The annual check-up feels self-evidently sensible. Catch things early, prevent problems, stay on top of your health. In some healthcare systems it's routine and expected; in others it barely exists.
The evidence for the general annual physical — as distinct from specific targeted screening — is considerably weaker than its cultural status suggests, and this has been examined fairly thoroughly.
What the reviews found
Systematic reviews of general health checks in adults have been conducted, pooling data from a number of randomised trials involving large numbers of participants.
The broad conclusion has been consistent: general health checks did not reduce overall mortality, and did not reduce deaths from cardiovascular disease or cancer, compared with no check.
They did increase the number of diagnoses made and the number of people started on treatments. Which sounds like it ought to be good and, at the population level, apparently wasn't enough to change outcomes.
This is a genuinely counterintuitive finding and it's worth sitting with rather than dismissing.
Why more diagnosis doesn't always help
The mechanism most often proposed is overdiagnosis: identifying conditions that would never have caused symptoms or harm during a person's life.
Every diagnosis carries consequences — anxiety, further investigation, treatment with its own risks, insurance implications, and the experience of becoming a patient. If the condition was never going to cause a problem, all of those consequences are pure cost.
There's also the false positive cascade. A borderline result on a test performed without a specific indication leads to further tests, some invasive, some carrying real risk, frequently concluding that nothing was wrong.
The base rate matters enormously here. Testing a person with symptoms is a different proposition from testing a person without them, and the same test performs very differently in the two populations.
What does have good evidence
This is the important distinction, because the finding above absolutely does not mean preventive medicine doesn't work.
Specific screening programmes, targeted at defined populations at defined ages, have solid evidence behind them and are recommended by essentially every health authority. Cervical, bowel and breast cancer screening within specified parameters. Blood pressure measurement. Cholesterol assessment in appropriate groups. Diabetes screening in those at elevated risk. Abdominal aortic aneurysm screening in specific groups.
These work because they're targeted — the right test, in the right population, at the right interval, where the condition is common enough and the intervention effective enough for the maths to work.
The general annual physical is a different thing: an unfocused survey of a person without symptoms, frequently including tests with no clear indication.
The parts that probably do help
Even critics of the annual physical tend to acknowledge that some elements have value, and they're mostly not the tests.
The conversation. A structured discussion about smoking, alcohol, exercise, diet and mental health, with someone who knows your history. Behavioural counselling in these areas has reasonable evidence behind it.
Vaccination review. Straightforwardly beneficial and easy to let slip.
Continuity. Having a relationship with a clinician who knows your baseline makes future problems easier to interpret. That's hard to measure in a trial and is repeatedly cited by practitioners as the real value.
And for some people, the appointment is the mechanism by which they raise something they'd otherwise have ignored. That's not nothing.
The commercial variety
Worth flagging separately: privately marketed comprehensive health screening packages, often including extensive blood panels and sometimes whole-body imaging.
These are the most aggressive version of the approach the evidence questions, applied to people without symptoms, and the risk of incidental findings is substantial. Whole-body scans in particular reliably find things — small abnormalities of no significance — which then require investigation.
Several professional bodies have advised against non-indicated whole-body screening for exactly this reason.
What I'd take from this
Not that you should avoid your doctor. The opposite, in a sense.
Participate in the specific screening programmes you're eligible for. Those are where the evidence is, and uptake is frequently poor.
See a clinician when something is wrong, and be specific about what's changed. Symptom-driven consultation is where diagnostic testing performs well.
And if you have a routine review, treat the conversation as the substance rather than the tests. Come with questions about the things that actually determine long-term health — activity, sleep, alcohol, mood, weight — because those are where the modifiable risk sits, and they're the part of the appointment most likely to be squeezed out by the blood work.
The occupational health version
Worth flagging separately because many people encounter health checks through an employer rather than a doctor. Workplace screening programmes vary enormously in quality, and some are essentially the commercial packages described above delivered at scale.
The elements with a genuine evidence base — blood pressure measurement, discussion of smoking and alcohol, mental health support signposting — are cheap and worth having. Extensive panels of tests on asymptomatic working-age adults are the part where the evidence thins.
There is also a privacy dimension that gets little attention. Understanding what your employer receives, and in what form, is worth establishing before participating, and the answer is not always what people assume.