A researcher is conducting a study to evaluate a new point-of-care test for detecting acute myocardial infarction in the Emergency Department. The test is initially validated in a tertiary cardiac centre using patients who have already been diagnosed with definite STEMI and healthy hospital staff as controls. The test shows excellent sensitivity (98%) and specificity (95%).
However, when implemented in various Emergency Departments, the test's performance is significantly lower.
Which of the following best explains this discrepancy?
A
Calibration error in the testing equipment
B
Spectrum bias in the validation cohort
C
Verification bias in the control group
D
Performance bias in the emergency setting
E
Detection bias in the follow-up phase