What are the best health screening tests?
Our initial review suggests that many health screening tests come highly recommended (Table 1). However, some medical researchers have voiced concerns about a number of other screening tests, including the tests for breast and prostate cancer (Table 2). This doesn’t mean that you shouldn’t consider having these tests, but it does suggest that you consider the pros and cons. For instance, if you are at increased risk of an illness, then the case for screening is likely to be stronger, whereas if you are not at increased risk, the pros and cons may be more balanced. Discussing this with your doctor can help you decide if a particular type of screening is likely to help you.
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Highly recommended tests |
Tests with some concerns |
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i. FOBt (Faecal occult blood testing) ii. Sigmoidoscopy iii. Colonoscopy iv. Virtual colonoscopy |
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Descriptions of these tests are given in the two tables below.
Table 1 – Highly recommended tests
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Health screening test |
Description |
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AAA |
The NHS arranges AAA screening for UK men when they reach 65. This is a simple ultrasound scan of the abdomen. The aorta is the body’s main blood vessel, so it is important to check that it is in good working order. |
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BMI |
You just need your weight, your height and a BMI calculator to work out if you’re at risk of obesity, diabetes or heart disease, and whether you need to take medical advice. A BMI value of:
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Blood pressure |
Checking your blood pressure is important because there are usually no symptoms of high blood pressure, but if it isn’t treated, it can damage your heart, brain and kidneys. That’s why NHS Choices describes it as ‘the silent killer’ and recommends that all adults have their blood pressure checked at least every five years. You can have your blood pressure checked when you visit your doctor. Alternatively, the British Hypertension Society lists blood pressure monitors which have been clinically validated. These can be purchased from a range of sources, including online from organisations such as Amazon. A blood pressure value of:
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Cervical screening test |
Cervical cancer is mainly caused by two particular strains of HPV (human papillomavirus HPV 16 and HPV 18), a sexually transmitted disease. Because there are no symptoms, it is important for women to screen for these high-risk strains. In England, Scotland and Wales the older smear test has been replaced by HPV screening. Samples of cervical cells are tested for high-risk HPV first. This is a more effective test because it helps identify who is at higher risk of developing cell changes or cervical cancer. In the UK women are invited for cervical screening every three years between the ages of 25 and 49 and every five years from 50 to 64. Some US commentators suggest screening from an earlier age, every one or two years, depending on the number of sexual partners. Screening is particularly recommended for women who smoke, have many children, have used birth control pills for a long time, or have HIV. Using a condom significantly reduces the risk of HPV infection, although it does not completely eliminate the risk.
Vaccines Vaccines that protect against the four types of HPV that cause most cervical cancers have been offered to all 12- and 13-year-olds in school in England (both girls and boys) since September 2019. These vaccines are recommended, as they also help protect against some mouth and throat (head and neck) cancers and some cancers of the anal and genital areas. |
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Cholesterol |
As with high blood pressure, there are usually no symptoms of high cholestorol, but high cholesterol is believed to be associated with an increased risk of narrowing of the arteries, heart attack and stroke. Fortunately, the cholesterol test is very simple to administer (usually a simple pin prick) and will indicate your levels of ‘good’ cholesterol (HDL) and ‘bad’ cholesterol (LDL). The test is likely to be particularly worth taking if you have high blood pressure, diabetes, are overweight, have a high fat diet, have a family history of early cardiovascular disease, or have a close family member with a cholesterol-related condition. |
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Depression |
If you have been feeling particularly down for more than a few weeks, with little interest or pleasure in doing things, it may be worth seeing your doctor for a possible depression test. This test is an initial discussion with your doctor, who will ask you a number of questions to see if your symptoms suggest that you may have depression. |
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Diabetes |
A test for diabetes is another simple blood test and is particularly worthwhile if you have high cholesterol or high blood pressure. As diabetes can lead to a range of serious health complications early diagnosis is important. These complications include: damage to many parts of your body, including your eyes, heart, feet, nerves, and kidneys. Diabetes can also cause high blood pressure and hardening of the arteries. |
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Glaucoma |
Glaucoma results in optic nerve damage, caused by abnormally high pressure inside your eyes. It can potentially lead to blindness. Regular eye tests at the opticians can identify glaucoma. (Eye tests are free in the UK for the over 60s, as well as for those who have been diagnosed with diabetes, or are over 40 and have a close family member such as a parent, child, brother or sister who has glaucoma.) |
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HIV |
Having a test for HIV is advised if you have had unprotected sex with multiple partners, or with a partner who has HIV, is bisexual or who uses, or has used, injected drugs. |
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Kidney disease |
An annual blood test for kidney disease is recommended if you are in an ‘at risk’ group i.e., if you have diabetes, high blood pressure, coronary heart disease, stroke or a family history of kidney disease. |
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Sexually transmitted infections |
Tests for these infections are usually done through simple blood tests and are recommended if you are sexually active and have had unprotected sex with new partners. |
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Skin cancer |
It is advisable to see your doctor if you see any strange changes in the shape, size or colour of moles on your body – including moles which have an irregular shape, different colours or which bleed or ooze. |
Concerns about some screening tests
The value of some screening tests, however, has been the subject of debate.
