As far as i know , The uai is JUST a cutt off , once you get past that , getting into med is totally based on how you go in your umat and interview , but thats is in theory . What happens is that they end up with soo much people with the same marks in the intervview/umat and end up using the uai's as well to determine wether u get in . So basically if 200 people applied and all of them got the same cumulative uai/umat mark then according to how high thwir uai's are they will get in , and only the highest 100 people will be abllowed entry .
If at this stage there are people with the same uai , umat and interview marks( WHICH IS EXTREMELY UNLIKELY BUT STILL POSSIBLE ) then thats where they refer to your application form where you were asked a series of questions about yourself . And depending on their judgement of that they will chose who goes in .