From my experience, I felt that the phone interview was more serious/standardized as compared to the virtual interview. The phone interview really focused on the questions asked whereas the virtual interview felt very conversational and more of a "vibe check" rather than an actual interview. My guess is that they use the phone interview mainly to evaluate competencies (communication, service orientation, resilience, etc).
With that being said, for the phone interview, I would prepare by having some solid answers to typical job interview questions like "what is your greatest strength/weakness" or "tell me about a time you failed." I would also be prepared to share your thoughts on the medical field. And as others have mentioned both here and on Reddit, there are some questions that are more "unique" and require you to think on your feet. You can't really prepare for them but I personally found those questions fun to answer and I think they just want to see your thought process.
Another thing that I found helpful was to speak in an excited tone and smile throughout the interview (even though they can't see you). I think this helped with transmitting a positive energy through the phone and I think it got my interviewer to loosen up a little bit. During my prep, I read online from previous years that the phone interview was kind of awkward because the interviewers are supposed to be stoic and give you any indication as to how they viewed your response. But for my phone interview, my interviewer conversed with me and even joked around a few times, which I wasn't expecting but I think was due to how I spoke from the moment I answered the call.
Finally, I highly recommend remembering/writing down your interviewer's name in the beginning and using their name in your responses as it makes the interview feel more personal and memorable. And definitely thank your interviewer for their time before ending the call.
Good luck and let me know if you have any other questions! More than happy to help!
