BACKGROUND The purpose of this research is to discover whether measurement of cervical length and cervical volume at term is helpful in predicting the onset of labor in VBAC candidates. METHODS Transvaginal sonographic evaluations of the cervixes of pregnant women who desired to undergo VBAC were performed between 36 - 40 weeks gestation. Clinical information such as labor onset time, gestati...

Sensitivity and specificity are two components that measure the inherent validity of a diagnostic test for dichotomous outcomes against a gold standard. Receiver operating characteristic (ROC) curve is the plot that depicts the trade-off between the sensitivity and (1-specificity) across a series of cut-off points when the diagnostic test is continuous or on ordinal scale (minimum 5 categories)...

A Receiver Operating Characteristic (ROC) curve reflects the performance of a system which decides between two competing actions in a test of statistical hypothesis. This paper addresses the inference on ROC curves for the following problem: how can one statistically validate the performance of a system with a claimed ROC curve, ROC0 say? Our proposed solution consists of two main components: F...

Assessing the discriminative power of rating systems is an important question to banks and to regulators. In this article we analyze the Cumulative Accuracy Profile (CAP) and the Receiver Operating Characteristic (ROC) which are both commonly used in practice. We give a test-theoretic interpretation for the concavity of the CAP and the ROC curve and demonstrate how this observation can be used ...

Multiple diagnostic tools are used by emergency physicians, every day. In addition, new tools are evaluated to obtain more accurate methods and reduce time or cost of conventional ones. In the previous parts of this educational series, we described diagnostic performance characteristics of diagnostic tests including sensitivity, specificity, positive and negative predictive values, and likeliho...

We evaluated the feasibility of resazurin microtiter assay (REMA) for detecting cycloserine resistance of Mycobacterium tuberculosis. The cutoff value of the critical concentration of cycloserine resistance in vitro about M. tuberculosis isolates was determined innovatively by drawing the receiver operating characteristic (ROC) curve for the first time. The spending time of REMA ranged from 6 t...