Members are advised to refer to the GOC’s consent guidance here.
Also copied below is the relevant section from the GOC document:
3.1 Obtain valid consent before examining a patient, providing treatment or involving patients in teaching and research activities. For consent to be valid it must be given:
3.1.2 By the patient or someone authorised to act on the patient’s behalf.
3.1.3 By a person with the capacity to consent.
3.1.4 By an appropriately informed person. Informed means explaining what you are going to do and ensuring that patients are aware of any risks and options in terms of examination, treatment, sale or supply of optical appliances or research they are participating in. This includes the right of the patient to refuse treatment or have a chaperone or interpreter present.
3.2 Be aware of your legal obligations in relation to consent, including the differences in the provision of consent for children, young people and vulnerable adults. When working in a nation of the UK other than where you normally practise, be aware of any differences in consent law and apply these to your practice.
3.3 Ensure that the patient’s consent remains valid at each stage of the examination or treatment and during any research in which they are participating.’