Test taken: Natural Sciences Admissions Assessment (NSAA)
Number of interviews: 2
Time between interviews: 1-2 hours
Length of interviews: c.30 mins 
Online interview: Yes

My first interview started with one personal statement question - I think just to get me talking - and then straight into content questions about Biology and Chemistry. Each question thread started with something I knew (e.g. cell structure) and then went further into perhaps why this was the case, what alternative systems could work, why they would/would not be good etc. So extending the thread into unknown territory and asking me to use my existing knowledge to think about these new ideas. I did get stuck at various times and just said this to the interviewers - once it was due to a technical issue, but the other times I was properly stuck but they always helped me through it, rephrasing the question or asking why my idea would/would not work. So talk to them, if you're stuck!

My second interview started with a discussion about my personal statement which then led to Biology and Maths questions. The question thread was the same as above (starting with a question I knew the answer to from A-level, then going further and further into new ground, asking me to apply my knowledge). We also discussed a bit of experimental design, and maths - both calculations (again application using A-level knowledge) and describing a graph.

I prepared all of the 'soft' stuff - so why I wanted to study NatSci, why not VetMed (my application was very animal-focused!), why Trinity Hall (although I doubt they will ask this). I also 'revised' my personal statement by going through and identifying any areas where I thought they were likely to ask further questions (e.g. I had a section on biomimicry, so I thought they might be likely to ask me for an example of this, or the usefulness/importance of it) and then prepared answers to these. This helped in the interview basically by preventing me from panicking at the start - by having answers prepared for the first few questions I could start to get on a roll without being stuck or lost for words.

For the scientific content side of things, I googled my interviewers to find their field of interest and then brushed up my knowledge of this area but *only to the level I had been taught (so A-level, for me)*. I personally don't recommend learning extra stuff in their area as they're aiming to push you into unknown territory and then see how you think, so by learning more you just push that borderline into even more unfamiliar waters! I was lucky enough to have family friends who gave me practice interviews, but this was definitely a bonus not a necessity. It probably helped a little in giving me practice answering questions I didn't know the answer to (and working them through), but wasn't always helpful - one of them gave a fairly non-Oxbridge interview which mostly served to worry me! So, I'd say use them if you are offered them but if not, don't worry, and remember to take them with a little pinch of salt as they may not be a true recreation of the real thing.

Revised all of the content as per the NSAA syllabus (available online), then did past NSAA and BMAT questions to practice the types of questions and how to tackle them.

My biggest piece of advice is to talk! They don't know what you know/are thinking until you tell them. So talk through every step of your thinking. And if you're stuck, talk through your existing knowledge as this can help you to see the way to the answer/correct line of thinking. Ask if you're stuck or unsure! They may say no (in which case you haven't lost anything) but they often can help, by rephrasing the question or asking you to consider a different aspect. This is totally normal and fine. If you go down an idea trail and you realise it wouldn't work, say this! Say something like 'I've just realised this wouldn't work because XXX' - tell then you've thought about it and you know why it wouldn't work - then try to offer an alternative (rather than just stopping talking when you realise it wouldn't work). Don't be put off if they cut you off to ask another question - they're just trying to get as much out of the time as possible, and this isn't necessarily a bad thing. You may have already said all they were looking for!