Validation of biological activity testing procedure of recombinant human interleukin-7.

PubMed

Lutsenko, T N; Kovalenko, M V; Galkin, O Yu

2017-01-01

Validation procedure for method of monitoring the biological activity of reсombinant human interleukin-7 has been developed and conducted according to the requirements of national and international recommendations. This method is based on the ability of recombinant human interleukin-7 to induce proliferation of T lymphocytes. It has been shown that to control the biological activity of recombinant human interleukin-7 peripheral blood mononuclear cells (PBMCs) derived from blood or cell lines can be used. Validation charac­teristics that should be determined depend on the method, type of product or object test/measurement and biological test systems used in research. The validation procedure for the method of control of biological activity of recombinant human interleukin-7 in peripheral blood mononuclear cells showed satisfactory results on all parameters tested such as specificity, accuracy, precision and linearity.

A validated ultra high pressure liquid chromatographic method for qualification and quantification of folic acid in pharmaceutical preparations.

PubMed

Deconinck, E; Crevits, S; Baten, P; Courselle, P; De Beer, J

2011-04-05

A fully validated UHPLC method for the identification and quantification of folic acid in pharmaceutical preparations was developed. The starting conditions for the development were calculated starting from the HPLC conditions of a validated method. These start conditions were tested on four different UHPLC columns: Grace Vision HT™ C18-P, C18, C18-HL and C18-B (2 mm × 100 mm, 1.5 μm). After selection of the stationary phase, the method was further optimised by testing two aqueous and two organic phases and by adapting to a gradient method. The obtained method was fully validated based on its measurement uncertainty (accuracy profile) and robustness tests. A UHPLC method was obtained for the identification and quantification of folic acid in pharmaceutical preparations, which will cut analysis times and solvent consumption. Copyright © 2010 Elsevier B.V. All rights reserved.

Validation studies and proficiency testing.

PubMed

Ankilam, Elke; Heinze, Petra; Kay, Simon; Van den Eede, Guy; Popping, Bert

2002-01-01

Genetically modified organisms (GMOs) entered the European food market in 1996. Current legislation demands the labeling of food products if they contain <1% GMO, as assessed for each ingredient of the product. To create confidence in the testing methods and to complement enforcement requirements, there is an urgent need for internationally validated methods, which could serve as reference methods. To date, several methods have been submitted to validation trials at an international level; approaches now exist that can be used in different circumstances and for different food matrixes. Moreover, the requirement for the formal validation of methods is clearly accepted; several national and international bodies are active in organizing studies. Further validation studies, especially on the quantitative polymerase chain reaction methods, need to be performed to cover the rising demand for new extraction methods and other background matrixes, as well as for novel GMO constructs.

Development of a framework for international certification by OIE of diagnostic tests validated as fit for purpose.

PubMed

Wright, P; Edwards, S; Diallo, A; Jacobson, R

2006-01-01

Historically, the OIE has focused on test methods applicable to trade and the international movement of animals and animal products. With its expanding role as the World Organisation for Animal Health, the OIE has recognised the need to evaluate test methods relative to specific diagnostic applications other than trade. In collaboration with its international partners, the OIE solicited input from experts through consultants' meetings on the development of guidelines for validation and certification of diagnostic assays for infectious animal diseases. Recommendations from the first meeting were formally adopted and have subsequently been acted upon by the OIE. A validation template has been developed that specifically requires a test to be fit or suited for its intended purpose (e.g. as a screening or a confirmatory test). This is a key criterion for validation. The template incorporates four distinct stages of validation, each of which has bearing on the evaluation of fitness for purpose. The OIE has just recently created a registry for diagnostic tests that fulfil these validation requirements. Assay developers are invited to submit validation dossiers to the OIE for evaluation by a panel of experts. Recognising that validation is an incremental process, tests methods achieving at least the first stages of validation may be provisionally accepted. To provide additional confidence in assay performance, the OIE, through its network of Reference Laboratories, has embarked on the development of evaluation panels. These panels would contain specially selected test samples that would assist in verifying fitness for purpose.

Development of a framework for international certification by the OIE of diagnostic tests validated as fit for purpose.

