Originally Posted by cardiomd

Way back in residency, I used to use a backpack for all my stuff coming to and from the hospital. One day one of the older docs scolded me and said I shouldn't use a backpack. I was like "why??" and the next day I looked around -- I realized I was the only person who was still using a backpack. I haven't used one since.

Backpacks are comfy (and probably better for your back than side cases) but as LNL said they are viewed as unprofessional by many.