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Sample records for accurate diagnostic tests

  1. Optimizing odor identification testing as quick and accurate diagnostic tool for Parkinson's disease

    PubMed Central

    Mahlknecht, Philipp; Pechlaner, Raimund; Boesveldt, Sanne; Volc, Dieter; Pinter, Bernardette; Reiter, Eva; Müller, Christoph; Krismer, Florian; Berendse, Henk W.; van Hilten, Jacobus J.; Wuschitz, Albert; Schimetta, Wolfgang; Högl, Birgit; Djamshidian, Atbin; Nocker, Michael; Göbel, Georg; Gasperi, Arno; Kiechl, Stefan; Willeit, Johann; Poewe, Werner

    2016-01-01

    ABSTRACT Introduction The aim of this study was to evaluate odor identification testing as a quick, cheap, and reliable tool to identify PD. Methods Odor identification with the 16‐item Sniffin' Sticks test (SS‐16) was assessed in a total of 646 PD patients and 606 controls from three European centers (A, B, and C), as well as 75 patients with atypical parkinsonism or essential tremor and in a prospective cohort of 24 patients with idiopathic rapid eye movement sleep behavior disorder (center A). Reduced odor sets most discriminative for PD were determined in a discovery cohort derived from a random split of PD patients and controls from center A using L1‐regularized logistic regression. Diagnostic accuracy was assessed in the rest of the patients/controls as validation cohorts. Results Olfactory performance was lower in PD patients compared with controls and non‐PD patients in all cohorts (each P < 0.001). Both the full SS‐16 and a subscore of the top eight discriminating odors (SS‐8) were associated with an excellent discrimination of PD from controls (areas under the curve ≥0.90; sensitivities ≥83.3%; specificities ≥82.0%) and from non‐PD patients (areas under the curve ≥0.91; sensitivities ≥84.1%; specificities ≥84.0%) in all cohorts. This remained unchanged when patients with >3 years of disease duration were excluded from analysis. All 8 incident PD cases among patients with idiopathic rapid eye movement sleep behavior disorder were predicted with the SS‐16 and the SS‐8 (sensitivity, 100%; positive predictive value, 61.5%). Conclusions Odor identification testing provides excellent diagnostic accuracy in the distinction of PD patients from controls and diagnostic mimics. A reduced set of eight odors could be used as a quick tool in the workup of patients presenting with parkinsonism and for PD risk indication. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and

  2. Accurate, fast and cost-effective diagnostic test for monosomy 1p36 using real-time quantitative PCR.

    PubMed

    Cunha, Pricila da Silva; Pena, Heloisa B; D'Angelo, Carla Sustek; Koiffmann, Celia P; Rosenfeld, Jill A; Shaffer, Lisa G; Stofanko, Martin; Gonçalves-Dornelas, Higgor; Pena, Sérgio Danilo Junho

    2014-01-01

    Monosomy 1p36 is considered the most common subtelomeric deletion syndrome in humans and it accounts for 0.5-0.7% of all the cases of idiopathic intellectual disability. The molecular diagnosis is often made by microarray-based comparative genomic hybridization (aCGH), which has the drawback of being a high-cost technique. However, patients with classic monosomy 1p36 share some typical clinical characteristics that, together with its common prevalence, justify the development of a less expensive, targeted diagnostic method. In this study, we developed a simple, rapid, and inexpensive real-time quantitative PCR (qPCR) assay for targeted diagnosis of monosomy 1p36, easily accessible for low-budget laboratories in developing countries. For this, we have chosen two target genes which are deleted in the majority of patients with monosomy 1p36: PRKCZ and SKI. In total, 39 patients previously diagnosed with monosomy 1p36 by aCGH, fluorescent in situ hybridization (FISH), and/or multiplex ligation-dependent probe amplification (MLPA) all tested positive on our qPCR assay. By simultaneously using these two genes we have been able to detect 1p36 deletions with 100% sensitivity and 100% specificity. We conclude that qPCR of PRKCZ and SKI is a fast and accurate diagnostic test for monosomy 1p36, costing less than 10 US dollars in reagent costs.

  3. Accurate, Fast and Cost-Effective Diagnostic Test for Monosomy 1p36 Using Real-Time Quantitative PCR

    PubMed Central

    Cunha, Pricila da Silva; Pena, Heloisa B.; D'Angelo, Carla Sustek; Koiffmann, Celia P.; Rosenfeld, Jill A.; Shaffer, Lisa G.; Stofanko, Martin; Gonçalves-Dornelas, Higgor; Pena, Sérgio Danilo Junho

    2014-01-01

    Monosomy 1p36 is considered the most common subtelomeric deletion syndrome in humans and it accounts for 0.5–0.7% of all the cases of idiopathic intellectual disability. The molecular diagnosis is often made by microarray-based comparative genomic hybridization (aCGH), which has the drawback of being a high-cost technique. However, patients with classic monosomy 1p36 share some typical clinical characteristics that, together with its common prevalence, justify the development of a less expensive, targeted diagnostic method. In this study, we developed a simple, rapid, and inexpensive real-time quantitative PCR (qPCR) assay for targeted diagnosis of monosomy 1p36, easily accessible for low-budget laboratories in developing countries. For this, we have chosen two target genes which are deleted in the majority of patients with monosomy 1p36: PRKCZ and SKI. In total, 39 patients previously diagnosed with monosomy 1p36 by aCGH, fluorescent in situ hybridization (FISH), and/or multiplex ligation-dependent probe amplification (MLPA) all tested positive on our qPCR assay. By simultaneously using these two genes we have been able to detect 1p36 deletions with 100% sensitivity and 100% specificity. We conclude that qPCR of PRKCZ and SKI is a fast and accurate diagnostic test for monosomy 1p36, costing less than 10 US dollars in reagent costs. PMID:24839341

  4. Panel-based Genetic Diagnostic Testing for Inherited Eye Diseases is Highly Accurate and Reproducible and More Sensitive for Variant Detection Than Exome Sequencing

    PubMed Central

    Bujakowska, Kinga M.; Sousa, Maria E.; Fonseca-Kelly, Zoë D.; Taub, Daniel G.; Janessian, Maria; Wang, Dan Yi; Au, Elizabeth D.; Sims, Katherine B.; Sweetser, David A.; Fulton, Anne B.; Liu, Qin; Wiggs, Janey L.; Gai, Xiaowu; Pierce, Eric A.

    2015-01-01

    Purpose Next-generation sequencing (NGS) based methods are being adopted broadly for genetic diagnostic testing, but the performance characteristics of these techniques have not been fully defined with regard to test accuracy and reproducibility. Methods We developed a targeted enrichment and NGS approach for genetic diagnostic testing of patients with inherited eye disorders, including inherited retinal degenerations, optic atrophy and glaucoma. In preparation for providing this Genetic Eye Disease (GEDi) test on a CLIA-certified basis, we performed experiments to measure the sensitivity, specificity, reproducibility as well as the clinical sensitivity of the test. Results The GEDi test is highly reproducible and accurate, with sensitivity and specificity for single nucleotide variant detection of 97.9% and 100%, respectively. The sensitivity for variant detection was notably better than the 88.3% achieved by whole exome sequencing (WES) using the same metrics, due to better coverage of targeted genes in the GEDi test compared to commercially available exome capture sets. Prospective testing of 192 patients with IRDs indicated that the clinical sensitivity of the GEDi test is high, with a diagnostic rate of 51%. Conclusion The data suggest that based on quantified performance metrics, selective targeted enrichment is preferable to WES for genetic diagnostic testing. PMID:25412400

  5. BIOACCESSIBILITY TESTS ACCURATELY ESTIMATE ...

    EPA Pesticide Factsheets

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from five Pb-contaminated Superfund sites had relative bioavailabilities from 33%-63%, with a mean of about 50%. Treatment of two of the soils with P significantly reduced the bioavailability of Pb. The bioaccessibility of the Pb in the test soils was then measured in six in vitro tests and regressed on bioavailability. They were: the “Relative Bioavailability Leaching Procedure” (RBALP) at pH 1.5, the same test conducted at pH 2.5, the “Ohio State University In vitro Gastrointestinal” method (OSU IVG), the “Urban Soil Bioaccessible Lead Test”, the modified “Physiologically Based Extraction Test” and the “Waterfowl Physiologically Based Extraction Test.” All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the RBALP pH 2.5 and OSU IVG tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter 24%, or present as Pb sulfate 18%. Ad

  6. Prenatal Genetic Diagnostic Tests

    MedlinePlus

    ... Education & Events Advocacy For Patients About ACOG Prenatal Genetic Diagnostic Tests Home For Patients Search FAQs Prenatal ... Pamphlets - Spanish FAQ164, September 2016 PDF Format Prenatal Genetic Diagnostic Tests Pregnancy What is prenatal genetic testing? ...

  7. What Is Diagnostic Testing?

    MedlinePlus

    ... Primary care providers Specialists Getting covered Research Basic science research Research in people ... screening Diagnostic testing Direct-to-consumer genetic testing Newborn screening Pharmacogenomic testing ...

  8. Rapid diagnostic tests for malaria.

    PubMed

    Visser, Theodoor; Daily, Jennifer; Hotte, Nora; Dolkart, Caitlin; Cunningham, Jane; Yadav, Prashant

    2015-12-01

    Maintaining quality, competitiveness and innovation in global health technology is a constant challenge for manufacturers, while affordability, access and equity are challenges for governments and international agencies. In this paper we discuss these issues with reference to rapid diagnostic tests for malaria. Strategies to control and eliminate malaria depend on early and accurate diagnosis. Rapid diagnostic tests for malaria require little training and equipment and can be performed by non-specialists in remote settings. Use of these tests has expanded significantly over the last few years, following recommendations to test all suspected malaria cases before treatment and the implementation of an evaluation programme to assess the performance of the malaria rapid diagnostic tests. Despite these gains, challenges exist that, if not addressed, could jeopardize the progress made to date. We discuss recent developments in rapid diagnostic tests for malaria, highlight some of the challenges and provide suggestions to address them.

  9. Diagnostic limitations to accurate diagnosis of cholera.

    PubMed

    Alam, Munirul; Hasan, Nur A; Sultana, Marzia; Nair, G Balakrish; Sadique, A; Faruque, A S G; Endtz, Hubert P; Sack, R B; Huq, A; Colwell, R R; Izumiya, Hidemasa; Morita, Masatomo; Watanabe, Haruo; Cravioto, Alejandro

    2010-11-01

    The treatment regimen for diarrhea depends greatly on correct diagnosis of its etiology. Recent diarrhea outbreaks in Bangladesh showed Vibrio cholerae to be the predominant cause, although more than 40% of the suspected cases failed to show cholera etiology by conventional culture methods (CMs). In the present study, suspected cholera stools collected from every 50th patient during an acute diarrheal outbreak were analyzed extensively using different microbiological and molecular tools to determine their etiology. Of 135 stools tested, 86 (64%) produced V. cholerae O1 by CMs, while 119 (88%) tested positive for V. cholerae O1 by rapid cholera dipstick (DS) assay; all but three samples positive for V. cholerae O1 by CMs were also positive for V. cholerae O1 by DS assay. Of 49 stools that lacked CM-based cholera etiology despite most being positive for V. cholerae O1 by DS assay, 25 (51%) had coccoid V. cholerae O1 cells as confirmed by direct fluorescent antibody (DFA) assay, 36 (73%) amplified primers for the genes wbe O1 and ctxA by multiplex-PCR (M-PCR), and 31 (63%) showed El Tor-specific lytic phage on plaque assay (PA). Each of these methods allowed the cholera etiology to be confirmed for 97% of the stool samples. The results suggest that suspected cholera stools that fail to show etiology by CMs during acute diarrhea outbreaks may be due to the inactivation of V. cholerae by in vivo vibriolytic action of the phage and/or nonculturability induced as a host response.

  10. Toxoplasma gondii: history and diagnostic test development.

    PubMed

    Wyrosdick, Heidi M; Schaefer, John J

    2015-12-01

    Toxoplasma gondii is a protozoa that causes toxoplasmosis in people and other animals. It is considered one of the most common parasitic infections in the world due to its impressive range of hosts, widespread environmental contamination and the diverse means by which animals can be infected. Despite its ubiquity and numerous ongoing research efforts into both its basic biology and clinical management, many aspects of diagnosis and management of this disease are poorly understood. The range of diagnostic options that is available for veterinary diagnostic investigators are notably more limited than those available to medical diagnosticians, making accurate interpretation of each test result critical. The current review joins other reviews on the parasite with a particular emphasis on the history and continued development of diagnostic tests that are useful for veterinary diagnostic investigations. An understanding of the strengths and shortcomings of current diagnostic techniques will assist veterinary and public health officials in formulating effective treatment and control strategies in diverse animal populations.

  11. 42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions. 410.32 Section 410.32 Public Health CENTERS FOR MEDICARE... (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic...

  12. 42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions. 410.32 Section 410.32 Public Health CENTERS FOR MEDICARE... (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic...

  13. 42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions. 410.32 Section 410.32 Public Health CENTERS FOR MEDICARE... (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic...

  14. 42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions. 410.32 Section 410.32 Public Health CENTERS FOR MEDICARE... (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic...

  15. Anemia: Evaluation and Diagnostic Tests.

    PubMed

    Cascio, Michael J; DeLoughery, Thomas G

    2017-03-01

    Anemia is among the most common medical problems and clinical and laboratory evaluation need to be approached logically. The complete blood count with red cell indices offers clues to diagnosis. Many anemias have characteristic red cell morphology. The reticulocyte count serves as a useful screen for hemolysis or blood loss. Testing for specific causes of the anemia is performed. Occasionally, examination of the bone marrow is required for diagnosis. Molecular testing is increasingly being use to aid the diagnostic process. This article reviews diagnostic tests for anemia and suggests a rational approach to determining the etiology of a patient's anemia.

  16. Evaluation of Commercially Available Serologic Diagnostic Tests for Chikungunya Virus

    PubMed Central

    Flusin, Olivier; Panella, Amanda; Tenebray, Bernard; Lanciotti, Robert; Leparc-Goffart, Isabelle

    2014-01-01

    Chikungunya virus (CHIKV) is present or emerging in dengue virus–endemic areas. Infections caused by these viruses share some common signs/symptoms, but prognosis, patient care, and persistent symptoms differ. Thus, accurate diagnostic methods are essential for differentiating the infections. We evaluated 4 CHIKV serologic diagnostic tests, 2 of which showed poor sensitivity and specificity. PMID:25418184

  17. Diagnostic tests for model structure

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary; Clark, Martyn; Woods, Ross; Bowden, Breck

    2010-05-01

    It is common knowledge that hydrological models based on inappropriate conceptualisations of the catchment can still be calibrated to give good performance in reproducing discharge records. Calibrated models of this type are unsuitable for many of their intended uses. To improve model conceptualisations and allow models to be tailored for individual applications and catchments, modellers need a toolbox of diagnostic tests for model structure. These tests would use a range of field measurements to allow hydrological modellers to test hypotheses about different aspects of model structure. This presentation demonstrates how multiple datasets (rain, flow, soil moisture, tracer studies) can be used to develop perceptual and conceptual models; using a case study in the intensively monitored Mahurangi catchment in New Zealand. Our emphasis is on the use of field data to target individual modelling decisions, and hence to draw conclusions relevant to model building at the catchment scale. The goal is to "bridge the gap" between experimental studies and larger-scale model simulations. The model building decisions are then tested using the FUSE multi-model framework. The framework allows independent control of model choices in representing a range of storages and fluxes. We compare structural diagnostics from field data, realistic and unrealistic model structures, with the aim of untangling the effects of model structure and parameterisation.

  18. Progeria Research Foundation Diagnostic Testing Program

    MedlinePlus

    ... Interview with John Tacket Find the Other 150 Medical Research NEW! Lonafarnib Pre-clinical Drug Supply Program What's ... Scientific Publications Grand Rounds Workshop 2010 Videos Home » Medical Research » Diagnostic Testing The PRF Diagnostic Testing Program The ...

  19. Extremely Early Diagnostic Test for Prostate Cancer

    SciTech Connect

    James, Veronica Jean

    2011-11-17

    This article reports the results of a blinded fiber diffraction study of skin samples taken from TRAMP mice and age-matched controls to determine whether changes noted in fiber diffraction studies of human skin were present in these TRAMP mice studies. These mice are bred to progress to Gleeson Type 3 to Type 5 prostate cancer. Small strips, 1 mm x 5 mm, cut from the mouse skin samples were loaded into cells in the same way as human samples and slightly stretched to remove the crimp. They remained fully hydrated throughout exposure to the synchrotron beam. The added change that was reported for prostate cancer in 2009 was obtained for all TRAMP mice samples, indicating that this change can be read as High Grade Cancer in human diagnostic tests. These changes were evident for all 3 and 7 week old TRAMP mice samples but not for any of the control samples. This indicates that the changes in the fibre diffraction patterns appear much earlier than in any other available prostate cancer diagnostic test, as none of these can verify the presence of prostate cancer in the TRAMP mice before 10 weeks of age. The fiber diffraction test is therefore the most accurate and earliest test for high grade prostate cancer.

  20. Rapid diagnostic tests for malaria ---Haiti, 2010.

    PubMed

    2010-10-29

    Plasmodium falciparum malaria is endemic to Haiti and remains a major concern for residents, including displaced persons, and emergency responders in the aftermath of the January 12, 2010 earthquake. Microscopy has been the only test approved in the national policy for the diagnosis and management of malaria in Haiti; however, the use of microscopy often has been limited by lack of equipment or trained personnel. In contrast, malaria rapid diagnostic tests (RDTs) require less equipment or training to use. To assist in the timely diagnosis and treatment of malaria in Haiti, the Ministry of Public Health and Population (MSPP), in collaboration with CDC, conducted a field assessment that guided the decision to approve the use of RDTs. This data-driven policy change greatly expands the opportunities for accurate malaria diagnosis across the country, allows for improved clinical management of febrile patients, and will improve the quality of malaria surveillance in Haiti.

  1. Development of Dual TaqMan Based One-Step rRT-PCR Assay Panel for Rapid and Accurate Diagnostic Test of MERS-CoV: A Novel Human Coronavirus, Ahead of Hajj Pilgrimage

    PubMed Central

    Hashemzadeh, Mohammad Sadegh; Rasouli, Rahimeh; Zahraei, Bentolhoda; Izadi, Morteza; Tat, Mahdi; Saadat, Seyed Hassan; Najarasl, Mohammad; Khansari Nejad, Behzad; Dorostkar, Ruhollah

    2016-01-01

    Background Coronaviruses (CoVs) are large ribonucleic acid (RNA) viruses causing primarily respiratory disease in humans. A novel human coronavirus, subsequently named middle east respiratory syndrome coronavirus (MERS-CoV), was first reported in Saudi Arabia in September of 2012. With increasing numbers of infections and deaths from MERS-CoV, development of a rapid and reliable kit was crucial to prevent further spread of MERS-CoV. Objectives In this study, we present two real-time reverse-transcription polymerase chain reaction (rRT-PCR) assays for in-house rapid and sensitive diagnostic testing of MERS-CoV, detecting the regions upstream of the envelope gene (upE) and open reading frame (ORF) 1b, respectively, for initial screening and final confirmation of MERS-CoV infection, as recommended by the world health organization (WHO). Materials and Methods In this experimental study, acquiring patient samples was difficult; thus, according to WHO recommendations and standard protocols, we synthesized RNA sequences of upE and ORF1b genes as the template signatures and TaqMan based-diagnostic rRT-PCR assays were carried out using these synthetic genes for detection of MERS-CoV. In this research, we also inaugurated a cell-free system to transcribe these RNA sequences using the DNA templates synthesized. Results The upE and ORF1b based one-step rRT-PCR assays were optimized by testing several times via different synthetic RNAs, and validation results were highly successful. The sensitivity obtained for upE was fewer than ten copies of RNA template per reaction and for ORF1b was 50 or fewer copies per reaction. Conclusions This study showed that the developed rRT-PCR assays are rapid, reliable, reproducible, specific, sensitive, and simple tools for detection of MERS-CoV. Finally, a kit consisting of two assay signatures and controls was assembled, which can be distributed to public health laboratories in Iran to support international MERS-CoV surveillance and public

  2. 9 CFR 93.406 - Diagnostic tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Diagnostic tests. 93.406 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis tests of cattle. Except as provided in paragraph (d) of this section and in §§ 93.418, 93.427(d), and...

  3. 9 CFR 93.406 - Diagnostic tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Diagnostic tests. 93.406 Section 93... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis tests of cattle. Except as provided in paragraph (d) of this section and in §§ 93.418, 93.427(d), and...

  4. Diagnostic testing for Giardia infections.

    PubMed

    Heyworth, Martin F

    2014-03-01

    The traditional method for diagnosing Giardia infections involves microscopic examination of faecal specimens for Giardia cysts. This method is subjective and relies on observer experience. From the 1980s onwards, objective techniques have been developed for diagnosing Giardia infections, and are superseding diagnostic techniques reliant on microscopy. Detection of Giardia antigen(s) by immunoassay is the basis of commercially available diagnostic kits. Various nucleic acid amplification techniques (NAATs) can demonstrate DNA of Giardia intestinalis, and have the potential to become standard approaches for diagnosing Giardia infections. Of such techniques, methods involving either fluorescent microspheres (Luminex) or isothermal amplification of DNA (loop-mediated isothermal amplification; LAMP) are especially promising.

  5. 9 CFR 93.406 - Diagnostic tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis..., ages, markings, and tattoo and eartag numbers. (c) Further tests during quarantine. Ruminants that...

  6. 9 CFR 93.406 - Diagnostic tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis..., ages, markings, and tattoo and eartag numbers. (c) Further tests during quarantine. Ruminants that...

  7. Accurate Point-of-Care Detection of Ruptured Fetal Membranes: Improved Diagnostic Performance Characteristics with a Monoclonal/Polyclonal Immunoassay

    PubMed Central

    Rogers, Linda C.; Scott, Laurie; Block, Jon E.

    2016-01-01

    OBJECTIVE Accurate and timely diagnosis of rupture of membranes (ROM) is imperative to allow for gestational age-specific interventions. This study compared the diagnostic performance characteristics between two methods used for the detection of ROM as measured in the same patient. METHODS Vaginal secretions were evaluated using the conventional fern test as well as a point-of-care monoclonal/polyclonal immunoassay test (ROM Plus®) in 75 pregnant patients who presented to labor and delivery with complaints of leaking amniotic fluid. Both tests were compared to analytical confirmation of ROM using three external laboratory tests. Diagnostic performance characteristics were calculated including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. RESULTS Diagnostic performance characteristics uniformly favored ROM detection using the immunoassay test compared to the fern test: sensitivity (100% vs. 77.8%), specificity (94.8% vs. 79.3%), PPV (75% vs. 36.8%), NPV (100% vs. 95.8%), and accuracy (95.5% vs. 79.1%). CONCLUSIONS The point-of-care immunoassay test provides improved diagnostic accuracy for the detection of ROM compared to fern testing. It has the potential of improving patient management decisions, thereby minimizing serious complications and perinatal morbidity. PMID:27199579

  8. Rapid diagnostic tests for neurological infections in central Africa.

    PubMed

    Yansouni, Cedric P; Bottieau, Emmanuel; Lutumba, Pascal; Winkler, Andrea S; Lynen, Lut; Büscher, Philippe; Jacobs, Jan; Gillet, Philippe; Lejon, Veerle; Alirol, Emilie; Polman, Katja; Utzinger, Jürg; Miles, Michael A; Peeling, Rosanna W; Muyembe, Jean-Jacques; Chappuis, François; Boelaert, Marleen

    2013-06-01

    Infections are a leading cause of life-threatening neuropathology worldwide. In central African countries affected by endemic diseases such as human African trypanosomiasis, tuberculosis, HIV/AIDS, and schistosomiasis, delayed diagnosis and treatment often lead to avoidable death or severe sequelae. Confirmatory microbiological and parasitological tests are essential because clinical features of most neurological infections are not specific, brain imaging is seldom feasible, and treatment regimens are often prolonged or toxic. Recognition of this diagnostic bottleneck has yielded major investment in application of advances in biotechnology to clinical microbiology in the past decade. We review the neurological pathogens for which rapid diagnostic tests are most urgently needed in central Africa, detail the state of development of putative rapid diagnostic tests for each, and describe key technical and operational challenges to their development and implementation. Promising field-suitable rapid diagnostic tests exist for the diagnosis of human African trypanosomiasis and cryptococcal meningoencephalitis. For other infections-eg, syphilis and schistosomiasis-highly accurate field-validated rapid diagnostic tests are available, but their role in diagnosis of disease with neurological involvement is still unclear. For others-eg, tuberculosis-advances in research have not yet yielded validated tests for diagnosis of neurological disease.

  9. Diagnostic Performance of Visual Screening Tests in the Elderly

    NASA Astrophysics Data System (ADS)

    Lança, Carla Costa; Carolino, Elisabete

    2011-09-01

    This study aimed to determine and evaluate the diagnostic accuracy of visual screening tests for detecting vision loss in elderly. This study is defined as study of diagnostic performance. The diagnostic accuracy of 5 visual tests -near convergence point, near accommodation point, stereopsis, contrast sensibility and amsler grid—was evaluated by means of the ROC method (receiver operating characteristics curves), sensitivity, specificity, positive and negative likelihood ratios (LR+/LR-). Visual acuity was used as the reference standard. A sample of 44 elderly aged 76.7 years (±9.32), who were institutionalized, was collected. The curves of contrast sensitivity and stereopsis are the most accurate (area under the curves were 0.814-p = 0.001, C.I.95%[0.653;0.975]— and 0.713-p = 0.027, C.I.95%[0,540;0,887], respectively). The scores with the best diagnostic validity for the stereopsis test were 0.605 (sensitivity 0.87, specificity 0.54; LR+ 1.89, LR-0.24) and 0.610 (sensitivity 0.81, specificity 0.54; LR+ 1.75, LR-0.36). The scores with higher diagnostic validity for the contrast sensibility test were 0.530 (sensitivity 0.94, specificity 0.69; LR+ 3.04, LR-0.09). The contrast sensitivity and stereopsis test's proved to be clinically useful in detecting vision loss in the elderly.

  10. Testing diagnostics of triggered star formation

    NASA Astrophysics Data System (ADS)

    Haworth, Thomas J.; Harries, Tim J.; Acreman, David M.

    2012-10-01

    We produce synthetic images and SEDs from radiation hydrodynamical simulations of radiatively driven implosion. The imaged bright rimmed clouds (BRCs) are morphologically similar to those actually observed in star-forming regions. Using nebular diagnostic optical collisional line ratios, simulated Very Large Array (VLA) radio images, Hα imaging and SED fitting we compute the neutral cloud and ionized boundary layer (IBL) gas densities and temperatures and perform a virial stability analysis for each cloud. We determine that the neutral cloud temperatures derived by SED fitting are hotter than the dominant neutral cloud temperature by 1-2 K due to emission from warm dust. This translates into a change in the calculated cloud mass by 8-35 per cent. Using a constant mass conversion factor (Cν) for BRCs of different class is found to give rise to errors in the cloud mass of up to a factor of 3.6. The IBL electron temperature calculated using diagnostic line ratios is more accurate than assuming the canonical value adopted for radio diagnostics of 104 K. Both radio diagnostics and diagnostic line ratios are found to underestimate the electron density in the IBL. Each system is qualitatively correctly found to be in a state in which the pressure in the IBL is greater than the supporting cloud pressure, implying that the objects are being compressed. We find that observationally derived mass-loss estimates agree with those on the simulation grid and introduce the concept of using the mass-loss flux to give an indication of the relative strength of photoevaporative flow between clouds. The effect of beam size on these diagnostics in radio observations is found to be a mixing of the bright rim and ambient cloud and H II region fluxes, which leads to an underestimate of the cloud properties relative to a control diagnostic.

  11. Instrument accurately measures small temperature changes on test surface

    NASA Technical Reports Server (NTRS)

    Harvey, W. D.; Miller, H. B.

    1966-01-01

    Calorimeter apparatus accurately measures very small temperature rises on a test surface subjected to aerodynamic heating. A continuous thin sheet of a sensing material is attached to a base support plate through which a series of holes of known diameter have been drilled for attaching thermocouples to the material.

  12. Diagnostic methodology is critical for accurately determining the prevalence of ichthyophonus infections in wild fish populations

    USGS Publications Warehouse

    Kocan, R.; Dolan, H.; Hershberger, P.

    2011-01-01

    Several different techniques have been employed to detect and identify Ichthyophonus spp. in infected fish hosts; these include macroscopic observation, microscopic examination of tissue squashes, histological evaluation, in vitro culture, and molecular techniques. Examination of the peer-reviewed literature revealed that when more than 1 diagnostic method is used, they often result in significantly different results; for example, when in vitro culture was used to identify infected trout in an experimentally exposed population, 98.7% of infected trout were detected, but when standard histology was used to confirm known infected tissues from wild salmon, it detected ~50% of low-intensity infections and ~85% of high-intensity infections. Other studies on different species reported similar differences. When we examined a possible mechanism to explain the disparity between different diagnostic techniques, we observed non-random distribution of the parasite in 3-dimensionally visualized tissue sections from infected hosts, thus providing a possible explanation for the different sensitivities of commonly used diagnostic techniques. Based on experimental evidence and a review of the peer-reviewed literature, we have concluded that in vitro culture is currently the most accurate diagnostic technique for determining infection prevalence of Ichthyophonus, particularly when the exposure history of the population is not known.

  13. [Diagnostic testing in fragile X syndrome].

    PubMed

    Sireteanu, Adriana; Rusu, Cristina

    2006-01-01

    Fragile X syndrome is the most common inherited cause of mental retardation. It is caused by a progressive expansion of polymeric (CGG)n trinucleotide repeats located on the FMR1 gene at Xq27.3. The spectrum of clinical involvement is broad, clinical diagnosis being difficult especially in young children. Hence, all cases of mental retardation without obvious cause should be tested for fragile X syndrome; the relatives of such a case need to be offered genetic counseling. Cytogenetic and molecular diagnostic tests are available. Recently, an immunocytochemical test has been described to identify fragile X patients, based on detection of FMR1 protein in cells using a monoclonal antibody. This method is used for screening, PCR based tests and Southern blot hybridization being the diagnostic tests for mutation and pre-mutation detection. Prenatal diagnosis is possible.

  14. Diagnostic self-testing: autonomous choices and relational responsibilities.

    PubMed

    Kearns, Alan J; O'Mathúna, Dónal P; Scott, P Anne

    2010-05-01

    Diagnostic self-testing devices are being developed for many illnesses, chronic diseases and infections. These will be used in hospitals, at point-of-care facilities and at home. Designed to allow earlier detection of diseases, self-testing diagnostic devices may improve disease prevention, slow the progression of disease and facilitate better treatment outcomes. These devices have the potential to benefit both the individual and society by enabling individuals to take a more proactive role in the maintenance of their health and by helping society improve health and reduce health costs. However, the full implications of future home-based diagnostic technology for individuals and society remain unclear due to their novelty. We argue that the development of diagnostic tools, especially for home use, will heighten a number of ethical challenges. This paper will explore some of the ethical implications of home-based self-testing diagnostic devices for the autonomous and relational dimensions of the person. This will be facilitated by examining the impact of diagnostic devices for individual autonomy, for the delivery of accurate diagnosis and for the personal significance of the information for the user. The latter will be examined using Charles Taylor's view of personhood and his emphasis on human agency and interpretation. While the ethical issues are not necessarily new, the development of home-based self-testing diagnostic devices will make issues regarding autonomy, accuracy of information and personal significance more and more demanding. This will be the case particularly when an individual's autonomous choices come into conflict with the person's relational responsibilities.

  15. 9 CFR 93.406 - Diagnostic tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Diagnostic tests. 93.406 Section 93.406 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN...

  16. Computerized Diagnostic Testing: Problems and Possibilities.

    ERIC Educational Resources Information Center

    McArthur, David L.

    The use of computers to build diagnostic inferences is explored in two contexts. In computerized monitoring of liquid oxygen systems for the space shuttle, diagnoses are exact because they can be derived within a world which is closed. In computerized classroom testing of reading comprehension, programs deliver a constrained form of adaptive…

  17. Detection sensitivity of influenza rapid diagnostic tests

    PubMed Central

    Sakai-Tagawa, Yuko; Ozawa, Makoto; Yamada, Shinya; Uchida, Yuko; Saito, Takehiko; Takahashi, Kazuo; Sugaya, Norio; Tashiro, Masato; Kawaoka, Yoshihiro

    2014-01-01

    We compared the sensitivity of influenza rapid diagnostic tests (IRDTs) currently available in Japan for various influenza virus strains, including human H7N9 and H5N1 isolates. We found that all of the IRDTs examined detected these viruses, but their detection sensitivities differed. PMID:25079880

  18. Diagnostic Tests in Reading: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Pupil Testing and Advisory Services.

    This publication lists and describes diagnostic reading tests available from United States publishers. Critical reviews by outside experts are included and supplemented by the compiler's comments. The external reviews are abstracted from "The Mental Measurements Yearbooks," edited by O. K. Buros, and cited by Yearbook edition and entry number. The…

  19. 42 CFR 410.33 - Independent diagnostic testing facility.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... performs a test he or she is authorized by the State to perform, or an independent diagnostic testing... furnishes diagnostic procedures in a physician's office. (2) Exceptions. The following diagnostic tests that... Drug Administration. (ii) Diagnostic tests personally furnished by a qualified audiologist as...

  20. 42 CFR 410.33 - Independent diagnostic testing facility.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... performs a test he or she is authorized by the State to perform, or an independent diagnostic testing... furnishes diagnostic procedures in a physician's office. (2) Exceptions. The following diagnostic tests that... Drug Administration. (ii) Diagnostic tests personally furnished by a qualified audiologist as...

  1. Update on Malaria Diagnostics and Test Utilization.

    PubMed

    Mathison, Blaine A; Pritt, Bobbi S

    2017-04-12

    Malaria is a potentially life-threatening disease requiring rapid diagnosis and treatment. Although microscopic examination of thick and thin blood films remains the gold standard for laboratory diagnosis, rapid antigen tests and nucleic acid amplification methods may also play a useful role for detection of acute infection. This review discusses the advantages and disadvantages of the commonly-used diagnostic methods and provides important practice points for optimal malaria test utilization.

  2. Diagnostic methods for CW laser damage testing

    NASA Astrophysics Data System (ADS)

    Stewart, Alan F.; Shah, Rashmi S.

    2004-06-01

    High performance optical coatings are an enabling technology for many applications - navigation systems, telecom, fusion, advanced measurement systems of many types as well as directed energy weapons. The results of recent testing of superior optical coatings conducted at high flux levels will be presented. The diagnostics used in this type of nondestructive testing and the analysis of the data demonstrates the evolution of test methodology. Comparison of performance data under load to the predictions of thermal and optical models shows excellent agreement. These tests serve to anchor the models and validate the performance of the materials and coatings.

  3. Applied Studies in Computerized Diagnostic Testing: Implications for Practice. Diagnostic Testing Project.

    ERIC Educational Resources Information Center

    McArthur, David L.

    The use of computers to build diagnostic inferences is presented in two contexts: (1) closed world, exemplified by the space shuttle launch monitoring system; and (2) open world, represented by computerized diagnostic testing of reading comprehension. The analysis shows that the closed world provides a substantially cleaner environment within…

  4. Using Copula Distributions to Support More Accurate Imaging-Based Diagnostic Classifiers for Neuropsychiatric Disorders

    PubMed Central

    Bansal, Ravi; Hao, Xuejun; Liu, Jun; Peterson, Bradley S.

    2014-01-01

    Many investigators have tried to apply machine learning techniques to magnetic resonance images (MRIs) of the brain in order to diagnose neuropsychiatric disorders. Usually the number of brain imaging measures (such as measures of cortical thickness and measures of local surface morphology) derived from the MRIs (i.e., their dimensionality) has been large (e.g. >10) relative to the number of participants who provide the MRI data (<100). Sparse data in a high dimensional space increases the variability of the classification rules that machine learning algorithms generate, thereby limiting the validity, reproducibility, and generalizability of those classifiers. The accuracy and stability of the classifiers can improve significantly if the multivariate distributions of the imaging measures can be estimated accurately. To accurately estimate the multivariate distributions using sparse data, we propose to estimate first the univariate distributions of imaging data and then combine them using a Copula to generate more accurate estimates of their multivariate distributions. We then sample the estimated Copula distributions to generate dense sets of imaging measures and use those measures to train classifiers. We hypothesize that the dense sets of brain imaging measures will generate classifiers that are stable to variations in brain imaging measures, thereby improving the reproducibility, validity, and generalizability of diagnostic classification algorithms in imaging datasets from clinical populations. In our experiments, we used both computer-generated and real-world brain imaging datasets to assess the accuracy of multivariate Copula distributions in estimating the corresponding multivariate distributions of real-world imaging data. Our experiments showed that diagnostic classifiers generated using imaging measures sampled from the Copula were significantly more accurate and more reproducible than were the classifiers generated using either the real-world imaging

  5. Diagnostic yield of blood clot culture in the accurate diagnosis of enteric fever and human brucellosis.

    PubMed

    Mantur, Basappa G; Bidari, Laxman H; Akki, Aravind S; Mulimani, Mallanna S; Tikare, Nitin V

    2007-01-01

    Culture of blood is the most frequent, accurate means of diagnosing bacteremia in enteric fever and brucellosis. However, conventional blood culturing is slow in isolating bacteria causing these diseases. In this work, we evaluated the performance of blood clot culture and conventional whole blood cultures in the accurate diagnosis of enteric fever (253 cases) and human brucellosis (71cases). The blood clot culture was found to be much more sensitive for both Salmonella (more by 34.4%, P< 0.001) and Brucella (more by 22.6%, P<0.001) than whole blood culture. Bacterial growth was significantly faster in cultures of blood clot compared to whole blood (1.1 versus 2.6 days for Salmonella, 3.1 versus 8.2 days for Brucella melitensis, respectively). The rapid confirmation of the etiological agent would facilitate an early institution of appropriate antimicrobial therapy, thereby reducing clinical morbidity especially in an endemic population. It is worthwile practicing blood clot culture for the accurate diagnosis of enteric fever and brucellosis in developing countries where diagnostic facilities by advanced technologies like automated culture systems and PCR are not available.

  6. Immunochromatographic diagnostic test analysis using Google Glass.

    PubMed

    Feng, Steve; Caire, Romain; Cortazar, Bingen; Turan, Mehmet; Wong, Andrew; Ozcan, Aydogan

    2014-03-25

    We demonstrate a Google Glass-based rapid diagnostic test (RDT) reader platform capable of qualitative and quantitative measurements of various lateral flow immunochromatographic assays and similar biomedical diagnostics tests. Using a custom-written Glass application and without any external hardware attachments, one or more RDTs labeled with Quick Response (QR) code identifiers are simultaneously imaged using the built-in camera of the Google Glass that is based on a hands-free and voice-controlled interface and digitally transmitted to a server for digital processing. The acquired JPEG images are automatically processed to locate all the RDTs and, for each RDT, to produce a quantitative diagnostic result, which is returned to the Google Glass (i.e., the user) and also stored on a central server along with the RDT image, QR code, and other related information (e.g., demographic data). The same server also provides a dynamic spatiotemporal map and real-time statistics for uploaded RDT results accessible through Internet browsers. We tested this Google Glass-based diagnostic platform using qualitative (i.e., yes/no) human immunodeficiency virus (HIV) and quantitative prostate-specific antigen (PSA) tests. For the quantitative RDTs, we measured activated tests at various concentrations ranging from 0 to 200 ng/mL for free and total PSA. This wearable RDT reader platform running on Google Glass combines a hands-free sensing and image capture interface with powerful servers running our custom image processing codes, and it can be quite useful for real-time spatiotemporal tracking of various diseases and personal medical conditions, providing a valuable tool for epidemiology and mobile health.

  7. Biostatistics Series Module 7: The Statistics of Diagnostic Tests.

    PubMed

    Hazra, Avijit; Gogtay, Nithya

    2017-01-01

    Crucial therapeutic decisions are based on diagnostic tests. Therefore, it is important to evaluate such tests before adopting them for routine use. Although things such as blood tests, cultures, biopsies, and radiological imaging are obvious diagnostic tests, it is not to be forgotten that specific clinical examination procedures, scoring systems based on physiological or psychological evaluation, and ratings based on questionnaires are also diagnostic tests and therefore merit similar evaluation. In the simplest scenario, a diagnostic test will give either a positive (disease likely) or negative (disease unlikely) result. Ideally, all those with the disease should be classified by a test as positive and all those without the disease as negative. Unfortunately, practically no test gives 100% accurate results. Therefore, leaving aside the economic question, the performance of diagnostic tests is evaluated on the basis of certain indices such as sensitivity, specificity, positive predictive value, and negative predictive value. Likelihood ratios combine information on specificity and sensitivity to expresses the likelihood that a given test result would occur in a subject with a disorder compared to the probability that the same result would occur in a subject without the disorder. Not all test can be categorized simply as "positive" or "negative." Physicians are frequently exposed to test results on a numerical scale, and in such cases, judgment is required in choosing a cutoff point to distinguish normal from abnormal. Naturally, a cutoff value should provide the greatest predictive accuracy, but there is a trade-off between sensitivity and specificity here - if the cutoff is too low, it will identify most patients who have the disease (high sensitivity) but will also incorrectly identify many who do not (low specificity). A receiver operating characteristic curve plots pairs of sensitivity versus (1 - specificity) values and helps in selecting an optimum cutoff

  8. Biostatistics Series Module 7: The Statistics of Diagnostic Tests

    PubMed Central

    Hazra, Avijit; Gogtay, Nithya

    2017-01-01

    Crucial therapeutic decisions are based on diagnostic tests. Therefore, it is important to evaluate such tests before adopting them for routine use. Although things such as blood tests, cultures, biopsies, and radiological imaging are obvious diagnostic tests, it is not to be forgotten that specific clinical examination procedures, scoring systems based on physiological or psychological evaluation, and ratings based on questionnaires are also diagnostic tests and therefore merit similar evaluation. In the simplest scenario, a diagnostic test will give either a positive (disease likely) or negative (disease unlikely) result. Ideally, all those with the disease should be classified by a test as positive and all those without the disease as negative. Unfortunately, practically no test gives 100% accurate results. Therefore, leaving aside the economic question, the performance of diagnostic tests is evaluated on the basis of certain indices such as sensitivity, specificity, positive predictive value, and negative predictive value. Likelihood ratios combine information on specificity and sensitivity to expresses the likelihood that a given test result would occur in a subject with a disorder compared to the probability that the same result would occur in a subject without the disorder. Not all test can be categorized simply as “positive” or “negative.” Physicians are frequently exposed to test results on a numerical scale, and in such cases, judgment is required in choosing a cutoff point to distinguish normal from abnormal. Naturally, a cutoff value should provide the greatest predictive accuracy, but there is a trade-off between sensitivity and specificity here - if the cutoff is too low, it will identify most patients who have the disease (high sensitivity) but will also incorrectly identify many who do not (low specificity). A receiver operating characteristic curve plots pairs of sensitivity versus (1 − specificity) values and helps in selecting an

  9. [Genetic diagnostic testing in inherited retinal dystrophies].

    PubMed

    Kohl, S; Biskup, S

    2013-03-01

    Inherited retinal dystrophies are clinically and genetically highly heterogeneous. They can be divided according to the clinical phenotype and course of the disease, as well as the underlying mode of inheritance. Isolated retinal dystrophies (i.e., retinitis pigmentosa, Leber's congenital amaurosis, cone and cone-rod dystrophy, macular dystrophy, achromatopsia, congenital stationary nightblindness) and syndromal forms (i.e., Usher syndrome, Bardet-Biedl syndrome) can be differentiated. To date almost 180 genes and thousands of distinct mutations have been identified that are responsible for the different forms of these blinding illnesses. Until recently, there was no adequate diagnostic genetic testing available. With the development of the next generation sequencing technologies, a comprehensive genetic screening analysis for all known genes for inherited retinal dystrophies has been established at reasonable costs and in appropriate turn-around times. Depending on the primary clinical diagnosis and the presumed mode of inheritance, different diagnostic panels can be chosen for genetic testing. Statistics show that in 55-80 % of the cases the genetic defect of the inherited retinal dystrophy can be identified with this approach, depending on the initial clinical diagnosis. The aim of any genetic diagnostics is to define the genetic cause of a given illness within the affected patient and family and thereby i) confirm the clinical diagnosis, ii) provide targeted genetic testing in family members, iii) enable therapeutic intervention, iv) give a prognosis on disease course and progression and v) in the long run provide the basis for novel therapeutic approaches and personalised medicine.

  10. Google glass based immunochromatographic diagnostic test analysis

    NASA Astrophysics Data System (ADS)

    Feng, Steve; Caire, Romain; Cortazar, Bingen; Turan, Mehmet; Wong, Andrew; Ozcan, Aydogan

    2015-03-01

    Integration of optical imagers and sensors into recently emerging wearable computational devices allows for simpler and more intuitive methods of integrating biomedical imaging and medical diagnostics tasks into existing infrastructures. Here we demonstrate the ability of one such device, the Google Glass, to perform qualitative and quantitative analysis of immunochromatographic rapid diagnostic tests (RDTs) using a voice-commandable hands-free software-only interface, as an alternative to larger and more bulky desktop or handheld units. Using the built-in camera of Glass to image one or more RDTs (labeled with Quick Response (QR) codes), our Glass software application uploads the captured image and related information (e.g., user name, GPS, etc.) to our servers for remote analysis and storage. After digital analysis of the RDT images, the results are transmitted back to the originating Glass device, and made available through a website in geospatial and tabular representations. We tested this system on qualitative human immunodeficiency virus (HIV) and quantitative prostate-specific antigen (PSA) RDTs. For qualitative HIV tests, we demonstrate successful detection and labeling (i.e., yes/no decisions) for up to 6-fold dilution of HIV samples. For quantitative measurements, we activated and imaged PSA concentrations ranging from 0 to 200 ng/mL and generated calibration curves relating the RDT line intensity values to PSA concentration. By providing automated digitization of both qualitative and quantitative test results, this wearable colorimetric diagnostic test reader platform on Google Glass can reduce operator errors caused by poor training, provide real-time spatiotemporal mapping of test results, and assist with remote monitoring of various biomedical conditions.

  11. Accuracy of diagnostic testing in primary ciliary dyskinesia

    PubMed Central

    Jackson, Claire L.; Behan, Laura; Goggin, Patricia M.; Adam, Elizabeth C.; Coles, Janice L.; Evans, Hazel J.; Harris, Amanda; Lackie, Peter; Packham, Samantha; Page, Anton; Thompson, James; Walker, Woolf T.; Kuehni, Claudia

    2016-01-01

    Diagnosis of primary ciliary dyskinesia (PCD) lacks a “gold standard” test and is therefore based on combinations of tests including nasal nitric oxide (nNO), high-speed video microscopy analysis (HSVMA), genotyping and transmission electron microscopy (TEM). There are few published data on the accuracy of this approach. Using prospectively collected data from 654 consecutive patients referred for PCD diagnostics we calculated sensitivity and specificity for individual and combination testing strategies. Not all patients underwent all tests. HSVMA had excellent sensitivity and specificity (100% and 93%, respectively). TEM was 100% specific, but 21% of PCD patients had normal ultrastructure. nNO (30 nL·min−1 cut-off) had good sensitivity and specificity (91% and 96%, respectively). Simultaneous testing using HSVMA and TEM was 100% sensitive and 92% specific. In conclusion, combination testing was found to be a highly accurate approach for diagnosing PCD. HSVMA alone has excellent accuracy, but requires significant expertise, and repeated sampling or cell culture is often needed. TEM alone is specific but misses 21% of cases. nNO (≤30 nL·min−1) contributes well to the diagnostic process. In isolation nNO screening at this cut-off would miss ∼10% of cases, but in combination with HSVMA could reduce unnecessary further testing. Standardisation of testing between centres is a future priority. PMID:26647444

  12. Bioaccessibility tests accurately estimate bioavailability of lead to quail

    USGS Publications Warehouse

    Beyer, W. Nelson; Basta, Nicholas T; Chaney, Rufus L.; Henry, Paula F.; Mosby, David; Rattner, Barnett A.; Scheckel, Kirk G.; Sprague, Dan; Weber, John

    2016-01-01

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from five Pb-contaminated Superfund sites had relative bioavailabilities from 33%-63%, with a mean of about 50%. Treatment of two of the soils with phosphorus significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in six in vitro tests and regressed on bioavailability. They were: the “Relative Bioavailability Leaching Procedure” (RBALP) at pH 1.5, the same test conducted at pH 2.5, the “Ohio State University In vitro Gastrointestinal” method (OSU IVG), the “Urban Soil Bioaccessible Lead Test”, the modified “Physiologically Based Extraction Test” and the “Waterfowl Physiologically Based Extraction Test.” All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the RBALP pH 2.5 and OSU IVG tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite and tertiary Pb phosphate), and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb.

  13. Bioaccessibility tests accurately estimate bioavailability of lead to quail.

    PubMed

    Beyer, W Nelson; Basta, Nicholas T; Chaney, Rufus L; Henry, Paula F P; Mosby, David E; Rattner, Barnett A; Scheckel, Kirk G; Sprague, Daniel T; Weber, John S

    2016-09-01

    Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in 6 in vitro tests and regressed on bioavailability: the relative bioavailability leaching procedure at pH 1.5, the same test conducted at pH 2.5, the Ohio State University in vitro gastrointestinal method, the urban soil bioaccessible lead test, the modified physiologically based extraction test, and the waterfowl physiologically based extraction test. All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the relative bioavailability leaching procedure at pH 2.5 and Ohio State University in vitro gastrointestinal tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite, and tertiary Pb phosphate) and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb, and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb. Environ Toxicol Chem 2016;35:2311-2319. Published 2016 Wiley Periodicals Inc. on behalf of

  14. A New Diagnostic Test for Endometrial Cancer?

    PubMed Central

    Guralp, Onur; Sheridan, Susan M.; Harter, Josephine; Hinshaw, James Louis; Seo, Songwon; Hartenbach, Ellen M.; Lindheim, Steven; Stewar, Sarah; Kushner, David M.

    2014-01-01

    Objective During saline-infused sonohysterography (SIS), the distension fluid is typically discarded. If cytology analysis could identify those patients with endometrial cancer, many women would be spared from further procedures. Methods Thirty consecutive patients with clinical stage I or II endometrial adenocarcinoma were prospectively recruited preoperatively. Saline-infused sonohysterography was performed by instilling 5 mL of saline, withdrawing and sending for analysis. Saline was reinfused until complete SIS images were obtained and sent separately for cytology. Results Of the 30 women enrolled, SIS was technically successful in 29. Demographics included mean age (60.5 ± 6.99 years), body mass index (35.55 ± 8.18 kg/m2), endometrioid histology (76%), and grade (grade 1, 67%). Prestudy diagnostic method included biopsy (70%), dilatation and curettage (17%), and hysteroscopy (10%). Adequate cytology specimens were obtained in 66% of the 5mL flushes and 72% of the complete SIS collections. Of adequate specimens, the sensitivities to detect endometrial cancer for the 5-mL, complete, and combined fluid samples were 26% (95% confidence interval, 9%–51%), 36% (17%–59%), and 42% (22%–63%). Sensitivity based on the whole study sample (N = 30) was 33% (17%–53%). Statistical significance was not found in the association between a positive test and age, body mass index, grade, diagnostic method, or volume instilled or aspirated. Conclusions Most patients with early endometrial cancer can undergo SIS procedures with adequate cytology specimens obtained from distention media. However, the sensitivity is low, and refinements are necessary before utilizing as a diagnostic test. In cases with positive results, the patient may be able to avoid other costly and painful procedures. PMID:23881100

  15. Clonality Testing in Veterinary Medicine: A Review With Diagnostic Guidelines.

    PubMed

    Keller, S M; Vernau, W; Moore, P F

    2016-07-01

    The accurate distinction of reactive and neoplastic lymphoid proliferations can present challenges. Given the different prognoses and treatment strategies, a correct diagnosis is crucial. Molecular clonality assays assess rearranged lymphocyte antigen receptor gene diversity and can help differentiate reactive from neoplastic lymphoid proliferations. Molecular clonality assays are commonly used to assess atypical, mixed, or mature lymphoid proliferations; small tissue fragments that lack architecture; and fluid samples. In addition, clonality testing can be utilized to track neoplastic clones over time or across anatomic sites. Molecular clonality assays are not stand-alone tests but useful adjuncts that follow clinical, morphologic, and immunophenotypic assessment. Even though clonality testing provides valuable information in a variety of situations, the complexities and pitfalls of this method, as well as its dependency on the experience of the interpreter, are often understated. In addition, a lack of standardized terminology, laboratory practices, and interpretational guidelines hinders the reproducibility of clonality testing across laboratories in veterinary medicine. The objectives of this review are twofold. First, the review is intended to familiarize the diagnostic pathologist or interested clinician with the concepts, potential pitfalls, and limitations of clonality testing. Second, the review strives to provide a basis for future harmonization of clonality testing in veterinary medicine by providing diagnostic guidelines.

  16. Development of the Astronomy Diagnostic Test

    NASA Astrophysics Data System (ADS)

    Hufnagel, B.

    2001-12-01

    The starting point for questions in the Astronomy Diagnostic Test (ADT) Version 2.0 was two precursor surveys, the STAR Evaluation by Philip M. Sadler and Michael Zeilik's Astronomy Diagnostic Test Version 1.0. Questions were selected or developed for the new ADT which (1) addressed concepts included in most introductory astronomy courses for non-science majors, (2) included only concepts recognizable to most high-school graduates, (3) focused on one concept only, and (4) stressed concepts and not jargon. This version was administered to about 1000 students at four colleges and universities. The statistical results, e.g., item discrimination, guided re-writing and elimination of questions. Sixty student interviews at Montana State and the University of Maryland, as well as thirty written responses to the questions in open-ended format, were the basis for determining if the questions were interpreted by the students as intended. This student input was also the basis for distractors (wrong answers) reflecting the ideas and the words of the students themselves. After revision, the ADT was administered the next semester to 1557 students enrolled in 22 introductory classes, twenty students were interviewed, and comments solicited from the instructors of those classes. The result was the final ADT Version 2.0, which consists of 21 content and 12 student background multiple-choice questions. This work has been partly supported by NSF grant # DGE-9714489.

  17. Diagnostic testing managed by hematopathology specialty and other laboratories: costs and patient diagnostic outcomes

    PubMed Central

    2014-01-01

    Background Successful management of patients with hematologic malignancies depends upon accurate and timely diagnosis, which frequently requires integration and interpretation of multiple tests. Our retrospective analysis compared diagnostic uncertainty, resource utilization, and costs for patients with diagnostic bone marrow (BM) tests managed by commercial laboratories. Methods Patients with BM biopsies and suspected hematologic cancer/condition were identified from claims (2005–2011) within a large US health plan (coverage ≥6 pre- and ≥3-months post-biopsy). Cohorts defined by laboratories performing BM morphologic assessment/directing testing sequence: Genoptix (GX, specialty hematology-testing laboratory), large commercial laboratories (LL), other laboratories (OL). One-year post-biopsy changes in diagnosis or treatments, tests performed, and diagnostic/treatment medical costs (measured as per-patient-per-month [PPPM]) were examined. Results The study population included 1,387 GX, 4,162 LL, and 19,115 OL patients with suspected hematologic malignancy/disease and BM morphology assessment. GX had lower diagnostic uncertainty measured between 2 time periods by diagnostic stability (no conditions the same; 6.16% GX, 8.04% LL, 9.73% OL; p < 0.001) and changes (≥1 condition different; 7.88% GX, 11.19% LL, and 14.08% OL; p < 0.001), fewer repeat BM biopsies, and fewer chemotherapy changes (30-days and 60-days post-initiation). One-year PPPM costs adjusted for patient characteristics differences were $8,202 GX, $7,711 LL, and $10,302 OL (p < 0.05); adjusted PPPM costs (excluding testing period) were $6,019 GX, $6,649 LL, and $7,801 OL (p < 0.05). Conclusions Our data suggests that a hematopathology specialty laboratory may result in earlier final diagnosis, fewer subsequent diagnosis changes, reduced need for follow-on testing requiring repeat biopsy procedures, and may result in lower downstream healthcare costs. Further evaluations using

  18. Evaluation of a pan-serotype point-of-care rapid diagnostic assay for accurate detection of acute dengue infection.

    PubMed

    Vivek, Rosario; Ahamed, Syed Fazil; Kotabagi, Shalini; Chandele, Anmol; Khanna, Ira; Khanna, Navin; Nayak, Kaustuv; Dias, Mary; Kaja, Murali-Krishna; Shet, Anita

    2017-03-01

    The catastrophic rise in dengue infections in India and globally has created a need for an accurate, validated low-cost rapid diagnostic test (RDT) for dengue. We prospectively evaluated the diagnostic performance of NS1/IgM RDT (dengue day 1) using 211 samples from a pediatric dengue cohort representing all 4 serotypes in southern India. The dengue-positive panel consisted of 179 dengue real-time polymerase chain reaction (RT-PCR) positive samples from symptomatic children. The dengue-negative panel consisted of 32 samples from dengue-negative febrile children and asymptomatic individuals that were negative for dengue RT-PCR/NS1 enzyme-linked immunosorbent assay/IgM/IgG. NS1/IgM RDT sensitivity was 89.4% and specificity was 93.8%. The NS1/IgM RDT showed high sensitivity throughout the acute phase of illness, in primary and secondary infections, in different severity groups, and detected all 4 dengue serotypes, including coinfections. This NS1/IgM RDT is a useful point-of-care assay for rapid and reliable diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.

  19. Double-shearing interferometer for accurate test of laser wavefront

    NASA Astrophysics Data System (ADS)

    Luan, Zhu; Liu, Liren; Zu, Jifeng; Teng, Shuyun

    2004-01-01

    Inter-satellite laser communications require nearly diffraction-limited laser beam, correspondingly an accurate test of laser wavefront is necessary. In this paper, an aperture-divided double lateral-shearing interferometer is developed which can be used for wavefront analysis ranged nearly from 0.1λ to λ with a simple structure and no alignment needed. The interferometer includes two Jamin plane parallel plates and four slightly wedge-shaped plates of the same size. The four wedged plates are combined into two pairs of different wedges, which are separately placed in the arms of the Jamin interferometer. The thickness of a plate leads to a beam shift, and the wedge a beam inclination, so that there appears two shearing interferogram of different background fringes in a divided aperture. Plane wavefront, perfect spherical wavefront and some types of aberration including primary spherical aberration, primary coma are simulated. It is concluded that the measurable wavefront height of laser beam reaches to better than 0.1λ. Note that the interference is from the beams of equal optical distance thus suitable for semiconductor lasers for the space application, which may be with the coherent length of millimeters.

  20. New challenges for BRCA testing: a view from the diagnostic laboratory

    PubMed Central

    Wallace, Andrew J

    2016-01-01

    Increased demand for BRCA testing is placing pressures on diagnostic laboratories to raise their mutation screening capacity and handle the challenges associated with classifying BRCA sequence variants for clinical significance, for example interpretation of pathogenic mutations or variants of unknown significance, accurate determination of large genomic rearrangements and detection of somatic mutations in DNA extracted from formalin-fixed, paraffin-embedded tumour samples. Many diagnostic laboratories are adopting next-generation sequencing (NGS) technology to increase their screening capacity and reduce processing time and unit costs. However, migration to NGS introduces complexities arising from choice of components of the BRCA testing workflow, such as NGS platform, enrichment method and bioinformatics analysis process. An efficient, cost-effective accurate mutation detection strategy and a standardised, systematic approach to the reporting of BRCA test results is imperative for diagnostic laboratories. This review covers the challenges of BRCA testing from the perspective of a diagnostics laboratory. PMID:27514839

  1. [Critical reading of articles about diagnostic tests (part II): Analyzing results].

    PubMed

    Moratalla Rodríguez, G

    2015-01-01

    A new diagnostic test needs to be validated through comparison with a reference standard in an appropriate spectrum of patients. Diagnostic tests are not perfectly accurate; on the contrary, there can be false-positive and false-negative findings. A good diagnostic test is that which provides an acceptable proportion of positive results when a determinate condition is present in patients and an acceptable proportion of negative results when it is absent. The best measure of the usefulness of a diagnostic test is the likelihood ratio, which informs us to what degree a particular result is more likely in a person in whom a condition is present than in a person in whom the condition is absent. The present article discusses the fundamental statistical concepts necessary to interpret the results section of an article about a diagnostic test; however, the approach is clearly oriented toward clinical practice, with emphasis on concepts rather than mathematics.

  2. An overview of systematic reviews of diagnostic tests accuracy.

    PubMed

    Bae, Jong-Myon

    2014-01-01

    The Cochrane Collaboration says that the Cochrane handbook for diagnostic test accuracy reviews (DTAR) is currently in development as per the Cochrane Collaboration. This implies that the methodology of systematic reviews (SR) of diagnostic test accuracy is still a matter of debate. At this point, comparison of methodologies for SR in case of interventions as against diagnostics would be helpful to understand DTAR.

  3. 40 CFR 85.2207 - Onboard diagnostic test standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Tests § 85.2207 Onboard diagnostic test standards. (a) A vehicle shall fail the OBD test if it is a 1996... inoperable. (b) A vehicle shall fail the OBD test if the malfunction indicator light (MIL) is commanded to be... OBD test if the MIL is commanded to be illuminated for one or more diagnostic trouble codes (DTCs),...

  4. Blood-Mimicking Fluid for Testing Ultrasonic Diagnostic Instrument

    NASA Astrophysics Data System (ADS)

    Tanaka, Kouhei; Yoshida, Tomoji; Sato, Kazuishi; Kondo, Toshio; Yasukawa, Kazuhiro; Miyamoto, Nobuaki; Taniguchi, Masahiko

    2012-07-01

    We present a blood-mimicking fluid (BMF) for the Doppler test object of medical diagnostic instruments. Accurate measurement in a flow Doppler test requires a BMF that has the acoustic velocity and density defined in the International Electrotechnical Commission (IEC) standard, and furthermore, they must be stable over time. To formulate a fluid with the desired density and acoustic velocity, we have developed a new fluid made of glycerine and water-soluble silicone oil. The new BMF includes dispersed polystyrene particles as scatterers. The density of the liquid can be adjusted to maintain it at the same value as that of the polystyrene particles, thus ensuring neutral buoyancy of the particles. The MBF was stable over a period of 2 weeks, during which the density and acoustic velocity did not change.

  5. SSME Post Test Diagnostic System: Systems Section

    NASA Technical Reports Server (NTRS)

    Bickmore, Timothy

    1995-01-01

    An assessment of engine and component health is routinely made after each test firing or flight firing of a Space Shuttle Main Engine (SSME). Currently, this health assessment is done by teams of engineers who manually review sensor data, performance data, and engine and component operating histories. Based on review of information from these various sources, an evaluation is made as to the health of each component of the SSME and the preparedness of the engine for another test or flight. The objective of this project - the SSME Post Test Diagnostic System (PTDS) - is to develop a computer program which automates the analysis of test data from the SSME in order to detect and diagnose anomalies. This report primarily covers work on the Systems Section of the PTDS, which automates the analyses performed by the systems/performance group at the Propulsion Branch of NASA Marshall Space Flight Center (MSFC). This group is responsible for assessing the overall health and performance of the engine, and detecting and diagnosing anomalies which involve multiple components (other groups are responsible for analyzing the behavior of specific components). The PTDS utilizes several advanced software technologies to perform its analyses. Raw test data is analyzed using signal processing routines which detect features in the data, such as spikes, shifts, peaks, and drifts. Component analyses are performed by expert systems, which use 'rules-of-thumb' obtained from interviews with the MSFC data analysts to detect and diagnose anomalies. The systems analysis is performed using case-based reasoning. Results of all analyses are stored in a relational database and displayed via an X-window-based graphical user interface which provides ranked lists of anomalies and observations by engine component, along with supporting data plots for each.

  6. BIOACCESSIBILITY TESTS ACCURATELY ESTIMATE BIOAVAILABILITY OF LEAD TO QUAIL

    EPA Science Inventory

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contami...

  7. Bioaccessibility tests accurately estimate bioavailability of lead to quail

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb, we incorporated Pb-contaminated soils or Pb acetate into diets for Japanese quail (Coturnix japonica), fed the quail for 15 days, and ...

  8. RT-PCR is a more accurate diagnostic tool for detection of BCR-ABL rearrangement

    SciTech Connect

    Zehnbauer, B.A.; Allen, A.P.; McGrath, S.D.

