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This is a sample for a symptom checker customised for checking the symptoms of COVID-19. The model takes the symptoms and certain other details of a patient and as the output, it provides recommendations to show what to do next.
How to Run
1. Open the file DRD.xml in FlexRule Designer.

2. Click on Logic Run Template.

3. Select a template from the list

3. Click on Debug.

4. Click on the Next Step to see the steps until the project executes successfully. Here you will see how the project runs step by step.

5. After the execution is finished successfully, the recommendation can be seen under the Parameters window.

Project Description
Decision model
The decision graph automatically resolves the dependencies between logic implementations. That means this Decision Requirement Diagram knows that to provide the recommendation, it requires both patient details, and the decision was taken from COVID-19 Symptoms and goes through each node accordingly.

This is the process:
- Input patient details
- Check whether the patient has symptoms/ extreme symptoms
- Provide a recommendation as to the output
Patient details concept
Patient details are modeled as a fact concept. It also defines the symptoms and the extreme symptoms.

Business glossary
Define the business terms in a business glossary. This will make it easier to understand the concept as here we map our fact concept in a human-readable manner.

Check for symptoms
A decision table is used to check for the symptoms. As the action, it assigns an action code for each patient.

Provide recommendation
Another decision table is used to determine the detailed recommendation according to the action code received from the symptom checker decision table.

Video Description
Project Steps
- Create a Fact Concept to define the patient details (Concept.xml).
- Create a Business Glossary to define business terms (BusinessGlossary.xml) connecting the created fact concept.
- Create a Decision Table to check for the symptoms (Covid19 Symptoms.xml) and determine the action code.
- Create another decision table to provide the recommendation according to the action codes (Action Codes.xml).
- Finally, create the Decision Requirement Diagram (DRD) to map the decisions (DRD.xml).
Download the project
Use the attachment at the end of the page to download the sample project.