Academic literature on the topic 'Youden’s Test'
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Journal articles on the topic "Youden’s Test"
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Logoyda, L. S. "YOUDEN'S TEST FOR CHROMATOGRAPHIC DETERMINATION OF ENALAPRIL IN PHARMACEUTICALS." International Journal of Medicine and Medical Research 5, no. 2 (2020): 83–87. http://dx.doi.org/10.11603/ijmmr.2413-6077.2019.2.10896.
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Background. Robustness tests were firstly introduced for avoiding problems in interlaboratory studies and identifying the factors potentially responsible. A robustness test performing in late validation procedure involves the possibility that when the method is established not robust, it should be redeveloped and optimized. At this stage much effort has been made and money spent for optimization and validation, and therefore avoiding this would be great.
 Objective. The aim of the study was to consider the robustness of HPLC determination of enalapril (in tablets) by the Youden’s test.
 Methods. Youden’s test was chosen as an efficient method to assess the robustness among all analytical methods that is by means of an experiment design, which involved seven analytical parameters combined in eight tests. In previous studies, we evaluated the chromatographic method robustness to quantify enalapril (in tablets) by Youden’s test.
 Results. According to the Youden’s test criteria, HPLC method proved to be greatly robust regarding the enalapril content in introduction of variation of seven analytic parameters. The lowest variation in enalapril content was 0.91 %, when Grace Platinumр C8 EPS column (4.6 mm i.d. X 250 mm, 5 μm) was used. A holistic approach concerning simultaneous innovations in particle technology and instrument design was endeavored for the first time to meet and tackle the analytical laboratory issues. This was aimed at promoting success of analytical scientists as well as profitability and productiveness of business.
 Conclusion. The Youden’s test has been proved to be an efficient and useful tool for evaluation of robustness of enalapril HPLC assay.
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Peleshok, K., O. Dutchak, and Fatma Abdelmalek Mohamed. "ROBUSTNESS EVALUATION OF THE CHROMATOGRAPHIC DETERMINATION OF VALSARTAN IN PHARMACEUTICALS." Здобутки клінічної і експериментальної медицини, no. 3 (September 29, 2020): 26–31. http://dx.doi.org/10.11603/1811-2471.2020.v.i3.11579.
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The robustness of an analytical procedure is a measure of its capacity to remain unaffected by small, but deliberate variations in method parameters and provides an indication of its reliability during normal usage.
 The aim of the study – to evaluate the rubustness of HPLC determination of valsartan in tablets using Youden’s test.
 Material and Methods. An efficient method to assess the robustness of analytical methodsis by Youden’s test, by means of an experiment design which involves seven analytical parameters combined in eight tests. In the recent studies, we assessed the robustness of a chromatographic method to quantify valsartan in tablets using Youden’s test.
 Results. The experimental design approach (design of experiment) is the method of simultaneous investigation of the influence of several factors on robustness of the method using a certain plan (matrix) of experiments. By using the Youden’s test criteria, HPLC method showed to be greatly robust concerning valsartan content, at the introduction of variation in seven analytic parameters. This was done in order to make analytical scientists more successful and businesses more profitable and productive.
 Conclusion. Youden’s test proved to be an efficient and helpful tool for the robustness evaluation for assay of valsartan by HPLC. Youden’s test can be applied successfully for the robustness evaluation in validation process of analytical methods.
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Hajian-Tilaki, Karimolla. "The choice of methods in determining the optimal cut-off value for quantitative diagnostic test evaluation." Statistical Methods in Medical Research 27, no. 8 (2017): 2374–83. http://dx.doi.org/10.1177/0962280216680383.
