A hospital initiates annual low-dose CT screening for high-risk smokers (age 55-75, ≥30 pack-years). Five years later, screened patients (BP 138/82, HR 78, RR 16, SpO2 98%) demonstrate increased median survival post-diagnosis compared to unscreened controls, yet disease-specific mortality remains identical between groups. CT findings show early-stage nodules in screened cohort. Notably, no difference exists in overall mortality. Which phenomenon best explains the improved survival interval without mortality benefit?
- A)Lead-time biasGABARITO
- B)Length-time bias
- C)Recall bias
- D)Selection bias
- E)Confounding by indication
Explicação
Lead-time bias occurs when earlier detection makes survival from the time of diagnosis appear longer even though the natural course of disease and time of death are unchanged. The clue is unchanged disease-specific mortality despite apparently longer survival ... Ver explicação completa e trilha adaptativa →