I was so excited to apply for a role here having checking them online but right now I'm so disappointed and irritated at their level of unprofessionalism. I first applied for a project coordinator role. Bare in mind, this is an entry level role as they stated. Then the HR reached out to me the next day and in her words she said "the team was wondering if you would like to apply for the analyst/medical writer role instead". Obviously I thought, that means they felt I was better suited to the role after going through my CV. I chose to apply for that other role only to get the standard rejection email 5 working days later saying I was unsuccessful. I'm just very disappointed to be honest. For one, this was an entry level role and I have well enough experience on my CV and explained on the cover letter. No feedback, nothing. Whatever anyways
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?