Which blood test should you choose? A practical guide

Don't start with the test, start with your question. What do you actually want to know? Once that's clear, the right blood test almost picks itself. Below we walk through the most common goals and symptoms, and match each one to the blood values and the test that fit.

That's the step most people skip. They search for a single value, when the real question is something else.

We're not neutral, because VitalCheck sells blood tests. Even so, we'll try to be honest below about what a test can and can't do for you.

Which blood test do I need? Start with your question, not the test

The shortest route to the right blood test runs through your goal. Do you want a general picture, to investigate a specific symptom, or to track a known risk? Each goal points to a different set of blood values. Do it the other way around, test first and reason later, and you tend to test too much or the wrong thing.

Ask yourself three questions. What do I notice in my body? What do I want to prevent or follow? And do I already know which value I'm after? Your answer decides whether you pick a broad check or a targeted test. A good starting point is our piece on what a preventive blood test does and doesn't show.

Decision aid: from symptom or goal to the right blood test

Find your goal or symptom in the table below. You'll see straight away which blood values matter, which test fits, and, just as important, what that test can't tell you. Use it as a starting point, not a diagnosis.

Below we walk through the most commonly chosen situations in a little more detail.

Do you want a general health check?

For a broad picture without a specific symptom, a general health check fits best. It measures your blood count, blood sugar, cholesterol, and your liver and kidney values in one go. It gives a snapshot of your baseline health, handy as a reference point to compare against later.

Want it broader? An extended check adds values like vitamins, iron and thyroid. Torn between narrow and broad? Start with the basic health check and expand later. If you'd rather measure more at once, choose the extended health check.

Which one suits your age? We covered that in which blood test by age.

Do you often feel tired or run down?

With ongoing fatigue, look first at your iron stores, thyroid and vitamins. Ferritin shows how much iron you have in reserve, TSH gauges your thyroid, and vitamin B12 and D belong in there as standard. Together they explain a large part of physical tiredness.

A targeted fatigue panel bundles these values. Worth knowing: blood doesn't tell you everything. Poor sleep, stress or an overfull life won't show up in a tube, and those are often the real causes.

Do you suspect a vitamin deficiency?

With a suspected deficiency, test in a targeted way, not everything at once. In the Netherlands, vitamin D and vitamin B12 are the most common shortfalls, especially if you're rarely outside or eat plant-based. Folate matters around a wish to conceive or pregnancy.

A broad vitamin panel sounds thorough, but most minerals and vitamin C usually aren't in it, and they say little in blood anyway. So start with vitamin D and B12. Which symptoms go with which deficiency, we list in recognising a vitamin deficiency.

Do you have thyroid symptoms?

For the thyroid you start with TSH, often alongside free T4. TSH is the control hormone and reacts quickly to an under- or overactive thyroid. If that value is off, free T4 gives more direction. Only after that do antibodies come into play.

A thyroid panel bundles these values into one test. Bear in mind that a single off TSH value doesn't pinpoint a cause yet. Sometimes a doctor repeats the measurement before drawing a conclusion.

Want to check hormones, cycle or fertility?

Which hormones you measure depends on your question and your sex. For women it's often oestradiol, FSH, LH and sometimes AMH, for men mainly testosterone. The right set differs per situation, and with a cycle the day you draw blood weighs heavily.

So choose a targeted hormone panel for women that matches your question. Test at the wrong point in your cycle and a normal value can still look out of range. For anyone approaching menopause, different values apply again.

Want to check cholesterol, heart or blood sugar?

For your heart and blood vessels, look at your cholesterol and blood sugar. A lipid panel measures total, LDL and HDL cholesterol plus triglycerides, and sometimes Lp(a) as a hereditary risk factor. For your sugar balance, fasting glucose and HbA1c count, the value that reflects your average blood sugar over weeks.

A lipid panel is a logical starting point around your forties or with cardiovascular disease in the family. It's still a blood test, not a heart or vascular scan. Which blood values shape your risk, you can read in preventing cardiovascular disease.

Do you need an STI test?

An STI test is a separate track. Which pathogens you test for depends on your situation, and timing is precise: soon after possible contact, a test can still be false-negative because of the window period. VitalCheck focuses on preventive testing, not STI care.

For an STI test, go to the GGD or a provider that specialises in it. That's not a detour, but the place where you get the right guidance and retest advice.

How do you avoid testing too much or too little?

More measuring isn't automatically better. Test without a reason and there's a bigger chance a value lands just out of range by chance, while nothing is wrong with you. That leads to needless worry and sometimes to follow-up you didn't need.

Thuisarts.nl, the public information from Dutch GPs, puts it plainly. A result can be good while you do have something, or bad while nothing is wrong, leaving you worried for no reason (Thuisarts.nl). So test with a question in mind, not just the broadest panel you come across.

The RIVM points to something similar with standalone self-tests. In 2022 there were at least 161 different self-tests on sale, and for many of them there's little data on how reliable they are (RIVM, 2023). A result is only as useful as the test and the explanation around it.

With or without a GP: where to have the test done?

If you have a medical symptom, your GP is the right starting point, and blood drawn on referral is covered by basic insurance. If you want to test preventively without a symptom, you can do that with a private provider, without a referral and at your own expense. The full explanation of that route is in our complete guide to blood tests without a referral. It also covers which providers exist, how to arrange it and, because the draw matters, whether you're better off testing at home or at a collection point.

A result without an explanation is only half the story

Choosing the test is step one. Just as important is what you do with the result. A row of numbers with the odd arrow says little on its own, and can cause needless alarm or let something important slip by.

That's why at VitalCheck a BIG-registered doctor reviews every result. You don't get raw lab numbers, but a report in plain language about what the values may mean in your case. That report is meant as insight, not a diagnosis. For treatment decisions, your GP remains the right person to turn to.

Already know exactly which marker you want? With the custom test builder you put together your own test from more than 250 biomarkers. That way you test precisely what you want to know, without a broad panel you only half need.

Frequently asked questions

Which blood test should I choose if I have no symptoms?

Without symptoms, a general health check fits best, as a reference point for later. If you have a specific goal, like tracking your heart or your vitamins, choose a targeted test. Better to start narrow and expand than the other way around.

How quickly do I get the result?

At VitalCheck you arrange it online without a referral, usually get a referral via ZorgDomein within a few hours, and the result with a doctor's report follows within a few business days. The exact timing depends on the type of test.

Do blood values differ by age and sex?

Yes. For many values, labs use separate reference ranges for men and women, and sometimes for age. A value that's normal for one person can sit just out of range for another. That's why an explanation with your result matters.

What does VitalCheck do with my data?

Your health data falls under privacy law and is treated confidentially. Your result is for you and the reviewing doctor. If you want the detail, read the privacy statement on the site.

Choose your test on your goal, not on a loose term you came across somewhere. Start with a basic health check if you like, see what comes out, and test more specifically where needed. One thing we're glad to take off your hands: you don't have to decode the result yourself.

Every blood test result at VitalCheck includes an assessment by a BIG-registered doctor. For treatment decisions, always discuss your results with your GP.

References

1. Thuisarts.nl (NHG). Ik wil misschien laten onderzoeken of ik wel gezond ben. Accessed 2026.
2. RIVM. Reliability of health tests. rivm.nl/gezondheidstesten/betrouwbaarheid.
3. RIVM. Growing and diverse supply of self-tests, but little data on use, impact and reliability. 2023.
4. Galior KD, Baumann NA. Challenges with At-home and Mail-in Direct-to-Consumer Testing. Clin Lab Med. 2020;40(1):25-36. PMID: 32008637.