I applied online. The process took 2 weeks. I interviewed at Costello Medical in Jun 2024
Interview
It's a lot of work for not a lot of opportunity. Much like lots of entry level position, Costello know people are desperate for a job so have applications that take hours before you're reqarded with an interview.
I got to the assessment stage after the cover letter and CV have been approves. They say you get feedback on the written assessments, but it's half a sentence with no guidance on how to improve: I was given two strong positives of my application with one negative, that my answers were 'a little too brief', given that the written answers all had maximum word limits, this feels like a cop-out. Asking about applying again I was advised to 'evidence how I've developed further' in my CV and cover letter... not sure how I do that when their feedback was so limited.
I was originally reticent about applying because of the terrible reviews on here from ex-staff, but it was such a perfect job for me and a perfect fit I went for it anyway. I wish I hadn't. The application process doesn't make you feel valued and the amount of work they expect (don't expect the assessment exercises to take less than 3 hours minimum) to possibly earn an interview (that you have to prepare an additional presentation for) is likely a clue of what they're like to work for. I imagine the interview process is intentionally designed to weed out people who won't work late and work foe free.
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?