Lead time bias

Lead Time Bias is a concept in epidemiology and medical testing that refers to the time between the early detection of a disease and the point at which the disease would have been diagnosed without early detection. This bias can lead to an overestimation of survival time and the effectiveness of treatment.

Definition

Lead time bias occurs when the time of diagnosis is brought forward by screening, but the time of death remains unchanged. This can give the illusion that survival time is longer, when in fact, the disease was just detected earlier. This bias is particularly relevant in the context of cancer screening programs, where early detection is often equated with improved survival rates.

Impact

The impact of lead time bias can be significant. It can lead to an overestimation of the benefits of screening and early detection, potentially leading to unnecessary treatments and interventions. It can also distort the understanding of disease progression and the effectiveness of treatments.

Prevention

To prevent lead time bias, it is important to use randomized controlled trials that compare outcomes in screened and unscreened populations. Additionally, using measures such as mortality rate rather than survival time can help to mitigate the effects of lead time bias.

See also

• Length time bias
• Overdiagnosis
• Screening (medicine)

This article is a medical stub. You can help WikiMD by expanding it!
Most recent articles Ongoing trials	Wikipedia