Your Wearable Guesses. Your Blood Knows.

What can a blood test see that a watch cannot?

A watch measures you from the outside and calculates the rest. Every number it shows you, from sleep quality to recovery, is worked back from a handful of surface signals, so it is an estimate. A blood test does no calculating: it measures how much of a given substance is present in a sample of your blood. One tells you that something has shifted. The other tells you what, and by how much.

Consider what your watch is actually doing. It reads your pulse by shining light through your skin and timing what bounces back. From the rhythm of those beats it estimates your stress. From that, plus how much you move overnight, it estimates your sleep stages. Each step is a reasonable calculation built on the one before it, and every one of them is made from outside your body. A blood test starts somewhere else entirely: it takes the sample and measures the thyroid hormone itself.

Four layers, not two

There are four steps here, and most health products stop at the second. Your watch estimates. An app or an AI finds patterns in those estimates. A blood test measures what is actually present. A functional report then reads those measurements as a group, and says something about how a body system is holding up.

What is a functional optimal range, and how is it different from a normal range?

The standard range is the one your lab compares you against, worked out from lots of ordinary people. The optimal range is tighter, and shows where the number usually sits in people who are well. Your result can be normal on the first and still be outside the second.

Here are six results from an example report. Five of them sit comfortably inside the standard range, so a normal lab report would say nothing at all. Only one is inside the optimal range.

Take TSH, the main thyroid result. At 2.55 it sits well inside the standard range of 0.40 to 4.50, so an ordinary report would show nothing. Against the optimal range of 1.00 to 2.00 it is high, and in this example it is the one number putting thyroid near the top of the list. That is not a diagnosis. It is a place to look.

Seven bands, not three

Results are not just sorted into good, borderline and bad. Each one is placed on a scale of seven bands, and the scale works both ways, because a number can be too low as easily as too high.

What does an ODx functional health report contain?

Five things, every time: each result on the seven-band scale with both ranges, a score for each body system along with the results behind it, a short list of what needs the most attention, a comparison with your last test, and a list of the tests you did not have. It runs to about 24 pages.

Which results appear depends on the panel you booked. The five parts above never change, and that is the bit worth knowing before you order. The report is generated for any blood panel containing non-infectious markers, not only the three ODx panels: thyroid, fertility, metabolic, organ function, nutrition, sport and anti-ageing panels all produce one.

1. A score for each body system

Where there are enough results to work with, the report scores how likely each body system is to be struggling, and then shows you exactly which results produced that score. The second half matters more than the first: your results are read as a group, not as a row of separate verdicts.

Example only. Anything above 50% gets its own page in the report, written in plain English, showing which results caused it: for the kidney score here, BUN up, creatinine up, BUN:creatinine up, eGFR down.

2. What needs attention first

The whole report then boils down to a single page: what needs the most attention, in order. If you read nothing else, read this page.

3. This test against your last one

If you have tested before, every result is shown next to last time, and the report counts how the whole picture has moved. In this example the two tests are seven weeks apart:

Eight more results in the optimal band, one fewer in alarm, and two more in the high band. That last number is the useful one. A real report moves both ways at once, and seeing what went the wrong way is the whole point of comparing.

4. The tests you did not have

Each score also lists the tests that would have made it sharper but were not in your panel. A thyroid score built on one result will say so, and name what a fuller thyroid picture would need. It is an honest account of what the report could and could not see.

5. Old results still count

You can load blood tests you have had in the past into the system and have them read the same way, so your trend does not start from scratch. Results you had forgotten about become the beginning of it.

What a blood test cannot tell you

A blood test shows what was in your blood on the morning you gave the sample. It does not know what came before, what started it off, or what has been keeping it going, and the answer is usually in one of those three.

A doctor working through a problem that will not go away wants three things. What came before it: your family, illnesses you have had, what you have been around for years. What set it off: an infection, a treatment, a move, a job. And what is keeping it going now. A blood test speaks to the third one. That is a third of the picture, which is why the report is something you take to an appointment rather than something that replaces one.

Anything the report flags belongs with a doctor, who can read it next to your own history and examine you. Epicentre does not prescribe or treat, anywhere: not at a branch, not by phone. What we can do is walk you through the report in an ODx Expert Session, where a specialist goes through it marker by marker and helps you build a practical plan around food, movement, sleep and when to retest. That session is free with any Epicentre functional health test of R1,500 or more, and R300 otherwise. Where medical care is needed, the branch team will make a referral based on where you are and what you need.

