Accurate Diagnostic Tests (accurate + diagnostic_test)

Distribution by Scientific Domains


Selected Abstracts


Profile-Likelihood Inference for Highly Accurate Diagnostic Tests

BIOMETRICS, Issue 4 2002
John V. Tsimikas
Summary. We consider profile-likelihood inference based on the multinomial distribution for assessing the accuracy of a diagnostic test. The methods apply to ordinal rating data when accuracy is assessed using the area under the receiver operating characteristic (ROC) curve. Simulation results suggest that the derived confidence intervals have acceptable coverage probabilities, even when sample sizes are small and the diagnostic tests have high accuracies. The methods extend to stratified settings and situations in which the ratings are correlated. We illustrate the methods using data from a clinical trial on the detection of ovarian cancer. [source]


Evaluation of PG-M3 antibody in the diagnosis of acute promyelocytic leukaemia

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2010
Sanjeev Kumar Gupta
Eur J Clin Invest 2010; 40 (10): 960,962 Abstract Background & objectives, Acute promyelocytic leukaemia (APL) is a distinct subtype of acute myeloid leukaemia (AML) characterized by a reciprocal translocation, t(15;17) and a high incidence of life-threatening coagulopathy. APL diagnosis is considered a medical emergency. As reverse transcription-polymerase chain reaction (RT-PCR) for PML-RAR, fusion oncoprotein is time consuming, there is a need for a rapid and accurate diagnostic test for APL. This study evaluates the role of PG-M3 monoclonal antibody using immunofluorescence (IF) in the early diagnosis of APL. Materials and Methods, Thirty-six new untreated APL cases diagnosed with RT-PCR for PML-RAR, as the gold standard and 38 non-APL controls (28 non-APL AMLs and 10 non-leukaemic samples) were evaluated by routine morphology and cytochemistry, RT-PCR and IF using PG-M3 monoclonal antibody. Results, Using IF, 34 of 36 (94·4%) APL cases showed a microgranular pattern suggestive of APL and two cases (5·6%) showed a speckled pattern typical of wild-type PML protein (False negative). By comparison, two of 28 (7·1%) non-APL AMLs showed microgranular pattern (false positive). Hence, IF as a diagnostic test for APL resulted in a sensitivity of 94·4%, specificity of 92·9% and positive and negative predictive values of 94·4% and 92·9% respectively. All 10 non-leukaemic samples showed a speckled pattern. Conclusions, IF using PG-M3 antibodies can be used as a rapid (takes 2 h), cheap, sensitive and specific method to identify APL. It can be a useful adjunct for diagnosis of APL especially if facilities for RT-PCR are not available, particularly in resource-limited settings. [source]


Role of Contrast Echocardiography in the Assessment of Myocardial Rupture

ECHOCARDIOGRAPHY, Issue 1 2003
Sumit Mittle M.D.
Left ventricular free wall rupture is known to complicate acute myocardial infarction and is the second most common cause of inhospital mortality in this patient population. Contrary to widely held medical belief, this does not always result in immediate fatal pericardial tamponade with hemodynamic collapse. Up to 40% of such occurrences are subacute and may evolve over hours or even days. A high index of suspicion and accurate diagnostic tests are required to identify and treat these patients with emergent surgery. Echocardiography has emerged as an important diagnostic modality to identify this catastrophic condition. Although the literature has scattered reports on the role of transesophageal and transthoracic echocardiography in diagnosing free wall rupture, to date, only one report in the literature used ultrasound contrast agents to better delineate echocardiographic findings. We will present two cases in which echocardiography with use of intravenous ultrasound contrast agents was instrumental in helping to exclude rupture in one case and help identify rupture in another. (ECHOCARDIOGRAPHY, Volume 20, January 2003) [source]


Cerebrospinal fluid brain-derived proteins in the diagnosis of Alzheimer's disease and Creutzfeldt,Jakob disease

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 6 2002
A. J. E. GreenArticle first published online: 24 NOV 200
The differential diagnosis of dementia can be difficult in the early stages of disease, and with the emergence of new therapeutic agents for Alzheimer's disease (AD) there is an increasing need for reliable and accurate diagnostic tests. The concept of brain-specific proteins was first proposed in the 1960s and, since that time, methods have developed to measure these proteins in the cerebrospinal fluid (CSF). The concentration of individual brain-specific proteins can be altered in disease, and these changes are thought to reflect the underlying pathology. CSF tau protein and amyloid peptide A,42 concentrations are altered in AD and have been proposed as early diagnostic tests for this disease. The data from a number of studies suggest that these proteins may be of value, but are less specific than previously thought and further studies with neuropathological confirmation are required before these tests can be introduced into clinical practice. The detection of 14-3-3 in the CSF is an accurate test for sporadic Creutzfeldt,Jakob disease (CJD) and this accuracy has lead the World Health Organization to revise the clinical criteria for probable sporadic CJD to include a positive CSF 14-3-3. However, CSF 14-3-3 is less useful in the diagnosis of variant CJD, where studies are underway investigating the value of other CSF proteins. [source]