Amendment 3 versus amendment 2
A protocol amendment is issued as a complete new document. The summary of changes is written by the sponsor and is usually accurate about the big items: a changed dosing schedule, a new inclusion criterion. It is less reliable about the small ones: a changed visit window, a re-worded endpoint, a corrected table.
Who needs the list
- Sites, to update their procedures and re-consent participants where needed.
- Monitors, to check that the changes were implemented.
- Ethics committees and IRBs, to review what they are being asked to approve.
- Sponsors, to confirm that the submitted version matches the approved version.
Informed consent forms
Consent forms are revised often and translated into several languages. Comparing each revised form against its previous version, per language, shows exactly which paragraphs changed and therefore which participants need to be re-consented. The comparison aligns content by paragraph, so an inserted paragraph does not make every later page look changed.
Reproducibility
The comparison is deterministic. The same two PDFs always produce the same change list, which is what a regulated record requires. Enterprise deployments run inside the sponsor's or CRO's own infrastructure.
Try it on your own documents. Upload two versions on the homepage. Documents up to 30 pages need no account, and nothing is stored.
Industry page: PDF comparison for clinical research