This incidence rate evaluation device is characterized in being provided with: a storage unit for storing diagnostic information, which stores regions of the body associated with differences between two images taken of the region at different times and with a disease name； and a control unit for receiving input of an image feature value category and the region to be diagnosed from a user, calculating the difference in the received category between the two images of the region that is being diagnosed in the patient and have been taken at different times, searching the diagnostic information using the region being diagnosed and the calculated difference as search keys, acquiring disease names of relevant records, calculating incidence rates on the basis of the percentages of the relevant records in the total number of records for the region, and displaying the calculated incidence rates for each acquired disease name.本發明之罹患率評估裝置之特徵為：具備有：記憶部、及控制部，該記憶部係儲存與身體的部位產生關連地被記憶對部位進行攝像的攝像時點不同的2個畫像的差分、及疾病名的診斷資訊，該控制部係接受使用者輸入畫像的特徵量的類別、及成為診斷對象的部位；針對所接受的類別，算出對診斷對象者之成為診斷對象的部位進行攝像的攝像時點不同的2個畫像的差分，將成為診斷對象的部位、及所算出的差分作為檢索鍵，檢索診斷資訊，取得相符記錄的疾病名，根據相符記錄的數量相對於具有部位的記錄的數量所佔比率來算出罹患率，按每個所取得的疾病名，顯示所算出的罹患率。
