On the configuration page you have the option to filter comments before they are used to calculate and generate the custom fields.
You have the following options:
All comments – uses all comments available (default)
Public comments only – only use the comments marked as public in Service Management
Exclude public comments – exclude the comments marked as public in Service Management
JSM specific fields
The app has two JSM specific fields to differentiate between internal and public comments:
internal comment count
public comment count
These fields are helpful in case you want to measure internal or public comments in some way.