Gonville & Caius Cambridge Medicine Interview

Gonville and Caius College — universally known as Caius — is one of Cambridge’s most distinguished medical colleges and one of the oldest institutions in the university. Caius has produced more Nobel Prize winners in Medicine and Physiology than any other Cambridge college, and its Medicine interviews reflect the scientific rigour of an institution with that heritage. Caius Medicine supervisors are looking for students who can reason precisely about biological and biochemical problems, engage with data and experimental results critically, and bring genuine scientific curiosity to questions at the edge of their knowledge. Candidates who arrive prepared primarily to talk about clinical work experience will find Caius interviews more demanding than they expected. Written answers to questions like these are in the Medicine pack, £180.

Cambridge Medicine, like Oxford, is a pre-clinical degree: the first three years are almost entirely basic science, and clinical training begins only in Year 4. Caius supervisors are assessing whether you will thrive in that environment — whether you have the scientific depth, the mathematical fluency, and the intellectual curiosity to engage with biochemistry, physiology, pharmacology, and neuroscience at undergraduate level. Motivation for clinical practice matters, but it is your scientific thinking that will determine your interview performance.

The Caius Medicine Interview Format

Cambridge Medicine applicants typically have two interviews, and those applying to Caius will interview there and at a second college through the pooling process. Caius Medicine interviews last approximately 25 to 35 minutes and are problem-led: supervisors present biological scenarios, experimental data, or scientific questions and observe as you reason through them. You will be expected to think aloud, engage with hints when offered, and demonstrate that you can extend your reasoning beyond the immediate question into deeper scientific territory.

Caius uses the UCAT to shortlist Medicine candidates. Strong performance on UCAT Section 2 — which tests scientific knowledge and application — is particularly important for a Caius interview invitation. The UCAT also assesses writing skills in Section 3, and the ability to construct a clear, nuanced argument about a scientific or medical claim is directly relevant to what Caius supervisors assess.

Preparing for Caius Medicine Interviews

Build strong conceptual foundations in the biological sciences that underpin medicine: biochemistry (particularly enzyme kinetics, metabolism, and cell signalling), physiology (cardiovascular, respiratory, and renal systems), genetics, and pharmacology at a basic level. You do not need undergraduate knowledge in these areas, but you should understand the A-level content thoroughly at a mechanistic level — being able to explain not just what happens but why, at the level of molecules and cells.

Practise interpreting experimental data. Caius Medicine interviews frequently involve graphs, tables, or brief descriptions of experimental results. You should be able to identify what a graph is showing, what the pattern suggests, what confounds or alternative explanations might be present, and what further experiment would help clarify the picture.

Engage with medical ethics at an accessible level. Caius supervisors do not expect formal knowledge of bioethics, but they do ask candidates to reason about ethical dilemmas. Being familiar with the four principles framework — autonomy, beneficence, non-maleficence, justice — and being able to apply it to novel scenarios is useful preparation.

Example Caius Medicine Interview Questions

• Here is a graph showing enzyme activity against substrate concentration. Explain its shape.
• Why does the heart pump blood through two separate circuits? What would go wrong if it used only one?
• A new drug reduces blood pressure in a small clinical trial. What would you need to know before recommending it for widespread use?
• How does the body respond physiologically to severe blood loss?
• What is the difference between an infectious disease and a genetic disease? Are these categories always distinct?
• A patient refuses a recommended treatment. Under what circumstances, if any, might a doctor be justified in overriding this refusal?

For free samples in nine subjects and the full expert packs at £180, see our Cambridge Medicine interview questions resource.

The hint is part of the test

The format above mentions engaging with hints, and that is worth taking literally: at Caius the prompt a supervisor offers mid-problem is not a rescue, it is the next part of the question. A candidate who takes the hint and keeps reasoning out loud scores better than one who takes it and produces the answer in silence, because the second version tells the supervisor nothing about what just changed in their thinking.

