Thanks for reading and thanks for your question estherglass. First congratulations on getting into medical school. I wish you the best on this new journey. It will be both exciting and hard and worth every minute of it. :)
From my talks with some upper years, competitive residencies get ultra competitive. They usually take very few students and you are competing nationwide so it does get tough once you put in your choices. When residency reviews come along they see the H, P or F. If you made it that far you have gotten Ps or Hs. I am not sure if they see the grades or not. What I have been told is more important are the reference letters. Getting a great recommendation from a doctor in that field that you did a rotation with can make a huge difference. These are typically more crucial than EC and research.
Having said that, I have heard conflicting information on research. Some say it’s important; others say it’s not that important. While it is nice to have done research and it does kind of impact your standing in CaRMS, it will most definitely benefit those who have done a lot of research. When you think of comparing a PhD/MD with multiple publications to a student MD who has his name onto a two-month project, those two are not equal. Given that though, I think if you can do research it is always nice. It is a different experience to being a physician. If you are thinking to incorporate some clinical research into your practice in the future, this can be your first look at whether that is right for you.
Hope that answered your questions. If not, feel free to message me again. Cheers! :)