrity of clinical trials.