The Medicine pack is built in that shape. Each of its ten questions is given on its own first, then a layer headed Hints holding the prompts an interviewer would actually offer, then a full written answer — so the moment of being helped is something you can practise rather than meet for the first time in the room. Medicine is not one of the nine subjects with a free sample, so there is no trial chapter to read first.

The science half is only half of it. The same pack carries the ethics scenarios a Cambridge panel actually raises — euthanasia and patient confidentiality among them — and those are marked on whether you can hold two duties in view at once rather than pick a side quickly. Caius supervisors move between the two registers without warning, and the pack is ordered so that you do too.

Frequently Asked Questions

What Does a Full Pack Answer Actually Look Like?

Caius supervisors say they are testing scientific reasoning rather than recall, and the clearest way to show what that means in practice is to work through one full question from the Medicine pack exactly as it appears there: posed on its own first, then a Hints section for anyone who gets stuck, then the complete answer with nothing skipped.

Take one of the pack's early questions: someone's total plasma volume measures 3.3 litres, and they drink half a litre of a beer that is 4% alcohol by volume. Treat the beer as no denser than water, hold that plasma volume steady, and assume none of the alcohol has yet moved out of the blood into other tissues. What concentration of ethanol does that leave in the plasma?

Hints

The pack keeps its Hints layer deliberately thin, closer to what a supervisor might offer a candidate who has gone quiet partway through an answer than to a worked solution in miniature. For this question, the hint is one line: name the equation linking concentration to moles and volume, then work out which of those two quantities is already given and which one takes an extra step to reach first. It does not say which volume to use, and that omission turns out to be the entire question.

Start with the alcohol itself. Four percent of half a litre (500 mL) is 20 mL of ethanol by volume — a simplification real brewing chemistry complicates slightly, but one the question explicitly licenses by fixing the density assumption. Treating the beer as no denser than water turns that 20 mL into a mass of 20 g. Ethanol's molar mass works out to about 46 g/mol, so 20 g of it comes to roughly 0.435 mol — the number both possible answers below will use.

The concentration equation still needs a volume to divide that 0.435 mol by, and this is where the question's precision matters more than it first appears to. In real pharmacology, alcohol genuinely does distribute through something close to a person's total body water rather than staying confined to plasma — a fact taught alongside drug dosing calculations, and one this same pack uses in an earlier question about a 75-kilogram patient's body water. Total body water for an adult of that size comes out at around 45 litres. Reaching for that figure here and dividing 0.435 mol by 45 litres gives roughly 0.0097 mol/L, about 9.7 mM. That answer is wrong, but not through a slip in the arithmetic: it applies real physiology the question has specifically excluded. The question states, in the same sentence as the beer, that plasma volume stays constant and that none of the ethanol has left the bloodstream, which rules out spreading it through the whole body at this stage. The volume it actually wants sits earlier in the same sentence: 3.3 litres of plasma.

Dividing the same 0.435 mol by 3.3 litres instead gives approximately 0.132 mol/L, or 132 mM — about thirteen and a half times more concentrated than the whole-body version, and the figure the pack's own answer reaches. Both routes use correct chemistry and correct arithmetic; only one of them uses the volume the question actually specifies. That gap is what a supervisor is listening for when a candidate talks through this kind of problem out loud: not whether they remember that ethanol distributes through body water in general, but whether they notice when a question has deliberately fenced that generalisation off.

A Caius supervisor would likely not stop there. The natural follow-up is what happens after an hour, once the liver starts breaking the ethanol down at roughly a fixed amount per hour rather than a fixed proportion of what remains — a different kind of process from the concentration calculation above, and exactly the sort of second step interviewers use to check whether a candidate's reasoning survives once the tidy starting assumptions are taken away.

That is the shape of all ten questions in the Medicine pack: each one stated once, a short Hints line if it is needed, then a complete answer worked all the way through, across 22 pages, for £180.