    1994-09-01

    Detection of the Philadelphia chromosome (Ph1) or genomic Southern hybridization for clonal gene rearrangement (GSH-R) has provided very specific identification of BCR-ABL gene rearrangement. Reverse transcriptase-polymerase chain reaction (RT-PCR) is diagnostic for patterns of BCR-ABL expression which are undetected by GSH-R and/or Ph1 and provides increased sensitivity both at diagnosis and in detection of minimal residual leukemia. Fifty-three specimens (of 150 tested from 119 consecutive leukemia patients) were RT-PCR positive for BCR-ABL gene expression confirmed by hybridization of PCR products with b{sub 3}a{sub 2}, b{sub 2}a{sub 2}, or e{sub 1}a{sub 2} junction-specific oligonucleotides. In 6 cases of CML with GSH-R{sup {minus}}at diagnosis, RT-PCR provided specific BCR-ABL identification. Deletion of BCR regions, low mitotic index, or e{sub 1}a{sub 2} expression caused failure to detect GSH-R or Ph1 translocation.

  9. Diagnostic Testing and the Development of CAL Remedial Sequences.

    ERIC Educational Resources Information Center

    Ferraris, M.; And Others

    1984-01-01

    Presents methodology for designing and delivering computer-assisted diagnostic tests and discusses two natural applications of this methodology: for testing purposes, and for implementing adaptive computer-assisted learning sequences based on test results. (MBR)

  10. Computer-aided selection of diagnostic tests in jaundiced patients.

    PubMed Central

    Saint-Marc Girardin, M F; Le Minor, M; Alperovitch, A; Roudot-Thoraval, F; Metreau, J M; Dhumeaux, D

    1985-01-01

    A model has been developed for ordering diagnostic tests in jaundiced patients. The system proceeds in two steps: (i) diagnostic hypotheses are calculated for each patient from the results of physical examination and routine biological investigations; (ii) given these hypotheses, the most efficient test (out of 22) for reaching the final diagnosis is selected using four criteria: diagnostic value, risk, financial cost, and time in obtaining the result. This model was tested in 62 patients. In 43 of them (69%), the selected test was sufficient for reaching a diagnostic accuracy of 100%. In this group of patients, a mean of 3.7 (range 1-6) tests per patient was ordered by physicians. In the 19 remaining patients, the selected test was not sufficient for the final diagnosis, thus requiring a multiple choice process. It is suggested that such a system could help physicians to improve the care of patients by more efficient ordering of diagnostic tests. PMID:3896962

  11. The glucose breath test: a diagnostic test for small bowel stricture(s) in Crohn's disease.

    PubMed

    Mishkin, Daniel; Boston, Francis M; Blank, David; Yalovsky, Morty; Mishkin, Seymour

    2002-03-01

    The aim of this study was to determine whether an indirect noninvasive indicator of proximal bacterial overgrowth, the glucose breath test, was of diagnostic value in inflammatory bowel disease. Twenty four of 71 Crohn's disease patients tested had a positive glucose breath test. No statistical conclusions could be drawn between the Crohn's disease activity index and glucose breath test status. Of patients with radiologic evidence of small bowel stricture(s), 96.0% had a positive glucose breath test, while only one of 46 negative glucose breath test patients had a stricture. The positive and negative predictive values for a positive glucose breath test as an indicator of stricture formation were 96.0% and 97.8%, respectively. This correlation was not altered in Crohn's disease patients with fistulae or status postresection of the terminal ileum. The data in ulcerative colitis were nondiagnostic. In conclusion, the glucose breath test appears to be an accurate noninvasive inexpensive diagnostic test for small bowel stricture(s) and secondary bacterial overgrowth in Crohn's disease.

  12. Diagnostic value of exercise testing in asbestosis

    SciTech Connect

    Zejda, J. )

    1989-01-01

    The diagnostic value of simple exercise testing was examined in 81 current male asbestos-cement workers, divided into four groups according to the International Labour Office (ILO) category of irregular opacities: 0/0, 25; 1/1, 24; 1/2, 22; and 2/2, 10 men. An increasing X-ray score was accompanied by more severe functional abnormality in keeping with the development of a restrictive defect. Symptom-limited oxygen uptake (VO2SL) did not depend on the X-ray grade and was 76.7, 71.9, 68.7, and 73.5% pv, respectively, for the four groups. Subjects with ILO score 1/1 had significantly higher exercise ventilation at O2 uptake of 1.01.min-1 (VE 1.0) than those with grade 0/0. End-exercise tidal volume (VTSL in 1) decreased with an increasing X-ray score: 2.14, 1.98, 1.85, and 1.62, respectively. VTSL standardized for vital capacity (VTSL/VC) followed the same pattern. Asbestosis was diagnosed in 25 men, in whom VE 1.0 was significantly higher (p less than .02) and VTSL lower (p less than .01) than in the 0/0 group. VO2SL was similar in both groups. The findings suggest that VE 1.0 and VTSL may be early functional indicators of asbestos-related interstitial lung fibrosis. The measurement of both exercise indices may increase the certainty of clinical diagnosis of asbestosis in subjects with less advanced disease.

  13. Beyond skin testing: state of the art and new horizons in food allergy diagnostic testing.

    PubMed

    Caubet, Jean-Christoph; Sampson, Hugh A

    2012-02-01

    Food allergy affects approximately 1% to 10.8% of the general population, and its prevalence seems to be increasing. An accurate diagnosis is particularly important because a misdiagnosis could lead to life-threatening reactions or to unnecessary restrictive diets. However, allergy tests currently used in clinical practice have limited accuracy, and an oral food challenge, considered as the gold standard, is often required to confirm or exclude a food allergy. This article reviews several promising novel approaches for the diagnosis of food allergy, such as new molecular diagnostic technologies and functional assays, along with their potential clinical applications.

  14. Diagnostic Testing at UK Universities: An E-Mail Survey

    ERIC Educational Resources Information Center

    Gillard, Jonathan; Levi, Margaret; Wilson, Robert

    2010-01-01

    In July 2009, an e-mail survey was sent to various UK universities to gain information regarding current practices concerning mathematics diagnostic testing, and to provide an update from the review "Diagnostic Testing for Mathematics" published by the LTSN MathsTEAM Project in 2003. A total of 38 university departments were contacted…

  15. 42 CFR 410.33 - Independent diagnostic testing facility.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) The physical facility, including mobile units, must contain space for equipment appropriate to the... 42 Public Health 2 2010-10-01 2010-10-01 false Independent diagnostic testing facility. 410.33... § 410.33 Independent diagnostic testing facility. (a) General rule. (1) Effective for...

  16. Assessing Diagnostic Tests II: Grading on a Curve.

    PubMed

    Jupiter, Daniel C

    2015-01-01

    In this Investigators' Corner, I continue discussing how to introduce and assess new diagnostic tests to replace older tests that are considered gold standards. Specifically, I talk about how to assess a "family" of diagnostics, and how to choose an optimal "family member."

  17. Clinical diagnostic gene expression thyroid testing.

    PubMed

    Steward, David L; Kloos, Richard T

    2014-08-01

    Thyroid fine-needle aspiration biopsies are cytologically indeterminate in 15% to 30% of cases. When cytologically indeterminate thyroid nodules undergo diagnostic surgery, approximately three-quarters prove to be histologically benign. A negative predictive value of more than or equal to 94% for the Afirma Gene Expression Classifier (GEC) is achieved for indeterminate nodules. Most Afirma GEC benign nodules can be clinically observed, as suggested by the National Comprehensive Cancer Network Thyroid Carcinoma Guideline. More than half of the benign nodules with indeterminate cytology (Bethesda categories III/IV) can be identified as GEC benign and removed from the surgical pool to prevent unnecessary diagnostic surgery.

  18. Upgrading Engine Test Cells for Improved Troubleshooting and Diagnostics

    DTIC Science & Technology

    2002-01-01

    being developed. To enable this, test cell fault detection and isolation capabilities will need to utilize all of the relevant engine and test...improved engine fault detection and isolation capabilities, various approaches for automated sensor validation, performance diagnostics and

  19. PIC Reading and Spelling Diagnostic Test Form.

    ERIC Educational Resources Information Center

    Short, N. J.

    This diagnostic skills checklist enables the methods and materials specialists to note the reading and spelling skills the child has mastered, those skills which are weak or not developed, and those skills which are clearly beyond the child's capability of mastering because of insufficiently developed abilities at lower, prerequisite levels. Also…

  20. Imaging tests for accurate diagnosis of acute biliary pancreatitis.

    PubMed

    Şurlin, Valeriu; Săftoiu, Adrian; Dumitrescu, Daniela

    2014-11-28

    Gallstones represent the most frequent aetiology of acute pancreatitis in many statistics all over the world, estimated between 40%-60%. Accurate diagnosis of acute biliary pancreatitis (ABP) is of outmost importance because clearance of lithiasis [gallbladder and common bile duct (CBD)] rules out recurrences. Confirmation of biliary lithiasis is done by imaging. The sensitivity of the ultrasonography (US) in the detection of gallstones is over 95% in uncomplicated cases, but in ABP, sensitivity for gallstone detection is lower, being less than 80% due to the ileus and bowel distension. Sensitivity of transabdominal ultrasonography (TUS) for choledocolithiasis varies between 50%-80%, but the specificity is high, reaching 95%. Diameter of the bile duct may be orientative for diagnosis. Endoscopic ultrasonography (EUS) seems to be a more effective tool to diagnose ABP rather than endoscopic retrograde cholangiopancreatography (ERCP), which should be performed only for therapeutic purposes. As the sensitivity and specificity of computerized tomography are lower as compared to state-of-the-art magnetic resonance cholangiopancreatography (MRCP) or EUS, especially for small stones and small diameter of CBD, the later techniques are nowadays preferred for the evaluation of ABP patients. ERCP has the highest accuracy for the diagnosis of choledocholithiasis and is used as a reference standard in many studies, especially after sphincterotomy and balloon extraction of CBD stones. Laparoscopic ultrasonography is a useful tool for the intraoperative diagnosis of choledocholithiasis. Routine exploration of the CBD in cases of patients scheduled for cholecystectomy after an attack of ABP was not proven useful. A significant rate of the so-called idiopathic pancreatitis is actually caused by microlithiasis and/or biliary sludge. In conclusion, the general algorithm for CBD stone detection starts with anamnesis, serum biochemistry and then TUS, followed by EUS or MRCP. In the end

  1. Smartphone-Based Accurate Analysis of Retinal Vasculature towards Point-of-Care Diagnostics

    PubMed Central

    Xu, Xiayu; Ding, Wenxiang; Wang, Xuemin; Cao, Ruofan; Zhang, Maiye; Lv, Peilin; Xu, Feng

    2016-01-01

    Retinal vasculature analysis is important for the early diagnostics of various eye and systemic diseases, making it a potentially useful biomarker, especially for resource-limited regions and countries. Here we developed a smartphone-based retinal image analysis system for point-of-care diagnostics that is able to load a fundus image, segment retinal vessels, analyze individual vessel width, and store or uplink results. The proposed system was not only evaluated on widely used public databases and compared with the state-of-the-art methods, but also validated on clinical images directly acquired with a smartphone. An Android app is also developed to facilitate on-site application of the proposed methods. Both visual assessment and quantitative assessment showed that the proposed methods achieved comparable results to the state-of-the-art methods that require high-standard workstations. The proposed system holds great potential for the early diagnostics of various diseases, such as diabetic retinopathy, for resource-limited regions and countries. PMID:27698369

  2. Better tests, better care: improved diagnostics for infectious diseases.

    PubMed

    Caliendo, Angela M; Gilbert, David N; Ginocchio, Christine C; Hanson, Kimberly E; May, Larissa; Quinn, Thomas C; Tenover, Fred C; Alland, David; Blaschke, Anne J; Bonomo, Robert A; Carroll, Karen C; Ferraro, Mary Jane; Hirschhorn, Lisa R; Joseph, W Patrick; Karchmer, Tobi; MacIntyre, Ann T; Reller, L Barth; Jackson, Audrey F

    2013-12-01

    In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians.

  3. Better Tests, Better Care: Improved Diagnostics for Infectious Diseases

    PubMed Central

    Caliendo, Angela M.; Gilbert, David N.; Ginocchio, Christine C.; Hanson, Kimberly E.; May, Larissa; Quinn, Thomas C.; Tenover, Fred C.; Alland, David; Blaschke, Anne J.; Bonomo, Robert A.; Carroll, Karen C.; Ferraro, Mary Jane; Hirschhorn, Lisa R.; Joseph, W. Patrick; Karchmer, Tobi; MacIntyre, Ann T.; Reller, L. Barth; Jackson, Audrey F.

    2013-01-01

    In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians. PMID:24200831

  4. Myasthenia Gravis: Tests and Diagnostic Methods

    MedlinePlus

    ... in several ways, including the following: Anti-MuSK Antibody testing----a blood test for the remaining 15% ... confirm a clinical diagnosis of MG. Acetylcholine Receptor Antibody — a blood test for the abnormal antibodies can ...

  5. Personalized Medicine’s Bottleneck: Diagnostic Test Evidence and Reimbursement

    PubMed Central

    Cohen, Joshua P.; Felix, Abigail E.

    2014-01-01

    Background: Personalized medicine is gradually emerging as a transformative field. Thus far, seven co-developed drug-diagnostic combinations have been approved and several dozen post-hoc drug-diagnostic combinations (diagnostic approved after the drug). However, barriers remain, particularly with respect to reimbursement. Purpose, methods: This study analyzes barriers facing uptake of drug-diagnostic combinations. We examine Medicare reimbursement in the U.S. of 10 drug-diagnostic combinations on the basis of a formulary review and a survey. Findings: We found that payers reimburse all 10 drugs, but with variable and relatively high patient co-insurance, as well as imposition of formulary restrictions. Payer reimbursement of companion diagnostics is limited and highly variable. In addition, we found that the body of evidence on the clinical- and cost-effectiveness of therapeutics is thin and even less robust for diagnostics. Conclusions, discussion: The high cost of personalized therapeutics and dearth of evidence concerning the comparative clinical effectiveness of drug-diagnostic combinations appear to contribute to high patient cost sharing, imposition of formulary restrictions, and limited and variable reimbursement of companion diagnostics. Our findings point to the need to increase the evidence base supportive of establishing linkage between diagnostic testing and positive health outcomes. PMID:25563222

  6. Diagnostic Testing for Sexually Transmitted Infections

    MedlinePlus

    ... nucleic acid test (viral load or HIV DNA PCR) is performed to confirm a diagnosis. For infants ... nucleic acid test (viral load or HIV DNA PCR) is recommended. For more information, visit www.hivtest. ...

  7. A vibration monitoring acquisition and diagnostic system for helicopter drive train bench tests

    NASA Astrophysics Data System (ADS)

    Dousis, Dimitri A.

    An automated drive train test stand vibration monitoring system called VMADS has been developed by Bell Helicopter Textron, Inc., and has been installed at Bell's transmission bench test facility. VMADS provides the operator with warning and alarm indications for preselected degraded conditions, and acquires vibration data to be used by engineers to improve the diagnostics for better fault detection and fault isolation. VMADS is used as a test bed for new monitoring and diagnostic algorithm evaluation and validation, a necessary step to ensure development of accurate, reliable integrated health usage monitoring systems for the Bell rotorcraft fleet. This paper highlights the VMADS features for helicopter and tiltrotor aircraft drive train bench test monitoring and diagnostics and discusses supportive ongoing health and usage monitoring activities at BHTI, both military and commercial for enhanced safety and reduced maintenance costs. Bell is translating VMADS developed capability to airborne applications, while simultaneously enhancing the original VMADS capabilities.

  8. Concordance in diagnostic testing for respiratory pathogens of Bighorn Sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack ...

  9. Review of rapid diagnostic tests used by antimicrobial stewardship programs.

    PubMed

    Bauer, Karri A; Perez, Katherine K; Forrest, Graeme N; Goff, Debra A

    2014-10-15

    Rapid microbiologic tests provide opportunities for antimicrobial stewardship programs to improve antimicrobial use and clinical and economic outcomes. Standard techniques for identification of organisms require at least 48-72 hours for final results, compared with rapid diagnostic tests that provide final organism identification within hours of growth. Importantly, rapid microbiologic tests are considered "game changers" and represent a significant advancement in the management of infectious diseases. This review focuses on currently available rapid diagnostic tests and, importantly, the impact of rapid testing in combination with antimicrobial stewardship on patient outcomes.

  10. Test, Measurement, and Diagnostic Equipment (System Peculiar)

    DTIC Science & Technology

    2007-11-02

    Potential Fault Detection and Isolation Test 4 4.6 Standard Design Characteristics. .. . . . . . 5 4.7 TMDE Interface Tests . . . . . . . . .. . 6 4.8...within purchase description requirements. (3) Any di,crepancies between the TMDE and the "calibrated’ system. 4.5 Potential Fault Detection and Isolation Te

  11. Motor-operated valve testing and diagnostics

    SciTech Connect

    Kuehn, S.E.

    1994-01-01

    This article addresses changes in testing requirements for nuclear power plant pumps and valves to assess the operational readiness of these components. The topics of the article include an overview of the scope of the requirements, NRC generic guidance, GL 89-10 programs, test quality, motor current signature analysis, operating principles, safety and availability.

  12. 40 CFR 85.2222 - Onboard diagnostic test procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Tests § 85.2222 Onboard diagnostic test procedures. The test sequence for the OBD inspection shall consist of the following steps: (a) The OBD inspection shall be conducted with the key-on/engine running... Mode $01, PID $01 request in accordance with 40 CFR 86.1806 to determine the OBD evaluation status....

  13. 40 CFR 85.2231 - Onboard diagnostic test equipment requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Emission Control System Performance Warranty Short Tests § 85.2231 Onboard diagnostic test equipment requirements. (a) The test system interface to the vehicle shall include a plug that conforms to the requirements and specifications of 40...

  14. 4D laser camera for accurate patient positioning, collision avoidance, image fusion and adaptive approaches during diagnostic and therapeutic procedures.

    PubMed

    Brahme, Anders; Nyman, Peter; Skatt, Björn

    2008-05-01

    A four-dimensional (4D) laser camera (LC) has been developed for accurate patient imaging in diagnostic and therapeutic radiology. A complementary metal-oxide semiconductor camera images the intersection of a scanned fan shaped laser beam with the surface of the patient and allows real time recording of movements in a three-dimensional (3D) or four-dimensional (4D) format (3D +time). The LC system was first designed as an accurate patient setup tool during diagnostic and therapeutic applications but was found to be of much wider applicability as a general 4D photon "tag" for the surface of the patient in different clinical procedures. It is presently used as a 3D or 4D optical benchmark or tag for accurate delineation of the patient surface as demonstrated for patient auto setup, breathing and heart motion detection. Furthermore, its future potential applications in gating, adaptive therapy, 3D or 4D image fusion between most imaging modalities and image processing are discussed. It is shown that the LC system has a geometrical resolution of about 0, 1 mm and that the rigid body repositioning accuracy is about 0, 5 mm below 20 mm displacements, 1 mm below 40 mm and better than 2 mm at 70 mm. This indicates a slight need for repeated repositioning when the initial error is larger than about 50 mm. The positioning accuracy with standard patient setup procedures for prostate cancer at Karolinska was found to be about 5-6 mm when independently measured using the LC system. The system was found valuable for positron emission tomography-computed tomography (PET-CT) in vivo tumor and dose delivery imaging where it potentially may allow effective correction for breathing artifacts in 4D PET-CT and image fusion with lymph node atlases for accurate target volume definition in oncology. With a LC system in all imaging and radiation therapy rooms, auto setup during repeated diagnostic and therapeutic procedures may save around 5 min per session, increase accuracy and allow

  15. Comparison of the Minnesota Percepto-Diagnostic Test-Revised and Bender-Gestalt in Predicting Achievement.

    ERIC Educational Resources Information Center

    Fuller, Gerald B.; Vance, Booney

    1993-01-01

    Investigated whether Minnesota Percepto-Diagnostic Test-Revised (MPD-R) or Bender-Gestalt Test (BG) would more accurately predict achievement at first-, third-, and fifth-grade levels. Administered both tests to 84 children in counterbalanced order. Results indicated that MPD-R was better predictor of achievement than BG, especially at first- and…

  16. Diagnostic tests in allergy to green coffee.

    PubMed

    Osterman, K; Johansson, S G; Zetterström, O

    1985-07-01

    Twenty-two coffee roastery workers with work-related symptoms of various degree from the eyes, nose or bronchi were tested with partly purified water-soluble extract from dust of green coffee beans (GCB). Eighteen persons had a positive prick test, eight a positive bronchial provocation test and seven a positive nasal provocation test. Fourteen had a positive methacholine test, indicating unspecific bronchial hyperreactivity. Specific IgE antibodies to GCB extract were found in sera of 11 workers and to castor bean (CB) extract in 16. The workers measured their lung function with an air flow meter, three times a day for 1 week, and the values were lower in the second half of the week for the workers with IgE antibodies to GCB, but not for the others. It is concluded that the case history, prick test, RAST, and simple lung function tests for one or a few weeks are the best tools when investigating occupational allergy. When the allergen is unknown, but the occurrence of an IgE-mediated allergy is suspected, serial lung function measurements and determinations of total serum IgE, in addition to taking a careful case history, are valuable methods with which to start the investigation.

  17. Raman Spectroscopy Provides a Powerful Diagnostic Tool for Accurate Determination of Albumin Glycation

    PubMed Central

    Dingari, Narahara Chari; Horowitz, Gary L.; Kang, Jeon Woong; Dasari, Ramachandra R.; Barman, Ishan

    2012-01-01

    We present the first demonstration of glycated albumin detection and quantification using Raman spectroscopy without the addition of reagents. Glycated albumin is an important marker for monitoring the long-term glycemic history of diabetics, especially as its concentrations, in contrast to glycated hemoglobin levels, are unaffected by changes in erythrocyte life times. Clinically, glycated albumin concentrations show a strong correlation with the development of serious diabetes complications including nephropathy and retinopathy. In this article, we propose and evaluate the efficacy of Raman spectroscopy for determination of this important analyte. By utilizing the pre-concentration obtained through drop-coating deposition, we show that glycation of albumin leads to subtle, but consistent, changes in vibrational features, which with the help of multivariate classification techniques can be used to discriminate glycated albumin from the unglycated variant with 100% accuracy. Moreover, we demonstrate that the calibration model developed on the glycated albumin spectral dataset shows high predictive power, even at substantially lower concentrations than those typically encountered in clinical practice. In fact, the limit of detection for glycated albumin measurements is calculated to be approximately four times lower than its minimum physiological concentration. Importantly, in relation to the existing detection methods for glycated albumin, the proposed method is also completely reagent-free, requires barely any sample preparation and has the potential for simultaneous determination of glycated hemoglobin levels as well. Given these key advantages, we believe that the proposed approach can provide a uniquely powerful tool for quantification of glycation status of proteins in biopharmaceutical development as well as for glycemic marker determination in routine clinical diagnostics in the future. PMID:22393405

  18. Role of diagnostic tests in esophageal evaluation

    SciTech Connect

    Silverstein, B.D.; Pope, C.E. II

    1980-06-01

    In the evaluation of esophageal disease, the appropriate question must be asked before the correct tests can be selected. Reflux can be demonstrated by radiologic methods, pH testing or radioisotopic techniques. Esophageal mucosal damage is best evaluated by x-ray, endoscopy, or biopsy. Chest pain is demonstrated by acid infusion or by manometry. Two algorithms are presented for the evaluation of chest pain and reflux symptoms.

  19. Hydraulic Diagnostics and Fault Isolation Test Program.

    DTIC Science & Technology

    1987-02-13

    and Fault Isolation Test Program was to demonstrate and evaluate the practicality of a fault detection and isolation system on an aircraft. The...system capable of fault detection and isolation in a hydraulic subsystem through the use of sensors and a microprocessor (Fig. 1). The microprocessor...DISCUSSION 2.1 DESCRIPTION OF HYDRAULIC SYSTEM SIMULATOR The fault detection and isolation test arrangement consisted of a high pressure, lightweight

  20. Test Diagnostics of RF Effects in Integrated Circuits

    DTIC Science & Technology

    1990-02-01

    RADC-TR-89-355 Final Technical Report February 1990AD-A219 737 TEST DIAGNOSTICS OF RF EFFECTS IN INTEGRATED CIRCUITS Martin Marietta Space Systems...DIAGNOSTICS OF RF EFFECTS IN INTEGRATED CIRCUITS 12 PERSONAL AUTHOR(S) David D. Wilson, Stan Epshtein, Mark G. Rossi, Christine L. Proffitt 13a. TYPE...presents "he results of an effort to measure the RF upset susceptibilities of CMOS and low power Schottky integrated circuits and to demonstrate a

  1. The Hug-up Test: A New, Sensitive Diagnostic Test for Supraspinatus Tears

    PubMed Central

    Liu, Yu-Lei; Ao, Ying-Fang; Yan, Hui; Cui, Guo-Qing

    2016-01-01

    Background: The supraspinatus tendon is the most commonly affected tendon in rotator cuff tears. Early detection of a supraspinatus tear using an accurate physical examination is, therefore, important. However, the currently used physical tests for detecting supraspinatus tears are poor diagnostic indicators and involve a wide range of sensitivity and specificity values. Therefore, the aim of this study was to establish a new physical test for the diagnosis of supraspinatus tears and evaluate its accuracy in comparison with conventional tests. Methods: Between November 2012 and January 2014, 200 consecutive patients undergoing shoulder arthroscopy were prospectively evaluated preoperatively. The hug-up test, empty can (EC) test, full can (FC) test, Neer impingement sign, and Hawkins-Kennedy impingement sign were used and compared statistically for their accuracy in terms of supraspinatus tears, with arthroscopic findings as the gold standard. Muscle strength was precisely quantified using an electronic digital tensiometer. Results: The prevalence of supraspinatus tears was 76.5%. The hug-up test demonstrated the highest sensitivity (94.1%), with a low negative likelihood ratio (NLR, 0.08) and comparable specificity (76.6%) compared with the other four tests. The area under the receiver operating characteristic curve for the hug-up test was 0.854, with no statistical difference compared with the EC test (z = 1.438, P = 0.075) or the FC test (z = 1.498, P = 0.067). The hug-up test showed no statistical difference in terms of detecting different tear patterns according to the position (χ2 = 0.578, P = 0.898) and size (Fisher's exact test, P > 0.999) compared with the arthroscopic examination. The interobserver reproducibility of the hug-up test was high, with a kappa coefficient of 0.823. Conclusions: The hug-up test can accurately detect supraspinatus tears with a high sensitivity, comparable specificity, and low NLR compared with the conventional clinical tests and

  2. Rapid Diagnostic Tests for Malaria: A Review

    DTIC Science & Technology

    2005-06-01

    clincial trial conditions . In addition, the test strips are currently not recommended to be used without a parallel blood smear sample being examined...diagnostiques ne sont pas approuvés par Santé Canada et ils ne doivent être utilisés que dans des conditions d’essais cliniques appropriés. De plus, il n’est...small amount of laboratory equipment is unsuitable for a field medic, requiring removal of the patient (or his blood sample) from front -line duties. It

  3. Psychoacoustic Assessment of Speech Communication Systems. The Diagnostic Discrimination Test.

    ERIC Educational Resources Information Center

    Grether, Craig Blaine

    The present report traces the rationale, development and experimental evaluation of the Diagnostic Discrimination Test (DDT). The DDT is a three-choice test of consonant discriminability of the perceptual/acoustic dimensions of consonant phonemes within specific vowel contexts. The DDT was created and developed in an attempt to provide a…

  4. University Students' Perspectives on Diagnostic Testing in Mathematics

    ERIC Educational Resources Information Center

    Ní Fhloinn, Eabhnat; Bhaird, Ciarán Macan; Nolan, Brien

    2014-01-01

    Many universities issue mathematical diagnostic tests to incoming first-year students, covering a range of the basic concepts with which they should be comfortable from secondary school. As far as many lecturers are concerned, the purpose of this test is to determine the students' mathematical knowledge on entry. It should also provide an early…

  5. ACER Physics Unit Tests: Unit Tests, Diagnostic Aids, [and] Teachers Handbook.

    ERIC Educational Resources Information Center

    Australian Council for Educational Research, Hawthorn.

    The Physics Unit Tests are designed to assist in the diagnostic evaluation of students' progress in the study of physics during the last two years of secondary schooling. They consist of a collection of 21 separate tests, each related to a different topic, and 21 diagnostic aids corresponding to the tests. The topics covered are: physical…

  6. An embedded barcode for "connected" malaria rapid diagnostic tests.

    PubMed

    Scherr, Thomas F; Gupta, Sparsh; Wright, David W; Haselton, Frederick R

    2017-03-29

    Many countries are shifting their efforts from malaria control to disease elimination. New technologies will be necessary to meet the more stringent demands of elimination campaigns, including improved quality control of malaria diagnostic tests, as well as an improved means for communicating test results among field healthcare workers, test manufacturers, and national ministries of health. In this report, we describe and evaluate an embedded barcode within standard rapid diagnostic tests as one potential solution. This information-augmented diagnostic test operates on the familiar principles of traditional lateral flow assays and simply replaces the control line with a control grid patterned in the shape of a QR (quick response) code. After the test is processed, the QR code appears on both positive or negative tests. In this report we demonstrate how this multipurpose code can be used not only to fulfill the control line role of test validation, but also to embed test manufacturing details, serve as a trigger for image capture, enable registration for image analysis, and correct for lighting effects. An accompanying mobile phone application automatically captures an image of the test when the QR code is recognized, decodes the QR code, performs image processing to determine the concentration of the malarial biomarker histidine-rich protein 2 at the test line, and transmits the test results and QR code payload to a secure web portal. This approach blends automated, sub-nanomolar biomarker detection, with near real-time reporting to provide quality assurance data that will help to achieve malaria elimination.

  7. Diagnostic development and support of MHD test facilities

    SciTech Connect

    Not Available

    1990-01-01

    The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for MHD power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL's computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs. 25 figs., 6 tabs.

  8. Offering prenatal diagnostic tests: European guidelines for clinical practice [corrected].

    PubMed

    Skirton, Heather; Goldsmith, Lesley; Jackson, Leigh; Lewis, Celine; Chitty, Lyn

    2014-05-01

    For over four decades, it has been possible to offer prenatal diagnostic testing for fetal abnormalities. Prenatal testing is now available for a wide range of monogenic disorders as well as chromosomal abnormalities and should be provided within the ethical framework of informed consent and autonomous choice. However, there are no published guidelines for health professionals from varied disciplines who offer prenatal diagnosis (PND) in a range of possible settings including departments of maternity, obstetrics and clinical genetics. We used an Expert Group technique to develop a set of guidelines for provision of prenatal diagnostic services. Thirteen European health professionals, all experts in PND, participated in a workshop to develop the guidelines, which were then subjected to a wide consultation process. The objective of PND was defined as providing prenatal diagnostic testing services (for genetic conditions) that enable families to make informed choices consistent with their individual needs and values and which support them in dealing with the outcome of such testing. General principles, logistical considerations, clinical care and counselling topics are all described and are equally applicable to invasive and non-invasive testing. These guidelines provide a framework for ethical clinical care; however, they are flexible enough to enable practitioners to adapt them to their particular setting. Ideally, an individualised approach to each family is required to ensure autonomous choice and informed consent regarding prenatal diagnostic testing within the local ethical and legal framework.

  9. Diagnostics and Ancillary Tests of Neurologic Dysfunction in the Ruminant.

    PubMed

    Nagy, Dusty W

    2017-03-01

    A variety of diagnostic tests can be used to help further characterize and diagnose neurologic disease in ruminant species. Cerebrospinal fluid is easily collected, and analysis can help in defining the broad category of disease. Diagnostic imaging, including radiography, myelography, ultrasonography, computed tomography, and MRI, have all been used to varying degrees in ruminants. Advanced cross-sectional imaging techniques have the capacity to aid greatly in diagnosis, but their cost can often be prohibitive. Currently, electrodiagnostic tests are not well evaluated or used in the diagnosis of neurologic disease in ruminants.

  10. Performance of Bayesian outlier diagnostic in testing mean vector

    NASA Astrophysics Data System (ADS)

    Mohammad, Rofizah; Hamzah, Firdaus Mohamad

    2014-09-01

    The diagnostic measure kd which is used to measure the effect of a single observation d on model choice was applied to a variety of univariate model. The purpose of this study is to assess the performance of this diagnostic measure when applying to multivariate structure for testing the specified mean vector. We illustrate the method using data generated from multivariate normal distribution. If X a p-variate normal random variable of size n with the mean vector θ and a known covariance matrix, we consider the null hypothesis that the mean vector θ is zero. From this simulation we test the performance of kd for several n and p values.

  11. Evaluation of Raman spectroscopy in comparison to commonly performed dengue diagnostic tests

    NASA Astrophysics Data System (ADS)

    Khan, Saranjam; Ullah, Rahat; Khurram, Muhammad; Ali, Hina; Mahmood, Arshad; Khan, Ajmal; Ahmed, Mushtaq

    2016-09-01

    This study demonstrates the evaluation of Raman spectroscopy as a rapid diagnostic test in comparison to commonly performed tests for an accurate detection of dengue fever in human blood sera. Blood samples of 104 suspected dengue patients collected from Holy Family Hospital, Rawalpindi, Pakistan, have been used in this study. Out of 104 samples, 52 (50%) were positive based on immunoglobulin G (IgG), whereas 54 (52%) were positive based on immunoglobulin M (IgM) antibody tests. For the determination of the diagnostic capabilities of Raman spectroscopy, accuracy, sensitivity, specificity and false positive rate have been calculated in comparison to normally performed IgM and IgG captured enzyme-linked immunosorbent assay tests. Accuracy, precision, specificity, and sensitivity for Raman spectroscopy in comparison to IgM were found to be 66%, 70%, 72%, and 61%, whereas based on IgG they were 47%, 46%, 52%, and 43%, respectively.

  12. Reference module selection criteria for accurate testing of photovoltaic (PV) panels

    SciTech Connect

    Roy, J.N.; Gariki, Govardhan Rao; Nagalakhsmi, V.

    2010-01-15

    It is shown that for accurate testing of PV panels the correct selection of reference modules is important. A detailed description of the test methodology is given. Three different types of reference modules, having different I{sub SC} (short circuit current) and power (in Wp) have been used for this study. These reference modules have been calibrated from NREL. It has been found that for accurate testing, both I{sub SC} and power of the reference module must be either similar or exceed to that of modules under test. In case corresponding values of the test modules are less than a particular limit, the measurements may not be accurate. The experimental results obtained have been modeled by using simple equivalent circuit model and associated I-V equations. (author)

  13. Enhanced Liver Fibrosis (ELF) test accurately identifies liver fibrosis in patients with chronic hepatitis C.

    PubMed

    Parkes, J; Guha, I N; Roderick, P; Harris, S; Cross, R; Manos, M M; Irving, W; Zaitoun, A; Wheatley, M; Ryder, S; Rosenberg, W

    2011-01-01

    Assessment of liver fibrosis is important in determining prognosis and evaluating interventions. Due to limitations of accuracy and patient hazard of liver biopsy, non-invasive methods have been sought to provide information on liver fibrosis, including the European liver fibrosis (ELF) test, shown to have good diagnostic accuracy for the detection of moderate and severe fibrosis. Access to independent cohorts of patients has provided an opportunity to explore if this test could be simplified. This paper reports the simplification of the ELF test and its ability to identity severity of liver fibrosis in external validation studies in patients with chronic hepatitis C (CHC). Paired biopsy and serum samples from 347 naïve patients with CHC in three independent cohorts were analysed. Diagnostic performance characteristics were derived (AUROC, sensitivity and specificity, predictive values), and clinical utility modelling performed to determine the proportion of biopsies that could have been avoided if ELF test was used in this patient group. It was possible to simplify the original ELF test without loss of performance and the new algorithm is reported. The simplified ELF test was able to predict severe fibrosis [pooled AUROC of 0.85 (95% CI 0.81-0.89)] and using clinical utility modelling to predict severe fibrosis (Ishak stages 4-6; METAVIR stages 3 and 4) 81% of biopsies could have been avoided (65% correctly). Issues of spectrum effect in diagnostic test evaluations are discussed. In chronic hepatitis C a simplified ELF test can detect severe liver fibrosis with good accuracy.

  14. [Evaluation of medical diagnostic tests: application of Bayes theorem, ROC-curve and Kappa-test] .

    PubMed

    Lugosi, L; Molnár, I

    2000-07-30

    With the technical improvement of the sensitivity and specificity of the medical diagnostic tests the principles and methods of statistical analysis of the tests are in developing too. The technical development of the diagnostic tests and the exact statistical evaluation of the data will improve the reliability and effectiveness of the decisions for medical interventions. Application, statistical evaluation and interpretation of the Bayes theorem, ROC curve and Kappa test are presented.

  15. Accurate bs and w testing important for crude-oil custody transfer

    SciTech Connect

    Williams, J. )

    1990-11-12

    This paper discusses how monitoring crude-oil sediment and water content at the field production site is essential in accurate crude-oil custody transfer operations. This is accomplished by manual methods, or on-line devices like capacitance, density, or energy-absorption analyzers. For custody-transfer purposes, sediment and water is determined by a test which follows one of the API manuals of petroleum measurement standards (MPMS). Typically, this test is conducted in the field by the field centrifuge method which, if performed properly, yields very accurate results. Laboratory tests can be performed, but sample handling becomes even more critical.

  16. Diagnostics of the ITER neutral beam test facility

    SciTech Connect

    Pasqualotto, R.; Serianni, G.; Agostini, M.; Brombin, M.; Dalla Palma, M.; Gazza, E.; Pomaro, N.; Rizzolo, A.; Spolaore, M.; Zaniol, B.; Sonato, P.; De Muri, M.; Croci, G.; Gorini, G.

    2012-02-15

    The ITER heating neutral beam (HNB) injector, based on negative ions accelerated at 1 MV, will be tested and optimized in the SPIDER source and MITICA full injector prototypes, using a set of diagnostics not available on the ITER HNB. The RF source, where the H{sup -}/D{sup -} production is enhanced by cesium evaporation, will be monitored with thermocouples, electrostatic probes, optical emission spectroscopy, cavity ring down, and laser absorption spectroscopy. The beam is analyzed by cooling water calorimetry, a short pulse instrumented calorimeter, beam emission spectroscopy, visible tomography, and neutron imaging. Design of the diagnostic systems is presented.

  17. Verification and validation of diagnostic laboratory tests in clinical virology.

    PubMed

    Rabenau, Holger F; Kessler, Harald H; Kortenbusch, Marhild; Steinhorst, Andreas; Raggam, Reinhard B; Berger, Annemarie

    2007-10-01

    This review summarizes major issues of verification and validation procedures and describes minimum requirements for verification and validation of diagnostic assays in clinical virology including instructions for CE/IVD-labeled as well as for self-developed ("home-brewed") tests or test systems. It covers techniques useful for detection of virus specific antibodies, for detection of viral antigens, for detection of viral nucleic acids, and for isolation of viruses on cell cultures in the routine virology laboratory.

  18. Can Emergency Medicine Residents Predict Cost of Diagnostic Testing?

    PubMed Central

    Tainter, Christopher R.; Gentges, Joshua A.; Thomas, Stephen H.; Burns, Boyd D.

    2017-01-01

    Introduction Diagnostic testing represents a significant portion of healthcare spending, and cost should be considered when ordering such tests. Needless and excessive spending may occur without an appreciation of the impact on the larger healthcare system. Knowledge regarding the cost of diagnostic testing among emergency medicine (EM) residents has not previously been studied. Methods A survey was administered to 20 EM residents from a single ACGME-accredited three-year EM residency program, asking for an estimation of patient charges for 20 commonly ordered laboratory tests and seven radiological exams. We compared responses between residency classes to evaluate whether there was a difference based on level of training. Results The survey completion rate was 100% (20/20 residents). We noted significant discrepancies between the median resident estimates and actual charge to patient for both laboratory and radiological exams. Nearly all responses were an underestimate of the actual cost. The group median underestimation for laboratory testing was $114, for radiographs $57, and for computed tomography exams was $1,058. There was improvement in accuracy with increasing level of training. Conclusion This pilot study demonstrates that EM residents have a poor understanding of the charges burdening patients and health insurance providers. In order to make balanced decisions with regard to diagnostic testing, providers must appreciate these factors. Education regarding the cost of providing emergency care is a potential area for improvement of EM residency curricula, and warrants further attention and investigation. PMID:28116030

  19. Diagnostic development and support of MHD (magnetohydrodynamics) test facilities

    SciTech Connect

    Not Available

    1989-07-01

    Mississippi State University (MSU) is developing diagnostic instruments for Magnetohydrodynamics (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for HRSR support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with MHD Energy Center computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. MSU personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

  20. Retrospective screening of relevant pesticide metabolites in food using liquid chromatography high resolution mass spectrometry and accurate-mass databases of parent molecules and diagnostic fragment ions.

    PubMed

    Polgár, László; García-Reyes, Juan F; Fodor, Péter; Gyepes, Attila; Dernovics, Mihály; Abrankó, László; Gilbert-López, Bienvenida; Molina-Díaz, Antonio

    2012-08-03

    In recent years, the detection and characterization of relevant pesticide metabolites in food is an important task in order to evaluate their formation, kinetics, stability, and toxicity. In this article, a methodology for the systematic screening of pesticides and their main metabolites in fruit and vegetable samples is described, using LC-HRMS and accurate-mass database search of parent compounds and their diagnostic fragment ions. The approach is based on (i) search for parent pesticide molecules; (ii) search for their metabolites in the positive samples, assuming common fragmentation pathways between the metabolites and parent pesticide molecules; and (iii) search for pesticide conjugates using the data from both parent species and diagnostic fragment ions. An accurate-mass database was constructed consisting of 1396 compounds (850 parent compounds, 447 fragment ions and 99 metabolites). The screening process was performed by the software in an automated fashion. The proposed methodology was evaluated with 29 incurred samples and the output obtained was compared to standard pesticide testing methods (targeted LC-MS/MS). Examples on the application of the proposed approach are shown, including the detection of several pesticide glycosides derivatives, which were found with significantly relevant intensities. Glucose-conjugated forms of parent compounds (e.g., fenhexamid-O-glucoside) and those of metabolites (e.g., despropyl-iprodione-N-glycoside) were detected. Facing the lack of standards for glycosylated pesticides, the study was completed with the synthesis of fenhexamid-O-glucoside for quantification purposes. In some cases the pesticide derivatives were found in a relatively high ratio, drawing the attention to these kinds of metabolites and showing that they should not be neglected in multi-residue methods. The global coverage obtained on the 29 analyzed samples showed the usefulness and benefits of the proposed approach and highlights the practical

  1. Diagnostic Testing and Interpretation of Tests for Autoimmunity

    PubMed Central

    Castro, Christine; Gourley, Mark

    2010-01-01

    Laboratory testing is of great value when evaluating a patient with a suspected autoimmune disease. The results can confirm a diagnosis, estimate disease severity, aid in assessing prognosis and are useful to follow disease activity. Components of the laboratory exam include complete blood count with differential, comprehensive metabolic panel, inflammatory markers, autoantibodies, and flow cytometry. This chapter discusses these components and includes a discussion about organ-specific immunologic diseases where immunological laboratory testing is employed. Comprehensive laboratory evaluation of a suspected autoimmune illness in conjunction with a thorough clinical evaluation provides a better understanding of a patient's immunologic disease. PMID:20061009

  2. The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

    PubMed

    Huckle, David

    2015-06-01

    Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications.

  3. Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

    USGS Publications Warehouse

    Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.

    2016-01-01

    Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  4. The dilemma of diagnostic testing for Prader-Willi syndrome

    PubMed Central

    Hung, Dorothy

    2017-01-01

    Although Prader-Willi syndrome (PWS) is a well-described clinical dysmorphic syndrome, DNA testing is required for a definitive diagnosis. A definitive diagnosis can be made in approximately 99% of cases using DNA testing; there are a number of DNA tests that can be used for this purpose, although there is no set standard algorithm of testing. The dilemma arises because of the complex genetic mechanisms at the basis of PWS, which need to be elucidated. To establish the molecular mechanism with a complete work up, involves at least 2 tests. Here we discuss the commonly used tests currently available and suggest a cost—effective approach to diagnostic testing. PMID:28164030

  5. Background review for diagnostic test development for Zika virus infection

    PubMed Central

    Charrel, Rémi N; Leparc-Goffart, Isabelle; Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

    2016-01-01

    Abstract Objective To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. Methods We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain. Findings We identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated. Conclusion An international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs. PMID:27516635

  6. Integrated rapid-diagnostic-test reader platform on a cellphone.

    PubMed

    Mudanyali, Onur; Dimitrov, Stoyan; Sikora, Uzair; Padmanabhan, Swati; Navruz, Isa; Ozcan, Aydogan

    2012-08-07

    We demonstrate a cellphone-based rapid-diagnostic-test (RDT) reader platform that can work with various lateral flow immuno-chromatographic assays and similar tests to sense the presence of a target analyte in a sample. This compact and cost-effective digital RDT reader, weighing only ~65 g, mechanically attaches to the existing camera unit of a cellphone, where various types of RDTs can be inserted to be imaged in reflection or transmission modes under light-emitting diode (LED)-based illumination. Captured raw images of these tests are then digitally processed (within less than 0.2 s per image) through a smart application running on the cellphone for validation of the RDT, as well as for automated reading of its diagnostic result. The same smart application then transmits the resulting data, together with the RDT images and other related information (e.g., demographic data), to a central server, which presents the diagnostic results on a world map through geo-tagging. This dynamic spatio-temporal map of various RDT results can then be viewed and shared using internet browsers or through the same cellphone application. We tested this platform using malaria, tuberculosis (TB) and HIV RDTs by installing it on both Android-based smartphones and an iPhone. Providing real-time spatio-temporal statistics for the prevalence of various infectious diseases, this smart RDT reader platform running on cellphones might assist healthcare professionals and policymakers to track emerging epidemics worldwide and help epidemic preparedness.

  7. Practice Bulletin No. 162: Prenatal Diagnostic Testing for Genetic Disorders.

    PubMed

    2016-05-01

    Prenatal genetic diagnostic testing is intended to determine, with as much certainty as possible, whether a specific genetic disorder or condition is present in the fetus. In contrast, prenatal genetic screening is designed to assess whether a patient is at increased risk of having a fetus affected by a genetic disorder. Originally, prenatal genetic testing focused primarily on Down syndrome (trisomy 21), but now it is able to detect a broad range of genetic disorders. Although it is necessary to perform amniocentesis or chorionic villus sampling (CVS) to definitively diagnose most genetic disorders, in some circumstances, fetal imaging with ultrasonography, echocardiography, or magnetic resonance imaging may be diagnostic of a particular structural fetal abnormality that is suggestive of an underlying genetic condition.The objective of prenatal genetic testing is to detect health problems that could affect the woman, fetus, or newborn and provide the patient and her obstetrician-gynecologist or other obstetric care provider with enough information to allow a fully informed decision about pregnancy management. Prenatal genetic testing cannot identify all abnormalities or problems in a fetus, and any testing should be focused on the individual patient's risks, reproductive goals, and preferences. It is important that patients understand the benefits and limitations of all prenatal screening and diagnostic testing, including the conditions for which tests are available and the conditions that will not be detected by testing. It also is important that patients realize that there is a broad range of clinical presentations, or phenotypes, for many genetic disorders and that results of genetic testing cannot predict all outcomes. Prenatal genetic testing has many benefits, including reassuring patients when results are normal, identifying disorders for which prenatal treatment may provide benefit, optimizing neonatal outcomes by ensuring the appropriate location for

  8. Interpreting the Results of Diagnostic Testing: Some Statistics for Testing in Real Time. Methodology Project.

    ERIC Educational Resources Information Center

    McArthur, David; Chou, Chih-Ping

    Diagnostic testing confronts several challenges at once, among which are issues of test interpretation and immediate modification of the test itself in response to the interpretation. Several methods are available for administering and evaluating a test in real-time, towards optimizing the examiner's chances of isolating a persistent pattern of…

  9. Repeated tourniquet testing as a diagnostic tool in dengue infection.

    PubMed

    Norlijah, O; Khamisah, A Nor; Kamarul, A; Paeds, M; Mangalam, S

    2006-03-01

    Prospective evaluation of repeated standard tourniquet testing as a diagnostic indicator of dengue infection was done. Included were patients admitted to a children's hospital in Kuala Lumpur on a clinical suspicion of dengue infection based on the World Health Organization (WHO) criteria. A standard method of tourniquet was performed on 79 patients on a daily basis following admission. subjects and negative in the remaining 14 subjects. Fifty-eight subjects were serologically confirmed cases, 4 indeterminate and the remaining 17 subjects had negative serology. For diagnostic classification, 13 had dengue fever, 49 with dengue haemmorhagic fever (DHF) while 17 had non-dengue infection. The sensitivity and specificity of the tourniquet test was 82.8% and 23.5% respectively. The positive predictive value (PPV) was 78.7% while the negative predictive value (NPV) was 28.6%. In addition, the tourniquet test aided in the diagnosis of one-fifth of patients with DHF, who presented with a positive tourniquet test as the only bleeding manifestation. It seems that in a hospital setting, the tourniquet test adds little to the diagnosis of dengue infection/DHF. A positive tourniquet test, repeatedly performed, was found clinically useful as a preliminary screening test in dengue infection as recommended by WHO. However, it was not very specific and had a high false positive rate.

  10. [Diagnostic tests for amniotic infection: review of the literature].

    PubMed

    Figueroa-Damián, R; Garduño-Espinosa, J

    1997-01-01

    The diagnosis of intraamniotic infection (IAI) is not difficult when clinical manifestations are present, but there are patients with subclinical infections, in these cases the examination of the amniotic fluid is the most important diagnostic procedure. We made a critical review of the medical literature of diagnostic tests of IAI, according to the analysis criterion of the medical articles of the Department of Clinical Epidemiology of the McMaster University. The articles were identified looking for in the MEDLINE-CD ROOM and INDEX MEDICUS from 1991 to 1995. We identified 19 articles, none of them complied with all of the analysis criterion, none of the studies were blinded nor independently compared with a gold standard test and only five articles studied a full spectrum of patients. The articles with better methodologic design were those that studied the interleukin-6 role as diagnostic test for IAI; they showed a sensibility between 75 to 89% and a specificity of 97 to 100%; nevertheless it is still necessary to standardize the cut-off point of the interleukin-6 levels.

  11. A general diagnostic model applied to language testing data.

    PubMed

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

  12. Diagnostic application of KRAS mutation testing in uterine microglandular proliferations.

    PubMed

    Hong, Wei; Abi-Raad, Rita; Alomari, Ahmed K; Hui, Pei; Buza, Natalia

    2015-07-01

    Microglandular proliferations often pose a diagnostic challenge in small endocervical and endometrial biopsies. Microglandular hyperplasia (MGH) is one of the most common pseudoneoplastic glandular proliferations of uterine cervix, which can closely mimic endometrial adenocarcinomas (EAC) with a microglandular pattern (microglandular EAC). Although MGH is typically characterized by relatively uniform nuclei and rare to absent mitoses, atypical forms with architectural and/or cytologic deviation from the usual morphology have been previously described. Recently, a series of MGH with high mitotic activity has also been documented. Although careful morphological assessment and immunohistochemical workup can resolve the diagnostic dilemma in some cases, additional differential diagnostic tools are needed to separate both the common and atypical variants of MGH from EAC with microglandular pattern. Frequent KRAS mutation has been previously reported in endometrial complex mucinous lesions and endometrial mucinous carcinomas. However, the diagnostic utility of KRAS mutation analysis has not yet been explored in the context of cervical and endometrial microglandular lesions. Twelve mitotically active MGH cases and 15 cases of EAC with microglandular growth pattern were selected for the study. KRAS mutation analysis was performed in all cases by highly sensitive single-strand conformation polymorphism analysis. Clinical history and follow-up data were retrieved from electronic medical records. KRAS mutation was absent in all MGH cases, whereas 9 (60%) of 15 microglandular EAC cases tested positive for KRAS mutation. Our data indicate that KRAS mutation analysis may offer additional discriminatory power in separating benign MGH from EAC with microglandular pattern.

  13. Flight Test of Propulsion Monitoring and Diagnostic System

    NASA Technical Reports Server (NTRS)

    Gabel, Steve; Elgersma, Mike

    2002-01-01

    The objective of this program was to perform flight tests of the propulsion monitoring and diagnostic system (PMDS) technology concept developed by Honeywell under the NASA Advanced General Aviation Transport Experiment (AGATE) program. The PMDS concept is intended to independently monitor the performance of the engine, providing continuous status to the pilot along with warnings if necessary as well as making the data available to ground maintenance personnel via a special interface. These flight tests were intended to demonstrate the ability of the PMDS concept to detect a class of selected sensor hardware failures, and the ability to successfully model the engine for the purpose of engine diagnosis.

  14. A support vector machine model provides an accurate transcript-level-based diagnostic for major depressive disorder

    PubMed Central

    Yu, J S; Xue, A Y; Redei, E E; Bagheri, N

    2016-01-01

    Major depressive disorder (MDD) is a critical cause of morbidity and disability with an economic cost of hundreds of billions of dollars each year, necessitating more effective treatment strategies and novel approaches to translational research. A notable barrier in addressing this public health threat involves reliable identification of the disorder, as many affected individuals remain undiagnosed or misdiagnosed. An objective blood-based diagnostic test using transcript levels of a panel of markers would provide an invaluable tool for MDD as the infrastructure—including equipment, trained personnel, billing, and governmental approval—for similar tests is well established in clinics worldwide. Here we present a supervised classification model utilizing support vector machines (SVMs) for the analysis of transcriptomic data readily obtained from a peripheral blood specimen. The model was trained on data from subjects with MDD (n=32) and age- and gender-matched controls (n=32). This SVM model provides a cross-validated sensitivity and specificity of 90.6% for the diagnosis of MDD using a panel of 10 transcripts. We applied a logistic equation on the SVM model and quantified a likelihood of depression score. This score gives the probability of a MDD diagnosis and allows the tuning of specificity and sensitivity for individual patients to bring personalized medicine closer in psychiatry. PMID:27779627

  15. Ultrasonic diagnostic load testing of steel highway bridges

    NASA Astrophysics Data System (ADS)

    Mandracchia, Efrain A.

    1996-11-01

    This paper presents a new product, the SonicForce Acoustic Strain Gauge (ASG), that utilizes a non-contact ultrasonic technology to measure applied strain requiring no paint removal and minimal surface preparation. After an overview of the ultrasonic technology is presented the results of a diagnostic test utilizing a prototype of the ASG will be discussed. The purpose of this test was to validate the ASG as being functionally equivalent to the resistance strain gauge, and to demonstrate a cost effective enabling technology to the civil and structural engineering communities. The diagnostic tests program was supervised by Dr. Abba Lichtenstein in accordance with accepted guidelines contained in the manual for 'Rating Bridges Through Testing'. FOr the purpose of this study the bridge superstructure was modeled and structural loading profiles were determined using both resistive and acoustic strain measurement techniques. Measured strains as determined by the ASG were compared to theoretical loads in order to determine if the rodeo gulch superstructure was operating in a safe and reliable manner. Additionally, under the direction of Phil Fish, two pre-production ASGs were used to monitor accumulated cyclic loading. These test data presented as a time series strip chart and rainflow histogram.

  16. Metagenomic abundance estimation and diagnostic testing on species level

    PubMed Central

    Lindner, Martin S.; Renard, Bernhard Y.

    2013-01-01

    One goal of sequencing-based metagenomic community analysis is the quantitative taxonomic assessment of microbial community compositions. In particular, relative quantification of taxons is of high relevance for metagenomic diagnostics or microbial community comparison. However, the majority of existing approaches quantify at low resolution (e.g. at phylum level), rely on the existence of special genes (e.g. 16S), or have severe problems discerning species with highly similar genome sequences. Yet, problems as metagenomic diagnostics require accurate quantification on species level. We developed Genome Abundance Similarity Correction (GASiC), a method to estimate true genome abundances via read alignment by considering reference genome similarities in a non-negative LASSO approach. We demonstrate GASiC’s superior performance over existing methods on simulated benchmark data as well as on real data. In addition, we present applications to datasets of both bacterial DNA and viral RNA source. We further discuss our approach as an alternative to PCR-based DNA quantification. PMID:22941661

  17. Astronomy Diagnostic Test Results Reflect Course Goals and Show Room for Improvement

    NASA Astrophysics Data System (ADS)

    Lopresto, Michael C.

    The results of administering the Astronomy Diagnostic Test (ADT) to introductory astronomy students at Henry Ford Community College over three years have shown gains comparable with national averages. Results have also accurately corresponded to course goals, showing greater gains in topics covered in more detail, and lower gains in topics covered in less detail. Also evident in the results were topics for which improvement of instruction is needed. These factors and the ease with which the ADT can be administered constitute evidence of the usefulness of the ADT as an assessment instrument for introductory astronomy.

  18. NREL Develops Diagnostic Test Cases to Improve Building Energy Simulation Programs (Fact Sheet)

    SciTech Connect

    Not Available

    2011-12-01

    This technical highlight describes NREL research to develop a set of diagnostic test cases for building energy simulations in order to achieve more accurate energy use and savings predictions. The National Renewable Energy Laboratory (NREL) Residential and Commercial Buildings research groups developed a set of diagnostic test cases for building energy simulations. Eight test cases were developed to test surface conduction heat transfer algorithms of building envelopes in building energy simulation programs. These algorithms are used to predict energy flow through external opaque surfaces such as walls, ceilings, and floors. The test cases consist of analytical and vetted numerical heat transfer solutions that have been available for decades, which increases confidence in test results. NREL researchers adapted these solutions for comparisons with building energy simulation results. Testing the new cases with EnergyPlus identified issues with the conduction finite difference (CondFD) heat transfer algorithm in versions 5 and 6. NREL researchers resolved these issues for EnergyPlus version 7. The new test cases will help users and developers of EnergyPlus and other building energy tools to identify and fix problems associated with solid conduction heat transfer algorithms of building envelopes and their boundary conditions. In the long term, improvements to software algorithms will result in more accurate energy use and savings predictions. NREL researchers plan to document the set of test cases and make them available for future consideration by validation standards such as ASHRAE Standard 140: Standard Method of Test for the Evaluation of Building Energy Analysis Computer Programs. EnergyPlus users will also have access to the improved CondFD model in version 7 after its next scheduled release.

  19. Integrated Rapid-Diagnostic-Test Reader Platform on a Cellphone

    PubMed Central

    Mudanyali, Onur; Dimitrov, Stoyan; Sikora, Uzair; Padmanabhan, Swati; Navruz, Isa; Ozcan, Aydogan

    2012-01-01

    We demonstrate a cellphone based Rapid-Diagnostic-Test (RDT) reader platform that can work with various lateral flow immuno-chromatographic assays and similar tests to sense the presence of a target analyte in a sample. This compact and cost-effective digital RDT reader, weighing only ~65 grams, mechanically attaches to the existing camera unit of a cellphone, where various types of RDTs can be inserted to be imaged in reflection or transmission modes under light-emitting-diode (LED) based illumination. Captured raw images of these tests are then digitally processed (within less than 0.2 sec/image) through a smart application running on the cellphone for validation of the RDT as well as for automated reading of its diagnostic result. The same smart application running on the cellphone then transmits the resulting data, together with the RDT images and other related information (e.g., demographic data) to a central server, which presents the diagnostic results on a world-map through geo-tagging. This dynamic spatio-temporal map of various RDT results can then be viewed and shared using internet browsers or through the same cellphone application. We tested this platform using malaria, tuberculosis (TB) as well as HIV RDTs by installing it on both Android based smart-phones as well as an iPhone. Providing real-time spatio-temporal statistics for the prevalence of various infectious diseases, this smart RDT reader platform running on cellphones might assist health-care professionals and policy makers to track emerging epidemics worldwide and help epidemic preparedness. PMID:22596243

  20. The Diagnostic Performance of Stool DNA Testing for Colorectal Cancer

    PubMed Central

    Zhai, Rong-Lin; Xu, Fei; Zhang, Pei; Zhang, Wan-Li; Wang, Hui; Wang, Ji-Liang; Cai, Kai-Lin; Long, Yue-Ping; Lu, Xiao-Ming; Tao, Kai-Xiong; Wang, Guo-Bin

    2016-01-01

    Abstract This meta-analysis was designed to evaluate the diagnostic performance of stool DNA testing for colorectal cancer (CRC) and compare the performance between single-gene and multiple-gene tests. MEDLINE, Cochrane, EMBASE databases were searched using keywords colorectal cancers, stool/fecal, sensitivity, specificity, DNA, and screening. Sensitivity analysis, quality assessments, and performance bias were performed for the included studies. Fifty-three studies were included in the analysis with a total sample size of 7524 patients. The studies were heterogeneous with regard to the genes being analyzed for fecal genetic biomarkers of CRC, as well as the laboratory methods being used for each assay. The sensitivity of the different assays ranged from 2% to 100% and the specificity ranged from 81% to 100%. The meta-analysis found that the pooled sensitivities for single- and multigene assays were 48.0% and 77.8%, respectively, while the pooled specificities were 97.0% and 92.7%. Receiver operator curves and diagnostic odds ratios showed no significant difference between both tests with regard to sensitivity or specificity. This meta-analysis revealed that using assays that evaluated multiple genes compared with single-gene assays did not increase the sensitivity or specificity of stool DNA testing in detecting CRC. PMID:26844449

  1. 76 FR 39110 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ... HUMAN SERVICES Centers for Medicare & Medicaid Services Medicare Program; Section 3113: The Treatment of... participate in the Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The Demonstration... Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The authorizing legislation...

  2. Bootstrap confidence intervals for the sensitivity of a quantitative diagnostic test.

    PubMed

    Platt, R W; Hanley, J A; Yang, H

    2000-02-15

    We examine bootstrap approaches to the analysis of the sensitivity of quantitative diagnostic test data. Methods exist for inference concerning the sensitivity of one or more tests for fixed levels of specificity, taking into account the variability in the sensitivity due to variability in the test values for normal subjects. However, parametric methods do not adequately account for error, particularly when the data are non-normally distributed, and non-parametric methods have low power. We implement bootstrap methods for confidence limits for the sensitivity of a test for a fixed specificity and demonstrate that under certain circumstances the bootstrap method gives more accurate confidence intervals than do other methods, while it performs at least as well as other methods in many standard situations.

  3. Recommendations for reporting results of diagnostic genetic testing (biochemical, cytogenetic and molecular genetic).

    PubMed

    Claustres, Mireille; Kožich, Viktor; Dequeker, Els; Fowler, Brain; Hehir-Kwa, Jayne Y; Miller, Konstantin; Oosterwijk, Cor; Peterlin, Borut; van Ravenswaaij-Arts, Conny; Zimmermann, Uwe; Zuffardi, Orsetta; Hastings, Ros J; Barton, David E

    2014-02-01

    Genetic test results can have considerable importance for patients, their parents and more remote family members. Clinical therapy and surveillance, reproductive decisions and genetic diagnostics in family members, including prenatal diagnosis, are based on these results. The genetic test report should therefore provide a clear, concise, accurate, fully interpretative and authoritative answer to the clinical question. The need for harmonizing reporting practice of genetic tests has been recognised by the External Quality Assessment (EQA), providers and laboratories. The ESHG Genetic Services Quality Committee has produced reporting guidelines for the genetic disciplines (biochemical, cytogenetic and molecular genetic). These guidelines give assistance on report content, including the interpretation of results. Selected examples of genetic test reports for all three disciplines are provided in an annexe.

  4. Effect of Culture-Independent Diagnostic Tests on Future Emerging Infections Program Surveillance.

    PubMed

    Langley, Gayle; Besser, John; Iwamoto, Martha; Lessa, Fernanda C; Cronquist, Alicia; Skoff, Tami H; Chaves, Sandra; Boxrud, Dave; Pinner, Robert W; Harrison, Lee H

    2015-09-01

    The Centers for Disease Control and Prevention Emerging Infections Program (EIP) network conducts population-based surveillance for pathogens of public health importance. Central to obtaining estimates of disease burden and tracking microbiological characteristics of these infections is accurate laboratory detection of pathogens. The use of culture-independent diagnostic tests (CIDTs) in clinical settings presents both opportunities and challenges to EIP surveillance. Because CIDTs offer better sensitivity than culture and are relatively easy to perform, their use could potentially improve estimates of disease burden. However, changes in clinical testing practices, use of tests with different sensitivities and specificities, and changes to case definitions make it challenging to monitor trends. Isolates are still needed for performing strain typing, antimicrobial resistance testing, and identifying other molecular characteristics of organisms. In this article, we outline current and future EIP activities to address issues associated with adoption of CIDTs, which may apply to other public health surveillance.

