SciPROOF will check the spelling of everything in your Word document including text that is within the field codes inserted by your bibliographic software.  Any corrections you make to the spelling in these fields will be lost once you format your bibliography again using "Cite While You Write" (CWYW).  You will need to either update the references in your database as you proceed or wait until you have finished your document and correct the spelling then.  Most publishers require that you remove field codes before submitting to a journal so a good time to do the final spell check is after you have unlinked the field codes.