I guess that the text before the colon is just that, background text. If that's the case you can use the following:
msgbox " Statement ID: " & me![IDControlName] & vbcr & _
" Parent: " & me![ParentControlName] & vbcr & _
" Statement Amount: " & me![AmountControlName]
However you will have to edit the number of spaces a few times until the display is the way you want it because message boxes don't quite handle spaces the way you expect.
As an alternative try using a form with the pop-up property set to "yes" to display the values, the layout of them is much more flexible and easier to control. If you have problems passing the information from the main form to the pop-up form define global variables in a module, update them from the event procedure that opens the pop-up form (where you'd put the msgbox call) before you open the pop-up and update the variables in the pop-up from the global variables in the onCurrent or onOpen proceure of the pop-up.
Hope this helps