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Introduction The choice of criteria in determining optimal cut-off value is a matter of concern in quantitative diagnostic tests. Several indexes such as Youden’s index, Euclidean index, product of sensitivity and specificity in receiver operator characteristic space and diagnostic odds ratio have been used in clinical practices but their advantages and limitations are not well understood by clinicians. This study aimed to compare these methods in determining optimal cut-off values for quantitative diagnostic test. Methods The different configurations of binormal and bilogistic distributions with equal and unequal variances for nondiseased and diseased subjects were examined. The cut-off values with increment of 0.1 in Z-scale were varied. Then, the Youden’s index, Euclidean index, product of sensitivity and specificity, and diagnostic odds ratio were calculated over various cut-off values under distributional assumptions with confirmed parameters. Results According to the obtained data from binormal model and equal variances, the optimal cut-off values derived from Youden’s index, Euclidean index, and product method were similar but the diagnostic odds ratio yielded either extremely low or extremely high optimal cut-off value. For bilogistic pair distributions with equal variances, the Youden’s, Euclidean indexes and product method resulted in an identical cut-off value but the diagnostic odds ratio was constant over various cut-points. By both binormal and bilogistic data with more variations in nondiseased population, the Youden’s index produced a higher sensitive optimal cut-off value; but with more variation for diseased distribution, the Euclidean index showed a more sensitive optimal cut-off. For bilogistic data with unequal variance, the log(diagnostic odds ratio) had a straight line relationship over cut-off values with either positive or negative slope. Conclusion As a measure of association, diagnostic odds ratio cannot be informative in determining an optimal cut-off value. The advantage of receiver operator characteristic analysis to obtain the optimal cut-off value is to use Youden’s index, Euclidean index, or product index which is recommended. The choice between them depends on variability of test results in diseased and nondiseased subjects and the desired sensitivity.
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Hughes, G. "Youden’s Index and the Weight of Evidence Revisited." Methods of Information in Medicine 54, no. 06 (2015): 576–77. http://dx.doi.org/10.3414/me15-04-0007.
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SummaryA correspondence between Youden’s index for rating diagnostic tests and the log-likelihood ratio of a positive test outcome is illustrated by data calculated from two previously-published studies of binary tests.
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Hughes, G. "Youden's Index and the Weight of Evidence." Methods of Information in Medicine 54, no. 02 (2015): 198–99. http://dx.doi.org/10.3414/me14-04-0003.
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SummaryBy means of Shannon’s relationship between information and probability, Youden’s index for rating diagnostic tests is shown to be a probability-scale analogue of the log-likelihood ratio of a positive test outcome.
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Shulyak, N. S., A. D. Abbeyquaye, and D. B. Koval. "ROBUSTNESS EVALUATION OF HPLC DETERMINATION OF ATORVASTATIN AND LISINOPRIL ON COLUMN PUROSPHER C8 STAR IN PHARMACEUTICALS." Medical and Clinical Chemistry, no. 1 (May 22, 2021): 21–26. http://dx.doi.org/10.11603/mcch.2410-681x.2021.i1.12104.
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Introduction. Innovative pharmaceutical development of various antihypertensive drugs with statins and the creation of domestic fixed-dose combinations of drugs with different effects is an urgent task of modern pharmacy, which will help attract more patients to the treatment and prevention of cardiovascular disease. Pharmaceutical development of atorvastatin and lisinopril by our scientific group proposes for using the ratio of (1/1) for lisinopril (10 mg) and atorvastatin (10 mg). HPLC (High-Performance Liquid Chromatography) technique is adopted as it is considered as the most common technique in realm of quality control analysis.
 The aim of the study – to evaluate the robustness of HPLC (High-Performance Liquid Chromatography) method for the quantitation of lisinopril and atorvastatin and determine the analytical parameters that present greater influence in the final results of the analysis.
 Research Methods. An efficient method to assess the robustness of analytical methods is by Youden’s test, by means of an experiment design which involves seven analytical parameters combined in eight tests. In the recent studies, we assessed the robustness of a chromatographic method to quantify lisinopril and atorvastatin in tablets using Youden’s test.
 Results and Discussion. By using the criteria of Youden’s test, HPLC method proved to be greatly robust regarding content of lisinopril and atorvastatin, when variations in seven analytical parameters were introduced. The most variation in effects of the analytical parameters in retention time (Rt) for lisinopril and atorvastatin HPLC quantitation was when used column supplier. Purospher C8 STAR (55 mm x 4mm, 5 μm) is based on high purity silica and an almost complete surface coverage. Purospher C8 STAR provides excellent peak symmetry for acidic, basic and even chelating compounds, highest column efficiency in terms of the number of theoretical plates, and exceptional stability from pH 1.5 to 10.5.
