In electronic trial data handling, which statement reflects a requirement to protect data integrity?

• A. All trial data must be encrypted at rest.
• B. Backups are optional if data integrity is maintained.
• C. Data changes may be deleted after processing.
• D. Ensure that data changes are documented and that there is no deletion of entered data.

Answer: (D)

Maintaining data integrity means keeping trial data accurate, complete, and traceable throughout the study. Requiring that all data changes are documented and that entered data are not deleted creates an auditable record of what happened to the data, when, and by whom. This prevents hidden alterations or loss of information and supports verification of findings, which is essential in good clinical practice. Encryption at rest protects confidentiality but doesn’t by itself guarantee data integrity. Treating backups as optional risks unrecoverable data loss and doesn’t directly ensure integrity. Deleting data after processing erases historical records and undermines the trustworthiness of the dataset.