In my experiences, we've not placed reports (or other 1-and-done types of documents) under change management as they typically don't have a lifecycle like QMS documents do... a report typically won't 'revise', and it is unlikely to become 'obsolete'.
I can see using a change management system to collect approvals, but then you are stuck with having to figure out the states and approvals for transitioning the record to a different life-cycle state. Typically a document control system also fixes the hierarchy of a document at the time of approval as well (*1)
The primary reason why I would argue against "reports" going into a PDM system is that typically the records belong to a different class of "file", such as a Design History File (DHF) or a Device History Record (DHR).
(*1) Mature organizations will specify a meaningful hierarchy for reports/records, but it is "easy" for something like a DHF to be (re)organized at the whims of the file owner. Even DHRs can be shuffled around (not lost!) according to all sorts of whims (preference of the filers to have Serial Numbers in order, dates of PO filled, whatever)... and such 'ad hoc reorganizing' is generally a no-no once a document is put into change control. DHF and DHR contents fall more into the "retrieve the record" category. There is an additional concern that having all sorts of documents unattached to structures (QMS structures, or DMR/recipes) can have the appearance of a change control system 'out of control'.
EDIT: Catching myself and my use of DHR, DHF and DMR