 Conclusion. Youden’s test can be applied successfully for the robustness evaluation in validation process of analytical methods and results ontained in our work should be interest to the scientific population dealing with pharmaceutical analytical chemistry.
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Thanh, Pham Hai, Hoang Thu Uyen, Do Thi Thanh Toan, et al. "Reliability and validity of the Internet Gaming Disorder-20 Test among Vietnamese teenagers." Tạp chí Y học Dự phòng 31, no. 4 (2021): 118–28. http://dx.doi.org/10.51403/0868-2836/2021/344.
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To validate the Vietnamese version Internet Gaming Disorder-20 (VN-IGD-20) Test for teenagers, a survey among 349 gamers, who were accepted in the interview, from secondary and high schools from 28 game stores was conducted in Hanoi, Vietnam. The IGD-20 Test comprised 20 items with six different dimensions, using a 5-point Likert scale. Exploratory factor analysis (EFA) and confrmatory factor analysis (CFA) were used to examine the validation; Cronbach’s Alpha was performed to test the reliability; and Latent class analysis (LCA) was applied to identify the level of internet gaming disorder (IGD). Moreover, the ROC curve diagram was used with the highest Youden’s Index parameter to determine the best cut-off point. CFA proved that the VN-IGD-Test with 17 items, which was divided into fve-factor dimensions. The model indexes of the Vietnamese questionnaire included RMSEA = 0.053; SRMR = 0.052; GFI = 0.929; TLI = 0.908 and CFI = 0.927. The values for Cronbach’s alpha coeffcient of each dimension ranged from 0.823 to 0.840. The LCA found out four levels of IGD: casual gamers, regular gamers, low-risk engaged gamers, and high-risk engaged gamers. Additionally, the optimal empirical cut-off point with the highest Youden’s Index was 47.5 (out of 85). The present study fndings illustrated that the VN-IGD-17 Test could be used as a valid and reliable tool for assessing internet gaming disorder in Vietnamese teenagers.
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Tosic-Pajic, Jelena Zivadin, Predrag Sazdanovic, Marija Sorak, et al. "Chlamydia trachomatis screening in resource-limited countries – Comparison of diagnostic accuracy of 3 different assays." Journal of Infection in Developing Countries 12, no. 09 (2018): 733–40. http://dx.doi.org/10.3855/jidc.10442.
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Introduction: Commercially available assays were evaluated in order to determine diagnostic accuracy of Chlamydia trachomatis specific tests for screening.
 Methods: The study included 225 sexually active men and women, who were tested for genital chlamydial infection in Institute of Public Health Kragujevac. Three screening tests were used: direct immunofluorescence (DIF) and rapid lateral immunochromatographic test (RT) for qualitative detection of chlamydial antigens and immunoenzyme (ELISA) test for detection of serum levels of anti-chlamydial IgA and IgG antibodies. Diagnostic efficiency of these tests were determined in relation to results obtained by RT-PCR method.
 Results: Statistical significance between the results obtained by RT-PCR as a gold standard and DIF, RT and ELISA were analyzed using chi-square (χ2) test. Statistical analysis showed a significant difference between RT-PCR and analyzed screening tests: DIF (χ2 = 303; p < 0.001), RT (χ2 = 4.19; p = 0.041), serum IgA (χ2 = 4.19; p = 0.041) and serum IgG (χ2 = 67; p < 0.001) which indicates poor agreement between these tests. Large numbers of false positive (FP) and false negative (FN) results were observed for all tested assays. According to Youden’s index, serum IgG and DIF testing demonstrated the most-balanced sensitivity-specificity rate. RT assay exhibits the highest expanded Youden’s index, as well as the best overall diagnostic accuracy.
 Conclusions: None of evaluated screening tests can be recommended as individual method for the diagnosis of acute infection. We suppose that RT-PCR is unlikely to be a cost-effective screening strategy within the Serbian health system.
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Ivan Mangunsong, Albert, Sawkar Vijay Pramod, Ferry Safriadi, and Bethy S. Hernowo. "PREDICTION OF HYPOECHOIC LESIONS ON ULTRASOUND OF PROSTATE CANCER BASED ON PSA INTERVAL AND GLEASON GROUP." Indonesian Journal of Urology 28, no. 2 (2021): 129–34. http://dx.doi.org/10.32421/juri.v28i2.676.
