What Is a qFIT Test? GP Guide to Bowel Cancer Screening

Bowel cancer is the UK's 4th most common cancer and the 2nd biggest cancer killer, claiming around 17,700 lives every year. The frustrating part is that when bowel cancer is caught early, it's one of the most treatable cancers there is.

Diagnosed at Stage 1, over 90% of people survive five years or more. By Stage 4, that figure drops to around 10%. The difference between those two outcomes often comes down to one thing: whether or not the cancer was picked up before symptoms became obvious.

Brooksby Medical Bowel Cancer Screening test (qFIT)

That's where the qFIT test comes in. It's the same type of test used by the NHS Bowel Cancer Screening Programme, and it's now available privately through Brooksby Medical for £59, with results reviewed and reported by a doctor within 2–3 working days.

So what exactly is a qFIT test?

qFIT stands for quantitative Faecal Immunochemical Test. In plain English, it's a stool test that looks for tiny traces of blood in your poo, amounts so small you'd never notice them yourself. This is called occult (hidden) blood, and it can be an early warning sign of bowel cancer, polyps, or other conditions affecting your gut.

The "quantitative" part is important. Unlike older tests that just gave a yes-or-no answer, qFIT actually measures exactly how much blood is present, reported in micrograms per gram of stool (µg/g). This gives your doctor a much more useful picture: a higher number means a higher likelihood that something needs investigating.

How does the test actually work?

The science behind qFIT is clever but the process for you is very straightforward.

Inside the laboratory, the test uses antibodies that specifically recognise human blood. These antibodies lock onto a protein called haemoglobin, the oxygen-carrying molecule in your red blood cells. If human blood is present in your sample, even in microscopic quantities, the antibodies bind to it and the reaction is measured.

This is a major improvement over the old guaiac test (gFOBt), which the NHS used for years before switching to FIT. The guaiac test reacted to any source of blood, including blood from red meat you'd eaten or certain raw vegetables. That meant you had to follow a special diet before testing, and it produced a lot of misleading results.

With qFIT, there are no dietary restrictions whatsoever. It only reacts to human blood, and because proteins from the upper gut get broken down during digestion, it's particularly good at detecting bleeding from the lower bowel, which is exactly where most bowel cancers develop.

What's it like to take the test?

Let's be honest: nobody's thrilled about the idea of a stool sample. But the qFIT collection is genuinely quick and straightforward. It takes less than a minute and you do it in the privacy of your own bathroom.

When you order your Brooksby Medical bowel cancer screening kit, you'll receive a small collection tube with a tiny probe attached to the cap. You simply:

• Collect a sample by scraping the probe across the surface of your stool (you don't need much at all)

• Push the probe back into the tube, which contains a buffer solution that preserves the sample

• Pop it in the post using the pre-paid, tracked Royal Mail return label we provide

That's it. No special diet beforehand. No fasting. No multiple samples over several days (the old test needed three). Just one quick sample and you're done.

💡 Top tip: Try to return your sample within a day or two of collecting it. Haemoglobin can degrade in warm temperatures, so don't leave it sitting around, especially in summer.

Why should you care about bowel cancer screening?

The statistics tell a stark story about why catching bowel cancer early matters so much. Diagnosed at Stage 1, over 9 in 10 people survive. By Stage 4, only 1 in 10 do. Yet more than half of bowel cancers in the UK are still diagnosed at Stage 3 or 4, when treatment is harder and outcomes are worse.

Cancers found through screening have a one-year survival rate of 97%, compared to just 49% for those diagnosed as emergencies. Early detection through screening is associated with significantly better survival outcomes.

What does the NHS offer?

The NHS Bowel Cancer Screening Programme now uses the FIT test and invites everyone aged 50 to 74 in England to complete a test every two years (the age range was recently expanded down from 60). Scotland and Wales also screen from age 50. You'll receive a kit in the post automatically when you're eligible.

In January 2026, NHS England also announced a welcome change: the screening threshold is being lowered from 120 to 80 µg/g, which is expected to catch around 600 additional cancers per year. This brings England in line with Scotland and Wales.

The NHS programme is excellent and you should absolutely complete your screening kit if you receive one. But there are some significant gaps:

• Under 50? You won't be invited, despite bowel cancer diagnoses in younger adults rising by 22% since the early 1990s

• Over 74? You're no longer automatically invited (though you can request a kit by calling the screening helpline)

• Between rounds? There's a two-year gap between NHS screening invitations during which cancers can develop

Who should consider a private qFIT test?

A private qFIT test can be a sensible step for anyone who wants a proactive snapshot of their bowel health. You might particularly want to consider it if:

• You're under 50 and not yet eligible for NHS screening

• You have a family history of bowel cancer or polyps, especially if a close relative was diagnosed before 50

• You're between NHS screening rounds and want peace of mind

• You're over 74 and haven't been invited recently

• You have mild or intermittent bowel symptoms you want to get checked

⚠️ Important: If you have significant symptoms (persistent change in bowel habit, blood in your stool that you can see, unexplained weight loss, or abdominal pain) don't wait for a screening test. See your GP. These symptoms warrant proper clinical assessment, and your GP may arrange an NHS FIT test as part of that investigation.

What does a negative result actually mean?

This is one of the most important questions people ask, and the research gives a very clear answer. A negative qFIT result (meaning your sample comes back below 10 µg/g) is extremely reassuring.