  5. Epidemiology and diagnostic testing for hemochromatosis and iron overload.

    PubMed

    Adams, P C

    2015-05-01

    Hemochromatosis is the most common genetic disease in northern European populations. Body iron stores progressively increase in most patients, which can lead to cirrhosis of the liver, hepatocellular carcinoma, heart failure, arthritis, and pigmentation. Simple blood tests such as the serum ferritin and transferrin saturation are useful to suggest the diagnosis which can be confirmed in most cases with a simple genetic test for the C282Y mutation of the HFE gene. However, these blood tests are often misinterpreted and there are rare patients with iron overload without HFE mutations. A diagnostic approach is presented based on a large referral practice and a population-based study (HEIRS) which screened for iron overload in 101,168 participants.

  6. Classification of chronic orofacial pain using an intravenous diagnostic test.

    PubMed

    Tjakkes, G-H E; De Bont, L G M; Van Wijhe, M; Stegenga, B

    2009-07-01

    The aim of this study was to evaluate the ability of a preliminary intravenous diagnostic test to classify chronic orofacial pain patients into different subgroups. Patients with chronic orofacial pain conditions that could not be unambiguously diagnosed. A retrospective evaluation of series of conducted pharmacodiagnostic tests, consisting of the consecutive intravenous administration of drugs. Visual analogue scale scores were retrieved from all patients, based on which they were classified into different responder groups. In total, 46 pain profiles were analysed. Of these, 16 patients (35%) could be classified into one or more pain categories, while 30 patients (65%) could not be classified into any pain category. The pain duration or medication use did not influence the classification. Based on the results of this retrospective study, it seems that classification into subgroups is possible after intravenous testing in a minority of clinically unclassifiable patients. In patients where there is a substantial need for additional diagnostic information, these results may be of value. Recommendations are made for further research, which should include validation in patients with known pain mechanisms.

  7. Multifrequency excitation method for rapid and accurate dynamic test of micromachined gyroscope chips.

    PubMed

    Deng, Yan; Zhou, Bin; Xing, Chao; Zhang, Rong

    2014-10-17

    A novel multifrequency excitation (MFE) method is proposed to realize rapid and accurate dynamic testing of micromachined gyroscope chips. Compared with the traditional sweep-frequency excitation (SFE) method, the computational time for testing one chip under four modes at a 1-Hz frequency resolution and 600-Hz bandwidth was dramatically reduced from 10 min to 6 s. A multifrequency signal with an equal amplitude and initial linear-phase-difference distribution was generated to ensure test repeatability and accuracy. The current test system based on LabVIEW using the SFE method was modified to use the MFE method without any hardware changes. The experimental results verified that the MFE method can be an ideal solution for large-scale dynamic testing of gyroscope chips and gyroscopes.

  8. Using Combined Diagnostic Test Results to Hindcast Trends of Infection from Cross-Sectional Data

    PubMed Central

    Rydevik, Gustaf; Innocent, Giles T.; Marion, Glenn; White, Piran C. L.; Billinis, Charalambos; Barrow, Paul; Mertens, Peter P. C.; Gavier-Widén, Dolores; Hutchings, Michael R.

    2016-01-01

    Infectious disease surveillance is key to limiting the consequences from infectious pathogens and maintaining animal and public health. Following the detection of a disease outbreak, a response in proportion to the severity of the outbreak is required. It is thus critical to obtain accurate information concerning the origin of the outbreak and its forward trajectory. However, there is often a lack of situational awareness that may lead to over- or under-reaction. There is a widening range of tests available for detecting pathogens, with typically different temporal characteristics, e.g. in terms of when peak test response occurs relative to time of exposure. We have developed a statistical framework that combines response level data from multiple diagnostic tests and is able to ‘hindcast’ (infer the historical trend of) an infectious disease epidemic. Assuming diagnostic test data from a cross-sectional sample of individuals infected with a pathogen during an outbreak, we use a Bayesian Markov Chain Monte Carlo (MCMC) approach to estimate time of exposure, and the overall epidemic trend in the population prior to the time of sampling. We evaluate the performance of this statistical framework on simulated data from epidemic trend curves and show that we can recover the parameter values of those trends. We also apply the framework to epidemic trend curves taken from two historical outbreaks: a bluetongue outbreak in cattle, and a whooping cough outbreak in humans. Together, these results show that hindcasting can estimate the time since infection for individuals and provide accurate estimates of epidemic trends, and can be used to distinguish whether an outbreak is increasing or past its peak. We conclude that if temporal characteristics of diagnostics are known, it is possible to recover epidemic trends of both human and animal pathogens from cross-sectional data collected at a single point in time. PMID:27384712

  9. Validation of Three Early Ejaculation Diagnostic Tools: A Composite Measure Is Accurate and More Adequate for Diagnosis by Updated Diagnostic Criteria

    PubMed Central

    Jern, Patrick; Piha, Juhana; Santtila, Pekka

    2013-01-01

    Purpose To validate three early ejaculation diagnostic tools, and propose a new tool for diagnosis in line with proposed changes to diagnostic criteria. Significant changes to diagnostic criteria are expected in the near future. Available screening tools do not necessarily reflect proposed changes. Materials and Methods Data from 148 diagnosed early ejaculation patients (Mage = 42.8) and 892 controls (Mage = 33.1 years) from a population-based sample were used. Participants responded to three different questionnaires (Premature Ejaculation Profile; Premature Ejaculation Diagnostic Tool; Multiple Indicators of Premature Ejaculation). Stopwatch measured ejaculation latency times were collected from a subsample of early ejaculation patients. We used two types of responses to the questionnaires depending on the treatment status of the patients 1) responses regarding the situation before starting pharmacological treatment and 2) responses regarding current situation. Logistic regressions and Receiver Operating Characteristics were used to assess ability of both the instruments and individual items to differentiate between patients and controls. Results All instruments had very good precision (Areas under the Curve ranging from .93-.98). A new five-item instrument (named CHecklist for Early Ejaculation Symptoms – CHEES) consisting of high-performance variables selected from the three instruments had validity (Nagelkerke R2 range .51-.79 for backwards/forwards logistic regression) equal to or slightly better than any individual instrument (i.e., had slightly higher validity statistics, but these differences did not achieve statistical significance). Importantly, however, this instrument was more in line with proposed changes to diagnostic criteria. Conclusions All three screening tools had good validity. A new 5-item diagnostic tool (CHEES) based on the three instruments had equal or somewhat more favorable validity statistics compared to the other three tools, but is

  10. Using Three-Tier Diagnostic Test to Assess Students' Misconceptions of States of Matter

    ERIC Educational Resources Information Center

    Kirbulut, Zubeyde Demet; Geban, Omer

    2014-01-01

    This study involves the development of a three-tier diagnostic test to measure high school students' understanding of states of matter concepts. The States of Matter Diagnostic Test (SMDT) is a 19-item three-tier diagnostic test consisting of three-tier items for assessing students' understanding of states of matter concepts. The SMDT was…

  11. Fan Noise Source Diagnostic Test: Rotor Alone Aerodynamic Performance Results

    NASA Technical Reports Server (NTRS)

    Hughes, Christopher E.; Jeracki, Robert J.; Woodward, Richard P.; Miller, Christopher J.

    2005-01-01

    The aerodynamic performance of an isolated fan or rotor alone model was measured in the NASA Glenn Research Center 9- by 15- Foot Low Speed Wind Tunnel as part of the Fan Broadband Source Diagnostic Test conducted at NASA Glenn. The Source Diagnostic Test was conducted to identify the noise sources within a wind tunnel scale model of a turbofan engine and quantify their contribution to the overall system noise level. The fan was part of a 1/5th scale model representation of the bypass stage of a current technology turbofan engine. For the rotor alone testing, the fan and nacelle, including the inlet, external cowl, and fixed area fan exit nozzle, were modeled in the test hardware; the internal outlet guide vanes located behind the fan were removed. Without the outlet guide vanes, the velocity at the nozzle exit changes significantly, thereby affecting the fan performance. As part of the investigation, variations in the fan nozzle area were tested in order to match as closely as possible the rotor alone performance with the fan performance obtained with the outlet guide vanes installed. The fan operating performance was determined using fixed pressure/temperature combination rakes and the corrected weight flow. The performance results indicate that a suitable nozzle exit was achieved to be able to closely match the rotor alone and fan/outlet guide vane configuration performance on the sea level operating line. A small shift in the slope of the sea level operating line was measured, which resulted in a slightly higher rotor alone fan pressure ratio at take-off conditions, matched fan performance at cutback conditions, and a slightly lower rotor alone fan pressure ratio at approach conditions. However, the small differences in fan performance at all fan conditions were considered too small to affect the fan acoustic performance.

  12. Diagnostic Tests for Entering and Departing Undergraduate Students

    NASA Astrophysics Data System (ADS)

    Waltham, Chris; Kotlicki, A.

    2006-12-01

    A diagnostic test administered at the start of a class should test basic concepts which are recognized as course prerequisites. The questions should not be over-packaged: e.g. students should be required to create models, rather than this being done for them each time. Students should be allowed great latitude in their answers, so we can discover what they are thinking. When administered at the end of a class the goals should be similar: testing concepts taught in the class itself and the retention of necessary concepts from previous classes. Great care has to be taken to avoid teaching to the test. In assessing an entire program, for example an undergraduate majors degree in physics, then one looks for very general skills and knowledge not specific to any one course. The purpose of an undergraduate degree in physics (or indeed any science) is to equip the students with a set of problem-solving skills and basic knowledge which can be applied in a large variety of workplace settings and to allow that student to contribute to civic society as a science-literate person. The creator of any diagnostic test should always have these big goals in mind. We have developed a set of questions which we think fulfill these criteria, yet are not specific to any particular level of science education. They have been administered to students in secondary schools across Canada, incoming first-year science students and final-year physics students at the University of British Columbia. The results will be presented.

  13. Reactor protection system with automatic self-testing and diagnostic

    DOEpatents

    Gaubatz, D.C.

    1996-12-17

    A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically ``identical`` values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic. 16 figs.

  14. Reactor protection system with automatic self-testing and diagnostic

    DOEpatents

    Gaubatz, Donald C.

    1996-01-01

    A reactor protection system having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically "identical" values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic.

  15. The Astronomy Diagnostic Test: Past, Present and Future

    NASA Astrophysics Data System (ADS)

    Deming, G. L.; Hufnagel, B. R.

    2000-12-01

    During 1998, the Collaboration for Astronomy Education Research (Adams, Adrian, Brick, Deming, Hufnagel, Slater, and Zeilik) developed a content-based diagnostic test for undergraduate non-science majors taking their first introductory level astronomy course. Student interviews and written feedback were used to construct a series of questions reflecting the students' natural language and with distractors (wrong answers) that mirror commonly held misconceptions. Version 1.9 of the Astronomy Diagnostic Test (ADT) was administered during Spring 1999 by volunteers teaching astronomy at 22 institutions across the United States. Minor modifications were made and Version 2.0 was released on June 21, 1999. The ADT 2.0 currently is available to the astronomical community through two websites and we continue to collect pretest/posttest results. Award of an NSF Small Grant for Exploratory Research has enabled us to work with a team of education researchers at the Ontario Institute for Studies in Education. Our database will be subjected to a statistical analysis in order to establish reliability of ADT 2.0. In addition, content, face, and construct validity are being examined. If you are teaching an introductory astronomy course aimed at non-science majors for Spring 2001, your class can be part of this project. We are looking for volunteers! We are also interested in hearing your ideas for a "next-generation" version of the ADT. Funding provided by NSF grant REC-0089239

  16. Application of neural networks to flight test diagnostics

    SciTech Connect

    Wheeler, R.M. Jr.; Sheaffer, D.A.

    1991-08-01

    A system has been designed which can provide summary information about specific noisy electric pulses that are generated during flight testing. This is important from a telemetry viewpoint, since limited bandwidth often rules out transmitting all of the pulse data. The system is based on a neural network processing paradigm. The neural network serves as a mapping between pulse data inputs and pulse category outputs. Output categories correspond to presence or type of component failure. Extensive computer simulations have shown that the system can recognize qualitative pulse features which are useful for diagnostic purposes. A second version of the system, also using a neural network, was designed to perform data compression. In this case, an entire pulse is efficiently coded for transmission and the original signal is reconstructed upon receiving the coded transmission. Successful simulations for both systems have demonstrated feasibility and have led to a hardware development effort aimed at prototyping a fieldable system. Based on these results, it appears that the neural network approach may be applicable to other diagnostic and data analysis problems arising in component or system testing. 3 refs., 16 figs., 2 tabs.

  17. The bone diagnostic instrument III: Testing mouse femora

    NASA Astrophysics Data System (ADS)

    Randall, Connor; Mathews, Phillip; Yurtsev, Eugene; Sahar, Nadder; Kohn, David; Hansma, Paul

    2009-06-01

    Here we describe modifications that allow the bone diagnostic instrument (BDI) [P. Hansma et al., Rev. Sci. Instrum. 79, 064303 (2008); Rev. Sci. Instrum. 77, 075105 (2006)], developed to test human bone, to test the femora of mice. These modifications include reducing the effective weight of the instrument on the bone, designing and fabricating new probe assemblies to minimize damage to the small bone, developing new testing protocols that involve smaller testing forces, and fabricating a jig for securing the smaller bones for testing. With these modifications, the BDI was used to test the hypothesis that short-term running has greater benefit on the mechanical properties of the femur for young growing mice compared to older, skeletally mature mice. We measured elastic modulus, hardness, and indentation distance increase (IDI), which had previously been shown to be the best discriminators in model systems known to exhibit differences in mechanical properties at the whole bone level. In the young exercised murine femora, the IDI was significantly lower than in young control femora. Since IDI has a relation to postyield properties, these results suggest that exercise during bone development increases post yield mechanical competence. We were also able to measure effects of aging on bone properties with the BDI. There was a significant increase in the IDI, and a significant decrease in the elastic modulus and hardness between the young and old groups. Thus, with the modifications described here, the BDI can take measurements on mouse bones and obtain statistically significant results.

  18. Digital test signal generation: An accurate SNR calibration approach for the DSN

    NASA Technical Reports Server (NTRS)

    Gutierrez-Luaces, B. O.

    1991-01-01

    A new method of generating analog test signals with accurate signal to noise ratios (SNRs) is described. High accuracy will be obtained by simultaneous generation of digital noise and signal spectra at a given baseband or bandpass limited bandwidth. The digital synthesis will provide a test signal embedded in noise with the statistical properties of a stationary random process. Accuracy will only be dependent on test integration time with a limit imposed by the system quantization noise (expected to be 0.02 dB). Setability will be approximately 0.1 dB. The first digital SNR generator to provide baseband test signals is being built and will be available in early 1991.

  19. A simple diagnostic test for Fanconi anemia by flow cytometry.

    PubMed

    Miglierina, R; Le Coniat, M; Berger, R

    1991-03-01

    A simple diagnostic test for Fanconi anemia (FA) by flow cytometry is proposed. It is based on the cell cycle disturbances of FA cells and their sensitisation by alkylating agents. Following PHA-stimulation of whole blood cell cultures in the presence or absence of nitrogen mustard, the accumulation of cells in G2/M phase was measured. A sharp increase of cells in G2/M was observed in cultures from FA patients when nitrogen mustard was added. This increase allows one to distinguish FA patients from patients with anemias of other origin, healthy controls, and FA heterozygotes, as effectively as chromosome breakage studies. The rapidity of the test and its reliability as demonstrated on the ten FA patients studied, will make the diagnosis of FA easier in centers without cytogenetic laboratory facilities.

  20. Self Diagnostic Accelerometer Testing on the C-17 Aircraft

    NASA Technical Reports Server (NTRS)

    Tokars, Roger P.; Lekki, John D.

    2013-01-01

    The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. To demonstrate the SDAs flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The SDA attachment conditions were varied from fully tight to loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first.

  1. D-dimer testing and acute venous thromboembolism. A shortcut to accurate diagnosis?

    PubMed

    Becker, D M; Philbrick, J T; Bachhuber, T L; Humphries, J E

    1996-05-13

    D-dimer fragments can be measured easily in plasma and whole blood, and the presence or absence of D-dimer could be useful in the diagnostic evaluation of venous thromboembolism. We systematically reviewed the English literature for articles that compared D-dimer results with those of other tests for deep venous thrombosis or pulmonary embolism. Twenty-nine studies were selected for detailed review, and we noted wide variability in assay performance, heterogeneity among subjects, and failure to define absence or presence of venous thromboembolism by a comprehensive criterion standard for diagnosis. These methodologic problems limit the generalizability of the published estimates of D-dimer accuracy for deep venous thrombosis or pulmonary embolism, and the clinical utility of this potentially important test remains unproved.

  2. Accurate Cold-Test Model of Helical TWT Slow-Wave Circuits

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.; Dayton, James A., Jr.

    1997-01-01

    Recently, a method has been established to accurately calculate cold-test data for helical slow-wave structures using the three-dimensional electromagnetic computer code, MAFIA. Cold-test parameters have been calculated for several helical traveling-wave tube (TWT) slow-wave circuits possessing various support rod configurations, and results are presented here showing excellent agreement with experiment. The helical models include tape thickness, dielectric support shapes and material properties consistent with the actual circuits. The cold-test data from this helical model can be used as input into large-signal helical TWT interaction codes making it possible, for the first time, to design a complete TWT via computer simulation.

  3. ORNL/IAT ARMATURE DIAGNOSTICS DEMONSTRATION TEST REPORT

    SciTech Connect

    Allison, Stephen W; Cates, Michael R; Goedeke, Shawn; Crawford, M. T.; Ferraro, S. B.; Akerman, A.

    2005-03-01

    This test established feasibility for 'on the fly' temperature measurements of rail gun projectiles. In addition, an approach for projectile velocity measurement was also demonstrated. Insight was gained into other useful optical and fiberoptic diagnostic approaches. Instantaneous diagnostics could be critical for achieving further improvements in rail gun operation. They have the potential to enable design enhancements by providing information on the state of the armature and its relationship to the rail as it proceeds down the bore. To that end, the following was accomplished: (1) Optical fibers successfully delivered optical excitation and returned reflective and fluorescence signals as desired. (2) Luminescent coatings survived multiple firings--approximately 40 shots. (3) Optical triggering effectively synchronized an ultraviolet laser pulse to strike the moving armature. (4) Velocity measurements were successfully accomplished by either triggering on the armature front edge using two red diode lasers or by using a single laser and grooved marks a known distance apart on the armature surface. (5) Velocities ranged from 19 to 88 m/s. (6) Temperatures of 30 to 92 C were measured with a precision of about 2 C-: (a) This precision was achieved with a single laser shot and (b) Motion effect was observed but a methodology adequately corrected the result. The correction was only about 2 C. (7) Adequate signal-to-noise and measurement precision was achieved with a single laser shot.

  4. A powerful test of independent assortment that determines genome-wide significance quickly and accurately

    PubMed Central

    Stewart, W C L; Hager, V R

    2016-01-01

    In the analysis of DNA sequences on related individuals, most methods strive to incorporate as much information as possible, with little or no attention paid to the issue of statistical significance. For example, a modern workstation can easily handle the computations needed to perform a large-scale genome-wide inheritance-by-descent (IBD) scan, but accurate assessment of the significance of that scan is often hindered by inaccurate approximations and computationally intensive simulation. To address these issues, we developed gLOD—a test of co-segregation that, for large samples, models chromosome-specific IBD statistics as a collection of stationary Gaussian processes. With this simple model, the parametric bootstrap yields an accurate and rapid assessment of significance—the genome-wide corrected P-value. Furthermore, we show that (i) under the null hypothesis, the limiting distribution of the gLOD is the standard Gumbel distribution; (ii) our parametric bootstrap simulator is approximately 40 000 times faster than gene-dropping methods, and it is more powerful than methods that approximate the adjusted P-value; and, (iii) the gLOD has the same statistical power as the widely used maximum Kong and Cox LOD. Thus, our approach gives researchers the ability to determine quickly and accurately the significance of most large-scale IBD scans, which may contain multiple traits, thousands of families and tens of thousands of DNA sequences. PMID:27245422

  5. A Novel Automatic Rapid Diagnostic Test Reader Platform

    PubMed Central

    Ozkan, Haydar; Kayhan, Osman Semih

    2016-01-01

    A novel automatic Rapid Diagnostic Test (RDT) reader platform is designed to analyze and diagnose target disease by using existing consumer cameras of a laptop-computer or a tablet. The RDT reader is useable with numerous lateral immunochromatographic assays and similar biomedical tests. The system has two different components, which are 3D-printed, low-cost, tiny, and compact stand and a decision program named RDT-AutoReader 2.0. The program takes the image of RDT, crops the region of interest (ROI), and extracts the features from the control end test lines to classify the results as invalid, positive, or negative. All related patient's personal information, image of ROI, and the e-report are digitally saved and transferred to the related clinician. Condition of the patient and the progress of the disease can be monitored by using the saved data. The reader platform has been tested by taking image from used cassette RDTs of rotavirus (RtV)/adenovirus (AdV) and lateral flow strip RDTs of Helicobacter pylori (H. pylori) before discarding them. The created RDT reader can also supply real-time statistics of various illnesses by using databases and Internet. This can help to inhibit propagation of contagious diseases and to increase readiness against epidemic diseases worldwide. PMID:27190549

  6. Efficient Noninferiority Testing Procedures for Simultaneously Assessing Sensitivity and Specificity of Two Diagnostic Tests.

    PubMed

    Shan, Guogen; Amei, Amei; Young, Daniel

    2015-01-01

    Sensitivity and specificity are often used to assess the performance of a diagnostic test with binary outcomes. Wald-type test statistics have been proposed for testing sensitivity and specificity individually. In the presence of a gold standard, simultaneous comparison between two diagnostic tests for noninferiority of sensitivity and specificity based on an asymptotic approach has been studied by Chen et al. (2003). However, the asymptotic approach may suffer from unsatisfactory type I error control as observed from many studies, especially in small to medium sample settings. In this paper, we compare three unconditional approaches for simultaneously testing sensitivity and specificity. They are approaches based on estimation, maximization, and a combination of estimation and maximization. Although the estimation approach does not guarantee type I error, it has satisfactory performance with regard to type I error control. The other two unconditional approaches are exact. The approach based on estimation and maximization is generally more powerful than the approach based on maximization.

  7. Reporting Diagnostic Scores in Educational Testing: Temptations, Pitfalls, and Some Solutions

    ERIC Educational Resources Information Center

    Sinharay, Sandip; Puhan, Gautam; Haberman, Shelby J.

    2010-01-01

    Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting…

  8. NSGC practice guideline: prenatal screening and diagnostic testing options for chromosome aneuploidy.

    PubMed

    Wilson, K L; Czerwinski, J L; Hoskovec, J M; Noblin, S J; Sullivan, C M; Harbison, A; Campion, M W; Devary, K; Devers, P; Singletary, C N

    2013-02-01

    The BUN and FASTER studies, two prospective multicenter trials in the United States, validated the accuracy and detection rates of first and second trimester screening previously reported abroad. These studies, coupled with the 2007 release of the American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin that endorsed first trimester screening as an alternative to traditional second trimester multiple marker screening, led to an explosion of screening options available to pregnant women. ACOG also recommended that invasive diagnostic testing for chromosome aneuploidy be made available to all women regardless of maternal age. More recently, another option known as Non-invasive Prenatal Testing (NIPT) became available to screen for chromosome aneuploidy. While screening and testing options may be limited due to a variety of factors, healthcare providers need to be aware of the options in their area in order to provide their patients with accurate and reliable information. If not presented clearly, patients may feel overwhelmed at the number of choices available. The following guideline includes recommendations for healthcare providers regarding which screening or diagnostic test should be offered based on availability, insurance coverage, and timing of a patient's entry into prenatal care, as well as a triage assessment so that a general process can be adapted to unique situations.

  9. Point-of-care cardiac troponin test accurately predicts heat stroke severity in rats.

    PubMed

    Audet, Gerald N; Quinn, Carrie M; Leon, Lisa R

    2015-11-15

    Heat stroke (HS) remains a significant public health concern. Despite the substantial threat posed by HS, there is still no field or clinical test of HS severity. We suggested previously that circulating cardiac troponin (cTnI) could serve as a robust biomarker of HS severity after heating. In the present study, we hypothesized that (cTnI) point-of-care test (ctPOC) could be used to predict severity and organ damage at the onset of HS. Conscious male Fischer 344 rats (n = 16) continuously monitored for heart rate (HR), blood pressure (BP), and core temperature (Tc) (radiotelemetry) were heated to maximum Tc (Tc,Max) of 41.9 ± 0.1°C and recovered undisturbed for 24 h at an ambient temperature of 20°C. Blood samples were taken at Tc,Max and 24 h after heat via submandibular bleed and analyzed on ctPOC test. POC cTnI band intensity was ranked using a simple four-point scale via two blinded observers and compared with cTnI levels measured by a clinical blood analyzer. Blood was also analyzed for biomarkers of systemic organ damage. HS severity, as previously defined using HR, BP, and recovery Tc profile during heat exposure, correlated strongly with cTnI (R(2) = 0.69) at Tc,Max. POC cTnI band intensity ranking accurately predicted cTnI levels (R(2) = 0.64) and HS severity (R(2) = 0.83). Five markers of systemic organ damage also correlated with ctPOC score (albumin, alanine aminotransferase, blood urea nitrogen, cholesterol, and total bilirubin; R(2) > 0.4). This suggests that cTnI POC tests can accurately determine HS severity and could serve as simple, portable, cost-effective HS field tests.

  10. SSME HPOTP post-test diagnostic system enhancement project

    NASA Astrophysics Data System (ADS)

    Bickmore, Timothy W.

    1995-01-01

    An assessment of engine and component health is routinely made after each test or flight firing of a space shuttle main engine (SSME). Currently, this health assessment is done by teams of engineers who manually review sensor data, performance data, and engine and component operating histories. Based on review of information from these various sources, an evaluation is made as to the health of each component of the SSME and the preparedness of the engine for another test or flight. The objective of this project is to further develop a computer program which automates the analysis of test data from the SSME high-pressure oxidizer turbopump (HPOTP) in order to detect and diagnose anomalies. This program fits into a larger system, the SSME Post-Test Diagnostic System (PTDS), which will eventually be extended to assess the health and status of most SSME components on the basis of test data analysis. The HPOTP module is an expert system, which uses 'rules-of-thumb' obtained from interviews with experts from NASA Marshall Space Flight Center (MSFC) to detect and diagnose anomalies. Analyses of the raw test data are first performed using pattern recognition techniques which result in features such as spikes, shifts, peaks, and drifts being detected and written to a database. The HPOTP module then looks for combination of these features which are indicative of known anomalies, using the rules gathered from the turbomachinery experts. Results of this analysis are then displayed via a graphical user interface which provides ranked lists of anomalies and observations by engine component, along with supporting data plots for each.

  11. Mutual Information Item Selection Method in Cognitive Diagnostic Computerized Adaptive Testing with Short Test Length

    ERIC Educational Resources Information Center

    Wang, Chun

    2013-01-01

    Cognitive diagnostic computerized adaptive testing (CD-CAT) purports to combine the strengths of both CAT and cognitive diagnosis. Cognitive diagnosis models aim at classifying examinees into the correct mastery profile group so as to pinpoint the strengths and weakness of each examinee whereas CAT algorithms choose items to determine those…

  12. Molecular and biological diagnostic tests for monitoring benzimidazole resistance in human soil-transmitted helminths.

    PubMed

    Diawara, Aïssatou; Schwenkenbecher, Jan M; Kaplan, Ray M; Prichard, Roger K

    2013-06-01

    In endemic countries with soil-transmitted helminths mass drug administration with albendazole or mebendazole are being implemented as a control strategy. However, it is well known in veterinary helminths that the use of the same benzimidazole drugs can place selection on the β-tubulin gene, leading to resistance. Given the concern that resistance could arise in human soil-transmitted helminths, there is an urgent need to develop accurate diagnostic tools for monitoring resistance. In this study, we developed molecular assays to detect putative resistance genetic changes in Ascaris lumbricoides, Trichuris trichiura, and hookworms, and we optimized an egg hatch assay for the canine hookworm Ancylostoma caninum and applied it to Necator americanus. Both assays were tested on field samples. The molecular assays demonstrated their reproducibility and capacity to detect the presence of worms carrying putative resistance-associated genetic changes. However, further investigations are needed to validate our molecular and biological tests on additional field isolates.

  13. Birth of the Astronomy Diagnostic Test: Prototest Evolution

    NASA Astrophysics Data System (ADS)

    Zeilik, M.

    2001-12-01

    In 1992, with funding by the National Science Foundation, a multidisciplinary research team at the University of New Mexico accreted to transform a "traditional Astro 101" course into a conceptually-oriented one. The team consisted of people from astronomy, cognitive psychology, and education. Our aim was to improve the learning environment in a large "lecture" course based on current cognitive models of adult learning. We demanded that our effort be research-based, but found little in the literature to assist us; for example, no field-tested assessment tools that would measure appropiate outcomes had been developed in higher education. From prior research at lower grades, we saw the need of a valid and reliable "misconceptions" test. We also desired to tap into higher level conceptual learning, and so developed concept map assessments to measure acquisition of the "Big Picture" in astronomy. These "misconceptions measures" were protoversions of the Astronomy Diagnostic Test (ADT) that gained in structure and usefulness over four semesters involving hundreds of students. I will outline our methodology to develop the ADT in a bootstrap way, its basis as a learning tool, and its correlation with other assessments (especially the concept maps) and achievement in the UNM "Astro 101" course. This work was supported in part by NSF DUE grants 9253983 and 9981155.

  14. What's in a Name? The Impact of Accurate Staphylococcus pseudintermedius Identification on Appropriate Antimicrobial Susceptibility Testing

    PubMed Central

    2016-01-01

    Bacteria in the Staphylococcus intermedius group, including Staphylococcus pseudintermedius, often encode mecA-mediated methicillin resistance. Reliable detection of this phenotype for proper treatment and infection control decisions requires that these coagulase-positive staphylococci are accurately identified and specifically that they are not misidentified as S. aureus. As correct species level bacterial identification becomes more commonplace in clinical laboratories, one can expect to see changes in guidance for antimicrobial susceptibility testing and interpretation. The study by Wu et al. in this issue (M. T. Wu, C.-A. D. Burnham, L. F. Westblade, J. Dien Bard, S. D. Lawhon, M. A. Wallace, T. Stanley, E. Burd, J. Hindler, R. M. Humphries, J Clin Microbiol 54:535–542, 2016, http://dx.doi.org/10.1128/JCM.02864-15) highlights the impact of robust identification of S. intermedius group organisms on the selection of appropriate antimicrobial susceptibility testing methods and interpretation. PMID:26763965

  15. Long maximal incremental tests accurately assess aerobic fitness in class II and III obese men.

    PubMed

    Lanzi, Stefano; Codecasa, Franco; Cornacchia, Mauro; Maestrini, Sabrina; Capodaglio, Paolo; Brunani, Amelia; Fanari, Paolo; Salvadori, Alberto; Malatesta, Davide

    2015-01-01

    This study aimed to compare two different maximal incremental tests with different time durations [a maximal incremental ramp test with a short time duration (8-12 min) (STest) and a maximal incremental test with a longer time duration (20-25 min) (LTest)] to investigate whether an LTest accurately assesses aerobic fitness in class II and III obese men. Twenty obese men (BMI≥35 kg.m-2) without secondary pathologies (mean±SE; 36.7±1.9 yr; 41.8±0.7 kg*m-2) completed an STest (warm-up: 40 W; increment: 20 W*min-1) and an LTest [warm-up: 20% of the peak power output (PPO) reached during the STest; increment: 10% PPO every 5 min until 70% PPO was reached or until the respiratory exchange ratio reached 1.0, followed by 15 W.min-1 until exhaustion] on a cycle-ergometer to assess the peak oxygen uptake [Formula: see text] and peak heart rate (HRpeak) of each test. There were no significant differences in [Formula: see text] (STest: 3.1±0.1 L*min-1; LTest: 3.0±0.1 L*min-1) and HRpeak (STest: 174±4 bpm; LTest: 173±4 bpm) between the two tests. Bland-Altman plot analyses showed good agreement and Pearson product-moment and intra-class correlation coefficients showed a strong correlation between [Formula: see text] (r=0.81 for both; p≤0.001) and HRpeak (r=0.95 for both; p≤0.001) during both tests. [Formula: see text] and HRpeak assessments were not compromised by test duration in class II and III obese men. Therefore, we suggest that the LTest is a feasible test that accurately assesses aerobic fitness and may allow for the exercise intensity prescription and individualization that will lead to improved therapeutic approaches in treating obesity and severe obesity.

  16. Accurate and fast multiple-testing correction in eQTL studies.

    PubMed

    Sul, Jae Hoon; Raj, Towfique; de Jong, Simone; de Bakker, Paul I W; Raychaudhuri, Soumya; Ophoff, Roel A; Stranger, Barbara E; Eskin, Eleazar; Han, Buhm

    2015-06-04

    In studies of expression quantitative trait loci (eQTLs), it is of increasing interest to identify eGenes, the genes whose expression levels are associated with variation at a particular genetic variant. Detecting eGenes is important for follow-up analyses and prioritization because genes are the main entities in biological processes. To detect eGenes, one typically focuses on the genetic variant with the minimum p value among all variants in cis with a gene and corrects for multiple testing to obtain a gene-level p value. For performing multiple-testing correction, a permutation test is widely used. Because of growing sample sizes of eQTL studies, however, the permutation test has become a computational bottleneck in eQTL studies. In this paper, we propose an efficient approach for correcting for multiple testing and assess eGene p values by utilizing a multivariate normal distribution. Our approach properly takes into account the linkage-disequilibrium structure among variants, and its time complexity is independent of sample size. By applying our small-sample correction techniques, our method achieves high accuracy in both small and large studies. We have shown that our method consistently produces extremely accurate p values (accuracy > 98%) for three human eQTL datasets with different sample sizes and SNP densities: the Genotype-Tissue Expression pilot dataset, the multi-region brain dataset, and the HapMap 3 dataset.

  17. Produced water toxicity tests accurately measure the produced water toxicity in marine environments?

    SciTech Connect

    Douglas, W.S.; Veil, J.A.

    1996-10-01

    U.S. Environmental Protection Agency (EPA) Region VI has issued a general permit for offshore oil and gas discharges to the Gulf of Mexico that places numerical limits on whole effluent toxicity (WEI) for produced water. Recently proposed EPA general permits for other produced water discharges in Regions VI and X also include enforceable numerical limits on WET. Clearly, the industry will be conducting extensive produced water WET testing. Unfortunately, the WET test may not accurately measure the toxicity of the chemical constituents of produced water. Rather the mortality of test organisms may be attributable to (1) the high salinity of produced water, which causes salinity shock to the organisms, or (2) an ionic imbalance caused by excesses or deficiencies of one or more of seawater`s essential ions in the test chambers. Both of these effects are likely to be mitigated in actual offshore discharge settings, where the receiving water will be seawater and substantial dilution will be probable. Thus, the additional salinity of produced water will be rapidly assimilated, and the proper marine ionic balance will be quickly restored. Regulatory authorities should be aware of these factors when interpreting WET test results.

  18. Selected diagnostic ophthalmic tests in the red kangaroo (Macropus rufus).

    PubMed

    Takle, Ginger L; Suedmeyer, W Kirk; Hunkeler, Amy

    2010-06-01

    The following tests were performed on a total of 20 eyes: Schirmer tear test, intraocular pressure (IOP), assessment of conjunctival flora, and pupillary diameter with application of topical tropicamide in 10 healthy captive red kangaroos (Macropus rufus) under manual restraint. The mean Schirmer tear test value was 22.6 +/- 6.07 mm/min. The mean intraocular pressure was 17.45 +/- 7.23 mm Hg. Values did not differ between eyes or gender for either test, but significant differences were identified for IOP values according to age. The most common bacteria isolated from the conjunctival fornix were Staphylococcus epidermidis (54.5%) and Corynebacterium sp. (18.2%). The mean onset of mydriasis after instillation of 1% tropicamide ophthalmic solution was 16.7 +/- 3.34 min and the mean duration of effect was 17.6 +/- 8.26 hr. The data obtained in this investigation will aid veterinary ophthalmologists and zoo veterinarians to diagnose ocular diseases in the red kangaroo accurately.

  19. Persistent digestive disorders in the tropics: causative infectious pathogens and reference diagnostic tests

    PubMed Central

    2013-01-01

    Background Persistent digestive disorders account for considerable disease burden in the tropics. Despite advances in understanding acute gastrointestinal infections, important issues concerning epidemiology, diagnosis, treatment and control of most persistent digestive symptomatologies remain to be elucidated. Helminths and intestinal protozoa are considered to play major roles, but the full extent of the aetiologic spectrum is still unclear. We provide an overview of pathogens causing digestive disorders in the tropics and evaluate available reference tests. Methods We searched the literature to identify pathogens that might give rise to persistent diarrhoea, chronic abdominal pain and/or blood in the stool. We reviewed existing laboratory diagnostic methods for each pathogen and stratified them by (i) microscopy; (ii) culture techniques; (iii) immunological tests; and (iv) molecular methods. Pathogen-specific reference tests providing highest diagnostic accuracy are described in greater detail. Results Over 30 pathogens may cause persistent digestive disorders. Bacteria, viruses and parasites are important aetiologic agents of acute and long-lasting symptomatologies. An integrated approach, consisting of stool culture, microscopy and/or specific immunological techniques for toxin, antigen and antibody detection, is required for accurate diagnosis of bacteria and parasites. Molecular techniques are essential for sensitive diagnosis of many viruses, bacteria and intestinal protozoa, and are increasingly utilised as adjuncts for helminth identification. Conclusions Diagnosis of the broad spectrum of intestinal pathogens is often cumbersome. There is a need for rapid diagnostic tests that are simple and affordable for resource-constrained settings, so that the management of patients suffering from persistent digestive disorders can be improved. PMID:23347408

  20. Toward a Diagnostic Test for Hidden Hearing Loss

    PubMed Central

    Léger, Agnès; Prendergast, Garreth; Kluk, Karolina; Guest, Hannah; Munro, Kevin J.

    2016-01-01

    Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstrated in animal models using histological techniques. However, diagnosis of the condition in individual humans is problematic because of (a) test reliability and (b) lack of a gold standard validation measure. Wave I of the transient-evoked auditory brainstem response is a noninvasive electrophysiological measure of auditory nerve function and has been validated in the animal models. However, in humans, Wave I amplitude shows high variability both between and within individuals. The frequency-following response, a sustained evoked potential reflecting synchronous neural activity in the rostral brainstem, is potentially more robust than auditory brainstem response Wave I. However, the frequency-following response is a measure of central activity and may be dependent on individual differences in central processing. Psychophysical measures are also affected by intersubject variability in central processing. Differential measures may help to reduce intersubject variability due to unrelated factors. A measure can be compared, within an individual, between conditions that are affected differently by cochlear synaptopathy. Validation of the metrics is also an issue. Comparisons with animal models, computational modeling, auditory nerve imaging, and human temporal bone histology are all potential options for validation, but there are technical and practical hurdles and difficulties in interpretation. Despite the obstacles, a diagnostic test for hidden hearing loss is a worthwhile goal, with important implications for clinical practice and health surveillance. PMID:27604783

  1. Evaluation of coproexamination as a diagnostic test for avian botulism

    USGS Publications Warehouse

    Jensen, W.I.

    1981-01-01

    Fecal extracts and blood sera from 113 ducks showing clinical signs of botulism were examined for Clostridium botulinum type C toxin by means of the mouse toxicity test to evaluate coproexamination as a diagnostic procedure, as compared with demonstration of toxin in serum. When death of test mice unprotected with type specific antitoxin (while protected controls survived) was the criterion, 78.8% of the sera and 5.3% of the fecal extracts were positive. When characteristic signs of intoxication in the unprotected mice was included as evidence of toxin in the specimens, these percentages increased to 86.7 and 6.2, respectively. Fecal specimens were collected hourly for the first 6 h after peroral dosing of eight mallards (Anas platyrhynchos) with 1.0 LD50 of type C toxin and at 24, 48, and 72 h from birds surviving that long. From 2 to 4 toxin-positive specimens were passed by all eight ducks during the first 6 h, five specimens were positive at 24 h, and three were positive at 48 h. Only three specimens were collected at 72 h, all of which were negative. These findings suggest that attempts to detect toxin in the feces of wild ducks might have been more successful had the birds been captured earlier in the course of the disease.

  2. Digital test signal generation: An accurate SNR calibration approach for the DSN

    NASA Technical Reports Server (NTRS)

    Gutierrez-Luaces, Benito O.

    1993-01-01

    In support of the on-going automation of the Deep Space Network (DSN) a new method of generating analog test signals with accurate signal-to-noise ratio (SNR) is described. High accuracy is obtained by simultaneous generation of digital noise and signal spectra at the desired bandwidth (base-band or bandpass). The digital synthesis provides a test signal embedded in noise with the statistical properties of a stationary random process. Accuracy is dependent on test integration time and limited only by the system quantization noise (0.02 dB). The monitor and control as well as signal-processing programs reside in a personal computer (PC). Commands are transmitted to properly configure the specially designed high-speed digital hardware. The prototype can generate either two data channels modulated or not on a subcarrier, or one QPSK channel, or a residual carrier with one biphase data channel. The analog spectrum generated is on the DC to 10 MHz frequency range. These spectra may be up-converted to any desired frequency without loss on the characteristics of the SNR provided. Test results are presented.

  3. Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance

    PubMed Central

    2016-01-01

    Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus. PMID:27478327

  4. Teaching Posttraining : Influencing Diagnostic Strategy with Instructions at Test

    ERIC Educational Resources Information Center

    Kulatunga-Moruzi, Chan; Brooks, Lee R.; Norman, Geoffrey R.

    2011-01-01

    It is believed that medical diagnosis involves two complementary processes, analytic and similarity-based. There is considerable debate as to which of these processes defines diagnostic expertise and how best to teach clinical diagnosis and reduce diagnostic errors. The purpose of these studies is to document the use of these strategies in medical…

  5. Development of a diagnostic test based on multiple continuous biomarkers with an imperfect reference test.

    PubMed

    García Barrado, Leandro; Coart, Els; Burzykowski, Tomasz

    2016-02-20

    Ignoring the fact that the reference test used to establish the discriminative properties of a combination of diagnostic biomarkers is imperfect can lead to a biased estimate of the diagnostic accuracy of the combination. In this paper, we propose a Bayesian latent-class mixture model to select a combination of biomarkers that maximizes the area under the ROC curve (AUC), while taking into account the imperfect nature of the reference test. In particular, a method for specification of the prior for the mixture component parameters is developed that allows controlling the amount of prior information provided for the AUC. The properties of the model are evaluated by using a simulation study and an application to real data from Alzheimer's disease research. In the simulation study, 100 data sets are simulated for sample sizes ranging from 100 to 600 observations, with a varying correlation between biomarkers. The inclusion of an informative as well as a flat prior for the diagnostic accuracy of the reference test is investigated. In the real-data application, the proposed model was compared with the generally used logistic-regression model that ignores the imperfectness of the reference test. Conditional on the selected sample size and prior distributions, the simulation study results indicate satisfactory performance of the model-based estimates. In particular, the obtained average estimates for all parameters are close to the true values. For the real-data application, AUC estimates for the proposed model are substantially higher than those from the 'traditional' logistic-regression model.

  6. New frontiers for diagnostic testing: taking advantage of forces changing health care.

    PubMed

    Allawi, S J; Hill, B T; Shah, N R

    1998-01-01

    The transformation of the health-care industry holds great economic potential for laboratory diagnostic testing providers who understand the five market forces driving change and who are shaping their own roles in the emerging market. Because of these trends, provider-based laboratories (PBLs) are competing with independent laboratories (ILs) for the latter's traditional client base--outpatients and nonpatients. PBLs will continue to service acute care patients while becoming more IL-like in logistics, sales, customer service, and marketing. Forced to compete on price, ILs have engaged in mega-mergers and will try to break into acute care via joint ventures. The ILs will need to choose their markets carefully, solidly integrate with parent organizations, and find ways to be profit centers. Consumers' demands also are forcing change. Consumers want accurate, legible bills and simplified eligibility determination and registration. They want an emphasis on prevention and wellness, which means that diagnostic testing must address early identification and monitoring of high-risk groups. To realize cost-efficiencies under whole-life capitation, laboratory networks must be part of a completely integrated health-care system. The laboratory of the future will be multicentered, without walls, and with quick access to information through technology.

  7. Fan Noise Source Diagnostic Test: Vane Unsteady Pressure Results

    NASA Technical Reports Server (NTRS)

    Envia, Edmane

    2002-01-01

    To investigate the nature of fan outlet guide vane pressure fluctuations and their link to rotor-stator interaction noise, time histories of vane fluctuating pressures were digitally acquired as part of the Fan Noise Source Diagnostic Test. Vane unsteady pressures were measured at seven fan tip speeds for both a radial and a swept vane configuration. Using time-domain averaging and spectral analysis, the blade passing frequency (BPF) harmonic and broadband contents of the vane pressures were individually analyzed. Significant Sound Pressure Level (SPL) reductions were observed for the swept vane relative to the radial vane for the BPF harmonics of vane pressure, but vane broadband reductions due to sweep turned out to be much smaller especially on an average basis. Cross-correlation analysis was used to establish the level of spatial coherence of broadband pressures between different locations on the vane and integral length scales of pressure fluctuations were estimated from these correlations. Two main results of this work are: (1) the average broadband level on the vane (in dB) increases linearly with the fan tip speed for both the radial and swept vanes, and (2) the broadband pressure distribution on the vane is nearly homogeneous and its integral length scale is a monotonically decreasing function of fan tip speed.

  8. Broadband Liner Optimization for the Source Diagnostic Test Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.

    2012-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

  9. Rapid non-invasive tests for diagnostics of infectious diseases

    NASA Astrophysics Data System (ADS)

    Malamud, Daniel

    2014-06-01

    A rapid test for an infectious disease that can be used at point-of-care at a physician's office, a pharmacy, or in the field is critical for the prompt and appropriate therapeutic intervention. Ultimately by treating infections early on will decrease transmission of the pathogen. In contrast to metabolic diseases or cancer where multiple biomarkers are required, infectious disease targets (e.g. antigen, antibody, nucleic acid) are simple and specific for the pathogen causing the disease. Our laboratory has focused on three major infectious disease; HIV, Tuberculosis, and Malaria. These diseases are pandemic in much of the world thus putting natives, tourists and military personnel at risk for becoming infected, and upon returning to the U.S., transmitting these diseases to their contacts. Our devices are designed to detect antigens, antibodies or nucleic acids in blood or saliva samples in less than 30 minutes. An overview describing the current status of each of the three diagnostic platforms is presented. These microfluidic point-of-care devices will be relatively inexpensive, disposable, and user friendly.

  10. 30 CFR 250.521 - When do I have to perform a casing diagnostic test?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... diagnostic test if . . . (1) fixed platform well, the casing pressure is greater than 100 psig. (2) subsea... 100 psig measured at the surface. (b) You are exempt from performing a diagnostic pressure test for... test? 250.521 Section 250.521 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL...

  11. 30 CFR 250.521 - When do I have to perform a casing diagnostic test?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... diagnostic test if . . . (1) fixed platform well, the casing pressure is greater than 100 psig. (2) subsea... 100 psig measured at the surface. (b) You are exempt from performing a diagnostic pressure test for... test? 250.521 Section 250.521 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL...

  12. 30 CFR 250.520 - When do I have to perform a casing diagnostic test?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... diagnostic test if . . . (1) fixed platform well, the casing pressure is greater than 100 psig. (2) subsea... 100 psig measured at the surface. (b) You are exempt from performing a diagnostic pressure test for... test? 250.520 Section 250.520 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL...

  13. Assessing Diagnostic Tests I: You Can't Be Too Sensitive.

    PubMed

    Jupiter, Daniel C

    2015-01-01

    Clinicians and patients are always interested in less invasive, cheaper, and faster diagnostic tests. When introducing such a test, physicians must ensure that it is reliable in its diagnoses and does not commit errors. In this article, I discuss several ways that new tests are compared against gold standard diagnostics.

  14. 40 CFR 85.2231 - On-board diagnostic test equipment requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Emission Control System Performance Warranty Short Tests § 85.2231 On-board diagnostic test equipment requirements. (a) The test system interface to the vehicle shall include a plug that conforms to SAE J1962 “Diagnostic Connector.”...

  15. Diagnostic analysis of pumping tests using derivative of dlgs/dlgt with case study.

    PubMed

    Xiao, Liang; Xu, Yongxin

    2014-09-01

    Diagnostic derivative interpretation of drawdown data from pumping tests is discussed in this paper. An emphasis is placed on the conceptualization of derivative term of dlgs/dlgt. Use of a combined plot of dlgs/dlgt and ds/dlgt is made to identify various flow patterns from variable discharge tests with infinite conditions, constant rate tests in bounded aquifers, and tests involving double porosity, which can be used to further characterize the aquifer. Compared with the standard derivative method (ds/dlgt), the combined derivative analysis of dlgs/dlgt and ds/dlgt of drawdown behaviours possesses certain advantages identified as follows: (1) the plot of dlgs/dlgt is strikingly sensitive for use in unveiling differences between pumping and recovery periods in a variable discharge test; (2) storativity (S) of pumped aquifers can be accurately evaluated by the combined plot; and (3) a quantitative assessment of double porosity behaviour can also be achieved. Based on applied case studies, Lagrange Interpolation Regression (LIR) is recommended for numerical derivative calculation. Advantages and disadvantages of LIR and traditional methods are demonstrated via a selected case study. The result of the case study confirms that LIR is a preferred method for numerical derivative calculation as it can be used to effectively minimise noisy effect during derivative processes. The proposed derivative approach provides the hydrologists with an additional tool for characterizing pumped aquifers.

  16. Does McNemar's test compare the sensitivities and specificities of two diagnostic tests?

    PubMed

    Kim, Soeun; Lee, Woojoo

    2017-02-01

    McNemar's test is often used in practice to compare the sensitivities and specificities for the evaluation of two diagnostic tests. For correct evaluation of accuracy, an intuitive recommendation is to test the diseased and the non-diseased groups separately so that the sensitivities can be compared among the diseased, and specificities can be compared among the healthy group of people. This paper provides a rigorous theoretical framework for this argument and study the validity of McNemar's test regardless of the conditional independence assumption. We derive McNemar's test statistic under the null hypothesis considering both assumptions of conditional independence and conditional dependence. We then perform power analyses to show how the result is affected by the amount of the conditional dependence under alternative hypothesis.

  17. Predictive, pre-natal and diagnostic genetic testing for Huntington's disease: the experience in Canada from 1987 to 2000.

    PubMed

    Creighton, S; Almqvist, E W; MacGregor, D; Fernandez, B; Hogg, H; Beis, J; Welch, J P; Riddell, C; Lokkesmoe, R; Khalifa, M; MacKenzie, J; Sajoo, A; Farrell, S; Robert, F; Shugar, A; Summers, A; Meschino, W; Allingham-Hawkins, D; Chiu, T; Hunter, A; Allanson, J; Hare, H; Schween, J; Collins, L; Sanders, S; Greenberg, C; Cardwell, S; Lemire, E; MacLeod, P; Hayden, M R

    2003-06-01

    Predictive and pre-natal testing for Huntington's Disease (HD) has been available since 1987. Initially this was offered by linkage analysis, which was surpassed by the advent of the direct mutation test for HD in 1993. Direct mutation analysis provided an accurate test that not only enhanced predictive and pre-natal testing, but also permitted the diagnostic testing of symptomatic individuals. The objective of this study was to investigate the uptake, utilization, and outcome of predictive, pre-natal and diagnostic testing in Canada from 1987 to April 1, 2000. A retrospective design was used; all Canadian medical genetics centres and their affiliated laboratories offering genetic testing for HD were invited to participate. A total of 15 of 22 centres (68.2%), currently offering or ever having offered genetic testing for HD, responded, providing data on test results, demographics, and clinical history. A total of 1061 predictive tests, 15 pre-natal tests, and 626 diagnostic tests were performed. The uptake for predictive testing was approximately 18% of the estimated at-risk Canadian population, ranging from 12.5% in the Maritimes to 20.7% in British Columbia. There appears to have been a decline in the rate of testing in recent years. Of the predictive tests, 45.0% of individuals were found to have an increased risk, and a preponderance of females (60.2%) sought testing. A greater proportion of those at < or = 25% risk sought predictive testing once direct CAG mutation analysis had become available (10.9% after mutation analysis vs 4.7% before mutation analysis, p = 0.0077). Very few pre-natal tests were requested. Of the 15 pre-natal tests, 12 had an increased risk, resulting in termination of pregnancy in all but one. Diagnostic testing identified 68.5% of individuals to be positive by mutation analysis, while 31.5% of those with HD-like symptoms were not found to have the HD mutation. The positive diagnostic tests included 24.5% of individuals with no known

  18. [Vasculitic Peripheral Neuropathies: Clinical Features and Diagnostic Laboratory Tests].

    PubMed

    Ogata, Katsuhisa

    2016-03-01

    Vasculitic peripheral neuropathy (VPN) occurs due to ischemic changes of peripheral nerves, resulting from a deficit of vascular blood supply due to damaged vasa nervorum leading to vasculitis. VPN usually manifests as sensorimotor or sensory disturbances accompanied by pain, presenting as a type of multiple mononeuropathy, with a scattered distribution in distal limbs. VPN may also present as a mononeuropathy, distal symmetric polyneuropathy, plexopathy, or radiculopathy. The rapidity of VPN is variable, ranging from days to months, with symptoms occasionally changing with the appearance of new lesions. Careful history taking and neurological examination provides an exact diagnosis. The most common cause of VPN is primary vasculitis predominantly affecting small vessels, including vasa nervorum, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, and polyarteritis nodosa. Similar vasculitic processes can also result from a systemic collagen disorder or secondary vasculitis. Electrophysiological studies and pathological investigation of biopsied peripheral nerves and muscles are important for diagnosis of vasculitis. Serological tests, including ANCA, are useful for diagnosis of vasculitis. Accurate neurological examinations are essential for diagnosis and evaluation of clinical course.

  19. Diagnostic testing for Clostridium difficile in Italian microbiological laboratories.

    PubMed

    Spigaglia, Patrizia; Barbanti, Fabrizio; Morandi, Matteo; Moro, Maria Luisa; Mastrantonio, Paola

    2016-02-01

    A laboratory diagnosis survey of Clostridium difficile infection (CDI) was performed in Italy in 2012-2013. Questionnaires from 278 healthcare settings from 15 regions of Italy were collected and analysed. Eighty seven percent of the laboratories declared to routinely perform CDI diagnosis, 99% of them only after the clinician's request. Among the 216 laboratories providing information on the size of the hospitals in which they were located, 65 had more than 500 beds (large hospitals), while 151 had less than 500 beds (small hospitals). The average percentage of positive tests for C. difficile toxins was 12.2%. Almost half of the laboratories (42%) used immunoenzymatic assay (EIA) for Tox A/B as a stand-alone method, while only 34% used an algorithm for CDI as indicated by the European guidelines. A low percentage of laboratories performed molecular assays or C. difficile culture, 25% and 29%, respectively. Most laboratories (161/278) declared to type C. difficile strains, the majority in collaboration with a reference laboratory. Among the 103 C. difficile clinical isolates collected during the study, 31 different PCR-ribotypes were identified. PCR-ribotype 356/607 (27%) was predominant, followed by 018 (12%). These two PCR-ribotypes show 87.5% of similarity in ribotyping profile. PCR-ribotypes 027 and 078 represented 8% and 4% of the strains, respectively. Four PCR-ribotypes (027, 033, 078 and 126) were positive for the binary toxin CDT. In particular, PCR-ribotype 033 produces only CDT, and it has recently been associated with symptomatic cases. The majority of strains were multidrug resistant. In particular, all strains PCR-ribotypes 356/607 and 018 were resistant to moxifloxacin, rifampicin, erythromycin and clindamycin. The results obtained highlight the need to raise awareness to the microbiological diagnosis of CDI among clinicians and to implement and harmonize diagnostic methods for CDI in Italian laboratories in the perspective of a future national

  20. Tourniquet Test for Dengue Diagnosis: Systematic Review and Meta-analysis of Diagnostic Test Accuracy

    PubMed Central

    Reid, Hamish; Thomas, Emma; Foster, Charlie; Darton, Thomas C.

    2016-01-01

    Background Dengue fever is a ubiquitous arboviral infection in tropical and sub-tropical regions, whose incidence has increased over recent decades. In the absence of a rapid point of care test, the clinical diagnosis of dengue is complex. The World Health Organisation has outlined diagnostic criteria for making the diagnosis of dengue infection, which includes the use of the tourniquet test (TT). Purpose To assess the quality of the evidence supporting the use of the TT and perform a diagnostic accuracy meta-analysis comparing the TT to antibody response measured by ELISA. Data Sources A comprehensive literature search was conducted in the following databases to April, 2016: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, BIOSIS, Web of Science, SCOPUS. Study Selection Studies comparing the diagnostic accuracy of the tourniquet test with ELISA for the diagnosis of dengue were included. Data Extraction Two independent authors extracted data using a standardized form. Data Synthesis A total of 16 studies with 28,739 participants were included in the meta-analysis. Pooled sensitivity for dengue diagnosis by TT was 58% (95% Confidence Interval (CI), 43%-71%) and the specificity was 71% (95% CI, 60%-80%). In the subgroup analysis sensitivity for non-severe dengue diagnosis was 55% (95% CI, 52%-59%) and the specificity was 63% (95% CI, 60%-66%), whilst sensitivity for dengue hemorrhagic fever diagnosis was 62% (95% CI, 53%-71%) and the specificity was 60% (95% CI, 48%-70%). Receiver-operator characteristics demonstrated a test accuracy (AUC) of 0.70 (95% CI, 0.66–0.74). Conclusion The tourniquet test is widely used in resource poor settings despite currently available evidence demonstrating only a marginal benefit in making a diagnosis of dengue infection alone. Registration The protocol for this systematic review was registered at PROSPERO: CRD42015020323. PMID:27486661

  1. Diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B: a meta-analysis of diagnostic test.

    PubMed

    Yin, Zhi; Zou, Jin; Li, Qiongxuan; Chen, Lizhang

    2017-01-02

    This study is aimed at evaluating the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B through a meta-analysis of diagnostic test. We conducted a comprehensive search in the Pubmed, Embase, Web of Science, and Chinese National Knowledge Infrastructure before October 31, 2016. Stata 14.0 software was used for calculation and statistical analyses. We used the sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), diagnostic odds ratio (DOR) and 95% confidence intervals (CIs) to evaluate the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B. Twenty-six studies were included in the final analyses, with a total of 8274 individuals. The pooled parameters are calculated from all studies: sensitivity of 0.69 (95%CI:0.63-0.75), specificity of 0.81 (95%CI: 0.73-0.87), PLR of 3.63 (95%CI:2.66-4.94), NLR of 0.38 (95%CI:0.32-0.44), DOR of 9.57 (95%CI: 6.67-13.74), and area under the curve (AUC) of 0.80 (95%CI: 0.76-0.83). We also conducted subgroup based on the range of cut-off values. Results from subgroup analysis showed that cut-off was the source of heterogeneity in the present study. The sensitivity and specificity of cut-off>2 were 0.69 and 0.95 with the AUC of 0.90 (95%CI: 0.87-0.92). The overall diagnostic value of FIB-4 is not very high for liver fibrosis in patients with hepatitis B. However, the diagnostic value is affected by the cut-off value. FIB-4 has relatively high diagnostic value for detecting liver fibrosis in patients with hepatitis B when the diagnostic threshold value is more than 2.0.

  2. Laboratory Diagnostics Market in East Africa: A Survey of Test Types, Test Availability, and Test Prices in Kampala, Uganda

    PubMed Central

    Schroeder, Lee F.; Elbireer, Ali; Jackson, J. Brooks; Amukele, Timothy K.

    2015-01-01

    Background Diagnostic laboratory tests are routinely defined in terms of their sensitivity, specificity, and ease of use. But the actual clinical impact of a diagnostic test also depends on its availability and price. This is especially true in resource-limited settings such as sub-Saharan Africa. We present a first-of-its-kind report of diagnostic test types, availability, and prices in Kampala, Uganda. Methods Test types (identity) and availability were based on menus and volumes obtained from clinical laboratories in late 2011 in Kampala using a standard questionnaire. As a measure of test availability, we used the Availability Index (AI). AI is the combined daily testing volumes of laboratories offering a given test, divided by the combined daily testing volumes of all laboratories in Kampala. Test prices were based on a sampling of prices collected in person and via telephone surveys in 2015. Findings Test volumes and menus were obtained for 95% (907/954) of laboratories in Kampala city. These 907 laboratories offered 100 different test types. The ten most commonly offered tests in decreasing order were Malaria, HCG, HIV serology, Syphilis, Typhoid, Urinalysis, Brucellosis, Stool Analysis, Glucose, and ABO/Rh. In terms of AI, the 100 tests clustered into three groups: high (12 tests), moderate (33 tests), and minimal (55 tests) availability. 50% and 36% of overall availability was provided through private and public laboratories, respectively. Point-of-care laboratories contributed 35% to the AI of high availability tests, but only 6% to the AI of the other tests. The mean price of the most commonly offered test types was $2.62 (range $1.83–$3.46). Interpretation One hundred different laboratory test types were in use in Kampala in late 2011. Both public and private laboratories were critical to test availability. The tests offered in point-of-care laboratories tended to be the most available tests. Prices of the most common tests ranged from $1

  3. The estimation of tumor cell percentage for molecular testing by pathologists is not accurate.

    PubMed

    Smits, Alexander J J; Kummer, J Alain; de Bruin, Peter C; Bol, Mijke; van den Tweel, Jan G; Seldenrijk, Kees A; Willems, Stefan M; Offerhaus, G Johan A; de Weger, Roel A; van Diest, Paul J; Vink, Aryan

    2014-02-01

    Molecular pathology is becoming more and more important in present day pathology. A major challenge for any molecular test is its ability to reliably detect mutations in samples consisting of mixtures of tumor cells and normal cells, especially when the tumor content is low. The minimum percentage of tumor cells required to detect genetic abnormalities is a major variable. Information on tumor cell percentage is essential for a correct interpretation of the result. In daily practice, the percentage of tumor cells is estimated by pathologists on hematoxylin and eosin (H&E)-stained slides, the reliability of which has been questioned. This study aimed to determine the reliability of estimated tumor cell percentages in tissue samples by pathologists. On 47 H&E-stained slides of lung tumors a tumor area was marked. The percentage of tumor cells within this area was estimated independently by nine pathologists, using categories of 0-5%, 6-10%, 11-20%, 21-30%, and so on, until 91-100%. As gold standard, the percentage of tumor cells was counted manually. On average, the range between the lowest and the highest estimate per sample was 6.3 categories. In 33% of estimates, the deviation from the gold standard was at least three categories. The mean absolute deviation was 2.0 categories (range between observers 1.5-3.1 categories). There was a significant difference between the observers (P<0.001). If 20% of tumor cells were considered the lower limit to detect a mutation, samples with an insufficient tumor cell percentage (<20%) would have been estimated to contain enough tumor cells in 27/72 (38%) observations, possibly causing false negative results. In conclusion, estimates of tumor cell percentages on H&E-stained slides are not accurate, which could result in misinterpretation of test results. Reliability could possibly be improved by using a training set with feedback.

  4. Diagnostic accuracy of clinical symptoms and rapid diagnostic test in group A streptococcal perianal infections in children.

    PubMed

    Cohen, Robert; Levy, Corinne; Bonacorsi, Stéphane; Wollner, Alain; Koskas, Marc; Jung, Camille; Béchet, Stéphane; Chalumeau, Martin; Cohen, Jérémie; Bidet, Philippe

    2015-01-15

    From 2009 to 2014, we prospectively enrolled 132 children with perianal infections. The presentation of painful defecation, anal fissures, and macroscopic blood in stools was highly suggestive of group A streptococcal perianal infection (probability 83.3%). We found a high sensitivity of a group A streptococcal rapid diagnostic testing (98%) but relatively low specificity (72.8%).

  5. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Payment for a new clinical diagnostic laboratory test. 414.508 Section 414.508 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new...

  6. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Payment for a new clinical diagnostic laboratory test. 414.508 Section 414.508 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new...

  7. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Payment for a new clinical diagnostic laboratory test. 414.508 Section 414.508 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new...

