*At least one letter from a PhD level faculty member who has taught you in a natural science course. Many schools will ask for two of these letters so we would strongly recommend requesting two.
*At least one letter from a clinically based experience in the profession you are applying for.
*For anyone applying to a combined PhD program, a research letter is required. A research letter is recommended for other applicants who participated in research.
*Some DO medical schools may recommend a letter from a DO physician, but it is not often required.
*Some schools may recommend a faculty letter from a non-science course (humanities and/or social sciences). Please note the non-science letter does not need to be from a PhD level instructor.
*Other letters would depend on what other activities you participate in and could include areas like community service, athletics, leadership positions, and other professional positions. Consider who knows you best in an academic or professional capacity.
*Letters from family or close friends are strongly advised against.