Assigning a checklist
You can assign a checklist to a particular user, which means that only this user can sign off a particular checklist (and the checks within it).
All users must sign off all checks for the % completion to hit 100%.
1) Open the checklist
2) Just hit 'assign user' and a list of users will appear
Changing who signs off a checklist
1) If you need to change this at any time, you can select the cross by that person's name, and simply add someone new!
(Note, if you delete a person, any audit trail that they have signed any checks off will also be deleted.)