PubMed

Wright, P; Edwards, S; Diallo, A; Jacobson, R

2007-01-01

Historically, the OIE has focussed on test methods applicable to trade and the international movement of animals and animal products. With its expanding role as the World Organisation for Animal Health, the OIE has recognised the need to evaluate test methods relative to specific diagnostic applications other than trade. In collaboration with its international partners, the OIE solicited input from experts through consultants meetings on the development of guidelines for validation and certification of diagnostic assays for infectious animal diseases. Recommendations from the first meeting were formally adopted and have subsequently been acted upon by the OIE. A validation template has been developed that specifically requires a test to be fit or suited for its intended purpose (e.g. as a screening or a confirmatory test). This is a key criterion for validation. The template incorporates four distinct stages of validation, each of which has bearing on the evaluation of fitness for purpose. The OIE has just recently created a registry for diagnostic tests that fulfil these validation requirements. Assay developers are invited to submit validation dossiers to the OIE for evaluation by a panel of experts. Recognising that validation is an incremental process, tests methods achieving at least the first stages of validation may be provisionally accepted. To provide additional confidence in assay performance, the OIE, through its network of Reference Laboratories, has embarked on the development of evaluation panels. These panels would contain specially selected test samples that would assist in verifying fitness for purpose.

A method for validation of finite element forming simulation on basis of a pointwise comparison of distance and curvature

NASA Astrophysics Data System (ADS)

Dörr, Dominik; Joppich, Tobias; Schirmaier, Fabian; Mosthaf, Tobias; Kärger, Luise; Henning, Frank

2016-10-01

Thermoforming of continuously fiber reinforced thermoplastics (CFRTP) is ideally suited to thin walled and complex shaped products. By means of forming simulation, an initial validation of the producibility of a specific geometry, an optimization of the forming process and the prediction of fiber-reorientation due to forming is possible. Nevertheless, applied methods need to be validated. Therefor a method is presented, which enables the calculation of error measures for the mismatch between simulation results and experimental tests, based on measurements with a conventional coordinate measuring device. As a quantitative measure, describing the curvature is provided, the presented method is also suitable for numerical or experimental sensitivity studies on wrinkling behavior. The applied methods for forming simulation, implemented in Abaqus explicit, are presented and applied to a generic geometry. The same geometry is tested experimentally and simulation and test results are compared by the proposed validation method.

Analytical difficulties facing today's regulatory laboratories: issues in method validation.

PubMed

MacNeil, James D

2012-08-01

The challenges facing analytical laboratories today are not unlike those faced in the past, although both the degree of complexity and the rate of change have increased. Challenges such as development and maintenance of expertise, maintenance and up-dating of equipment, and the introduction of new test methods have always been familiar themes for analytical laboratories, but international guidelines for laboratories involved in the import and export testing of food require management of such changes in a context which includes quality assurance, accreditation, and method validation considerations. Decisions as to when a change in a method requires re-validation of the method or on the design of a validation scheme for a complex multi-residue method require a well-considered strategy, based on a current knowledge of international guidance documents and regulatory requirements, as well the laboratory's quality system requirements. Validation demonstrates that a method is 'fit for purpose', so the requirement for validation should be assessed in terms of the intended use of a method and, in the case of change or modification of a method, whether that change or modification may affect a previously validated performance characteristic. In general, method validation involves method scope, calibration-related parameters, method precision, and recovery. Any method change which may affect method scope or any performance parameters will require re-validation. Some typical situations involving change in methods are discussed and a decision process proposed for selection of appropriate validation measures. © 2012 John Wiley & Sons, Ltd.

Improving the quality of discrete-choice experiments in health: how can we assess validity and reliability?

