Blood Tests, Decoded.

For many markers, yes. For some, no, and the difference is specific to the marker rather than a general rule. That is why some of our panels offer both routes and others are venous only. The lab decides which, based on what they have validated for each panel.

If both are offered, it is a practical choice rather than a clinical one. Finger prick is done at home in a few minutes and posted back. Venous gives a larger sample, which some panels need. If you are squeamish about needles, finger prick is the gentler option. If you have had trouble filling a finger prick device before, choose venous.

For some markers the agreement is very close. A 2025 validation study comparing self-collected capillary plasma with venous plasma found the two lipid profiles essentially identical, with correlations of 0.95 to 0.99 across almost every lipid class (Hameed et al., 2025). For others there is a measurable offset. Capillary haemoglobin tends to read slightly higher than venous, and repeat finger pricks on the same person vary more than repeat venous samples (Patel et al., 2013). This is one of the reasons a full blood count is venous only with us.

Not in practice. The test you actually do beats the better test you put off. A 2025 randomised trial of diabetes screening found that offering a capillary HbA1c rather than sending people for a venous test doubled the uptake, from 38 per cent to 76 per cent, and detected more diabetes and pre-diabetes as a result (Chan et al., 2025).

Two reasons. Volume, because a finger prick yields a small sample and some panels need more than it gives. And validation, because the lab must have shown that the marker performs reliably from a capillary sample before we offer it that way.

The kit matches the route you chose at checkout. Choose finger prick and you get a finger prick kit with lancets and a small collection device. Choose venous and you get a venous kit with tubes for a nurse to use. This is why the choice matters at the point of ordering rather than later.

Under-filling is the usual cause. The instructions in the kit cover warming the hand, letting the arm hang down, and not squeezing the finger, which dilutes the sample with tissue fluid. If a sample cannot be analysed we will tell you and explain the options.

Contact us before your kit ships and we will sort it. Once a kit is on its way, the tubes determine the test, so a switch means a new kit.

Your results come from an accredited laboratory, with every marker reported against its reference range. You will know what each marker measures and what a high or low flag means, in plain English rather than lab shorthand.

Both. The laboratory measures your markers. We add interpretation and support through our own insights engine, so you can see what your pattern means and what to do next.