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Objective: To evaluate hypoechoic lesion in transrectal ultrasonography of prostate (TRUS-P) predictive value on prostate cancer based on PSA Interval and Gleason Group. Material & Methods: An observational analytic study with a cross-sectional design take place from January 2015 to December 2018 analyzing patients who had undergone TRUS-P Biopsy at Hasan Sadikin Hospital. Patients are divided into several subgroups according to different PSA levels. A p-value < 0.05 was considered statistically significant. PPV, NPV, and Youden’s index were all indexes reflecting the performance of a diagnostic test. Results: There were 35 cases (49.3%) with a visible hypoechoic lesion in TRUS and 36 cases (41.7%) without a visible hypoechoic lesion. In our study, 23.9% of the patients with hypoechoic lesions were diagnosed with prostate cancer on TRUSP-Biopsy. The results of the analysis with Youden’s index show that PSA at intervals of 10-20 is the best predictor of diagnostic values. Then we analyzed the overall detection rate based on PSA interval. Patients with PSA > 20 ng/ml, hypoechoic lesions were significantly associated with Gleason Group. Conclusion: We concluded in our study that the hypoechoic lesion in transurethral ultrasonography of prostate could improve the predictive efficacy for diagnosing prostate cancer.
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Abrams, Gary A., Anna M. Rabil, Ana-Ysabel P. Williams, and Eric M. Hecht. "Serum Alanine Transaminase Is an Inadequate Nonalcoholic Fatty Liver Screening Test in Adolescents: Results From the National Health and Nutrition Examination Survey 2017-2018." Clinical Pediatrics 60, no. 8 (2021): 370–75. http://dx.doi.org/10.1177/00099228211020177.
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Nonalcoholic fatty liver disease (NAFLD) is common in overweight adolescents, and screening with serum alanine transaminase (ALT) levels is recommended by the American Academy of Pediatrics. We sought to determine if ALT is an accurate adolescent screening measure for NAFLD in a nationally representative sample of overweight adolescents. Diagnosis of NAFLD was determined using vibration-controlled transient elastography. Analyses were performed to calculate the sensitivity, specificity, positive predictive value, negative predictive value, and Youden’s index at various serum ALT cutoff levels. Receiver operating curves were generated in order to determine ALT’s discrimination capability. Males and females were analyzed separately. While average measures (mean and median) of ALT were higher in subjects with NAFLD, ALT provided only minimal discrimination with AUROC (area under the receiver operating characteristic) values of .66 in males and .67 in females. In a nationally representative sample of overweight and obese adolescents, serum ALT level functioned inadequately as a screening test to detect NAFLD.
Dissertations / Theses on the topic "Youden’s Test"
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Bastos, Carina de Almeida. "Desenvolvimento e validação de um método para a determinação simultânea de mesilato de nelfinavir e duas impurezas por cromatografia eletrocinética micelar (CEM)." Universidade Federal de Juiz de Fora (UFJF), 2015. https://repositorio.ufjf.br/jspui/handle/ufjf/4452.
