We analyzed 197 fall incidents in the questionnaire survey about the incident that occurred in Department of Radiology. In the past paper about the patient safety, there is no report that evaluated incident data directly. The purpose of this paper is to analyze the factor of the medical incidents using statistical technique scientifically. In this paper, we do not suggest concrete precaution. At first, we found the number of patients (each gender, modality, generation) in the five facilities of the coworker of one week. We found an incident rate from this patient total number, and we normalized data. As a result, we were able to do each risk evaluation because a risk ratio and relative risk degree was found. And, we were able to identify modality and the generation with the significant difference using the testing for differences in population rate. By our analyses, we revealed the chapter which must strengthen safety management.
Keywords: environmental factor; evaluation; fall; patient safety.