If a doctor failed to get the patient's consent to treatment, the treatment was regarded as a battery. This view of malpractice evolved into the theory of informed consent. Under the concept of informed consent, the doctor must not only get the patient' s consent to treatment, but the treatment must be obtained from a fully informed patient. Because the medical liability theory involves the concept of a lack of consent to a procedure, a patient may be able to recover damages even if the medical procedure was successful. In a lawsuit for negligence, the patient must be able to show that the treatment was in some way harmful.
Informed consent is especially important in cases involving experimental treatments.
The patient gives actual consent to a treatment , either orally or in writing. Sometimes doctors provide extensive and elaborate consent forms for patients to sign. It is usually necessary for a parent or guardian to consent to the treatment of a child, unless treatment is required in an emergency situation and the parent or guardian is unavailable to give consent. Sometimes a patient may not wish to accept treatment, or particular kinds of treatment. If the patient is conscious and competent, the patient can refuse.