  8. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Payment for a new clinical diagnostic laboratory test. 414.508 Section 414.508 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new...

  9. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Payment for a new clinical diagnostic laboratory test. 414.508 Section 414.508 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new...

  10. The Diagnostic Reading Test, Survey Section, Form E: A Reliability Study.

    ERIC Educational Resources Information Center

    Pellegrine, R. J.

    The Diagnostic Reading Tests were designed to assess the reading skills of college students enrolled in reading centers. To assess the reliability of the Diagnostic Reading Tests, Survey Section, Form E (DRTE), a study was conducted with university freshmen as subjects. The DRTE was administered to 31 students in an Educational Opportunity Program…

  11. Use of Individual-level Covariates to Improve Latent Class Analysis of Trypanosoma Cruzi Diagnostic Tests

    PubMed Central

    Tustin, Aaron W.; Small, Dylan S.; Delgado, Stephen; Neyra, Ricardo Castillo; Verastegui, Manuela R.; Ancca Juárez, Jenny M.; Quispe Machaca, Víctor R.; Gilman, Robert H.; Bern, Caryn; Levy, Michael Z.

    2013-01-01

    Statistical methods such as latent class analysis can estimate the sensitivity and specificity of diagnostic tests when no perfect reference test exists. Traditional latent class methods assume a constant disease prevalence in one or more tested populations. When the risk of disease varies in a known way, these models fail to take advantage of additional information that can be obtained by measuring risk factors at the level of the individual. We show that by incorporating complex field-based epidemiologic data, in which the disease prevalence varies as a continuous function of individual-level covariates, our model produces more accurate sensitivity and specificity estimates than previous methods. We apply this technique to a simulated population and to actual Chagas disease test data from a community near Arequipa, Peru. Results from our model estimate that the first-line enzyme-linked immunosorbent assay has a sensitivity of 78% (95% CI: 62–100%) and a specificity of 100% (95% CI: 99–100%). The confirmatory immunofluorescence assay is estimated to be 73% sensitive (95% CI: 65–81%) and 99% specific (95% CI: 96–100%). PMID:24083130

  12. Use of Individual-level Covariates to Improve Latent Class Analysis of Trypanosoma Cruzi Diagnostic Tests.

    PubMed

    Tustin, Aaron W; Small, Dylan S; Delgado, Stephen; Neyra, Ricardo Castillo; Verastegui, Manuela R; Ancca Juárez, Jenny M; Quispe Machaca, Víctor R; Gilman, Robert H; Bern, Caryn; Levy, Michael Z

    2012-08-01

    Statistical methods such as latent class analysis can estimate the sensitivity and specificity of diagnostic tests when no perfect reference test exists. Traditional latent class methods assume a constant disease prevalence in one or more tested populations. When the risk of disease varies in a known way, these models fail to take advantage of additional information that can be obtained by measuring risk factors at the level of the individual. We show that by incorporating complex field-based epidemiologic data, in which the disease prevalence varies as a continuous function of individual-level covariates, our model produces more accurate sensitivity and specificity estimates than previous methods. We apply this technique to a simulated population and to actual Chagas disease test data from a community near Arequipa, Peru. Results from our model estimate that the first-line enzyme-linked immunosorbent assay has a sensitivity of 78% (95% CI: 62-100%) and a specificity of 100% (95% CI: 99-100%). The confirmatory immunofluorescence assay is estimated to be 73% sensitive (95% CI: 65-81%) and 99% specific (95% CI: 96-100%).

  13. Diagnostic laparoscopy for contralateral patent processus vaginalis and nonpalpable testes.

    PubMed

    Holcomb, G W

    1998-11-01

    Diagnostic laparoscopy can be a valuable adjunct for the surgical approach to surgical conditions in children. Two frequently employed indications for diagnostic laparoscopy in children include (1) the search for a contralateral patent processus vaginalis in a child with a known inguinal hernia and (2) localization and management in boys with a nonpalpable testis. Laparoscopy to investigate a possible contralateral patent processus vaginalis is easily performed using a 3-mm, 70 degrees telescope through the known inguinal hernia sac and requires only 5 minutes for completion. Diagnostic laparoscopy in boys with a nonpalpable testis is performed through a 5-mm cannula placed in the umbilicus and takes less than 10 minutes to accomplish. Depending on the laparoscopic findings, ligation of the testicular vessels is possible at laparoscopy in boys with an abdominal testis who appear best managed by a two-staged Fowler-Stephens operation. In addition, laparoscopic orchiectomy may be performed in teenage boys who have an atrophic testis.

  14. Test and Product Review: Pediatric Attention Disorders Diagnostic Screener

    ERIC Educational Resources Information Center

    Huang, Leesa V.

    2009-01-01

    This article presents a comprehensive evaluation of the Pediatric Attention Disorders Diagnostic Screener (PADDS). PADDS was developed as a computer-based assessment system to screen for attention and executive function disorders in children aged 6 through 12 years. The evaluation of the PADDS indicated that it can be a useful and efficient…

  15. Evaluating Diagnostic Point-of-Care Tests in Resource-Limited Settings

    PubMed Central

    Drain, Paul K; Hyle, Emily P; Noubary, Farzad; Freedberg, Kenneth A; Wilson, Douglas; Bishai, William; Rodriguez, William; Bassett, Ingrid V

    2014-01-01

    Diagnostic point-of-care (POC) testing is intended to minimize the time to obtain a test result, thereby allowing clinicians and patients to make an expeditious clinical decision. As POC tests expand into resource-limited settings (RLS), the benefits must outweigh the costs. To optimize POC testing in RLS, diagnostic POC tests need rigorous evaluations focused on relevant clinical outcomes and operational costs, which differ from evaluations of conventional diagnostic tests. Here, we reviewed published studies on POC testing in RLS, and found no clearly defined metric for the clinical utility of POC testing. Therefore, we propose a framework for evaluating POC tests, and suggest and define the term “test efficacy” to describe a diagnostic test’s capacity to support a clinical decision within its operational context. We also proposed revised criteria for an ideal diagnostic POC test in resource-limited settings. Through systematic evaluations, comparisons between centralized diagnostic testing and novel POC technologies can be more formalized, and health officials can better determine which POC technologies represent valuable additions to their clinical programs. PMID:24332389

  16. Accuracy of three diagnostic tests for determining Mycobacterium bovis infection status in live-sampled wild meerkats (Suricata suricatta).

    PubMed

    Drewe, Julian A; Dean, Gillian S; Michel, Anita L; Lyashchenko, Konstantin P; Greenwald, Rena; Pearce, Gareth P

    2009-01-01

    Accurate diagnosis of Mycobacterium bovis infection (bovine tuberculosis [bTB]) in live animals is notoriously problematic. The aim of the present study was to evaluate the diagnostic potential of 2 new serologic tests (multiantigen print immunoassay [MAPIA] and lateral flow immunoassay rapid test [RT]) in comparison with mycobacterial culture of tracheal washes for determining M. bovis infection status in a free-ranging population of wild meerkats (Suricata suricatta). During a longitudinal study lasting 2.5 years, 240 individually identifiable meerkats were each sampled up to 8 times under anesthesia every 3 months. Diagnostic accuracy was determined through Bayesian and maximum likelihood estimations of sensitivity, specificity, and likelihood ratios for each diagnostic test when used independently and in parallel to classify the disease status of individual meerkats in the absence of a gold standard. Culture of tracheal washes was highly specific (0.99; 95% confidence interval [CI] = 0.77, 1.00) but of low sensitivity (0.36; 95% CI = 0.24, 0.50) for diagnosing M. bovis-infected individuals. The longitudinal nature of the study with repeated sampling of the same individual animals served simultaneously to improve chances of detecting infection and increase confidence in a negative result in individual animals repeatedly testing negative. Although MAPIA and RT were individually of limited diagnostic use, interpreting the results of these 2 tests in parallel produced estimates of sensitivity (0.83; 95% CI = 0.67, 0.93) and specificity (0.73; 95% CI = 0.62, 0.82) high enough to usefully inform decision making when determining exposure to bTB in wild meerkats and potentially other species in which bTB poses a diagnostic challenge.

  17. Accurate relative location estimates for the North Korean nuclear tests using empirical slowness corrections

    NASA Astrophysics Data System (ADS)

    Gibbons, S. J.; Pabian, F.; Näsholm, S. P.; Kværna, T.; Mykkeltveit, S.

    2017-01-01

    Declared North Korean nuclear tests in 2006, 2009, 2013 and 2016 were observed seismically at regional and teleseismic distances. Waveform similarity allows the events to be located relatively with far greater accuracy than the absolute locations can be determined from seismic data alone. There is now significant redundancy in the data given the large number of regional and teleseismic stations that have recorded multiple events, and relative location estimates can be confirmed independently by performing calculations on many mutually exclusive sets of measurements. Using a 1-D global velocity model, the distances between the events estimated using teleseismic P phases are found to be approximately 25 per cent shorter than the distances between events estimated using regional Pn phases. The 2009, 2013 and 2016 events all take place within 1 km of each other and the discrepancy between the regional and teleseismic relative location estimates is no more than about 150 m. The discrepancy is much more significant when estimating the location of the more distant 2006 event relative to the later explosions with regional and teleseismic estimates varying by many hundreds of metres. The relative location of the 2006 event is challenging given the smaller number of observing stations, the lower signal-to-noise ratio and significant waveform dissimilarity at some regional stations. The 2006 event is however highly significant in constraining the absolute locations in the terrain at the Punggye-ri test-site in relation to observed surface infrastructure. For each seismic arrival used to estimate the relative locations, we define a slowness scaling factor which multiplies the gradient of seismic traveltime versus distance, evaluated at the source, relative to the applied 1-D velocity model. A procedure for estimating correction terms which reduce the double-difference time residual vector norms is presented together with a discussion of the associated uncertainty. The modified

  18. Accurate Relative Location Estimates for the North Korean Nuclear Tests Using Empirical Slowness Corrections

    NASA Astrophysics Data System (ADS)

    Gibbons, S. J.; Pabian, F.; Näsholm, S. P.; Kværna', T.; Mykkeltveit, S.

    2016-10-01

    Declared North Korean nuclear tests in 2006, 2009, 2013, and 2016 were observed seismically at regional and teleseismic distances. Waveform similarity allows the events to be located relatively with far greater accuracy than the absolute locations can be determined from seismic data alone. There is now significant redundancy in the data given the large number of regional and teleseismic stations that have recorded multiple events, and relative location estimates can be confirmed independently by performing calculations on many mutually exclusive sets of measurements. Using a 1-dimensional global velocity model, the distances between the events estimated using teleseismic P phases are found to be approximately 25% shorter than the distances between events estimated using regional Pn phases. The 2009, 2013, and 2016 events all take place within 1 km of each other and the discrepancy between the regional and teleseismic relative location estimates is no more than about 150 m. The discrepancy is much more significant when estimating the location of the more distant 2006 event relative to the later explosions with regional and teleseismic estimates varying by many hundreds of meters. The relative location of the 2006 event is challenging given the smaller number of observing stations, the lower signal-to-noise ratio, and significant waveform dissimilarity at some regional stations. The 2006 event is however highly significant in constraining the absolute locations in the terrain at the Punggye-ri test-site in relation to observed surface infrastructure. For each seismic arrival used to estimate the relative locations, we define a slowness scaling factor which multiplies the gradient of seismic traveltime versus distance, evaluated at the source, relative to the applied 1-d velocity model. A procedure for estimating correction terms which reduce the double-difference time residual vector norms is presented together with a discussion of the associated uncertainty. The

  19. Compact, accurate description of diagnostic neutral beam propagation and attenuation in a high temperature plasma for charge exchange recombination spectroscopy analysis.

    PubMed

    Bespamyatnov, Igor O; Rowan, William L; Granetz, Robert S

    2008-10-01

    Charge exchange recombination spectroscopy on Alcator C-Mod relies on the use of the diagnostic neutral beam injector as a source of neutral particles which penetrate deep into the plasma. It employs the emission resulting from the interaction of the beam atoms with fully ionized impurity ions. To interpret the emission from a given point in the plasma as the density of emitting impurity ions, the density of beam atoms must be known. Here, an analysis of beam propagation is described which yields the beam density profile throughout the beam trajectory from the neutral beam injector to the core of the plasma. The analysis includes the effects of beam formation, attenuation in the neutral gas surrounding the plasma, and attenuation in the plasma. In the course of this work, a numerical simulation and an analytical approximation for beam divergence are developed. The description is made sufficiently compact to yield accurate results in a time consistent with between-shot analysis.

  20. Rapid diagnostic tests for diagnosing uncomplicated non-falciparum or Plasmodium vivax malaria in endemic countries

    PubMed Central

    Abba, Katharine; Kirkham, Amanda J; Olliaro, Piero L; Deeks, Jonathan J; Donegan, Sarah; Garner, Paul; Takwoingi, Yemisi

    2014-01-01

    specificities are presented alongside 95% confidence intervals (95% CI). Main results We included 47 studies enrolling 22,862 participants. Patient characteristics, sampling methods and reference standard methods were poorly reported in most studies. RDTs detecting 'non-falciparum' parasitaemia Eleven studies evaluated Type 2 tests compared with microscopy, 25 evaluated Type 3 tests, and 11 evaluated Type 4 tests. In meta-analyses, average sensitivities and specificities were 78% (95% CI 73% to 82%) and 99% (95% CI 97% to 99%) for Type 2 tests, 78% (95% CI 69% to 84%) and 99% (95% CI 98% to 99%) for Type 3 tests, and 89% (95% CI 79% to 95%) and 98% (95% CI 97% to 99%) for Type 4 tests, respectively. Type 4 tests were more sensitive than both Type 2 (P = 0.01) and Type 3 tests (P = 0.03). Five studies compared Type 3 tests with PCR; in meta-analysis, the average sensitivity and specificity were 81% (95% CI 72% to 88%) and 99% (95% CI 97% to 99%) respectively. RDTs detecting P.vivax parasitaemia Eight studies compared pLDH tests to microscopy; the average sensitivity and specificity were 95% (95% CI 86% to 99%) and 99% (95% CI 99% to 100%), respectively. Authors' conclusions RDTs designed to detect P. vivax specifically, whether alone or as part of a mixed infection, appear to be more accurate than older tests designed to distinguish P. falciparum malaria from non-falciparum malaria. Compared to microscopy, these tests fail to detect around 5% ofP. vivax cases. This Cochrane Review, in combination with other published information about in vitro test performance and stability in the field, can assist policy-makers to choose between the available RDTs. PLAIN LANGUAGE SUMMARY Rapid tests for diagnosing malaria caused by Plasmodium vivax or other less common parasites This review summarises trials evaluating the accuracy of rapid diagnostic tests (RDTs) for diagnosing malaria due to Plasmodium vivax or other non-falciparum species. After searching for relevant studies up to December

  1. Assessment of Clinical Diagnosis, Microscopy, Rapid Diagnostic Tests, and Polymerase Chain Reaction in the Diagnosis of Plasmodium falciparum in Nigeria

    PubMed Central

    Ojurongbe, Olusola; Adegbosin, Olunike Olayeni; Taiwo, Sunday Samuel; Alli, Oyebode Armstrong Terry; Olowe, Olugbenga Adekunle; Ojurongbe, Taiwo Adetola; Bolaji, Oloyede Samuel; Adeyeba, Oluwaseyi Adegboyega

    2013-01-01

    This study compares the performance of clinical diagnosis and three laboratory diagnostic methods (thick film microscopy (TFM), rapid diagnostic test (RDT), and polymerase chain reaction (PCR)) for the diagnosis of Plasmodium falciparum in Nigeria. Using clinical criteria, 217 children were recruited into the study out of which 106 (48.8%) were positive by TFM, 84 (38.7%) by RDT, and 125 (57.6%) by PCR. Using a composite reference method generated from the three diagnostic methods, 71 (32.7%) patients were found to be truly infected and 90 (41.5%) truly uninfected, while 56 (25.8%) were misidentified as infected or noninfected. When each of the 3 diagnostic methods was compared with the composite reference, PCR had sensitivity of 97.3%, specificity of 62.5%, positive predictive value (PPV) of 56.8%, and negative predictive value (NPV) of 97.8%; microscopy had sensitivity of 77.2%, specificity of 72%, PPV of 66.9%, and NPV of 81.1%, while RDT had sensitivity of 62.3%, specificity of 87.4%, PPV of 67.7%, and NPV of 84.5%. PCR test performed best among the three methods followed by TFM and RDT in that order. The result of this study shows that clinical diagnosis cannot be relied upon for accurate diagnosis of P. falciparum in endemic areas. PMID:24371538

  2. Assessment of Clinical Diagnosis, Microscopy, Rapid Diagnostic Tests, and Polymerase Chain Reaction in the Diagnosis of Plasmodium falciparum in Nigeria.

    PubMed

    Ojurongbe, Olusola; Adegbosin, Olunike Olayeni; Taiwo, Sunday Samuel; Alli, Oyebode Armstrong Terry; Olowe, Olugbenga Adekunle; Ojurongbe, Taiwo Adetola; Bolaji, Oloyede Samuel; Adeyeba, Oluwaseyi Adegboyega

    2013-01-01

    This study compares the performance of clinical diagnosis and three laboratory diagnostic methods (thick film microscopy (TFM), rapid diagnostic test (RDT), and polymerase chain reaction (PCR)) for the diagnosis of Plasmodium falciparum in Nigeria. Using clinical criteria, 217 children were recruited into the study out of which 106 (48.8%) were positive by TFM, 84 (38.7%) by RDT, and 125 (57.6%) by PCR. Using a composite reference method generated from the three diagnostic methods, 71 (32.7%) patients were found to be truly infected and 90 (41.5%) truly uninfected, while 56 (25.8%) were misidentified as infected or noninfected. When each of the 3 diagnostic methods was compared with the composite reference, PCR had sensitivity of 97.3%, specificity of 62.5%, positive predictive value (PPV) of 56.8%, and negative predictive value (NPV) of 97.8%; microscopy had sensitivity of 77.2%, specificity of 72%, PPV of 66.9%, and NPV of 81.1%, while RDT had sensitivity of 62.3%, specificity of 87.4%, PPV of 67.7%, and NPV of 84.5%. PCR test performed best among the three methods followed by TFM and RDT in that order. The result of this study shows that clinical diagnosis cannot be relied upon for accurate diagnosis of P. falciparum in endemic areas.

  3. BRAF mutation testing with a rapid, fully integrated molecular diagnostics system

    PubMed Central

    Huang, Helen J.; Falchook, Gerald S.; Devogelaere, Benoit; Kockx, Mark; Bempt, Isabelle Vanden; Reijans, Martin; Naing, Aung; Fu, Siqing; Piha-Paul, Sarina A.; Hong, David S.; Holley, Veronica R.; Tsimberidou, Apostolia M.; Stepanek, Vanda M.; Patel, Sapna P.; Kopetz, E. Scott; Subbiah, Vivek; Wheler, Jennifer J.; Zinner, Ralph G.; Karp, Daniel D.; Luthra, Rajyalakshmi; Roy-Chowdhuri, Sinchita; Sablon, Erwin; Meric-Bernstam, Funda; Maertens, Geert; Kurzrock, Razelle

    2015-01-01

    Fast and accurate diagnostic systems are needed for further implementation of precision therapy of BRAF-mutant and other cancers. The novel IdyllaTM BRAF Mutation Test has high sensitivity and shorter turnaround times compared to other methods. We used Idylla to detect BRAF V600 mutations in archived formalin-fixed paraffin-embedded (FFPE) tumor samples and compared these results with those obtained using the cobas 4800 BRAF V600 Mutation Test or MiSeq deep sequencing system and with those obtained by a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory employing polymerase chain reaction–based sequencing, mass spectrometric detection, or next-generation sequencing. In one set of 60 FFPE tumor samples (15 with BRAF mutations per Idylla), the Idylla and cobas results had an agreement of 97%. Idylla detected BRAF V600 mutations in two additional samples. The Idylla and MiSeq results had 100% concordance. In a separate set of 100 FFPE tumor samples (64 with BRAF mutation per Idylla), the Idylla and CLIA-certified laboratory results demonstrated an agreement of 96% even though the tests were not performed simultaneously and different FFPE blocks had to be used for 9 cases. The IdyllaTM BRAF Mutation Test produced results quickly (sample to results time was about 90 minutes with about 2 minutes of hands on time) and the closed nature of the cartridge eliminates the risk of PCR contamination. In conclusion, our observations demonstrate that the Idylla test is rapid and has high concordance with other routinely used but more complex BRAF mutation–detecting tests. PMID:26330075

  4. Evaluation of Serological Diagnostic Tests for Typhoid Fever in Papua New Guinea Using a Composite Reference Standard

    PubMed Central

    Siba, Valentine; Horwood, Paul F.; Vanuga, Kilagi; Wapling, Johanna; Sehuko, Rebecca; Siba, Peter M.

    2012-01-01

    Typhoid fever remains a major global health problem. A major impediment to improving outcomes is the lack of appropriate diagnostic tools, which have not significantly improved in low-income settings for 100 years. We evaluated two commercially available rapid diagnostic tests (Tubex and TyphiDot), a prototype (TyphiRapid TR-02), and the commonly used single-serum Widal test in a previously reported high-burden area of Papua New Guinea. Samples were collected from 530 outpatients with axillary temperatures of ≥37.5°C, and analysis was conducted on all malaria-negative samples (n = 500). A composite reference standard of blood culture and PCR was used, by which 47 participants (9.4%) were considered typhoid fever positive. The sensitivity and specificity of the Tubex (51.1% and 88.3%, respectively) and TyphiDot (70.0% and 80.1%, respectively) tests were not high enough to warrant their ongoing use in this setting; however, the sensitivity and specificity for the TR-02 prototype were promising (89.4% and 85.0%, respectively). An axillary temperature of ≥38.5°C correlated with typhoid fever (P = 0.014). With an appropriate diagnostic test, conducting typhoid fever diagnosis only on patients with high-grade fever could dramatically decrease the costs associated with diagnosis while having no detrimental impact on the ability to accurately diagnose the illness. PMID:22993409

  5. Evaluation of serological diagnostic tests for typhoid fever in Papua New Guinea using a composite reference standard.

    PubMed

    Siba, Valentine; Horwood, Paul F; Vanuga, Kilagi; Wapling, Johanna; Sehuko, Rebecca; Siba, Peter M; Greenhill, Andrew R

    2012-11-01

    Typhoid fever remains a major global health problem. A major impediment to improving outcomes is the lack of appropriate diagnostic tools, which have not significantly improved in low-income settings for 100 years. We evaluated two commercially available rapid diagnostic tests (Tubex and TyphiDot), a prototype (TyphiRapid TR-02), and the commonly used single-serum Widal test in a previously reported high-burden area of Papua New Guinea. Samples were collected from 530 outpatients with axillary temperatures of ≥37.5°C, and analysis was conducted on all malaria-negative samples (n = 500). A composite reference standard of blood culture and PCR was used, by which 47 participants (9.4%) were considered typhoid fever positive. The sensitivity and specificity of the Tubex (51.1% and 88.3%, respectively) and TyphiDot (70.0% and 80.1%, respectively) tests were not high enough to warrant their ongoing use in this setting; however, the sensitivity and specificity for the TR-02 prototype were promising (89.4% and 85.0%, respectively). An axillary temperature of ≥38.5°C correlated with typhoid fever (P = 0.014). With an appropriate diagnostic test, conducting typhoid fever diagnosis only on patients with high-grade fever could dramatically decrease the costs associated with diagnosis while having no detrimental impact on the ability to accurately diagnose the illness.

  6. Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

    ERIC Educational Resources Information Center

    Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

    2013-01-01

    An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

  7. Doppler diagnostics of laser-ablated biotissues: fundamentals, equipment, and medical testing

    NASA Astrophysics Data System (ADS)

    Ul'yanov, V. A.; Panchenko, V. Ya.; Geinitz, A. V.; Reshetov, I. V.; Varev, G. A.

    2006-09-01

    New method of Doppler diagnostics based on autodyne effect for diagnostics and control of laser-tissue evaporation by radiation of high-frequency pumped waveguide CO II laser is developed. This method is used for creation of feed-back for smart CO II laser surgical system of "Lancet" series. The results of medical testing of the smart laser surgical system are presented.

  8. 77 FR 3748 - Request for Comments and Notice of Public Hearings on Genetic Diagnostic Testing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-25

    ... Patent and Trademark Office Request for Comments and Notice of Public Hearings on Genetic Diagnostic... in gathering information on the genetic diagnostic testing for purposes of preparing a report on the... USPTO invites the public to provide comments and to attend public hearings addressing genetic...

  9. Identifying Students' Mathematical Skills from a Multiple-Choice Diagnostic Test Using an Iterative Technique to Minimise False Positives

    ERIC Educational Resources Information Center

    Manning, S.; Dix, A.

    2008-01-01

    There is anecdotal evidence that a significant number of students studying computing related courses at degree level have difficulty with sub-GCE mathematics. Testing of students' skills is often performed using diagnostic tests and a number of computer-based diagnostic tests exist, which work, essentially, by testing one specific diagnostic skill…

  10. SMPTE Test Pattern For Certification Of Medical Diagnostic Display Devices

    NASA Astrophysics Data System (ADS)

    Lisk, Kenneth G.

    1984-08-01

    Since the invention of x-rays by Wilhelm Conrad Roentgen, rapid advances have been made in the radiological detection of body abnormalities. This was very evident in the 1960's and 70's when the marriage of computers to radiology gave birth to a new generation of imaging modalities such as computerized tomography, ultrasound, digital radiographic imaging, nuclear medicine, and nuclear magnetic resonance. Many of these devices employ digital computer techniques for signal manipulation, and the resultant analog diagnostic images are displayed on television monitors for viewing and on imaging cathode-ray tubes for a photographic hard copy.

  11. Concordance analysis and diagnostic test accuracy review of IDH1 immunohistochemistry in glioblastoma.

    PubMed

    Pyo, Jung-Soo; Kim, Nae Yu; Kim, Roy Hyun Jai; Kang, Guhyun

    2016-10-01

    The study investigated isocitrate dehydrogenase (IDH) 1 immunohistochemistry (IHC) positive rate and concordance rate between IDH1 IHC and molecular test in glioblastoma. The current study included 1360 glioblastoma cases from sixteen eligible studies. Meta-analysis, including subgroup analysis by antibody clones and cut-off values, for IDH1 IHC positive rate was conducted. In addition, we performed a concordance analysis and diagnostic test accuracy review between IDH1 IHC and molecular tests. The estimated rates of IDH1 IHC were 0.106 [95 % confidence interval (CI) 0.085-0.132]. The IDH1 IHC positive rate of primary and secondary glioblastomas was 0.049 (95 % CI 0.023-0.99) and 0.729 (95 % CI 0.477-0.889), respectively. The overall concordance rate between IDH1 IHC and molecular test was 0.947 (95 % CI 0.878-0.978). In IDH1 IHC-positive and negative subgroups, the concordance rate was 0.842 (95 % CI 0.591-0.952) and 0.982 (95 % CI 0.941-0.995), respectively. The pooled sensitivity and specificity for IDH1 IHC were 1.00 (95 % CI 0.82-1.00) and 0.99 (95 % CI 0.96-1.00), respectively. IDH1 IHC is an accurate test for IDH1 mutation in glioblastoma patients. Further cumulative studies for evaluation criteria of IDH1 IHC will determine how to best apply this approach in daily practice.

  12. Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases

    PubMed Central

    Cantera, Jason L.; Storey, Helen L.; Leader, Brandon T.; de los Santos, Tala

    2016-01-01

    Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test. PMID:28005900

  13. Primary diagnostic approaches of invasive aspergillosis--molecular testing.

    PubMed

    Bretagne, Stéphane

    2011-04-01

    The PCR methods published for the diagnosis of invasive aspergillosis (IA) are diverse in terms of amplification protocols and methods, equipment, fluorescent detection dyes, PCR chemistries, and clinical specimens used. This explains why PCR is still not included in the revised EORTC/MSG definitions of IA despite encouraging results. Therefore, achieving consensual PCR procedures at the international level is mandatory. When using PCR as a diagnostic tool, emphasis must be put on limiting false positive results due to contamination either with previously amplified products or with environmental commensals. Internal amplification controls are compulsory to evidence false negative results. For most of these aspects, quantitative PCR (qPCR) should improve both the results' reliability and the clinicians' confidence. A checklist of items (Minimum information for publication of quantitative real-time PCR experiments) has been proposed to help scientists and reviewers. Currently, the main limitation relies in the DNA extraction procedure the choice of which dramatically depends on the still unknown origin of the Aspergillus DNA to amplify. There is an urgent need for basic studies to elucidate the origin and kinetics of Aspergillus DNA in blood. Once a technical consensus is achieved, clinical studies should be initiated to integrate qPCR in the diagnostic armentarium of IA.

  14. Is Serial Testing Required to Diagnose Imported Malaria in the Era of Rapid Diagnostic Tests?

    PubMed Central

    Pasricha, Janet M.; Juneja, Surender; Manitta, Joseph; Whitehead, Susan; Maxwell, Ellen; Goh, Wai-Keong; Pasricha, Sant-Rayn; Eisen, Damon P.

    2013-01-01

    Exclusion of malaria traditionally requires three negative serial thick and thin blood films. However, many clinical laboratories now routinely perform rapid diagnostic tests (RDTs) in addition to blood films when malaria is suspected. We sought to determine whether serial testing is necessary in this setting. We examined 388 cases of malaria diagnosed during 1999–2010 at three laboratories in Melbourne, Australia. For each case, we ascertained whether the diagnosis was made on initial or follow-up testing. Nine cases (3.5%) were diagnosed after a negative initial blood film and RDT: 7 Plasmodium vivax, 1 P. ovale, and 1 P. falciparum. Of four case-patients with P. vivax in which clinical data were available, all had recent exposure to antimalarial medication. Our data suggest that among patients who have not received recent anti-malarial therapy, and when RDTs are performed and blood films are prepared, most malaria diagnoses are made by using the first set of tests. PMID:23208885

  15. Diagnostic Performance Tests For Elementary Children (Grades 1-4).

    ERIC Educational Resources Information Center

    Hardin, Donald H.; Garcia, Mary Jane

    1982-01-01

    The basic skills of running, jumping, throwing, and ball handling are of primary importance in physical education programs. A battery of four tests and a chart of average performances are presented for testing elementary students. (CJ)

  16. Borehole flowmeter logging for the accurate design and analysis of tracer tests.

    PubMed

    Basiricò, Stefano; Crosta, Giovanni B; Frattini, Paolo; Villa, Alberto; Godio, Alberto

    2015-04-01

    Tracer tests often give ambiguous interpretations that may be due to the erroneous location of sampling points and/or the lack of flow rate measurements through the sampler. To obtain more reliable tracer test results, we propose a methodology that optimizes the design and analysis of tracer tests in a cross borehole mode by using vertical borehole flow rate measurements. Experiments using this approach, herein defined as the Bh-flow tracer test, have been performed by implementing three sequential steps: (1) single-hole flowmeter test, (2) cross-hole flowmeter test, and (3) tracer test. At the experimental site, core logging, pumping tests, and static water-level measurements were previously carried out to determine stratigraphy, fracture characteristics, and bulk hydraulic conductivity. Single-hole flowmeter testing makes it possible to detect the presence of vertical flows as well as inflow and outflow zones, whereas cross-hole flowmeter testing detects the presence of connections along sets of flow conduits or discontinuities intercepted by boreholes. Finally, the specific pathways and rates of groundwater flow through selected flowpaths are determined by tracer testing. We conclude that the combined use of single and cross-borehole flowmeter tests is fundamental to the formulation of the tracer test strategy and interpretation of the tracer test results.

  17. Hereditary red cell membrane disorders and laboratory diagnostic testing.

    PubMed

    King, M-J; Zanella, A

    2013-06-01

    This overview describes two groups of nonimmune hereditary hemolytic anemias caused by defects in membrane proteins located in distinct layers of the red cell membrane. Hereditary spherocytosis (HS), hereditary elliptocytosis (HE), and hereditary pyropoikilocytosis (HPP) represent disorders of the red cell cytoskeleton. Hereditary stomatocytoses represents disorders of cation permeability in the red cell membrane. The current laboratory screening tests for HS are the osmotic fragility test, acid glycerol lysis time test (AGLT), cryohemolysis test, and eosin-5'-maleimide (EMA)-binding test. For atypical HS, SDS-polyacrylamide gel electrophoresis of erythrocyte membrane proteins is carried out to confirm the diagnosis. The diagnosis of HE/HPP is based on abnormal red cell morphology and the detection of protein 4.1R deficiency or spectrin variants using gel electrophoresis. None of screening tests can detect all HS cases. Some testing centers (a survey of 25 laboratories) use a combination of tests (e.g., AGLT and EMA). No specific screening test for hereditary stomatocytoses is available. The preliminary diagnosis is based on presenting a compensated hemolytic anemia, macrocytosis, and a temperature or time dependent pseudohyperkalemia in some patients. Both the EMA-binding test and the osmotic fragility test may help in differential diagnosis of HS and hereditary stomatocytosis.

  18. DNA methylation testing and marker validation using PCR: diagnostic applications.

    PubMed

    Egger, Gerda; Wielscher, Matthias; Pulverer, Walter; Kriegner, Albert; Weinhäusel, Andreas

    2012-01-01

    DNA methylation provides a fundamental epigenetic mechanism to establish and promote cell-specific gene-expression patterns, which are inherited by subsequent cell generations. Thus, the epigenome determines the differentiation into a cell lineage but can also program cells to become abnormal or malignant. In humans, different germline and somatic diseases have been linked to faulty DNA methylation. In this article, we will discuss the available PCR-based technologies to assess differences in DNA methylation levels mainly affecting 5-methylcytosine in the CpG dinucleotide context in hereditary syndromal and somatic pathological conditions. We will discuss some of the current diagnostic applications and provide an outlook on how DNA methylation-based biomarkers might provide novel tools for diagnosis, prognosis or patient stratification for diseases such as cancer.

  19. Development of a Novel, Non-Invasive Diagnostic Test for Prostate Cancer

    DTIC Science & Technology

    2007-01-01

    Invasive Diagnostic Test for Prostate Cancer PRINCIPAL INVESTIGATOR: Robert Gardiner, M.D...Novel, Non-Invasive Diagnostic Test for Prostate Cancer 5b. GRANT NUMBER W81XWH-05-1-0092 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...patients with prostate cancer so that transrectal ultrasound guided biopsies can be restricted to men harboring PCa. Our broad strategy will involve

  20. Testing of optical diagnostics for ion-beam-driven WDM experiments at NDCX-1

    NASA Astrophysics Data System (ADS)

    Ni, P. A.; Bieniosek, F. M.; Leitner, M.; Weber, C.; Waldron, W. L.

    2009-07-01

    We report on the testing of optical diagnostics developed for warm-dense-matter (WDM) experiments on the neutralized drift compression experiments (NDCX-1) at Lawrence Berkeley National Laboratory (LBNL). The diagnostics consists of a fast optical pyrometer, a streak camera spectrometer, and a Doppler-shift laser interferometer (VISAR). While the NDCX is in the last stage of commissioning for the target experiments, the diagnostics were tested elsewhere in an experiment where an intense laser pulse was used to generate the WDM state in metallic and carbon samples.

  1. The robustness of diagnostic tests for GH deficiency in adults.

    PubMed

    Andersen, Marianne

    2015-06-01

    Since the 1970s, GH treatment has been an important tool in paediatric endocrinology for the management of growth retardation. It is now accepted that adults with severe GH deficiency (GHD) demonstrate impaired physical and psychological well-being and may benefit from replacement therapy with recombinant human GH. There is, however, an ongoing debate on how to diagnose GHD, especially in adults. A GH response below the cut-off limit of a GH-stimulation test is required in most cases for establishing GHD in adults. No 'gold standard' GH-stimulation test exists, but some GH stimulation tests may be more robust to variations in patient characteristics such as age and gender, as well as to pre-test conditions like heat exposure due to a hot bath or bicycling. However, body mass index (BMI) is negatively associated with GH-responses to all available GH-stimulation tests and glucocorticoid treatment, including conventional substitution therapy, influences the GH-responses. Recently, the role of IGF-I measurements in the clinical decision making has been discussed. The aim of this review is to discuss the available GH-stimulation tests. In this author's opinion, tests which include growth-hormone-releasing hormone (GHRH) tend to be more potent and robust, especially the GHRH+arginine test which has been proven to be of clinical use. In contrast, the insulin tolerance test (ITT) and the glucagon test appear to have too many drawbacks.

  2. 30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be... 30 Mineral Resources 2 2012-07-01 2012-07-01 false How long do I keep records of casing pressure and diagnostic tests? 250.523 Section 250.523 Mineral Resources BUREAU OF SAFETY AND...

  3. 30 CFR 250.524 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be... 30 Mineral Resources 2 2013-07-01 2013-07-01 false How long do I keep records of casing pressure and diagnostic tests? 250.524 Section 250.524 Mineral Resources BUREAU OF SAFETY AND...

  4. 30 CFR 250.524 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be... 30 Mineral Resources 2 2014-07-01 2014-07-01 false How long do I keep records of casing pressure and diagnostic tests? 250.524 Section 250.524 Mineral Resources BUREAU OF SAFETY AND...

  5. Evaluation of tadpole mouthpart depigmentation as a diagnostic test for infection by Batrachochytrium dendrobatidis for four California anurans.

    PubMed

    Padgett-Flohr, Gretchen E; Goble, Molly E

    2007-10-01

    The objective of this study was to evaluate the utility of gross morphologic examination of larval mouthpart defects as a diagnostic screening test to detect Batrachochytrium dendrobatidis infection in four California, USA, anuran species. We examined mouthparts of 2,034 tadpoles of Bufo boreas, Pseudacris regilla, and Rana catesbeiana collected in 2003 and 2004 and Bufo canorus collected in 2004. Data were recorded for three morphologic features: upper toothrows, lower toothrows, and combined jaw sheaths. Mouthpart defects were observed in all four species (n=757), but only two species were infected with B. dendrobatidis (n=84). Sensitivity and specificity of the mouthparts test were 76% and 58%, respectively. Forty-two percent of B. dendrobatidis-negative animals would have been designated positive based on mouthpart defects. Observed prevalence was 43%, and true prevalence was 3.0%. Tests of the null hypothesis using logistic regression analysis showed that anuran larval mouthpart defects were not associated with B. dendrobatidis infection whether mouthparts scores were tested by individual morphologic feature or in combination (P=0.37). We conclude that B. dendrobatidis infection and anuran larval mouthpart defects are two separate processes that may occur concurrently and that evaluation of tadpole oral morphology is neither an accurate nor a reliable diagnostic test for B. dendrobatidis infection for the four species tested.

  6. [Usefulness of clinical data and rapid diagnostic tests to identify bacterial etiology in adult respiratory infections].

    PubMed

    Toledano-Sierra, Pilar; Arriola-Hernández, Maite; Orueta-Sánchez, Ramón

    2015-01-19

    Respiratory tract infections are a common complaint and most of them, such as common cold and laryngitis, are viral in origin, so antibiotic use should be exceptional. However, there are other respiratory tract infections (sinusitis, pharyngitis, lower respiratory tract infections, and exacerbations of chronic obstructive pulmonary disease) where a bacterial etiology is responsible for a non-negligible percentage, and antibiotics are often empirically indicated. The aim of the study is to identify the strength of the data obtained from the symptoms, physical examination and rapid diagnostic methods in respiratory infections in which antibiotic use is frequently proposed in order to improve diagnosis and influence the decision to prescribe these drugs. The review concludes that history, physical examination and rapid tests are useful to guide the need for antibiotic treatment in diseases such as acute sinusitis, acute pharyngitis, exacerbation of lower respiratory tract infection and chronic obstructive pulmonary disease. However, no isolated data is accurate enough by itself to confirm or rule out the need for antibiotics. Therefore, clinical prediction rules bring together history and physical examination, thereby improving the accuracy of the decision to indicate or not antibiotics.

  7. Statistical tests with accurate size and power for balanced linear mixed models.

    PubMed

    Muller, Keith E; Edwards, Lloyd J; Simpson, Sean L; Taylor, Douglas J

    2007-08-30

    The convenience of linear mixed models for Gaussian data has led to their widespread use. Unfortunately, standard mixed model tests often have greatly inflated test size in small samples. Many applications with correlated outcomes in medical imaging and other fields have simple properties which do not require the generality of a mixed model. Alternately, stating the special cases as a general linear multivariate model allows analysing them with either the univariate or multivariate approach to repeated measures (UNIREP, MULTIREP). Even in small samples, an appropriate UNIREP or MULTIREP test always controls test size and has a good power approximation, in sharp contrast to mixed model tests. Hence, mixed model tests should never be used when one of the UNIREP tests (uncorrected, Huynh-Feldt, Geisser-Greenhouse, Box conservative) or MULTIREP tests (Wilks, Hotelling-Lawley, Roy's, Pillai-Bartlett) apply. Convenient methods give exact power for the uncorrected and Box conservative tests. Simulations demonstrate that new power approximations for all four UNIREP tests eliminate most inaccuracy in existing methods. In turn, free software implements the approximations to give a better choice of sample size. Two repeated measures power analyses illustrate the methods. The examples highlight the advantages of examining the entire response surface of power as a function of sample size, mean differences, and variability.

  8. Auditory Automotive Mechanics Diagnostic Achievement Test. Center Technical Paper No. 2.

    ERIC Educational Resources Information Center

    Swanson, Richard Arthur

    The Auditory Automotive Mechanics Diagnostic Achievement Test assesses an automobile mechanic's ability to determine mechanical faults from auditory cues alone. The 44-item test and its instructions are recorded on magnetic tape; answer choices are presented on tape, and are also written in the printed test booklets. The norming and validity…

  9. Bayesian meta-analysis of diagnostic tests allowing for imperfect reference standards.

    PubMed

    Menten, J; Boelaert, M; Lesaffre, E

    2013-12-30

    There is an increasing interest in meta-analyses of rapid diagnostic tests (RDTs) for infectious diseases. To avoid spectrum bias, these meta-analyses should focus on phase IV studies performed in the target population. For many infectious diseases, these target populations attend primary health care centers in resource-constrained settings where it is difficult to perform gold standard diagnostic tests. As a consequence, phase IV diagnostic studies often use imperfect reference standards, which may result in biased meta-analyses of the diagnostic accuracy of novel RDTs. We extend the standard bivariate model for the meta-analysis of diagnostic studies to correct for differing and imperfect reference standards in the primary studies and to accommodate data from studies that try to overcome the absence of a true gold standard through the use of latent class analysis. Using Bayesian methods, improved estimates of sensitivity and specificity are possible, especially when prior information is available on the diagnostic accuracy of the reference test. In this analysis, the deviance information criterion can be used to detect conflicts between the prior information and observed data. When applying the model to a dataset of the diagnostic accuracy of an RDT for visceral leishmaniasis, the standard meta-analytic methods appeared to underestimate the specificity of the RDT.

  10. Automated tests for diagnosing and monitoring cognitive impairment: a diagnostic accuracy review.

    PubMed Central

    Aslam, Rabeea'h W; Bates, Vickie; Dundar, Yenal; Hounsome, Juliet; Richardson, Marty; Krishan, Ashma; Dickson, Rumona; Boland, Angela; Kotas, Eleanor; Fisher, Joanne; Sikdar, Sudip; Robinson, Louise

    2016-01-01

    BACKGROUND Cognitive impairment is a growing public health concern, and is one of the most distinctive characteristics of all dementias. The timely recognition of dementia syndromes can be beneficial, as some causes of dementia are treatable and are fully or partially reversible. Several automated cognitive assessment tools for assessing mild cognitive impairment (MCI) and early dementia are now available. Proponents of these tests cite as benefits the tests' repeatability and robustness and the saving of clinicians' time. However, the use of these tools to diagnose and/or monitor progressive cognitive impairment or response to treatment has not yet been evaluated. OBJECTIVES The aim of this review was to determine whether or not automated computerised tests could accurately identify patients with progressive cognitive impairment in MCI and dementia and, if so, to investigate their role in monitoring disease progression and/or response to treatment. DATA SOURCES Five electronic databases (MEDLINE, EMBASE, The Cochrane Library, ISI Web of Science and PsycINFO), plus ProQuest, were searched from 2005 to August 2015. The bibliographies of retrieved citations were also examined. Trial and research registers were searched for ongoing studies and reviews. A second search was run to identify individual test costs and acquisition costs for the various tools identified in the review. REVIEW METHODS Two reviewers independently screened all titles and abstracts to identify potentially relevant studies for inclusion in the review. Full-text copies were assessed independently by two reviewers. Data were extracted and assessed for risk of bias by one reviewer and independently checked for accuracy by a second. The results of the data extraction and quality assessment for each study are presented in structured tables and as a narrative summary. RESULTS The electronic searching of databases, including ProQuest, resulted in 13,542 unique citations. The titles and abstracts of these

  11. ACOG Technology Assessment No. 11: Genetics and molecular diagnostic testing.

    PubMed

    2014-02-01

    Human genetics and molecular testing are playing an increasingly important role in medicine, including obstetric and gynecologic practice. As the genetic basis for reproductive disorders, common diseases, and cancer is elucidated with improved molecular technology, genetic testing opportunities are expanding and influencing treatment options and prevention strategies. It is essential that obstetrician-gynecologists be aware of advances in the understanding of genetic disease and the fundamental principles of genetic screening and molecular testing as genetics becomes a more integral part of routine medical practice. This document reviews the basics of genetic transmission and genetic technologies in current use.

  12. EVALUATION OF DIAGNOSTIC ACCURACY OF THE COMPARATIVE TUBERCULIN SKIN TEST IN REHABILITANT BORNEAN ORANGUTANS (PONGO PYGMAEUS).

    PubMed

    Dench, Rosalie; Sulistyo, Fransiska; Fahroni, Agus; Philippa, Joost

    2015-12-01

    The tuberculin skin test (TST) has been the mainstay of tuberculosis (TB) testing in primates for decades, but its interpretation in orangutans (Pongo spp.) is challenging, because many animals react strongly, without evidence of infection with Mycobacterium tuberculosis complex. One explanation is cross-reactivity with environmental nontuberculous mycobacteria (NTM). The use of a comparative TST (CTST), comparing reactivity to avian (representing NTM) and bovine (representing tuberculous mycobacteria) tuberculins aids in distinguishing cross-reactivity due to sensitization by NTM from shared antigens. The specificity of the TST can be increased with the use of CTST. We considered three interpretations of the TST in rehabilitant Bornean orangutans ( Pongo pygmaeus ) using avian purified protein derivative (APPD; 25,000 IU/ml) and two concentrations of bovine purified protein derivative (BPPD; 100,000 and 32,500 IU/ml). The tests were evaluated for their ability to identify accurately seven orangutans previously diagnosed with and treated for TB from a group of presumed negative individuals (n = 288 and n = 161 for the two respective BPPD concentrations). BPPD at 32,500 IU/ml had poor diagnostic capacity, whereas BPPD at 100,000 IU/ml performed better. The BPPD-only interpretation had moderate sensitivity (57%) and poor specificity (40%) and accuracy (41%). The comparative interpretation at 72 hr had similar sensitivity (57%) but improved specificity (95%) and accuracy (94%). However, best results were obtained by a comparative interpretation incorporating the 48- and 72-hr scores, which had good sensitivity (86%), specificity (95%) and accuracy (95%). These data reinforce recommendations that a CTST be used in orangutans and support the use of APPD at 25,000 IU/ml and BPPD at 100,000 IU/ml. The highest score at each site from the 48- and 72-hr checks should be considered the result for that tuberculin. If the bovine result is greater than the avian result, the

  13. FMIT test cell diagnostics3- A unique materials challenge

    NASA Astrophysics Data System (ADS)

    Cannon, C. P.; Fuller, J. L.

    Basic materials problems are discussed in instrumenting the FMIT test cell, which are applicable to fusion devices in general. Recent data on ceramic-to-metal seals, mineral insulated instrument cables, thermocouples, and optical components are reviewed. The data makes it clear that materials and instruments cannot be expected to behave in the FMIT test cell environment as they do in more familiar fission reactors and low power accelerators.

  14. Estimation of diagnostic test accuracy without full verification: a review of latent class methods

    PubMed Central

    Collins, John; Huynh, Minh

    2014-01-01

    The performance of a diagnostic test is best evaluated against a reference test that is without error. For many diseases, this is not possible, and an imperfect reference test must be used. However, diagnostic accuracy estimates may be biased if inaccurately verified status is used as the truth. Statistical models have been developed to handle this situation by treating disease as a latent variable. In this paper, we conduct a systematized review of statistical methods using latent class models for estimating test accuracy and disease prevalence in the absence of complete verification. PMID:24910172

  15. Estimation of diagnostic test accuracy without full verification: a review of latent class methods.

    PubMed

    Collins, John; Huynh, Minh

    2014-10-30

    The performance of a diagnostic test is best evaluated against a reference test that is without error. For many diseases, this is not possible, and an imperfect reference test must be used. However, diagnostic accuracy estimates may be biased if inaccurately verified status is used as the truth. Statistical models have been developed to handle this situation by treating disease as a latent variable. In this paper, we conduct a systematized review of statistical methods using latent class models for estimating test accuracy and disease prevalence in the absence of complete verification.

  16. A Procedure for Accurately Measuring the Shaker Overturning Moment During Random Vibration Tests

    NASA Technical Reports Server (NTRS)

    Nayeri, Reza D.

    2011-01-01

    Motivation: For large system level random vibration tests, there may be some concerns about the shaker's capability for the overturning moment. It is the test conductor's responsibility to predict and monitor the overturning moment during random vibration tests. If the predicted moment is close to the shaker's capability, test conductor must measure the instantaneous moment at low levels and extrapolate to higher levels. That data will be used to decide whether it is safe to proceed to the next test level. Challenge: Kistler analog formulation for computing the real-time moment is only applicable to very limited cases in which we have 3 or 4 load cells installed at shaker interface with hardware. Approach: To overcome that limitation, a simple procedure was developed for computing the overturning moment time histories using the measured time histories of the individual load cells.

  17. Toward an Objective Diagnostic Test for Bacterial Cellulitis

    PubMed Central

    Bry, Lynn; Dwyer, Richard C.; Lipworth, Adam D.; Leung, Donald Y.; Camargo, Carlos A.; Kupper, Thomas S.; Filbin, Michael R.; Murphy, George F.

    2016-01-01

    Background Prior studies repeatedly showed that cultures of skin lesions diagnosed as "cellulitis" are usually negative. However, lack of a gold standard for diagnosis (against which culture might be judged) and failure to assess the human immune response are important limitations of prior work. In this pilot study, we aimed to develop a criterion standard for research on bacterial cellulitis, to evaluate the sensitivity of procalcitonin for bacterial cellulitis, and to use gene expression analysis to find other candidate diagnostic markers. Methods We classified lesions via biopsies, 16s rRNA gene detection, culture, and histopathology. We quantified procalcitonin expression in blood. We also used Nanostring technology to quantify transcription of immunomodulators that may distinguish cases from inflamed controls. Results Of 28 participants, 15 had a clinical diagnosis of cellulitis, six had a diagnosis of non-infectious dermatitis, and seven were normal volunteers. Of the “cellulitis” patients, three (20%) had pathogens isolated, and were designated confirmed cases. Procalcitonin was undetectable in all three. HLA-DQA1 was expressed 34-fold more in confirmed cases vs. controls (fold change of geometric mean). Heat maps depicting multiplex gene expression analysis revealed a distinct profile of gene expression in confirmed cases relative to comparators. Conclusions Most “cellulitis” patients had microbiologically-negative biopsies. Procalcitonin was undetectable, and HLA-DQA1 elevated, in confirmed bacterial cases. Multivariable transcriptomic profiling results supported our algorithm’s ability to identify patients with true bacterial cellulitis. A larger sample may allow discovery of an immunological signature capable of distinguishing bacterial cellulitis from its mimics in clinical practice. PMID:27656884

  18. A Novel Malaria Pf/Pv Ab Rapid Diagnostic Test Using a Differential Diagnostic Marker Identified by Network Biology.

    PubMed

    Cho, Sung Jin; Lee, Jihoo; Lee, Hyun Jae; Jo, Hyun-Young; Sinniah, Mangalam; Kim, Hak-Yong; Chong, Chom-Kyu; Song, Hyun-Ok

    2016-01-01

    Rapid diagnostic tests (RDTs) can detect anti-malaria antibodies in human blood. As they can detect parasite infection at the low parasite density, they are useful in endemic areas where light infection and/or re-infection of parasites are common. Thus, malaria antibody tests can be used for screening bloods in blood banks to prevent transfusion-transmitted malaria (TTM), an emerging problem in malaria endemic areas. However, only a few malaria antibody tests are available in the microwell-based assay format and these are not suitable for field application. A novel malaria antibody (Ab)-based RDT using a differential diagnostic marker for falciparum and vivax malaria was developed as a suitable high-throughput assay that is sensitive and practical for blood screening. The marker, merozoite surface protein 1 (MSP1) was discovered by generation of a Plasmodium-specific network and the hierarchical organization of modularity in the network. Clinical evaluation revealed that the novel Malaria Pf/Pv Ab RDT shows improved sensitivity (98%) and specificity (99.7%) compared with the performance of a commercial kit, SD BioLine Malaria P.f/P.v (95.1% sensitivity and 99.1% specificity). The novel Malaria Pf/Pv Ab RDT has potential for use as a cost-effective blood-screening tool for malaria and in turn, reduces TTM risk in endemic areas.

  19. A Novel Malaria Pf/Pv Ab Rapid Diagnostic Test Using a Differential Diagnostic Marker Identified by Network Biology

    PubMed Central

    Cho, Sung Jin; Lee, Jihoo; Lee, Hyun Jae; Jo, Hyun-Young; Sinniah, Mangalam; Kim, Hak-Yong; Chong, Chom-Kyu; Song, Hyun-Ok

    2016-01-01

    Rapid diagnostic tests (RDTs) can detect anti-malaria antibodies in human blood. As they can detect parasite infection at the low parasite density, they are useful in endemic areas where light infection and/or re-infection of parasites are common. Thus, malaria antibody tests can be used for screening bloods in blood banks to prevent transfusion-transmitted malaria (TTM), an emerging problem in malaria endemic areas. However, only a few malaria antibody tests are available in the microwell-based assay format and these are not suitable for field application. A novel malaria antibody (Ab)-based RDT using a differential diagnostic marker for falciparum and vivax malaria was developed as a suitable high-throughput assay that is sensitive and practical for blood screening. The marker, merozoite surface protein 1 (MSP1) was discovered by generation of a Plasmodium-specific network and the hierarchical organization of modularity in the network. Clinical evaluation revealed that the novel Malaria Pf/Pv Ab RDT shows improved sensitivity (98%) and specificity (99.7%) compared with the performance of a commercial kit, SD BioLine Malaria P.f/P.v (95.1% sensitivity and 99.1% specificity). The novel Malaria Pf/Pv Ab RDT has potential for use as a cost-effective blood-screening tool for malaria and in turn, reduces TTM risk in endemic areas. PMID:27313496

  20. Power calculation for comparing diagnostic accuracies in a multi-reader, multi-test design.

    PubMed

    Kim, Eunhee; Zhang, Zheng; Wang, Youdan; Zeng, Donglin

    2014-12-01

    Receiver operating characteristic (ROC) analysis is widely used to evaluate the performance of diagnostic tests with continuous or ordinal responses. A popular study design for assessing the accuracy of diagnostic tests involves multiple readers interpreting multiple diagnostic test results, called the multi-reader, multi-test design. Although several different approaches to analyzing data from this design exist, few methods have discussed the sample size and power issues. In this article, we develop a power formula to compare the correlated areas under the ROC curves (AUC) in a multi-reader, multi-test design. We present a nonparametric approach to estimate and compare the correlated AUCs by extending DeLong et al.'s (1988, Biometrics 44, 837-845) approach. A power formula is derived based on the asymptotic distribution of the nonparametric AUCs. Simulation studies are conducted to demonstrate the performance of the proposed power formula and an example is provided to illustrate the proposed procedure.

  1. Comprehensive Carrier Screening and Molecular Diagnostic Testing for Recessive Childhood Diseases

    PubMed Central

    Kingsmore, Stephen

    2012-01-01

    Of 7,028 disorders with suspected Mendelian inheritance, 1,139 are recessive and have an established molecular basis. Although individually uncommon, Mendelian diseases collectively account for ~20% of infant mortality and ~18% of pediatric hospitalizations. Molecular diagnostic testing is currently available for only ~300 recessive disorders. Preconception screening, together with genetic counseling of carriers, has resulted in remarkable declines in the incidence of several severe recessive diseases including Tay-Sachs disease and cystic fibrosis. However, extension of preconception screening and molecular diagnostic testing to most recessive disease genes has hitherto been impractical. Recently, we reported a preconception carrier screen / molecular diagnostic test for 448 recessive childhood diseases. The current status of this test is reviewed here. Currently, this reports analytical validity of the comprehensive carrier test. As the clinical validity and clinical utility in the contexts described is ascertained, this article will be updated. PMID:22872815

  2. Improving Building Energy Simulation Programs Through Diagnostic Testing (Fact Sheet)

    SciTech Connect

    Not Available

    2012-02-01

    New test procedure evaluates quality and accuracy of energy analysis tools for the residential building retrofit market. Reducing the energy use of existing homes in the United States offers significant energy-saving opportunities, which can be identified through building simulation software tools that calculate optimal packages of efficiency measures. To improve the accuracy of energy analysis for residential buildings, the National Renewable Energy Laboratory's (NREL) Buildings Research team developed the Building Energy Simulation Test for Existing Homes (BESTEST-EX), a method for diagnosing and correcting errors in building energy audit software and calibration procedures. BESTEST-EX consists of building physics and utility bill calibration test cases, which software developers can use to compare their tools simulation findings to reference results generated with state-of-the-art simulation tools. Overall, the BESTEST-EX methodology: (1) Tests software predictions of retrofit energy savings in existing homes; (2) Ensures building physics calculations and utility bill calibration procedures perform to a minimum standard; and (3) Quantifies impacts of uncertainties in input audit data and occupant behavior. BESTEST-EX is helping software developers identify and correct bugs in their software, as well as develop and test utility bill calibration procedures.

  3. Test system accurately determines tensile properties of irradiated metals at cryogenic temperatures

    NASA Technical Reports Server (NTRS)

    Levine, P. J.; Skalka, R. J.; Vandergrift, E. F.

    1967-01-01

    Modified testing system determines tensile properties of irradiated brittle-type metals at cryogenic temperatures. The system includes a lightweight cryostat, split-screw grips, a universal joint, and a special temperature control system.

  4. Diagnostic development and support of MHD test facilities. Final progress report, March 1980--March 1994

    SciTech Connect

    Not Available

    1995-02-01

    The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU), under U.S. Department of Energy (DOE) Contract No. DE-AC02-80ET-15601, Diagnostic Development and Support of MHD Test Facilities, developed diagnostic instruments for magnetohydrodynamic (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery (HRSR) support, were refined, and new systems to measure temperatures and gas-seed-slag stream characteristics were developed. To further data acquisition and analysis capabilities, the diagnostic systems were interfaced with DIAL`s computers. Technical support was provided for the diagnostic needs of the national MHD research effort. DIAL personnel also cooperated with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs. The initial contract, Testing and Evaluation of Heat Recovery/Seed Recovery, established a data base on heat transfer, slagging effects on heat transfer surfaces, metal durability, secondary combustor performance, secondary combustor design requirements, and other information pertinent to the design of HR/SR components at the Coal-Fired Flow Facility (CFFF). To accomplish these objectives, a combustion test stand was constructed that simulated MHD environments, and mathematical models were developed and evaluated for the heat transfer in hot-wall test sections. Two transitions occurred during the span of this contract. In May 1983, the objectives and title of the contract changed from Testing and Evaluation of Heat Recovery/Seed Recovery to Diagnostic Development and Support of MHD Test Facilities. In July 1988, the research laboratory`s name changed from the MHD Energy Center to the Diagnostic Instrumentation and Analysis Laboratory.

  5. Multiparametric testing of blood protein solutions with diagnostic purpose

    NASA Astrophysics Data System (ADS)

    Alekseev, Sergei G.; Ivanov, Andrei V.; Sviridov, Stanislav V.; Petrova, Galina P.; Petrusevich, Yuriy M.; Boiko, Anna V.; Ten, Dmitry I.

    2005-08-01

    The multiparametric physical method for diagnosis and test of curing cancer diseases based on Rayleigh light scattering is proposed. There was studied simultaneously dynamic and static parameters of blood plasma and serum proteins. A special device for this purpose is described and clinical results are presented.

  6. Cutaneous tuberculosis with nonreactive PPD skin test: a diagnostic challenge*

    PubMed Central

    Nassif, Priscila Wolf; Rosa, Ana Paula Zanatta; Gurgel, Ana Cristina Medeiros; Campanerut, Paula Aline Zanetti; Fillus Neto, José; Cardoso, Rosilene Fressatti

    2015-01-01

    The authors report a case of cutaneous tuberculosis in a 63-year-old female patient, who had an infiltrated, erythematous-ferruginous plaque of indurated aspect on her right leg and a nonreactive PPD skin test. Diagnosis was made by tissue culture and PCR of skin biopsy material. The treatment was performed with pyrazinamide, rifampicin, isoniazid and ethambutol, with good response. PMID:25672314

  7. Patch Test as a Diagnostic Tool in Hand Eczema

    PubMed Central

    Vigneshkarthik, Natarajan; Kuruvila, Sheela

    2016-01-01

    Introduction Allergic contact dermatitis is an important cause of hand eczema. Patch testing is the only investigation available to prove the diagnosis of allergic contact dermatitis. Exposures to allergens differ according to geographical, occupational, economic and social factors. Accordingly, patterns of allergic contact dermatitis differ in different parts of the world and different regions of the same country. Aim To study the causes of allergic contact dermatitis in adult patients with hand eczema with the help of patch testing. Materials and Methods This was a cross-sectional study involving 54 hand eczema patients conducted between October 2013 and June 2015, at a tertiary care centre in Southern India. After a detailed history including history of occupational exposure and detailed examination, patch test was done on these patients with Indian standard series. The patches were removed after 48 hours. Another reading was taken after 72 hours. The readings were interpreted according to International Contact Dermatitis Research Group criteria and noted down. The data were summarized using mean and standard deviation for continuous variables and percentages for categorical and dichotomous variables. The test of association was done with Fisher’s-exact test. Results Hyperkeratotic hand eczema was the commonest morphological type (29%), followed by discoid eczema. Pompholyx was significantly more common among patients with history of atopy. A total of 20 patients (37%) showed patch test positivity to a total of 25 allergens. Nickel was the most common allergen (11.11%) followed by para-phenylenediamine (PPD) (7.4%). Nickel (6 patients) and cobalt (3 patients) were the common allergens among women, while potassium dichromate (3 patients) and parthenium (2 patients) were the common allergens among men. Potassium dichromate allergy was significantly more common among masons and PPD allergy was significantly more common among hair dye users. Discoid pattern of

  8. Diagnostic efficacy of in vitro methods vs. skin testing in patients with inhalant allergies

    SciTech Connect

    Corey, J.P.; Liudahl, J.J.; Young, S.A.; Rodman, S.M. )

    1991-03-01

    The purpose of our study was to investigate the diagnostic efficacy of two selected methods of in vitro allergy testing. Specifically, the PRIST/modified RAST I125 isotope systems and the Quantizyme/modified EAST alkaline phosphatase method were compared. The time, expense, convenience, and diagnostic efficacy of the two procedures are discussed. Special attention is given to the practicality of each method for the practicing physician.

  9. Accurate testing of aspheric surfaces using the transport of intensity equation by properly selecting the defocusing distance.

    PubMed

    Soltani, Peyman; Darudi, Ahmad; Nehmetallah, George; Moradi, Ali Reza; Amiri, Javad

    2016-12-10

    In the last decade, the transport of intensity has been increasingly used in microscopy, wavefront sensing, and metrology. In this study, we verify by simulation and experiment the use of the transport of intensity equation (TIE) in the accurate testing of optical aspheric surfaces. Guided by simulation results and assuming that the experimental setup parameters and the conic constants are known, one can estimate an appropriate defocusing distance Δz that leads to an accurate solution of the TIE. In this paper, this method is verified through the construction of a non-nulled experiment for testing the 2D profile of an aspheric surface. The theoretical method and experimental results are compared to validate the results. Finally, to validate the TIE methodology, the phase distribution obtained by TIE is compared with the phase distribution obtained by a Shack-Hartmann sensor.

