Medical Profession - Requirement for Patient’s Valid Consent
From the book "Law for the Medical Profession in Australia Second Edition by Andrew Dix BA LLB (Syd), Michael Errington BA LLB (Syd) LLM (Lond), Kevin Nicholson BA LLB (Syd) LLM (Camb) Rod Powe LLB (Hons)Tasmania at  B.
THE REQUIREMENTS FOR VALID CONSENT
[505'Generally. Merely because a patient has agreed to a proposed course of action does not, of itself, mean that the patient has validly consented. An abstract consent is not sufficient.
To be effective, the consent of the patient must:
(1) be freely and voluntarily given  - ;
(2) cover the procedure to be performed -;
(3) cover the person who is to perform the procedure ; (b) be given by a patient who is competent (capable) of consenting [511-; and
(5) be informed to some degree .."
and at  Trespass..
'Trespass', with a central reference on direct, unauthorised interference, is a generic term for several causes of action, the most relevant in the present context being 'assault' and 'battery'.".
and at " A duty to disclose? …would have to show that inherent in the duty of care was an obligation on the practitioner to provide certain information and, further, that if that information had been given to the patient, on the balance of probabilities, the patient would not have consented to the procedure being carried out ", " Disclosure of inherent risks and complications…"