Randomisation list anonymisation is the masking of the link between a subject and a treatment arm. It supports ICH E6(R2) good clinical practice and blinding. anonym.plus runs offline and keeps the allocation table usable.
When this applies
A statistician shares the allocation table for a check, but the team must stay blind. The sheet ties each subject code to an arm and a kit.
How anonym.plus handles it
- Open the allocation table (XLSX or CSV) in anonym.plus.
- The tool flags subject codes, kit numbers, and any names.
- Local OCR reads a scanned paper list if you add one.
- Confirm the flags and decide what stays blinded.
- Mask the subject-to-arm link, or swap codes for tokens.
- Save the masked table locally with no upload.
What you need to provide
- The table (XLSX, CSV, PDF, or scan).
- An operator: Mask the link, or Replace codes with tokens.
- Optional: a token map held apart from the shared file.
Patient data entity types detected
| Category | anonym.plus entity type | Example |
|---|---|---|
| Subject code | ID | subject 0312 → [TOKEN_A] |
| Kit number | ID | kit KIT-8842 → [KIT] |
| Names | PERSON | entered by N. Roy → [STAFF] |
| Dates | DATE_TIME | allocated 07/03/2026 → [DATE] |
| Site | LOCATION | Site 03, Cardiff → [SITE] |
| Contact | EMAIL_ADDRESS | rand@example.co.uk → [EMAIL] |
Compliance achieved
- Supports the code-breaking discipline in ICH E6(R2) §4.7 — the investigator follows the randomisation procedure and unblinds only as the protocol permits.
- Blinding and the handling of unblinding are design matters set out in ICH E9, Statistical Principles for Clinical Trials.
- The sponsor's duty to code the investigational product so the blind holds sits in ICH E6(R2) §5.13, binding in the UK through SI 2004/1031.
- The list ties a person to a treatment, so it is UK GDPR Art. 9(1) health data, not an administrative table.
- Runs offline — no cloud upload, no data-processor contract; working copies stay under AES-256-GCM.
Anonymise randomisation lists offline — see plans & start free →
Limitations & cautions
Masking the link protects the blind, but a kit number can still trace back through pharmacy records. Decide which columns must be hidden for your blinding plan, and keep the unmasked master under strict access apart from the team.
Frequently asked questions
Why anonymise a randomisation list?
The list maps each subject to a treatment arm. If the team sees it, the blind is broken. Masking the link lets someone check the table’s structure without learning who got what.
Can the team stay blind?
Yes. Mask the arm column or the subject-to-arm link. The shared sheet then shows the layout without revealing the allocation.
Who keeps the real list?
Only the unblinded statistician or pharmacy, under strict access. The master stays on a protected store, apart from the wider team.