  10. Comparative evaluation of two rapid field tests for malaria diagnosis: Partec Rapid Malaria Test® and Binax Now® Malaria Rapid Diagnostic Test

    PubMed Central

    2011-01-01

    Background About 90% of all malaria deaths in sub-Saharan Africa occur in children under five years. Fast and reliable diagnosis of malaria requires confirmation of the presence of malaria parasites in the blood of patients with fever or history suggestive of malaria; hence a prompt and accurate diagnosis of malaria is the key to effective disease management. Confirmation of malaria infection requires the availability of a rapid, sensitive, and specific testing at an affordable cost. We compared two recent methods (the novel Partec Rapid Malaria Test® (PT) and the Binax Now® Malaria Rapid Diagnostic Test (BN RDT) with the conventional Giemsa stain microscopy (GM) for the diagnosis of malaria among children in a clinical laboratory of a hospital in a rural endemic area of Ghana. Methods Blood samples were collected from 263 children admitted with fever or a history of fever to the pediatric clinic of the Agogo Presbyterian Hospital. The three different test methods PT, BN RDT and GM were performed independently by well trained and competent laboratory staff to assess the presence of malaria parasites. Results were analyzed and compared using GM as the reference standard. Results In 107 (40.7%) of 263 study participants, Plasmodium sp. was detected by GM. PT and BN RDT showed positive results in 111 (42.2%) and 114 (43.4%), respectively. Compared to GM reference standard, the sensitivities of the PT and BN RDT were 100% (95% CI: 96.6-100) and 97.2% (95% CI: 92.0-99.4), respectively, specificities were 97.4% (95% CI: 93.6-99.3) and 93.6% (95% CI: 88.5-96.9), respectively. There was a strong agreement (kappa) between the applied test methods (GM vs PT: 0.97; p < 0.001 and GM vs BN RDT: 0.90; p < 0.001). The average turnaround time per tests was 17 minutes. Conclusion In this study two rapid malaria tests, PT and BN RDT, demonstrated a good quality of their performance compared to conventional GM. Both methods require little training, have short turnaround times, are

  11. [The diagnostic value of tests for mental control].

    PubMed

    Lindeboom, J; Koene, T; Matto, D

    1993-06-01

    Designated as Mental Control, the recitation of word lists and arithmetic progressions is often used for a cursory examination of attention and concentration in elderly patients. We studied the psychometric properties of the EMCT (Expanded Mental Control Test), which consists of 12 mental control tasks. The test was given to 174 residents of rest homes and semi-independent housing projects (aged 68 to 94) and 74 neurologic patients (aged 65 to 87) who had been referred for neuropsychological assessment. The reliability of the EMCT was satisfactory. Performance was related to education level but not to sex or age. In healthy subjects the EMCT score was associated with the backward digit span score. The correlations between the EMCT and subtests of the Amsterdam Dementia Screening (Ads6) in patients appeared to depend on the complexity of the target behavior. Performance on the EMCT may reflect the functioning of the Supervisory Attentional System postulated by Shallice.

  12. Diagnostic Role of ECG Recording Simultaneously With EEG Testing.

    PubMed

    Kendirli, Mustafa Tansel; Aparci, Mustafa; Kendirli, Nurten; Tekeli, Hakan; Karaoglan, Mustafa; Senol, Mehmet Guney; Togrol, Erdem

    2015-07-01

    Arrhythmia is not uncommon in the etiology of syncope which mimics epilepsy. Data about the epilepsy induced vagal tonus abnormalities have being increasingly reported. So we aimed to evaluate what a neurologist may gain by a simultaneous electrocardiogram (ECG) and electroencephalogram (EEG) recording in the patients who underwent EEG testing due to prediagnosis of epilepsy. We retrospectively evaluated and detected ECG abnormalities in 68 (18%) of 376 patients who underwent EEG testing. A minimum of 20 of minutes artifact-free recording were required for each patient. Standard 1-channel ECG was simultaneously recorded in conjunction with the EEG. In all, 28% of females and 14% of males had ECG abnormalities. Females (mean age 49 years, range 18-88 years) were older compared with the male group (mean age 28 years, range 16-83 years). Atrial fibrillation was more frequent in female group whereas bradycardia and respiratory sinus arrhythmia was higher in male group. One case had been detected a critical asystole indicating sick sinus syndrome in the female group and treated with a pacemaker implantation in the following period. Simultaneous ECG recording in conjunction with EEG testing is a clinical prerequisite to detect and to clarify the coexisting ECG and EEG abnormalities and their clinical relevance. Potentially rare lethal causes of syncope that mimic seizure or those that could cause resistance to antiepileptic therapy could effectively be distinguished by detecting ECG abnormalities coinciding with the signs and abnormalities during EEG recording.

  13. Chromosomal microarray analysis as a first-tier clinical diagnostic test: Estonian experience.

    PubMed

    Zilina, Olga; Teek, Rita; Tammur, Pille; Kuuse, Kati; Yakoreva, Maria; Vaidla, Eve; Mölter-Väär, Triin; Reimand, Tiia; Kurg, Ants; Ounap, Katrin

    2014-03-01

    Chromosomal microarray analysis (CMA) is now established as the first-tier cytogenetic diagnostic test for fast and accurate detection of chromosomal abnormalities in patients with developmental delay/intellectual disability (DD/ID), multiple congenital anomalies (MCA), and autism spectrum disorders (ASD). We present our experience with using CMA for postnatal and prenatal diagnosis in Estonian patients during 2009-2012. Since 2011, CMA is on the official service list of the Estonian Health Insurance Fund and is performed as the first-tier cytogenetic test for patients with DD/ID, MCA or ASD. A total of 1191 patients were analyzed, including postnatal (1072 [90%] patients and 59 [5%] family members) and prenatal referrals (60 [5%] fetuses). Abnormal results were reported in 298 (25%) patients, with a total of 351 findings (1-3 per individual): 147 (42%) deletions, 106 (30%) duplications, 89 (25%) long contiguous stretches of homozygosity (LCSH) events (>5 Mb), and nine (3%) aneuploidies. Of all findings, 143 (41%) were defined as pathogenic or likely pathogenic; for another 143 findings (41%), most of which were LCSH, the clinical significance remained unknown, while 61 (18%) reported findings can now be reclassified as benign or likely benign. Clinically relevant findings were detected in 126 (11%) patients. However, the proportion of variants of unknown clinical significance was quite high (41% of all findings). It seems that our ability to detect chromosomal abnormalities has far outpaced our ability to understand their role in disease. Thus, the interpretation of CMA findings remains a rather difficult task requiring a close collaboration between clinicians and cytogeneticists.

  14. Chromosomal microarray analysis as a first-tier clinical diagnostic test: Estonian experience

    PubMed Central

    Žilina, Olga; Teek, Rita; Tammur, Pille; Kuuse, Kati; Yakoreva, Maria; Vaidla, Eve; Mölter-Väär, Triin; Reimand, Tiia; Kurg, Ants; Õunap, Katrin

    2014-01-01

    Chromosomal microarray analysis (CMA) is now established as the first-tier cytogenetic diagnostic test for fast and accurate detection of chromosomal abnormalities in patients with developmental delay/intellectual disability (DD/ID), multiple congenital anomalies (MCA), and autism spectrum disorders (ASD). We present our experience with using CMA for postnatal and prenatal diagnosis in Estonian patients during 2009–2012. Since 2011, CMA is on the official service list of the Estonian Health Insurance Fund and is performed as the first-tier cytogenetic test for patients with DD/ID, MCA or ASD. A total of 1191 patients were analyzed, including postnatal (1072 [90%] patients and 59 [5%] family members) and prenatal referrals (60 [5%] fetuses). Abnormal results were reported in 298 (25%) patients, with a total of 351 findings (1–3 per individual): 147 (42%) deletions, 106 (30%) duplications, 89 (25%) long contiguous stretches of homozygosity (LCSH) events (>5 Mb), and nine (3%) aneuploidies. Of all findings, 143 (41%) were defined as pathogenic or likely pathogenic; for another 143 findings (41%), most of which were LCSH, the clinical significance remained unknown, while 61 (18%) reported findings can now be reclassified as benign or likely benign. Clinically relevant findings were detected in 126 (11%) patients. However, the proportion of variants of unknown clinical significance was quite high (41% of all findings). It seems that our ability to detect chromosomal abnormalities has far outpaced our ability to understand their role in disease. Thus, the interpretation of CMA findings remains a rather difficult task requiring a close collaboration between clinicians and cytogeneticists. PMID:24689080

  15. [Implication of laparoscopy in diagnostics of genital tb among women through cytohistological testing of bioptic specimen].

    PubMed

    Lortkipanidze, G G; Vashakidze, L M; Mamaladze, T T; Gudzhabidze, N B

    2015-01-01

    Diagnostics of genital TB among women is a serious challenge because of the absence of specific clinical manifestation and difficulty to obtain material for bacteriological verification of the pathogen. All the cases with ascites and masses in pelvic cavity must undergo thorough testing to exclude tuberculosis. The present article describes 14 suspect cases of genital TB, where along with the mandatory clinical diagnostic studies (including PCR of ascites and bacteriological testing for TB, also on carcinoma of CA-125 ovary) they have conducted laparoscopy, with further cytological and bacteriological testing of bioptic sample. This method allowed us to diagnose genital and abdominal tuberculosis among women in 85,7% of cases through cytologic and histologic testing and to exclude ovarian carcinoma. Effectiveness of laparoscopy has been confirmed in diagnostics of genital and abdominal TB.

  16. Qualitative study of how women define and use information about breast symptoms and diagnostic tests.

    PubMed

    Davey, Heather M; Butow, Phyllis N

    2006-10-01

    Unstructured interviews were conducted with 14 women with recent experience of diagnostic testing to explore the definition and role of information in women's experiences of undergoing diagnostic breast tests. Analysis showed that women see information as more than what they are told by healthcare professionals. Information also comes from significant others, administration and reception staff, media, comparison with previous breast symptoms, silences, gestures and behavior of healthcare professionals and significant others, and the number of tests they undergo. Information is about more than understanding. It can provide support and control, reduce anxiety, facilitate question asking and promote women's trust and confidence in themselves and their healthcare professionals. Healthcare professionals need to be aware that women define information more broadly than what they are told, and of the importance women attach to this other information. They also need to be aware that information serves more purposes than helping women understand the diagnostic testing process and their result.

  17. The diagnostic accuracy of the Kemp’s test: a systematic review

    PubMed Central

    Stuber, Kent; Lerede, Caterina; Kristmanson, Kevyn; Sajko, Sandy; Bruno, Paul

    2014-01-01

    Background: The objective of this review was to evaluate the existing literature regarding the accuracy of the Kemp’s test in the diagnosis of facet joint pain compared to a reference standard. Methods: Several databases were searched. All diagnostic accuracy studies comparing the Kemp’s test with an acceptable reference standard were included. Included studies were scored for quality and internal validity. Results: Five articles met the inclusion criteria of this review. Two studies had a low risk of bias, and three had a low concern regarding applicability. Pooling of data from studies using similar methods revealed that the test’s negative predictive value was the only diagnostic accuracy measure above 50% (56.8%, 59.9%). Conclusions: Currently, the literature supporting the use of the Kemp’s test is limited and indicates that it has poor diagnostic accuracy. It is debatable whether clinicians should continue to use this test to diagnose facet joint pain. PMID:25202153

  18. Diagnostic mistakes of culturally diverse individuals when using North American neuropsychological tests.

    PubMed

    Daugherty, Julia C; Puente, Antonio E; Fasfous, Ahmed F; Hidalgo-Ruzzante, Natalia; Pérez-Garcia, Miguel

    2017-01-01

    Although the role of culture has increasingly gained acceptance in clinical neuropsychology, relatively minimal research exists regarding the actual impact on clinical activities. In this study, we assess how using North American neuropsychological tests affects diagnostic accuracy in cognitive disorders of culturally diverse individuals. To address this question, participants from Colombia, Morocco, and Spain were administered five commonly used neuropsychological tests and the test results were used to determine whether they would be classified as having the DSM-5 diagnostic criteria for Mild Cognitive and Major Cognitive Disorder. Results reveal that diagnostic error occurred up to 20% of the time, and that the frequency of misdiagnosis differed by nationality. These results provide evidence that using tests from one culture to assess individuals from other cultures produces significant false positives. Findings are discussed in terms of the foundations of neuropsychological assessment and its relationship to cultural variables.

  19. Molecular diagnostics: harmonization through reference materials, documentary standards and proficiency testing.

    PubMed

    Holden, Marcia J; Madej, Roberta M; Minor, Philip; Kalman, Lisa V

    2011-09-01

    There is a great need for harmonization in nucleic acid testing for infectious disease and clinical genetics. The proliferation of assay methods, the number of targets for molecular diagnostics and the absence of standard reference materials contribute to variability in test results among laboratories. This article provides a comprehensive overview of reference materials, related documentary standards and proficiency testing programs. The article explores the relationships among these resources and provides necessary information for people practicing in this area that is not taught in formal courses and frequently is obtained on an ad hoc basis. The aim of this article is to provide helpful tools for molecular diagnostic laboratories.

  20. Defining the next generation of Plasmodium vivax diagnostic tests for control and elimination: Target product profiles.

    PubMed

    Ding, Xavier C; Ade, Maria Paz; Baird, J Kevin; Cheng, Qin; Cunningham, Jane; Dhorda, Mehul; Drakeley, Chris; Felger, Ingrid; Gamboa, Dionicia; Harbers, Matthias; Herrera, Socrates; Lucchi, Naomi; Mayor, Alfredo; Mueller, Ivo; Sattabongkot, Jetsumon; Ratsimbason, Arsène; Richards, Jack; Tanner, Marcel; González, Iveth J

    2017-04-03

    The global prevalence of malaria has decreased over the past fifteen years, but similar gains have not been realized against Plasmodium vivax because this species is less responsive to conventional malaria control interventions aimed principally at P. falciparum. Approximately half of all malaria cases outside of Africa are caused by P. vivax. This species places dormant forms in human liver that cause repeated clinical attacks without involving another mosquito bite. The diagnosis of acute patent P. vivax malaria relies primarily on light microscopy. Specific rapid diagnostic tests exist but typically perform relatively poorly compared to those for P. falciparum. Better diagnostic tests are needed for P. vivax. To guide their development, FIND, in collaboration with P. vivax experts, identified the specific diagnostic needs associated with this species and defined a series of three distinct target product profiles, each aimed at a particular diagnostic application: (i) point-of-care of acutely ill patients for clinical care purposes; (ii) point-of-care asymptomatic and otherwise sub-patent residents for public health purposes, e.g., mass screen and treat campaigns; and (iii) ultra-sensitive not point-of-care diagnosis for epidemiological research/surveillance purposes. This report presents and discusses the rationale for these P. vivax-specific diagnostic target product profiles. These contribute to the rational development of fit-for-purpose diagnostic tests suitable for use the clinical management, control and elimination of P. vivax malaria.

  1. The use of experimental bending tests to more accurate numerical description of TBC damage process

    NASA Astrophysics Data System (ADS)

    Sadowski, T.; Golewski, P.

    2016-04-01

    Thermal barrier coatings (TBCs) have been extensively used in aircraft engines to protect critical engine parts such as blades and combustion chambers, which are exposed to high temperatures and corrosive environment. The blades of turbine engines are additionally exposed to high mechanical loads. These loads are created by the high rotational speed of the rotor (30 000 rot/min), causing the tensile and bending stresses. Therefore, experimental testing of coated samples is necessary in order to determine strength properties of TBCs. Beam samples with dimensions 50×10×2 mm were used in those studies. The TBC system consisted of 150 μm thick bond coat (NiCoCrAlY) and 300 μm thick top coat (YSZ) made by APS (air plasma spray) process. Samples were tested by three-point bending test with various loads. After bending tests, the samples were subjected to microscopic observation to determine the quantity of cracks and their depth. The above mentioned results were used to build numerical model and calibrate material data in Abaqus program. Brittle cracking damage model was applied for the TBC layer, which allows to remove elements after reaching criterion. Surface based cohesive behavior was used to model the delamination which may occur at the boundary between bond coat and top coat.

  2. Revisiting the blind tests in crystal structure prediction: accurate energy ranking of molecular crystals.

    PubMed

    Asmadi, Aldi; Neumann, Marcus A; Kendrick, John; Girard, Pascale; Perrin, Marc-Antoine; Leusen, Frank J J

    2009-12-24

    In the 2007 blind test of crystal structure prediction hosted by the Cambridge Crystallographic Data Centre (CCDC), a hybrid DFT/MM method correctly ranked each of the four experimental structures as having the lowest lattice energy of all the crystal structures predicted for each molecule. The work presented here further validates this hybrid method by optimizing the crystal structures (experimental and submitted) of the first three CCDC blind tests held in 1999, 2001, and 2004. Except for the crystal structures of compound IX, all structures were reminimized and ranked according to their lattice energies. The hybrid method computes the lattice energy of a crystal structure as the sum of the DFT total energy and a van der Waals (dispersion) energy correction. Considering all four blind tests, the crystal structure with the lowest lattice energy corresponds to the experimentally observed structure for 12 out of 14 molecules. Moreover, good geometrical agreement is observed between the structures determined by the hybrid method and those measured experimentally. In comparison with the correct submissions made by the blind test participants, all hybrid optimized crystal structures (apart from compound II) have the smallest calculated root mean squared deviations from the experimentally observed structures. It is predicted that a new polymorph of compound V exists under pressure.

  3. MULTICORR: A Computer Program for Fast, Accurate, Small-Sample Testing of Correlational Pattern Hypotheses.

    ERIC Educational Resources Information Center

    Steiger, James H.

    1979-01-01

    The program presented computes a chi-square statistic for testing pattern hypotheses on correlation matrices. The statistic is based on a multivariate generalization of the Fisher r-to-z transformation. This statistic has small sample performance which is superior to an analogous likelihood ratio statistic obtained via the analysis of covariance…

  4. Paradoxical Effects of Testing: Retrieval Enhances Both Accurate Recall and Suggestibility in Eyewitnesses

    ERIC Educational Resources Information Center

    Chan, Jason C. K.; Langley, Moses M.

    2011-01-01

    Although retrieval practice typically enhances memory retention, it can also impair subsequent eyewitness memory accuracy (Chan, Thomas, & Bulevich, 2009). Specifically, participants who had taken an initial test about a witnessed event were more likely than nontested participants to recall subsequently encountered misinformation--an effect we…

  5. More Than Just Accuracy: A Novel Method to Incorporate Multiple Test Attributes in Evaluating Diagnostic Tests Including Point of Care Tests

    PubMed Central

    Weigl, Bernhard; Fitzpatrick, Annette; Ide, Nicole

    2016-01-01

    Current frameworks for evaluating diagnostic tests are constrained by a focus on diagnostic accuracy, and assume that all aspects of the testing process and test attributes are discrete and equally important. Determining the balance between the benefits and harms associated with new or existing tests has been overlooked. Yet, this is critically important information for stakeholders involved in developing, testing, and implementing tests. This is particularly important for point of care tests (POCTs) where tradeoffs exist between numerous aspects of the testing process and test attributes. We developed a new model that multiple stakeholders (e.g., clinicians, patients, researchers, test developers, industry, regulators, and health care funders) can use to visualize the multiple attributes of tests, the interactions that occur between these attributes, and their impacts on health outcomes. We use multiple examples to illustrate interactions between test attributes (test availability, test experience, and test results) and outcomes, including several POCTs. The model could be used to prioritize research and development efforts, and inform regulatory submissions for new diagnostics. It could potentially provide a way to incorporate the relative weights that various subgroups or clinical settings might place on different test attributes. Our model provides a novel way that multiple stakeholders can use to visualize test attributes, their interactions, and impacts on individual and population outcomes. We anticipate that this will facilitate more informed decision making around diagnostic tests. PMID:27574576

  6. A Comparison of the Minnesota Perceptual Diagnostic Test Revised and the Bender Gestalt.

    ERIC Educational Resources Information Center

    Vance, Booney; And Others

    1986-01-01

    The study involving 33 children referred to school psychologists compared the Bender Gestalt and the Minnesota Perceptual Diagnostic Test-Revised (MPDT-R) in ability to predict intellectual and academic performance as measured by standardized tests. Factor analysis suggested that the MPDT-R provides unique information concerning…

  7. The Application of the Monte Carlo Approach to Cognitive Diagnostic Computerized Adaptive Testing With Content Constraints

    ERIC Educational Resources Information Center

    Mao, Xiuzhen; Xin, Tao

    2013-01-01

    The Monte Carlo approach which has previously been implemented in traditional computerized adaptive testing (CAT) is applied here to cognitive diagnostic CAT to test the ability of this approach to address multiple content constraints. The performance of the Monte Carlo approach is compared with the performance of the modified maximum global…

  8. Constructing and Validating a Q-Matrix for Cognitive Diagnostic Analyses of a Reading Test

    ERIC Educational Resources Information Center

    Li, Hongli; Suen, Hoi K.

    2013-01-01

    Cognitive diagnostic analyses have been advocated as methods that allow an assessment to function as a formative assessment to inform instruction. To use this approach, it is necessary to first identify the skills required for each item in the test, known as a Q-matrix. However, because the construct being tested and the underlying cognitive…

  9. The Impact of Time-Series Diagnostic Tests on the Writing Ability of Iranian EFL Learners

    ERIC Educational Resources Information Center

    Atashgahi, Bahareh Molazem

    2014-01-01

    This study aimed to show whether administering a battery of time-series diagnostic tests (screening) has any impact on Iranian EFL learners' writing ability. The study was conducted on the intermediate EFL learners at Islamic Azad University North Tehran branch. The researcher administered a homogenizing test in order to exclude the exceptional…

  10. Diagnostic Tests and Criterion-Referenced Assessments: Their Contribution to the Resolution of Pupil Learning Difficulties.

    ERIC Educational Resources Information Center

    Simpson, Mary; Arnold, Brian

    1983-01-01

    Suggests that failure to learn is often the result of inappropriateness of level of instruction and deficiencies in instructional procedures and educational strategies, and differentiates between the functions of criterion referenced tests and diagnostic tests. Results are reported from two studies of the teaching of osmosis and photosynthesis.…

  11. Development and Use of Diagnostic Tests to Evaluate Students' Misconceptions in Science.

    ERIC Educational Resources Information Center

    Treagust, David F.

    1988-01-01

    Describes 10 steps for developing a diagnostic test of students' misconceptions and the use of two tests in chemistry (covalent bonding and structure) and in biology (photosynthesis and respiration in plants). Discusses the results and some implications for teaching science. (YP)

  12. Cognitive Diagnostic Models for Tests with Multiple-Choice and Constructed-Response Items

    ERIC Educational Resources Information Center

    Kuo, Bor-Chen; Chen, Chun-Hua; Yang, Chih-Wei; Mok, Magdalena Mo Ching

    2016-01-01

    Traditionally, teachers evaluate students' abilities via their total test scores. Recently, cognitive diagnostic models (CDMs) have begun to provide information about the presence or absence of students' skills or misconceptions. Nevertheless, CDMs are typically applied to tests with multiple-choice (MC) items, which provide less diagnostic…

  13. Development and Validation of a Diagnostic Grammar Test for Japanese Learners of English

    ERIC Educational Resources Information Center

    Koizumi, Rie; Sakai, Hideki; Ido, Takahiro; Ota, Hiroshi; Hayama, Megumi; Sato, Masatoshi; Nemoto, Akiko

    2011-01-01

    This article reports on the development and validation of the English Diagnostic Test of Grammar (EDiT Grammar) for Japanese learners of English. From among the many aspects of grammar, this test focuses on the knowledge of basic English noun phrases (NPs), especially their internal structures, because previous research has indicated the…

  14. 30 CFR 250.520 - When do I have to perform a casing diagnostic test?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... test? 250.520 Section 250.520 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... SHELF Oil and Gas Well-Completion Operations Casing Pressure Management § 250.520 When do I have to... a casing diagnostic test if * * * (1) fixed platform well, the casing pressure is greater than...

  15. Accurate assessment of work done and power during a Wingate anaerobic test.

    PubMed

    Franklin, Kathryn L; Gordon, Rae S; Baker, Julien S; Davies, Bruce

    2007-04-01

    A Monark cycle ergometer is used in physiological studies to measure work done and power. In this paper, the accuracy of a Monark rope-braked cycle ergometer was examined for a Wingate anaerobic test (WAnT). The traditional method of determining brake torque fails to take into account rope-brake theory and, as the brake torque is used to determine the moment of inertia of the flywheel, a second error is introduced into the calculation to determine the work done or power. In this study, the rope tensions were measured to determine the actual brake torque. A deceleration test was carried out to determine the moment of inertia of the system. The work done by subjects of different masses was calculated for various accelerations and it was found that the traditional calculations overestimate work done and power by between 12% and 14.7%.

  16. A guide to properly select the defocusing distance for accurate solution of transport of intensity equation while testing aspheric surfaces

    NASA Astrophysics Data System (ADS)

    Soltani, Peyman; Darudi, Ahmad; Moradi, Ali Reza; Amiri, Javad; Nehmetallah, Georges

    2016-05-01

    In this paper, the Transport of Intensity Equation (TIE) for testing of an aspheric surface is verified experimentally. Using simulation, a proper defocus distance Δ𝑧 that leads to an accurate solution of TIE is estimated whenever the conic constant and configuration of the experiment are known. To verify this procedure a non-nulled experiment for testing an aspheric is used. For verification of the solution, the results are compared with the Shack-Hartmann sensor. The theoretical method and experimental results are compared to validate the results.

  17. Temperature as a diagnostic for the drift scale test

    SciTech Connect

    Lin, W; Wagoner, J; Ballard, S

    2000-10-31

    The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, the radioactive decay heat released from high-level nuclear waste will heat up the rock mass. The heat will mobilize pore water in the rock mass by evaporation, and even boiling, if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam may flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and fracture network will control the drainage of the condensed water. Some of the water may flow back toward the waste package and reevaporated. This thermal-hydrological (TH) process will affect the amount of water that may come into contact with the waste package. Water is the main concern for the integrity of the waste package and the waste form, and the potential transport of radioactive nuclides. Thermally driven chemical and mechanical processes may affect the TH process. The coupled thermal-hydrological-mechanical-chemical (THMC) processes need to be understood before the performance of a repository can be adequately predicted. DOE is conducting field thermal tests to provide data for validating the model of the coupled THMC processes. Therefore, understanding the processes revealed by a field thermal test is essential for the model validation. This paper presents examples that temperature measurement is an effective tool for understanding the TH process.

  18. Diagnostic performance characteristics of a rapid field test for anthrax in cattle.

    PubMed

    Muller, Janine; Gwozdz, Jacek; Hodgeman, Rachel; Ainsworth, Catherine; Kluver, Patrick; Czarnecki, Jill; Warner, Simone; Fegan, Mark

    2015-07-01

    Although diagnosis of anthrax can be made in the field with a peripheral blood smear, and in the laboratory with bacterial culture or molecular based tests, these tests require either considerable experience or specialised equipment. Here we report on the evaluation of the diagnostic sensitivity and specificity of a simple and rapid in-field diagnostic test for anthrax, the anthrax immunochromatographic test (AICT). The AICT detects the protective antigen (PA) component of the anthrax toxin present within the blood of an animal that has died from anthrax. The test provides a result in 15min and offers the advantage of avoiding the necessity for on-site necropsy and subsequent occupational risks and environmental contamination. The specificity of the test was determined by testing samples taken from 622 animals, not infected with Bacillus anthracis. Diagnostic sensitivity was estimated on samples taken from 58 animals, naturally infected with B. anthracis collected over a 10-year period. All samples used to estimate the diagnostic sensitivity and specificity of the AICT were also tested using the gold standard of bacterial culture. The diagnostic specificity of the test was estimated to be 100% (99.4-100%; 95% CI) and the diagnostic sensitivity was estimated to be 93.1% (83.3-98.1%; 95% CI) (Clopper-Pearson method). Four samples produced false negative AICT results. These were among 9 samples, all of which tested positive for B. anthracis by culture, where there was a time delay between collection and testing of >48h and/or the samples were collected from animals that were >48h post-mortem. A statistically significant difference (P<0.001; Fishers exact test) was found between the ability of the AICT to detect PA in samples from culture positive animals <48h post-mortem, 49 of 49, Se=100% (92.8-100%; 95% CI) compared with samples tested >48h post-mortem 5 of 9 Se=56% (21-86.3%; 95% CI) (Clopper-Pearson method). Based upon these results a post hoc cut-off for use of

  19. Diffusion of molecular diagnostic lung cancer tests: a survey of german oncologists.

    PubMed

    Steffen, Julius Alexander

    2014-03-21

    This study was aimed at examining the diffusion of diagnostic lung cancer tests in Germany. It was motivated by the high potential of detecting and targeting oncogenic drivers. Recognizing that the diffusion of diagnostic tests is a conditio sine qua non for the success of personalized lung cancer therapies, this study analyzed the diffusion of epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tests in Germany. Qualitative and quantitative research strategies were combined in a mixed-method design. A literature review and subsequent Key Opinion Leader interviews identified a set of qualitative factors driving the diffusion process, which were then translated into an online survey. The survey was conducted among a sample of 961 oncologists (11.34% response rate). The responses were analyzed in a multiple linear regression which identified six statistically significant factors driving the diffusion of molecular diagnostic lung cancer tests: reimbursement, attitude towards R&D, information self-assessment, perceived attitudes of colleagues, age and test-pathway strategies. Besides the important role of adequate reimbursement and relevant guidelines, the results of this study suggest that an increasing usage of test-pathway strategies, especially in an office-based setting, can increase the diffusion of molecular diagnostic lung cancer tests in the future.

  20. Evaluation of delayed puberty: what diagnostic tests should be performed in the seemingly otherwise well adolescent?

    PubMed

    Abitbol, Leah; Zborovski, Stephen; Palmert, Mark R

    2016-08-01

    Delayed puberty (DP) is defined as the lack of pubertal development by an age that is 2-2.5 SDs beyond the population mean. Although it generally represents a normal variant in pubertal timing, concern that DP could be the initial presentation of a serious underlying disorder has led to a diagnostic approach that is variable and may include tests that are unnecessary and costly. In this review, we examine available literature regarding the recommended diagnostic tests and aetiologies identified during the evaluation of youth with DP. We view this literature through the prism of the seemingly otherwise well adolescent. To provide further clinical context, we also evaluate the clinical and laboratory data from patients seen with DP in our centre over a 2-year period. The literature and our data reveal wide variability in the number of tests performed and raise the question of whether tests, other than gonadotropins, obtained in the absence of signs or symptoms of an underlying disorder are routinely warranted. Together this information provides a pragmatic rationale for revisiting recommendations calling for broad testing during the initial diagnostic evaluation of an otherwise healthy adolescent with DP. We highlight the need for further research comparing the utility of broader screening with a more streamlined approach, such as limiting initial testing to gonadotropins and a bone age, which, while not diagnostic, is often useful for height prediction, followed by close clinical monitoring. If future research supports a more streamlined approach to DP, then much unnecessary testing could be eliminated.

  1. Accurate time delay technology in simulated test for high precision laser range finder

    NASA Astrophysics Data System (ADS)

    Chen, Zhibin; Xiao, Wenjian; Wang, Weiming; Xue, Mingxi

    2015-10-01

    With the continuous development of technology, the ranging accuracy of pulsed laser range finder (LRF) is higher and higher, so the maintenance demand of LRF is also rising. According to the dominant ideology of "time analog spatial distance" in simulated test for pulsed range finder, the key of distance simulation precision lies in the adjustable time delay. By analyzing and comparing the advantages and disadvantages of fiber and circuit delay, a method was proposed to improve the accuracy of the circuit delay without increasing the count frequency of the circuit. A high precision controllable delay circuit was designed by combining the internal delay circuit and external delay circuit which could compensate the delay error in real time. And then the circuit delay accuracy could be increased. The accuracy of the novel circuit delay methods proposed in this paper was actually measured by a high sampling rate oscilloscope actual measurement. The measurement result shows that the accuracy of the distance simulated by the circuit delay is increased from +/- 0.75m up to +/- 0.15m. The accuracy of the simulated distance is greatly improved in simulated test for high precision pulsed range finder.

  2. Development and preliminary validation of the focused analgesia selection test to identify accurate pain reporters

    PubMed Central

    Treister, Roi; Eaton, Thomas A; Trudeau, Jeremiah J; Elder, Harrison; Katz, Nathaniel P

    2017-01-01

    Clinical trials of analgesics have been plagued with poor assay sensitivity due, in part, to variability in subjects’ pain reporting. Herein, we develop and evaluate the focused analgesia selection test (FAST), a method to measure patients’ pain reporting skills. Subjects with osteoarthritis of the hip, knee, and/or ankle with pain intensity of ≥3/10 on a 0–10 numerical rating scale were enrolled. Subjects underwent the FAST procedure, which consists of recording subjects’ pain reports in response to repeated administration of thermal noxious stimuli of various intensities applied on the arm with the Medoc® Thermal Sensory Analyzer II. Subjects also rated non-noxious stimuli consisting of visual contrast rating. After performing an exercise task, subjects also rated clinical pain and were asked to report whether their pain had increased, decreased, or stayed the same. Overall, 88 subjects were enrolled, and 83 were included in the analyses. FAST’s outcomes including the R2, intraclass correlation coefficient (ICC), and coefficient of variation (CoV) indicated that subjects’ pain reporting skills were widely distributed. Higher FAST ICC significantly predicted greater changes in clinical pain following exercise (p=0.017), whereas the visual contrast test did not predict postexercise pain. FAST is the first method that measures subjects’ pain reporting skills. Using FAST to enrich clinical trials with “good” pain reporters (with high FAST ICC) could increase assay sensitivity. Further evaluation of FAST is ongoing. PMID:28243138

  3. Bacterial Cytological Profiling (BCP) as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus

    PubMed Central

    Quach, D.T.; Sakoulas, G.; Nizet, V.; Pogliano, J.; Pogliano, K.

    2016-01-01

    Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP), which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA) and -resistant (MRSA) clinical isolates of S. aureus (n = 71) within 1–2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS) from daptomycin non-susceptible (DNS) S. aureus strains (n = 20) within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice. PMID:26981574

  4. Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults.

    PubMed

    Östberg, Per; Backlund, Charlotte; Lindström, Emma

    2016-10-01

    Few comprehensive spelling tests are available in Swedish, and none have been validated in adults with reading and writing disorders. The recently developed STAVUX test includes word and pseudoword spelling subtests with high internal consistency and adult norms stratified by education. This study evaluated the convergent and diagnostic validity of STAVUX in adults with dyslexia. Forty-six adults, 23 with dyslexia and 23 controls, took STAVUX together with a standard word-decoding test and a self-rated measure of spelling skills. STAVUX subtest scores showed moderate to strong correlations with word-decoding scores and predicted self-rated spelling skills. Word and pseudoword subtest scores both predicted dyslexia status. Receiver-operating characteristic (ROC) analysis showed excellent diagnostic discriminability. Sensitivity was 91% and specificity 96%. In conclusion, the results of this study support the convergent and diagnostic validity of STAVUX.

  5. Mathematics diagnostic testing in engineering: an international comparison between Ireland and Portugal

    NASA Astrophysics Data System (ADS)

    Carr, M.; Fidalgo, C.; Bigotte de Almeida, M. E.; Branco, J. R.; Santos, V.; Murphy, E.; Fhloinn, E. Ní

    2015-09-01

    Concern has been expressed throughout Europe about the significant deficiencies in the basic mathematical skills of many engineering undergraduates. Mathematics diagnostic tests in the UK, Ireland and Portugal have shown these shortcomings, which provide a challenge to those striving to introduce more innovative educational practices into engineering education, such as projects or real-world problems. Every year, in the Dublin Institute of Technology (Ireland) and the Instituto Superior de Engenharia de Coimbra (Portugal), a diagnostic test is given to incoming first-year students. A comparison showed some potentially interesting differences between these students. In September 2013, a project was undertaken to compare mathematical competencies of incoming engineering students in both countries. A modified diagnostic test was devised and the results were then compared to ascertain if there are common areas of difficulty between students in Ireland and Portugal, or evidence of one group significantly outperforming the other in a particular area.

  6. The development of rapid and accurate screening test for RET hotspot somatic and germline mutations in MEN2 syndromes.

    PubMed

    Zupan, Andrej; Glavač, Damjan

    2015-12-01

    Medullary thyroid carcinoma (MTC) is a rare endocrine malignancy with distinctive features separating it from other thyroid cancers. Cancer may be sporadic or occur as a consequence of the hereditary syndrome called multiple endocrine neoplasia type 2 (MEN2) with three distinct phenotypes in MEN2A, MEN2B and FMTC. Each variant of MEN2 results from different RET gene mutations, with a good genotype-phenotype correlation. The goal of the study was to develop a fast and accurate screening method for a reliable detection of hot-spot RET germline and sporadic tumor mutations. From a cohort of 191 patients with MTC and their relatives, 38 tested positive and 31 tested negative for a germline or somatic tumor RET mutation were selected. A positive HRM mutation pattern was detected in all mutation-positive patients and altogether the method was able to clearly differentiate between twenty different genotypes. A novel germline variant p.Ala639Thr was detected in MTC patient, which was determined to be likely benign. Analytical specificity was determined to be 98.6% and a sensitivity threshold was determined to be 30%. The fast and accurate HRM method reduces the turnaround time providing fast and important information, especially when targeted anti-tyrosine kinase therapy on tumor samples is considered. Overall, we developed a high-throughput, accurate and cost-effective approach for the detection of RET germline and sporadic tumor mutations.

  7. Diagnostic development and support of MHD Test Facilities. Technical progress report, October 1991--December 1991

    SciTech Connect

    Not Available

    1994-07-01

    The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for magnetohydrodynamic (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery (HRSR) support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL`s computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

  8. Diagnostic development and support of MHD test facilities. Technical progress report, January--March 1991

    SciTech Connect

    Shepard, W.S.; Cook, R.L.

    1991-12-31

    The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for magnetohydrodynamic (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery (HRSR) support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL`S computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

  9. The role of neurologists and diagnostic tests in the management of distal symmetric polyneuropathy

    PubMed Central

    Callaghan, Brian C.; Kerber, Kevin A.; Lisabeth, Lynda L.; Morgenstern, Lewis B.; Longoria, Ruth; Rodgers, Ann; Longwell, Paxton; Feldman, Eva L.

    2014-01-01

    Importance Distal symmetric polyneuropathy (DSP) is a prevalent condition resulting in high costs from diagnostic testing. However, the role of neurologists and diagnostic tests on patient care is unknown. Objective To determine how often neurologists and diagnostic tests influence the diagnosis and management of DSP patients in a community setting. Design We utilized a validated case-capture method (ICD-9 screening technique with subsequent medical chart abstraction) to identify patients with a new DSP diagnosis (retrospective cohort). Using a structured data abstraction process, diagnostic testing, diagnoses rendered (before and after testing), and subsequent management were recorded. Setting Community neurologist’s outpatient offices in Corpus Christi, Texas. Participants Patients meeting the Toronto consensus criteria for probable DSP. Main Outcome Measure Changes in etiology and management after diagnostic testing by neurologists. Results Between 1/1/2010–3/31/2011, we identified 458 DSP patients followed for mean (SD) 435.3 (44.1) days. Neurologists identified a cause of DSP in 63.5% of cases prior to their diagnostic testing. Seventy-one patients (15.5%) had a new DSP cause discovered after testing by neurologists. The most common new diagnoses were pre-diabetes (N=28), B12 deficiency (N=20), diabetes (N=8), and thyroid disease (N=8). Management changes were common (63.1%), usually related to neuropathic pain management (77.5%). Disease modifying management changes occurred in 24.7% with diabetes management (N=45), starting vitamins (N=39), advising diet/exercise (N=33), and adjusting thyroid medications (N=10) the most common. Electrodiagnostic testing and MRIs of the neuroaxis rarely led to management changes. Conclusions and Relevance Neurologists diagnosed the cause of DSP in almost two-thirds of patients prior to their diagnostic testing. Inexpensive blood tests for diabetes, thyroid dysfunction, and B12 deficiency, allowed neurologists to identify

  10. Understanding laboratory testing in diagnostic uncertainty: a qualitative study in general practice.

    PubMed Central

    van der Weijden, Trudy; van Bokhoven, Marloes A; Dinant, Geert-Jan; van Hasselt, Cathelijne M; Grol, Richard P T M

    2002-01-01

    BACKGROUND: Better knowledge of the professional's motives for ordering laboratory tests in the case of diagnostic uncertainty may lead to interventions directed at reducing unnecessary testing. AIM: To gain insight into the general practitioner's (GP's) motives for ordering laboratory tests for patients presenting with unexplained complaints. DESIGN OF STUDY: Semi-structured interviews based on surgery observations. SETTING: Twenty-one general practices in rural and urban areas of The Netherlands. METHOD: Investigation of the GP's perception of determinants of test-ordering behaviour in the situation of diagnostic uncertainty. The interviews were structured by evaluating the consultations and test-ordering performance of that day. RESULTS: Dutch GPs vary considerably in their motives for ordering tests. Numerous motives emerged from the data. Some examples of important themes include: personal routines; tolerance of diagnostic uncertainty; time pressure; and tactical motives for test ordering. Complying with the perceived needs of the patient for reassurance through testing is seen as an easy, cost- and time-effective strategy. A clear hierarchy in the determinants was not found. CONCLUSION: The decision to request laboratory testing is the result of a complex interaction of considerations that are often conflicting. Designers of interventions meant to improve the ordering of tests should be aware of the numerous determinants, and take contextual variables into account. PMID:12528582

  11. Protostellar hydrodynamics: Constructing and testing a spacially and temporally second-order accurate method. 2: Cartesian coordinates

    NASA Technical Reports Server (NTRS)

    Myhill, Elizabeth A.; Boss, Alan P.

    1993-01-01

    In Boss & Myhill (1992) we described the derivation and testing of a spherical coordinate-based scheme for solving the hydrodynamic equations governing the gravitational collapse of nonisothermal, nonmagnetic, inviscid, radiative, three-dimensional protostellar clouds. Here we discuss a Cartesian coordinate-based scheme based on the same set of hydrodynamic equations. As with the spherical coorrdinate-based code, the Cartesian coordinate-based scheme employs explicit Eulerian methods which are both spatially and temporally second-order accurate. We begin by describing the hydrodynamic equations in Cartesian coordinates and the numerical methods used in this particular code. Following Finn & Hawley (1989), we pay special attention to the proper implementations of high-order accuracy, finite difference methods. We evaluate the ability of the Cartesian scheme to handle shock propagation problems, and through convergence testing, we show that the code is indeed second-order accurate. To compare the Cartesian scheme discussed here with the spherical coordinate-based scheme discussed in Boss & Myhill (1992), the two codes are used to calculate the standard isothermal collapse test case described by Bodenheimer & Boss (1981). We find that with the improved codes, the intermediate bar-configuration found previously disappears, and the cloud fragments directly into a binary protostellar system. Finally, we present the results from both codes of a new test for nonisothermal protostellar collapse.

  12. Vaccination-associated anaphylaxis in adults: diagnostic testing ruling out IgE-mediated vaccine allergy.

    PubMed

    Seitz, Cornelia S; Bröcker, Eva-B; Trautmann, Axel

    2009-06-12

    Re-vaccinations in patients with a history of anaphylaxis after vaccine injection have to be avoided because of the potential risk of recurrent anaphylaxis. However, without diagnostic work-up vaccine allergy remains a presumption and necessary vaccinations may be unjustified withheld. In the last 7 years all patients referred to our allergy clinic with a diagnosis of vaccination-induced anaphylaxis were subjected to allergologic diagnostic procedures to identify IgE-mediated allergy. We evaluated 38 patients with a history of vaccination-associated anaphylaxis. The diagnostic procedure included skin testing and challenge tests, i.e. re-vaccination with the suspected vaccine. In all 38 patients negative skin tests and tolerated challenge tests ruled out IgE-mediated allergic anaphylaxis to vaccine components. Diagnostic testing after suspected vaccination-induced anaphylaxis should be performed to rule out IgE-mediated allergy to the incriminated vaccine and its constituents and to enable future vaccinations with the tested compounds. Therefore, a history of anaphylaxis after vaccination may not be an absolute contraindication for re-vaccination.

  13. Perspectives on Introduction and Implementation of New Point-of-Care Diagnostic Tests

    PubMed Central

    Palamountain, Kara M.; Baker, Jeff; Cowan, Elliot P.; Essajee, Shaffiq; Mazzola, Laura T.; Metzler, Mutsumi; Schito, Marco; Stevens, Wendy S.; Young, Gloria J.

    2012-01-01

    In recent years, there has been significant investment from both the private and public sectors in the development of diagnostic technologies to meet the need for human immunodeficiency virus (HIV) and tuberculosis testing in low-resource settings. Future investments should ensure that the most appropriate technologies are adopted in settings where they will have a sustainable impact. Achieving these aims requires the involvement of many stakeholders, as their needs, operational constraints, and priorities are often distinct. Here, we discuss these considerations from different perspectives representing those of various stakeholders involved in the development, introduction, and implementation of diagnostic tests. We also discuss some opportunities to address these considerations. PMID:22402038

  14. How Accurate Is the Prediction of Maximal Oxygen Uptake with Treadmill Testing?

    PubMed Central

    Wicks, John R.; Oldridge, Neil B.

    2016-01-01

    Background Cardiorespiratory fitness measured by treadmill testing has prognostic significance in determining mortality with cardiovascular and other chronic disease states. The accuracy of a recently developed method for estimating maximal oxygen uptake (VO2peak), the heart rate index (HRI), is dependent only on heart rate (HR) and was tested against oxygen uptake (VO2), either measured or predicted from conventional treadmill parameters (speed, incline, protocol time). Methods The HRI equation, METs = 6 x HRI– 5, where HRI = maximal HR/resting HR, provides a surrogate measure of VO2peak. Forty large scale treadmill studies were identified through a systematic search using MEDLINE, Google Scholar and Web of Science in which VO2peak was either measured (TM-VO2meas; n = 20) or predicted (TM-VO2pred; n = 20) based on treadmill parameters. All studies were required to have reported group mean data of both resting and maximal HRs for determination of HR index-derived oxygen uptake (HRI-VO2). Results The 20 studies with measured VO2 (TM-VO2meas), involved 11,477 participants (median 337) with a total of 105,044 participants (median 3,736) in the 20 studies with predicted VO2 (TM-VO2pred). A difference of only 0.4% was seen between mean (±SD) VO2peak for TM- VO2meas and HRI-VO2 (6.51±2.25 METs and 6.54±2.28, respectively; p = 0.84). In contrast, there was a highly significant 21.1% difference between mean (±SD) TM-VO2pred and HRI-VO2 (8.12±1.85 METs and 6.71±1.92, respectively; p<0.001). Conclusion Although mean TM-VO2meas and HRI-VO2 were almost identical, mean TM-VO2pred was more than 20% greater than mean HRI-VO2. PMID:27875547

  15. Assessing value of innovative molecular diagnostic tests in the concept of predictive, preventive, and personalized medicine.

    PubMed

    Akhmetov, Ildar; Bubnov, Rostyslav V

    2015-01-01

    Molecular diagnostic tests drive the scientific and technological uplift in the field of predictive, preventive, and personalized medicine offering invaluable clinical and socioeconomic benefits to the key stakeholders. Although the results of diagnostic tests are immensely influential, molecular diagnostic tests (MDx) are still grudgingly reimbursed by payers and amount for less than 5 % of the overall healthcare costs. This paper aims at defining the value of molecular diagnostic test and outlining the most important components of "value" from miscellaneous assessment frameworks, which go beyond accuracy and feasibility and impact the clinical adoption, informing healthcare resource allocation decisions. The authors suggest that the industry should facilitate discussions with various stakeholders throughout the entire assessment process in order to arrive at a consensus about the depth of evidence required for positive marketing authorization or reimbursement decisions. In light of the evolving "value-based healthcare" delivery practices, it is also recommended to account for social and ethical parameters of value, since these are anticipated to become as critical for reimbursement decisions and test acceptance as economic and clinical criteria.

  16. Bovine paratuberculosis: a review of the advantages and disadvantages of different diagnostic tests.

    PubMed

    Gilardoni, Liliana R; Paolicchi, Fernando A; Mundo, Silvia L

    2012-01-01

    Paratuberculosis (PTB), or Johne's disease, is a chronic infectious granulomatous enteritis of ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). It is characterized by diarrhea and progressive cachexia, which may cause the death of the animal. Calves are the most susceptible to infection. Infected animals excrete Map mainly by the feces. PTB is endemic worldwide, with high prevalence levels, strong economic impact and public health relevance because of its possible association with Crohn's disease. Although the current reference diagnostic test is identification of Map in the bacterial culture, there are different diagnostic tests to identify infected individuals and/or herds. The sensitivity and specificity of these tests vary according to the stage of the disease in the animals to be evaluated. The correct choice and application of each of these diagnostic tests will ensure their success and may allow to establish a control program. The aim of this work is to review and discuss the different diagnostic tests used in the detection of Map-infected animals, focusing on their advantages and disadvantages.

  17. Rapid Diagnostic Tests for Malaria Diagnosis in the Peruvian Amazon: Impact of pfhrp2 Gene Deletions and Cross-Reactions

    PubMed Central

    Maltha, Jessica; Gamboa, Dionicia; Bendezu, Jorge; Sanchez, Luis; Cnops, Lieselotte; Gillet, Philippe; Jacobs, Jan

    2012-01-01

    Background In the Peruvian Amazon, Plasmodium falciparum and Plasmodium vivax malaria are endemic in rural areas, where microscopy is not available. Malaria rapid diagnostic tests (RDTs) provide quick and accurate diagnosis. However, pfhrp2 gene deletions may limit the use of histidine-rich protein-2 (PfHRP2) detecting RDTs. Further, cross-reactions of P. falciparum with P. vivax-specific test lines and vice versa may impair diagnostic specificity. Methods Thirteen RDT products were evaluated on 179 prospectively collected malaria positive samples. Species diagnosis was performed by microscopy and confirmed by PCR. Pfhrp2 gene deletions were assessed by PCR. Results Sensitivity for P. falciparum diagnosis was lower for PfHRP2 compared to P. falciparum-specific Plasmodium lactate dehydrogenase (Pf-pLDH)- detecting RDTs (71.6% vs. 98.7%, p<0.001). Most (19/21) false negative PfHRP2 results were associated with pfhrp2 gene deletions (25.7% of 74 P. falciparum samples). Diagnostic sensitivity for P. vivax (101 samples) was excellent, except for two products. In 10/12 P. vivax-detecting RDT products, cross-reactions with the PfHRP2 or Pf-pLDH line occurred at a median frequency of 2.5% (range 0%–10.9%) of P. vivax samples assessed. In two RDT products, two and one P. falciparum samples respectively cross-reacted with the Pv-pLDH line. Two Pf-pLDH/pan-pLDH-detecting RDTs showed excellent sensitivity with few (1.0%) cross-reactions but showed faint Pf-pLDH lines in 24.7% and 38.9% of P. falciparum samples. Conclusion PfHRP2-detecting RDTs are not suitable in the Peruvian Amazon due to pfhrp2 gene deletions. Two Pf-pLDH-detecting RDTs performed excellently and are promising RDTs for this region although faint test lines are of concern. PMID:22952633

  18. Rocket engine exhaust plume diagnostics and health monitoring/management during ground testing

    NASA Technical Reports Server (NTRS)

    Chenevert, D. J.; Meeks, G. R.; Woods, E. G.; Huseonica, H. F.

    1992-01-01

    The current status of a rocket exhaust plume diagnostics program sponsored by NASA is reviewed. The near-term objective of the program is to enhance test operation efficiency and to provide for safe cutoff of rocket engines prior to incipient failure, thereby avoiding the destruction of the engine and the test complex and preventing delays in the national space program. NASA programs that will benefit from the nonintrusive remote sensed rocket plume diagnostics and related vehicle health management and nonintrusive measurement program are Space Shuttle Main Engine, National Launch System, National Aero-Space Plane, Space Exploration Initiative, Advanced Solid Rocket Motor, and Space Station Freedom. The role of emission spectrometry and other types of remote sensing in rocket plume diagnostics is discussed.

  19. [Laboratory practices: diagnostics and antibiotics resistance testing of Neisseria gonorrhoeae in Germany].

    PubMed

    Loenenbach, Anna; Dudareva-Vizule, S; Buder, S; Sailer, A; Kohl, P K; Bremer, V

    2015-08-01

    Recent years have seen a world-wide increase in antimicrobial resistance (AMR) in cases of infection with Neisseria gonorrhoeae (NG). NG infection is not notifiable in Germany and there is a lack of information available about the spread and AMR of NG infections. The objective of the study was to provide information on diagnostic methods and AMR testing in cases of NG infections in German laboratories. A cross-sectional survey was undertaken in Germany between June and August 2013 using an online questionnaire. Laboratories performing NG diagnostics were identified and described with regard to the diagnostic methods used, the number of tests performed, the antibiotics tested and the AMR observed, in addition to general laboratory information. In total, 188 of the 521 participating laboratories performed NG diagnostics; these were included in the further statistical analysis. 92.6 % of the 188 laboratories performed culture. A median of 60 (IQR 15-270) samples per quarter (SPQ) were tested, with an overall positivity rate of 4.1 and 6.9 % among men. Most (82.1 %) of the 151 laboratories performing NG culture tested for AMR as well. The most frequently tested antibiotics were ciprofloxacin (94.8 %), penicillin (93.1 %), doxycycline (70.0 %) and ceftriaxone (67.2 %). The most frequently observed AMR ever were those against ciprofloxacin (87.1 %), penicillin (78.3 %), doxycycline (56.6 %) and azithromycin (35.1 %; all percentages refer to laboratories). The laboratories used different standards regarding susceptibility criteria. The emergence and spread of AMR shows that it is crucial to assess and monitor the scope and trends of multidrug-resistant gonorrhea. The data collected on diagnostic methods and AMR testing in cases of NG infections in German laboratories constitute an important basis for future monitoring.

  20. Stretch calculated from grip distance accurately approximates mid-specimen stretch in large elastic arteries in uniaxial tensile tests

    PubMed Central

    Tian, Lian; Henningsen, Joseph; Salick, Max R.; Crone, Wendy C.; Gunderson, McLean; Dailey, Seth H.; Chesler, Naomi C.

    2015-01-01

    The mechanical properties of vascular tissues affect hemodynamics and can alter disease progression. The uniaxial tensile test is a simple and effective method for determining the stress-strain relationship in arterial tissue ex vivo. To enable calculation of strain, stretch can be measured directly with image tracking of markers on the tissue or indirectly from the distance between the grips used to hold the specimen. While the imaging technique is generally considered more accurate, it also requires more analysis, and the grip distance method is more widely used. The purpose of this study is to compare the stretch of the testing specimen calculated from the grip distance method to that obtained from the imaging method for canine descending aortas and large proximal pulmonary arteries. Our results showed a significant difference in stretch between the two methods; however, this difference was consistently less than 2%. Therefore, the grip distance method is an accurate approximation of the stretch in large elastic arteries in the uniaxial tensile test. PMID:25881308

  1. Hydrogen sulfide detection based on reflection: from a poison test approach of ancient China to single-cell accurate localization.

    PubMed

    Kong, Hao; Ma, Zhuoran; Wang, Song; Gong, Xiaoyun; Zhang, Sichun; Zhang, Xinrong

    2014-08-05

    With the inspiration of an ancient Chinese poison test approach, we report a rapid hydrogen sulfide detection strategy in specific areas of live cells using silver needles with good spatial resolution of 2 × 2 μm(2). Besides the accurate-localization ability, this reflection-based strategy also has attractive merits of convenience and robust response when free pretreatment and short detection time are concerned. The success of endogenous H2S level evaluation in cellular cytoplasm and nuclear of human A549 cells promises the application potential of our strategy in scientific research and medical diagnosis.

  2. Evaluation of three rapid diagnostic tests for the detection of human infections with Plasmodium knowlesi

    PubMed Central

    2014-01-01

    Background Plasmodium knowlesi, a malaria parasite of Southeast Asian macaques, infects humans and can cause fatal malaria. It is difficult to diagnose by microscopy because of morphological similarity to Plasmodium malariae. Nested PCR assay is the most accurate method to distinguish P. knowlesi from other Plasmodium species but is not cost effective in resource-poor settings. Rapid diagnostic tests (RDTs) are recommended for settings where malaria is prevalent. In this study, the effectiveness of three RDTs in detecting P. knowlesi from fresh and frozen patient blood samples was evaluated. Methods Forty malaria patients (28 P. knowlesi, ten P. vivax and two P. falciparum) diagnosed by microscopy were recruited in Sarawak, Malaysian Borneo during a 16-month period. Patient blood samples were used to determine parasitaemia by microscopy, confirm the Plasmodium species present by PCR and evaluate three RDTs: OptiMAL-IT, BinaxNOW® Malaria and Paramax-3. The RDTs were also evaluated using frozen blood samples from 41 knowlesi malaria patients. Results OptiMAL-IT was the most sensitive RDT, with a sensitivity of 71% (20/28; 95% CI = 54-88%) for fresh and 73% (30/41; 95% CI = 59-87%) for frozen knowlesi samples. However, it yielded predominantly falciparum-positive results due to cross-reactivity of the P. falciparum test reagent with P. knowlesi. BinaxNOW® Malaria correctly detected non-P. falciparum malaria in P. knowlesi samples but was the least sensitive, detecting only 29% (8/28; 95% CI = 12-46%) of fresh and 24% (10/41; 95% CI = 11-37%) of frozen samples. The Paramax-3 RDT tested positive for P. vivax with PCR-confirmed P. knowlesi samples with sensitivities of 40% (10/25; 95% CI = 21-59%) with fresh and 32% (13/41; 95% CI = 17-46%) with frozen samples. All RDTs correctly identified P. falciparum- and P. vivax-positive controls with parasitaemias above 2,000 parasites/μl blood. Conclusions The RDTs detected Plasmodium in P. knowlesi-infected blood samples with

  3. Development and preparation of lead-containing paint films and diagnostic test materials.

    PubMed

    Binstock, David; Gutknecht, William; Sorrell, Kristen; Haas, Curtis; Winstead, Wayne; McCombs, Michelle; Brown, Gordon; Salmons, Cynthia; Harper, Sharon L

    2012-05-01

    Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.

  4. Utility of composite reference standards and latent class analysis in evaluating the clinical accuracy of diagnostic tests for pertussis.

    PubMed

    Baughman, Andrew L; Bisgard, Kristine M; Cortese, Margaret M; Thompson, William W; Sanden, Gary N; Strebel, Peter M

    2008-01-01

    Numerous evaluations of the clinical sensitivity and specificity of PCR and serologic assays for Bordetella pertussis have been hampered by the low sensitivity of culture, the gold standard test, which leads to biased accuracy estimates. The bias can be reduced by using statistical approaches such as the composite reference standard (CRS) (e.g., positive if culture or serology positive; negative otherwise) or latent class analysis (LCA), an internal reference standard based on a statistical model. We illustrated the benefits of the CRS and LCA approaches by reanalyzing data from a 1995 to 1996 study of cough illness among 212 patients. The accuracy of PCR in this study was evaluated using three reference standards: culture, CRS, and LCA. Using specimens obtained 0 to 34 days after cough onset, estimates of the sensitivity of PCR obtained using CRS (47%) and LCA (34%) were lower than the culture-based estimate (62%). The CRS and LCA approaches, which utilized more than one diagnostic marker of pertussis, likely produced more accurate reference standards than culture alone. In general, the CRS approach is simple, with a well-defined disease status. LCA requires statistical modeling but incorporates more indicators of disease than CRS. When three or more indicators of pertussis are available, these approaches should be used in evaluations of pertussis diagnostic tests.

  5. Assessing the impact of next-generation rapid diagnostic tests on Plasmodium falciparum malaria elimination strategies.

    PubMed

    Slater, Hannah C; Ross, Amanda; Ouédraogo, André Lin; White, Lisa J; Nguon, Chea; Walker, Patrick G T; Ngor, Pengby; Aguas, Ricardo; Silal, Sheetal P; Dondorp, Arjen M; La Barre, Paul; Burton, Robert; Sauerwein, Robert W; Drakeley, Chris; Smith, Thomas A; Bousema, Teun; Ghani, Azra C

    2015-12-03

    Mass-screen-and-treat and targeted mass-drug-administration strategies are being considered as a means to interrupt transmission of Plasmodium falciparum malaria. However, the effectiveness of such strategies will depend on the extent to which current and future diagnostics are able to detect those individuals who are infectious to mosquitoes. We estimate the relationship between parasite density and onward infectivity using sensitive quantitative parasite diagnostics and mosquito feeding assays from Burkina Faso. We find that a diagnostic with a lower detection limit of 200 parasites per microlitre would detect 55% of the infectious reservoir (the combined infectivity to mosquitoes of the whole population weighted by how often each individual is bitten) whereas a test with a limit of 20 parasites per microlitre would detect 83% and 2 parasites per microlitre would detect 95% of the infectious reservoir. Using mathematical models, we show that increasing the diagnostic sensitivity from 200 parasites per microlitre (equivalent to microscopy or current rapid diagnostic tests) to 2 parasites per microlitre would increase the number of regions where transmission could be interrupted with a mass-screen-and-treat programme from an entomological inoculation rate below 1 to one of up to 4. The higher sensitivity diagnostic could reduce the number of treatment rounds required to interrupt transmission in areas of lower prevalence. We predict that mass-screen-and-treat with a highly sensitive diagnostic is less effective than mass drug administration owing to the prophylactic protection provided to uninfected individuals by the latter approach. In low-transmission settings such as those in Southeast Asia, we find that a diagnostic tool with a sensitivity of 20 parasites per microlitre may be sufficient for targeted mass drug administration because this diagnostic is predicted to identify a similar village population prevalence compared with that currently detected using

  6. A Technology for Developing Instructional Materials. Vol. 3, Handbook. Part F, Develop Diagnostic and Evaluative Tests.

    ERIC Educational Resources Information Center

    Gropper, George L.

    This document, sixth in a series of 11 subvolumes of a handbook prepared to provide training for educational research and development personnel in the development of instructional materials, deals with the task of developing diagnostic and evaluative tests. The document is organized according to the four sequential steps involved in performing the…

  7. Mathematics Diagnostic Testing in Engineering: An International Comparison between Ireland and Portugal

    ERIC Educational Resources Information Center

    Carr, M.; Fidalgo, C.; Bigotte de Almeida, M. E.; Branco, J. R.; Santos, V.; Murphy, E.; Ní Fhloinn, E.

    2015-01-01

    Concern has been expressed throughout Europe about the significant deficiencies in the basic mathematical skills of many engineering undergraduates. Mathematics diagnostic tests in the UK, Ireland and Portugal have shown these shortcomings, which provide a challenge to those striving to introduce more innovative educational practices into…

  8. A Needs-Based Approach to the Development of a Diagnostic College English Speaking Test

    ERIC Educational Resources Information Center

    Zhao, Zhongbao

    2014-01-01

    This paper investigated the current situation of oral English teaching, learning, and assessment at the tertiary level in China through needs analysis and explored the implications for the development of a diagnostic speaking test. Through random sampling, the researcher administered both a student questionnaire and a teacher questionnaire to over…

  9. 75 FR 15443 - Advancing the Development of Diagnostic Tests and Biomarkers for Tuberculosis; Public Workshop...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-29

    ...-resistant TB (MDR TB) and extensively drug-resistant TB (XDR TB). Both plans addressed domestic and global strategies, including partnerships with global agencies, as well as detailed action steps and specific agency... strategies that would expedite the development of new diagnostic tests and biomarkers for TB. Date and...

  10. Comparison of the Minnesota Percepto-Diagnostic Test and Bender-Gestalt: Relationship with Achievement Criteria.

    ERIC Educational Resources Information Center

    Fuller, Gerald B.; Wallbrown, Fred H.

    1983-01-01

    Compared the Bender Gestalt (BD) and Minnesota Percepto-Diagnostic Test (MPD) in predicting academic achievement for younger children (N=69). Results suggested that the MPD is more sensitive than the Bender in identifying visual-motor perception areas of achievement performance problems. (LLL)

  11. The Effects of Diagnostic Testing and Remediation on Science Achievement and Retention.

    ERIC Educational Resources Information Center

    Long, Joe C.; And Others

    The purpose of this study was to provide students with differing types of learning needs instruction following diagnostic testing; also examined were the effects of the instruction on science achievement and retention. A total of 154 seventh-grade students from six classes completed a five-week block of instruction in earth science composed of…

  12. Web-Based Two-Tier Diagnostic Test and Remedial Learning Experiment

    ERIC Educational Resources Information Center

    Lai, Ah-Fur; Chen, Deng-Jyi

    2010-01-01

    Offering a series of diagnosis and individual remedial learning activities for a general class by means of web and multimedia technology can overcome the dilemma of conventional diagnosis and remedial instruction. The study proposes a three-layer conceptual framework and adopts a two-tier diagnostic test theory to develop a web-based two-tier…

  13. Diagnostic test for prenatal identification of Down's syndrome and mental retardation and gene therapy therefor

    DOEpatents

    Smith, Desmond J.; Rubin, Edward M.