In 2020 the prestigious scientific journal Nature reviewed the pros and cons of testing, in particular of testing for breast cancer and prostate cancer.
Three main concerns
- Overdiagnosis/false positives – when tests suggest that there’s a cancer but there is no cancer, this results in unnecessary and potentially harmful treatment.
- Some cancers are slow growing – this means that some people with these cancers are more likely to die with the disease rather than die from it.
- Treatment can sometimes have undesirable or harmful side effects, for example incontinence and erectile dysfunction in the case of the treatment for prostate cancer, and musculoskeletal symptoms, bone loss and osteoporosis, and heart problems in the case of breast cancer treatments.
These issues are more likely to arise where screening takes place on a population-wide level, as opposed to when an individual has been identified as being at risk.
Private health screening
Doctors in the UK have often expressed concerns about private health screening, claiming that this can be inaccurate and unreliable, for example giving false positives in some areas and missing significant symptoms in other areas.
They are also concerned that the technology and procedures used by private health organisations are not subject to the same quality criteria as in the NHS. A report in livescience.com takes the view that full body scans, as well home menopause and home Alzheimer’s tests, are usually of little value.
Table 2 – Test with some concerns
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Health screening test |
Description |
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Breast screening |
The independent review on breast screening chaired by Professor Michael Marmot in 2012 concluded that breast screening saves 1,300 lives in the UK each year. However, this benefit must be balanced against the harms of screening, especially the risk of overdiagnosis, leading to unnecessary treatment (such as surgery, hormone therapy, radiotherapy and chemotherapy, all of which can have significant side-effects). The review concluded overall that the benefits of breast screening outweigh the risks. To put the risk of overdiagnosis in context, Macmillan Cancer Support reports that current research suggests about 1 in 5 cancers (20%) diagnosed through screening would never have caused a problem. Breast screening, which starts routinely at the age of 50 in the UK, is likely to be particularly worthwhile as you get older, and if:
Regular breast self-examination is also recommended. If you find a lump in your breast, if the size or shape of your breasts change, or if there is discharge from a nipple, see your doctor for a check-up. |
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PSA blood test for Prostate cancer |
Some doctors consider that PSA tests help to detect possible prostate cancers, therefore enabling treatment to take place. Others note that up to 80% of men with a raised PSA don’t have prostate cancer. In addition, prostate cancer isn’t necessarily deadly (nearly 20% of men will be diagnosed with it but only 3% will die from it), and side effects of treatment can include incontinence and impotence. This may explain why some medical organisations now don’t recommend routine PSA screening. A Cochrane Library review of published randomised control trials (the ‘gold standard’ in medical research) concluded that: Pooled data currently demonstrates no significant reduction in prostate cancer‐specific and overall mortality. Harms associated with PSA‐based screening and subsequent diagnostic evaluations are frequent, and moderate in severity…. Men should be informed of this and the demonstrated adverse effects when they are deciding whether or not to undertake screening for prostate cancer. This report suggests the value of talking through the pros and cons of PSA testing with your doctor, in the light of your own particular circumstances. Symptoms of prostate cancer can include problems passing urine, pain with ejaculation and low back pain. |
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DEXA bone density testing for osteoporosis |
This test is seen as helpful by many doctors, as osteoporosis is a silent disease whose symptoms are usually not evident until it is too late. However, livescience.com points out that measurements can vary from scan to scan of the same person, as well as from machine to machine, and that higher bone mineral density identified in the screening may not mean stronger bones. Eating a diet rich in calcium and vitamin D, taking plenty of exercise and not smoking can all reduce the risk of osteoporosis. |
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Screening for bowel cancer/colon cancer |
