With regards to deleting prior incidents or near misses which were recorded, you can utilize the mis-record functionality.
When entering a test or duplicate incident you can move it to the mis-record section and it will be as good as deleted.
In order to move an incident/near miss to the mis-record section, please follow these steps below.
Click on the Cases tab,
Select your particular case which you want to move by selecting the tick box on the left-hand side.
Click on the Mis-record button, this is the furthest right button and is located to the right of the "Tools" section.
4. Finally, you answer the question "Why is the incident being removed from reporting" and then click the green OK button.