    2000-01-01

    A a diagnostic test useful for prenatal identification of Down syndrome and mental retardation. A method for gene therapy for correction and treatment of Down syndrome. DYRK gene involved in the ability to learn. A method for diagnosing Down's syndrome and mental retardation and an assay therefor. A pharmaceutical composition for treatment of Down's syndrome mental retardation.

  14. Development and Preparation of Lead-Containing Paint Films and Diagnostic Test Materials

    EPA Science Inventory

    Lead in paint continues to be a threat to children’s health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnost...

  15. Restrictive Stochastic Item Selection Methods in Cognitive Diagnostic Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Chun; Chang, Hua-Hua; Huebner, Alan

    2011-01-01

    This paper proposes two new item selection methods for cognitive diagnostic computerized adaptive testing: the restrictive progressive method and the restrictive threshold method. They are built upon the posterior weighted Kullback-Leibler (KL) information index but include additional stochastic components either in the item selection index or in…

  16. Diagnostic Classification Models and Multidimensional Adaptive Testing: A Commentary on Rupp and Templin

    ERIC Educational Resources Information Center

    Frey, Andreas; Carstensen, Claus H.

    2009-01-01

    On a general level, the objective of diagnostic classifications models (DCMs) lies in a classification of individuals regarding multiple latent skills. In this article, the authors show that this objective can be achieved by multidimensional adaptive testing (MAT) as well. The authors discuss whether or not the restricted applicability of DCMs can…

  17. Application of a Cognitive Diagnostic Model to a High-Stakes Reading Comprehension Test

    ERIC Educational Resources Information Center

    Ravand, Hamdollah

    2016-01-01

    General cognitive diagnostic models (CDM) such as the generalized deterministic input, noisy, "and" gate (G-DINA) model are flexible in that they allow for both compensatory and noncompensatory relationships among the subskills within the same test. Most of the previous CDM applications in the literature have been add-ons to simulation…

  18. Test Review: Brown Attention-Deficit Disorder Scales and Brown ADD Diagnostic Forms.

    ERIC Educational Resources Information Center

    Muniz, Linda

    1996-01-01

    This article on the Brown Attention-Deficit Disorder (ADD) Scale for Adolescents and the Brown ADD Scale for Adults describes the tests' recommended uses, administration, components, standardization, reliability, and validity. The self-report measures are designed for initial screening, as one part of a comprehensive diagnostic assessment, and for…

  19. The Changing Landscape of Molecular Diagnostic Testing: Implications for Academic Medical Centers

    PubMed Central

    Rehm, Heidi L.; Hynes, Elizabeth; Funke, Birgit H.

    2016-01-01

    Over the last decade, the field of molecular diagnostics has undergone tremendous transformation, catalyzed by the clinical implementation of next generation sequencing (NGS). As technical capabilities are enhanced and current limitations are addressed, NGS is increasingly capable of detecting most variant types and will therefore continue to consolidate and simplify diagnostic testing. It is likely that genome sequencing will eventually serve as a universal first line test for disorders with a suspected genetic origin. Academic Medical Centers (AMCs), which have been at the forefront of this paradigm shift are now presented with challenges to keep up with increasing technical, bioinformatic and interpretive complexity of NGS-based tests in a highly competitive market. Additional complexity may arise from altered regulatory oversight, also triggered by the unprecedented scope of NGS-based testing, which requires new approaches. However, these challenges are balanced by unique opportunities, particularly at the interface between clinical and research operations, where AMCs can capitalize on access to cutting edge research environments and establish collaborations to facilitate rapid diagnostic innovation. This article reviews present and future challenges and opportunities for AMC associated molecular diagnostic laboratories from the perspective of the Partners HealthCare Laboratory for Molecular Medicine (LMM). PMID:26828522

  20. 30 CFR 250.525 - What do I submit if my casing diagnostic test requires action?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What do I submit if my casing diagnostic test requires action? 250.525 Section 250.525 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION... CONTINENTAL SHELF Oil and Gas Well-Completion Operations Casing Pressure Management § 250.525 What do I...

  1. 30 CFR 250.520 - When do I have to perform a casing diagnostic test?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to perform a casing diagnostic test? 250.520 Section 250.520 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas...

  2. 30 CFR 250.525 - What do I submit if my casing diagnostic test requires action?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What do I submit if my casing diagnostic test requires action? 250.525 Section 250.525 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas...

  3. 30 CFR 250.522 - When do I have to repeat casing diagnostic testing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to repeat casing diagnostic testing? 250.522 Section 250.522 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas...

  4. A Mixed Model Approach to Meta-Analysis of Diagnostic Studies with Binary Test Outcome

    ERIC Educational Resources Information Center

    Doebler, Philipp; Holling, Heinz; Bohning, Dankmar

    2012-01-01

    We propose 2 related models for the meta-analysis of diagnostic tests. Both models are based on the bivariate normal distribution for transformed sensitivities and false-positive rates. Instead of using the logit as a transformation for these proportions, we employ the "t"[subscript alpha] family of transformations that contains the log, logit,…

  5. An International Comparison Using a Diagnostic Testing Model: Turkish Students' Profile of Mathematical Skills on TIMSS-R

    ERIC Educational Resources Information Center

    Dogan, Enis; Tatsuoka, Kikumi

    2008-01-01

    This study illustrates how a diagnostic testing model can be used to make detailed comparisons between student populations participating in international assessments. The performance of Turkish students on the TIMSS-R mathematics test was reanalyzed with a diagnostic testing model called the Rule Space Model. First, mathematical and cognitive…

  6. Effects of a Web-Based Decision Aid Regarding Diagnostic Self-Testing. A Single-Blind Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Ickenroth, Martine H. P.; Grispen, J. E. J.; de Vries, N. K.; Dinant, G. J.; Ronda, G.; van der Weijden, T.

    2016-01-01

    Currently, there are many diagnostic self-tests on body materials available to consumers. The aim of this study was to assess the effect of an online decision aid on diagnostic self-testing for cholesterol and diabetes on knowledge among consumers with an intention to take these tests. A randomized controlled trial was designed. A total of 1259…

  7. Scratching Where They Itch: Evaluation of Feedback on a Diagnostic English Grammar Test for Taiwanese University Students

    ERIC Educational Resources Information Center

    Yin, Muchun; Sims, James; Cothran, Daniel

    2012-01-01

    Feedback to the test taker is a defining characteristic of diagnostic language testing (Alderson, 2005). This article reports on a study that investigated how much and in what ways students at a Taiwan university perceived the feedback to be useful on an online multiple-choice diagnostic English grammar test, both in general and by students of…

  8. Sensitive KIT D816V mutation analysis of blood as a diagnostic test in mastocytosis.

    PubMed

    Kristensen, Thomas; Vestergaard, Hanne; Bindslev-Jensen, Carsten; Møller, Michael Boe; Broesby-Olsen, Sigurd

    2014-05-01

    The recent progress in sensitive KIT D816V mutation analysis suggests that mutation analysis of peripheral blood (PB) represents a promising diagnostic test in mastocytosis. However, there is a need for systematic assessment of the analytical sensitivity and specificity of the approach in order to establish its value in clinical use. We therefore evaluated sensitive KIT D816V mutation analysis of PB as a diagnostic test in an entire case-series of adults with mastocytosis. We demonstrate for the first time that by using a sufficiently sensitive KIT D816V mutation analysis, it is possible to detect the mutation in PB in nearly all adult mastocytosis patients. The mutation was detected in PB in 78 of 83 systemic mastocytosis (94%) and 3 of 4 cutaneous mastocytosis patients (75%). The test was 100% specific as determined by analysis of clinically relevant control patients who all tested negative. Mutation analysis of PB was significantly more sensitive than serum tryptase >20 ng/mL. Of 27 patients with low tryptase, 26 tested mutation positive (96%). The test is furthermore readily available and we consider the results to serve as a foundation of experimental evidence to support the inclusion of the test in diagnostic algorithms and clinical practice in mastocytosis.

  9. Exact inference for the risk ratio with an imperfect diagnostic test.

    PubMed

    Reiczigel, J; Singer, J; Lang, Z S

    2017-01-01

    The risk ratio quantifies the risk of disease in a study population relative to a reference population. Standard methods of estimation and testing assume a perfect diagnostic test having sensitivity and specificity of 100%. However, this assumption typically does not hold, and this may invalidate naive estimation and testing for the risk ratio. We propose procedures that control for sensitivity and specificity of the diagnostic test, given the risks are measured by proportions, as it is in cross-sectional studies or studies with fixed follow-up times. These procedures provide an exact unconditional test and confidence interval for the true risk ratio. The methods also cover the case when sensitivity and specificity differ in the two groups (differential misclassification). The resulting test and confidence interval may be useful in epidemiological studies as well as in clinical and vaccine trials. We illustrate the method with real-life examples which demonstrate that ignoring sensitivity and specificity of the diagnostic test may lead to considerable bias in the estimated risk ratio.

  10. Are all significant P values created equal? The analogy between diagnostic tests and clinical research.

    PubMed

    Browner, W S; Newman, T B

    1987-05-08

    Just as diagnostic tests are most helpful in light of the clinical presentation, statistical tests are most useful in the context of scientific knowledge. Knowing the specificity and sensitivity of a diagnostic test is necessary, but insufficient: the clinician must also estimate the prior probability of the disease. In the same way, knowing the P value and power, or the confidence interval, for the results of a research study is necessary but insufficient: the reader must estimate the prior probability that the research hypothesis is true. Just as a positive diagnostic test does not mean that a patient has the disease, especially if the clinical picture suggests otherwise, a significant P value does not mean that a research hypothesis is correct, especially if it is inconsistent with current knowledge. Powerful studies are like sensitive tests in that they can be especially useful when the results are negative. Very low P values are like very specific tests; both result in few false-positive results due to chance. This Bayesian approach can clarify much of the confusion surrounding the use and interpretation of statistical tests.

  11. Excretion kinetics of 13C-urea breath test: influences of endogenous CO2 production and dose recovery on the diagnostic accuracy of Helicobacter pylori infection.

    PubMed

    Som, Suman; Maity, Abhijit; Banik, Gourab Dutta; Ghosh, Chiranjit; Chaudhuri, Sujit; Daschakraborty, Sunil Baran; Ghosh, Shibendu; Pradhan, Manik

    2014-09-01

    We report for the first time the excretion kinetics of the percentage dose of (13)C recovered/h ((13)C-PDR %/h) and cumulative PDR, i.e. c-PDR (%) to accomplish the highest diagnostic accuracy of the (13)C-urea breath test ((13)C-UBT) for the detection of Helicobacter pylori infection without any risk of diagnostic errors using an optical cavity-enhanced integrated cavity output spectroscopy (ICOS) method. An optimal diagnostic cut-off point for the presence of H. pylori infection was determined to be c-PDR (%) = 1.47 % at 60 min, using the receiver operating characteristic curve (ROC) analysis to overcome the "grey zone" containing false-positive and false-negative results of the (13)C-UBT. The present (13)C-UBT exhibited 100 % diagnostic sensitivity (true-positive rate) and 100 % specificity (true-negative rate) with an accuracy of 100 % compared with invasive endoscopy and biopsy tests. Our c-PDR (%) methodology also manifested both diagnostic positive and negative predictive values of 100 %, demonstrating excellent diagnostic accuracy. We also observed that the effect of endogenous CO2 production related to basal metabolic rates in individuals was statistically insignificant (p = 0.78) on the diagnostic accuracy. However, the presence of H. pylori infection was indicated by the profound effect of urea hydrolysis rate (UHR). Our findings suggest that the current c-PDR (%) is a valid and sufficiently robust novel approach for an accurate, specific, fast and noninvasive diagnosis of H. pylori infection, which could routinely be used for large-scale screening purposes and diagnostic assessment, i.e. for early detection and follow-up of patients.

  12. Operational modelling to guide implementation and scale-up of diagnostic tests within the health system: exploring opportunities for parasitic disease diagnostics based on example application for tuberculosis.

    PubMed

    Langley, Ivor; Adams, Emily; Doulla, Basra; Squire, S Bertel

    2014-12-01

    Research and innovation in the diagnosis of infectious and parasitic diseases has led to the development of several promising diagnostic tools, for example in malaria there is extensive literature concerning the use of rapid diagnostic tests. This means policymakers in many low and middle income countries need to make difficult decisions about which of the recommended tools and approaches to implement and scale-up. The test characteristics (e.g. sensitivity and specificity) of the tools alone are not a sufficient basis on which to make these decisions as policymakers need to also consider the best combination of tools, whether the new tools should complement or replace existing diagnostics and who should be tested. Diagnostic strategies need dovetailing to different epidemiology and structural resource constraints (e.g. existing diagnostic pathways, human resources and laboratory capacity). We propose operational modelling to assist with these complex decisions. Projections of patient, health system and cost impacts are essential and operational modelling of the relevant elements of the health system could provide these projections and support rational decisions. We demonstrate how the technique of operational modelling applied in the developing world to support decisions on diagnostics for tuberculosis, could in a parallel way, provide useful insights to support implementation of appropriate diagnostic innovations for parasitic diseases.

  13. Clinical utility of microRNA-378 as early diagnostic biomarker of human cancers: a meta-analysis of diagnostic test

    PubMed Central

    Li, Zhan-Zhan; Shen, Liang-Fang; Li, Yan-Yan; Chen, Peng; Chen, Li-Zhang

    2016-01-01

    A meta-analysis was performed to evaluate the diagnostic value of miR-378 for detecting human cancers. Systematic electronic searches were conducted in PubMed, Web of Science, Embase, China National Knowledge Infrastructure, and Wanfang from the inception to January 15, 2016. We used the bivariate mixed effects models to estimate the combined sensitivity, specificity, PLRs (positive likelihood ratios), NLR (negative likelihood ratios), DORs (diagnostic odds ratios) and their 95% CI (confidence intervals) for assessing the diagnostic performance of miR-378 for cancers. Twelve studies were included in the meta-analysis, with a total number of 1172 cancer patients and 809 health controls. The overall estimated sensitivity and specificity were 0.75 and 0.74. The pooled PLR was 2.91, NLR was 0.34, DOR was 8.50, and AUC (Area Under the Curve) was 0.81. The subgroup analyses suggested that AUC for plasma-based is higher than serum-based. The overall diagnostic values of miR-378 in the present meta-analyses are moderate accurate for human cancers; The source of specimen has an effect on the diagnostic accuracy. The diagnostic value of serum-based was higher than that of plasma-based. PMID:27448977

  14. Implementation of Rapid Molecular Infectious Disease Diagnostics: the Role of Diagnostic and Antimicrobial Stewardship.

    PubMed

    Messacar, Kevin; Parker, Sarah K; Todd, James K; Dominguez, Samuel R

    2017-03-01

    New rapid molecular diagnostic technologies for infectious diseases enable expedited accurate microbiological diagnoses. However, diagnostic stewardship and antimicrobial stewardship are necessary to ensure that these technologies conserve, rather than consume, additional health care resources and optimally affect patient care. Diagnostic stewardship is needed to implement appropriate tests for the clinical setting and to direct testing toward appropriate patients. Antimicrobial stewardship is needed to ensure prompt appropriate clinical action to translate faster diagnostic test results in the laboratory into improved outcomes at the bedside. This minireview outlines the roles of diagnostic stewardship and antimicrobial stewardship in the implementation of rapid molecular infectious disease diagnostics.

  15. A weighted generalized score statistic for comparison of predictive values of diagnostic tests.

    PubMed

    Kosinski, Andrzej S

    2013-03-15

    Positive and negative predictive values are important measures of a medical diagnostic test performance. We consider testing equality of two positive or two negative predictive values within a paired design in which all patients receive two diagnostic tests. The existing statistical tests for testing equality of predictive values are either Wald tests based on the multinomial distribution or the empirical Wald and generalized score tests within the generalized estimating equations (GEE) framework. As presented in the literature, these test statistics have considerably complex formulas without clear intuitive insight. We propose their re-formulations that are mathematically equivalent but algebraically simple and intuitive. As is clearly seen with a new re-formulation we presented, the generalized score statistic does not always reduce to the commonly used score statistic in the independent samples case. To alleviate this, we introduce a weighted generalized score (WGS) test statistic that incorporates empirical covariance matrix with newly proposed weights. This statistic is simple to compute, always reduces to the score statistic in the independent samples situation, and preserves type I error better than the other statistics as demonstrated by simulations. Thus, we believe that the proposed WGS statistic is the preferred statistic for testing equality of two predictive values and for corresponding sample size computations. The new formulas of the Wald statistics may be useful for easy computation of confidence intervals for difference of predictive values. The introduced concepts have potential to lead to development of the WGS test statistic in a general GEE setting.

  16. An electronic thesaurus of Evidence Based Laboratory Medicine hematological and biochemical diagnostic tests.

    PubMed

    Dorizzi, R M; Maconi, M; Giavarina, D; Loza, G; Aman, M; Moreira, J; Bisoffi, Z; Gennuso, C

    2009-10-01

    The adoption of Evidence Based Laboratory Medicine (EBLM) has been hampered until today by the lack of effective tools. The SIMeL EBLM e-Thesaurus (on-line Repertoire of the diagnostic effectiveness of the laboratory, radiology and cardiology test) provides a useful support to clinical laboratory professionals and to clinicians for the interpretation of the diagnostic tests. The e-Thesaurus is an application developed using Microsoft Active Server Pages technology and carried out with Web Server Microsoft Internet Information Server and is available at the SIMeL website using a browser running JavaScript scripts (Internet Explorer is recommended). It contains a database (in Italian, English and Spanish) of the sensitivity and specificity (including the 95% confidence interval), the positive and negative likelihood ratios, the Diagnostic Odds Ratio and the Number Needed to Diagnose of more than 2000 diagnostic (most laboratory but also cardiology and radiology) tests. The e-Thesaurus improves the previous SIMeL paper and CD Thesaurus; its main features are a three languages search and a continuous and an easy updating capability.

  17. Diagnostic models of the pre-test probability of stable coronary artery disease: A systematic review

    PubMed Central

    He, Ting; Liu, Xing; Xu, Nana; Li, Ying; Wu, Qiaoyu; Liu, Meilin; Yuan, Hong

    2017-01-01

    A comprehensive search of PubMed and Embase was performed in January 2015 to examine the available literature on validated diagnostic models of the pre-test probability of stable coronary artery disease and to describe the characteristics of the models. Studies that were designed to develop and validate diagnostic models of pre-test probability for stable coronary artery disease were included. Data regarding baseline patient characteristics, procedural characteristics, modeling methods, metrics of model performance, risk of bias, and clinical usefulness were extracted. Ten studies involving the development of 12 models and two studies focusing on external validation were identified. Seven models were validated internally, and seven models were validated externally. Discrimination varied between studies that were validated internally (C statistic 0.66-0.81) and externally (0.49-0.87). Only one study presented reclassification indices. The majority of better performing models included sex, age, symptoms, diabetes, smoking, and hyperlipidemia as variables. Only two diagnostic models evaluated the effects on clinical decision making processes or patient outcomes. Most diagnostic models of the pre-test probability of stable coronary artery disease have had modest success, and very few present data regarding the effects of these models on clinical decision making processes or patient outcomes. PMID:28355366

  18. Diagnostic models of the pre-test probability of stable coronary artery disease: A systematic review.

    PubMed

    He, Ting; Liu, Xing; Xu, Nana; Li, Ying; Wu, Qiaoyu; Liu, Meilin; Yuan, Hong

    2017-03-01

    A comprehensive search of PubMed and Embase was performed in January 2015 to examine the available literature on validated diagnostic models of the pre-test probability of stable coronary artery disease and to describe the characteristics of the models. Studies that were designed to develop and validate diagnostic models of pre-test probability for stable coronary artery disease were included. Data regarding baseline patient characteristics, procedural characteristics, modeling methods, metrics of model performance, risk of bias, and clinical usefulness were extracted. Ten studies involving the development of 12 models and two studies focusing on external validation were identified. Seven models were validated internally, and seven models were validated externally. Discrimination varied between studies that were validated internally (C statistic 0.66-0.81) and externally (0.49-0.87). Only one study presented reclassification indices. The majority of better performing models included sex, age, symptoms, diabetes, smoking, and hyperlipidemia as variables. Only two diagnostic models evaluated the effects on clinical decision making processes or patient outcomes. Most diagnostic models of the pre-test probability of stable coronary artery disease have had modest success, and very few present data regarding the effects of these models on clinical decision making processes or patient outcomes.

  19. The Status of Spectral EEG Abnormality as a Diagnostic Test for Schizophrenia

    PubMed Central

    Boutros, Nash N.; Arfken, Cynthia; Galderisi, Silvana; Warrick, Joshua; Pratt, Garrett; Iacono, William

    2008-01-01

    Objective A literature review was conducted to ascertain whether or not EEG spectral abnormalities are consistent enough to warrant additional effort towards developing them into a clinical diagnostic test for schizophrenia. Methods Fifty three papers met criteria for inclusion into the review and 15 were included in a meta-analysis of the degree of significance of EEG deviations as compared to healthy controls. Studies were classified based on a 4-step approach based on guidelines for evaluating the clinical usefulness of a diagnostic test. Results Our review and meta-analysis revealed that most of the abnormalities are replicated in the expected directions with the most consistent results related to the increased preponderance of slow rhythms in schizophrenia patients. This effect remained consistent in un-medicated patients. Only a small number of studies provided data on the sensitivity and specificity of the findings in differentiating among the psychiatric disorders that frequently appear on the same differential diagnostic list as schizophrenia (step 3 studies). No multicenter studies using standardized assessment criteria were found (step 4 studies). Conclusions Additional Step 3 and Step 4 studies are needed to draw conclusions on the usefulness of EEG spectral abnormalities as a diagnostic test for schizophrenia PMID:18160260

  20. Diagnostic Accuracy of Obstructive Airway Adult Test for Diagnosis of Obstructive Sleep Apnea

    PubMed Central

    Gasparini, Giulio; Vicini, Claudio; De Benedetto, Michele; Salamanca, Fabrizio; Sorrenti, Giovanni; Romandini, Mario; Bosi, Marcello; Saponaro, Gianmarco; Foresta, Enrico; Laforì, Andreina; Meccariello, Giuseppe; Bianchi, Alessandro; Toraldo, Domenico Maurizio; Campanini, Aldo; Montevecchi, Filippo; Rizzotto, Grazia; Cervelli, Daniele; Moro, Alessandro; Arigliani, Michele; Gobbi, Riccardo; Pelo, Sandro

    2015-01-01

    Rationale. The gold standard for the diagnosis of Obstructive Sleep Apnea (OSA) is polysomnography, whose access is however reduced by costs and limited availability, so that additional diagnostic tests are needed. Objectives. To analyze the diagnostic accuracy of the Obstructive Airway Adult Test (OAAT) compared to polysomnography for the diagnosis of OSA in adult patients. Methods. Ninety patients affected by OSA verified with polysomnography (AHI ≥ 5) and ten healthy patients, randomly selected, were included and all were interviewed by one blind examiner with OAAT questions. Measurements and Main Results. The Spearman rho, evaluated to measure the correlation between OAAT and polysomnography, was 0.72 (p < 0.01). The area under the ROC curve (95% CI) was the parameter to evaluate the accuracy of the OAAT: it was 0.91 (0.81–1.00) for the diagnosis of OSA (AHI ≥ 5), 0.90 (0.82–0.98) for moderate OSA (AHI ≥ 15), and 0.84 (0.76–0.92) for severe OSA (AHI ≥ 30). Conclusions. The OAAT has shown a high correlation with polysomnography and also a high diagnostic accuracy for the diagnosis of OSA. It has also been shown to be able to discriminate among the different degrees of severity of OSA. Additional large studies aiming to validate this questionnaire as a screening or diagnostic test are needed. PMID:26636102

  1. A diagnostic one-step real-time reverse transcription polymerase chain reaction method for accurate detection of influenza virus type A

    PubMed Central

    Behzadi, Mohammad Amin; Alborzi, Abdolvahab

    2016-01-01

    Introduction Influenza A is known as a public health concern worldwide. In this study, a novel one-step real-time reverse transcription polymerase chain reaction (rtRT-PCR) assay was designed and optimized for the detection of influenza A viruses. Material and methods The primers and probe were designed based on the analysis of 90 matrix nucleotide sequence data of influenza type A subtypes from the GenBank database of the National Center for Biotechnology Information (NCBI). The influenza virus A/Tehran/5652/2010 (H1N1 pdm09) was used as a reference. The rtRT-PCR assay was optimized, compared with that of the World Health Organization (WHO), and its analytical sensitivity, specificity and reproducibility were evaluated. In total, 64 nasopharyngeal swabs from patients with influenza-like illness (ILI) and 41 samples without ILI symptoms were tested for the virus, using conventional cell culture, direct immunofluorescence antibody (DFA) methods, and one-step rtRT-PCR with the designed primer set and probe and the WHO’s. Results The optimized assay results were similar to the WHO’s. The optimized assay results were similar to WHO’s, with non-significant differences for 10–103 copies of viral RNA/reaction (p > 0.05). It detected 10 copies of viral RNA/reaction with high reproducibility and no cross reactivity with other respiratory viruses. A specific cytopathic effect was observed in 6/64 (9.37%) of the ILI group using conventional culture and DFA staining methods; however, it was not seen in non-ILI. Also, the results of our assay and the WHO’s were similar to those of viral isolation and DFA staining. Conclusions Given the high specificity, sensitivity and reproducibility of this novel assay, it can serve as a reliable diagnostic tool for the detection of influenza A viruses in clinical specimens and lab experiments. PMID:27904520

  2. AD8 Informant Questionnaire for Cognitive Impairment: Pragmatic Diagnostic Test Accuracy Study.

    PubMed

    Larner, A J

    2015-09-01

    The diagnostic accuracy of the AD8 informant questionnaire for cognitive impairment was assessed in patients referred to a dedicated memory clinic. This pragmatic prospective study of consecutive referrals attending with an informant who completed AD8 (n = 212) lasted 12 months. Diagnosis used standard clinical diagnostic criteria for dementia and mild cognitive impairment as reference standard (prevalence of cognitive impairment = 0.62). The AD8 proved acceptable to informants, was quick, and easy to use. Using the cutoff of ≥2/8, AD8 was highly sensitive (0.97) for diagnosis of cognitive impairment but specificity was poor (0.17). Combining AD8 with either the Mini-Mental State Examination or the Six-Item Cognitive Impairment Test showed little additional diagnostic benefit. In conclusion, AD8 is very sensitive for cognitive impairment in a memory clinic but specificity may be inadequate.

  3. The development of a post-test diagnostic system for rocket engines

    NASA Technical Reports Server (NTRS)

    Zakrajsek, June F.

    1991-01-01

    An effort was undertaken by NASA to develop an automated post-test, post-flight diagnostic system for rocket engines. The automated system is designed to be generic and to automate the rocket engine data review process. A modular, distributed architecture with a generic software core was chosen to meet the design requirements. The diagnostic system is initially being applied to the Space Shuttle Main Engine data review process. The system modules currently under development are the session/message manager, and portions of the applications section, the component analysis section, and the intelligent knowledge server. An overview is presented of a rocket engine data review process, the design requirements and guidelines, the architecture and modules, and the projected benefits of the automated diagnostic system.

  4. Overview of the impact of noninvasive prenatal testing on diagnostic procedures.

    PubMed

    Warsof, Steven L; Larion, Sebastian; Abuhamad, Alfred Z

    2015-10-01

    Noninvasive prenatal testing (NIPT) has had a profound influence in the field of prenatal diagnosis since the 1997 discovery of cell-free fetal DNA in maternal blood. Research has progressed rapidly, with clinical data supporting laboratory studies showing that NIPT is highly sensitive and specific for fetal aneuploidy, resulting in marked uptake in the high-risk patient population. The superior accuracy of NIPT compared with conventional screening methods has led to significant decreases in the number of invasive diagnostic procedures, in addition to a concomitant decrease in the number of procedure-related fetal losses. Yet, NIPT has been described as a 'disruptive innovation' due to the considerable changes the technology has commanded on current prenatal screening and diagnostic practices. This review summarizes both institutional and global experience with NIPT uptake, its effect on reducing diagnostic invasive procedures, and the unique challenges that reduced procedural volume may have on physician and trainee proficiency, cytogenetic laboratories, and neonatal outcome.

  5. Evaluation of Diagnostic Tests Using Information Theory for Multi-Class Diagnostic Problems and its Application for the Detection of Occlusal Caries Lesions

    PubMed Central

    Arslan, Umut; Karaağaoğlu, Ergun; Özkan, Gökhan; Kanlı, Aydan

    2014-01-01

    Background: Several methods are available to evaluate the performance of the tests when the purpose of the diagnostic test is to discriminate between two possible disease states. However multi-class diagnostic problems frequently appear in many areas of medical science. Hence, there is a need for methods which will enable us to characterize the accuracy of diagnostic tests when there are more than two possible disease states. Aims: To show that two information theory measures, information content (IC) and proportional reduction in diagnostic uncertainty (PRDU), can be used for the evaluation of the performance of diagnostic tests for multi-class diagnostic problems that may appear in different areas of medical science. Study Design: Diagnostic accuracy study. Methods: Sixty freshly extracted permanent human molar and pre-molar teeth suspected to have occlusal caries lesions were selected for the study and were assessed by two experienced examiners. Each examiner performed two evaluations. Histological examination was used as the gold standard. The scores of the histological examination were defined as sound (n=11), enamel caries (n=22) and dentin caries (n=27). Diagnostic performance of i) visual inspection, ii) radiography, iii) laser fluorescence (LF) and iv) micro-computed tomography (M-CT) caries detection methods was evaluated by calculating IC and PRDU. Results: Micro-computed tomography examination was the best method among the diagnostic techniques for the diagnosis of occlusal caries in terms of both IC and PRDU. M-CT examination supplied the maximum diagnostic information about the diagnosis of occlusal caries in the first (IC: 1.056; p<0.05), (PRDU: 70.5%) and second evaluation (IC: 1.105; p<0.05), (PRDU: 73.8%) for the first examiner. M-CT examination was the best method among the diagnostic techniques for the second examiner in both the first (IC:1.105; p<0.05), (PRDU:73.8%) and second evaluation (IC:1.061; p<0.05), (PRDU:70.8%). IC and PRDU were

  6. Clinical Predictors of Diagnostic Testing Utility in the Initial Evaluation of Chronic Kidney Disease

    PubMed Central

    Mendu, Mallika L.; Lundquist, Andrew; Aizer, Ayal A.; Leaf, David E.; Robinson, Emily; Steele, David J.R.; Waikar, Sushrut S.

    2016-01-01

    Aim No evidence-based approach to the evaluation of CKD has been established. We sought to identify clinical criteria to guide a rational diagnostic approach for the initial evaluation of CKD. Methods We conducted a retrospective cohort study of 1,487 patients presenting for initial evaluation of CKD over three years (1/2010–1/2013) to academic nephrology clinics. We utilized the electronic medical record to determine tests ordered, abnormal results, and testing that affected diagnosis and/or management. Diagnostic and management yield of testing was defined as the percentage of tests that affected diagnosis and/or management. High yield for a given test was defined as an increased likelihood of the test affecting diagnosis and/or management. Results We identified clinical criteria predictive of high yield for paraprotein-related testing (one of the following: history of monoclonal disease, high risk of CKD progression, hypercalcemia or hemoglobin <10.6), and clinical criteria predictive of high yield for glomerulonephritis testing (one of the following: abnormal urine sediment, 3+ or greater hematuria or proteinuria >500mg/gm). A prior history of hydronephrosis and renal artery stenosis was predictive of high yield of abnormal renal ultrasound. Higher yield of testing was associated with higher risk progression categories for ANA, SPEP, urine sediment, calcium, PTH, hemoglobin, iron, and ferritin. We estimate that initial CKD evaluation costs range from $28 to $109 million/year in US-Medicare expenditure. Conclusion Numerous tests without significant clinical utility are obtained in initial CKD evaluation. Identifying criteria that can guide diagnostic testing may lead to a more informed and cost-effective approach to evaluation. PMID:26610178

  7. Fibre Diffraction Analysis of Skin Offers a Very Early and Extremely Accurate Diagnostic Test for Prostate Cancer

    DOE PAGES

    James, Veronica J.; O’Malley Ford, Judith M.

    2014-01-01

    Double blind analysis of a batch of thirty skin tissue samples from potential prostate cancer sufferers correctly identified all “control” patients, patients with high and low grade prostate cancers, the presence of benign prostate hyperplasia (BPH), perineural invasions, and the one lymphatic invasion. Identification was by analysis of fibre diffraction patterns interpreted using a schema developed from observations in nine previous studies. The method, schema, and specific experiment results are reported in this paper, with some implications then drawn.

  8. Diagnostic validation of three test methods for detection of cyprinid herpesvirus 3 (CyHV-3).

    PubMed

    Clouthier, Sharon C; McClure, Carol; Schroeder, Tamara; Desai, Megan; Hawley, Laura; Khatkar, Sunita; Lindsay, Melissa; Lowe, Geoff; Richard, Jon; Anderson, Eric D

    2017-03-06

    Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of koi herpesvirus disease in koi and common carp. The disease is notifiable to the World Organisation for Animal Health. Three tests-quantitative polymerase chain reaction (qPCR), conventional PCR (cPCR) and virus isolation by cell culture (VI)-were validated to assess their fitness as diagnostic tools for detection of CyHV-3. Test performance metrics of diagnostic accuracy were sensitivity (DSe) and specificity (DSp). Repeatability and reproducibility were measured to assess diagnostic precision. Estimates of test accuracy, in the absence of a gold standard reference test, were generated using latent class models. Test samples originated from wild common carp naturally exposed to CyHV-3 or domesticated koi either virus free or experimentally infected with the virus. Three laboratories in Canada participated in the precision study. Moderate to high repeatability (81 to 99%) and reproducibility (72 to 97%) were observed for the qPCR and cPCR tests. The lack of agreement observed between some of the PCR test pair results was attributed to cross-contamination of samples with CyHV-3 nucleic acid. Accuracy estimates for the PCR tests were 99% for DSe and 93% for DSp. Poor precision was observed for the VI test (4 to 95%). Accuracy estimates for VI/qPCR were 90% for DSe and 88% for DSp. Collectively, the results show that the CyHV-3 qPCR test is a suitable tool for surveillance, presumptive diagnosis and certification of individuals or populations as CyHV-3 free.

  9. Long-Pulse Integrator Testing with DIII-D Magnetic Diagnostics

    NASA Astrophysics Data System (ADS)

    Slobodov, Ilia; Miller, Kenneth; Ziemba, Timothy; Prager, James; Carscadden, John; Hanson, Eric

    2016-10-01

    Eagle Harbor Technologies (EHT), Inc. has developed a high-gain integrator for magnetic diagnostics that meets ITER specifications including integration time and integration error limits. EHT has conducted testing of this long-pulse integrator at DIII-D with existing DIII-D magnetic probes. The EHT long-pulse integrator was operated for several hours up to a full day. During a single period of EHT integrator operation, DIII-D was pulsed multiple times. The multiple pulses from the DIII-D magnetic diagnostics can be clearly resolved in the integrator signal output. The results are compared to DIII-D measurements. EHT also operated the long pulse integrator in High Dynamic Range Mode (HDRM), which effectively allows for a dramatic increase in measurement bit depth for higher resolution signal acquisition with the same diagnostic and digitizers presently available on DIII-D. Additionally, EHT has tested a new microprocessor and FPGA-based digitizer, which can be included on the integrator PCB, for a single board magnetic diagnostic solution.

  10. 9 CFR 130.17 - User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for other veterinary... FEES USER FEES § 130.17 User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or at authorized sites. (a) User fees for veterinary diagnostics tests performed at...

  11. 9 CFR 130.16 - User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at authorized sites. 130.16 Section 130.16 Animals... USER FEES § 130.16 User fees for veterinary diagnostic serology tests performed at NVSL...

  12. An Overview of Models of Speaking Performance and Its Implications for the Development of Procedural Framework for Diagnostic Speaking Tests

    ERIC Educational Resources Information Center

    Zhao, Zhongbao

    2013-01-01

    This paper aims at developing a procedural framework for the development and validation of diagnostic speaking tests. The researcher reviews the current available models of speaking performance, analyzes the distinctive features and then points out the implications for the development of a procedural framework for diagnostic speaking tests. On…

  13. 30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and diagnostic tests? 250.523 Section 250.523 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations Casing Pressure Management § 250.523 How... diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last...

  14. Juvenile retinoschisis: a model for molecular diagnostic testing of X-linked ophthalmic disease.

    PubMed Central

    Sieving, P A; Yashar, B M; Ayyagari, R

    1999-01-01

    BACKGROUND AND PURPOSE: X-linked juvenile retinoschisis (RS) provides a starting point to define clinical paradigms and understand the limitations of diagnostic molecular testing. The RS phenotype is specific, but the broad severity range is clinically confusing. Molecular diagnostic testing obviates unnecessary examinations for boys at-risk and identifies carrier females who otherwise show no clinical signs. METHODS: The XLRS1 gene has 6 exons of 26-196 base-pair size. Each exon is amplified by a single polymerase chain reaction and then sequenced, starting with exons 4 through 6, which contain mutation "hot spots." RESULTS: The 6 XLRS1 exons are sequenced serially. If alterations are found, they are compared with mutations in our > 120 XLRS families and with the > 300 mutations reported worldwide. Point mutations, small deletions, or rearrangements are identified in nearly 90% of males with a clinical diagnosis of RS. XLRS1 has very few sequence polymorphisms. Carrier-state testing produces 1 of 3 results: (1) positive, in which the woman has the same mutation as an affected male relative or known in other RS families; (2) negative, in which she lacks the mutation of her affected male relative; and (3) uninformative, in which no known mutation is identified or no information exists about the familial mutation. CONCLUSIONS: Molecular RS screening is an effective diagnostic tool that complements the clinician's skills for early detection of at-risk males. Useful outcomes of carrier testing depend on several factors: (1) a male relative with a clear clinical diagnosis; (2) a well-defined inheritance pattern; (3) high disease penetrance; (4) size and organization of the gene; and (5) the types of disease-associated mutations. Ethical questions include molecular diagnostic testing of young at-risk females before the age of consent, the impact of this information on the emotional health of the patient and family, and issues of employability and insurance coverage

  15. Forensic science does not start in the lab: the concept of diagnostic field tests.

    PubMed

    Almog, Joseph

    2006-11-01

    An attempt to improve an analytical system can focus either on the actual processing or on the input. In forensic science, much emphasis has been placed on improving laboratory procedures, as though the input is already the best that can be obtained. Means of improving the basic input have gained much less attention. Yet, it must be agreed that even the best laboratory cannot gain from an item more than has been contained in it when it arrived from the field. The detection of latent materials at the crime scene by physical or chemical techniques and the diagnostic examination of material already discovered belong to the concept of diagnostic field tests. This group also includes "mapping" for the presence of certain materials, such as latent fingerprints through the distribution of amino acids on the surface. These tests are conducted outside the laboratory, without sophisticated instrumentation, at the crime scene, the suspect's home, or elsewhere. A significant advantage of the use of diagnostic field tests is the ability to deal with "dissipating evidence" such as gunshot residue or explosive traces on the hands of suspects. If time is lost, there is a risk of losing such evidence, which is liable to deteriorate rapidly. In my presentation, I will discuss older and some newly developed forensic field tests, with specific emphasis on the Israeli experience.

  16. Analysis of diagnostic testing of Gladys McCall Well No. 1

    SciTech Connect

    Riney, T.D.; Garg, S.K.

    1991-12-01

    Gladys McCall Well No. 1 was flow tested from 1983 to 1987, underwent long-term pressure buildup testing from October 1987 to October 1991, and has recently been re-entered for final diagnostic testing. The combination of a very large, poorly defined reservoir with data from only a single well has required that the testing be carried out over an unusually long time period for an understanding of the pressure maintenance mechanisms to be developed. Ongoing diagnostic testing of the well has been undertaken by DOE to help resolve questions that arose during the analysis of the test data from the eight year depletion and recovery testing. A rather complete summary of the synthesis, correlation and analysis of the earlier test data has recently been published (Riney, 1991.) and is included in this report as an Appendix. Figure 1 (an update of Figure 9 in the Appendix) includes the final pressure buildup data in the comparison with the earlier reservoir simulation model. During October 1991 the Gladys McCall well was flowed twice as part of the diagnostic testing. On October 1 flow was started to clean out the well and to perform a spinner survey to determine the fluid entry distribution across the perforated interval of Sand 8. The spinner log was run on October 2 with the well producing at a constant rate of {approx} 4800 stb/d. Total production during the October 1-2 test period was 5954 stb. The second flow was from October 10 to 14 to obtain downhole pressure transient data to determine if the transmissivity (kh product) of Sand 8 had changed during the four-year shutin period (October 1987 to October 1991). The total production during the four day constant-rate (5958 stb/d) drawdown test of October 10-14 was 23,850 stb. Eaton Operating Co. and Institute of Gas Technology are continuing with the diagnostic testing; entry and pressure measurements in two overlaying sands (2 and 4) are planned. Since neither time nor funds are sufficient to complete the Gladys Mc

  17. Low specificities of HIV diagnostic tests caused by Trypanosoma brucei gambiense sleeping sickness.

    PubMed

    Lejon, V; Ngoyi, D Mumba; Ilunga, M; Beelaert, G; Maes, I; Büscher, P; Fransen, K

    2010-08-01

    The accuracy of diagnostic tests for HIV in patients with tropical infections is poorly documented. Human African trypanosomiasis (HAT) is characterized by a polyclonal B-cell activation, constituting a risk for false-positive reactions to diagnostic tests, including HIV tests. A retrospective study of the accuracy of HIV diagnostic tests was performed with 360 human African HAT patients infected with Trypanosoma brucei gambiense before treatment and 163 T. b. gambiense-infected patients 2 years after successful treatment in Mbuji Mayi, East Kasai, Democratic Republic of the Congo. The sensitivities, specificities, and positive predictive values (PPVs) of individual tests and algorithms consisting of 3 rapid tests were determined. The sensitivity of all tests was 100% (11/11). The low specificity (96.3%, 335/348) and PPV (45.8%, 11/24) of a classical seroconfirmation strategy (Vironostika enzyme-linked immunosorbent assay [ELISA] followed by line immunoassay) complicated the determination of HIV status, which had to be determined by PCR. The specificities of the rapid diagnostic tests were 39.1% for Determine (136/348); 85.3 to 92.8% (297/348 to 323/348) for Vikia, ImmunoFlow, DoubleCheck, and Bioline; and 96.6 to 98.3% (336/348 to 342/348) for Uni-Gold, OraQuick, and Stat-Pak. The specificity of Vironostika was 67.5% (235/348). PPVs ranged between 4.9 and 64.7%. Combining 3 different rapid tests resulted in specificities of 98.3 to 100% (342/348 to 348/348) and PPVs of 64.7 to 100% (11/17 to 11/11). For cured HAT patients, specificities were significantly higher for Vironostika, Determine, Uni-Gold, and ImmunoFlow. T. b. gambiense infection decreases the specificities of antibody detection tests for HIV diagnosis. Unless tests have been validated for interference with HAT, HIV diagnosis using classical algorithms in untreated HAT patients should be avoided. Specific, validated combinations of 3 HIV rapid tests can increase specificity.

  18. Practice Bulletin No. 162 Summary: Prenatal Diagnostic Testing for Genetic Disorders.

    PubMed

    2016-05-01

    Prenatal genetic diagnostic testing is intended to determine, with as much certainty as possible, whether a specific genetic disorder or condition is present in the fetus. In contrast, prenatal genetic screening is designed to assess whether a patient is at increased risk of having a fetus affected by a genetic disorder. Originally, prenatal genetic testing focused primarily on Down syndrome (trisomy 21), but now it is able to detect a broad range of genetic disorders. Although it is necessary to perform amniocentesis or chorionic villus sampling (CVS) to definitively diagnose most genetic disorders, in some circumstances, fetal imaging with ultrasonography, echocardiography, or magnetic resonance imaging may be diagnostic of a particular structural fetal abnormality that is suggestive of an underlying genetic condition.The objective of prenatal genetic testing is to detect health problems that could affect the woman, fetus, or newborn and provide the patient and her obstetrician-gynecologist or other obstetric care provider with enough information to allow a fully informed decision about pregnancy management. Prenatal genetic testing cannot identify all abnormalities or problems in a fetus, and any testing should be focused on the individual patient's risks, reproductive goals, and preferences. It is important that patients understand the benefits and limitations of all prenatal screening and diagnostic testing, including the conditions for which tests are available and the conditions that will not be detected by testing. It also is important that patients realize that there is a broad range of clinical presentations, or phenotypes, for many genetic disorders and that results of genetic testing cannot predict all outcomes. Prenatal genetic testing has many benefits, including reassuring patients when results are normal, identifying disorders for which prenatal treatment may provide benefit, optimizing neonatal outcomes by ensuring the appropriate location for

  19. Beam Diagnostics Report for the Thermal Test Conducted on 3/9/2016

    SciTech Connect

    Holloway, Michael Andrew; Dalmas, Dale Allen

    2016-08-11

    The thermal test OTR data revealed several issues with the beam focus and the target window itself. The oxidation of the target window and the prominence of a scratch across the center of the window makes it impossible to accurately measure the beam profile and size.

  20. ParaSight-F rapid manual diagnostic test of Plasmodium falciparum infection.

    PubMed Central

    Uguen, C.; Rabodonirina, M.; De Pina, J. J.; Vigier, J. P.; Martet, G.; Maret, M.; Peyron, F.

    1995-01-01

    The ParaSight(R)-F test is a qualitative diagnostic test of Plasmodium falciparum, which is based on the detection by a monoclonal antibody of a species-specific soluble antigen (histidine-rich protein (HRP-II)) in whole blood and which can be performed without special equipment. A visual reading is given by a polyclonal antibody coupled with dye-loaded liposomes; when positive, a pink line appears. The test has been compared with microscopic examination of thin blood smears and with Quantitative Buffy Coat malaria test (QBC(R) in a single-blind study. A total of 358 patients who had returned to France from malarial areas and consulted their doctor with symptoms or for a routine examination were enrolled in the study; 33 of them were found to have a falciparum malaria infection by the diagnostic test. On the day of consultation, the specificity of the ParaSight(R)-F test was 99% and its sensitivity 94%. The follow-up of infected patients after treatment showed that the test became negative later than the other reference tests. There was no correlation between antigen persistence and the intensity of the ParaSight(R)-F signal or circulating parasitaemia. No cross-reaction was noted for seven malaria cases due to other Plasmodium species. The test was performed quickly (10 tests in 20 minutes), was easy to read, and required minimal space. For cases of imported malaria, the test's specificity and low threshold for detection could make it a valuable adjunct test. However, in its present form, it cannot replace microscopic techniques which are species-specific and quantitative. In endemic areas, the test seems to be very promising by its results and ease of use according to published field studies. Images Fig. 1 Fig. 2 PMID:8846490

  1. Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing

    PubMed Central

    Tsalatsanis, Athanasios; Hozo, Iztok; Kumar, Ambuj; Djulbegovic, Benjamin

    2015-01-01

    Dual Processing Theories (DPT) assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive) and type 2 (deliberative). Based on DPT we have derived a Dual Processing Model (DPM) to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called “threshold probability” at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT) and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today’s clinical practice. PMID:26244571

  2. Impact of clinical awareness and diagnostic tests on the underdiagnosis of Clostridium difficile infection.

    PubMed

    Alcalá, L; Reigadas, E; Marín, M; Martín, A; Catalán, P; Bouza, E

    2015-08-01

    A multicenter study of Clostridium difficile infection (CDI) performed during 2008 in Spain revealed that two of every three episodes went undiagnosed or were misdiagnosed owing to nonsensitive diagnostic tests or lack of clinical suspicion and request. Since then, efforts have been made to improve the diagnostic tests used by laboratories and to increase the awareness of this disease among both clinicians and microbiologists. Our objective was to evaluate the impact of these efforts by assessing the current magnitude of underdiagnosis of CDI in Spain using two point-prevalence studies performed on one day each in January and July of 2013. A total of 111 Spanish laboratories selected all unformed stool specimens received for microbiological diagnosis on these days, and toxigenic culture was performed at a central reference laboratory. Toxigenic isolates were characterized both pheno- and genotypically. The reference laboratory detected 103 episodes of CDI in patients aged 2 years or more. Half (50.5 %) of the episodes were not diagnosed in the participating laboratories, owing to insensitive diagnostic tests (15.5 %) or the lack of clinical suspicion and request (35.0 %). The main ribotypes were 014, 078/126, 001/072, and 106. Ribotype 027 caused 2.9 % of all cases. Despite all the interventions undertaken, CDI remains a highly neglected disease because of the lack of sensitive diagnostic tests in some institutions and, especially, the absence of clinical suspicion, mainly in patients with community-associated CDI. Toxigenic C. difficile should be routinely sought in unformed stools sent for microbiological diagnosis, regardless of their origin.

  3. A Novel Field Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis

    DTIC Science & Technology

    2015-10-01

    AWARD NUMBER: W81XWH-14-2-0196 TITLE: A Novel Field-Deployable Point-of- Care Diagnostic Test for Cutaneous Leishmaniasis PRINCIPAL INVESTIGATOR...Annual 3. DATES COVERED (From - To) 30 Sept 2014- 29 Sept 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER A Novel Field-Deployable Point-of- Care ...have high sensitivity and specificity to diagnose cutaneous leishmaniasis at the point of care in a field setting. Study Design. We propose to utilize

  4. Diagnostic testing in the context of high-value care: Incorporating prior probability

    PubMed Central

    Cardinal, Lucien

    2016-01-01

    This is the fifth article of a series on fundamental concepts in biostatistics and research. In this article, the author reviews the fundamental concepts in diagnostic testing, prior probability and predictive value, and how they relate to the concept of high-value care. The topics are discussed in common language with a minimum of jargon and mathematics. Emphasis is given to conceptual understanding. A companion article preceding this one focused on sensitivity and specificity. PMID:27987293

  5. Accurate detection of coronary artery disease by integrated analysis of the ST-segment depression/heart rate patterns during the exercise and recovery phases of the exercise electrocardiography test.

    PubMed

    Lehtinen, R; Sievänen, H; Viik, J; Turjanmaa, V; Niemelä, K; Malmivuo, J

    1996-11-01

    In this comparative cross-sectional study, we evaluated whether a novel computerized diagnostic variable, ST-segment depression/heart rate ST/HR analysis during both the exercise and postexercise recovery phases of the exercise electrocardiography (ECG) test, can detect coronary artery disease more accurately than methods using either exercise or recovery phase alone. The study population comprised 347 clinical patients referred for a routine bicycle exercise ECG test at Tampere University Hospital, Finland. Of these, 127 had angiographically proven coronary artery disease, whereas 13 had no coronary artery disease according to angiography, 18 had no perfusion defect according to technetium-99m sestamibi single-photon emission computed tomography, and 189 were clinically normal with respect to cardiac diseases. For each patient, the maximum values of the ST/HR hysteresis, ST/HR index, end-exercise ST depression, and recovery ST depression were determined from the Mason-Likar modification of the standard 12-lead exercise electrocardiogram [aVL, aVR, and V1 excluded]. The diagnostic performance of these continuous diagnostic variables was compared by means of receiver-operating characteristic analysis. The area under the receiver-operating characteristic curve of the ST/HR hysteresis was 89%, which was significantly larger than that of the end-exercise ST depression (76%, p < or = 0.0001), recovery ST depression (84%, p = 0.0063), or ST/HR index (83%, p = 0.0023), indicating superior diagnostic performance of the ST/HR hysteresis independent of the partition value selection. In conclusion, computerized analysis of the HR-adjusted ST depression pattern during the exercise phase, integrated with the HR-adjusted ST depression pattern during the recovery phase after exercise, can significantly improve the diagnostic performance and clinical utility of the exercise ECG test for the detection of coronary artery disease.

  6. Planning for Plume Diagnostics for Ground Testing of J-2X Engines at the SSC

    NASA Technical Reports Server (NTRS)

    SaintCyr, William W.; Tejwani, Gopal D.; McVay, Gregory P.; Langford, Lester A.; SaintCyr, William W.

    2010-01-01

    John C. Stennis Space Center (SSC) is the premier test facility for liquid rocket engine development and certification for the National Aeronautics and Space Administration (NASA). Therefore, it is no surprise that the SSC will play the most prominent role in the engine development testing and certification for the J-2X engine. The Pratt & Whitney Rocketdyne J-2X engine has been selected by the Constellation Program to power the Ares I Upper Stage Element and the Ares V Earth Departure Stage in NASA s strategy of risk mitigation for hardware development by building on the Apollo program and other lessons learned to deliver a human-rated engine that is on an aggressive development schedule, with first demonstration flight in 2010 and human test flights in 2012. Accordingly, J-2X engine design, development, test, and evaluation is to build upon heritage hardware and apply valuable experience gained from past development and testing efforts. In order to leverage SSC s successful and innovative expertise in the plume diagnostics for the space shuttle main engine (SSME) health monitoring,1-10 this paper will present a blueprint for plume diagnostics for various proposed ground testing activities for J-2X at SSC. Complete description of the SSC s test facilities, supporting infrastructure, and test facilities is available in Ref. 11. The A-1 Test Stand is currently being prepared for testing the J-2X engine at sea level conditions. The A-2 Test Stand is currently being used for testing the SSME and may also be used for testing the J-2X engine at sea level conditions in the future. Very recently, ground-breaking ceremony for the new A-3 rocket engine test stand took place at SSC on August 23, 2007. A-3 is the first large - scale test stand to be built at the SSC since the A and B stands were constructed in the 1960s. The A-3 Test Stand will be used for testing J-2X engines under vacuum conditions simulating high altitude operation at approximately 30,480 m (100,000 ft

  7. Personality Assessment in the Diagnostic Manuals: On Mindfulness, Multiple Methods, and Test Score Discontinuities.

    PubMed

    Bornstein, Robert F

    2015-01-01

    Recent controversies have illuminated the strengths and limitations of different frameworks for conceptualizing personality pathology (e.g., trait perspectives, categorical models), and stimulated debate regarding how best to diagnose personality disorders (PDs) in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.), and in other diagnostic systems (i.e., the International Classification of Diseases, the Psychodynamic Diagnostic Manual). In this article I argue that regardless of how PDs are conceptualized and which diagnostic system is employed, multimethod assessment must play a central role in PD diagnosis. By complementing self-reports with evidence from other domains (e.g., performance-based tests), a broader range of psychological processes are engaged in the patient, and the impact of self-perception and self-presentation biases can be better understood. By providing the assessor with evidence drawn from multiple modalities, some of which provide converging patterns and some of which yield divergent results, a multimethod assessment compels the assessor to engage this evidence more deeply. The mindful processing that ensues can help minimize the deleterious impact of naturally occurring information processing bias and distortion on the part of the clinician (e.g., heuristics, attribution errors), bringing greater clarity to the synthesis and integration of assessment data.

  8. Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms

    PubMed Central

    Twisk, Frank NM

    2015-01-01

    Although myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) are considered to be synonymous, the definitional criteria for ME and CFS define two distinct, partially overlapping, clinical entities. ME, whether defined by the original criteria or by the recently proposed criteria, is not equivalent to CFS, let alone a severe variant of incapacitating chronic fatigue. Distinctive features of ME are: muscle weakness and easy muscle fatigability, cognitive impairment, circulatory deficits, a marked variability of the symptoms in presence and severity, but above all, post-exertional “malaise”: a (delayed) prolonged aggravation of symptoms after a minor exertion. In contrast, CFS is primarily defined by (unexplained) chronic fatigue, which should be accompanied by four out of a list of 8 symptoms, e.g., headaches. Due to the subjective nature of several symptoms of ME and CFS, researchers and clinicians have questioned the physiological origin of these symptoms and qualified ME and CFS as functional somatic syndromes. However, various characteristic symptoms, e.g., post-exertional “malaise” and muscle weakness, can be assessed objectively using well-accepted methods, e.g., cardiopulmonary exercise tests and cognitive tests. The objective measures acquired by these methods should be used to accurately diagnose patients, to evaluate the severity and impact of the illness objectively and to assess the positive and negative effects of proposed therapies impartially. PMID:26140274

  9. Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms.

    PubMed

    Twisk, Frank Nm

    2015-06-26

    Although myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) are considered to be synonymous, the definitional criteria for ME and CFS define two distinct, partially overlapping, clinical entities. ME, whether defined by the original criteria or by the recently proposed criteria, is not equivalent to CFS, let alone a severe variant of incapacitating chronic fatigue. Distinctive features of ME are: muscle weakness and easy muscle fatigability, cognitive impairment, circulatory deficits, a marked variability of the symptoms in presence and severity, but above all, post-exertional "malaise": a (delayed) prolonged aggravation of symptoms after a minor exertion. In contrast, CFS is primarily defined by (unexplained) chronic fatigue, which should be accompanied by four out of a list of 8 symptoms, e.g., headaches. Due to the subjective nature of several symptoms of ME and CFS, researchers and clinicians have questioned the physiological origin of these symptoms and qualified ME and CFS as functional somatic syndromes. However, various characteristic symptoms, e.g., post-exertional "malaise" and muscle weakness, can be assessed objectively using well-accepted methods, e.g., cardiopulmonary exercise tests and cognitive tests. The objective measures acquired by these methods should be used to accurately diagnose patients, to evaluate the severity and impact of the illness objectively and to assess the positive and negative effects of proposed therapies impartially.

  10. Decentralized molecular diagnostic testing plan for pandemic influenza in the Ontario Public Health Laboratory system.

    PubMed

    Drews, Steven J; Majury, Anna; Jamieson, Frances; Riley, Garth; Mazzulli, Tony; Low, Donald E

    2008-01-01

    The Ontario Public Health Laboratories system (OPHL) is in the midst of a six-year plan to implement molecular tools for pandemic influenza diagnostics in one central and three regional public health laboratories. This plan has been formulated as a consequence of: (1) experiences gained through severe acute respiratory syndrome (SARS), and comments of the members of the Expert Panel on SARS and Infectious Disease Control (i.e., the Walker report); (2) a review of pandemic preparedness literature; (3) historical and epidemiologic discussions about previous pandemics; and (4) suggestions made by various pandemic working committees. The OPHL plan includes: (1) an aggressive restructuring of the overall molecular microbiology testing capacity of the OPHL; (2) the ability to shift influenza testing of samples between designated OPHL laboratories; and (3) the development of screening tools for pandemic influenza diagnostic tests. The authors believe that investing in increased molecular testing capacity for regional laboratories outside the greater Toronto area will be beneficial to the OPHL system whether or not an influenza pandemic occurs. Well-trained technologists and microbiologists, and the introduction of new technologies, will facilitate the development of a wide variety of molecular tests for other infectious diseases at public health laboratories geographically distant from Toronto, thus enhancing overall laboratory testing capacity in the province of Ontario.

  11. Impact of gene patents on diagnostic testing: a new patent landscaping method applied to spinocerebellar ataxia

    PubMed Central

    Berthels, Nele; Matthijs, Gert; Van Overwalle, Geertrui

    2011-01-01

    Recent reports in Europe and the United States raise concern about the potential negative impact of gene patents on the freedom to operate of diagnosticians and on the access of patients to genetic diagnostic services. Patents, historically seen as legal instruments to trigger innovation, could cause undesired side effects in the public health domain. Clear empirical evidence on the alleged hindering effect of gene patents is still scarce. We therefore developed a patent categorization method to determine which gene patents could indeed be problematic. The method is applied to patents relevant for genetic testing of spinocerebellar ataxia (SCA). The SCA test is probably the most widely used DNA test in (adult) neurology, as well as one of the most challenging due to the heterogeneity of the disease. Typically tested as a gene panel covering the five common SCA subtypes, we show that the patenting of SCA genes and testing methods and the associated licensing conditions could have far-reaching consequences on legitimate access to this gene panel. Moreover, with genetic testing being increasingly standardized, simply ignoring patents is unlikely to hold out indefinitely. This paper aims to differentiate among so-called ‘gene patents' by lifting out the truly problematic ones. In doing so, awareness is raised among all stakeholders in the genetic diagnostics field who are not necessarily familiar with the ins and outs of patenting and licensing. PMID:21811306

  12. Evaluation of Altona Diagnostics RealStar Zika Virus RT-PCR Test Kit for Zika virus PCR testing.

    PubMed

    L'Huillier, Arnaud G; Lombos, Ernesto; Tang, Elaine; Perusini, Stephen; Eshaghi, Alireza; Nagra, Sandeep; Frantz, Christine; Olsha, Romy; Kristjanson, Erik; Dimitrova, Kristina; Safronetz, David; Drebot, Mike; Gubbay, Jonathan B

    2017-03-15

    Background: With the emerging ZIKA virus (ZIKV) epidemic, accessible real-time reverse-transcription PCR (rRT-PCR) assays are needed to streamline testing. The commercial Altona Diagnostics RealStar ZIKV rRT-PCR Test Kit has been approved for Emergency Use Authorization by the FDA. Our aim was to verify Altona-PCR, by comparing it to the CDC-designed dual target ZIKV virus rRT-PCR reference assay (Reference-PCR), and describe demographics of patients tested for ZIKV by rRT-PCR in Ontario, Canada.Methods: A large set of clinical specimens were tested for ZIKV by Altona-PCR and Reference-PCR. Positive or equivocal specimens underwent PCR and Sanger sequencing targeting ZIKV NS5 gene.Results: 671 serum specimens were tested by Reference-PCR: 58 (8.6%) were positive, 193 (28.8%) equivocal and 420 (62.6%) negative. Ninety percent of Reference-PCR positive patients were tested in the first 5 days after symptom onset. Altona-PCR was performed on 284/671 tested specimens by Reference-PCR. Altona-PCR was positive in 53/58 (91%) Reference-PCR positive and 16/193 (8%) Reference-PCR equivocal specimens; ZIKV NS5 PCR was positive in all 68 Altona-PCR positive specimens, and negative in all 181 Altona-PCR negative specimens that underwent NS5 PCR.Conclusion: Most ZIKV PCR positive cases are detected in the first five days of illness. Altona-PCR has very good sensitivity (91%) and specificity (97%) compared to Reference-PCR. Altona-PCR can be used for ZIKV diagnostic testing, with less extensive verification requirements compared to a laboratory developed test.

  13. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation

    PubMed Central

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2–90.8% and 83.3–86.9% and a specificity of 97.7–98.8% and 95.1–97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values. PMID:26904678

  14. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation.

    PubMed

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2-90.8% and 83.3-86.9% and a specificity of 97.7-98.8% and 95.1-97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values.

