Manufacturing and quality

Quality Control interview questions

Analytical and microbiological testing against defined specifications.

6 questions, each with a worked answer

What would you do after an out-of-specification laboratory result? Fundamentals Concept
How do accuracy and precision differ in analytical testing? Fundamentals Concept
Why does an OOS result not disappear after a passing retest? Intermediate Scenario
How do specificity and selectivity matter for analytical methods? Intermediate Scenario
When should QC methods be revalidated? Advanced Scenario
How do you distinguish laboratory method variation from batch variation? Advanced Scenario

About Quality Control

Quality control tests raw materials, intermediates and finished products against defined specifications. It includes analytical chemistry, bioassays and microbiology, run with validated methods under GMP. Out-of-specification and out-of-trend results trigger formal investigations.

QC data are what a release decision rests on, so accuracy and data integrity are essential.

Fundamentals: 2
Intermediate: 2
Advanced: 2

What these questions test

Perform controlled analytical testing: Obtain traceable testing results and investigate anomalies.

References

Current Good Manufacturing Practice (CGMP) Regulations. U.S. Food and Drug Administration. fda.gov/drugs/pharmaceutical-quality-resources/current-good-manufacturing-practice-cgmp-regulations.
fda.gov/regulatory-information/search-fda-guidance-documents/investigating-out-specification-oos-test-results-pharmaceutical-production-level-2-revision.
fda.gov/regulatory-information/search-fda-guidance-documents/q2r2-validation-analytical-procedures.

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.