ylidiagnostiikan

Ylidiagnostiikan, often rendered in English as overdiagnosis, is the diagnosis of a medical condition that would not have caused symptoms or harm during a person’s lifetime. It commonly arises in the context of screening programs and advances in diagnostic techniques, which detect abnormalities that may never become clinically relevant.

Overdiagnosis is distinct from a false positive. A true diagnosis can still be clinically irrelevant if the condition would not progress to cause problems; false positives are incorrect test results. Overdiagnosis can lead to overtreatment and exposure to harms without improving health outcomes, and it can distort perceptions of disease risk and the benefits of screening.

Causes include highly sensitive screening that detects indolent or slow-progressing diseases, broadened disease definitions, and incidental findings from imaging or laboratory testing. Biases such as lead-time and length bias can exaggerate apparent survival without reducing mortality.

Consequences include physical harm from unnecessary procedures, side effects from treatments, psychological stress, and increased healthcare costs. There may also be unnecessary anxiety, stigma, and misallocation of resources that could instead support higher-value care.

Mitigation strategies emphasize informed, shared decision-making; transparent communication about the potential benefits and harms of screening and testing; and guideline-based practices that discourage low-value testing, focusing on patient-centered care and targeted screening where benefits clearly outweigh harms.