Understanding the direction of bias in studies of diagnostic test accuracy.
Ordering and interpreting diagnostic tests is a critical part of emergency medicine (EM). In evaluating a study of diagnostic test accuracy, emergency physicians (EPs) need to recognize whether the study uses case-control or cross-sectional sampling and account for common biases. The authors group biases in studies of test accuracy into five categories: incorporation bias, partial verification bias, differential verification bias, imperfect gold standard bias, and spectrum bias. Other named biases are either equivalent to these biases or subtypes within these broader categories. The authors go beyond identifying a bias and predict the direction of its effect on sensitivity and specificity, providing numerical examples from published test accuracy studies. Understanding the direction of a bias may permit useful inferences from even a flawed study of test accuracy.
Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, CA; The Emergency Department, Mills-Peninsula Medical Center, Burlingame, CA.
Michael A
MA
Kohn
Christopher R
CR
Carpenter
Thomas B
TB
Newman
D003430:Cross-Sectional Studies; D003955:Diagnostic Tests, Routine; D004635:Emergency Medicine; D006801:Humans; D012107:Research Design; D015983:Selection Bias; D012680:Sensitivity and Specificity