Guidance

NHS and commercial health screening tests: important considerations

Published 21 November 2023

The offer of health screening can be confusing and commercial health screening tests can be expensive. This publication explains important differences between NHS screening programmes and commercial health screening tests.

This can help people who are considering an offer of screening as well as health professionals who are asked for advice from someone who has been offered screening.

The NHS offers screening tests and programmes throughout a person’s lifetime, from pregnancy and birth right through to retirement.

Commercial companies also offer private health screening tests. These are sometimes called ‘health MOTs’, ‘health checks’ or ‘preventative tests’.

Sometimes these are tests which the NHS already offers, and the commercial organisation is offering more convenience. Sometimes they are tests the NHS does not currently recommend.

1. Screening principles

Good quality, evidence-based screening programmes do save lives and improve health outcomes. They do this by finding people who have a higher chance of developing a defined condition and offering them information, further tests and timely effective treatment.

However, all screening can do harm as well as provide benefits. Good screening does more good than harm.

Screening tests are not 100% accurate and do not provide a diagnosis.

Screening is not for people who have symptoms. People who have symptoms should always consult their GP.

2. Screening evidence and the UK National Screening Committee

The UK National Screening Committee (UK NSC) is the independent scientific committee that advises the NHS and government about all aspects of screening.

The UK NSC only recommends a screening programme if it is confident that high quality, peer-reviewed published evidence shows that its benefits would outweigh any harms. It assesses the evidence for screening against internationally recognised criteria.

The NHS delivers screening that is recommended by the UK NSC. The NHS delivers screening as a full programme that is accessible to everyone across the country, with built-in quality assurance to ensure all necessary steps take place.

A screening test alone is of no benefit unless appropriate support, advice and, if appropriate, intervention and follow-up, take place as part of a seamless process.

3. Potential harms of all screening (NHS and commercial)

Many people, including healthcare professionals, overestimate the benefits of screening and underestimate both the harms and the difficulty of delivering screening effectively.

The harms and limitations of all screening include:

1. Even the best screening test will not be 100% accurate. Tests may not always give clear-cut or reliable answers. They can lead to false reassurance, false alarms, and the discovery of uncertain findings.

2. False positive results are inevitable in screening. This is when a screening test shows up a potential condition, but further tests reveal there is not a problem. This leads to unnecessary worry, and follow-up tests and investigations which may carry risks of complications.

3. False negative results are also inevitable in screening. This is where a condition exists or is soon to arise, but the test result is normal. This means people are falsely reassured and may ignore signs or symptoms later, thinking everything must be fine. This can lead to delays in diagnosis and treatment.

4. Screening can lead to overdiagnosis and overtreatment. This is where screening uncovers conditions which would not have led to a problem in a person’s lifetime but which, once found, require treatment. This means people are treated unnecessarily, and sometimes suffer complications from medications, or from surgery.

5. The chance of harms rises if the screening test and programme is not delivered to high quality standards to everyone. Quality assurance is critical.

4. NHS screening programmes

The NHS has implemented 11 national screening programmes covering more than 30 different conditions. The UK NSC made positive recommendations for all these programmes.

The 11 national NHS screening programmes offer a complete end-to-end service, not just a test.

They provide information and support at every stage of the screening pathway, from the offer of screening through to potential follow-up tests and treatment for those people identified with a condition.

NHS screening programmes give people clear, concise, balanced information about the potential benefits, harms and limitations of the screening they are offered. This helps people to make an informed choice about whether to take up the offer of screening and to make choices at every stage of the screening pathway.

5. Commercial screening tests

A variety of organisations offer private health screening tests and/or health checks.

Some of these tests are also recommended by the UK NSC and delivered by the NHS, and some are not.

Commercially offered screening ranges from simple blood tests and physical examinations to full body scans and screening for serious conditions like aneurysms or heart failure. These tests may be endorsed by celebrities and journalists, who may receive financial rewards for making those endorsements.

Drawbacks of commercially motivated screening include:

1. Often they only offer a test. If an individual then receives an abnormal finding from the test, it is up to them to seek any advice, possible further investigation or treatment. Often the tests will need to be repeated by the NHS.

2. Companies may offer screening that is not evidence-based. This means there are no reliable studies confirming that it leads to improved health outcomes for those screened. Companies often promote screening as simply offering peace of mind.

3. Often there is no quality assurance, meaning the tests might not be the same everywhere.

5.1 Important questions to consider if offered private screening

What would be the benefits of having the test?

Is there any evidence that the test can lead to avoidance of an important health problem some time in the future? If the test only claims to offer peace of mind, then a fitness check and good advice about nutrition and physical activity might be a better option.

Is the test already offered for free on the NHS?

Some companies offer screening for conditions already covered by a free NHS programme. If so, the private test should be compared with the whole end-to-end quality assured NHS screening service, not just the test itself.

Is the company properly regulated?

It is a legal requirement that all providers of screening services in England are registered with the Care Quality Commission.

What do the fees cover?

Are the fees clear? Is there a pressurising ‘book now for a reduced price’ offer? Will the company charge extra to follow up results? If so, how much extra will it charge?

Can the test do more harm than good?

Some tests carry a risk in themselves. Has the company provided balanced information about what the test involves and any potential harms? Are the potential benefits properly explained? It is an ethical requirement for healthcare providers to give full information to inform an individual’s choice. Screening providers should offer the chance for individuals to discuss the balance of benefits and harms with a health professional.

What if the test picks something up?

If screening picks up a problem, is there a treatment available that is effective and acceptable? If the answer is ‘no’, would you want to have the test at all?

What if there are no clear results?

Is there a chance that the test will produce no clear result(s)? If so, what support will the company provide, will more tests be needed, what will they involve, how much will they cost and who will deliver them?

6. More information and advice

• NHS screening programmes

• Population screening explained

• Talk to your GP