The lab follows strict quality standards to ensure accurate results. This means that even a small amount of clotting, haemolysis, or an insufficient sample volume may prevent a sample from being fully processed.
We'll explain what's happened and what we'll do next.
The most common reasons
Not enough blood. The lab needs a minimum amount to run all the tests in your package. If there's not enough viable blood, they might still be able to process some of your results.
Unlabelled sample. If your sample tubes aren't labelled correctly, then the lab won't be able to process it. Please ensure that you stick the barcode label directly onto your tube.
Haemolysis. This is when red blood cells break down before testing — usually from blood flow being disrupted when using the autodraw device, or from squeezing the finger too hard during finger-prick collection.
Clotting. Blood naturally starts to clot once it leaves the body. The sample tube in your kit contains an anticoagulant that stops this — but clotting can happen if there’s a delay between collecting your sample and posting it. Or if the blood hasn’t touched the gel at the side of the tube.
Delayed in the post. Samples are most reliable when they reach the lab within a few days. Royal Mail delays around bank holidays or weekends can occasionally mean a sample is no longer viable when it arrives at the lab.
What happens next
If the lab couldn't run all of your tests, we'll let you know. If it's your first go with the test and the majority of your results have failed, the lab will automatically send you a free replacement kit so you can have another go — there's nothing for you to do to request it.
If only a small minority of your tests couldn't be run, you'll get partial results and we'll explain which ones are missing. We'll also give you Thriva credit on your account, which you can use towards the cost of your next test.
How to give yourself the best shot next time
Make sure the incision site is nice and warm before attaching the autodraw device (this makes sure you get decent blood flow which minimises the rupturing of blood cells).
Inverting the yellow tube really gently, not moving it about too much, and placing it in the stabilising plastic holder as soon as possible.
Drinking two glasses of water twenty minutes before your test (this makes your blood flow easier and really helps prevent haemolysis).
If you're using finger-prick lancets, wipe away the first drop of blood before filling the tube (this drop is likely to have been ruptured by the impact of the lancet, so it's best to wipe it away to make sure you have room for all the viable blood).
If you'd rather not retry
If you'd rather not have another go, get in touch and we'll talk you through your options. Depending on your situation, that might be a refund for the test (minus the £15 cost of the kit), a switch to a different sampling method (like our finger prick kits or a venous appointment), or a credit to use later.
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