PubMed

Janssen, Ellen M; Marshall, Deborah A; Hauber, A Brett; Bridges, John F P

2017-12-01

The recent endorsement of discrete-choice experiments (DCEs) and other stated-preference methods by regulatory and health technology assessment (HTA) agencies has placed a greater focus on demonstrating the validity and reliability of preference results. Areas covered: We present a practical overview of tests of validity and reliability that have been applied in the health DCE literature and explore other study qualities of DCEs. From the published literature, we identify a variety of methods to assess the validity and reliability of DCEs. We conceptualize these methods to create a conceptual model with four domains: measurement validity, measurement reliability, choice validity, and choice reliability. Each domain consists of three categories that can be assessed using one to four procedures (for a total of 24 tests). We present how these tests have been applied in the literature and direct readers to applications of these tests in the health DCE literature. Based on a stakeholder engagement exercise, we consider the importance of study characteristics beyond traditional concepts of validity and reliability. Expert commentary: We discuss study design considerations to assess the validity and reliability of a DCE, consider limitations to the current application of tests, and discuss future work to consider the quality of DCEs in healthcare.

Utility of NIST Whole-Genome Reference Materials for the Technical Validation of a Multigene Next-Generation Sequencing Test.

PubMed

Shum, Bennett O V; Henner, Ilya; Belluoccio, Daniele; Hinchcliffe, Marcus J

2017-07-01

The sensitivity and specificity of next-generation sequencing laboratory developed tests (LDTs) are typically determined by an analyte-specific approach. Analyte-specific validations use disease-specific controls to assess an LDT's ability to detect known pathogenic variants. Alternatively, a methods-based approach can be used for LDT technical validations. Methods-focused validations do not use disease-specific controls but use benchmark reference DNA that contains known variants (benign, variants of unknown significance, and pathogenic) to assess variant calling accuracy of a next-generation sequencing workflow. Recently, four whole-genome reference materials (RMs) from the National Institute of Standards and Technology (NIST) were released to standardize methods-based validations of next-generation sequencing panels across laboratories. We provide a practical method for using NIST RMs to validate multigene panels. We analyzed the utility of RMs in validating a novel newborn screening test that targets 70 genes, called NEO1. Despite the NIST RM variant truth set originating from multiple sequencing platforms, replicates, and library types, we discovered a 5.2% false-negative variant detection rate in the RM truth set genes that were assessed in our validation. We developed a strategy using complementary non-RM controls to demonstrate 99.6% sensitivity of the NEO1 test in detecting variants. Our findings have implications for laboratories or proficiency testing organizations using whole-genome NIST RMs for testing. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Development of an Itemwise Efficiency Scoring Method: Concurrent, Convergent, Discriminant, and Neuroimaging-Based Predictive Validity Assessed in a Large Community Sample

PubMed Central

Moore, Tyler M.; Reise, Steven P.; Roalf, David R.; Satterthwaite, Theodore D.; Davatzikos, Christos; Bilker, Warren B.; Port, Allison M.; Jackson, Chad T.; Ruparel, Kosha; Savitt, Adam P.; Baron, Robert B.; Gur, Raquel E.; Gur, Ruben C.

2016-01-01

Traditional “paper-and-pencil” testing is imprecise in measuring speed and hence limited in assessing performance efficiency, but computerized testing permits precision in measuring itemwise response time. We present a method of scoring performance efficiency (combining information from accuracy and speed) at the item level. Using a community sample of 9,498 youths age 8-21, we calculated item-level efficiency scores on four neurocognitive tests, and compared the concurrent, convergent, discriminant, and predictive validity of these scores to simple averaging of standardized speed and accuracy-summed scores. Concurrent validity was measured by the scores' abilities to distinguish men from women and their correlations with age; convergent and discriminant validity were measured by correlations with other scores inside and outside of their neurocognitive domains; predictive validity was measured by correlations with brain volume in regions associated with the specific neurocognitive abilities. Results provide support for the ability of itemwise efficiency scoring to detect signals as strong as those detected by standard efficiency scoring methods. We find no evidence of superior validity of the itemwise scores over traditional scores, but point out several advantages of the former. The itemwise efficiency scoring method shows promise as an alternative to standard efficiency scoring methods, with overall moderate support from tests of four different types of validity. This method allows the use of existing item analysis methods and provides the convenient ability to adjust the overall emphasis of accuracy versus speed in the efficiency score, thus adjusting the scoring to the real-world demands the test is aiming to fulfill. PMID:26866796

Validating Test Score Meaning and Defending Test Score Use: Different Aims, Different Methods

ERIC Educational Resources Information Center

Cizek, Gregory J.

