confirmatory

adj

1. Serving to confirm something.

   “I replied, as I usually did whenever I had a chance, that nobody had ever loved anybody else as I loved Dora. Traddles came to my assistance with a confirmatory murmur.”

   “"Do you come to me, Master-at-arms, with so foggy a tale? As to Budd, cite me an act or spoken word of his confirmatory of what you in general charge against him. […]"”

   “1986, Mark S. Gold and A.L.C. Pottash, Diagnostic and Laboratory Testing in Psychiatry, New York and London: Plenum Medical Book Company, Chapter 3, p. 43, https://books.google.ca/books?id=KGSxQ_-94J8C&printsec=frontcover#v=onepage&q&f=false The main indication for performing the DST is for the confirmation of suspected major depression. A positive test is excellent confirmatory evidence of the diagnosis.”