Explaining Medical Model Exceptions - Computational Intelligence in Healthcare: Advanced Methodologies - page 265

Fig. 3. ISOR's main dialogue menu
The next step means creating an explanation for the selected patient “D5”. From
the case base ISOR retrieves general solutions. The first retrieved solution in this ex-
ample, the PTH factor, denotes that the increased parathyroid hormone blood level
may explain the failure. Further theoretical information (e.g. normal values) about a
selected item can be received by pressing the button “show comments”. The PTH
value of patient “D5” is missing (-9999). In step 10 the expert user can select further
probable solutions. In the example, an increased phosphorus level (P) is suggested.
Unfortunately, phosphorus data are missing too. However, the idea of an increased
phosphorus level as a possible solution should not be lost. So, an artificial case should
be generated.
The final step means inserting new cases into the case base. There are two sorts of
cases, query cases and artificial cases. Query cases are stored records of real patients
from the observed database. Artificial cases inherit the key attributes from the query
cases (step 7 in the menu). Other data may be declared as missing. By the update
function the missing data can be inserted later on. In the example of figure 3, the gen-
eralised solution “High P” is inherited; it may be retrieved as a possible solution (step
9 of the menu) for future cases.