2016-01-01

Advances in validity theory and alacrity in validation practice have suffered because the term "validity" has been used to refer to two incompatible concerns: (1) the degree of support for specified interpretations of test scores (i.e. intended score meaning) and (2) the degree of support for specified applications (i.e. intended test…

ASTM Validates Air Pollution Test Methods

ERIC Educational Resources Information Center

Chemical and Engineering News, 1973

1973-01-01

The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

A Generalized Pivotal Quantity Approach to Analytical Method Validation Based on Total Error.

PubMed

Yang, Harry; Zhang, Jianchun

2015-01-01

The primary purpose of method validation is to demonstrate that the method is fit for its intended use. Traditionally, an analytical method is deemed valid if its performance characteristics such as accuracy and precision are shown to meet prespecified acceptance criteria. However, these acceptance criteria are not directly related to the method's intended purpose, which is usually a gurantee that a high percentage of the test results of future samples will be close to their true values. Alternate "fit for purpose" acceptance criteria based on the concept of total error have been increasingly used. Such criteria allow for assessing method validity, taking into account the relationship between accuracy and precision. Although several statistical test methods have been proposed in literature to test the "fit for purpose" hypothesis, the majority of the methods are not designed to protect the risk of accepting unsuitable methods, thus having the potential to cause uncontrolled consumer's risk. In this paper, we propose a test method based on generalized pivotal quantity inference. Through simulation studies, the performance of the method is compared to five existing approaches. The results show that both the new method and the method based on β-content tolerance interval with a confidence level of 90%, hereafter referred to as the β-content (0.9) method, control Type I error and thus consumer's risk, while the other existing methods do not. It is further demonstrated that the generalized pivotal quantity method is less conservative than the β-content (0.9) method when the analytical methods are biased, whereas it is more conservative when the analytical methods are unbiased. Therefore, selection of either the generalized pivotal quantity or β-content (0.9) method for an analytical method validation depends on the accuracy of the analytical method. It is also shown that the generalized pivotal quantity method has better asymptotic properties than all of the current methods. Analytical methods are often used to ensure safety, efficacy, and quality of medicinal products. According to government regulations and regulatory guidelines, these methods need to be validated through well-designed studies to minimize the risk of accepting unsuitable methods. This article describes a novel statistical test for analytical method validation, which provides better protection for the risk of accepting unsuitable analytical methods. © PDA, Inc. 2015.

77 FR 50510 - Federal Agency Responses to Interagency Coordinating Committee on the Validation of Alternative...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-21

... methods for potential use in the EPA EDSP. The evaluation indicated that no in vitro ER- or AR-based test... considered a high priority based on the lack of adequately validated test methods and the regulatory and... Limitations of the LUMI-CELL[supreg] ER (BG1Luc ER TA) Test Method, An In Vitro Assay for Identifying Human...

Validation of an Instrument to Measure High School Students' Attitudes toward Fitness Testing

ERIC Educational Resources Information Center

Mercier, Kevin; Silverman, Stephen

2014-01-01

Purpose: The purpose of this investigation was to develop an instrument that has scores that are valid and reliable for measuring students' attitudes toward fitness testing. Method: The method involved the following steps: (a) an elicitation study, (b) item development, (c) a pilot study, and (d) a validation study. The pilot study included 427…

Teaching Analytical Method Transfer through Developing and Validating Then Transferring Dissolution Testing Methods for Pharmaceuticals

ERIC Educational Resources Information Center

Kimaru, Irene; Koether, Marina; Chichester, Kimberly; Eaton, Lafayette

2017-01-01

Analytical method transfer (AMT) and dissolution testing are important topics required in industry that should be taught in analytical chemistry courses. Undergraduate students in senior level analytical chemistry laboratory courses at Kennesaw State University (KSU) and St. John Fisher College (SJFC) participated in development, validation, and…

Proposal of a method for the evaluation of inaccuracy of home sphygmomanometers.

