There are three options for the access restriction: Restricted access, Restricted Filter and Restricted Target Audience.

Restricted access: Users have no access to feedback from questionnaires (and questionnaires themselves) unless they have been explicitly authorised to the questionnaire.

When a user enters the improvement ideas from the menu he cannot access all ideas. However, if you are using the restricted access, all users (Expert, Admin and Improver - Dashboard viewer) can change/clear their filters in order to have a view of all improvement ideas.

Restricted filter: This setting restricts all users from changing their filter (location, department, team and tags). Only a user with 'administrator' rights can change his own and the filter for other users.

Users (Expert and Improver - Dashboard viewer) no longer have the ability to change their filters (location, department etc) so they only see the improvement ideas with the matching filters.

But they still have the option to “Show items that apply to the entire organisation” and then they can access more improvement ideas (the ones that are not matched with any filters).

Admins can still change their filters and access all improvement ideas.

Restricted target audience: This setting restricts all users from changing their target audience. Only a user with 'administrator' rights can change his own and the target audience for other users.

Admins can still change their filters and change all improvement ideas.

Other users (Expert and Improver - Dashboard viewer) have the ability to change their filters (location, department etc) but not the target audience so in our case they can still see all the improvement ideas.

Here is a matrix to help you better understand the differences of the three options for the restriction access:

TitleRestricted filterRestricted target audienceRestrict access
DescriptionThis setting restricts all users from changing their filter (location, department, team and tags). Only a user with 'administrator' rights can change his own and the filter for other users.This setting restricts all users from changing their target audience. Only a user with 'administrator' rights can change his own and the target audience for other users.Users have no access to feedback from questionnaires (and questionnaires themselves) unless they have been explicitly authorised to the questionnaire.
AccessUsers only have access to questionnaires and feedback that match their filters (admins can see all)Users have access to all questionnaires and feedback that match their target audience (admins can see all)Users have access only to questionnaires and feedback they have been explicitly authorised to (admins can see all)
MaintenanceRather time consuming: each user needs to be matched with the correct filtersQuickest: users only need to match with a target audienceMost time consuming: each users needs to be added to every single questionnaire they want to view
SecurityVery secure if filters are set correctly: users only view the questionnaires and feedback that match their filters. Keep in mind that it is possible to make mistakes while matching the filters and this can result in accessing wrong data or not having access to dataNot very delicate: users see all questionnaires that have to do with their target audienceMost secure: users only view questionnaires and feedback they have been explicitly authorised to
Can users change their filters?Only adminsYesYes
Can users change their target audience?YesOnly adminsYes
Can a user be constrained from seeing a questionnaire?No, they can see all questionnaires matching their filtersNo, they can see all questionnaires matching their target audienceYes, a user is constrained from seeing every questionnaire in which his/her name has not been added.
Consequences on the improvement boardUsers only have access to improvement ideas that match their filters (admins can see all). plus items that are not matched with any filters if they choose to “Show items that apply to the entire organisation”Users have access to improvement ideas that match their target audience (admins can see all)Users have access to all improvement ideas if they clear their filters

Conclusion

You can update your access restriction based on which users you want to be able to access improvement ideas.

If you want to restrict users from viewing all ideas then what you need to do is to change to “Restricted filter” and match all ideas with filters. That way, only the relevant users can view the improvement ideas. Even if a user turns on the option to “Show items that apply to the entire organisation” they won’t view any extra ideas since all of them will be matched with the relevant filters.

Please keep in mind that changing the access restriction on your account does not only affect the improvement ideas but also the access to questionnaires and their feedback.

Diagrams
If you are still not sure of what choice to make, the following diagrams might help you out.

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