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A medium Data Modeling mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.

Domain
Data Modeling
Difficulty
medium
Seniority
mid

Interview Prompt

A pharmaceutical company runs multi-site clinical trials where a patient can move between treatment arms during the study, through crossover or a dose reduction. Design a schema for the safety team that stores adverse event reports and attributes every event to the arm the patient was actually on when the event was reported, so per-arm safety rates stay correct even after patients switch. The team also needs to reconstruct, for any date, which arm and dose a patient was on for audit.

How This Interview Works

  1. Read the vague prompt (just like a real interview)
  2. Ask clarifying questions to the AI interviewer
  3. Write your data modeling solution with real code execution
  4. Get instant feedback and a hire/no-hire decision

Related

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