Medical doctors (physicians) study, diagnose, treat and prevent illness, disease, injury and other physical and mental impairments in humans through the application of the principles and procedures of modern medicine. They plan, supervise and evaluate the implementation of care and treatment plans by other health care providers, and conduct medical education and research activities.

Tasks performed usually include: conducting physical examinations of patients and interviewing them and their families to determine their health status; ordering diagnostic tests and analysing findings; prescribing and administering curative treatments and preventive measures; performing surgery and other clinical procedures; monitoring  patients’  progress and response to treatment; advising on health, nutrition and lifestyle behaviours which aid prevention or treatment of disease and disorders; identifying and managing complications before, during and after childbirth; planning, managing and implementing referral plans for patients in need of specialized, long-term or other types of health care services; exchanging medical information with other health professionals to ensure continuing and comprehensive care; reporting births, deaths and notifiable diseases to government authorities; conducting research into human disorders and illnesses and preventive or curative methods.