What welding standard or code are you working to?
NAVSEA TP278 requires the manufacture/fabricator to establish a system to independently verify the test reports and materials supplied by vendors are accurate (paraphrasing the requirements). Many of my clients will send a representative sample of filler metal to a lab to have the chemistry of the "wire" determined and compared to the chemistry listed on the material test report. Likewise, a chemistry of the weld deposit of the PQR can be compared to what is reported on the supplier provided test report when SMAW electrodes are used.
AWS D1.1 does not require independent verification of the weld chemistry or of the filler metal chemistry.
Each code or standard has different requirements. What does your welding standard or code require?
Best regards - Al