The lab has very precise standards for what they can process, and a small amount of clotting, haemolysis or volume can mean a sample doesn't make the cut.

We'll explain what's happened and what we'll do next.

Not enough blood. The lab needs a minimum amount to run all the tests in your kit. Smaller samples can sometimes give partial results, but most tests need a full tube.

Unlabelled sample. If your sample tubes aren't labelled, then the lab won't be able to process it. Please ensure that you stick the label on your tube.

Haemolysis. This is when red blood cells break down before testing — usually from being shaken in transit, or from squeezing the finger too hard during collection. Haemolysed samples can throw off certain markers (like potassium and LDH) and the lab won't release results from one.

Clotting. Blood naturally starts to clot once it leaves the body. The little tube in your kit contains an anticoagulant that stops this — but it only works if the blood is mixed with it gently and quickly. If a sample arrives clotted, the lab can't process it.

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 push a sample past its window.

If the lab couldn't run all of your tests, we'll let you know by email and follow up in the app. If it's your first go with the test, 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. Just keep an eye on your email and the app inbox.

If only some of your tests couldn't be run, you'll get partial results and we'll explain which ones are missing.

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 Autodraw kit or a venous appointment), or a credit to use later.

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