Screening myths
| MYTH | REALITY |
|---|---|
| Earlier is better | While early detection is key for a successful screening test, we need more information. Evidence from trials should show the intervention improves health if the disease is found earlier and that resultant harms are acceptable |
| More is better | Detecting more disease is not a synonym of benefit. We need information on the balance between benefits and harms before proceeding. The most unbiased indicator of benefit is all-cause mortality, but this outcome is rarely achieved. False-positive results and overdiagnosis are important indicators of harm |
| Newer is better | Newer tests tend to be seen through a positive lens. They may detect more disease, but the use of these new methods should be subjected to clinical trials to demonstrate the magnitude of benefits and harms |
| Screening saves lives | This is the most enduring myth of all, but the reality is more nuanced. Patients should know the ultimate impact on their lives from screening based on mortality from all causes. Disease-specific mortality can result in a more favourable perception of benefit. Absolute estimates of benefit (and harm) should be transparently provided for meaningful shared decision making |