What is a FoR assessment in terms of antimicrobial efficacy?

I will shortly learning about FoR assessments, however I cannot find any literature on it. I am unsure if I have been given the incorrect acronym or I’m just not searching correctly. I have tried “FoR” but everywhere I search seems to think I mean the word ‘for’. Tried all sorts of scholarly pages with no luck. Happy to be corrected/text replies or video replies. Any help is much appreciated.