All postings to a moderated list must be reviewed and approved before they are distributed to all subscribers to the list.
Reviewers can be all owners to the list or specified owners.
It is a judgement call as to whether or not you set your listproc list up as moderated or not. You might want to see how postings are handled by subscribers before restricting the postings. A listproc list can be re-configured to a moderated list after it is set up.