This kind of screening has been generally recommended by the medical profession, because if bowel/colon cancer is caught early it is often curable, and a colonoscopy (unlike most other forms of screening) is a surgical intervention which not only detects cancerous and pre-cancerous polyps but can remove them at the same time. In Austria, for instance, men and women aged 50 and over are routinely invited to be screened for bowel cancer using colonoscopy. However, there are some caveats (see below). The four main types of screening tests for bowel cancer/colon cancer are listed below. |
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FOBt (faecal occult blood test) |
This test identifies tiny amounts of blood from pre-cancerous polyps or bowel/colon cancer in a small stool sample. This is a potentially helpful test but, like the PSA test for prostate cancer described earlier, the test may often suggest you are at risk when you’re not. A colonoscopy is then required to clarify the position. |
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Sigmoidoscopy
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This is a mini colonoscopy which explores the lower third of the colon. The disadvantage is that this test can sometimes be uncomfortable or painful, and very occasionally it can cause perforation and bleeding. It is worth trying to ensure that the doctor is experienced with this procedure. |
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Colonoscopy |
The NHS describes a colonoscopy as, ‘an investigation that involves looking directly at the lining of the large bowel. A sedative is given and then a thin, flexible tube with a tiny camera attached (a colonoscope) is passed into the back passage and guided around the bowel. If polyps are found, most can be removed painlessly with a wire loop passed down the colonoscope tube. These tissue samples are then checked for any abnormal cells that might be cancerous.’ It goes on to advise, ‘About five in ten people who have a colonoscopy will have a normal result; about four in ten will be found to have a polyp, which if removed may prevent cancer developing. About one in ten people will be found to have cancer when they have a colonoscopy.’ Most colonoscopies are safe. However, Healthline reports that complications, sometimes serious, can occasionally occur. This distinguishes colonoscopy from other, less invasive, cancer screening tests. The risk of complications during and after the test also seem to increase with age. sciencebasedmedicine.com comments that, ‘It is not yet known for certain whether colonoscopy can help reduce the number of deaths from colorectal cancer.’ This may be because some studies suggest progression to cancer is not a steady process and there may sometimes be regression, and because the main effect appears to be on left sided rather than right sided colon cancer. |
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Virtual colonoscopy
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During a virtual colonoscopy, gas is used to inflate the bowel via a thin flexible tube placed in the patient’s back passage. CT scans are then performed with the patient first lying on their back and then on their front. In this way, doctors can look at the images for polyps and signs of cancer. This is less invasive than a conventional colonoscopy and reduces potential complications. It is reasonably accurate at identifying large polyps, it doesn’t require sedation or an analgesic and is quicker to perform. However, like a colonoscopy, it still requires a laxative and bowel cleansing beforehand. Some disadvantages of virtual colonoscopy are that the patient is exposed to a dose of radiation (greater than four dental X-rays but below the level currently considered a significant health risk by the Health Physics Society). Also, the test isn’t reliable for detecting small polyps (i.e., less than 6mm), and if it detects polyps larger than 6mm a colonoscopy would be recommended anyway. A virtual colonoscopy finds it difficult to detect flat, depressed or indented lesions (which are more likely to be cancerous), |
Conclusion
Given the many benefits of screening tests acknowledged by the medical profession, as well as the questions raised by researchers into the potential complications, there is value in talking to your doctor about your own particular circumstances. This is particularly the case if you are experiencing new symptoms such as a lump in your breast or blood in your stool, or if you have a family history of a particular illness.
Reviewed and updated November 2021. Next review date October 2025.
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Other relevant articles on the Age Watch website:
- Illnesses: Cancer prevention guidelines
- Ageing: Look after your body
- Living longer: How can we stay healthy longer?