A study is funded by the tobacco industry to examine the association between smoking and lung cancer. They design a study with a prospective cohort of 1,000 smokers between the ages of 20-30. The length of the study is five years. After the study period ends, they conclude that there is no relationship between smoking and lung cancer. Which of the following study features is the most likely reason for the failure of the study to note an association between tobacco use and cancer?
ALate-look bias
BLatency period
CConfounding
DEffect modification
EPygmalion effect
A randomized controlled trial is conducted investigating the effects of different diagnostic imaging modalities on breast cancer mortality. 8,000 women are randomized to receive either conventional mammography or conventional mammography with breast MRI. The primary outcome is survival from the time of breast cancer diagnosis. The conventional mammography group has a median survival after diagnosis of 17.0 years. The MRI plus conventional mammography group has a median survival of 19.5 years. If this difference is statistically significant, which form of bias may be affecting the results?
ARecall bias
BSelection bias
CMisclassification bias
DBecause this study is a randomized controlled trial, it is free of bias
ELead-time bias
A 55-year-old man presents for physical and preventive health screening, specifically for prostate cancer. He has not been to the doctor in a long time. Past medical history is significant for hypertension that is well-managed. Current medication is hydrochlorothiazide. He has one uncle who died of prostate cancer. He drinks one or two alcoholic drinks on the weekends and does not smoke. Today his temperature is 37.0°C (98.6°F), blood pressure is 125/75 mm Hg, pulse is 82/min, respiratory rate is 15/min, and oxygen saturation is 99% on room air. There are no significant findings on physical examination. Which of the following would be the most appropriate recommendation for prostate cancer screening in this patient?
AContrast CT of the abdomen and pelvis
BSerum PSA level
CDigital rectal examination
DNo screening indicated at this time
ETransrectal ultrasound (TRUS)
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