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Skyscape - USMLE® Question of the Week


A new screening test was devised to detect pancreatic cancer at early stages using a serum marker (CA 19-9) of the disease. A study of this new test showed that its use prolongs the survival of patients with pancreatic cancer by several months. The researchers concluded that use of the test improves the prognosis of patients with pancreatic cancer. Which of the following is a potential problem with this conclusion?

A Observer's bias
B Measurement bias
C Lead-time bias
D Confounding
E Ascertainment bias

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iOS & Android Apps

980+ total questions*
1000+ total questions*
450 Questions, Ans and Rationales
First Aid for the USMLE Step 1
Includes Netters Anatomy Atlas
Anatomy Flash Cards
* In app purchase required


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