Abstract
In separate encounters, both the government 1 and a national task force 2 have concluded that it is inappropriate to rely on patients' ‘implied or ‘presumed’ consent. Although interventions such as the centralization of personal data or organ retrieval from dying patients are justified in many circumstances, they cannot be founded on consent unless the consent is valid. This has been reiterated by general practitioners' rejection of any data-sharing system in which the consent of the patient is no more than assumed. 3
Neither presumed nor implied consent are terms that describe a valid form of consent, and their use should be abandoned in clinical medicine.
These must be distinguished from a third term, inferred consent, which denotes the situation where a clinician is assured that all elements of consent are present, thus properly facilitating medical practice.
By asserting that a patient has consented to an intervention, we are referring to the state of the patient's mind. Properly informed, the patient has made a voluntary decision, agreeing to the intervention. Normally, the patient then expresses their state of mind orally or in writing. The caveat that a signature is not necessarily adequate evidence of consent is, in part, based upon the anxiety that the signed form may not be indicative of what the patient truly thinks, i.e. his state of mind. But this expression of consent usually suffices, since there is no practicable alternative.
There are circumstances when it may appear that a person has acquiesced to a situation, but it is not possible to conclude that consent has been given. The unaccompanied non-English-speaking parent who brings his child for polio vaccination sits in silence with the child on his knee, holding open the baby's mouth for vaccination. Once inoculated, the child and father leave. A reasonable observer viewing this could conclude that the father acquiesced to the procedure, satisfying the legal test for implied consent. 4 The father, who has never been vaccinated, now risks contracting polio, infected by the inoculum his child excretes.
The father's ‘consent’ is based on fiction, since consent cannot be provided in the absence of appropriate disclosure. It seems unlikely that he would have consented to this outcome, if informed of his propensity to contract polio as a result of his baby's vaccination.
The observer's conclusion that consent has been provided is incorrect, since it cannot be assumed that the father's action is based upon an informed decision.
Implied consent is a term for a legal device that allows an intervention performed without expressed consent to be recognized as legal. It requires that a reasonable observer would conclude, on the basis of the patient's conduct, that there was acquiescence to the intervention. It has the effect of preventing a person subsequently deny that he consented, even though he did not do so. This stops patients who choose not to express their consent from subsequently complaining that they have not consented to the intervention.
The device of implied consent undoubtedly facilitates practice. The General Medical Council recognizes that for routine investigations, implied consent suffices. 5 However, it qualifies this, ensuring that the practitioner ‘is satisfied that the patient understands’ what is proposed. This describes inferred, not implied consent; where the reasonable observer is satisfied not only that acquiescence has occurred, but also deduces that the patient's state of mind is that of consent. The distinction between implied and inferred is not mere pedantry. The state of a patient's mind, in terms of their attitude to consent, is deduced (inferred) 6 by courts when deciding whether contested consent was valid.
This is completely different from merely relying on a patients conduct to license an intervention, irrespective of the presence of consent.
Implied consent is an unfortunate term, since it indicates that there is consent, where none may exist. In their review, the Organ Donation Taskforce acknowledged that ‘presumed consent’ is a misnomer, and elected to use the term ‘opt out’ 2 when considering the consent systems for organ donation.
However, the widespread false belief that the terms are valid leads some of those who need to legitimize their activity to select implied or presumed consent as the appropriate licence.
The Resuscitation Council view implied consent, erroneously, as a defence 7 for unconsented emergency treatment, contrasting with cancer registries' recognition that it is an insufficient legal basis for cancer database registration. 8
The Information Commissioner uses the term. 9 She ‘does not accept that implied consent is a lesser form of consent’, yet recognizes that some situations require expressed consent.
In the field of sharing patient information, her guidance has been variously translated. In the Welsh NHS, implied consent is given ‘where an individual takes some other action in the knowledge that in doing so he … has incidentally agreed to a particular disclosure of information’. 10 Although designed to legitimize the transfer of information that is essential for clinical care, few patients whose information is thus transferred have sufficient knowledge of the process to form a view on their approval. This can hardly be considered as consent. In Scotland, implied consent is accepted even though ‘explicit consent is best practice’, 11 and should become the norm. This, combined with a warning that the use of implied consent is only acceptable under conditions approaching the threshold of inferred consent, means an abandonment of implied consent, in all but name, by the Scottish Executive when protecting patient confidentiality.
The attraction of using implied consent is that no consent is required. Furness' pithy description 12 of implied consent – ‘provide an information sheet and invite objections’ – is accurate.
‘Presumed’ and ‘implied’ consent should be abandoned within medical practice. ‘Opt out’ is preferable; denoting that what is required is patient acquiescence, not consent.