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Previous issue date: 2015-03-20<br>CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>Um método cromatográfico eletrocinético micelar para a determinação simultânea do mesilato de nelfinavir e das impurezas ácido 3-hidroxi-2-metilbenzóico e benzoato de (2R,3R)-4-((3S,4aS,8aS)-3-(terc-butilcarbamoil)octahidroisoquinolina-2(1H)-il)-3-hidroxi-1-(feniltio)butano-2-amônio, com tempo de análise de 25 minutos, foi proposto. O eletrólito composto por tampão tetraborato de sódio (pH 9,24; 25 mmol L−1), dodecil sulfato de sódio (9 mmol L−1) e metanol (10%, v/v) foi otimizado utilizando planejamento fatorial misto, com detecção direta em 200 nm. Após avaliação das figuras de mérito seletividade, linearidade, precisão, limite de detecção, limite de quantificação, exatidão e robustez (Teste de Youden), o método foi aplicado na análise do mesilato de nelfinavir e suas impurezas em uma formulação farmacêutica (comprimidos). O método otimizado pode ser útil na determinação desses analitos em processos de monitoramento de síntese, matérias-primas e formulações farmacêuticas, oferecendo como vantagens baixo consumo de solventes, pequena demanda de amostra e uso de colunas não específicas.<br>A methodology for the simultaneous determination of nelfinavir mesylate and the impurities 3-hydroxy-2-methylbenzoic acid and (2R,3R)-4-((3S,4aS,8aS)-3-(tert-butylcarbamoyl) octahydroisoquinolin-2(1H)-yl)-3-hydroxy-1-(phenylthio)butan-2-aminium benzoate by micellar electrokinetic chromatography, with an analysis time of 25 min, was proposed. An electrolyte composed of sodium tetraborate buffer (pH 9.24; 25 mmol L−1), sodium dodecyl sulphate (9 mmol L−1) and methanol (10%, v/v) was optimized using a mixed-level factorial design, with direct detection at 200 nm. After evaluating some figures of merit, such as selectivity, linearity, precision, limit of detection, limit of quantification, accuracy and robustness (Youden’s test), the method was successfully applied to the analysis of nelfinavir mesylate and its impurities in a pharmaceutical formulation (tablets). The optimized methodology is demonstrated to be useful in the determination of these analytes in a synthesis monitoring process, in raw materials and in pharmaceutical formulations, while offering low solvent consumption, requiring a small sample and using non-specific columns as advantages.
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Zhou, Haochuan. "Statistical Inferences for the Youden Index." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/math_diss/5.
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In diagnostic test studies, one crucial task is to evaluate the diagnostic accuracy of a test. Currently, most studies focus on the Receiver Operating Characteristics Curve and the Area Under the Curve. On the other hand, the Youden index, widely applied in practice, is another comprehensive measurement for the performance of a diagnostic test. For a continuous-scale test classifying diseased and non-diseased groups, finding the Youden index of the test is equivalent to maximize the sum of sensitivity and specificity for all the possible values of the cut-point. This dissertation concentrates on statistical inferences for the Youden index. First, an auxiliary tool for the Youden index, called the diagnostic curve, is defined and used to evaluate the diagnostic test. Second, in the paired-design study to assess the diagnostic accuracy of two biomarkers, the difference in paired Youden indices frequently acts as an evaluation standard. We propose an exact confidence interval for the difference in paired Youden indices based on generalized pivotal quantities. A maximum likelihood estimate-based interval and a bootstrap-based interval are also included in the study. Third, for certain diseases, an intermediate level exists between diseased and non-diseased status. With such concern, we define the Youden index for three ordinal groups, propose the empirical estimate of the Youden index, study the asymptotic properties of the empirical Youden index estimate, and construct parametric and nonparametric confidence intervals for the Youden index. Finally, since covariates often affect the accuracy of a diagnostic test, therefore, we propose estimates for the Youden index with a covariate adjustment under heteroscedastic regression models for the test results. Asymptotic properties of the covariate-adjusted Youden index estimators are investigated under normal error and non-normal error assumptions.
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Wilk, Amber R. "The Estimation and Evaluation of Optimal Thresholds for Two Sequential Testing Strategies." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3163.
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Many continuous medical tests often rely on a threshold for diagnosis. There are two sequential testing strategies of interest: Believe the Positive (BP) and Believe the Negative (BN). BP classifies a patient positive if either the first test is greater than a threshold θ1 or negative on the first test and greater than θ2 on the second test. BN classifies a patient positive if the first test is greater than a threshold θ3 and greater than θ4 on the second test. Threshold pairs θ = (θ1, θ2) or (θ3, θ4), depending on strategy, are defined as optimal if they maximized GYI = Se + r(Sp – 1). Of interest is to determine if these optimal threshold, or optimal operating point (OOP), estimates are “good” when calculated from a sample. The methods proposed in this dissertation derive formulae to estimate θ assuming tests follow a binormal distribution, using the Newton-Raphson algorithm with ridging. A simulation study is performed assessing bias, root mean square error, percentage of over estimation of Se/Sp, and coverage of simultaneous confidence intervals and confidence regions for sets of population parameters and sample sizes. Additionally, OOPs are compared to the traditional empirical approach estimates. Bootstrapping is used to estimate the variance of each optimal threshold pair estimate. The study shows that parameters such as the area under the curve, ratio of standard deviations of disease classification groups within tests, correlation between tests within a disease classification, total sample size, and allocation of sample size to each disease classification group were all influential on OOP estimation. Additionally, the study shows that this method is an improvement over the empirical estimate. Equations for researchers to use in estimating total sample size and SCI width are also developed. Although the models did not produce high coefficients of determination, they are a good starting point for researchers when designing a study. A pancreatic cancer dataset is used to illustrate the OOP estimation methodology for sequential tests.
