Types of consent required for health care
In Australia, it is always presumed that a person has capacity to make decisions, including consent for treatment, unless their capacity to make the decision can be formally shown to be otherwise; see Assessing capacity of a person with developmental disability to make decisions. Supporting medical evidence from a general practitioner or other health professional(s) (eg psychologist) is required.
Even if a doctor considers that a person does not have decision-making capacity, or the person has a guardian appointed, consent is not required when health care is minor and uncontroversial (eg physical examination, blood tests, noninvasive investigations such as X-rays and ultrasound), and the person is not objecting to the treatment by word or deed. Any such procedure and implied consent should be clearly documented in the person’s medical record.
Informed consent is needed for most procedures, particularly more invasive examinations (eg vaginal or rectal examinations) and invasive investigations. This should come from (in order of preference) the:
- person (if they have capacity or can be supported to make an informed decision)
- substitute decision maker (if the person lacks capacity)
- appointed guardian.
Advice should be sought from the relevant guardianship authority for forensic examinations, which should be performed by a clinician with appropriate expertise.
Certain highly invasive or irreversible procedures require special authorisation from an external body (eg guardianship tribunal). These include termination of pregnancy, sterilisation, and removal of nonregenerative tissue for transplantation.
Consent is needed for participation in an approved clinical trial. In most states, consent can be given by a substitute decision maker if one has been appointed (see Substitute decision making).
If a person has a guardian appointed, or their decision making rests with an informal carer, the nature of consent for health care differs slightly in each state and territory. A webpage produced by Queensland University of Technology includes links to laws in each state and territory on decision-making requirements for treatment (including consent for emergency medical treatment) for adults and children.
Procedures for obtaining consent may vary in different states and territories. If in doubt, contact the local guardianship authority.
All states have legal provisions that protect a medical practitioner who gives medical treatment to an adult when relying on the purported authority of a person to give substituted consent. This protection applies if the medical practitioner did not know, or could not reasonably be expected to have known, that the person did not in fact have that authority.