Consent may be given in different forms. The details of the agreed procedure and risks are then recorded on a form, which may then be signed by the patient as evidence that the patient agrees. From the court's point of view the fact that the patient has signed the consent form and therefore expressly agreed that the nature and extent of the operation has been explained, would be strong evidence to defend any action for trespass to the person. The Department of Health provides advice and model forms of consent. Implied consent is where non-verbal communication by the patient makes it clear that consent is given. For example, after receiving appropriate information, a patient rolls up their sleeve and holds out an arm for their blood pressure to be taken, or the patient opens their mouth as the nurse waves the thermometer in the air.