  15. Cerebrospinal Fluid IL-10 and IL-10/IL-6 as Accurate Diagnostic Biomarkers for Primary Central Nervous System Large B-cell Lymphoma

    PubMed Central

    Song, Yang; Zhang, Wei; Zhang, Li; Wu, Wei; Zhang, Yan; Han, Xiao; Yang, Chen; Zhang, Lu; Zhou, Daobin

    2016-01-01

    Early diagnosis of primary central nervous system lymphoma (PCNSL) represents a challenge, and cerebrospinal fluid (CSF) cytokines may be diagnostic biomarkers for PCNSL. We used an electrochemiluminescence immunoassay to measure interleukin (IL)-10, IL-6, IL-8 and tumor necrosis factor α (TNF-α) in the CSF of 22 B cell PCNSL patients and 80 patients with other CNS diseases. CSF IL-10 was significantly higher in PCNSL patients than in the control group (median 74.7 pg/ml vs < 5.0 pg/ml, P < 0.000). Using a CSF IL-10 cutoff value of 8.2 pg/ml, the diagnostic sensitivity and specificity were 95.5% and 96.1%, respectively (AUC, 0.957; 95% CI, 0.901–1.000). For a CSF IL-10/IL-6 cutoff value of 0.72, the sensitivity was 95.5%, and the specificity was 100.0% (AUC, 0.976; 95% CI, 0.929–1.000). An increased CSF IL-10 level at diagnosis and post-treatment was associated with poor Progression free survival (PFS) for patients with PCNSL (P = 0.0181 and P = 0.0002, respectively). A low diagnostic value for PCNSL was found with CSF IL-8 or TNF-α. In conclusion, increased CSF IL-10 was a reliable diagnostic biomarker for large B cell PCNSL, and an IL-10/IL-6 ratio facilitates differentiation from other conditions, especially a CNS infection. PMID:27924864

  16. Center for Disease Control Diagnostic Immunology Proficiency Testing Program results for 1978.

    PubMed Central

    Taylor, R N; Fulford, K M; Przybyszewski, V A; Pope, V

    1979-01-01

    Data from about 1,000 laboratories participating in the Diagnostic Immunology portion of the 1978 Center for Disease Control Proficiency Testing Program provided information dealing with laboratory performance and trends in testing protocols. Ninety specimens were distributed in scheduled quarterly and semiannual shipments, and five additional specimens were provided in a special survey. The specimens offered both qualitative and quantitative challenges for a wide variety of analytes which included syphilis serology, rheumatoid factor, bacterial agglutinins, hepatitis B surface antigen, immunoglobulins and other serum proteins, infectious mononucleosis, rubella, toxoplasma, antinuclear antibodies, and streptococcal exoenzymes. This paper summarizes the results of the 1978 program. PMID:230201

  17. HbA1c as a Diagnostic Test for Diabetes Mellitus – Reviewing the Evidence

    PubMed Central

    Florkowski, Chris

    2013-01-01

    The evidence base in support of HbA1c as a diagnostic test for diabetes mellitus is focused on predicting a clinical outcome, considered to be the pinnacle of the Stockholm Hierarchy applied to reference intervals and clinical decision limits. In the case of diabetes, the major outcome of interest is the long term microvascular complications for which a large body of data has been accumulated, leading to the endorsement of HbA1c for diagnosis in many countries worldwide, with some variations in cut-offs and testing strategies. PMID:24151343

  18. Semi-parametric estimation of the binormal ROC curve for a continuous diagnostic test.

    PubMed

    Cai, Tianxi; Moskowitz, Chaya S

    2004-10-01

    Not until recently has much attention been given to deriving maximum likelihood methods for estimating the intercept and slope parameters from a binormal ROC curve that assesses the accuracy of a continuous diagnostic test. We propose two new methods for estimating these parameters. The first method uses the profile likelihood and a simple algorithm to produce fully efficient estimates. The second method is based on a pseudo-maximum likelihood that can easily accommodate adjusting for covariates that could affect the accuracy of the continuous test.

  19. Autonomic function testing: an important diagnostic test for patients with syncope.

    PubMed

    Jones, Pearl K; Gibbons, Christopher H

    2015-10-01

    Syncope is a common problem with a large differential diagnosis. The initial history and physical examination often provide initial clues; however, some cases warrant further testing to determine the underlying cause. Autonomic function testing is a safe way to evaluate patients with syncope further, and to assess their parasympathetic and sympathetic nervous systems. Autonomic testing can help to diagnose several conditions, including orthostatic hypotension, delayed orthostatic hypotension, postural tachycardia syndrome and neutrally mediated syncope. Thus, when the cause of syncope is unclear, autonomic testing can help to assess the autonomic nervous system, stratify the risk of future episodes and to guide treatment decisions.

  20. Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health.

    PubMed

    Miller, Eric; Sikes, Hadley D

    Immunochromatographic rapid diagnostic tests (RDTs) have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

  1. Uptake of prenatal diagnostic testing for retinoblastoma compared to other hereditary cancer syndromes in the Netherlands.

    PubMed

    Dommering, Charlotte J; Henneman, Lidewij; van der Hout, Annemarie H; Jonker, Marianne A; Tops, Carli M J; van den Ouweland, Ans M W; van der Luijt, Rob B; Mensenkamp, Arjen R; Hogervorst, Frans B L; Redeker, Egbert J W; de Die-Smulders, Christine E M; Moll, Annette C; Meijers-Heijboer, Hanne

    2017-04-01

    Since the 1980s the genetic cause of many hereditary tumor syndromes has been elucidated. As a consequence, carriers of a deleterious mutation in these genes may opt for prenatal diagnoses (PND). We studied the uptake of prenatal diagnosis for five hereditary cancer syndromes in the Netherlands. Uptake for retinoblastoma (Rb) was compared with uptake for Von Hippel-Lindau disease (VHL), Li-Fraumeni syndrome (LFS), familial adenomatous polyposis (FAP), and hereditary breast ovarian cancer (HBOC). A questionnaire was completed by all nine DNA-diagnostic laboratories assessing the number of independent mutation-positive families identified from the start of diagnostic testing until May 2013, and the number of PNDs performed for these syndromes within these families. Of 187 families with a known Rb-gene mutation, 22 had performed PND (11.8%), this was significantly higher than uptake for FAP (1.6%) and HBOC (<0.2%). For VHL (6.5%) and LFS (4.9%) the difference was not statistically significant. PND for Rb started 3 years after introduction of diagnostic DNA testing and remained stable over the years. For the other cancer syndromes PND started 10-15 years after the introduction and uptake for PND showed an increase after 2009. We conclude that uptake of PND for Rb was significantly higher than for FAP and HBOC, but not different from VHL and LFS. Early onset, high penetrance, lack of preventive surgery and perceived burden of disease may explain these differences.

  2. Meta-analysis of diagnostic test data: a bivariate Bayesian modeling approach.

    PubMed

    Verde, Pablo E

    2010-12-30

    In the last decades, the amount of published results on clinical diagnostic tests has expanded very rapidly. The counterpart to this development has been the formal evaluation and synthesis of diagnostic results. However, published results present substantial heterogeneity and they can be regarded as so far removed from the classical domain of meta-analysis, that they can provide a rather severe test of classical statistical methods. Recently, bivariate random effects meta-analytic methods, which model the pairs of sensitivities and specificities, have been presented from the classical point of view. In this work a bivariate Bayesian modeling approach is presented. This approach substantially extends the scope of classical bivariate methods by allowing the structural distribution of the random effects to depend on multiple sources of variability. Meta-analysis is summarized by the predictive posterior distributions for sensitivity and specificity. This new approach allows, also, to perform substantial model checking, model diagnostic and model selection. Statistical computations are implemented in the public domain statistical software (WinBUGS and R) and illustrated with real data examples.

  3. Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health

    PubMed Central

    Miller, Eric; Sikes, Hadley D.

    2015-01-01

    Immunochromatographic rapid diagnostic tests (RDTs) have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs. PMID:26594252

  4. Heavy ion beams from an Alphatross source for use in calibration and testing of diagnostics

    NASA Astrophysics Data System (ADS)

    Ward, R. J.; Brown, G. M.; Ho, D.; Stockler, B. F. O. F.; Freeman, C. G.; Padalino, S. J.; Regan, S. P.

    2016-10-01

    Ion beams from the 1.7 MV Pelletron Accelerator at SUNY Geneseo have been used to test and calibrate many inertial confinement fusion (ICF) diagnostics and high energy density physics (HEDP) diagnostics used at the Laboratory for Laser Energetics (LLE). The ion source on this accelerator, a radio-frequency (RF) alkali-metal charge exchange source called an Alphatross, is designed to produce beams of hydrogen and helium isotopes. There is interest in accelerating beams of carbon, oxygen, argon, and other heavy ions for use in testing several diagnostics, including the Time Resolved Tandem Faraday Cup (TRTF). The feasibility of generating these heavy ion beams using the Alphatross source will be reported. Small amounts of various gases are mixed into the helium plasma in the ion source bottle. A velocity selector is used to allow the desired ions to pass into the accelerator. As the heavy ions pass through the stripper canal of the accelerator, they emerge in a variety of charge states. The energy of the ion beam at the high-energy end of the accelerator will vary as a function of the charge state, however the maximum energy deliverable to target is limited by the maximum achievable magnetic field produced by the accelerator's steering magnet. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  5. Unmet Diagnostic Needs in Infectious Disease

    PubMed Central

    Blaschke, Anne J.; Hersh, Adam L.; Beekmann, Susan E.; Ince, Dilek; Polgreen, Philip M.; Hanson, Kimberly E.

    2014-01-01

    Accurate diagnosis is critical to providing appropriate care in infectious diseases. New technologies for infectious disease diagnostics are emerging, but gaps remain in test development and availability. The Emerging Infections Network surveyed Infectious Diseases physicians to assess unmet diagnostic needs. Responses reflected the urgent need to identify drug-resistant infections and highlighted the potential for early diagnosis to improve antibiotic stewardship. Information gained from this survey can help inform recommendations for new diagnostic test development in the future. PMID:25456043

  6. Diagnostic Yield of Routine Enteropathogenic Stool Tests in Pediatric Ulcerative Colitis

    PubMed Central

    Ihekweazu, Faith D.; Ajjarapu, Avanthi; Kellermayer, Richard

    2017-01-01

    Goals It can be important to exclude infectious etiologies prior to adjusting immunosuppressive therapy in patients with ulcerative colitis (UC) exacerbation. We sought to determine the diagnostic yield of routine infectious stool studies in pediatric UC patients. Procedures We conducted a retrospective review of 152 pediatric UC patients at Texas Children’s Hospital between January 2003 and December 2009. The patient records were followed through July 2014. The number and type of infectious stool studies performed and the results of those were collected. Results Three hundred fifty-four diagnostic stool tests were conducted for Clostridium difficile; 13.6% were positive. Two hundred twenty stool bacterial cultures were performed, and 1.8% were positive, all growing non-typhoid Salmonella. One of 13 (7.7%) Adenovirus PCR tests was positive. Two of 152 examinations (1.3%) for Ova and Parasites were positive. No stool tests for viral culture, viral particles, Yersinia or Rotavirus were positive. Conclusions Clostridium difficile infection is common in pediatric UC, and routine screening during flares is strongly recommended. Other bacterial and parasitic infections routinely tested for are uncommon, but Salmonella may be a potentially important attribute to disease exacerbations in select patients. In patients without co-morbid conditions, the utility of performing non-specific fecal viral tests is questionable. PMID:26663793

  7. Bayes' theorem and diagnostic tests in neuropsychology: interval estimates for post-test probabilities.

    PubMed

    Crawford, John R; Garthwaite, Paul H; Betkowska, Karolina

    2009-05-01

    Most neuropsychologists are aware that, given the specificity and sensitivity of a test and an estimate of the base rate of a disorder, Bayes' theorem can be used to provide a post-test probability for the presence of the disorder given a positive test result (and a post-test probability for the absence of a disorder given a negative result). However, in the standard application of Bayes' theorem the three quantities (sensitivity, specificity, and the base rate) are all treated as fixed, known quantities. This is very unrealistic as there may be considerable uncertainty over these quantities and therefore even greater uncertainty over the post-test probability. Methods of obtaining interval estimates on the specificity and sensitivity of a test are set out. In addition, drawing and extending upon work by Mossman and Berger (2001), a Monte Carlo method is used to obtain interval estimates for post-test probabilities. All the methods have been implemented in a computer program, which is described and made available (www.abdn.ac.uk/~psy086/dept/BayesPTP.htm). When objective data on the base rate are lacking (or have limited relevance to the case at hand) the program elicits opinion for the pre-test probability.

  8. Performance of commercially available serological diagnostic tests to detect Leishmania infantum infection on experimentally infected dogs.

    PubMed

    Rodríguez-Cortés, Alhelí; Ojeda, Ana; Todolí, Felicitat; Alberola, Jordi

    2013-01-31

    Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of a widespread serious zoonotic disease that affects both humans and dogs. Prevalence and incidence of the canine infection are important parameters to determine the risk and the ways to control this reemergent zoonosis. Unfortunately, there is not a gold standard test for Leishmania infection. Our aim was to assess the operative validity of commercial tests used to detect antibodies to Leishmania in serum samples from experimental infections. Three ELISA tests (LEISCAN(®) Leishmania ELISA Test, INGEZIM(®) LEISHMANIA, and INGEZIM(®) LEISHMANIA VET), three immunochromatographic tests (INGEZIM(®) LEISHMACROM, SNAP(®) Leishmania, and WITNESS(®) Leishmania), and one IFAT were evaluated. LEISCAN(®) Leishmania ELISA test achieved the highest sensitivity and accuracy (both 0.98). Specificity was 1 for all tests except for IFAT. All tests but IFAT obtained a positive predictive value of 1, while the maximum negative predictive value was achieved by LEISCAN(®) Leishmania ELISA Test (0.93). The best positive likelihood ratio was obtained by INGEZIM(®) LEISHMANIA VET (30.26), while the best negative likelihood ratio was obtained by LEISCAN(®) Leishmania ELISA Test (0.02). The highest diagnostic odds ratio was achieved by LEISCAN(®) Leishmania ELISA Test (729.00). The largest area under the ROC curve was obtained by LEISCAN(®) Leishmania ELISA Test (0.981). Quantitative ELISA based tests performmed better than qualitative tests ("Rapid Tests"), and the test best suited to detect Leishmania in infected dogs and to provide clinically useful information was LEISCAN(®) Leishmania ELISA Test. This and other results point also to the need of revising the status of IFAT as a gold standard for the diagnosis of leishmaniasis.

  9. The importance of diagnostic test parameters in the interpretation of clinical test findings: The Prone Hip Extension Test as an example

    PubMed Central

    Bruno, Paul

    2011-01-01

    The use of diagnostic tests is a crucial aspect of clinical practice since they assist clinicians in establishing whether a patient has or does not have a particular condition. In order for any clinical test to be used most appropriately, it is essential that several parameters be established regarding the test and that these are made known to clinicians to inform their clinical decision making. These include the test’s sensitivity, specificity, predictive values, and likelihood ratios. This article reviews their importance as well as provides an illustrative example that highlights how knowledge of the parameters for a given test allows clinicians to better interpret their test findings in practice. PMID:21629460

  10. Observed behaviors of patients with probable Alzheimer's disease who are hospitalized for diagnostic tests.

    PubMed

    Day, N; Musallam, K; Wells, M

    1999-11-01

    This study examines observed behaviors of hospitalized patients with probable Alzheimer's disease (AD) undergoing invasive diagnostic procedures. Data was obtained from nursing documentation in the medical records of 30 patients, 10 in each stage of AD (i.e., mild, moderate, severe). In general, analysis of the data revealed that changes in behavior occurred immediately prior to, during, and following these procedures. Specifically, the moderately impaired patients showed the most significant curve over the 5-day observation period, while patients in the mildly impaired group showed a high peak of behavioral change on the test day. The severely impaired group of patients had a higher sustained level of activity throughout the 5-day period. Routine assessment of the patients' usual behaviors, care-givers' knowledge of the stage of disease, and awareness of the potential impact that diagnostics may have on cognitively impaired patients could help care providers decide what interventions most likely would lead to successful outcomes.

  11. An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test Results

    NASA Technical Reports Server (NTRS)

    Rinehart, Aidan W.; Simon, Donald L.

    2015-01-01

    This paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection and isolation purposes. Diagnostic results from the application of the approach to test data acquired from an aircraft turbofan engine are presented. The approach is found to avoid false alarms when presented nominal fault-free data. Additionally, the approach is found to successfully detect and isolate gas path seeded-faults under steady-state operating scenarios although some fault misclassifications are noted during engine transients. Recommendations for follow-on maturation and evaluation of the technique are also presented.

  12. Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

    SciTech Connect

    McGoldrick, P.R.

    1981-01-01

    The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control room consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed.

  13. Field accuracy of fourth-generation rapid diagnostic tests for acute HIV-1: a systematic review

    PubMed Central

    Lewis, Joseph M.; Macpherson, Peter; Adams, Emily R.; Ochodo, Eleanor; Sands, Anita; Taegtmeyer, Miriam

    2015-01-01

    Introduction: Fourth-generation HIV-1 rapid diagnostic tests (RDTs) detect HIV-1 p24 antigen to screen for acute HIV-1. However, diagnostic accuracy during clinical use may be suboptimal. Methods: Clinical sensitivity and specificity of fourth-generation RDTs for acute HIV-1 were collated from field evaluation studies in adults identified by a systematic literature search. Results: Four studies with 17 381 participants from Australia, Swaziland, the United Kingdom and Malawi were identified. All reported 0% sensitivity of the HIV-1 p24 component for acute HIV-1 diagnosis; 26 acute infections were missed. Specificity ranged from 98.3 to 99.9%. Conclusion: Fourth-generation RDTs are currently unsuitable for the detection of acute HIV-1. PMID:26558545

  14. An Integrated Architecture for Aircraft Engine Performance Monitoring and Fault Diagnostics: Engine Test Results

    NASA Technical Reports Server (NTRS)

    Rinehart, Aidan W.; Simon, Donald L.

    2014-01-01

    This paper presents a model-based architecture for performance trend monitoring and gas path fault diagnostics designed for analyzing streaming transient aircraft engine measurement data. The technique analyzes residuals between sensed engine outputs and model predicted outputs for fault detection and isolation purposes. Diagnostic results from the application of the approach to test data acquired from an aircraft turbofan engine are presented. The approach is found to avoid false alarms when presented nominal fault-free data. Additionally, the approach is found to successfully detect and isolate gas path seeded-faults under steady-state operating scenarios although some fault misclassifications are noted during engine transients. Recommendations for follow-on maturation and evaluation of the technique are also presented.

  15. Does the Reporting Quality of Diagnostic Test Accuracy Studies, as Defined by STARD 2015, Affect Citation?

    PubMed Central

    Choi, Young Jun; Chung, Mi Sun; Koo, Hyun Jung; Park, Ji Eun; Yoon, Hee Mang

    2016-01-01

    Objective To determine the rate with which diagnostic test accuracy studies that are published in a general radiology journal adhere to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015, and to explore the relationship between adherence rate and citation rate while avoiding confounding by journal factors. Materials and Methods All eligible diagnostic test accuracy studies that were published in the Korean Journal of Radiology in 2011–2015 were identified. Five reviewers assessed each article for yes/no compliance with 27 of the 30 STARD 2015 checklist items (items 28, 29, and 30 were excluded). The total STARD score (number of fulfilled STARD items) was calculated. The score of the 15 STARD items that related directly to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 was also calculated. The number of times each article was cited (as indicated by the Web of Science) after publication until March 2016 and the article exposure time (time in months between publication and March 2016) were extracted. Results Sixty-three articles were analyzed. The mean (range) total and QUADAS-2-related STARD scores were 20.0 (14.5–25) and 11.4 (7–15), respectively. The mean citation number was 4 (0–21). Citation number did not associate significantly with either STARD score after accounting for exposure time (total score: correlation coefficient = 0.154, p = 0.232; QUADAS-2-related score: correlation coefficient = 0.143, p = 0.266). Conclusion The degree of adherence to STARD 2015 was moderate for this journal, indicating that there is room for improvement. When adjusted for exposure time, the degree of adherence did not affect the citation rate. PMID:27587959

  16. Toward accurate molecular identification of species in complex environmental samples: testing the performance of sequence filtering and clustering methods

    PubMed Central

    Flynn, Jullien M; Brown, Emily A; Chain, Frédéric J J; MacIsaac, Hugh J; Cristescu, Melania E

    2015-01-01

    Metabarcoding has the potential to become a rapid, sensitive, and effective approach for identifying species in complex environmental samples. Accurate molecular identification of species depends on the ability to generate operational taxonomic units (OTUs) that correspond to biological species. Due to the sometimes enormous estimates of biodiversity using this method, there is a great need to test the efficacy of data analysis methods used to derive OTUs. Here, we evaluate the performance of various methods for clustering length variable 18S amplicons from complex samples into OTUs using a mock community and a natural community of zooplankton species. We compare analytic procedures consisting of a combination of (1) stringent and relaxed data filtering, (2) singleton sequences included and removed, (3) three commonly used clustering algorithms (mothur, UCLUST, and UPARSE), and (4) three methods of treating alignment gaps when calculating sequence divergence. Depending on the combination of methods used, the number of OTUs varied by nearly two orders of magnitude for the mock community (60–5068 OTUs) and three orders of magnitude for the natural community (22–22191 OTUs). The use of relaxed filtering and the inclusion of singletons greatly inflated OTU numbers without increasing the ability to recover species. Our results also suggest that the method used to treat gaps when calculating sequence divergence can have a great impact on the number of OTUs. Our findings are particularly relevant to studies that cover taxonomically diverse species and employ markers such as rRNA genes in which length variation is extensive. PMID:26078860

  17. [Development of Standards for Baseline Quality in Quality Management of Molecular-Diagnostic Testing].

    PubMed

    Miyachi, Hayato

    2015-07-01

    As molecular-diagnostic testing is expanding in clinical use, the demand for its quality assurance is increasing. To this end, efforts towards quality management have been made regionally and globally. An entire testing procedure needs to be properly performed from the preanalytic, analytic, and postanalytic processes. Particularly, the preanalytic process largely affects the measurement and, thus, the result. The Japanese Committee for Clinical Laboratory and Standard developed the standard documents, such as that for the quality management of clinical specimens and best-practice guideline for quality assurance of molecular-genetic testing. These standard documents would provide not only the requirements as the best practice for testing, but also the basis of baseline quality and reliability. They can be used as the basis for assessment of the quality of practice in reimbursement coverage by payers and in certification or accreditation by a third party.

  18. Measuring the quality-of-life effects of diagnostic and screening tests.

    PubMed

    Swan, J Shannon; Miksad, Rebecca A

    2009-08-01

    Health-related quality of life (HRQL) is a central concept for understanding the outcomes of medical care. When used in cost-effectiveness analysis, HRQL is typically measured for conditions persisting over long time frames (years), and quality-adjusted life year (QALY) values are generated. Consequently, years are the basic unit of time for cost-effectiveness analysis results: dollars spent per QALY gained. However, shorter term components of health care may also affect HRQL, and there is increased interest in measuring and accounting for these events. In radiology, the short-term HRQL effects of screening and diagnostic testing may affect a test's cost-effectiveness, even though they may only last for days. The unique challenge in radiology HRQL assessment is to realistically tap into the testing and screening experience while remaining consistent with QALY theory. The authors review HRQL assessment and highlight methods developed to specifically address the short-term effects of radiologic screening and testing.

  19. 9 CFR 130.15 - User fees for veterinary diagnostic isolation and identification tests performed at NVSL...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic isolation and identification tests performed at NVSL (excluding FADDL) or other authorized site. 130.15... AGRICULTURE USER FEES USER FEES § 130.15 User fees for veterinary diagnostic isolation and...

  20. The Relationship between Students' Reading Performance on Diagnostic Assessments and the Third Grade Reading Achievement Test in Ohio

    ERIC Educational Resources Information Center

    Hollinger, Jamie L.

    2009-01-01

    The purpose of this correlational study was twofold: to examine the relationship of students' reading performance on six different diagnostic reading assessments and the third grade Ohio Reading Achievement Test; and to assist educators in choosing the diagnostic assessments that best identify students at risk of failing the third grade Ohio…

  1. Meta-analyses of the sensitivity and specificity of ante-mortem and post-mortem diagnostic tests for bovine tuberculosis in the UK and Ireland.

    PubMed

    Nuñez-Garcia, Javier; Downs, Sara H; Parry, Jessica E; Abernethy, Darrell A; Broughan, Jennifer M; Cameron, Angus R; Cook, Alasdair J; de la Rua-Domenech, Ricardo; Goodchild, Anthony V; Gunn, Jane; More, Simon J; Rhodes, Shelley; Rolfe, Simon; Sharp, Michael; Upton, Paul A; Vordermeier, H Martin; Watson, Eamon; Welsh, Michael; Whelan, Adam O; Woolliams, John A; Clifton-Hadley, Richard S; Greiner, Matthias

    2017-03-06

    Bovine Tuberculosis (bTB) in cattle is a global health problem and eradication of the disease requires accurate estimates of diagnostic test performance to optimize their efficiency. The objective of this study was, through statistical meta-analyses, to obtain estimates of sensitivity (Se) and specificity (Sp), for 14 different ante-mortem and post-mortem diagnostic tests for bTB in cattle. Using data from a systematic review of the scientific literature (published 1934-2009) diagnostic Se and Sp were estimated using Bayesian logistic regression models adjusting for confounding factors. Random effect terms were used to account for unexplained heterogeneity. Parameters in the models were implemented using Markov Chain Monte Carlo (MCMC), and posterior distributions for the diagnostic parameters with adjustment for covariates (confounding factors) were obtained using the inverse logit function. Estimates for Se and/or Sp of the tuberculin skin tests and the IFN-γ blood test were compared with estimates published 2010-2015. Median Se for the single intradermal comparative cervical tuberculin skin (SICCT) test (standard interpretation) was 0.50 and Bayesian credible intervals (CrI) were wide (95% CrI 0.26, 0.78). Median Sp for the SICCT test was 1.00 (95% CrI 0.99, 1.00). Estimates for the IFN-γ blood test Bovine Purified Protein Derivative (PPD)-Avian PPD and Early Secreted Antigen target 6 and Culture Filtrate Protein 10 (ESAT-6/CFP10) ESAT6/CFP10 were 0.67 (95% CrI 0.49, 0.82) and 0.78 (95% CrI 0.60, 0.90) respectively for Se, and 0.98 (95% CrI 0.96, 0.99) and 0.99 (95% CrI 0.99, 1.00) for Sp. The study provides an overview of the accuracy of a range of contemporary diagnostic tests for bTB in cattle. Better understanding of diagnostic test performance is essential for the design of effective control strategies and their evaluation.

  2. Diagnostic performance of serological tests for swine brucellosis in the presence of false positive serological reactions.

    PubMed

    Dieste-Pérez, L; Blasco, J M; de Miguel, M J; Moriyón, I; Muñoz, P M

    2015-04-01

    Swine brucellosis caused by Brucella suis biovar 2 is an emerging disease in Europe. Currently used diagnostic tests for swine brucellosis detect antibodies to the O-polysaccharide (O-PS) of Brucella smooth lipopolysaccharide (S-LPS) but their specificity is compromised by false-positive serological reactions (FPSRs) when bacteria carrying cross-reacting O-PS infect pigs. FPSRs occur throughout Europe, and the only tool available for a specific B. suis diagnosis is the intradermal test with Brucella protein extracts free of O-PS or S-LPS. Using sera of 162 sows naturally infected by B. suis biovar 2, 406 brucellosis-free sows, and 218 pigs of brucellosis-free farms affected by FPSR, we assessed the diagnostic performance of an indirect ELISA with rough LPS (thus devoid of O-PS) and of gel immunodiffusion, counterimmunoelectrophoresis, latex agglutination and indirect ELISA with O-PS free proteins in comparison with several S-LPS tests (Rose Bengal, complement fixation, gel immunodiffusion and indirect ELISA). When adjusted to 100% specificity, the sensitivity of the rough LPS ELISA was very low (30%), and adoption of other cut-offs resulted in poor specificity/sensitivity ratios. Although their specificity was 100%, the sensitivity of protein tests (ELISA, latex agglutination, counterimmunoelectrophoresis, and gel immunodiffusion) was only moderate (45, 58, 61 and 63%, respectively). Among S-LPS tests, gel immunodiffusion was the only test showing acceptable sensitivity/specificity (68 and 100%, respectively). Despite these shortcomings, and when the purpose is to screen out FPSR at herd level, gel immunodiffusion tests may offer a technically simple and practical alternative to intradermal testing.

  3. Diagnostic and screening power of neuropsychological testing in detecting mild cognitive impairment in Parkinson's disease.

    PubMed

    Biundo, Roberta; Weis, Luca; Pilleri, Manuela; Facchini, Silvia; Formento-Dojot, Patrizia; Vallelunga, Annamaria; Antonini, Angelo

    2013-04-01

    Prevalence of mild cognitive impairment (MCI) in Parkinson's disease (PD) is variable likely due to methodological differences in classification criteria and lack of consensus about neuropsychological tests used for cognitive profiling. The main objective of our study was to identify the most suitable neuropsychological tests and determine their screening and diagnostic cutoff scores for PD-MCI. A series of 104 consecutive PD patients performed an extensive neuropsychological evaluation. Individual test values were converted into Z-scores using relative published normative data. According to published criteria, PD patients were categorized as PD-CNT (PD without cognitive impairment), PD-MCI (patients performing -1.5 SDs below the mean score in at least one cognitive domain), and PDD. We used receiver operating characteristic (ROC) curves and K-means clustering analyses to calculate the best discriminating power of each neuropsychological tests in detecting PD-MCI. PD patients were categorized as follows: 55 PD-CNT (53 %), 34 PD-MCI (33 %), and 15 PDD (14 %). PD-MCI had lower education, longer disease duration and greater frequency of hallucinations than PD-CNT. We found that only the Trail Making test, Rey-Osterrieth Complex Figure Test (ROCF) copy, Frontal Assessment Battery (FAB), Digit Span Backward, and Rey's word auditory verbal learning test (RVLT) immediate recall reached significant screening and diagnostic validity in predicting PD-MCI (AUC 0.705-0.795) with cutoff scores calculated by ROC analyses lying within normal range for normative data. Specific neuropsychological tests covering verbal memory, attention/set-shifting, and visual-spatial deficits are the best predictors of MCI in PD if valid cutoff scores are used. These results have consequences for cognitive diagnosis and potentially in establishing the rate of PD cognitive decline.

  4. Update on diagnostic value of breath test in gastrointestinal and liver diseases

    PubMed Central

    Siddiqui, Imran; Ahmed, Sibtain; Abid, Shahab

    2016-01-01

    In the field of gastroenterology, breath tests (BTs) are used intermittently as diagnostic tools that allow indirect, non-invasive and relatively less cumbersome evaluation of several disorders by simply quantifying the appearance in exhaled breath of a metabolite of a specific substrate administered. The aim of this review is to have an insight into the principles, methods of analysis and performance parameters of various hydrogen, methane and carbon BTs which are available for diagnosing gastrointestinal disorders such as Helicobacter pylori infection, small intestinal bacterial overgrowth, and carbohydrate malabsorption. Evaluation of gastric emptying is routinely performed by scintigraphy which is however, difficult to perform and not suitable for children and pregnant women, this review has abridged the 13C-octanoic acid test in comparison to scintigraphy and has emphasized on its working protocol and challenges. A new development such as electronic nose test is also highlighted. Moreover we have also explored the limitations and constraints restraining the wide use of these BT. We conclude that breath testing has an enormous potential to be used as a diagnostic modality. In addition it offers distinct advantages over the traditional invasive methods commonly employed. PMID:27574563

  5. Highlights from the 2016 HIV diagnostics conference: The new landscape of HIV testing in laboratories, public health programs and clinical practice.

    PubMed

    Wesolowski, Laura G; Parker, Monica M; Delaney, Kevin P; Owen, S Michele

    2017-02-07

    The 2016 HIV Diagnostics Conference, held in Atlanta, Georgia, was attended by public health officials, laboratorians, HIV testing program managers, surveillance coordinators and industry representatives. The conference addressed test performance data, the implementation of new testing algorithms, quality assurance, and the application of new tests in a variety of settings. With regard to the recommended Centers for Disease Control and Prevention/Association of Public Health Laboratories HIV laboratory testing algorithm, the conference featured performance data, implementation challenges such as a lack of test options for the second and third steps, as well as data needs for new tests that may be used as part of the algorithm. There are delays when nucleic acid testing is needed with the algorithm. Novel tests such as point of care nucleic acid tests are needed on the U.S. market to readily identify acute infection. Multiplex tests are being developed which allow for the simultaneous detection of multiple pathogens. CDC staff highlighted new guidance for testing in non-clinical settings. Innovative approaches to linking testing and care in some settings have led to identification of early infections, improved receipt of test results and expedited initiation of therapy. Work continues to optimize testing so that infections are accurately identified as early as possible and time to treatment is minimized to improve health outcomes and prevent transmission.

  6. Exploring Ways to Provide Diagnostic Feedback with an ESL Placement Test: Cognitive Diagnostic Assessment of L2 Reading Ability

    ERIC Educational Resources Information Center

    Kim, Ah-Young

    2015-01-01

    Previous research in cognitive diagnostic assessment (CDA) of L2 reading ability has been frequently conducted using large-scale English proficiency exams (e.g., TOEFL, MELAB). Using CDA, it is possible to analyze individual learners' strengths and weaknesses in multiple attributes (i.e., knowledge, skill, strategy) measured at the item level.…

  7. Accurate Time-Dependent Traveling-Wave Tube Model Developed for Computational Bit-Error-Rate Testing

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.

    2001-01-01

    The phenomenal growth of the satellite communications industry has created a large demand for traveling-wave tubes (TWT's) operating with unprecedented specifications requiring the design and production of many novel devices in record time. To achieve this, the TWT industry heavily relies on computational modeling. However, the TWT industry's computational modeling capabilities need to be improved because there are often discrepancies between measured TWT data and that predicted by conventional two-dimensional helical TWT interaction codes. This limits the analysis and design of novel devices or TWT's with parameters differing from what is conventionally manufactured. In addition, the inaccuracy of current computational tools limits achievable TWT performance because optimized designs require highly accurate models. To address these concerns, a fully three-dimensional, time-dependent, helical TWT interaction model was developed using the electromagnetic particle-in-cell code MAFIA (Solution of MAxwell's equations by the Finite-Integration-Algorithm). The model includes a short section of helical slow-wave circuit with excitation fed by radiofrequency input/output couplers, and an electron beam contained by periodic permanent magnet focusing. A cutaway view of several turns of the three-dimensional helical slow-wave circuit with input/output couplers is shown. This has been shown to be more accurate than conventionally used two-dimensional models. The growth of the communications industry has also imposed a demand for increased data rates for the transmission of large volumes of data. To achieve increased data rates, complex modulation and multiple access techniques are employed requiring minimum distortion of the signal as it is passed through the TWT. Thus, intersymbol interference (ISI) becomes a major consideration, as well as suspected causes such as reflections within the TWT. To experimentally investigate effects of the physical TWT on ISI would be

  8. A Bayesian framework to assess the potential for controlling classical scrapie in sheep flocks using a live diagnostic test.

    PubMed

    Gryspeirt, Aiko; Gubbins, Simon

    2013-09-01

    Current strategies to control classical scrapie remove animals at risk of scrapie rather than those known to be infected with the scrapie agent. Advances in diagnostic tests, however, suggest that a more targeted approach involving the application of a rapid live test may be feasible in future. Here we consider the use of two diagnostic tests: recto-anal mucosa-associated lymphatic tissue (RAMALT) biopsies; and a blood-based assay. To assess their impact we developed a stochastic age- and prion protein (PrP) genotype-structured model for the dynamics of scrapie within a sheep flock. Parameters were estimated in a Bayesian framework to facilitate integration of a number of disparate datasets and to allow parameter uncertainty to be incorporated in model predictions. In small flocks a control strategy based on removal of clinical cases was sufficient to control disease and more stringent measures (including the use of a live diagnostic test) did not significantly reduce outbreak size or duration. In medium or large flocks strategies in which a large proportion of animals are tested with either live diagnostic test significantly reduced outbreak size, but not always duration, compared with removal of clinical cases. However, the current Compulsory Scrapie Flocks Scheme (CSFS) significantly reduced outbreak size and duration compared with both removal of clinical cases and all strategies using a live diagnostic test. Accordingly, under the assumptions made in the present study there is little benefit from implementing a control strategy which makes use of a live diagnostic test.

  9. Effects of Concept Map Extraction and a Test-Based Diagnostic Environment on Learning Achievement and Learners' Perceptions

    ERIC Educational Resources Information Center

    Lin, Yu-Shih; Chang, Yi-Chun; Liew, Keng-Hou; Chu, Chih-Ping

    2016-01-01

    Computerised testing and diagnostics are critical challenges within an e-learning environment, where the learners can assess their learning performance through tests. However, a test result based on only a single score is insufficient information to provide a full picture of learning performance. In addition, because test results implicitly…

  10. Effect of Two-Tier Diagnostic Tests on Promoting Learners' Conceptual Understanding of Variables in Conducting Scientific Experiments

    ERIC Educational Resources Information Center

    Çil, Emine

    2015-01-01

    Taking a test generally improves the retention of the material tested. This is a phenomenon commonly referred to as testing effect. The present research investigated whether two-tier diagnostic tests promoted student teachers' conceptual understanding of variables in conducting scientific experiments, which is a scientific process skill. In this…

  11. Application of receiver-operator analysis to diagnostic tests of iron deficiency in man.

    PubMed

    Kim, I; Pollitt, E; Leibel, R L; Viteri, F E; Alvarez, E

    1984-09-01

    The objective of the present report is to demonstrate the use of receiver-operator characteristics (ROC) analysis in the selection of diagnostic tests for iron deficiency in a specific population. Conventional ROC curves were prepared with true positive fraction (TPF) and false positive fraction (FPF) determined by the application of different cut-off points for four indicators of iron status. ROC plots were then transformed into normal deviate scales. The advantages of Gaussian transformation of TPF and FPF when underlying decision functions are normally distributed are: the ROC curve is a straight line; and the separation between the two distributions and shape of these distributions can be simply quantitated as intercepts and slopes. In the present study, pretreatment hemoglobin concentration was the most robust diagnostic indicator of iron deficiency as operationally defined by a response of hemoglobin to iron treatment. Free erythrocyte protoporphyrin was a more sensitive and specific predictor than either serum ferritin or transferin saturation when a stringent operational definition of iron deficiency was used. These findings illustrate the utility of ROC analysis in discriminating between diagnostic indicators having different degrees of accuracy.

  12. Personality Assessment in the Diagnostic Manuals: On Mindfulness, Multiple Methods, and Test Score Discontinuities

    PubMed Central

    Bornstein, Robert F.

    2015-01-01

    Recent controversies have illuminated the strengths and limitations of different frameworks for conceptualizing personality pathology (e.g., trait perspectives, categorical models), and stimulated debate regarding how best to diagnose personality disorders (PDs) in DSM-5, and in other diagnostic systems (i.e., the International Classification of Diseases, the Psychodynamic Diagnostic Manual). In this article I argue that regardless of how PDs are conceptualized and which diagnostic system is employed, multi-method assessment must play a central role in PD diagnosis. By complementing self-reports with evidence from other domains (e.g., performance-based tests), a broader range of psychological processes are engaged in the patient, and the impact of self-perception and self-presentation biases may be better understood. By providing the assessor with evidence drawn from multiple modalities, some of which provide converging patterns and some of which yield divergent results, the assessor is compelled to engage this evidence more deeply. The mindful processing that ensues can help minimize the deleterious impact of naturally occurring information processing bias and distortion on the part of the clinician (e.g., heuristics, attribution errors), bringing greater clarity to the synthesis and integration of assessment data. PMID:25856565

  13. Application of diagnostic tests for mycoplasmal infections of desert and gopher tortoises with management recommendations

    USGS Publications Warehouse

    Brown, D.R.; Schumacher, Isabella M.; Mclaughlin, Grace S.; Wendland, L.D.; Brown, Mary E.; Klein, P.A.; Jacobson, E.R.

    2002-01-01

    Mycoplasmosis is a transmissible upper respiratory tract disease that has affected plans for management and conservation of wild desert and gopher tortoises in the United States. Although impact of mycoplasmosis on populations of desert and gopher tortoises is unknown, increased prevalence of seropositive animals as well as field observations of clinically ill tortoises have occurred in association with declining populations. In order to help in the identification of potentially infected animals, three tests have been developed to diagnose mycoplasmal infections of tortoises: 1) direct mycoplasmal culture; 2) detection of mycolplasmal chromosomal DNA by polymerase chain reaction (PCR); and 3) detection of anti-Mycoplasma antibodies in tortoise plasma by enzyme-linked immunosorbent assay (ELISA). Each test provides different, complementary information that collectively can be used to define tortoise mycoplasmal infection status. The types of samples required, the predictive value, interpretation, and cost vary among tests. These assays have been used for epidemiological surveys and in decision making for relocation, repatriation, or captive management of tortoises to minimize the risk of outbreaks of mycoplasmal respiratory disease and spread of the causative agent of this disease. Certain features of mycoplasmal infections of tortoises and other animals create a diagnostic dilemma. Multiple Mycoplasma species can cause respiratory disease with identical clinical presentations. Further, individual strains of a given species may vary with respect to their virulence potential, and some species may be commensals rather than pathogens. Current diagnostic tests may not differentiate among mycoplasmal species or strains or permit determination of pathogenicity of individual isolates. Thus, the information provided by testing is not a simple 'positive' vs. 'negative' issue. While these tests provide much needed information on the exposure of tortoise populations to

  14. Comparison of the Diagnostic Accuracy of Three Rapid Tests for the Serodiagnosis of Hepatic Cystic Echinococcosis in Humans

    PubMed Central

    Tamarozzi, Francesca; Covini, Ilaria; Mariconti, Mara; Narra, Roberta; Tinelli, Carmine; De Silvestri, Annalisa; Manzoni, Federica; Casulli, Adriano; Ito, Akira; Neumayr, Andreas; Brunetti, Enrico

    2016-01-01

    Background The diagnosis of cystic echinococcosis (CE) is based primarily on imaging, in particular with ultrasound for abdominal CE, complemented by serology when imaging results are unclear. In rural endemic areas, where expertise in ultrasound may be scant and conventional serology techniques are unavailable due to lack of laboratory equipment, Rapid Diagnostic Tests (RDTs) are appealing. Methodology/Principal Findings We evaluated the diagnostic accuracy of 3 commercial RDTs for the diagnosis of hepatic CE. Sera from 59 patients with single hepatic CE cysts in well-defined ultrasound stages (gold standard) and 25 patients with non-parasitic cysts were analyzed by RDTs VIRapid HYDATIDOSIS (Vircell, Spain), Echinococcus DIGFA (Unibiotest, China), ADAMU-CE (ICST, Japan), and by RIDASCREEN Echinococcus IgG ELISA (R-Biopharm, Germany). Sensitivity, specificity and ROC curves were compared with McNemar and t-test. For VIRapid and DIGFA, correlation between semiquantitative results and ELISA OD values were evaluated by Spearman’s coefficient. Reproducibility was assessed on 16 randomly selected sera with Cohen’s Kappa coefficient. Sensitivity and Specificity of VIRapid (74%, 96%) and ADAMU-CE (57%, 100%) did not differ from ELISA (69%, 96%) while DIGFA (72%, 72%) did (p = 0.045). ADAMU-CE was significantly less sensitive in the diagnosis of active cysts (p = 0.019) while DIGFA was significantly less specific (p = 0.014) compared to ELISA. All tests were poorly sensitive in diagnosing inactive cysts (33.3% ELISA and ADAMU-CE, 42.8% DIGFA, 47.6% VIRapid). The reproducibility of all RDTs was good-very good. Band intensity of VIRapid and DIGFA correlated with ELISA OD values (r = 0.76 and r = 0.79 respectively, p<0.001). Conclusions/Significance RDTs may be useful in resource-poor settings to complement ultrasound diagnosis of CE in uncertain cases. VIRapid test appears to perform best among the examined kits, but all tests are poorly sensitive in the presence of

  15. Cholera Rapid Test with Enrichment Step Has Diagnostic Performance Equivalent to Culture

    PubMed Central

    Ontweka, Lameck N.; Deng, Lul O.; Rauzier, Jean; Debes, Amanda K.; Tadesse, Fisseha; Parker, Lucy A.; Wamala, Joseph F.; Bior, Bior K.; Lasuba, Michael; But, Abiem Bona; Grandesso, Francesco; Jamet, Christine; Cohuet, Sandra; Ciglenecki, Iza; Serafini, Micaela; Sack, David A.; Quilici, Marie-Laure; Azman, Andrew S.; Luquero, Francisco J.

    2016-01-01

    Cholera rapid diagnostic tests (RDT) could play a central role in outbreak detection and surveillance in low-resource settings, but their modest performance has hindered their broad adoption. The addition of an enrichment step may improve test specificity. We describe the results of a prospective diagnostic evaluation of the Crystal VC RDT (Span Diagnostics, India) with enrichment step and of culture, each compared to polymerase chain reaction (PCR), during a cholera outbreak in South Sudan. RDTs were performed on alkaline peptone water inoculated with stool and incubated for 4–6 hours at ambient temperature. Cholera culture was performed from wet filter paper inoculated with stool. Molecular detection of Vibrio cholerae O1 by PCR was done from dry Whatman 903 filter papers inoculated with stool, and from wet filter paper supernatant. In August and September 2015, 101 consecutive suspected cholera cases were enrolled, of which 36 were confirmed by PCR. The enriched RDT had 86.1% (95% CI: 70.5–95.3) sensitivity and 100% (95% CI: 94.4–100) specificity compared to PCR as the reference standard. The sensitivity of culture versus PCR was 83.3% (95% CI: 67.2–93.6) for culture performed on site and 72.2% (95% CI: 54.8–85.8) at the international reference laboratory, where samples were tested after an average delay of two months after sample collection, and specificity was 98.5% (95% CI: 91.7–100) and 100% (95% CI: 94.5–100), respectively. The RDT with enrichment showed performance comparable to that of culture and could be a sustainable alternative to culture confirmation where laboratory capacity is limited. PMID:27992488

  16. Cholera Rapid Test with Enrichment Step Has Diagnostic Performance Equivalent to Culture.

    PubMed

    Ontweka, Lameck N; Deng, Lul O; Rauzier, Jean; Debes, Amanda K; Tadesse, Fisseha; Parker, Lucy A; Wamala, Joseph F; Bior, Bior K; Lasuba, Michael; But, Abiem Bona; Grandesso, Francesco; Jamet, Christine; Cohuet, Sandra; Ciglenecki, Iza; Serafini, Micaela; Sack, David A; Quilici, Marie-Laure; Azman, Andrew S; Luquero, Francisco J; Page, Anne-Laure

    2016-01-01

    Cholera rapid diagnostic tests (RDT) could play a central role in outbreak detection and surveillance in low-resource settings, but their modest performance has hindered their broad adoption. The addition of an enrichment step may improve test specificity. We describe the results of a prospective diagnostic evaluation of the Crystal VC RDT (Span Diagnostics, India) with enrichment step and of culture, each compared to polymerase chain reaction (PCR), during a cholera outbreak in South Sudan. RDTs were performed on alkaline peptone water inoculated with stool and incubated for 4-6 hours at ambient temperature. Cholera culture was performed from wet filter paper inoculated with stool. Molecular detection of Vibrio cholerae O1 by PCR was done from dry Whatman 903 filter papers inoculated with stool, and from wet filter paper supernatant. In August and September 2015, 101 consecutive suspected cholera cases were enrolled, of which 36 were confirmed by PCR. The enriched RDT had 86.1% (95% CI: 70.5-95.3) sensitivity and 100% (95% CI: 94.4-100) specificity compared to PCR as the reference standard. The sensitivity of culture versus PCR was 83.3% (95% CI: 67.2-93.6) for culture performed on site and 72.2% (95% CI: 54.8-85.8) at the international reference laboratory, where samples were tested after an average delay of two months after sample collection, and specificity was 98.5% (95% CI: 91.7-100) and 100% (95% CI: 94.5-100), respectively. The RDT with enrichment showed performance comparable to that of culture and could be a sustainable alternative to culture confirmation where laboratory capacity is limited.

  17. Is there a pathological alpha angle for hip impingement? A diagnostic test study

    PubMed Central

    Barrientos, Cristián; Barahona, Maximiliano; Diaz, Jorge; Brañes, Julian; Chaparro, Felipe; Hinzpeter, Jaime

    2016-01-01

    The normal value of alpha angle is controversial. The aim of this study was to compare the alpha angle in asymptomatic volunteers versus patients who had undergone surgery for symptomatic cam-type femoroacetabular impingement (FAI) and determine a diagnostic cut-off value for symptomatic cam impingement. This is a diagnostic test study. Cases were defined as those patients who had undergone surgery for symptomatic cam or mixed type FAI. Controls were defined as asymptomatic volunteers, with no history of hip pain who had undergone a computed tomography (CT) scan of the abdomen and pelvis for a non-joint or bone-related reason. In both groups, the alpha angle was measured in an oblique axial CT reconstruction of the femoral neck. A logistic regression model was first estimated and a receiver operating characteristics (ROC) curve was then calculated. The diagnostic cut-off value selected was the one that maximizes sensitivity and specificity. Data were analysed from 38 consecutive cases of cam or mixed FAI and 101 controls. The average alpha angle was 67°(±12°) among cases and 48°°(±5°) among controls. An odds ratio of 1.28 [1.18–1.39] was obtained. A ROC curve of 0.96 [0.93–0.99] was calculated, and using an alpha angle of 57° as the diagnostic cut-off value, provided a sensitivity of 92% and a specificity of 95%. If a patient complains of hip pain and an alpha angle of 57° is found in CT, strongly suggest that cam impingement is causing the pain. PMID:27583162

  18. TESTING DIAGNOSTICS OF NUCLEAR ACTIVITY AND STAR FORMATION IN GALAXIES AT z > 1

    SciTech Connect

    Trump, Jonathan R.; Barro, Guillermo; Koo, David C.; Faber, S. M.; Kocevski, Dale D.; Yan, Renbin; Juneau, Stephanie; McLean, Ian S.; Perez-Gonzalez, Pablo G.; Villar, Victor

    2013-01-20

    We present some of the first science data with the new Keck/MOSFIRE instrument to test the effectiveness of different AGN/SF diagnostics at z {approx} 1.5. MOSFIRE spectra were obtained in three H-band multi-slit masks in the GOODS-S field, resulting in 2 hr exposures of 36 emission-line galaxies. We compare X-ray data with the traditional emission-line ratio diagnostics and the alternative mass-excitation and color-excitation diagrams, combining new MOSFIRE infrared data with previous HST/WFC3 infrared spectra (from the 3D-HST survey) and multiwavelength photometry. We demonstrate that a high [O III]/H{beta} ratio is insufficient as an active galactic nucleus (AGN) indicator at z > 1. For the four X-ray-detected galaxies, the classic diagnostics ([O III]/H{beta} versus [N II]/H{alpha} and [S II]/H{alpha}) remain consistent with X-ray AGN/SF classification. The X-ray data also suggest that 'composite' galaxies (with intermediate AGN/SF classification) host bona fide AGNs. Nearly {approx}2/3 of the z {approx} 1.5 emission-line galaxies have nuclear activity detected by either X-rays or the classic diagnostics. Compared to the X-ray and line ratio classifications, the mass-excitation method remains effective at z > 1, but we show that the color-excitation method requires a new calibration to successfully identify AGNs at these redshifts.

  19. Testing Diagnostics of Nuclear Activity and Star Formation in Galaxies at z > 1

    NASA Astrophysics Data System (ADS)

    Trump, Jonathan R.; Konidaris, Nicholas P.; Barro, Guillermo; Koo, David C.; Kocevski, Dale D.; Juneau, Stéphanie; Weiner, Benjamin J.; Faber, S. M.; McLean, Ian S.; Yan, Renbin; Pérez-González, Pablo G.; Villar, Victor

    2013-01-01

    We present some of the first science data with the new Keck/MOSFIRE instrument to test the effectiveness of different AGN/SF diagnostics at z ~ 1.5. MOSFIRE spectra were obtained in three H-band multi-slit masks in the GOODS-S field, resulting in 2 hr exposures of 36 emission-line galaxies. We compare X-ray data with the traditional emission-line ratio diagnostics and the alternative mass-excitation and color-excitation diagrams, combining new MOSFIRE infrared data with previous HST/WFC3 infrared spectra (from the 3D-HST survey) and multiwavelength photometry. We demonstrate that a high [O III]/Hβ ratio is insufficient as an active galactic nucleus (AGN) indicator at z > 1. For the four X-ray-detected galaxies, the classic diagnostics ([O III]/Hβ versus [N II]/Hα and [S II]/Hα) remain consistent with X-ray AGN/SF classification. The X-ray data also suggest that "composite" galaxies (with intermediate AGN/SF classification) host bona fide AGNs. Nearly ~2/3 of the z ~ 1.5 emission-line galaxies have nuclear activity detected by either X-rays or the classic diagnostics. Compared to the X-ray and line ratio classifications, the mass-excitation method remains effective at z > 1, but we show that the color-excitation method requires a new calibration to successfully identify AGNs at these redshifts. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. Also based on data obtained at the W. M. Keck Observatory, made possible by the generous financial support of the W. M. Keck Foundation and operated as a scientific partnership among Caltech, the University of California, and NASA.

  20. ViDI: Virtual Diagnostics Interface. Volume 1; The Future of Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Fleming, Gary A. (Technical Monitor); Schwartz, Richard J.

    2004-01-01

    The quality of data acquired in a given test facility ultimately resides within the fidelity and implementation of the instrumentation systems. Over the last decade, the emergence of robust optical techniques has vastly expanded the envelope of measurement possibilities. At the same time the capabilities for data processing, data archiving and data visualization required to extract the highest level of knowledge from these global, on and off body measurement techniques have equally expanded. Yet today, while the instrumentation has matured to the production stage, an optimized solution for gaining knowledge from the gigabytes of data acquired per test (or even per test point) is lacking. A technological void has to be filled in order to possess a mechanism for near-real time knowledge extraction during wind tunnel experiments. Under these auspices, the Virtual Diagnostics Interface, or ViDI, was developed.

  1. Temperature of a Dengue Rapid Diagnostic Test under Tropical Climatic Conditions: A Follow Up Study

    PubMed Central

    Sengvilaipaseuth, Onanong; Phommasone, Koukeo; de Lamballerie, Xavier; Vongsouvath, Manivanh; Phonemixay, Ooyanong; Blacksell, Stuart D.; Mayxay, Mayfong; Keomany, Sommay; Souvannasing, Phoutthalavanh; Newton, Paul N.

    2017-01-01

    The Dengue Duo Rapid Diagnostic Test (SD Dengue RDT) has good specificity and sensitivity for dengue diagnosis in rural tropical areas. In a previous study, using four control sera, we demonstrated that that the diagnostic accuracy of these RDTs remains stable after long-term storage at high temperatures. We extended this study by testing sera from 119 febrile patients collected between July-November 2012 at Salavan Provincial Hospital (southern Laos) with RDTs stored for 6 months at 4°C, 35° and in a hut (miniature traditional house) at Lao ambient temperatures. The dengue NS1 antigen results from RDTs stored at 35°C and in the hut demonstrated 100% agreement with those stored at 4°C. However, lower positive percent agreements, with broad 95%CI, were observed for the tests: IgM, 60% (14.7–94.7) and 40% (5.3–85.3) for RDTs store at 35°C and in the hut, compared to those stored at 4°C, respectively. This study strenghtens the evidence of the robustness of the NS1 antigen detection RDT for the diagnosis of dengue after storage at tropical temperatures. PMID:28129346

  2. HER2 diagnostics in gastric cancer-guideline validation and development of standardized immunohistochemical testing.

    PubMed

    Rüschoff, Josef; Dietel, Manfred; Baretton, Gustavo; Arbogast, Susanne; Walch, Axel; Monges, Geneviéve; Chenard, Marie-Pierre; Penault-Llorca, Frédérique; Nagelmeier, Iris; Schlake, Werner; Höfler, H; Kreipe, H H

    2010-09-01

    Trastuzumab-based therapy has been shown to confer overall survival benefit in HER2-positive patients with advanced gastric cancer in a large multicentric trial (ToGA study). Subgroup analysis identified adenocarcinomas of the stomach and gastroesophageal (GE) junction with overexpression of HER2 according to immunohistochemistry (IHC) as potential responders. Due to recent approval of trastuzumab for HER2 positive metastatic gastric and GE-junction cancer in Europe (EMEA) HER2 diagnostics is now mandatory with IHC being the primary test followed by fluorescence in situ hybridization (FISH) in IHC2+ cases. However, in order to not miss patients potentially responding to targeted therapy determination of a HER2-positive status for gastric cancer required modification of scoring as had been proposed in a pre-ToGA study. To validate this new HER2 status testing procedure in terms of inter-laboratory and inter-observer consensus for IHC scoring a series of 547 gastric cancer tissue samples on a tissue microarray (TMA) was used. In the first step, 30 representative cores were used to identify specific IHC HER2 scoring issues among eight French and German laboratories, while in the second step the full set of 547 cores was used to determine IHC HER2 intensity and area score concordance between six German pathologists. Specific issues relating to discordance were identified and recommendations formulated which proved to be effective to reliably determine HER2 status in a prospective test series of 447 diagnostic gastric cancer specimens.

  3. Development of a diagnostic test for Johne's disease using a DNA hybridization probe.

    PubMed Central

    Hurley, S S; Splitter, G A; Welch, R A

    1989-01-01

    A DNA probe, M13 mpHAW71, that detects Mycobacterium paratuberculosis in the fecal material of infected animals was developed for use in the diagnosis of Johne's disease. The probe detected as few as 10(5) M. paratuberculosis when hybridized under stringent conditions to total genomic DNA purified from bovine fecal material. When the probe was used diagnostically, it did not differentiate members of the Mycobacterium avium-M. intracellulare-M. paratuberculosis complex. Compared with culturing, the DNA probe identified 34.4% more mycobacterium-containing fecal samples, and testing took only 72 h to complete. Images PMID:2768445

  4. Gamma radiation grafted polymers for immobilization of Brucella antigen in diagnostic test studies

    NASA Astrophysics Data System (ADS)

    Docters, E. H.; Smolko, E. E.; Suarez, C. E.

    The radiation grafting process has a wide field of industrial applications, and in the recent years the immobilization of biocomponents in grafted polymeric materials obtained by means of ionizing radiations is a new and important contribution to biotechnology. In the present work, gamma preirradiation grafting method was employed to produce acrylics hydrogels onto polyethylene (PE), polyvinyl chloride (PVC) and polystyrene (PS). Two monomers were used to graft the previously mentioned polymers: methacrylic acid (MAAc) and acrylamide (AAm), and several working conditions were considered as influencing the degree of grafting. All this grafted polymers were used to study the possibility of a subsequent immobilization of Brucella antigen (BAg) in diagnostic test studies (ELISA).

  5. Accurate ab initio potential energy computations for the H sub 4 system: Tests of some analytic potential energy surfaces

    SciTech Connect

    Boothroyd, A.I. ); Dove, J.E.; Keogh, W.J. ); Martin, P.G. ); Peterson, M.R. )

    1991-09-15

    The interaction potential energy surface (PES) of H{sub 4} is of great importance for quantum chemistry, as a test case for molecule--molecule interactions. It is also required for a detailed understanding of certain astrophysical processes, namely, collisional excitation and dissociation of H{sub 2} in molecular clouds, at densities too low to be accessible experimentally. Accurate {ital ab} {ital initio} energies were computed for 6046 conformations of H{sub 4}, using a multiple reference (single and) double excitation configuration interaction (MRD-CI) program. Both systematic and random'' errors were estimated to have an rms size of 0.6 mhartree, for a total rms error of about 0.9 mhartree (or 0.55 kcal/mol) in the final {ital ab} {ital initio} energy values. It proved possible to include in a self-consistent way {ital ab} {ital initio} energies calculated by Schwenke, bringing the number of H{sub 4} conformations to 6101. {ital Ab} {ital initio} energies were also computed for 404 conformations of H{sub 3}; adding {ital ab} {ital initio} energies calculated by other authors yielded a total of 772 conformations of H{sub 3}. (The H{sub 3} results, and an improved analytic PES for H{sub 3}, are reported elsewhere.) {ital Ab} {ital initio} energies are tabulated in this paper only for a sample of H{sub 4} conformations; a full list of all 6101 conformations of H{sub 4} (and 772 conformations of H{sub 3} ) is available from Physics Auxiliary Publication Service (PAPS), or from the authors.

  6. Small-scale deflagration cylinder test with velocimetry wall-motion diagnostics

    SciTech Connect

    Hooks, Daniel E; Hill, Larry G; Pierce, Timothy H

    2010-01-01

    Predicting the likelihood and effects of outcomes resultant from thermal initiation of explosives remains a significant challenge. For certain explosive formulations, the general outcome can be broadly predicted given knowledge of certain conditions. However, there remain unexplained violent events, and increased statistical understanding of outcomes as a function of many variables, or 'violence categorization,' is needed. Additionally, the development of an equation of state equivalent for deflagration would be very useful in predicting possible detailed event consequences using traditional hydrodynamic detonation moders. For violence categorization, it is desirable that testing be efficient, such that it is possible to statistically define outcomes reliant on the processes of initiation of deflagration, steady state deflagration, and deflagration to detonation transitions. If the test simultaneously acquires information to inform models of violent deflagration events, overall predictive capabilities for event likelihood and consequence might improve remarkably. In this paper we describe an economical scaled deflagration cylinder test. The cyclotetramethylene tetranitramine (HMX) based explosive formu1lation PBX 9501 was tested using different temperature profiles in a thick-walled copper cylindrical confiner. This test is a scaled version of a recently demonstrated deflagration cylinder test, and is similar to several other thermal explosion tests. The primary difference is the passive velocimetry diagnostic, which enables measurement of confinement vessel wall velocities at failure, regardless of the timing and location of ignition.

  7. Diagnostic accuracy of NicAlert cotinine test strips in saliva for verifying smoking status.

    PubMed

    Cooke, Fiona; Bullen, Chris; Whittaker, Robyn; McRobbie, Hayden; Chen, Mei-Hua; Walker, Natalie

    2008-04-01

    Semiquantitative immunoassay technology, in the form of rapid test strips, offers a less time-consuming and less costly alternative to other methods of verifying self-reported smoking status, such as gas chromatography-nitrogen phosphorus detection (GC). Unfortunately, information on the validity and reliability of some test strips in urine and saliva samples is not always available. This paper describes the diagnostic accuracy of one type of test strip currently available (NicAlert cotinine test strips; NCTS). GC was used as the reference standard and saliva as the sample medium. The study involved 86 people (41 smokers and 45 nonsmokers) aged 18 years or over, who were able to understand written English and provide written consent. Pregnant women, women with infants less than 6 weeks old, and people who had eaten 30 min prior to sample collection were excluded. Two saliva samples were collected simultaneously from each participant, with one sample tested using NCTS and the other by GC analysis. People with at least 10 ng/ml cotinine (in both tests) in their saliva were considered smokers. NCTS were found to have a specificity of 95% (95% CI 89%-100%), a sensitivity of 93% (95% CI 85%-100%), a positive predictive value of 95% (95% CI 89%-100%), and a negative predictive value of 93% (95% CI 86%-100%). The use of NCTS is a valid and reliable method, compared with GC, to test saliva samples for verification of smoking status.

  8. Epidemiology of meningitis with a negative CSF Gram stain: under-utilization of available diagnostic tests.

    PubMed

    Nesher, L; Hadi, C M; Salazar, L; Wootton, S H; Garey, K W; Lasco, T; Luce, A M; Hasbun, R

    2016-01-01

    Meningitis with a negative cerebrospinal fluid Gram stain (CSF-GS) poses a diagnostic challenge as more than 50% of patients remain without an aetiology. The introduction of polymerase chain reaction (PCR) and arboviral serologies have increased diagnostic capabilities, yet large scale epidemiological studies evaluating their use in clinical practice are lacking. We conducted a prospective observational study in New Orleans between November 1999 and September 2008 (early era) when PCR was not widely available, and in Houston between November 2008 and June 2013 (modern era), when PCR was commonly used. Patients presenting with meningitis and negative CSF-GS were followed for 4 weeks. All investigations, PCR used, and results were recorded as they became available. In 323 patients enrolled, PCR provided the highest diagnostic yield (24·2%) but was ordered for 128 (39·6%) patients; followed by serology for arboviruses (15%) that was ordered for 100 (31%) of all patients. The yield of blood cultures was (10·3%) and that of CSF cultures was 4%; the yield for all other tests was <10%. Overall, 65% of the patients remained without a diagnosis at 4 weeks: 72·1% in early era vs. 53·4% (P < 0·01) in modern era; this change was attributed to diagnosing more viral pathogens, 8·3% and 26·3% (P < 0·01), respectively. The introduction of PCR and arboviral serologies has improved the yield of diagnosing patients with meningitis and a negative CSF-GS, but both tests are being under-utilized.

  9. Do high rates of empirical treatment undermine the potential effect of new diagnostic tests for tuberculosis in high-burden settings?

    PubMed

    Theron, Grant; Peter, Jonny; Dowdy, David; Langley, Ivor; Squire, S Bertel; Dheda, Keertan

    2014-06-01

    In tuberculosis-endemic settings, patients are often treated empirically, meaning that they are placed on treatment based on clinical symptoms or tests that do not provide a microbiological diagnosis (eg, chest radiography). New tests for tuberculosis, such as the Xpert MTB/RIF assay (Cepheid, Sunnyvale, CA, USA), are being implemented at substantial cost. To inform policy and rationally drive implementation, data are needed for how these tests affect morbidity, mortality, transmission, and population-level tuberculosis burden. If people diagnosed by use of new diagnostics would have received empirical treatment a few days later anyway, then the incremental benefit might be small. Will new diagnostics substantially improve outcomes and disease burden, or simply displace empirical treatment? Will the extent and accuracy of empirical treatment change with the introduction of a new test? In this Personal View, we review emerging data for how empirical treatment is frequently same-day, and might still be the predominant form of treatment in high-burden settings, even after Xpert implementation; and how Xpert might displace so-called true-positive, rather than false-positive, empirical treatment. We suggest types of studies needed to accurately assess the effect of new tuberculosis tests and the role of empirical treatment in real-world settings. Until such questions can be addressed, and empirical treatment is appropriately characterised, we postulate that the estimated population-level effect of new tests such as Xpert might be substantially overestimated.

