To enable a reference medical worker to surely make a call to a medical worker in charge without directly inputting a terminal number when the reference medical worker refers to the medical worker in charge of a patient.

When the patient for inquiry is selected, terminal identification information on a portable communication terminal 20 carried by the medical worker in charge is obtained and transmitted to a portable communication terminal 20 carried by the reference medical worker performing authentication. The portable communication terminal 20 which receives the terminal identification information transmits a call signal to the portable communication terminal 20 to be identified by the terminal identification information. Consequently, the terminal identification information on the portable communication terminal 20 carried by the medical worker in charge of the patient is transmitted to the portable communication terminal 20 carried by the reference medical worker only by selecting the patient. Then, calling is performed from the portable communication terminal 20 carried by the reference medical worker to the portable communication terminal 20 carried by the medical worker in charge.