What each test is worth
The same question for each: per 1,000 people, how many deaths from the disease does the test prevent? Some numbers come from trials (people invited, or randomly assigned to the test), others from a model that assumes people always attend; each has its own time span, written beside it. For osteoporosis the number is hip fractures, not deaths. So the tests are not ranked on one scale.
Each small square is a person; there are 10,000.
High-risk types of HPV, which over years can turn cells of the cervix into cancer. A positive test leads to a check of the cells and, if needed, a colposcopy, where changes are found before they become cancer.
8 per 1,000
cervical cancer deaths avoided per 1,000 women with an HPV test every 5 years from 30 to 65, compared with none: from 8.34 to 0.29 (modelled estimate, US)
modelled estimate
What the evidence says
Grade A (2018): a smear every 3 years from 21 to 29; from 30 to 65, an HPV test every 5 years, or a smear every 3. A 2024 draft adding self-collected HPV tests is not yet final.
USPSTF, Cervical cancer: screening (2018)
High blood pressure, which causes no symptoms and raises the risk of heart attack and stroke.
no death count for the test
No trial compares people whose blood pressure was measured with people whose was not. The benefit comes from treatment, which clearly cuts heart attacks and strokes.
Viruses that damage the liver silently for decades, up to cirrhosis or cancer. Hepatitis C is now cured with tablets in 8–12 weeks.
no death count for the test
No death count has been measured for the test itself. The benefit comes from treatment: hepatitis C is cured in over 95% of people treated.
HIV infection, which treated in time means a near-normal lifespan.
no death count for the test
The benefit comes from starting treatment early; no death count has been measured for the test itself.
Breast screening (mammogram)
40–74, every 2 years
Breast cancer while it is small, before it can be felt.
4.3 per 1,000
breast cancer deaths prevented per 1,000 women invited from 50, over 20 years
estimated from 11 trials
12.9 cancers found that would never have caused harm (overdiagnosis)
Invisible traces of blood in stool, a sign of polyps and bowel cancer. A positive test leads to a colonoscopy, where polyps can be removed there and then.
24–28 per 1,000
bowel cancer deaths avoided per 1,000 people screened from 45 to 75, modelled estimate (US)
modelled estimate
What the evidence says
Grade A from 50 to 75, grade B from 45 to 49 (2021): a FIT every year, a colonoscopy every 10 years, or another approved test. From 76 to 85, selectively.
USPSTF, Colorectal cancer: screening (2021)
Cholesterol and 10-year heart and stroke risk
40–75, every 5 years
Your chance of a heart attack or stroke in the next 10 years, worked out from cholesterol, blood pressure, age and smoking.
no death count for the test
The benefit comes from treatment: in 18 trials of adults with no previous heart attack or stroke, statins meant about 3.5 fewer deaths per 1,000 people treated, over 6 months to 6 years.
Type 2 diabetes and prediabetes, which can go years without signs.
no death count for the test
Screening trials found no fewer deaths over 10 years. The test is worth it if something changes afterwards: diet, activity, treatment.
Osteoporosis: bones that break in an ordinary fall.
5 per 1,000
hip fractures prevented per 1,000 older women, over 4–5 years (three trials)
measured in trials
Lung scan (low-dose CT) for smokers
50–80, every year
Lung cancer at a stage when it can still be operated on.
3 per 1,000
lung cancer deaths prevented per 1,000 heavy smokers scanned yearly, over about 7 years, compared with chest X-ray (NLST)
measured in a trial
Nearly a quarter of scans come back positive at first; almost all turn out to be false alarms.
What the evidence says
Grade B (2021): a scan every year from 50 to 80 for people with at least 20 pack-years who smoke now or quit in the last 15 years.
USPSTF, Lung cancer: screening (2021)
A swelling of the main artery in the abdomen that causes no pain and no signs until it bursts.
