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Pseudonymize documents and keep the key separatePage 1 of 3
Guide · pseudonymize documents

Pseudonymize documents and keep the key separate

Pseudonymization replaces identities with stand-ins while a separate key lets authorised people link them back. Re-Doc replaces each identity with one consistent synthetic value and gives you the full change list as a CSV, which can serve as that key if you store it apart from the documents.

Upload a file, first 10 pages freeSee pricing
Example

What Re-Doc changes

Orange boxes are what Re-Doc finds on its own. Text-based files keep their layout, and each real value is swapped for a realistic synthetic one.

1. Your documentvisit_note.pdf
Clinical Visit Note
Site 04 · Visit 3
ParticipantJoseph Mensah
Participant IDS04-0219
DOB11 Mar 1962
InvestigatorDr. Lena Brandt
FindingBP stable
2. Safe to sharevisit_note_safe.pdf
Clinical Visit Note
Site 04 · Visit 3
ParticipantDaniel Owusu
Participant IDS04-7743
DOB02 Aug 1961
InvestigatorDr. Mia Keller
FindingBP stable
What to replacePage 2 of 3
Checklist

What to replace, and what to keep

Usually replaced

  • Direct identifiers: names, IDs, contact details
  • Dates tied to the person: birth and visit dates if required
  • The same identity everywhere: one consistent replacement per person
  • Keep the CSV change list separately: it is the key that links back

Usually kept

  • The clinical or business content
  • Relationships between people in the document
  • Layout and format
Tip

Under GDPR, pseudonymized data is still personal data for whoever holds the key. Store the CSV with stricter access than the documents.

How it works

Three steps

  1. STEP 1

    Upload

    PDF, Word, TXT, scan or photo, up to 50 MB. Sign in with Google; the first 10 pages are free.

  2. STEP 2

    Review

    Re-Doc highlights every change. On scans you can add or remove boxes; for any file you can describe what to keep or remove in plain words.

  3. STEP 3

    Download

    Get the safe copy in the same format you uploaded, with the layout unchanged.

QuestionsPage 3 of 3

Frequently asked questions

01Is this pseudonymization or anonymization?
If you keep the CSV change list, the output is pseudonymized. If you delete the list and nothing else links back, it moves towards anonymization, subject to your own risk assessment.
02What does the CSV contain?
Each original value next to its replacement and its type, for every change in the document.
03Is the replacement consistent?
Yes, within a document each person or value keeps the same replacement.
04Is this legal advice?
No. Check with your data protection officer how pseudonymized data must be handled in your case.
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