Find patients that have cancelled for a certain reason

With a contact list query you can list patients who match the condition Cancelled appointment with reason:

Select Administration > Contact Lists, then “Create List” in the bottom right
In the Create Contact List window click the Select a Query Template (or CTRL-L).
In the View Query Templates window click +1.
In the Add Query Template window, click the Insert button (or CTRL-I).
In the Select Condition window scroll to and select the condition Cancelled Appointment then select the date range that the cancelled appointments fall into
Click the Insert button (or CTRL-I) again and then select Cancelled Appointment with Reason then Click OK.
Select the Cancellation Reason then Click OK. Specify any other parameters if necessary.
Click OK to return to the Add Query Template window, with your condition/s selected.
Type a Description (if you didn't earlier), add any further patient selections and arrange them with AND / OR logic
Click OK to return to the View Query templates window, where you will see the new template highlighted:
Click OK to return to the Create Contact Lists screen., and OK again.
You will see feedback on how many patients meet the conditions of the query and click “Yes” to create/save the list. To create an updated version of the list, re-run the search query you’ve just created, changing date ranges first, if required.

When creating Contact List you will then be able to select this from the View Query Templates window::