How to get your partner into a true roleplay

Does anybody have any suggestions to - how I can persuade my wife to do a play exam? Nothing much - just a rectal temperature and some light examination of penis/vagina and anal inspection. How and where do you start? She is shy, and don't know what to say - she feels out of place so to speak. So - do you have any advice or should I just leave it be?

Do it in writing. Give her a suggested play scenario and tell her you want her to edit it and add her likes. You can go back and forth several times then do it.