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Tabella, Gianluca. "Subsea Oil Spill Risk Management based on Sensor Networks." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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This thesis consists of the evaluation of sensor-based risk management against oil spills using an underwater distributed sensor network. The work starts by highlighting the importance of having a performing leak detection system both from an environmental, safety and economic point of view. The case study is the Goliat FPSO in the Barents Sea which has to meet requirements dictated by Norwegian authorities to prevent oil spills. The modeled network is made of passive acoustic sensors monitoring the subsea manifolds. These sensors send their local 1-bit decision to a Fusion Center which takes a global decision on whether the leakage is occurring. This work evaluates how the choice of adapted Fusion Rules (Counting Rule and Weighted Fusion Rule) can affect the performances of the leak detection system in its current geometry. It will also be discussed how different thresholds, selected for a specific FR or sensor test, can change the system performance. The detection methods are based on statistical signal processing adapted to fit this application within the Oil&Gas field. The work also proposes some new leak localization methods developed so they can be coupled with the proposed leak detection methods, giving a coherent set of operations that the sensors and the FC must perform. Performances of detection techniques are assessed balancing the need for high values of True Positive Rate and Precision and low values of False Positive Rate using indexes based both on the ROC curve (like the Youden's Index) and on the PR curve (the F-scores). Whereas, performances of localization techniques will be assessed on their ability to localize the spill in the shortest time; if this is not possible, parameters like the difference between the estimated and the real leak position will be considered. Finally, some tests are carried out applying the different sets of proposed methods.
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Li, Chenxue. "Generalized Confidence Intervals for Partial Youden Index and its Corresponding Optimal Cut-Off Point." 2013. http://scholarworks.gsu.edu/math_theses/133.
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In the field of diagnostic test studies, the accuracy of a diagnostic test is essential in evaluating the performance of the test. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) are widely used in such evaluation procedures. Meanwhile, the Youden index is also introduced into practice to measure the accuracy of the diagnostic test from another aspect. The Youden index maximizes the sum of sensitivity and specificity, assuring decent true positive and negative rates. It draws one's attention due to its merit of finding the optimal cut-off points of biomarkers. Similar to Partial ROC, a new index, called "Partial Youden index" can be defined as an extension of Youden's Index. It is more meaningful than regular Youden index since the regular one is just a special case of the Partial Youden Index. In this thesis, we focus on construction of generalized confidence intervals for the Partial Youden Index and its corresponding optimal cut-off points. Extensive simulation studies are conducted to evaluate the finite sample performances of the new intervals.
Conference papers on the topic "Youden’s Test"
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William, Darren Eduardo, Mitra Andini Sigilipoe, and Widya Christine Manus. "Comparison of Mini-Mental State Examination and Clock Drawing Test with Orientation-Memory-Concentration Test in the Elderly with Cognitive Function Impairment in Jetis Sub-District, Yogyakarta." In The 7th International Conference on Public Health 2020. Masters Program in Public Health, Universitas Sebelas Maret, 2020. http://dx.doi.org/10.26911/the7thicph.05.17.
