What is the test for battery in medical malpractice cases?

The test adopted by Lamer C.J.C. in Reibl v. Hughes clearly distinguishes between the case where the failure to disclose relates to the nature of the procedure or treatment and the case where a failure to disclose is not so basic as to vitiate consent but rather is to be addressed in negligence. He states at p. 890-892: In my opinion, actions of battery in respect of surgical or other medical treatment should be confined to cases where surgery or treatment has been performed or given to which there has been no consent at all or where, emergency situations aside, surgery or treatment has been performed or given beyond that to which there was consent. [...] I can appreciate the temptation to say that the genuineness of consent to medical treatment depends on proper disclosure of the risks which it entails, but in my view, unless there has been misrepresentation or fraud to secure consent to the treatment, a failure to disclose the attendant risks, however serious, should go to negligence rather than battery. Although such a failure relates to an informed choice of submitting to or refusing recommended and appropriate treatment, it arises as the breach of an anterior duty of due care [...] It is not a test of the validity of the consent.