  10. Self diagnostic accelerometer ground testing on a C-17 aircraft engine

    NASA Astrophysics Data System (ADS)

    Tokars, Roger P.; Lekki, John D.

    The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. Sensor system malfunction is a significant contributor to propulsion in flight shutdowns (IFSD) which can lead to aircraft accidents when the issue is compounded with an inappropriate crew response. The development of the SDA is important for both reducing the IFSD rate, and hence reducing the rate at which this component failure type can put an aircraft in jeopardy, and also as a critical enabling technology for future automated malfunction diagnostic systems. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to making vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. In an effort toward demonstrating the SDA's flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The two SDA attachment conditions used were fully tight and loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first time the robustness of the SDA in an engine environment characterized by high vibration levels.

  11. Self Diagnostic Accelerometer Ground Testing on a C-17 Aircraft Engine

    NASA Technical Reports Server (NTRS)

    Tokars, Roger P.; Lekki, John D.

    2013-01-01

    The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. Sensor system malfunction is a significant contributor to propulsion in flight shutdowns (IFSD) which can lead to aircraft accidents when the issue is compounded with an inappropriate crew response. The development of the SDA is important for both reducing the IFSD rate, and hence reducing the rate at which this component failure type can put an aircraft in jeopardy, and also as a critical enabling technology for future automated malfunction diagnostic systems. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to making vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. In an effort toward demonstrating the SDAs flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The two SDA attachment conditions used were fully tight and loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first time the robustness of the SDA in an engine environment characterized by high vibration levels.

  12. Diagnostic accuracy of bedside tests for predicting difficult intubation in Indian population: An observational study

    PubMed Central

    Dhanger, Sangeeta; Gupta, Suman Lata; Vinayagam, Stalin; Bidkar, Prasanna Udupi; Elakkumanan, Lenin Babu; Badhe, Ashok Shankar

    2016-01-01

    Background: Unanticipated difficult intubation can be challenging to anesthesiologists, and various bedside tests have been tried to predict difficult intubation. Aims: The aim of this study was to determine the incidence of difficult intubation in the Indian population and also to determine the diagnostic accuracy of bedside tests in predicting difficult intubation. Settings and Design: In this study, 200 patients belonging to age group 18–60 years of American Society of Anesthesiologists I and II, scheduled for surgery under general anesthesia requiring endotracheal intubation were enrolled. Patients with upper airway pathology, neck mass, and cervical spine injury were excluded from the study. Materials and Methods: An attending anesthesiologist conducted preoperative assessment and recorded parameters such as body mass index, modified Mallampati grading, inter-incisor distance, neck circumference, and thyromental distance (NC/TMD). After standard anesthetic induction, laryngoscopy was performed, and intubation difficulty assessed using intubation difficulty scale on the basis of seven variables. Statistical Analysis: The Chi-square test or student t-test was performed when appropriate. The binary multivariate logistic regression (forward-Wald) model was used to determine the independent risk factors. Results: Among the 200 patients, 26 patients had difficult intubation with an incidence of 13%. Among different variables, the Mallampati score and NC/TMD were independently associated with difficult intubation. Receiver operating characteristic curve showed a cut-off point of 3 or 4 for Mallampati score and 5.62 for NC/TMD to predict difficult intubation. Conclusion: The diagnostic accuracy of NC/TM ratio and Mallampatti score were better compared to other bedside tests to predict difficult intubation in Indian population. PMID:26957691

  13. McNemar chi2 test revisited: comparing sensitivity and specificity of diagnostic examinations.

    PubMed

    Trajman, A; Luiz, R R

    2008-01-01

    When evaluating a novel diagnostic examination for clinical use, it should be compared with a reference standard, defined as the best available examination, which may include clinical and laboratory criteria. The novel examination and reference standard's results are usually presented in the form of a 2 x 2 table, which allows calculation of sensitivity, specificity and accuracy. It has been recommended that the measures of statistical uncertainty should be reported, such as the 95% confidence interval, when evaluating the accuracy of diagnostic examinations. Comparing the difference in sensitivity or specificity of a novel examination with the reference standard is important when evaluating its usefulness. The McNemar chi(2) test, used to compare discordance of two dichotomous responses, can be applied for this purpose. However, applying the McNemar test to a 2 x 2 table for comparing the accuracy of examinations is not recommended, since this test is sensitive to the proportion of positive versus negative subjects. Moreover, if the novel examination has higher sensitivity than the one considered as the reference standard, constructing a classic 2 x 2 table would result in low specificity of the novel examination. Thus, in order to compare sensitivities and specificities between examinations, this table is inappropriate and an independent reference standard is necessary. In this article, we propose the use of the McNemar chi(2) test to compare sensitivities between examinations using a 2 x 2 table exclusively among diseased patients, defined by a set of criteria and follow-up of patients. Likewise, specificities can be compared applying the McNemar test among healthy individuals.

  14. Development of three-tier heat, temperature and internal energy diagnostic test

    NASA Astrophysics Data System (ADS)

    Gurcay, Deniz; Gulbas, Etna

    2015-05-01

    Background:Misconceptions are major obstacles to learning physics, and the concepts of heat and temperature are some of the common misconceptions that are encountered in daily life. Therefore, it is important to develop valid and reliable tools to determine students' misconceptions about basic thermodynamics concepts. Three-tier tests are effective assessment tools to determine misconceptions in physics. Although a limited number of three-tier tests about heat and temperature are discussed in the literature, no reports discuss three-tier tests that simultaneously consider heat, temperature and internal energy. Purpose:The aim of this study is to develop a valid and reliable three-tier test to determine students' misconceptions about heat, temperature and internal energy. Sample:The sample consists of 462 11th-grade Anatolian high school students. Of the participants, 46.8% were female and 53.2% were male. Design and methods:This research takes the form of a survey study. Initially, a multiple-choice test was developed. To each multiple-choice question was added one open-ended question asking the students to explain their answers. This test was then administered to 259 high school students and the data were analyzed both quantitatively and qualitatively. The students' answers for each open-ended question were analyzed and used to create the choices for the second-tier questions of the test. Depending on those results, a three-tier Heat, Temperature and Internal Energy Diagnostic Test (HTIEDT) was developed by adding a second-tier and certainty response index to each item. This three-tier test was administered to the sample of 462 high school students. Results:The Cronbach alpha reliability for the test was estimated for correct and misconception scores as .75 and .68, respectively. The results of the study suggested that HTIEDT could be used as a valid and reliable test in determining misconceptions about heat, temperature and internal energy concepts.

  15. Diagnostic test accuracy of glutamate dehydrogenase for Clostridium difficile: Systematic review and meta-analysis

    PubMed Central

    Arimoto, Jun; Horita, Nobuyuki; Kato, Shingo; Fuyuki, Akiko; Higurashi, Takuma; Ohkubo, Hidenori; Endo, Hiroki; Takashi, Nonaka; Kaneko, Takeshi; Nakajima, Atsushi

    2016-01-01

    We performed this systematic review and meta-analysis to assess the diagnostic accuracy of detecting glutamate dehydrogenase (GDH) for Clostridium difficile infection (CDI) based on the hierarchical model. Two investigators electrically searched four databases. Reference tests were stool cell cytotoxicity neutralization assay (CCNA) and stool toxigenic culture (TC). To assess the overall accuracy, we calculated the diagnostic odds ratio (DOR) using a DerSimonian-Laird random-model and area the under hierarchical summary receiver operating characteristics (AUC) using Holling’s proportional hazard models. The summary estimate of the sensitivity and the specificity were obtained using the bivariate model. According to 42 reports consisting of 3055 reference positive comparisons, and 26188 reference negative comparisons, the DOR was 115 (95%CI: 77–172, I2 = 12.0%) and the AUC was 0.970 (95%CI: 0.958–0.982). The summary estimate of sensitivity and specificity were 0.911 (95%CI: 0.871–0.940) and 0.912 (95%CI: 0.892–0.928). The positive and negative likelihood ratios were 10.4 (95%CI 8.4–12.7) and 0.098 (95%CI 0.066–0.142), respectively. Detecting GDH for the diagnosis of CDI had both high sensitivity and specificity. Considering its low cost and prevalence, it is appropriate for a screening test for CDI. PMID:27418431

  16. Monocyte Activation in Immunopathology: Cellular Test for Development of Diagnostics and Therapy

    PubMed Central

    Ivanova, Ekaterina A.; Orekhov, Alexander N.

    2016-01-01

    Several highly prevalent human diseases are associated with immunopathology. Alterations in the immune system are found in such life-threatening disorders as cancer and atherosclerosis. Monocyte activation followed by macrophage polarization is an important step in normal immune response to pathogens and other relevant stimuli. Depending on the nature of the activation signal, macrophages can acquire pro- or anti-inflammatory phenotypes that are characterized by the expression of distinct patterns of secreted cytokines and surface antigens. This process is disturbed in immunopathologies resulting in abnormal monocyte activation and/or bias of macrophage polarization towards one or the other phenotype. Such alterations could be used as important diagnostic markers and also as possible targets for the development of immunomodulating therapy. Recently developed cellular tests are designed to analyze the phenotype and activity of living cells circulating in patient's bloodstream. Monocyte/macrophage activation test is a successful example of cellular test relevant for atherosclerosis and oncopathology. This test demonstrated changes in macrophage activation in subclinical atherosclerosis and breast cancer and could also be used for screening a panel of natural agents with immunomodulatory activity. Further development of cellular tests will allow broadening the scope of their clinical implication. Such tests may become useful tools for drug research and therapy optimization. PMID:26885534

  17. DVA as a Diagnostic Test for Vestibulo-Ocular Reflex Function

    NASA Technical Reports Server (NTRS)

    Wood, Scott J.; Appelbaum, Meghan

    2010-01-01

    The vestibulo-ocular reflex (VOR) stabilizes vision on earth-fixed targets by eliciting eyes movements in response to changes in head position. How well the eyes perform this task can be functionally measured by the dynamic visual acuity (DVA) test. We designed a passive, horizontal DVA test to specifically study the acuity and reaction time when looking in different target locations. Visual acuity was compared among 12 subjects using a standard Landolt C wall chart, a computerized static (no rotation) acuity test and dynamic acuity test while oscillating at 0.8 Hz (+/-60 deg/s). In addition, five trials with yaw oscillation randomly presented a visual target in one of nine different locations with the size and presentation duration of the visual target varying across trials. The results showed a significant difference between the static and dynamic threshold acuities as well as a significant difference between the visual targets presented in the horizontal plane versus those in the vertical plane when comparing accuracy of vision and reaction time of the response. Visual acuity increased proportional to the size of the visual target and increased between 150 and 300 msec duration. We conclude that dynamic visual acuity varies with target location, with acuity optimized for targets in the plane of rotation. This DVA test could be used as a functional diagnostic test for visual-vestibular and neuro-cognitive impairments by assessing both accuracy and reaction time to acquire visual targets.

  18. Ancillary testing, diagnostic/classification criteria and severity grading in Behçet disease.

    PubMed

    Okada, Annabelle A; Stanford, Miles; Tabbara, Khalid

    2012-12-01

    Since there is no pathognomonic clinical sign or laboratory test to distinguish Behçet disease from other uveitic entities, the diagnosis must be made based on characteristic ocular and systemic findings in the absence of evidence of other disease that can explain the findings. Ancillary tests, including ocular and brain imaging studies, are used to assess the severity of intraocular inflammation and systemic manifestations of Behçet disease, to identify latent infections and other medical conditions that might worsen with systemic treatment, and to monitor for adverse effects of drugs used. There are two diagnostic or classification criteria in general use by the uveitis community, one from Japan and one from an international group; both rely on a minimum number and/or combination of clinical findings to identify Behçet disease. Finally, several grading schemes have been proposed to assess severity of ocular disease and response to treatment.

  19. B-type natriuretic peptide rapid assay: a diagnostic test for heart failure.

    PubMed

    Ancheta, Irma B

    2006-01-01

    Hospitals are constantly besieged with congestive heart failure admissions. Current studies show that the advent of the B-type natriuretic peptide (BNP) rapid assay as a quick and easy blood test is beneficial to nurses in confirming the diagnosis of heart failure. B-type natriuretic peptide is a neurohormone produced by the failing heart in response to increased volume and cardiac overload. The BNP rapid assay measures the presence of BNP levels present in the circulating bloodstream to confirm the diagnosis of congestive heart failure. It is a simple blood test that can be done at the bedside or at the clinic so it is a valid point-of-care modality. Elevated levels suggest severity of heart failure and possibility of sudden death. This article focuses on the description of the diagnostic performance of the BNP rapid assay, its clinical dimensions, and its implications to nursing practice and collaborative practice models.

  20. How diagnostic tests help to disentangle the mechanisms underlying neuropathic pain symptoms in painful neuropathies.

    PubMed

    Truini, Andrea; Cruccu, Giorgio

    2016-02-01

    Neuropathic pain, ie, pain arising directly from a lesion or disease affecting the somatosensory afferent pathway, manifests with various symptoms, the commonest being ongoing burning pain, electrical shock-like sensations, and dynamic mechanical allodynia. Reliable insights into the mechanisms underlying neuropathic pain symptoms come from diagnostic tests documenting and quantifying somatosensory afferent pathway damage in patients with painful neuropathies. Neurophysiological investigation and skin biopsy studies suggest that ongoing burning pain primarily reflects spontaneous activity in nociceptive-fiber pathways. Electrical shock-like sensations presumably arise from high-frequency ectopic bursts generated in demyelinated, nonnociceptive, Aβ fibers. Although the mechanisms underlying dynamic mechanical allodynia remain debatable, normally innocuous stimuli might cause pain by activating spared and sensitized nociceptive afferents. Extending the mechanistic approach to neuropathic pain symptoms might advance targeted therapy for the individual patient and improve testing for new drugs.

  1. The sensitivity and specificity of a diagnostic test of sequence-space synesthesia.

    PubMed

    Rothen, Nicolas; Jünemann, Kristin; Mealor, Andy D; Burckhardt, Vera; Ward, Jamie

    2016-12-01

    People with sequence-space synesthesia (SSS) report stable visuo-spatial forms corresponding to numbers, days, and months (amongst others). This type of synesthesia has intrigued scientists for over 130 years but the lack of an agreed upon tool for assessing it has held back research on this phenomenon. The present study builds on previous tests by measuring the consistency of spatial locations that is known to discriminate controls from synesthetes. We document, for the first time, the sensitivity and specificity of such a test and suggest a diagnostic cut-off point for discriminating between the groups based on the area bounded by different placement attempts with the same item.

  2. Development and Application of a Three-Tier Diagnostic Test to Assess Secondary Students' Understanding of Waves

    ERIC Educational Resources Information Center

    Caleon, Imelda; Subramaniam, R.

    2010-01-01

    This study focused on the development and application of a three-tier multiple-choice diagnostic test (or three-tier test) on the nature and propagation of waves. A question in a three-tier test comprises the "content tier", which measures content knowledge; the "reason tier", which measures explanatory knowledge; and the…

  3. The Diagnostic Accuracy of a New Test of Early Nonword Repetition for Differentiating Late Talking and Typically Developing Children

    ERIC Educational Resources Information Center

    Stokes, Stephanie F.; Klee, Thomas

    2009-01-01

    Purpose: To assess the diagnostic accuracy of a new Test of Early Nonword Repetition (TENR) for 2-year-old children. Method: 232 British-English-speaking children aged 27 ([plus or minus] 3) months were assessed on 3 standardized tests (receptive and expressive vocabulary and visual processing) and a novel nonword repetition (NWR) test. Parents…

  4. State of the art syphilis diagnostics: rapid point-of-care tests.

    PubMed

    Kay, Natasha S; Peeling, Rosanna W; Mabey, David C

    2014-01-01

    Syphilis remains an important and entirely preventable cause of stillbirth and neonatal mortality. More than 1 million women with active syphilis become pregnant each year. Without treatment, 25% of them will deliver a stillborn baby, 33% will deliver a live low-birth weight baby with an increased chance of dying in the first month of life. Adverse pregnancy outcomes due to syphilis can be prevented by screening pregnant women, and treating those who test positive with a single dose of penicillin before 28 weeks gestation. Until recently access to screening in low- and middle-income countries has been limited, since screening tests have been laboratory based, requiring equipment, electricity and trained laboratory staff. Now a number of rapid, cheap, simple and accurate screening tests are available and can give a result in 15-20 min, enabling those who require treatment to be treated at their first visit.

  5. Introducing malaria rapid diagnostic tests in private medicine retail outlets: A systematic literature review

    PubMed Central

    Visser, Theodoor; Bruxvoort, Katia; Maloney, Kathleen; Leslie, Toby; Barat, Lawrence M.; Allan, Richard; Ansah, Evelyn K.; Anyanti, Jennifer; Boulton, Ian; Clarke, Siân E.; Cohen, Jessica L.; Cohen, Justin M.; Cutherell, Andrea; Dolkart, Caitlin; Eves, Katie; Fink, Günther; Goodman, Catherine; Hutchinson, Eleanor; Lal, Sham; Mbonye, Anthony; Onwujekwe, Obinna; Petty, Nora; Pontarollo, Julie; Poyer, Stephen; Schellenberg, David; Streat, Elizabeth; Ward, Abigail; Wiseman, Virginia; Whitty, Christopher J. M.; Yeung, Shunmay; Cunningham, Jane; Chandler, Clare I. R.

    2017-01-01

    Background Many patients with malaria-like symptoms seek treatment in private medicine retail outlets (PMR) that distribute malaria medicines but do not traditionally provide diagnostic services, potentially leading to overtreatment with antimalarial drugs. To achieve universal access to prompt parasite-based diagnosis, many malaria-endemic countries are considering scaling up malaria rapid diagnostic tests (RDTs) in these outlets, an intervention that may require legislative changes and major investments in supporting programs and infrastructures. This review identifies studies that introduced malaria RDTs in PMRs and examines study outcomes and success factors to inform scale up decisions. Methods Published and unpublished studies that introduced malaria RDTs in PMRs were systematically identified and reviewed. Literature published before November 2016 was searched in six electronic databases, and unpublished studies were identified through personal contacts and stakeholder meetings. Outcomes were extracted from publications or provided by principal investigators. Results Six published and six unpublished studies were found. Most studies took place in sub-Saharan Africa and were small-scale pilots of RDT introduction in drug shops or pharmacies. None of the studies assessed large-scale implementation in PMRs. RDT uptake varied widely from 8%-100%. Provision of artemisinin-based combination therapy (ACT) for patients testing positive ranged from 30%-99%, and was more than 85% in five studies. Of those testing negative, provision of antimalarials varied from 2%-83% and was less than 20% in eight studies. Longer provider training, lower RDT retail prices and frequent supervision appeared to have a positive effect on RDT uptake and provider adherence to test results. Performance of RDTs by PMR vendors was generally good, but disposal of medical waste and referral of patients to public facilities were common challenges. Conclusions Expanding services of PMRs to

  6. The use of rapid dengue diagnostic tests in a routine clinical setting in a dengue-endemic area of Colombia

    PubMed Central

    Osorio, Lyda; Uribe, Marcela; Ardila, Gloria Ines; Orejuela, Yaneth; Velasco, Margarita; Bonelo, Anilza; Parra, Beatriz

    2015-01-01

    There is insufficient evidence of the usefulness of dengue diagnostic tests under routine conditions. We sought to analyse how physicians are using dengue diagnostics to inform research and development. Subjects attending 14 health institutions in an endemic area of Colombia with either a clinical diagnosis of dengue or for whom a dengue test was ordered were included in the study. Patterns of test-use are described herein. Factors associated with the ordering of dengue diagnostic tests were identified using contingency tables, nonparametric tests and logistic regression. A total of 778 subjects were diagnosed with dengue by the treating physician, of whom 386 (49.5%) were tested for dengue. Another 491 dengue tests were ordered in subjects whose primary diagnosis was not dengue. Severe dengue classification [odds ratio (OR) 2.2; 95% confidence interval (CI) 1.1-4.5], emergency consultation (OR 1.9; 95% CI 1.4-2.5) and month of the year (OR 3.1; 95% CI 1.7-5.5) were independently associated with ordering of dengue tests. Dengue tests were used both to rule in and rule out diagnosis. The latter use is not justified by the sensitivity of current rapid dengue diagnostic tests. Ordering of dengue tests appear to depend on a combination of factors, including physician and institutional preferences, as well as other patient and epidemiological factors. PMID:25993399

  7. Thiopurine S-methyltransferase testing for averting drug toxicity: a meta-analysis of diagnostic test accuracy

    PubMed Central

    Zur, RM; Roy, LM; Ito, S; Beyene, J; Carew, C; Ungar, WJ

    2016-01-01

    Thiopurine S-methyltransferase (TPMT) deficiency increases the risk of serious adverse events in persons receiving thiopurines. The objective was to synthesize reported sensitivity and specificity of TPMT phenotyping and genotyping using a latent class hierarchical summary receiver operating characteristic meta-analysis. In 27 studies, pooled sensitivity and specificity of phenotyping for deficient individuals was 75.9% (95% credible interval (CrI), 58.3–87.0%) and 98.9% (96.3–100%), respectively. For genotype tests evaluating TPMT*2 and TPMT*3, sensitivity and specificity was 90.4% (79.1–99.4%) and 100.0% (99.9–100%), respectively. For individuals with deficient or intermediate activity, phenotype sensitivity and specificity was 91.3% (86.4–95.5%) and 92.6% (86.5–96.6%), respectively. For genotype tests evaluating TPMT*2 and TPMT*3, sensitivity and specificity was 88.9% (81.6–97.5%) and 99.2% (98.4–99.9%), respectively. Genotyping has higher sensitivity as long as TPMT*2 and TPMT*3 are tested. Both approaches display high specificity. Latent class meta-analysis is a useful method for synthesizing diagnostic test performance data for clinical practice guidelines. PMID:27217052

  8. The use of rapid diagnostic tests for transfusion infectious screening in Africa: a literature review.

    PubMed

    Pruett, Cristina R; Vermeulen, Marion; Zacharias, Pete; Ingram, Charlotte; Tayou Tagny, Claude; Bloch, Evan M

    2015-01-01

    Infectious risk associated with blood transfusion remains a major public health challenge in Africa, where prevalence rates of the major transfusion-transmissible infections (ie, hepatitis B, hepatitis C, human immunodeficiency virus, and syphilis) are among the highest in the world. Resource-limited blood services often operate with minimal predonation screening safeguards, prompting exclusive reliance on laboratory testing to mitigate infectious risk. Transfusion screening with rapid diagnostic tests (RDTs) has been adopted in areas that lack the capacity to support the routine use of more sophisticated technologies. However, uncertainty surrounding the performance of some RDTs in the field has spurred debate regarding their application to blood donation screening. Our review of the literature identified 17 studies that evaluated RDTs for the infectious screening of blood donors in Africa. The review highlights the variable performance of available RDTs and the importance of their use in a quality-assured manner. Deficiencies in performance observed with some RDTs underscore the need to validate test kits prior to use under field conditions with locally acquired samples. Suboptimal sensitivities of some available tests, specifically hepatitis B virus rapid assays, question their suitability in single-test algorithms, particularly in high-prevalence regions. Although RDTs have limitations, many of which can be addressed through improved training and quality systems, they are frequently the only viable option for infectious screening in resource-poor African countries. Therefore, additional studies and specific guidelines regarding the use of RDTs in the context of blood safety are needed.

  9. EM field and instrumentation diagnostics in support of the LFT&E HPM methodology testing

    SciTech Connect

    Anderson, R A; Nelson, S D

    1997-09-04

    The Naval Air Warfare Center, China Lake, under the direction of the DoD LFT&E Office performed a series of HPM tests for the purpose of exercising the HPM methodology for LFT&E applications. An AH-1S Cobra helicopter was used as the canonical test bed. The Air Force Research Lab (formally Phillips Lab) provided the wide-band source and the Army Research Lab provided the narrow-band used in the tests. LLNL provided the EM diagnostics used at the site for both test series. Our mission was to measure the radiated field from the sources, measure the fields inside the helicopter and the coupling onto various signal lines inside the helicopter, and to monitor the various system signal levels for "bird health" purposes. These experiments were performed during June of 1997 and consisted of exposing the test bed to a series of narrow-band and wide-band pulses from HPM sources. This report covers the measured radiated fields, the fields inside the helicopter, and the coupled signal levels. The radiated fields were measured over a region which spans the physical body of the helicopter. The fields inside the helicopter and the coupled fields were measured using a series of probes inside the helicopter and connected to the outside measurement system using fiber-optic cables. The helicopter effects data are presented in the main China Lake report.

  10. Summary of Glaucoma Diagnostic Testing Accuracy: An Evidence-Based Meta-Analysis

    PubMed Central

    Ahmed, Saad; Khan, Zainab; Si, Francie; Mao, Alex; Pan, Irene; Yazdi, Fatemeh; Tsertsvadze, Alexander; Hutnik, Cindy; Moher, David; Tingey, David; Trope, Graham E.; Damji, Karim F.; Tarride, Jean-Eric; Goeree, Ron; Hodge, William

    2016-01-01

    Background New glaucoma diagnostic technologies are penetrating clinical care and are changing rapidly. Having a systematic review of these technologies will help clinicians and decision makers and help identify gaps that need to be addressed. This systematic review studied five glaucoma technologies compared to the gold standard of white on white perimetry for glaucoma detection. Methods OVID® interface: MEDLINE® (In-Process & Other Non-Indexed Citations), EMBASE®, BIOSIS Previews®, CINAHL®, PubMed, and the Cochrane Library were searched. A gray literature search was also performed. A technical expert panel, information specialists, systematic review method experts and biostatisticians were used. A PRISMA flow diagram was created and a random effect meta-analysis was performed. Results A total of 2,474 articles were screened. The greatest accuracy was found with frequency doubling technology (FDT) (diagnostic odds ratio (DOR): 57.7) followed by blue on yellow perimetry (DOR: 46.7), optical coherence tomography (OCT) (DOR: 41.8), GDx (DOR: 32.4) and Heidelberg retina tomography (HRT) (DOR: 17.8). Of greatest concern is that tests for heterogeneity were all above 50%, indicating that cutoffs used in these newer technologies were all very varied and not uniform across studies. Conclusions Glaucoma content experts need to establish uniform cutoffs for these newer technologies, so that studies that compare these technologies can be interpreted more uniformly. Nevertheless, synthesized data at this time demonstrate that amongst the newest technologies, OCT has the highest glaucoma diagnostic accuracy followed by GDx and then HRT. PMID:27540437

  11. Helicobacter pylori diagnostic tests in children: review of the literature from 1999 to 2009.

    PubMed

    Guarner, Jeannette; Kalach, Nicolas; Elitsur, Yoram; Koletzko, Sibylle

    2010-01-01

    The array of tests that can be used for diagnosis of Helicobacter pylori infection is large, and it can be confusing to define which test to use particularly in children where results may not be comparable to those obtained in adult patients. Using PubMed, we reviewed the English literature from January 1999 to May 2009 to identify articles that determined sensitivity and specificity of H. pylori invasive and non-invasive diagnostic tests in children. We excluded articles that presented a review of the literature, abstracts, case reports, or series where children's results could not be separated from adult populations. Of the tissue based methods, rapid urease tests have better sensitivity than histology to detect presence of H. pylori; however, histology can detect the pathology associated with disease including gastritis, intestinal metaplasia, and other conditions that could be the cause of the child's symptoms. Culture of gastric tissues or stool has 100% specificity but sensitivity is low. Of the serologic tests, immunoblot has the best sensitivity. The urea breath tests have >75% sensitivity for detection of H. pylori before and after treatment. Immunoassays in stool using monoclonal antibodies have >95% sensitivity for detection of H. pylori before and after treatment. PCR testing can be performed in tissue and stool samples and can detect genes associated to antibiotic resistance. In summary, the current commercial non-invasive tests have adequate sensitivity and specificity for detecting the presence of H. pylori; however, endoscopy with histopathology is the only method that can detect H. pylori and lesions associated with the infection.

  12. Diagnostic accuracy of fecal immunochemical test in average- and familial-risk colorectal cancer screening

    PubMed Central

    Castro, Inés; Hernandez, Vicent; González-Mao, Carmen; Rivera, Concepción; Iglesias, Felipe; Alves, María Teresa; Cid, Lucía; Soto, Santiago; De-Castro, Luisa; Vega, Pablo; Hermo, Jose Antonio; Macenlle, Ramiro; Martínez, Alfonso; Estevez, Pamela; Cid, Estela; Herreros-Villanueva, Marta; Portillo, Isabel; Bujanda, Luis; Fernández-Seara, Javier

    2014-01-01

    Background There is little information about the fecal immunochemical test (FIT) in familial-risk colorectal cancer (CRC) screening. Objectives The objective of this article is to investigate whether FIT diagnostic accuracy for advanced neoplasia (AN) differs between average and familial-risk (first-degree relative) patients. Methods A total of 1317 consecutive participants (595 familial) who collected one stool sample before performing a colonoscopy as a CRC screening test were included. FIT diagnostic accuracy for AN was evaluated with Chi-square test at a 20 µg hemoglobin/g of feces cut-off value. Finally, we determined which variables were independently related to AN. Results An AN was found in 151 (11.5%) patients. The overall accuracy was not statistically different between both cohorts for AN (88.4%, 91.7%; p = 0.051). At the cut-off stablished, differences in FIT sensitivity (31.1%, 40.6%; p = 0.2) or specificity (96.5%, 97.3%; p = 0.1) were not statistically significant. Finally, independent variables such as sex (male) (odds ratio (OR) 2.1, 95% confidence interval (CI) 1.4–3.1), age (50–65, >65 years) (OR 2.1, 95% CI 1.1–4.3; OR 2.7, 95% CI 1.2–6.1), previous colonoscopy (OR 0.4, 95% CI 0.2–0.9) and FIT ≥20 µg/g feces (OR 17.7, 95% CI 10.8–29.1) were associated with AN diagnosis. Conclusions FIT accuracy for AN detection is equivalent in average and familial-risk CRC screening cohorts. PMID:25452848

  13. Malaria rapid diagnostic test evaluation at private retail pharmacies in Kumasi, Ghana

    PubMed Central

    Audu, Rauf; Anto, Berko Panyin; Koffuor, George Asumeng; Abruquah, Akua Afriyie; Buabeng, Kwame Ohene

    2016-01-01

    Objective: Malaria rapid diagnostic test (MRDT) provides a good alternative to malaria microscopy diagnosis, particularly in resource-constrained settings. This study therefore evaluated MRDT in private retail pharmacies (PRPs) as a critical step in community case malaria management. Methods: In a prospective, cross-over, validation survey at six PRPs in the Ashanti Region of Ghana, 1200 patients presenting with fever in the preceding 48 h were sampled. Fingerstick blood samples were collected for preparation of thick and thin blood films for malaria microscopy. Categorized patients (600 each) went through the processes of MRDT or presumptive diagnosis (PD) of malaria. The malaria disease prevalence of the study area was established. Selectivity (Se), specificity (Sp), positive predictive value (PPV) along with false discovery rate (FDR), and negative predictive value (NPV) along with the false omission rate (FOR), and diagnostic odds ratio (DOR) of MRDT were then calculated. Findings: While 43.0% tested positive using the MRDT, 57.0% tested negative. However, 62.0% MRDT-negative patients in addition to all the MRDT positives were given artemether-lumefantrine. Of those diagnosed by PD, 98.2% were prescribed with an antimalarial (microscopy however confirmed only 70.3% as positive). Se and Sp of the MRDT were 90.68 ± 11.18% and 98.68 ± 1.19%, respectively. Malaria prevalence was estimated to be 43.3%. PPV was 98.0%, FDR was 2.0%, NPV was 98.0%, FOR was 2.0%, and DOR was 2366.43. Conclusion: Results highlighted good performance of MRDTs at PRPs which could inform decision toward its implementation. PMID:27512708

  14. An Examination of the Predictive Validity of the Keymath Diagnostic Arithmetic Test and the Wide Range Achievement Test in Exceptional Children

    ERIC Educational Resources Information Center

    Kratochwill, Thomas R.; Demuth, Dennis M.

    1976-01-01

    Title I elementary school children (N=37) were administered the Arithmetic subtest of the Wide Range Achievement Test and the Key Math Diagnostic Arithmetic Test. One year later, the Metropolitan Achievement Test was administered. Correlations between the three measures are presented and discussed. (Author)

  15. Parallel Recovery in a Trilingual Speaker: The Use of the Bilingual Aphasia Test as a Diagnostic Complement to the Comprehensive Aphasia Test

    ERIC Educational Resources Information Center

    Green, David W.; Ruffle, Louise; Grogan, Alice; Ali, Nilufa; Ramsden, Sue; Schofield, Tom; Leff, Alex P.; Crinion, Jenny; Price, Cathy J.

    2011-01-01

    We illustrate the value of the Bilingual Aphasia Test in the diagnostic assessment of a trilingual speaker post-stroke living in England for whom English was a non-native language. The Comprehensive Aphasia Test is routinely used to assess patients in English, but only in combination with the Bilingual Aphasia Test is it possible and practical to…

  16. Diagnostic hematology of reptiles.

    PubMed

    Stacy, Nicole I; Alleman, A Rick; Sayler, Katherine A

    2011-03-01

    The hematologic evaluation of reptiles is an indispensable diagnostic tool in exotic veterinary practice. The diversity of reptile species, their characteristic physiologic features, and effects of intrinsic and extrinsic factors present unique challenges for accurate interpretation of the hemogram. Combining the clinical presentation with hematologic findings provides valuable information in the diagnosis and monitoring of disease and helps guide the clinician toward therapy and further diagnostic testing. This article outlines the normal and pathologic morphology of blood cells of reptile species. The specific comparative aspects of reptiles are emphasized, and structural and functional abnormalities in the reptilian hemogram are described.

  17. Mycobacterium tuberculosis pili (MTP), a putative biomarker for a tuberculosis diagnostic test.

    PubMed

    Naidoo, Natasha; Ramsugit, Saiyur; Pillay, Manormoney

    2014-05-01

    Novel biomarkers are urgently needed for point of care TB diagnostics. In this study, we investigated the potential of the pilin subunit protein encoded by the mtp gene as a diagnostic biomarker. BLAST analysis of the mtp gene on published genome databases, and amplicon sequencing were performed in Mycobacterium tuberculosis Complex (MTBC) strains and other organisms. The protein secondary structure of the amino acid sequences of non-tuberculous Mycobacteria that partially aligned with the mtp sequence was analysed with PredictProtein software. The mtp gene and corresponding amino acid sequence of MTBC were 100% homologous with H37Rv, in contrast to the partial alignment of the non-tuberculous Mycobacteria. The mtp gene was present in all 91 clinical isolates of MTBC. Except for 2 strains with point mutations, the sequence was 100% conserved among the clinical strains. The mtp gene could not be amplified in all non-tuberculous Mycobacteria and respiratory organisms. The predicted MTP protein structure of Mycobacterium avium, Mycobacterium ulcerans and Mycobacterium abscessus differed significantly from that of the M. tuberculosis, which was similar to Mycobacterium marinum. The absence of the mtp gene in non-tuberculous Mycobacteria and other respiratory bacteria suggests that its encoded product, the pilin subunit protein of M. tuberculosis may be a suitable marker for a point of care TB test.

  18. The evolution of whole field optical diagnostics for external transonic testing

    NASA Astrophysics Data System (ADS)

    Fry, K. A.; Bryanston-Cross, P.

    1992-09-01

    The diagnostic use of quantitative laser flow visualization techniques has increased rapidly over recent years. The limitations imposed by conventional single point techniques such as laser Doppler anemometry are addressed and how they have been overcome by the development of a new family of whole field measurement techniques is demonstrated. In particular near instantaneous whole field velocity data was obtained in a relatively hostile, industrial 2.74 m x 2.44 m transonic wind tunnel (TWT) at the Aircraft Research Association (ARA). The techniques were evaluated for their suitability for making quantitative measurements in the wing/pylon region of a model wing and engine combination. Three optical diagnostic techniques were successfully developed within the context of the ARA facility. The first technique, laser light sheet (LLS), combines the operation of a pulse laser and video capture system to provide a 'real time' visualization of the flow, whereas a second pulse laser technique, Particle Image Velocimetry (PIV) can be used to make specific quantitative whole field instantaneous velocity measurements. The third method, holography, was used to produce a stored three dimensional visualization of the unsteady and shock wave features of the transonic flow in the gully region. A description is made of their installation and operation, and examples are presented of current test results.

  19. Meta-analyses of FibroTest diagnostic value in chronic liver disease

    PubMed Central

    Poynard, Thierry; Morra, Rachel; Halfon, Philippe; Castera, Laurent; Ratziu, Vlad; Imbert-Bismut, Françoise; Naveau, Sylvie; Thabut, Dominique; Lebrec, Didier; Zoulim, Fabien; Bourliere, Marc; Cacoub, Patrice; Messous, Djamila; Munteanu, Mona; de Ledinghen, Victor

    2007-01-01

    Background FibroTest (FT) is a biomarker of liver fibrosis initially validated in patients with chronic hepatitis C (CHC). The aim was to test two hypotheses, one, that the FT diagnostic value was similar in the three other frequent fibrotic diseases: chronic hepatitis B (CHB), alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD); and the other, that the FT diagnostic value was similar for intermediate and extreme fibrosis stages. Methods The main end points were the FT area under the ROC curves (AUROCs) for the diagnosis of bridging fibrosis (F2F3F4 vs. F0F1), standardized for the spectrum of fibrosis stages, and the comparison of FT AUROCs between adjacent stages. Two meta-analyses were performed: one combining all the published studies (random model), and one of an integrated data base combining individual data. Sensitivity analysis integrated the independency of authors, lenght of biopsy, prospective design, respect of procedures, comorbidities, and duration between biopsy and serum sampling. Results A total of 30 studies were included which pooled 6,378 subjects with both FT and biopsy (3,501 HCV, 1,457 HBV, 267 NAFLD, 429 ALD, and 724 mixed). Individual data were analyzed in 3,282 patients. The mean standardized AUROC was 0.84 (95% CI, 0.83–0.86), without differences between causes of liver disease: HCV 0.85 (0.82–0.87), HBV 0.80 (0.77–0.84), NAFLD 0.84 (0.76–0.92), ALD 0.86 (0.80–0.92), mixed 0.85 (0.80–0.93). The AUROC for the diagnosis of the intermediate adjacent stages F2 vs. F1 (0.66; 0.63–0.68, n = 2,055) did not differ from that of the extreme stages F3 vs. F4 (0.69; 0.65–0.72, n = 817) or F1 vs. F0 (0.62; 0.59–0.65, n = 1788). Conclusion FibroTest is an effective alternative to biopsy in patients with chronic hepatitis C and B, ALD and NAFLD. The FT diagnostic value is similar for the diagnosis of intermediate and extreme fibrosis stages. PMID:17937811

  20. Mixing tests: diagnostic aides in the investigation of prolonged prothrombin times and activated partial thromboplastin times.

    PubMed

    Kershaw, Geoffrey; Orellana, Daniel

    2013-04-01

    interpretations regarding "normalization." For this pivotal reason, standardized mixing test procedures and a consistent set of validated interpretive criteria represent the most favorable approach to maximizing the utility of a mixing test, and ensure the most accurate diagnosis for investigated patients.

  1. Influence of R wave analysis upon diagnostic accuracy of exercise testing in women.

    PubMed Central

    Ilsley, C; Canepa-Anson, R; Westgate, C; Webb, S; Rickards, A; Poole-Wilson, P

    1982-01-01

    Exercise electrocardiography in women with chest pain is associated with a high incidence of false positive ST segment depression. The recent observation that changes in R wave amplitude during exercise can also be used diagnostically may improve the value of stress testing in women. The results of 12 lead treadmill exercise and coronary angiography were reviewed in 62 women, mean age 51 years, presenting with "angina" without previous myocardial infarction. These were compared with exercise results in 14 healthy asymptomatic volunteers with a mean age of 26 years. In addition to conventional ST analysis, R wave amplitude changes during exercise, measured in leads II, III, a VF, and V4 to 6, were examined. While the sensitivity and specificity of ST and R wave changes were similar at about 67%, their combined interpretation was helpful. If both ST and R wave criteria were negative the predictive accuracy for normal coronary angiography was 94% (17/18). Alternatively, in tests showing both ST depression and an abnormal R wave response, coronary angiography was always abnormal (13/13). None of the normal volunteers developed ST segment depression and 93% (13/14) had a normal R wave response. If both were positive, however, coronary angiography was always abnormal (13/13). Although stress test interpretation in women is difficult, R wave analysis is a useful adjunct to ST change and can improve the predictive accuracy of the test in a significant number of patients. PMID:7093085

  2. [The lysate and recombinant antigens in ELISA-test-systems for diagnostic of herpes simplex].

    PubMed

    Ganova, L A; Kovtoniuk, G V; Korshun, L N; Kiseleva, E K; Tereshchenko, M I; Vudmaska, M I; Moĭsa, L N; Shevchuk, V A; Spivak, N Ia

    2014-08-01

    The lysate and recombinant antigens of various production included informula of ELISA-test-systems were analyzed. The ELISA-test-systems are used for detection of IgG to Herpes simplex virus type I and II. For testing the panel of serums PTH 201 (BBI Inc.) were used. The samples of this panel contain antibodies to Herpes simplex virus type I and II in mixed titers. The 69 serums of donors were used too (17 samples had IgG to Herpes simplex virus type I, 23 samples to Herpes simplex virus type II and 29 samples had no antibodies to Herpes simplex virus). The diagnostic capacity of mixture of recombinant antigens gG1 Herpes simplex virus type I and gG2 Herpes simplex virus type II (The research-and-production complex "DiaprofMed") was comparable with mixture of lysate antigen Herpes simplex virus type I and II (Membrane) EIE Antigen ("Virion Ltd."). In the test-systems for differentiation of IgG to Herpes simplex virus type I the recombinant antigen gG1 Herpes simplex virus type I proved to be comparable with commercial analogue Herpes simplex virus-1 gG1M ("Viral Therapeutics Inc."'). At the same time, capacity to detect IgG to Herpes simplex virus type II in recombinant protein gG2 Herpes simplex virus type II is significantly higher than in its analogue Herpes simplex virus-2 gG2c ("Viral Therapeutics Inc.").

  3. Idiopathic normal pressure hydrocephalus: diagnostic and predictive value of clinical testing, lumbar drainage, and CSF dynamics.

    PubMed

    Mahr, Cynthia V; Dengl, Markus; Nestler, Ulf; Reiss-Zimmermann, Martin; Eichner, Gerrit; Preuß, Matthias; Meixensberger, Jürgen

    2016-09-01

    OBJECTIVE The aim of the study was to analyze the diagnostic and predictive values of clinical tests, CSF dynamics, and intracranial pulsatility tests, compared with external lumbar drainage (ELD), for shunt response in patients with idiopathic normal pressure hydrocephalus (iNPH). METHODS Sixty-eight consecutive patients with suspected iNPH were prospectively evaluated. Preoperative assessment included clinical tests, overnight intracranial pressure (ICP) monitoring, lumbar infusion test (LIFT), and ELD for 24-72 hours. Simple and multiple linear regression analyses were conducted to identify predictive parameters concerning the outcome after shunt therapy. RESULTS Positive response to ELD correctly predicted improvement after CSF diversion in 87.9% of the patients. A Mini-Mental State Examination (MMSE) value below 21 was associated with nonresponse after shunt insertion (specificity 93%, sensitivity 67%). Resistance to outflow of CSF (ROut) > 12 mm Hg/ml/min was false negative in 21% of patients. Intracranial pulsatility parameters yielded different results in various parameters (correlation coefficient between pulse amplitude and ICP, slow wave amplitude, and mean ICP) but did not correlate to outcome. In multiple linear regression analysis, a calculation of presurgical MMSE versus the value after ELD, ROut, and ICP amplitude quotient during LIFT was significantly associated with outcome (p = 0.04). CONCLUSIONS Despite a multitude of invasive tests, presurgical clinical testing and response to ELD yielded the best prediction for improvement of symptoms following surgery. The complication rate of invasive testing was 5.4%. Multiple and simple linear regression analyses indicated that outcome can only be predicted by a combination of parameters, in accordance with a multifactorial pathogenesis of iNPH.

  4. Gaps in Guideline-Concordant Use of Diagnostic Tests Among Lung Cancer Patients

    PubMed Central

    Flanagan, Meghan R.; Varghese, Thomas K.; Backhus, Leah M.; Wood, Douglas E.; Mulligan, Michael S.; Cheng, Aaron M.; Flum, David R.; Farjah, Farhood

    2016-01-01

    Background Practice guidelines recommend routine use of pulmonary function tests (PFTs), computed tomography (CT), and positron emission tomography (PET) for the workup of resectable lung cancer patients. Little is known about the frequency of guideline concordance in routine practice. Methods A cohort study (2007 to 2013) of 15,951 lung cancer patients undergoing lobectomy or pneumonectomy was conducted with MarketScan, a claims database of individuals with employer-provided health insurance. Guideline concordance was defined by claims for PFT within 180 days of resection and for CT and PET within 90 days of resection. Generalized linear models were used to evaluate temporal trends, patient characteristics, and costs associated with guideline-concordant care. Results Overall, 61% of patients received guideline-concordant care, increasing from 57% in 2007 to 66% in 2013 (p < 0.001). Compared with patients who received guideline-discordant care, patients with guideline-concordant care more frequently underwent repeat testing (PFT: 21% versus 12%, p < 0.001; CT: 46% versus 22%, p < 0.001; PET: 2.3% versus 1.1%, p < 0.001). Health plan–adjusted mean total test-related costs were higher among guideline-concordant patients who underwent repeat testing than patients who did not ($4,304 versus $3,454, p < 0.001). Conclusions Forty percent of lung cancer patients treated with surgical procedures did not receive recommended noninvasive cancer staging and physiologic assessment before resection. Guideline concordance was associated with repeat testing, and repeat testing was associated with higher costs. These findings support the need for quality improvement interventions that can increase guideline concordance while curbing potential excess use of diagnostic tests. PMID:26507425

  5. A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

    ERIC Educational Resources Information Center

    Arslan, Harika Ozge; Cigdemoglu, Ceyhan; Moseley, Christine

    2012-01-01

    This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test…

  6. Application of Goubau Surface Wave Transmission Line for Improved Bench Testing of Diagnostic Beamline Elements

    SciTech Connect

    John Musson, Keith Cole, Sheldon Rubin

    2009-05-01

    In-air test fixtures for beamline elements typically utilize an X-Y positioning stage, and a wire antenna excited by an RF source. In most cases, the antenna contains a standing wave, and is useful only for coarse alignment measurements in CW mode. A surface-wave (SW) based transmission line permits RF energy to be launched on the wire, travel through the beamline component, and then be absorbed in a load. Since SW transmission lines employ travelling waves, the RF energy can be made to resemble the electron beam, limited only by ohmic losses and dispersion. Although lossy coaxial systems are also a consideration, the diameter of the coax introduces large uncertainties in centroid location. A SW wire is easily constructed out of 200 micron magnet wire, which more accurately approximates the physical profile of the electron beam. Benefits of this test fixture include accurate field mapping, absolute calibration for given beam currents, Z-axis independence, and temporal response measurements of sub-nanosecond pulse structures. Descriptions of the surface wave launching technique, transmission line, and instrumentation are presented, along with measurement data.

  7. Assessing the performance of spectroscopic models for cancer diagnostics using cross-validation and permutation testing

    NASA Astrophysics Data System (ADS)

    Lloyd, G. R.; Hutchings, J.; Almond, L. M.; Barr, H.; Kendall, C.; Stone, N.

    2012-01-01

    Multivariate classifiers (such as Linear Discriminant Analysis, Support Vector Machines etc) are known to be useful tools for making diagnostic decisions based on spectroscopic data. However, robust techniques for assessing their performance (e.g. by sensitivity and specificity) are vital if the application of these methods is to be successful in the clinic. In this work the application of repeated cross-validation for estimating confidence intervals for sensitivity and specificity of multivariate classifiers is presented. Furthermore, permutation testing is presented as a suitable technique for estimating the probability of obtaining the observed sensitivity and specificity by chance. Both approaches are demonstrated through their application to a Raman spectroscopic model of gastrointestinal cancer.

  8. [Use of group A streptococcal rapid diagnostic test in extra-pharyngeal infections].

    PubMed

    Wollner, A; Levy, C; Benani, M; Thollot, F; Béchet, S; Cohen, J; Bonacorsi, S; Bidet, Ph; Cohen, R

    2014-11-01

    The purpose of this study was to assess the performances of the group A streptococcus (GAS) rapid antigen diagnostic tests (RADTs) in extra-pharyngeal infections. Between October 2009 and June 2014, 368 patients (median age: 48 months) were enrolled. The pathologies involved were : 160 perineal infections (44 %), 69 blistering distal dactylitis (19 %), 55 cervical lymphadenitis (15 %), 31 crusty or bleeding rhinitis (8 %), and 53 other diseases (14 %). The sensitivity of GAS-RADT used was 96 % (95 % CI: 92-99 %), the specificity 81 % (95 % CI: 75- 86 %), the negative predictive value 97 % (CI 95 %: 93-99 %), and the positive predictive value 79 % (95 % CI: 73-85 %). Finally, positive and negative likelihood ratio were 5 (95 % CI: 4-7) and 0.05 (95 % CI: 0.02-0.11) respectively. The GAS-RADTs developed for pharyngitis have comparable performances in these settings and therefore can be used.

  9. Diagnostic validity of a neuropsychological test battery for Hispanic patients with epilepsy.

    PubMed

    Barr, William B; Bender, Heidi A; Morrison, Chris; Cruz-Laureano, Daniel; Vazquez, Blanca; Kuzniecky, Ruben

    2009-11-01

    The Neuropsychological Screening Battery for Hispanics (NeSBHIS) was developed to address the growing need for linguistically appropriate Spanish-language assessment measures. Despite the potential benefits to clinical practice, no prior study has assessed its diagnostic validity in populations with epilepsy. One hundred and fifteen patients with confirmed epilepsy were evaluated via the NeSBHIS; these data were standardized according to age- and education-based norms. Performance decrements were observed in more than 40% of participants on measures of processing speed and naming. Deficits in verbal and visual recall were also exhibited by 29 and 26% of the sample, respectively. No significant differences in test performance emerged between patients with VEEG evidence of left (N=48) versus right (N=24) temporal lobe epilepsy. Although the NeSBHIS is sensitive to the cognitive impairments commonly observed in populations with epilepsy, there are limitations to its ability to identify lateralized neuropsychological impairment in patients with temporal lobe epilepsy.

  10. A Diagnostic Test for Determining the Location of the GeV Emission in Powerful Blazars

    NASA Technical Reports Server (NTRS)

    Dotson, Amanda; Georganopoulos, Markos; Kazanas, Demosthenes; Perlman, Eric

    2011-01-01

    An issue currently under debate in the literature is how far from the black hole is the Fermi-observed GeV emission of powerful blazars emitted. Here we present a clear diagnostic tool for testing whether the Ge V emission site is located within the sub-pc broad emission line (BLR) region or further out in the few pc scale molecular torus (MT) environment. Within the BLR the scatteri takes place at the onset of the Klein-Nishina regime, causing the electron cooling time to become almost energy independent and as a result, the variation of high-energy emission is expected to be achromatic. Contrarily, if the emission site is located outside the BLR, the expected GeY variability is energy-dependent and with amplitude increasing with energy. We demonstrate this using time-dependent numerical simulations of blazar variability.

  11. [Improving malaria management through Rapid Diagnostic Tests: appropriation by providers communities (Sénégal)].

    PubMed

    Faye, S L

    2012-08-01

    Introduced in the public health services in Senegal since 2007, Rapid Diagnostic Tests (RDTs) are a new technical opportunity for clinical diagnosis of malaria. We analyze how different categories of caregivers, who are the providers, assume appropriation of their professional practices. Similarly, we document, from the analysis of their application for care, attitudes of recipients towards RDTs. The results show a time lag between the uses of this tool and the recommendations. RDTs have a recognized epidemiological usefulness. However, their positive integration requires a change in behaviors that caregivers and recipients are not always willing to assume. Indeed, the architecture, working conditions and applications for care influence the modes of appropriation of this technical innovation.

  12. Rapid fecal calprotectin testing to assess for endoscopic disease activity in inflammatory bowel disease: A diagnostic cohort study

    PubMed Central

    Kwapisz, Lukasz; Mosli, Mahmoud; Chande, Nilesh; Yan, Brian; Beaton, Melanie; Micsko, Jessica; Mennill, Pauline W.; Barnett, William; Bax, Kevin; Ponich, Terry; Howard, John; Tirolese, Anthony; Lannigan, Robert; Gregor, James

    2015-01-01

    Background and Aim: With increasing numbers of patients diagnosed with inflammatory bowel disease (IBD), it is important to identify noninvasive methods of detecting disease activity. The aim of this study is to examine the diagnostic accuracy of fecal rapid calprotectin (FC) testing in the detection of endoscopically active IBD. Patients and Methods: All consecutive patients presenting to outpatient clinics with lower gastrointestinal symptoms were prospectively recruited. Patients provided FC samples. Sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) for FC were calculated. Receiver–operator characteristics (ROC) curve was used to identify the ideal FC cutoff that predicts endoscopic disease activity. Correlation between FC and endoscopic disease activity, disease location, and C-reactive protein (CRP) levels were measured. Results: One hundred and twenty-six patients, of whom 52% were females, were included in the final analysis with a mean age of 44.4 ± 16.7 years. Comparing FC to endoscopic findings, the following results were calculated: A cutoff point of 100 μg/g showed Sn = 83%, Sp = 67%, PPV = 65%, and NPV = 85%; and 200 μg/g showed Sn = 66%, Sp = 82%, PPV = 73%, and NPV = 77%. Based on ROC curve, the best FC cutoff point to predict endoscopic disease activity was 140 μg/g. Using this reference, FC levels strongly correlated with colorectal, ileocolonic, and ileal disease and predicted endoscopic activity. Conclusions: FC is an accurate test when used as an initial screening tool for patients suspected of having active IBD. Given its noninvasive nature, it may prove to reduce the need for colonoscopy and be an added tool in the management of IBD. PMID:26655130

  13. IDH testing in diagnostic neuropathology: review and practical guideline article invited by the Euro-CNS research committee.

    PubMed

    Preusser, M; Capper, D; Hartmann, C

    2011-01-01

    Isocitrate dehydrogenase 1 (IDH1) gene mutations, primarily of the R132H type, occur in approximately 60 - 90% of diffuse and anaplastic gliomas and secondary glioblastomas. IDH mutations in gliomas are associated with several clinically relevant parameters including patient age, histopathological diagnosis, combined 1p/19q deletion, TP53 mutation, MGMT promoter hypermethylation and patient survival. Therefore, testing of the IDH status is relevant for diagnostic and prognostic considerations in primary brain tumors. IDH status can be assessed by immunohistochemistry or DNA-based methods including gene sequencing in the routine setting. Here, we review the relevance of IDH testing in diffuse gliomas and present practical instructions including detailed descriptions of procedures and protocols for diagnostic IDH testing using immunohistochemistry (for both automated and manual staining) and gene sequencing. Our article may provide guidance for laboratories aiming at establishing IDH testing for diagnostic evaluation of primary brain tumors.

  14. Selective pressures for accurate altruism targeting: evidence from digital evolution for difficult-to-test aspects of inclusive fitness theory.

    PubMed

    Clune, Jeff; Goldsby, Heather J; Ofria, Charles; Pennock, Robert T

    2011-03-07

    Inclusive fitness theory predicts that natural selection will favour altruist genes that are more accurate in targeting altruism only to copies of themselves. In this paper, we provide evidence from digital evolution in support of this prediction by competing multiple altruist-targeting mechanisms that vary in their accuracy in determining whether a potential target for altruism carries a copy of the altruist gene. We compete altruism-targeting mechanisms based on (i) kinship (kin targeting), (ii) genetic similarity at a level greater than that expected of kin (similarity targeting), and (iii) perfect knowledge of the presence of an altruist gene (green beard targeting). Natural selection always favoured the most accurate targeting mechanism available. Our investigations also revealed that evolution did not increase the altruism level when all green beard altruists used the same phenotypic marker. The green beard altruism levels stably increased only when mutations that changed the altruism level also changed the marker (e.g. beard colour), such that beard colour reliably indicated the altruism level. For kin- and similarity-targeting mechanisms, we found that evolution was able to stably adjust altruism levels. Our results confirm that natural selection favours altruist genes that are increasingly accurate in targeting altruism to only their copies. Our work also emphasizes that the concept of targeting accuracy must include both the presence of an altruist gene and the level of altruism it produces.

  15. Ocular myasthenia: evaluation of Tensilon tonography and electronystagmography as diagnostic tests

    PubMed Central

    Campbell, M. J.; Simpson, E.; Crombie, A. L.; Walton, J. N.

    1970-01-01

    The value of electronystagmography (ENG) and of tonography in monitoring the beneficial effect of edrophonium chloride (Tensilon) on the extraocular muscles in myasthenia gravis has been assessed. Studies were performed on 17 patients with myasthenia gravis and on 18 control subjects, of whom nine had extraocular muscle weakness due to myopathic or neurogenic lesions. Electronystagmography recorded the repetitive following movements of the eyes elicited during optokinetic nystagmus. Neuromuscular fatigue with the subsequent beneficial response to Tensilon was clearly seen in 50% of patients with myasthenia. False positive responses were not seen in control subjects but in many of these, as in the remaining myasthenic patients, the amplitude and rate of nystagmus seen in the ENG was very variable. These difficulties suggest that the ENG is of limited value as a diagnostic test in myasthenia gravis. Tonography, recording the intraocular pressure of the eye continuously over four minutes, was found to be of considerable value. We found that the intraocular pressure fell on average by 1·6 to 1·8 mm Hg over a one minute period in the control recordings but increased by a mean of 1·6 mm Hg in patients with myasthenia, with a peak effect 35 seconds after Tensilon. In only one patient was there a complete failure of response. This patient, and also another woman who showed a less striking response, had severe myasthenia with a fixed ocular weakness. It is suggested that an absence of any increase in tension with Tensilon may be seen in patients with permanent neostigmine-resistant myopathic change. A small false positive response was seen on one occasion only in a patient with a sympathetic nerve lesion. Tensilon tonography, as a simple painless procedure, would appear to be of considerable value in the diagnosis of ocular myasthenia and also as a diagnostic test in the exclusion of myasthenia as a cause of isolated extraocular neuromuscular weakness. PMID:4249171

  16. Post-and prenatal testing for FSHD: Diagnostic approach for sporadic and familial cases

    SciTech Connect

    Bakker, E.; Wielen, M.J.R. van der; Losekoot, M.

    1994-09-01

    Facioscapulohumeral muscular dystrophy (FSHD) is a progressive neuromuscular disorder. A major locus for FSHD was localized at the distal part of chromosome 4q. More recently, a disease associated DNA rearrangement was detected with the polymorphic probe p13E-11 (D4F104S1). In most FSHD patients, a shortened (< 28 kb instead of 50-300 kb) allele was detected. In sporadic patients a de novo deletion was found to be associated with the occurrence of FSHD. Diagnostically there were a number of problems to overcome. (1) About 5% of families show no linkage to chromosome 4q35. (2) Some 10% normal individuals show a shortened p13E11 allele, which is located at chromosome 10q. Our diagnostic strategy is as follows: If in sporadic patients a shortened p13E-11 allele is detected and neither parent shows this allele, then a de novo deletion has occurred and FSHD is proven. If no shortened allele is detected FSHD is less likely. In case one of the parents shows a shortened allele then clinical investigations and linkage studies are performed for both chromosome 4 and 10 markers. In familial cases both p13E-11 and polymorphic markers are tested. A shortened p13E-11 allele and/or chromosome 4 haplotype segregating with FSHD can be used for presymptomatic and prenatal diagnosis. Up to now, 45 sporadic cases and 21 families were referred for diagnosis. In 22 sporadic cases a shortened allele was detected, 13 were proven de novo. The first prenatal test was recently performed. The index patient was a de novo case with a shortened allele; the fetus had inherited this allele.

  17. Results from the Astronomy Diagnostic Test: 3 Years at MiraCosta College

    NASA Astrophysics Data System (ADS)

    Sirbaugh French, Rica

    2007-12-01

    The Astronomy Diagnostic Test 2.0 (ADT) was administered to 26 sections of ASTR 101 at MiraCosta College (MCC) from fall 2004 through summer 2007. MiraCosta is a two-year community college located in Oceanside, CA, USA (roughly 40 miles north of San Diego) with an enrollment of approximately 11,000 students. ASTR 101 is MiraCosta's introductory astronomy survey course for non-science majors and has no math prerequisite. Class sizes ranged from 10 to 38 students. Comparison with the ADT National Project results indicates similar pre- and post-course averages: 31.8% (MCC) vs. 32.4% (National) for pre-course tests and 49.3% (MCC) vs. 47.3% (National) for post-course tests. The sample sizes are 709 and 530 students for the pre- and post-tests, respectively. The normalized gain for the entire data set is 0.256 and the effect size (ES) is 1.04, meaning that approximately 85% of the post-test scores are above the average of the pre-test scores. Previous studies have shown the ADT to be a reliable indicator of pre-course misconceptions while post-course scores are useful for comparing modes of instruction and assessing student learning on a limited number of concepts. Additional analyses of the MCC data probe for trends with variables such as gender, class size, and implementation of materials designed for a more "learner-centered” approach (such as Lecture Tutorials, Ranking Tasks, and Think-Pair-Share questions), as well as gains for a particular subset of concepts.

  18. Exploring Secondary Students' Conceptions about Fire Using a Two-Tier, True/False, Easy-to-Use Diagnostic Test

    ERIC Educational Resources Information Center

    Potvin, Patrice; Skelling-Desmeules, Yannick; Sy, Ousmane

    2015-01-01

    This article describes the design of a misconception diagnostic test about fire-related phenomena. It proposes a new test format in which a certainty-measuring tier has been integrated into each of the true/false response choices. This format is argued to be easier for teachers to use than the increasingly popular three-tier format. First, we…

  19. Prior probability (the pretest best guess) affects predictive values of diagnostic tests.

    PubMed

    Erb, Hollis N

    2011-06-01

    Authors who publish evaluations of dichotomous (yes/no) diagnostic tests often include the predictive values of their test at a single prior probability (eg, the prevalence of the target disease within the evaluation data set). The objectives of this technical note are to demonstrate why single-probability predictive values are misleading and to show a better way to display positive predictive values (PPV) and negative predictive values (NPV) for a newly evaluated test. Secondly, this technical note will show readers how to calculate predictive values from only sensitivity and specificity for any desired prior probability. As prior probability increases from 0% to 100%, PPV increases from 0% to 100%, but NPV goes in the opposite direction (drops from 100% to 0%). Because prior probabilities vary so greatly across situations, predictive values should be provided in publications for the full range of potential prior probabilities (if provided at all). This is easily done with a 2-curve graph displaying the predictive values (y-axis) against the prior probability (x-axis).

  20. Safety and diagnostic systems on the Liquid Lithium Test Stand (LLTS)

    NASA Astrophysics Data System (ADS)

    Schwartz, J. A.; Jaworski, M. A.; Ellis, R.; Kaita, R.; Mozulay, R.

    2013-10-01

    The Liquid Lithium Test Stand (LLTS) is a test bed for development of flowing liquid lithium systems for plasma-facing components at PPPL. LLTS is designed to test operation of liquid lithium under vacuum, including flowing, solidifying (such as would be the case at the end of plasma operations), and re-melting. Constructed of stainless steel, LLTS is a closed loop of pipe with two reservoirs and a pump, as well as diagnostics for temperature, flow rate, and pressure. Since liquid lithium is a highly reactive material, special care must be taken when designing such a system. These include a permanent-magnet MHD pump and MHD flow meter that have no mechanical components in direct contact with the liquid lithium. The LLTS also includes an expandable 24-channel leak-detector interlock system which cuts power to heaters and the pump if any lithium leaks from a pipe joint. Design for the interlock systems and flow meter are presented. This work is supported by US DOE Contract DE-AC02-09CH11466.