Managing Cohorts
While the term "role" defines the security permissions a user has (e.g. what a user can do), the term "cohort" defines the security group for a user (e.g. who a user can do it to). In other words, the role of "Supervisor" allows a user to view the compliance report. The cohort the Supervisor is in charge of determines who they can see in the compliance report.
To a large extent, cohorts are created automatically by the learning environment if it's integrated to your OSS/BSS systems, such as an HRIS or Active Directory server. That being said, you can manually create cohorts to represent a group by role, function or department, and then allow an administrator of that cohort to view its members in reports. For example, if you'd like the Volunteer Administrator to be able to run the compliance report but only for volunteers, you could create a "volunteer cohort", set the Volunteer Administrator as the administrator of that cohort, and set volunteers as members of that cohort.