What is required when making corrections to reported trial data to ensure traceability?

• A. Erase the original entry after correction.
• B. No traceability is needed.
• C. Corrections must be made with a brief note.
• D. Traceable, and explained if necessary.

Answer: (D)

Corrections must preserve the history of the data. In GCP, you should not erase or obscure the original entry. Any correction needs to be traceable, with who made the change and when, and ideally why the change was made. In practice, the correction is documented so the original value remains visible and the corrected value is linked to it, and an explanation is provided if needed. Electronic systems should maintain an audit trail that records both the original and corrected values. This ensures data integrity and allows audits to reconstruct the data history.