Clinical and regulatory

Clinical Trial Design interview questions

Endpoints, populations, controls, randomization and feasible study plans.

9 questions, each with a worked answer

What is the purpose of randomization in a trial? Fundamentals Concept
How would you select a primary endpoint? Advanced Scenario
How would you distinguish a superiority trial from a noninferiority trial? Intermediate Concept
What is an estimand and why must it be defined before analysis? Intermediate Scenario
What is the purpose of allocation concealment? Advanced Concept
How do missing outcomes affect interpretation of a randomized trial? Advanced Troubleshooting
How would you select between superiority, noninferiority and equivalence trial objectives? Intermediate Troubleshooting
Enrollment is lower than expected and event rates change. What design implications would you evaluate? Intermediate Troubleshooting
Design a strategy to limit bias when blinding is impossible for a behavioral intervention. Advanced Practical

About Clinical Trial Design

Clinical trial design decides how a study will answer its question: who is enrolled, what they receive, what is measured and how results are analysed. Key choices include endpoints, control groups, randomisation, blinding and sample size. A good design balances scientific rigour with ethics, cost and what patients and sites can realistically do.

Weak design cannot be rescued by analysis afterwards.

Fundamentals: 1
Intermediate: 4
Advanced: 4

What these questions test

Write clinical protocol elements: Align objectives, populations, endpoints and analyses.

References

Practice material written by TheBench.Bio and checked against the references above, reviewed October 23, 2026. Written to practise with, not collected from real interviews.