How app developers use functional reports to give their users better answers

If you are building a health product, the quality of the advice it gives depends on the quality of the lab data behind it. A standard pathology report hands your product a result, a unit and a population range, and leaves it to fill in the rest from general knowledge. A functional report hands over the same result with its optimal range, which band it falls in, what the marker does, what a high or low result can mean, which body system it belongs to, how it has moved since last time, and which tests were not run.

That last item matters more than it sounds. A product that knows which tests were not in the panel is far less likely to tell a user something the data could never have supported, and unsupported confidence is the failure mode that gets health apps into trouble.

For a product that surfaces results to users, or one that passes them to a language model to summarise, this is the difference between a number your product has to interpret and a number that arrives already interpreted, with its reasoning and its limits attached. Ranked concerns give your interface something to lead with. System groupings stop a model inventing its own. And because the comparison against the previous test is already done, your product can talk about direction rather than a single snapshot from the day of the draw.

What this looks like commercially

The account model is the one our practice partners use: no fixed minimum, order through the month, settle monthly at a wholesale rate, and set the price your own users pay. Your users need no doctor's referral, which removes the step that usually breaks a digital sign-up. Collection runs through the three branches, plus nurse call-outs and home kits. Blood results come back in 2 to 5 working days and the functional report in 7 to 10.

On integration, plainly

Reports are delivered as documents today. There is no public API. If your product needs results in a structured form it can read, tell us which markers and what format, and we will tell you what we can do, on what timeline, and what would need building. We would rather scope that with you than promise an integration that does not exist.

Getting a functional blood test in South Africa

Epicentre is a walk-in lab. You book your own blood test, with no doctor's referral, at branches in Cape Town, Johannesburg and Durban. Blood results come back in 2 to 5 working days by encrypted email, and the ODx functional report follows in 7 to 10 working days.

Most blood testing in South Africa still goes through a referral. You see a doctor, the doctor decides what to test, and the results go back to the doctor. That works well when you already have a reason to be there. It works less well when you just feel flat and have nothing particular to report, which is exactly where a watch tends to leave people. Walking in skips that step, and you pay one price you can see up front instead of a consultation plus a lab account.

Worth being precise about the referral, because it is widely misunderstood: a referral is about payment, not access. If you are paying cash you need no referral for any test. If you intend to claim from a medical scheme, you almost always do need one, with the right ICD-10 code from your doctor, or the claim is rejected and you pay cash anyway.

Cost is the real catch, and a wide panel is not a small purchase. Three things soften it. The functional report is included with any qualifying blood panel, small ones as well as large, so starting modest is perfectly sensible. Payflex splits anything over R1,200 into four interest-free instalments over six weeks. And there is 10% off for students with a Varsity Vibe ID and 10% for pensioners. Epicentre issues a tax invoice with its HPCSA practice number and test codes, so you can submit a scheme claim yourself if you have a referral. Visitors from abroad book on the same terms as everyone else.

All three branches are closed on weekends and public holidays. Results are emailed, encrypted, to the address you register with. One WhatsApp number covers all three: 072 843 7564.

Choosing a panel

Every panel below comes with the functional report. The difference is how many body systems it has enough results to score. All three need you to fast for 8 to 12 hours beforehand, water only, and the two larger panels include cortisol, so those need a morning appointment before 10am.

Not sure which fits? Compare the panels and see what each biomarker means. Prices are 2026 cash rates including VAT and may change without notice; in-store pricing applies.

Frequently asked questions

What these words mean

Estimate

A number calculated from surface signals rather than measured, such as a sleep stage worked out from movement and heart rate. Good for spotting change, one step removed from the thing itself.

Measurement

A number taken directly from a sample, such as how much of a hormone is present in your blood. Not calculated from anything else.

Standard range

The range your lab compares you against, worked out from lots of ordinary people. A result inside it is called normal.

Optimal range

A tighter range showing where a result usually sits in people who are well. Your result can be inside the standard range and outside this one.

Biomarker

Something in your blood that can be measured and that tells you how part of your body is working. It can show that something is off balance. On its own it cannot tell you why.

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