In every PLAB 1 sitting, a significant proportion of candidates score well on clinical medicine questions and lose marks on ethics and professionalism. The pattern is consistent enough to be predictable — and preventable.
The reason is straightforward: most PLAB preparation is clinically focused. Candidates spend months learning drug doses, management pathways, and diagnostic criteria. They spend days — sometimes hours — on ethics. The exam does not share this imbalance. Ethics and professionalism questions constitute approximately 8-10% of the exam, and the concepts they test are different enough from clinical knowledge that clinical preparation does not automatically transfer.
This guide covers every high-yield ethics topic with the specific principles and scenarios the exam tests.
GMC Good Medical Practice
Good Medical Practice is the GMC's foundational document. It defines the professional standards expected of every doctor registered in the UK. PLAB questions test whether you understand these standards — particularly when they conflict with clinical preferences or pressure from colleagues.
The four domains: knowledge, skills, and performance; safety and quality; communication, partnership, and teamwork; and maintaining trust. Questions often present scenarios where one domain is being compromised and ask you to identify the correct professional response.
Key principles tested: always act in the patient's best interest; maintain your professional knowledge and skills; be honest and open with patients (duty of candour); raise concerns about patient safety (whistleblowing); and never discriminate against patients or colleagues.
Consent
Valid consent requires the patient to have capacity, the consent to be given voluntarily (no coercion), and the patient to be sufficiently informed about the proposed treatment including risks, benefits, and alternatives.
The exam frequently tests the Montgomery principle: patients must be told about material risks — risks that a reasonable person in the patient's position would want to know about, or risks that this specific patient would consider significant. The old Bolam test (what a responsible doctor would disclose) has been superseded.
Consent scenarios in PLAB: a patient who refuses treatment (you must respect this if they have capacity, even if you disagree), a patient who consents to surgery but the surgeon wants to extend the procedure intraoperatively (cannot proceed beyond the consented scope without new consent unless life-threatening emergency), and consent for procedures on young people (see Gillick below).
Capacity
The Mental Capacity Act 2005 provides the framework tested in PLAB. The five principles are: assume capacity unless proven otherwise; support the person to make their own decision; an unwise decision does not equal lack of capacity; any decision made on behalf of a person lacking capacity must be in their best interest; and the least restrictive option should be chosen.
The two-stage capacity test: Stage 1 — does the person have an impairment of, or disturbance in, the functioning of their mind or brain? Stage 2 — if so, does that impairment mean they cannot understand, retain, use/weigh, or communicate the relevant information?
Capacity is decision-specific and time-specific. A patient may have capacity for one decision and lack it for another. Capacity may fluctuate — assess at the time the decision needs to be made.
The exam consistently tests scenarios where a patient with apparent impairment (intoxication, dementia, learning disability) makes a decision the clinician disagrees with. The correct answer almost always involves assessing capacity formally rather than overriding the patient's decision.
Confidentiality
The default is confidentiality — you do not share patient information without consent. The exam tests the exceptions: where the patient consents to disclosure, where disclosure is required by law (notifiable diseases, court orders, DVLA fitness to drive after patient refuses to stop driving), where disclosure is in the public interest (serious crime, serious communicable disease risk), and where disclosure is necessary to protect the patient or others from serious harm.
The specific scenarios that trip candidates: a patient discloses that they are driving against medical advice (you must inform the DVLA if they refuse to stop, after warning them first), a patient discloses domestic violence (you must offer support but cannot breach confidentiality unless the patient consents or there is risk to children), and a police request for medical records (you cannot disclose without the patient's consent or a court order, except in specific serious crime circumstances).
Gillick Competence and Fraser Guidelines
Gillick competence applies to all medical decisions for under-16s: if the young person has sufficient understanding and intelligence to fully understand the proposed treatment, they can consent to it without parental knowledge. The clinician must assess maturity and understanding for each specific decision.
Fraser guidelines are specific to contraception and sexual health advice for under-16s. A doctor can provide contraceptive advice and treatment without parental consent if the young person understands the advice, cannot be persuaded to involve parents, is likely to have sexual intercourse regardless, their physical or mental health would suffer without treatment, and treatment is in their best interest.
The exam tests scenarios where a 14 or 15-year-old requests contraception. The correct answer involves assessing Gillick competence, not automatically involving parents or refusing treatment.
Safeguarding
Safeguarding questions appear in every sitting. Key points: safeguarding is everyone's responsibility. If you suspect abuse (child or adult), you must act — this overrides confidentiality. Non-accidental injury patterns in children (bruising in non-mobile infants, multiple injuries at different stages, inconsistent history) must be recognised and reported. Adult safeguarding follows similar principles for vulnerable adults.
The exam tests recognition of safeguarding concerns in clinical vignettes and the correct immediate response — which is always to ensure the patient's safety, document your concerns, and involve safeguarding leads.
How to Prepare for Ethics Questions
Read GMC Good Medical Practice — the short version is sufficient. Understand the Mental Capacity Act principles (not just the names — understand how they apply). Know the confidentiality exceptions. Know the Gillick/Fraser distinction. Practise scenario-based ethics questions in your Q-bank.
Ask iatroX provides instant guidance on GMC principles, consent law, capacity assessment, and confidentiality exceptions — grounded in UK legal and ethical frameworks. The Q-Bank includes ethics questions mapped to the MLA content map, with explanations that teach the principle rather than just the correct answer.
Ethics questions are among the easiest marks on PLAB 1 once you understand the principles. They are among the most commonly lost marks when you do not. Invest the time.