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Studies of diagnostic test accuracy: Partial verification bias and test result-based sampling.
1Epidemiology and Biostatistics, UCSF: University of California San Francisco, CA USA.
Journal of Clinical Epidemiology
|February 6, 2022
Summary
Partial verification bias in diagnostic test accuracy studies can be avoided by applying the reference standard to all positive index tests and a random sample of negative ones. This method requires adjusting for sampling fractions to accurately estimate test performance.
Area of Science:
- Medical Diagnostics
- Biostatistics
Background:
- Partial verification bias is a challenge in diagnostic test accuracy studies.
- It arises when a positive index test result influences the application of the reference standard.
Purpose of the Study:
- To describe alternative sampling frames for diagnostic test accuracy studies.
- To discuss and provide a method for avoiding partial verification bias.
Main Methods:
- The study proposes applying the reference standard to all individuals with a positive index test.
- A random sample of individuals with a negative index test should also receive the reference standard.
- This approach requires statistical adjustment for the sampling fraction in the test-negative group.
Main Results:
- This sampling strategy helps to mitigate partial verification bias.
- Estimating sensitivity and specificity necessitates accounting for the sampling fraction of the negative group.
Conclusions:
- Careful study design is crucial to avoid bias in diagnostic accuracy assessments.
- Understanding and addressing partial verification bias ensures more reliable evaluation of diagnostic tests.
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