Is there a best practice? What are the advantages of a CDR vs. PAR (and vice-versa)? Can both be used? When should one be used rather than the other?
This is a GREAT question. First, we applaud you for taking the time and effort to revamp your QASP Template! Second, we applaud you even more for the research you have already undertaken.
BLUF: the CDR is used to document a specific deficiency or problem whereas the PAR is used to document ALL of the contractor’s performance of a period of time.
Both can be used and often are. But they mean different things. A Contract Deficiency Report (CDR) is a written process to document in writing and resolve identified contract deficiencies to prevent delays, inaccurate payments, and other potential negative consequences of those deficiencies.
The CDR is very similar (almost identical purpose) to the “Corrective Action Request” (CAR) that DCMA utilizes, and is also referenced at AFFARS (Air Force) PGI 5346.401 you included. In certain instances, CDRs can help collect the proper data so DCMA can identify the drivers of deficiencies and prevent or reduce future contract submission errors through their CAR process. That is unlikely in your instance because your Buildings and Grounds Maintenance Services requirements are most likely NOT delegated to DCMA for quality assurance oversight.
The Services Acquisition Mall (SAM) Performance Assessment Report (PAR) was designed to capture and document all of the contractor’s performance of a period of time. How all of it matches the performance standards and delivery requirements, not just deficiencies or problems. The PAR format was designed to coincide with the Contractor Performance Assessment Report (if you have heard of CPARS) identified and required by FAR subpart 42.15 to capture and document contractor past performance. You can see what the Army requires at AFARS subpart 5142.15 (it does reference a few Army Regulations).
Note: the PIEE - COR Surveillance and Performance Monitoring (SPM) module was designed and utilizes most of the formatting and principles that the SAM PAR (which predated PIEE and the CORT) was designed with.