4.6 per 1,000
aneurysm deaths prevented per 1,000 men invited to one scan, over 13 years (MASS trial)
measured in a trial
In December 1948 the surgeon Rudolph Nissen opened Albert Einstein's abdomen in Brooklyn and found a large aneurysm on the aorta. There was no way to replace it, so he wrapped it in cellophane to stiffen it. Einstein lived six more years. In April 1955 the aneurysm burst; he refused surgery and died on 18 April. Today the same swelling shows up on a scan that takes a few minutes.
PSA test for prostate cancer
55–69, every 2 years
Prostate cancer, including many small tumours that would never have caused harm.
2.2 per 1,000
prostate cancer deaths prevented per 1,000 men aged 55–69 invited to PSA testing, over 23 years (ERSPC)
measured in a trial
More than 45% of men tested at every round had at least one false positive over 10 years, and 20–50% of the cancers found would never have caused harm.
Melanoma and other skin cancers, through an examination of all your skin, scalp included.
no death count for the test
No trial has shown fewer melanoma deaths from checking the skin of people without symptoms; the checks do find many spots that lead to biopsies.
How to get it
See a doctor about any mole that changes.
Common questions
What preventive screenings are covered at no cost?
Tests the US Preventive Services Task Force grades A or B must be covered at no cost by most private plans: blood pressure, cholesterol and statin assessment from 40, diabetes testing from 35 if overweight, colorectal screening from 45, mammograms every 2 years from 40, cervical screening from 21, lung CT for heavy smokers from 50, an aortic scan for men 65–75 who ever smoked, bone density for women from 65, and hepatitis C and HIV once.
What screenings should I get at 40?
Women: Cervical screening, Breast screening (mammogram), Blood pressure, Cholesterol and 10-year heart and stroke risk, Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes. Men: Blood pressure, Cholesterol and 10-year heart and stroke risk, Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes.
What screenings do I need at 50?
Women: Cervical screening, Breast screening (mammogram), Bowel cancer screening (FIT kit), Blood pressure, Cholesterol and 10-year heart and stroke risk, Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes. Men: Bowel cancer screening (FIT kit), Blood pressure, Cholesterol and 10-year heart and stroke risk, Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes. Smokers with 20 pack-years add a yearly lung CT from 50.
What screenings do I need after 65?
Women: Cervical screening, Breast screening (mammogram), Bowel cancer screening (FIT kit), Blood pressure, Cholesterol and 10-year heart and stroke risk, Bone density scan (DEXA), Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes. Men: Bowel cancer screening (FIT kit), Blood pressure, Cholesterol and 10-year heart and stroke risk, Hepatitis B and C, one-time test, HIV, one-time test, Blood sugar test for diabetes. A PSA test is a decision to make with your doctor. Smokers with 20 pack-years add a yearly lung CT from 50.
Is a full-body scan or yearly 'complete' check-up worth it?
Usually not. A Cochrane review of 17 trials found general health checks made no difference to deaths, and the FDA knows of no evidence that whole-body scans in people without symptoms do more good than harm. What matters is the screening that fits your age, most of it covered at no cost.
Ready-made lists
The list at 25, woman · The list at 25, man · The list at 30, woman · The list at 30, man · The list at 40, woman · The list at 40, man · The list at 50, woman · The list at 50, man · The list at 60, woman · The list at 60, man · The list at 70, woman · The list at 70, man
How the list was made
The evidence column follows the US Preventive Services Task Force (USPSTF) recommendations and grades. Grade A or B means most non-grandfathered private plans must cover the test in-network at no cost to you; in June 2025 the Supreme Court upheld the way the Task Force is appointed, which keeps that rule in place. Medicare and Medicaid have their own rules.
Lives saved are absolute: deaths avoided per 1,000 people, not '42% fewer'. Some come from trials (people invited, followed for a fixed number of years), others from models that assume you take every test for life. They are labelled separately and not ranked.
This page does not replace your doctor. With symptoms, a family history of cancer or a long-term condition, your list is different and is made with them.