You are overthinking this.
Most doctors are dressed like shlubs.... and I'm certain most of the interview committee will be doctors.
You will probably see an array of square toe shoes, loud ties and questionable fitting sport coats/blazers from the interviewers.
The tie will be fine. The fact you are wearing a suit is enough unless you are so marginal a candidate that you need to pull off a real good first impression.
That being said, I would also go...