I passed CV screening and went about the first round (proofreading + writing assessment). They gave me a week for that; the writing assessment involved answering some questions based on a research article, and the proofreading assessment involved making 50+ edits to an article and writing a 300 word summary of an article in 1 hour.
The recruiter + some others review it, and I was then invited to the final stage interview in Boston. It was further away, so I did it virtually -- 15 min presentation w/ questions to an analyst + senior analyst, you present on a report with a similar topic to the writing assessment, and 45 min behavioral interview with a more senior leader. Interview ran long (they ask a lot of presentation followups) and I ended 25 minutes past the timeframe haha, but all good I hope. Interviewers were all sweet and gave gentle feedback/broadened some of your responses in the moment, if needed. It was a bit tough, but make sure to prepare well, and you got this! Still waiting to hear back and will update the result later.
Interview questions [1]
Question 1
Tell me about yourself/why this role? Why Costello specifically?
What would you do if a client told you that you made a mistake in your work?
What kind of culture are you looking for in your workplace?
A time you managed multiple deadlines?
Your background in science and/or writing?
Make sure to ask your interviewers some good questions!
I applied through an employee referral. I interviewed at Costello Medical (London, England) in Feb 2026
Interview
1st stage: submitting CV
if you pass the CV screen: Timed proofreading test and an assessment on a paper on drug discovery
The timed proofreading test was very challenging and required attention to detail and staying cool underpressure.
I applied through an employee referral. I interviewed at Costello Medical in Nov 2025
Interview
Starts with CV and Cover letter. Then a scientific writing and timed proofreading assessment. Finally, a presentation and Behavioural + Technical interview, followed by an interview with the Head of Department.
Interview questions [1]
Question 1
Why Costello? Why are you a good candidate? How would you handle conflicting feedback? How do you deal with mistakes? Do you have experience with scientific communication?