Sample size calculations in studies of test accuracy.
Methods for determining sample size for studies of the accuracy of diagnostic tests are reviewed. Several accuracy indices are considered, including sensitivity and specificity, the full and partial area under the receiver operating characteristic curve, the sensitivity at a fixed false positive rate, and the likelihood ratio. Sample size formulae are presented for studies evaluating a single test and studies comparing the accuracy of tests. Four real examples illustrate the concepts involved in sample size determination. Lastly, various study design issues are discussed, such as sampling methods, choices in format for the test results, and the issue of replicated readings.
Obuchowski
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Department of Biostatistics and Epidemiology, Cleveland Clinic Foundation, OH 44195-5196, USA. nobuchow@bio.ri.ccf.org
D019540:Area Under Curve; D018427:Breast Implants / Q000009:adverse effects; D001943:Breast Neoplasms / Q000175:diagnosis; D019937:Diagnostic Techniques and Procedures / Q000592:standards*; D005189:False Positive Reactions; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis; D016013:Likelihood Functions; D008279:Magnetic Resonance Imaging; D008327:Mammography; D012372:ROC Curve; D011859:Radiography; D015203:Reproducibility of Results; D018401:Sample Size; D014463:Ultrasonography