Information Technology Reference
In-Depth Information
For the system we have chosen the
maximum
and the
minimum
as t-conorm and t-
norm because of their simplicity, and therefore, efficient and fast calculation as well
as they are quite extended.
Hence, we include in the system three degrees of pertinence defined by doctors or
medical criteria: one associated to the regulations (
P
Dc
∈
[
0
,
1
]
), another one related
to the personal opinion of the doctor (
P
Dc
∈
[
0
,
1
]
) and the other one associated to
the specific patient (
P
Dc
∈
[
0
,
1
]
).
23.4.3
Contextualized Access System
With all the elements to implement the contextualized access to the EHR, we show
next how we propose to provide this access by presenting the use of the proposed
method, as well as the update process that allows the system to automatically adapt
to new needs.
Access to the System
An scheme of the access process in shown in Figure 23.7.
•
The doctor starts the process by logging in the system.
•
Using the information about the terminal and the schedule of the doctor, the
system gets the
context
for this access using the simple rule system.
•
The doctor identifies the patient in the system to access his/her EHR.
•
The system gets the EHR and queries the static and dynamic pertinences for
all the data groups that appear in his/her EHR. The result of aggregating these
pertinences and the time pertinence as shown in equation 23.5 is used to order
the data.
•
Finally, the system selects the first data groups and returns them to the doctor
ordered y priority, as well as a way to access the other data groups if the doctor
needs them.
Update Process
The system is updated on each access so the pertinences are adapted continually to
reflect doctors' needs. In this process no manual intervention is needed and a few
records are changed so it needs a short time to be executed. The update process is
as follow:
•
When the doctor logs in the system, the context of the access is calculated as
mentioned above.
•
The doctor asks for a data group of a specific patient.
•
The system then gets the required data and returns them to the doctor. At the
same time the system logs the access in the RADB table and updates the fre-
quency table used to obtain the
retrospective pertinence
with this new access.
Only two records are changed: the accesses to the data group in this particular
context (
tf
ij
) and the total number of accesses to the context (
tf
j
).
