Match each epidemiological research scenario with the specific type of bias or confounding it best describes.
- In a case-control study on congenital anomalies, mothers of affected infants are more accurate and thorough in reporting mild illnesses during pregnancy compared to mothers of healthy infants.Recall bias
- An observational study evaluating medical versus surgical therapy for heart failure finds higher mortality in the surgical group, primarily because physicians recommend surgery to patients with more advanced disease.Confounding by indication
- Subjects enrolled in a randomized trial for a new wearable fitness device significantly increase their daily step counts solely because they are aware that their activity is being monitored.Hawthorne effect
- A prospective cohort study tracking cognitive decline over a decade loses a disproportionate number of its most severely impaired participants to follow-up, resulting in an underestimation of the decline rate.Attrition bias
- A novel imaging technique detects asymptomatic tumors two years earlier than standard screening, falsely inflating the measured survival time from diagnosis without actually prolonging the patients' lives.Lead-time bias
Cevap
The congenital anomaly study demonstrates recall bias. The heart failure study demonstrates confounding by indication. The fitness trial demonstrates the Hawthorne effect. The cognitive decline study demonstrates attrition bias. The early tumor detection demonstrates lead-time bias.
Each specific scenario accurately matches its epidemiological definition. Differential memory of exposures identifies recall bias. When underlying severity dictates treatment allocation, confounding by indication occurs. Behavioral change due to being watched is the Hawthorne effect. Systematic and differential dropouts represent attrition bias. Lastly, prolonging the time between diagnosis and death without delaying the time of death is lead-time bias.
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Anahtar Kavram
Identifying various forms of research bias and confounding in clinical and epidemiological studies.