How to Manage Clinical Trial Sample Chain of Custody
Account for every sample from the participant to the result, and to its disposal.
What a how-to is not
A how-to is SPEQ’s practitioner method, not a procedure. It does not replace your own SOP, it is not a validated approach, and the judgement calls in it belong to your quality unit.
Chain of custody is the record that a sample analysed in a laboratory is the sample taken from a specific participant at a specific visit, and that its condition never left the range the assay requires. It is unusual among trial controls in that it can only be built forwards. A gap discovered later cannot be filled by investigation, because the evidence needed to fill it was the record that was not made.
- 1
Assign a unique identifier at collection and never reuse it
The identifier links the sample to participant, visit and timepoint without disclosing anything that would unblind. Reused or reconstructed identifiers make two samples indistinguishable, and no downstream process can separate them again.
- 2
Record every transfer of custody with person, date and condition
Site to courier, courier to laboratory, laboratory to storage, storage to bench. Each handover names who released, who received, when, and the condition on arrival. An unrecorded handover is a period the sample cannot be accounted for.
- 3
Monitor temperature in transit and act on excursions
Shipments carrying condition-sensitive samples need monitoring and a documented assessment on arrival. An excursion is assessed against the stability data for that analyte — not waved through because the sample looked fine, which is not an assessment.
- 4
Reconcile received against expected on arrival
Compare the shipment against the manifest and query discrepancies immediately. A sample missing for a week is often findable; a sample missing for a month usually is not, and the difference is when someone looked.
- 5
Control aliquoting and derived samples
Each aliquot inherits the chain and carries its own identifier and freeze-thaw history. Aliquots created without that link are orphans — analysable, but not attributable to a participant, which makes the result unusable.
- 6
Document the end state: analysed, stored, returned or destroyed
Every sample has a documented fate, and destruction is authorised against the consent that permitted it. Samples retained for future research need a consent basis that covers that use, and a sample retained beyond its consent is a problem no analysis can fix.
- !Identifiers reused or reconstructed, making two samples permanently indistinguishable.
- !A handover left unrecorded, creating a custody gap that later investigation cannot close.
- !A transit excursion noted and not assessed against the stability data for the analyte.
- !Aliquots created without inheriting the chain, producing results that cannot be attributed to a participant.
How to Manage Clinical Trial Sample Chain of Custody: frequently asked questions
Common questions on manage clinical trial sample chain of custody.
Why can a custody gap not be fixed afterwards?
Because the evidence that would fill it is the contemporaneous record that was not made. You can establish that a sample arrived and was analysed; you cannot establish what happened to it in an unrecorded interval. That is why the chain is built forwards and never reconstructed.
What happens when a shipment arrives outside its temperature range?
It is quarantined and assessed against the stability data for the analytes involved, and the assessment is documented with its conclusion. Some analytes tolerate the excursion and some do not, so the answer is analyte-specific. Accepting a shipment because the samples looked fine is not an assessment.
Can leftover samples be kept for future research?
Only within what the participant consented to. Retention for unspecified future research needs a consent basis that covers it, and where consent is withdrawn the retained samples follow the withdrawal. A sample held beyond its consent basis is a problem no analysis can repair.