Search results for "diagnostic test"

On implementation of the Gibbs sampler for estimating the accuracy of multiple diagnostic tests

2010

Implementation of the Gibbs sampler for estimating the accuracy of multiple binary diagnostic tests in one population has been investigated. This method, proposed by Joseph, Gyorkos and Coupal, makes use of a Bayesian approach and is used in the absence of a gold standard to estimate the prevalence, the sensitivity and specificity of medical diagnostic tests. The expressions that allow this method to be implemented for an arbitrary number of tests are given. By using the convergence diagnostics procedure of Raftery and Lewis, the relation between the number of iterations of Gibbs sampling and the precision of the estimated quantiles of the posterior distributions is derived. An example conc…

Early Response to treatment in Eating Disorders: A Systematic Review and a Diagnostic Test Accuracy Meta-Analysis

2016

Objective: Early response to eating disorders treatment is thought to predict a later favourable outcome. A systematic review of the literature and meta-analyses examined the robustness of this concept. Method: The criteria used across studies to define early response were summarised following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Diagnostic Test Accuracy methodology was used to estimate the size of the effect. Results: Findings from 24 studies were synthesized and data from 14 studies were included in the meta-analysis. In Anorexia Nervosa, the odds ratio of early response predicting remission was 4.85(95%CI: 2.94–8.01) and the summary Area Unde…

Validation of Loop-Mediated Isothermal Amplification (LAMP) Field Tool for Rapid and Sensitive Diagnosis of Contagious Agalactia in Small Ruminants

2020

Simple Summary Contagious agalactia (CA) is an infectious disease of small ruminants endemic in the Mediterranean countries, causing significant socioeconomic impacts predominantly on small-scale farmers who still subsist on marginal lands. Mycoplasma agalactiae is historically considered the principal etiological agent of CA, especially in sheep. Clinical signs are characterised by mastitis, arthritis, keratoconjunctivitis and occasionally, abortion. Rapid, accurate and cost-effective field tests are urgently needed for effective control of M. agalactiae mastitis. Our study illustrated the validation of a Loop-Mediated Isothermal Amplification (LAMP) test for the detection of M. agalactiae…

Overdispersion tests in count-data analysis.

2008

Count data are commonly assumed to have a Poisson distribution, especially when there is no diagnostic procedure for checking this assumption. However, count data rarely fit the restrictive assumptions of the Poisson distribution. The violation of much of such assumptions commonly results in overdispersion, which invalidates the Poisson distribution. Undetected overdispersion may entail important misleading inferences, so its detection is essential. In this study, different overdispersion diagnostic tests are evaluated through two simulation studies. In Exp. 1, the nominal error rate is compared under different sample sizes and Λ conditions. Analysis shows a remarkable performance of the χ…

Bayesian Analysis of Diagnostic Accuracy for Gastroesophageal Reflux Disease in the absence of gold standard

2007

Metodo per la genotipizzazione di HIV-1 e relativi kit diagnostici per la rilevazione di farmaco-resistenza (gene ENV-gp41).

2007

DESCRIPTION OF THE INVENTION This invention concerns a laboratory method for genotyping human immunodeficiency virus type 1 (HIV-1) through gene sequencing of gp41-env. It allows to detect the nucleotide mutations conferring resistance to antiretroviral drugs active to gp41-env. The present method allows to analyze also low viraemia samples at around 101 -102 copies HIV-RNA/ml. This method offers the advantage of being easily adaptable to both plasma and cellular samples and is therefore able to value "in advance" the genetic mutations potentially involved in the resistance phenomena to anti-retroviral drugs, even in patients with optimal/sub-optimal virologic control. The kit use the one-s…

Metodo per la genotipizzazione di HIV-1 e relativi kit diagnostici per la rilevazione di farmaco-resistenza (geni GAG/POL).

2007

DESCRIPTION OF THE INVENTION This invention concerns a laboratory method for genotyping human immunodeficiency virus type 1 (HIV-1) through gene sequencing of pol. It allows to detect the nucleotide mutations conferring resistance to antiretroviral drugs active to pol. The present method allows to analyze also low viraemia samples at around 101 -102 copies HIV-RNA/ml. This method offers the advantage of being easily adaptable to both plasma and cellular samples and is therefore able to value "in advance" the genetic mutations potentially involved in the resistance phenomena to anti-retroviral drugs, even in patients with optimal/sub-optimal virologic control. The kit use the one-step RT-PCR…

Fabry Disease, a Complex Pathology Not Easy to Diagnose

2015

Fabry disease is a multisystemic lysosomal storage disorder, inherited in an X-linked manner. It is a defect of metabolism of the glycosphingolipids, due to the reduction or absence of the activity of lysosomal enzyme α-galactosidase A. This reduction of activity causes the storage of globotriaosylceramide and derivatives in the lysosomes, triggering a cascade of cellular events, mainly in vascular endothelium. These events are the responsible for the systemic clinical manifestations and the renal, cardiac and cerebrovascular complications, or a combination of them. The symptomatology can lead to the premature death of patient between the fourth or fifth decade of life. The first symptoms c…

Laboratory testing in the emergency department: an Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC) and Academy of Em…

2018

Abstract Background: The mainstay of patient-oriented laboratory testing in emergency settings entails selecting a number and the type of tests according to valid criteria of appropriateness. Since the pattern of urgent tests requesting is variable across different institutions, we designed a joined survey between the Academy of Emergency Medicine and Care (AcEMC) and the Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC) for reaching tentative consensus about the most informative diagnostic tests in emergency settings. Methods: A survey, containing the most commonly ordered urgent laboratory tests and the relative clinical indications, was disseminated to eigh…

Suspected Nonceliac Gluten Sensitivity Confirmed in Few Patients After Gluten Challenge in Double-Blind, Placebo-Controlled Trials

2017

A double-blind, placebo-controlled, gluten challenge has been proposed to confirm a diagnosis of non-celiac gluten sensitivity (NCGS) in patients without celiac disease who respond to a gluten-free diet. To determine the accuracy of this approach, we analyzed data from 10 double-blind, placebo-controlled, gluten challenge trials, comprising 1312 adults. The studies varied in the duration of the challenge (ranging from 1 day to 6 weeks), daily doses for the gluten challenge (ranging from 2 g to 52 g; 3 studies administered less than 8 g/day), and composition of the placebo (gluten-free products, xylose, whey protein, rice, or corn starch containing fermentable carbohydrates). Most of the stu…