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ABSTRACT Background: Dementia is a collective term for several diseases that affect memory, other cognitive abilities, and behavior. These diseases can seriously interfere with people’s ability of daily living. This is not a normal phenomenon of aging. With the increasing prevalence of dementia in the elderly, the importance of dementia as a comorbidity of hypertension is increasing. However, several questions regarding the link between hypertension and dementia remain unresolved. This study aimed to determine Orientation-Memory-Concentration-Test (OMCT) can be used to assess cognitive function in the elderly as an early step in the early detection of dementia. Subjects and Method: This was a comparative study using a case-control design. The study was conducted in Jetis Sub-District, Yogyakarta from September 2019 to June 2020. A total sample of 110 of elderly was divided into two groups 42 elderly (case), and 68 elderly (control) selected by consecutive sampling using the Mini-Mental State Examination (MMSE), Clock-Drawing Test (CDT) and Orientation-Memory-Concentration Test (OMCT). The dependent variables were the sensitivity and specificity level of the OMCT instrument while the scores of the MMSE. The independent variable was CDT instruments. The collected data will then be processed by diagnostic analysis followed by analysis of ROC and Youden’s index to determine the optimal cut off. Respondents are categorized as having impaired cognitive function if the MMSE (cut off ≤ 24) or CDT (cut off <18) shows a positive result. Results: 110 elderlies were involved. A total of 42 elderlies were included in the case population, and 68 elderlies were included in the control population. In the total OMCT population (cut off> 11) it has a sensitivity (29%) and specificity (97%) to the combination of MMSE and CDT. In populations with hypertension OMCT (cut off> 2.5) has sensitivity (68%) with specificity (46%). In a population without hypertension OMCT (cut off> 7) has a sensitivity (55%) and specificity (90%) to the combination of MMSE and CDT. Conclusion: OMCT can be used as a screening tool for cognitive dysfunction in older people with hypertension because of its short duration, ease of use, and can be used in patients with visual impairments. Keywords: Dementia, cognitive dysfunction, OMCT, 6-CIT. Correspondence: Darren Eduardo William. School of medicine Universitas Kristen Duta Wacana, Yogyakarta. Jl. Dr. Wahidin Sudirohusodo 5-25 Yogyakarta 55224, Indonesia. Email: Darreneduardowilliam@gmail.com. Mobile: 0813-4136-9999 DOI: https://doi.org/10.26911/the7thicph.05.17
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Mattingly, George E. "Establishing the International Acceptability of Fluid Quantity and Flow Rate Measurements (Invited Paper)." In ASME 2002 Joint U.S.-European Fluids Engineering Division Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/fedsm2002-31078.
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Rapid advances in technology-communications, the internet, tele-marketing, travel, etc. are accelerating the globalization of the world’s market places. To facilitate this globalization by eliminating measurement-based barriers to trade, the International Committee on Weights and Measures (CIPM) has, in accord with the authority granted it by the International Treaty of the Meter, produced a Mutual Recognition Arrangement (MRA). This MRA, signed into existence in Oct 1999, has the objectives: 1. to establish the degree of equivalence of national measurement standards maintained by the National Metrology Institutes (NMIs) that have signed the MRA, 2. to provide for the mutual recognition of calibration and measurement certificates issued by the NMIs, and thereby 3. to provide governments and other parties with a secure technical foundation for wider agreements regarding measurements that relate to international trade, commerce, and regulatory affairs. Information on the CIPM, and the MRA can be found on the website: http://www.bipm.org/. Degrees of equivalence between and among national measurement standards are based on the results of Key Comparisons (KCs) conducted within the Consultative Committees of the CIPM. Flow measurement efforts are being addressed by the newly formed Working Group for Fluid Flow (WGFF) of the CIPM Consultative Committee on Mass and Related Quantities (CCM). The WGFF efforts are organized into six, specific measurement areas: water, hydrocarbon liquid, air speed, liquid volume, high pressure gas, and low pressure gas flow. In each of these areas, and according to MRA rules, the efforts are to design and conduct KCs that quantify the equivalence of the flow standards maintained in the participating NMIs. To determine appropriate operating ranges for KC’s, the WGFF is reviewing the Calibration and Measurement Capabilities (CMCs) of the participating NMIs. This presentation will briefly describe the MRA and the current WGFF plans and programs to conduct the KC tests. Specific techniques planned for the KCs will be to design flow meter transfer standards comprised of tandem arrangements of flow meters that are tested in the selected fluid and flow conditions to quantify the performance of NMI flow standards under actual conditions of use. Statistically sufficient and metrologically sound test protocols are being devised to efficiently and effectively produce the required data bases. Youden graphical analysis of variance and other statistical techniques are planned to analyze the resulting data. The results of these WGFF efforts are expected to make it feasible for flow measurements made anywhere in the world to be understood and acceptable anywhere else.