The interview day goes from around 10am to 2pm or so (depending on what order you are interviewed). You will be with about 4 other OD hopefuls. Pepare for your interview as you would a job interview. They will ask you the obvious:
Why optomtery?
What is an optometrist?
How has optometry developed over the last 20 years?
What are the duties of an optometrist?
What aspects of optomtery are you interested in?
etc.
Make sure you pay attention to Dr. Brown's presentation in the begining. If you are nervous, remember, she GIVES YOU almost all of these obvious answers (except for subjective/personal ones). Do not be nervous. I have interveiwed at a few places and this was the most laid back. I truely belive if you are sitting in the chair at UMSL you are basically in as long as you don't freak out/clam up/act stupid during the interview. Compared to other schools this was a breeze.