Informed Consent
Informed consent builds on the basic consent framework by emphasising that patients must receive and understand adequate information about proposed treatments, risks, benefits, and alternatives to make a genuinely autonomous decision, as mandated by the Montgomery ruling.
Key Facts
- Informed consent requires disclosure of material risks, benefits, alternatives, and expected outcomes in language the patient can understand
- The Montgomery test (2015): a risk is material if a reasonable person in the patient's position would attach significance to it, or the doctor should reasonably be aware that this patient would
- Shared decision-making is the model: dialogue between clinician's expertise and patient's values/preferences
- Patients do NOT need to understand every medical detail - but must understand enough to make an informed choice
- Right NOT to know: patients can decline information, but this should be documented
- Clinicians should discuss: what the procedure involves, why it is recommended, what happens without treatment, material risks/complications, alternative treatments
- Consent for research has additional requirements: voluntary, right to withdraw, no impact on standard care (Declaration of Helsinki, GCP)
- Language barriers: professional interpreter must be used; family members should NOT routinely interpret for consent
Overview
Key Facts
Informed consent goes beyond simple agreement to treatment. It requires a genuine exchange of information enabling the patient to make an autonomous choice. The Montgomery ruling transformed UK consent law from a paternalistic model to a patient-centred approach.
Pre-Montgomery vs Post-Montgomery
- Pre-Montgomery (Bolam/Sidaway): doctors disclosed what a reasonable body of doctors would disclose (doctor-centred)
- Post-Montgomery (2015): doctors must disclose what a reasonable patient would want to know (patient-centred)
- The patient's perspective is now central to determining adequacy of disclosure
Information to Disclose
- Nature and purpose of the proposed treatment/investigation
- Material risks and benefits
- Alternative treatments (including no treatment)
- Expected outcome and recovery
- What the patient can expect during and after the procedure
- Answer the patient's questions honestly and fully
Barriers to Informed Consent
- Health literacy: approximately 43% of UK adults cannot fully understand health information
- Language barriers
- Cognitive impairment
- Emotional distress at time of consent
- Power imbalance between doctor and patient
- Time pressures in clinical practice
- Complexity of medical information
Clinical Presentation
Practical Approach to Informed Consent
- Check patient's understanding and prior knowledge
- Explain diagnosis and proposed treatment in plain language
- Discuss material risks using absolute numbers where possible
- Discuss benefits and expected outcomes
- Explain alternatives (including doing nothing)
- Invite questions
- Ensure understanding (teach-back method)
- Allow time for reflection
- Document the discussion
- Patient signs consent form (if applicable)
Communicating Risk
- Use absolute risk rather than relative risk
- Use consistent framing (e.g. '2 in 100' rather than '2%' or '1 in 50')
- Visual aids (icon arrays, risk charts) improve understanding
- Avoid minimising language ('small risk', 'rarely happens')
- Context: compare to familiar risks where helpful
- Patient decision aids can support the process
Special Considerations
- Elective procedures: more time available; expect comprehensive discussion
- Emergency procedures: abbreviated but essential consent; document constraints
- Procedures under anaesthesia: consent must be obtained well in advance
- Procedures with trainee involvement: disclose if trainee will perform part of procedure
- Innovative/experimental treatments: higher standard of disclosure
Differential Diagnosis
| Standard | Test | Implications |
|---|---|---|
| Bolam (1957) | What a reasonable body of doctors would do | Paternalistic; largely superseded |
| Sidaway (1985) | Doctor decides what to disclose (with therapeutic privilege) | Doctor-centred |
| Montgomery (2015) | What a reasonable patient would want to know | Patient-centred; current standard |
| Canterbury v Spence (1972, US) | Material risk = would affect patient's decision | Influential US precedent |
Diagnosis / Investigation
Quality Assessment of Consent
- Was information provided in advance (not just at time of procedure)?
- Was information in the patient's language and at appropriate health literacy level?
- Were decision aids or written materials used?
- Was there opportunity for questions?
- Was the patient's understanding verified (teach-back)?
- Was the consent discussion documented (not just the form signed)?
- Were patient's specific concerns addressed?
- Was the consent obtained by an appropriately qualified clinician?
Management
Improving Informed Consent in Practice
- Decision aids: condition-specific tools helping patients weigh options (available via NHS, NICE, specialty societies)
- Written information: pre-procedure leaflets sent in advance
- Teach-back method: 'Can you tell me in your own words what we discussed?'
- Cooling-off period: time between information provision and procedure
- Professional interpreters: mandatory for non-English speakers; telephone interpreting services available 24/7
- Easy Read materials: for patients with learning disabilities
- Audio/visual aids: videos explaining procedures
When Informed Consent is Particularly Important
- Procedures with significant risk of complications
- Treatment with uncertain benefit (e.g. some cancer treatments)
- Procedures with cosmetic implications
- Irreversible procedures (e.g. sterilisation, amputation)
- Research participation
- Screening (informed choice about participation)
Therapeutic Privilege
- The Montgomery ruling acknowledged a very narrow 'therapeutic exception' - withholding information if disclosure would cause serious harm to the patient
- This exception is extremely narrow and rarely justified
- Does NOT include withholding information because the doctor thinks the patient would refuse treatment
Prognosis
- Good informed consent practice improves patient satisfaction, reduces complaints, and reduces litigation risk
- The Montgomery ruling has led to significant changes in consent practice across the NHS
- Ongoing challenges: time pressures, health literacy, cultural differences
- Digital consent platforms and decision aids are improving the process
- Training in communication skills and shared decision-making is now embedded in medical education
Other Relevant Information
Montgomery v Lanarkshire: Key Facts
| Element | Detail |
|---|---|
| Year | 2015 |
| Court | UK Supreme Court |
| Facts | Diabetic mother not informed of risk of shoulder dystocia with vaginal delivery |
| Ruling | Doctors must inform patients of material risks |
| Test | Risk is material if reasonable person in patient's position would attach significance to it |
| Impact | Shifted UK law from Bolam (doctor-centred) to patient-centred disclosure |
Communicating Risk - Recommended Format
| Risk Level | Natural Frequency | Descriptor |
|---|---|---|
| Very common | >1 in 10 | 'More than 1 in 10 people are affected' |
| Common | 1 in 10 to 1 in 100 | 'Between 1 and 10 in every 100' |
| Uncommon | 1 in 100 to 1 in 1,000 | 'Between 1 and 10 in every 1,000' |
| Rare | 1 in 1,000 to 1 in 10,000 | 'Between 1 and 10 in every 10,000' |
| Very rare | <1 in 10,000 | 'Fewer than 1 in 10,000' |