A hybrid system is one where part of the record is electronic and part is on paper. A balance prints a ticket that is stapled into a notebook. An instrument stores raw data while the analyst signs a printout. A result is calculated in software and the approval happens on a paper form.
Hybrid systems are common, often unavoidable, and a reliable source of data integrity findings. The reason is simple: the link between the two halves is usually held together by habit.
Where the risk sits
The electronic part usually has some controls. The paper part has its own. The gap is between them. If a printout is signed but the electronic data behind it can be changed, deleted or re-run, the signature tells you very little about what is now in the system.
Regulators have been clear that, in a hybrid system, the electronic data is part of the record. MHRA's data integrity guidance and PIC/S PI 041 both say you cannot treat the printout as the record and discard or ignore the electronic original when the printout is not a complete and accurate copy of it.
The questions to ask of every hybrid system
- Which part is the record, and is that written down?
- Does the paper copy contain everything needed to reconstruct the result, including metadata such as method, settings and audit trail?
- Can the electronic data be changed after the paper is signed, and would anyone notice?
- Is there a reliable link between each printout and the electronic data it came from, such as a unique identifier?
- Who reviews the electronic data, and how often?
If any of these has no clear answer, that is your list of things to fix.
Make the link explicit
The most useful single control is a link both ways. The printout carries an identifier that points to the electronic record, and the electronic record shows that it was printed and when. With that in place, a reviewer can go from the signed paper to the underlying data and see whether anything happened after printing.
Without it, reconciling the two depends on dates, sample numbers and memory, which is exactly what fails under inspection.
Review the electronic side
Signing the printout is not the same as reviewing the data. For systems where results can be reprocessed or re-run, someone needs to look at the electronic record, including the audit trail, before the result is approved. That review should be risk-based, but it needs to happen. Our guide to audit trail review goes into how to scope it.
Plan the exit
Most hybrid systems are a stage, not an end point. They exist because a fully electronic workflow was not available or affordable when the process was set up. Keep a list of them, rank them by risk, and decide which ones to replace first. The ones that produce release-relevant results and can be reprocessed are usually top of the list.
Our data integrity page covers the wider picture. If you want an independent look at your hybrid systems, get in touch.
Where to go next
Explore GxP Copilot for AI-native validation, TraceDraft for source-traceable clinical documentation, or book a demo to see either on your own data.