These examinations require volunteer patients with clear physical signs (e.g. a heart murmur) that can be found by a skilled doctor when they examine a patient, or symptoms (e.g. breathlessness). The use of "real" patients in clinical examinations allows the candidate to discover abnormalities on examination in a way that actors and manikins cannot, and gives the students an opportunity to demonstrate their knowledge, attitudes, behaviours and skills in a much more reliable way.