Of course, this made my head swim with its implications. Suppose your appointment is at 1:30, and the nurse says to arrive fifteen minutes early--that's 1:15, right? You still following this? So, instead, I suggest that they say your appointment is at 1:15, but please arrive fifteen minutes late. Anyone can be late...so, I'm sure that's the answer to help doctors and nurses increase efficiency.
Also, don't you just enjoy playing fun mind games with your doctors' staff? I know I do. If they call your name forty-five minutes late, you hand them a bill for your time. Be sure to point out, though, that you gave them the first fifteen minutes free. They really seem to enjoy this.