The MD/PhD program in medicine is intended for students who are planning careers in academic medicine or biomedical research, or who desire formal research training to enhance their clinical skills. Typically, 6 - 7 seven years are required for completion of the MD and PhD degrees. Most students begin their studies with the first two years of medical school, followed by completion of graduate course work and dissertation research, and then by completion of the medical school curriculum.
Selected majors/areas of research for a combined MD/ PhD in Medicine include

Biochemistry and Molecular and Cellular Biology

Biomedical Engineering

Cancer Biology

Cell Biology and Anatomy

Epidemiology

Genetics

Immunobiology

Neuroscience

Nutritional Sciences

Medical Pharmacology

Physiological Sciences
Students in a medicine doctoral program must pass a written and oral qualifying exam and then complete and formally defend a doctoral dissertation based on original research. In general, all medicine PhD programs require that successful candidates for the degree demonstrate:

The ability to conduct independent research at a high level, leading to completion of a dissertation which is defended before a committee of scholars. Because examinations given as part of a PhD curriculum assess expert knowledge, they are created and evaluated by a committee of experts, each of whom holds a PhD degree

Proficiency in the tools necessary to carry out this research, including but not limited to computer skills, bibliographic competence, and reading of one or more foreign languages

Mastery of general and specific subject matter in the field of study before a committee of scholars
Part- and full-time study options, along with various delivery modes - residential programs, distance education programs and online programs - are also available. North American PhD programs in medicine welcome foreign students. However, fluency in spoken and written English is critically important.