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Lowest Accuracy (lowest + accuracy)
Selected AbstractsEvaluation of endoscopic and imaging modalities in the diagnosis of structural disorders of the ileal pouchINFLAMMATORY BOWEL DISEASES, Issue 9 2010Linda Tang MD Abstract Background: Computerized tomography enterography (CTE), gastrograffin enema (GGE), magnetic resonance imaging (MRI), and pouch endoscopy (PES) have commonly been used to assess ileal pouch disorders. However, their diagnostic utility has not been systematically evaluated. The aims of this study were to compare these imaging techniques to each other and to optimize diagnosis of pouch disorders by using a combination of these diagnostic modalities. Methods: Clinical data of patients from the Pouchitis Clinic from 2003 to 2008 who had a PES and at least 1 additional imaging modalities (CTE, GGE, or MRI) used for evaluation of ileal pouch disorders were retrospectively evaluated. We analyzed the accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) with which these tests were able diagnose pouch inlet and distal small bowel and pouch outlet strictures, pouch fistulas, sinuses, and leaks. Subsequently, accuracy was recalculated by combining 2 imaging modalities to see if this could enhance accuracy. Results: A total of 66 patients underwent evaluation with PES and 1 other imaging modality as follows: PES + CTE (n = 23), PES + GGE (n = 34), and PES + MRI (n = 26). The mean age was 41.5 ± 14.5 years, with 28 being female (42.4%). Sixty patients (90.9%) had J pouches and 59 (89.4%) had a preoperative diagnosis of ulcerative colitis. Overall, CTE, GGE, MRI, and PES all had reasonable accuracy for the diagnosis of small bowel and inlet strictures (73.9%,95.4%), outlet strictures (87.9%,92.3%), fistula (76.9%,84.8%), sinus (68.0%,93.9%), and pouch leak (83,93.9%). CTE had the lowest accuracy for small bowel and inlet strictures (73.9%) and MRI had the lowest accuracy for pouch sinus (68.0%). Combining 2 imaging tests can increase the accuracy of diagnosis to 100% for strictures, fistulas, sinus, and pouch leaks. Conclusions: CTE, GGE, MRI, and PES offer complementary information on disorders of the pouch and the combination of these tests increases diagnostic accuracy for complex cases. (Inflamm Bowel Dis 2010) [source] Sensitivity and specificity of current diagnostic tests for gill-associated virus in Penaeus monodonJOURNAL OF FISH DISEASES, Issue 11 2006J Munro Abstract This study reports the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy between a reverse transcriptase-nested polymerase chain reaction (RT-nPCR) and an enzyme-linked immunosorbent assay (ELISA) for the detection of gill-associated virus (GAV) from a sample of 120 Penaeus monodon. Subsequently, the same comparisons were applied to the ELISA and haemagglutination (HA) assays for detection of GAV from a second 120 prawns. The optical density (OD) or dilution cut-off point had a direct influence on the tested parameters. The cut-off OD of 0.5,0.6 with the ELISA produced a sensitivity of 98% compared with RT-nPCR. However, these OD produced the lowest accuracy (85.8% and 86.7%, respectively). The OD cut off of 0.75 resulted in the highest accuracy (91.7%) and NPV (81.3%) while it had the second highest sensitivity (97%) and PPV (93.3%). However, the OD cut off of 0.9 had the highest specificity (80%). With regards to HA, the titre cut off at 8 resulted in the highest sensitivity, specificity and NPV (94%, 100% and 100%, respectively) compared with the ELISA, while the HA titre of 16 gave the highest accuracy (73%) and the second highest specificity (75%). A HA titre of 64 gave the highest PPV (81%). Using the RT-nPCR as the gold standard, the ELISA had an accuracy of 91.7% when using a cut off >0.75 as a positive result. When compared with the ELISA, the HA had an accuracy of 73% when using an HA titre cut off greater than 16 as a positive result. These results indicate that alternative tests for GAV (ELISA and HA) can be used to explore multiple questions about the disease status of P. monodon stocks in a cost-effective manner. [source] Basis of metamemory judgments for text with multiple-choice, essay and recall tests,APPLIED COGNITIVE PSYCHOLOGY, Issue 2 2009Ruth H. Maki Accuracy of metamemory for text was compared for multiple-choice, essay and recall tests. Essay and recall tests were scored with Latent Semantic Analysis (LSA), number of correct idea units and number of word matches. Each measure was correlated with college students' predictions and posttest confidence judgments across texts to determine metamemory accuracy. Metamemory accuracy varied for different types of tests with multiple-choice tests generally producing greater accuracy than essay tests. However, metamemory accuracy for essay and recall tests depended on the measure used to score them. Number of correct idea units produced the highest metamemory accuracy, word matches produced an intermediate level, and LSA produced the lowest accuracy. Students used the quantity of output in their judgments, so performance measures that related most strongly to quantity matched judgments better than measures based on answer quality. The results are compatible with an accessibility account of judgments about performance on text. Copyright © 2008 John Wiley & Sons, Ltd. [source] Utility of diagnostic tests in the follow-up of egg-allergic childrenCLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2009Ma C. Diéguez Summary Background Better knowledge of the accuracy of a skin prick test (SPT) and specific IgE (sIgE) levels to egg allergens would help to identify persistent egg-allergic children, avoiding unnecessary risky challenges. This study was designed to assess the accuracy of a SPT and sIgE levels to egg allergens in order to determine persistent egg allergy in IgE-mediated allergic children after an egg-free diet. Methods Children below 16 years were prospectively and consecutively recruited. Inclusion criteria were: allergy to egg proteins (children with a positive clinical case of IgE-mediated egg allergy and a positive SPT to egg allergens and/or positive sIgE levels), and strict egg avoidance diet followed for at least 6 months. Clinical histories were recorded and all patients underwent SPTs, sIgE levels to egg allergens and the gold standard -a double-blind placebo-controlled egg challenge (DBPCFG). DBPCFG was interpreted without knowledge of the results of the other tests and vice-versa. A SPT and sIgE levels' ROC curves analysis was performed to compare the diagnostic performance of the different tests. Results Finally, 157 children were included in the study. One hundred out of these 157 children (63.7%) had a positive oral challenge. Ninety-six were male (61%), and the median age was 2.5 years. One hundred and three (66.9%) had atopic dermatitis. A 7 mm egg white prick test had a positive likelihood ratio (+LR) of 6.7, and a level of 1.3 KU/L egg white-sIgE had a +LR of 5.1. A 7 mm egg white SPT had a positive predictive value of 92.3% (95% CI 85.1,99.5), and for a 9 mm egg white SPT this value was 95.6% (95% CI 87.3,100.0). For egg white-sIgE, 1.5 KU/L had a positive predictive value of 90.4% (95% CI 82.4,98.4) and for 25 KU/L it was 100.0% (95% CI 100.0,100.0). SPTs with ovotransferrin and lysozyme showed the lowest accuracy, followed by yolk and ovalbumin SPTs. Conclusion This study is the first to evaluate both tests (SPT and sIgE levels) and all egg allergens to determine the persistence of egg allergy in IgE-mediated allergic children. Measuring the SPT and sIgE levels is useful to predict persistent allergy in these children, especially with the egg white complete extract. An oral challenge should not be performed in egg allergic paediatric patients with either an egg white prick test above 7 mm or a white egg-sIgE determination above 1.3 KU/L, because there is a 90% probability of remaining allergic. [source] | ||||||||||