Match each clinical research scenario with the specific type of epidemiological bias it best describes.
- A case-control study evaluating cholelithiasis and colorectal cancer selects both cases and controls exclusively from hospitalized patients, artificially inflating the exposure frequency.Berkson bias
- Subjects with newly diagnosed multiple sclerosis report their past minor viral infections with much greater detail and frequency than healthy neighborhood controls.Recall bias
- During a trial assessing a new protocol to reduce surgical site infections, surgeons' adherence to sterile techniques improves simply because they know they are being monitored.Hawthorne effect
- A novel screening imaging protocol detects pancreatic cancer earlier, making survival time from diagnosis appear longer even though the actual time of death remains unchanged.Lead-time bias
Answer
The scenarios correctly pair with Berkson bias (hospitalized cases/controls), Recall bias (differential memory of exposures), Hawthorne effect (behavior change due to observation), and Lead-time bias (artificial survival increase due to early detection).
Each scenario illustrates the hallmark characteristics of a specific bias. Selecting hospitalized patients introduces Berkson bias. Differential memory of past exposures is the definition of recall bias. Subjects altering behavior due to observation defines the Hawthorne effect. Finally, artificially prolonged survival times from early screening without mortality benefit represents lead-time bias.
Step-by-Step Solution
Key Concept
Identification and distinction of common epidemiological biases in study design and data collection.
Estimated Time:1m 30s