Test performance study of diagnostic procedures for identification and detection ofGibberella circinatain pine seeds in the framework of a EUPHRESCO project

AbstractTilletia controversa causing dwarf bunt of wheat is a quarantine pathogen in several countries. Therefore, its specific detection is of great phytosanitary importance. Genomic regions routinely used for phylogenetic inferences lack suitable polymorphisms for the development of species-specific markers. We therefore compared 21 genomes of six Tilletia species to identify DNA regions that were unique and conserved in all T. controversa isolates and had no or limited homology to other Tilletia species. A loop-mediated isothermal amplification (LAMP) assay for T. controversa was developed based on one of these DNA regions. The specificity of the assay was verified using 223 fungal samples comprising 43 fungal species including 11 Tilletia species, in particular 39 specimens of T. controversa, 92 of T. caries and 40 of T. laevis, respectively. The assay specifically amplified genomic DNA of T. controversa from pure cultures and teliospores. Only Tilletia trabutii generated false positive signals. The detection limit of the LAMP assay was 5 pg of genomic DNA per reaction. A test performance study that included five laboratories in Germany resulted in 100% sensitivity and 97.7% specificity of the assay. Genomic regions, specific to common bunt (Tilletia caries and Tilletia laevis together) are also provided.

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Accuracy of D-Dimers to Rule Out Venous Thromboembolism Events across Age Categories

Emergency Medicine International ◽

10.1155/2010/185453 ◽

2010 ◽

Vol 2010 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

G. Der Sahakian ◽

Y. E. Claessens ◽

J. C. Allo ◽

J. Kansao ◽

G. Kierzek ◽

...

Keyword(s):

Venous Thromboembolism ◽

Test Performance ◽

High Sensitivity ◽

Diagnostic Procedures ◽

Dependent Manner ◽

Intermediate Risk ◽

Risk Patients ◽

Thromboembolism Events ◽

High Level ◽

Rule Out

Background. Strategies combining pretest clinical assessment and D-dimers measurement efficiently and safely rule out venous thromboembolism events (VTE) in low- and intermediate-risk patients.Objectives. As process of ageing is associated with altered concentrations of coagulation markers including an increase in D-dimers levels, we investigated whether D-dimers could reliably rule out VTE across age categories.Method. We prospectively assessed the test performance in 1,004 patients visiting the emergency department during the 6-month period with low or intermediate risk of VTE who also received additional diagnostic procedures.Results. 67 patients had VTE with D-dimers levels above the threshold, and 3 patients displayed D-dimers levels below the threshold. We observed that specificity of D-dimers test decreased in an age-dependent manner. However, sensitivity and negative predictive value remained at very high level in each age category including older patients.Conclusion. We conclude that, even though D-dimers level could provide numerous false positive results in elderly patients, its high sensitivity could reliably help physicians to exclude the diagnosis of VTE in every low- and intermediate-risk patient.

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Point of care testing using rapid automated antigen testing for SARS-COV-2 in care homes – an exploratory safety, usability and diagnostic agreement evaluation

Journal of Patient Safety and Risk Management ◽

10.1177/25160435211054207 ◽

2021 ◽

pp. 251604352110542

Author(s):

Massimo Micocci ◽

Peter Buckle ◽

Gail Hayward ◽

A Joy Allen ◽

Kerrie Davies ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Care Home ◽

Immunofluorescence Assay ◽

Careful Consideration ◽

Care Homes ◽

Performance Study ◽

Post Modification ◽

Point Of Care Tests ◽

Positive Agreement

Introduction Successful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of the contextual and usability factors that affect test results and minimise biosafety risks. This paper presents a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes. Methods A mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was conducted to explore biosafety issues. Results The agreement analysis was conducted on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI:1.3%−98.7%) positive agreement and 96% (95% CI: 92.5%−98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857−0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%−99.6%) positive agreement and 100% (95% CI: 63.1%−100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549−1). The dry run highlighted four main sources of contamination that led to the modification of the standard operating procedures. Simulation post-modification showed no further evidence of contamination. Conclusion Careful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

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Point of Care Testing using rapid automated Antigen Testing for SARS-COV-2 in Care Homes – an exploratory safety, usability and diagnostic agreement evaluation

10.1101/2021.04.22.21255948 ◽

2021 ◽

Author(s):

Massimo Micocci ◽

Peter Buckle ◽

Gail Hayward ◽

A. Joy Allen ◽

Kerrie Davies ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Care Home ◽

Immunofluorescence Assay ◽

Careful Consideration ◽

Care Homes ◽

Performance Study ◽

Mixed Methods Evaluation ◽

Point Of Care Tests ◽

Positive Agreement

AbstractIntroductionSuccessful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of contextual and usability factors that affect test results and minimise biosafety risks. This paper presents findings from a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes.MethodsA mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was carried out to explore biosafety issues.ResultsThe agreement analysis was carried out on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI: 1.3%-98.7%) positive agreement and 96% (95% CI: 92.5%-98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857-0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%-99.6%) positive agreement and 100% (95% CI: 63.1%-100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549-1).The dry run showed four main sources of contamination that led to the modification of the standard operating procedures. Simulation after modification showed no further evidence of contamination.ConclusionCareful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

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Performance Validity and Symptom Validity in Neuropsychological Assessment

