To enable an operator to easily detect a proper diagnosis by displaying an effective applied diagnosis at a relevant medical department preferentially in accordance with the medical department where a relevant patient is consulted when a reference diagnosis that can be the applied diagnosis of the prescribed medicines.

An applied diagnosis which is effective in a relevant medical department is displayed preferentially in accordance with the medical department where a relevant patient is consulted when a reference diagnosis that can be the applied disease name of the prescribed medicines. In this method, a department code showing the consulted medical department is read out of a medical data file 20 of the patient to refer to a section table 15 (R33). Thus, a medical section corresponding to the department code is obtained (R34). A diagnosis check part 13 reads a master code having the said medical section out of the storage contents of a memory 14 (R35) and outputs a relevant diagnosis. The master codes having the relevant medical sections are successively extracted in the order of upper positions and outputted to a monitor screen or a printer.