After changing the checkbox, you can double click on the queryname in the navigation pane to see what it pulls. That will give you an idea of how it can be used for all the comboboxes and forms that need to see either active or inactive members.
Or you can simply watch the number of records at the bottom of the form's Navigation Buttons change as you click the checkbox to see how it works. It's all about how qry_MembersSelected is modified by the checkbox.