Match each clinical research scenario with the specific type of bias or methodological flaw it best represents.
- An association is found between alcohol consumption and oral cancer, but the researchers fail to account for the fact that many alcohol consumers also smoke tobacco.Confounding
- A case-control study uses hospitalized patients as controls, which distorts the true association due to differing hospital admission rates.Berkson bias
- Patients enrolled in a diet and exercise trial increase their physical activity levels solely because they know they are being monitored.Hawthorne effect
- A new cancer screening test detects a higher proportion of slowly progressive, indolent tumors, making it falsely appear that the screening improves survival.Length-time bias
Cevap
Alcohol/Smoking is Confounding; Hospitalized controls is Berkson bias; Behavior change due to observation is the Hawthorne effect; Slow-growing tumor detection is Length-time bias.
Each scenario precisely maps to a foundational epidemiological concept: failure to account for an external associated variable represents confounding; selecting unrepresentative hospital-based controls represents Berkson bias; modifying behavior due to the presence of observers represents the Hawthorne effect; and selectively screening for slowly progressive diseases represents length-time bias.
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Anahtar Kavram
Identifying specific types of bias and confounding in clinical research.