Analyst/Medical Writer applicants have rated the interview process at Costello Medical with 3.8 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 50% positive. To compare, the company-average is 50% positive. This is according to Glassdoor user ratings.
Candidates applying for Analyst/Medical Writer roles take an average of 21 days to get hired, when considering 4 user submitted interviews for this role. To compare, the hiring process at Costello Medical overall takes an average of 27 days.
Common stages of the interview process at Costello Medical as a Analyst/Medical Writer according to 4 Glassdoor interviews include:
Skills test: 33%
Group panel interview: 33%
Presentation: 17%
One on one interview: 17%
Here are the most commonly searched roles for interview reports -
I applied online. I interviewed at Costello Medical (London, England) in Oct 2025
Interview
The process was a long and rigorous one. Knowledge is important but they are definitely looking for someone who can apply it in a consultancy context. Which makes sense but I don’t really understand why there’s such a high expectation for an Analyst to already be operating at a Consultant’s level in terms of skill.
Tip: Just really focus on applying your “consulting” skills in the interview i.e. clear communication and time management.
Interview questions [1]
Question 1
1) What does quality mean to you and how do you incorporate this into your work?
2) An instance where you had to handle conflicting timelines?
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?