Private Blood Tests in the UK: What to Check Before You Buy

Why this matters

More people are choosing private blood tests, often to get answers sooner, to look at markers (the individual things a test measures, such as a hormone or vitamin) that are not routinely checked, or to track their health over time. The market is varied, and two tests with similar names can differ a great deal in accuracy, scope and usefulness.

Check the laboratory

Look for a laboratory accredited by UKAS (the United Kingdom Accreditation Service) to ISO 15189, the international quality standard for medical laboratories. Accreditation means the lab's methods and quality checks are independently assessed. Reputable providers will name their laboratory and its accreditation.

Check how the sample is taken

Finger-prick tests are convenient, but the small volume of blood and the way it is collected can limit which markers can be measured accurately. A venous sample, taken from a vein in the arm by a phlebotomist (a professional trained to take blood), is the standard used in hospitals and GP surgeries. Ask how the sample is handled and how quickly it reaches the lab, as delays can affect some results.

Check what is measured

Look at the individual markers, not just the name of the package. A test described as a thyroid check may only include TSH (the signal from the brain that tells the thyroid how hard to work), for example, without free T4 (the main thyroid hormone) or thyroid antibodies (signs the immune system is attacking the thyroid). Ask whether the panel, meaning the group of markers tested together, suits the question you are trying to answer.

Check what happens after the results

Good results are explained clearly, with reference ranges (the range of results usually seen in healthy people) and guidance on what to do next. Check whether a clinician reviews results, how abnormal findings are flagged, and whether you can easily share results with your GP. Private tests are not a substitute for NHS care, and your GP will usually want to know what has been tested and why.

Check the full cost

Check whether the price includes collection, for example a home visit or clinic appointment, and whether combining tests into one appointment reduces the overall cost.

What you could do

A few minutes of checking can make the difference between a useful result and a confusing one.

• Write down the question you want the test to help answer before choosing a panel
• Look for UKAS accreditation and a named laboratory
• Plan how you will share and discuss the results with your GP or specialist

This article is for general information only and is not a substitute for medical advice. If you are worried about your health or your results, speak to your GP or specialist team. In an emergency, call 999 or go to A&E.

References:

UKAS, 'Medical laboratory accreditation (ISO 15189)' https://ukas.com/accreditation/standards/medical-laboratory-accreditation

NHS, 'Blood tests' https://www.nhs.uk/tests-and-treatments/blood-tests/