<unk>  is a legal condition whereby a person can be said to have given<unk>  based upon an appreciation and understanding of the facts and implications of an action.  The individual needs to be in possession of relevant facts and also of his reasoning faculties, such as not being mentally retarded or mentally ill and without an impairment of judgment at the time of<unk> ing.  Such impairments might include illness, intoxication, insufficient sleep, and other health problems. Some acts cannot legally take place because of a lack of<unk> .  In cases where an individual is considered unable to give<unk> , another person is generally authorized to give<unk>  on their behalf. Examples of this include the parents or legal guardians of a child and caregivers for the mentally ill. In cases where an individual is provided limited facts, serious ethical issues may arise.  Examples of this in a clinical trial in medical research are anticipated and prevented by an ethics committee or Institutional Review Board.
Informed consent
Withdrawal of consent
Scientific consensus
Chain of survival
Shared decision making
Research ethics
Evidence based practice
Incident report