For how we live.
US preventive guidance recommends against a resting or exercise ECG in symptom-free adults at low cardiovascular risk, and finds the evidence insufficient at higher risk. The tracing rarely changes treatment.
Commercial full-body scans promise early detection to people with no symptoms. The data show they find something to chase in nearly half, and cancer in about one in a hundred.
US guidelines recommend a one-time ultrasound for men aged 65 to 75 who ever smoked, and advise against it for most women. The split turns on who actually benefits from finding a silent bulge in the aorta.
For adults with no symptoms, the US Preventive Services Task Force recommends against carotid ultrasound screening — a rare 'D' grade, because finding the narrowing does more harm than good.
A Cochrane review of 251,891 participants found no effect on total, cancer or cardiovascular mortality, at high certainty for the first two. The finding is about check-ups, not about all screening.
Six randomised trials found no benefit from immediate imaging over usual care. A separate review explains the reason: most of what a scan finds is present in people with no pain at all.