PURPOSE The temporal artery biopsy (TAB) has long been the standard for diagnosing temporal arteritis (TA), but in practice this test is less than 100% sensitive; false-negative biopsy results are known to occur. The true sensitivity of a single TAB cannot be directly observed, because there is no true gold standard for comparison. The authors propose a mathematical method for calculating the true sensitivity of the TAB, using data from published bilateral TAB RESULTS:
METHODS Based on Bayesian methodology, this statistical technique can be used to calculate the true sensitivity of a single TAB with data from studies reporting the results of bilateral simultaneous TABs. This technique also allows for calculation of the true prevalence of TA in a study population. Bootstrap techniques are used to provide confidence intervals. This technique is applied to data derived from four studies in the literature. results. With this methodology, the sensitivity of a single TAB is calculated to be 87.1% (95% confidence interval, 81.8%-91.7%).
CONCLUSIONS Knowledge of the true sensitivity of any imperfect test is necessary for an accurate decision analysis, because it can affect the optimal diagnostic-therapeutic pathway. Although few studies report results of bilateral simultaneous TABs, such data are important because they permit the calculation of the true TAB sensitivity. The authors believe that this mathematical method is superior to observational methods (e.g., clinical criteria) for estimating the true sensitivity of a TAB.