The NICE FIT study, a gold-standard, double-blinded study of nearly 10,000 symptomatic patients across 50 English hospitals, found that the negative predictive value of FIT at the 10 µg/g threshold was 99.6%. That means a negative qFIT reduces your likelihood of having bowel cancer to less than 1 in 200.

Other large studies have found even more reassuring numbers. A primary care evaluation in South West England reported a negative predictive value of 99.8%, and retrospective cohort studies in UK general practice have reported a cancer miss rate of just 7 cases per 10,000 negative tests.

For people under 50, the data is particularly striking. A large study of over 38,000 symptomatic patients aged 18 to 49 in South West England found FIT had a sensitivity of 92.4% and a negative predictive value of effectively 100% in this age group [Barlow et al., BJS, 2025].

📊 The key number: A negative qFIT has a negative predictive value of over 99%. In the largest UK studies, fewer than 1 in 200 people with a negative result turned out to have bowel cancer.

What if my result is positive?

A positive result means blood was detected above the threshold. Don't panic. This does not mean you have cancer. There are many common, non-serious causes of blood in stool: haemorrhoids, small tears in the lining (anal fissures), and inflammation from conditions like diverticular disease.

However, a positive qFIT result does need to be followed up. Your doctor-written Brooksby Medical report will explain your result in plain English and give you clear guidance on the next steps, which will usually mean speaking to your GP about a referral for a colonoscopy to look directly at the lining of your bowel.

In NHS data, only about 4–5% of people with a positive screening FIT are found to have cancer. Many others are found to have polyps (which can be removed before they ever become cancerous) or other benign conditions.

What the qFIT test can't do

It's important to be upfront about what qFIT can and can't do. Being realistic about its limitations is part of making an informed choice:

• It's a snapshot, not surveillance. The test only detects blood present at the moment you take the sample. Cancers don't bleed constantly; they bleed intermittently. A single negative test is reassuring but not a guarantee.

• It doesn't detect polyps well. Most polyps don't bleed enough to trigger a positive result. qFIT is primarily a cancer detection tool, not a polyp detection tool.

• It's not a diagnosis. qFIT is a triage test. A positive result tells you something needs investigating further; it doesn't tell you what's causing the bleeding.

• It doesn't replace clinical judgement. If you have concerning symptoms, a negative qFIT does not mean everything is fine. Always discuss ongoing symptoms with your GP regardless of your result.

When to See Your GP

A qFIT test is a screening tool for people without significant symptoms. If you have any of the following, see your GP directly rather than waiting for a screening result:

• A persistent change in bowel habit lasting more than three weeks

• Blood in your stool that you can see (not just detected by a test)

• Unexplained weight loss

• Persistent abdominal pain or bloating

• Unexplained iron deficiency anaemia

Your GP can arrange an NHS FIT test as part of the diagnostic pathway, and may refer you directly for colonoscopy under the two-week wait pathway if your symptoms warrant it [NICE NG12]. A negative qFIT result in someone with persistent symptoms does not rule out cancer. Always discuss ongoing symptoms with your GP regardless of your result.

How to get a qFIT test from Brooksby Medical

At Brooksby Medical, we've made the process as simple as possible:

• £59 for a home test kit, delivered free to your door with everything you need, including a pre-paid tracked return label

• Results within 2–3 working days, analysed by a UKAS-accredited laboratory

• Doctor-written report, every result is personally reviewed by a GP with clear, plain-English explanations and actionable next steps

• CQC registered, Brooksby Medical is regulated by the Care Quality Commission

Unlike many private providers that give you a raw number and leave you to Google what it means, every Brooksby Medical result comes with a doctor-written report. That means you get a proper medical interpretation of your result, written in language you can understand, with clear advice on what (if anything) to do next.

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The bottom line

Bowel cancer is common, it's serious, and it's rising in younger adults. But it's also one of the most preventable and treatable cancers when caught early. The qFIT test isn't perfect (no screening test is), but the evidence overwhelmingly shows that early detection finds cancers at a stage when treatment works best.

If you're eligible for NHS screening, use your kit when it arrives. If you're not yet eligible, or you want the reassurance of a test between screening rounds, a private qFIT test is a straightforward way to check.

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References

1. NICE. Quantitative faecal immunochemical testing to guide colorectal cancer pathway referral in primary care. DG56 (2023). NICE DG56

2. NICE. Suspected cancer: recognition and referral. NG12 (updated 2023). NICE NG12

3. Georgiou Delisle T, et al. Quantitative faecal immunochemical testing for symptoms of colorectal cancer: NICE FIT study. Journal of Clinical Oncology. 2020

4. Chapman C, et al. Early clinical outcomes of a rapid colorectal cancer diagnosis pathway using faecal immunochemical testing. British Journal of Cancer. 2021

5. Barlow GL, Bailey SE, et al. FIT performance in early-onset colorectal cancer in symptomatic patients aged 18 to 49. British Journal of Surgery. 2025

6. Cancer Research UK. Bowel cancer statistics. Cancer Research UK

7. NHS England. More sensitive bowel cancer screening threshold announcement. January 2026. NHS England

Written by Dr James Coleman, GP and founder of Brooksby Medical. Dr Coleman is a practising General Practitioner who founded Brooksby Medical to give patients direct access to the blood tests and clinical interpretation they need, without waiting lists.

Medically reviewed: March 2026 | Next review due: March 2027

Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Brooksby Medical is a screening service designed to supplement, not replace, NHS primary care. Blood test results should always be interpreted by a qualified healthcare professional in the context of your individual symptoms, medical history, and clinical picture. If you have concerns about your health, please consult your GP.