Except for faculty/real world job positions- where the interview is THE way you get the job– I think the interview does not meaningfully distinguish candidates, except to weed them out. I think it’s incredibly hard to positively distinguish yourself in the short time vet school, internship, and residency interviews give you (i.e. less than a couple of days). It is exceptionally difficult to be a +1 in a short interview. You are FAR more likely to fall flat on your face and provide the impression of being a -1. How do you avoid having your application cut due to the interview?
Aim for Zero – This HAS to be step one because I cannot possibly emphasize this enough. The interview is unlikely to help you stand out and is much more likely to sink your application, so you just need to NOT SUCK. Don’t try to impress them. Don’t be flashy and memorable. You got the interview. They basically WANT you. So just aim for zero.
Watch Your Words – Be an RFHB. Be respectful when talking about other people, particularly past mentors. Don’t bad mouth anyone. Remember, at this point they are looking for reasons NOT to accept you. Don’t give them any reason because of a bad attitude.
Be Interested – Although I think it does help to smile and be positive, you at least need to be not disinterested. It’s always demoralizing when I have an interview with someone who just doesn’t seem to want to be there. You at least need to project the impression that you will show up and be engaged. If you aren’t interested, why are you even applying? Convey that interest during the interview.
Be Humble – Don’t brag or boast. Don’t talk constantly. Don’t dominate the conversation or the interview. I HATE it when someone interrupts me, and from an interviewee (over whom, presumably, I have some measure of power) it shocks me into immediately marking them down. If you think you’re the best thing since sliced bread, that comes across and is an immediate “no” for me and many others. Unfortunately, if this is part of your personality, it will probably take years of therapy to remedy. But if you do have control over it, be mindful to be humble throughout.
Just Be Cool – Be genuine. Try to be the best version of yourself while still aiming for zero. Try to relax. The interviewees who impress me the most are quietly competent. Do your best and focus on answering the question as asked, project who you are, and be professional.
In my opinion, the interview rarely distinguishes the top applicants from the middle applicants. Although there are certainly rare gems (I would say 1-2 applicants/cycle) who impress me in a positive way, the vast majority of notes I make are about the applicants who impress me in a negative way. Avoid getting yourself cut during the interview. Aim for zero, be an RFHB, be humble, and you will do just fine.