Common Biases: Test Interpretation Bias
- Test interpretation bias
Test interpretation, test review, or diagnostic bias results when observers of a study have prior knowledge
that influences their interpretation of the results. Sources of knowledge include remembering the outcomes of
accumulated cases or knowing the results of other tests.
This form of bias can occur in the clinical setting at the time of the clinical interpretation, when
the physician may have access to other test results or even pathology reports. Thus, a solution to eliminate test interpretation bias
is to have selected subjects interpret the study examination in a controlled setting and to blind participating observers from all clinical information.
Consider a study that is comparing the capability of CT and ultrasound for the detection of renal tumors.
When performing the ultrasound, neither the technician nor the interpreting radiologist should not be aware of the CT findings. The reasoning lies in
that the technician may have a tendency to analyze a location with more scrutiny if he or she is aware that the CT reader identified
a tumor in the same area. Therefore, the best way to avoid this type of bias is to withhold all clinical information from both the technician
and the radiologist.
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