Hi Colm,
According to the FDA data standard catalog, “Date Requirement Begins” for GENC terminlogy is 12/17/2020.
If the study began after 12/17/2020, GENC is applicable for FDA submission. And, GENC uses ISO 3166 names and code elements wherever possible, with modifications only where necessary to comply with US law and US Government recognition policy. I have yet to see a case where the GENC 3 Letter Code (FDA standard) and ISO 3166 are different.
If the data should be prepared for FDA submission, I think it’s worth double-checking country code against the GENC code.
And it has more to do with CDISC than Pinnacle21. Please refer to the LinkedIn “SDTM experts” forum (LinkedIn Login, Sign in | LinkedIn) or the LinkedIn Define-xml forum (LinkedIn Login, Sign in | LinkedIn) to hear more opinions.