Oh, I see what you mean now. A common problem! To be honest, if the First Name, Surname, DoB and Post Code are the same then that's pretty likely to be a match. What I tend to do is add the address details in – but only if the postcode we have is different to that one in the likely match.
It is actually very unlikely that the address details will be there already. The schools/colleges in our area don't seem to send much info – we only send the bare essentials to MIAP ourselves.
Don't forget that they come up as possible matches because of dodgy spellings in their names, the date of birth has been transposed or there is a slight of hand with the postcode – sometimes it's easy to spot, other times you can be staring at the screen for what feels like hours trying to figure it out.
I've even reported to MIAP myself that it has sometimes come up with a possible match because the ID type we'd got on our system was different to the one on MIAP!
Cheers
James