Journal of the International Neuropsychological Society ◽

10.1017/s1355617712000240 ◽

2012 ◽

Vol 18 (4) ◽

pp. 625-630 ◽

Cited By ~ 197

Author(s):

Glenn J. Larrabee

Keyword(s):

Test Performance ◽

False Positive ◽

Neuropsychological Test ◽

Diagnostic Procedures ◽

Individual Case ◽

Effect Sizes ◽

Symptom Validity ◽

Performance Validity ◽

Symptom Report ◽

The Individual

AbstractFailure to evaluate the validity of an examinee's neuropsychological test performance can alter prediction of external criteria in research investigations, and in the individual case, result in inaccurate conclusions about the degree of impairment resulting from neurological disease or injury. The terms performance validity referring to validity of test performance (PVT), and symptom validity referring to validity of symptom report (SVT), are suggested to replace less descriptive terms such as effort or response bias. Research is reviewed demonstrating strong diagnostic discrimination for PVTs and SVTs, with a particular emphasis on minimizing false positive errors, facilitated by identifying performance patterns or levels of performance that are atypical for bona fide neurologic disorder. It is further shown that false positive errors decrease, with a corresponding increase in the positive probability of malingering, when multiple independent indicators are required for diagnosis. The rigor of PVT and SVT research design is related to a high degree of reproducibility of results, and large effect sizes of d=1.0 or greater, exceeding effect sizes reported for several psychological and medical diagnostic procedures. (JINS, 2012, 18, 1–7)

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DNA barcoding as an identification tool for selected EU-regulated plant pests: an international collaborative test performance study among 14 laboratories

EPPO Bulletin ◽

10.1111/epp.12031 ◽

2013 ◽

Vol 43 (2) ◽

pp. 216-228 ◽

Cited By ~ 8

Author(s):

B. T. L. H. van de Vossenberg ◽

M. Westenberg ◽

P. J. M. Bonants

Keyword(s):

Dna Barcoding ◽

Test Performance ◽

Performance Study ◽

Plant Pests ◽

Collaborative Test ◽

International Collaborative ◽

Identification Tool

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Test performance study of isothermal amplification tests for the detection of Grapevine flavescence dorée phytoplasma and ‘ Candidatus Phytoplasma solani’

EPPO Bulletin ◽

10.1111/epp.12351 ◽

2017 ◽

Vol 47 (1) ◽

pp. 18-23 ◽

Cited By ~ 2

Author(s):

N. Mehle ◽

P. Kogovšek ◽

F. Constable ◽

K. De Jonghe ◽

M. Loiseau ◽

...

Keyword(s):

Test Performance ◽

Isothermal Amplification ◽

Performance Study ◽

Flavescence Dorée

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Assessment of a new qPCR tool for the detection and identification of the root-knot nematode Meloidogyne enterolobii by an international test performance study

European Journal of Plant Pathology ◽

10.1007/s10658-015-0754-0 ◽

2015 ◽

Vol 144 (1) ◽

pp. 97-108 ◽

Cited By ~ 13

Author(s):

Andrea Braun-Kiewnick ◽

Nicole Viaene ◽

Laurent Folcher ◽

Fabrice Ollivier ◽

Géraldine Anthoine ◽

...

Keyword(s):

Test Performance ◽

Performance Study ◽

Root Knot Nematode ◽

Detection And Identification ◽

Meloidogyne Enterolobii

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Setting clinical performance specifications to develop and evaluate biomarkers for clinical use

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/0004563219842265 ◽

2019 ◽

Vol 56 (5) ◽

pp. 527-535 ◽

Cited By ~ 7

Author(s):

Sarah J Lord ◽

Andrew St John ◽

Patrick MM Bossuyt ◽

Sverre Sandberg ◽

Phillip J Monaghan ◽

...

Keyword(s):

Test Performance ◽

False Positive ◽

Biomarker Discovery ◽

Clinical Performance ◽

False Negative ◽

Performance Study ◽

Negative Results ◽

False Negative Results ◽

Performance Specifications ◽

Statistical Hypotheses

Background Biomarker discovery studies often claim ‘promising’ findings, motivating further studies and marketing as medical tests. Unfortunately, the patient benefits promised are often inadequately explained to guide further evaluation, and few biomarkers have translated to improved patient care. We present a practical guide for setting minimum clinical performance specifications to strengthen clinical performance study design and interpretation. Methods We developed a step-by-step approach using test evaluation and decision-analytic frameworks and present with illustrative examples. Results We define clinical performance specifications as a set of criteria that quantify the clinical performance a new test must attain to allow better health outcomes than current practice. We classify the proposed patient benefits of a new test into three broad groups and describe how to set minimum clinical performance at the level where the potential harm of false-positive and false-negative results does not outweigh the benefits. (1) For add-on tests proposed to improve disease outcomes by improving detection, define an acceptable trade-off for false-positive versus true-positive results; (2) for triage tests proposed to reduce unnecessary tests and treatment by ruling out disease, define an acceptable risk of false-negatives as a safety threshold; (3) for replacement tests proposed to provide other benefits, or reduce costs, without compromising accuracy, use existing tests to benchmark minimum accuracy levels. Conclusions Researchers can follow these guidelines to focus their study objectives and to define statistical hypotheses and sample size requirements. This way, clinical performance studies will allow conclusions about whether test performance is sufficient for intended use.

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