Published: 2nd May 2024 - All information correct at time of publication.
What is Chain of custody?
Chain of Custody (CoC) refers to a series of checks and controls directing the collection, processing, reporting and storage of samples. These processes reduce the potential for samples to be tampered with (deliberately or accidentally) and guarantee that the sample test results reported by the laboratory originate, beyond all reasonable doubt, from a particular donor. Whether it be a blood test, urine test, hair test or other, the chain of custody is there to ensure a robust and reliable collection process.
In short, maintaining CoC means the results reported by the laboratory are admissible in court or employment tribunal, should they need to be.
How is chain of custody maintained?
When a sample is collected, the CoC form is filled out by the collector with the donor (and a witness if desired) present.
The CoC form is used to take down the relevant donor demographic details, the date and time the sample was taken, the collection technician details, any medications declared, the signature of the donor (“consent to test”) for both the on-site test and the back-to-laboratory portion of the analysis and any breath alcohol readings if required.
The form also tells the laboratory which testing to conduct on the sample.
At collection, a copy of the CoC form is given to the donor and a redacted copy is given to the witness. This is to ensure that any personal information given on the form, such as medications/medical history details, are kept confidential to the donor.
Once the sample comes back to the laboratory, there are a number of checks performed by our sample reception staff that ensure that the CoC has been maintained. Once they are happy with the integrity of the sample, they will sign the CoC form to show that they have opened the sample and the sample will go on for further testing.
Where is this information stored?
Once the sample has been checked at our laboratory for integrity and has passed CoC checks, the CoC form is signed by the member of the sample reception team that checked it. The sample is then logged for the required testing and the signed form is scanned into our Laboratory Information Management System where it can be viewed at any stage of the sample analysis process.
If required a copy of the form is also sent to the independent company that conducts our Medical Review testing (MRO).
What does it mean for you?
A chain of custody failure does not mean the results are invalid. What it means is that there is a flaw in the procedure. Under civil law the “balance of probabilities” applies and usually the identity and integrity of the sample can be confirmed through the remaining valid parts of the chain of custody. We will email you to explain the flaw and ask whether you wish us to continue analysis or dispose of the sample.
If there are concerns about the validity of the sample, then please talk to us and we can discuss the implications with you.
Published: May 2nd 2024
Published by: SYNLAB Laboratory Services
Author: Michelle Csete
All information correct at time of publication.
