 Typically, in order to be deemed legally and ethically valid an individual’s consent must be properly informed and free of external coercion (Faden &amp; Beauchamp 1986). Given that in most medical contexts there is a huge asymmetry in possession of knowledge, disclosure is usually required to ensure that the subject is informed, and is often listed as a requirement. Against this backdrop decisional capacity is often thought of as a fourth requirement of validity. Thus many health care professionals think of informed consent in terms of a four-part checklist: