We positioned the access areas according to patients’ transit times from each hospital in order to create a
model of patients’ hospitalization. Patients’ accessibility to the hospitals is very important when we consider
their and their families’ burdens. In this model, we assumed that each hospital could admit patients only from
within its access areas. On the other hand, from the patients’ point of view, they were allowed to enter hospitals
when the meshes they were living in were within access areas. We used this model to simulate the
hospitalization of patients. We named our model the Patient Access Area Model. Fig. 1 shows an overview of
our Patient Access Area Model.
We classified all of the hospitals in Chiba Prefecture according to the number of beds. Hospitals with less
than 100 beds were classified as “small hospitals,” those with less than 400 beds yet greater than 100 beds were
classified as “medium hospitals,” and those with greater than 400 beds were classified as “big hospitals.” Next,
we set the transit time according to the classification of the hospitals. The transit time was set to 15, 30, and 60
minutes for big, medium, and small hospitals, respectively. An access area was assumed to be the accessible
field by car within the transit time from each of the hospitals. We investigated the access areas by using the
GIS and the “ACT Distance Calculation Service” provided by Advanced Core Technology Co. Ltd. [10].