EDC: running studies

Audit trail

What is recorded, how integrity is checked, export.

Every action in a study is recorded: who, when, from which address, old and new value, reason. Records cannot be changed or deleted, not even directly in the database.

Integrity check

Each study's records are linked by a SHA-256 hash chain: every record carries the fingerprint of the previous one. If someone alters a record behind the system's back, the chain breaks. The “Verify” button on the audit page recomputes the chain; the same check runs every night and a failure shows on the administrator's desk.

Export

“Download CSV” exports the study's audit trail for the archive or an inspection. It opens in Excel.