PubMed

Akpolat, Tekin

2009-10-01

There is no formal protocol for evaluating the individual accuracy of home sphygmomanometers. The aims of this study were to propose a method for achieving accuracy in automated home sphygmomanometers and to test the applicability of the defined method. The purposes of this method were to avoid major inaccuracies and to estimate the optimal circumstance for individual accuracy. The method has three stages and sequential measurement of blood pressure is used. The tested devices were categorized into four groups: accurate, acceptable, inaccurate and very inaccurate (major inaccuracy). The defined method takes approximately 10 min (excluding relaxation time) and was tested on three different occasions. The application of the method has shown that inaccuracy is a common problem among non-tested devices, that validated devices are superior to those that are non-validated or whose validation status is unknown, that major inaccuracy is common, especially in non-tested devices and that validation does not guarantee individual accuracy. A protocol addressing the accuracy of a particular sphygmomanometer in an individual patient is required, and a practical method has been suggested to achieve this. This method can be modified, but the main idea and approach should be preserved unless a better method is proposed. The purchase of validated devices and evaluation of accuracy for the purchased device in an individual patient will improve the monitoring of self-measurement of blood pressure at home. This study addresses device inaccuracy, but errors related to the patient, observer or blood pressure measurement technique should not be underestimated, and strict adherence to the manufacturer's instructions is essential.

Designing the Nuclear Energy Attitude Scale.

ERIC Educational Resources Information Center

Calhoun, Lawrence; And Others

1988-01-01

Presents a refined method for designing a valid and reliable Likert-type scale to test attitudes toward the generation of electricity from nuclear energy. Discusses various tests of validity that were used on the nuclear energy scale. Reports results of administration and concludes that the test is both reliable and valid. (CW)

Assessment of a condition-specific quality-of-life measure for patients with developmentally absent teeth: validity and reliability testing.

PubMed

Akram, A J; Ireland, A J; Postlethwaite, K C; Sandy, J R; Jerreat, A S

2013-11-01

This article describes the process of validity and reliability testing of a condition-specific quality-of-life measure for patients with hypodontia presenting for orthodontic treatment. The development of the instrument is described in a previous article. Royal Devon and Exeter NHS Foundation Trust & Musgrove Park Hospital, Taunton. The child perception questionnaire was used as a standard against which to test criterion validity. The Bland and Altman method was used to check agreement between the two questionnaires. Construct validity was tested using principal component analysis on the four sections of the questionnaire. Test-retest reliability was tested using intraclass correlation coefficient and Bland and Altman method. Cronbach's alpha was used to test internal consistency reliability. Overall the questionnaire showed good reliability, criterion and construct validity. This together with previous evidence of good face and content validity suggests that the instrument may prove useful in clinical practice and further research. This study has demonstrated that the newly developed condition-specific quality-of-life questionnaire is both valid and reliable for use in young patients with hypodontia. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Contemporary Test Validity in Theory and Practice: A Primer for Discipline-Based Education Researchers

PubMed Central

Reeves, Todd D.; Marbach-Ad, Gili

2016-01-01

Most discipline-based education researchers (DBERs) were formally trained in the methods of scientific disciplines such as biology, chemistry, and physics, rather than social science disciplines such as psychology and education. As a result, DBERs may have never taken specific courses in the social science research methodology—either quantitative or qualitative—on which their scholarship often relies so heavily. One particular aspect of (quantitative) social science research that differs markedly from disciplines such as biology and chemistry is the instrumentation used to quantify phenomena. In response, this Research Methods essay offers a contemporary social science perspective on test validity and the validation process. The instructional piece explores the concepts of test validity, the validation process, validity evidence, and key threats to validity. The essay also includes an in-depth example of a validity argument and validation approach for a test of student argument analysis. In addition to DBERs, this essay should benefit practitioners (e.g., lab directors, faculty members) in the development, evaluation, and/or selection of instruments for their work assessing students or evaluating pedagogical innovations. PMID:26903498

76 FR 28781 - Independent Scientific Peer Review Panel Report: Evaluation of the Validation Status of an In...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-18

... 29-30, 2011, to evaluate the validation status of the LUMI-CELL[supreg] (BG1Luc ER TA) test method...: http://iccvam.niehs.nih.gov/docs/endo_docs/EDPRPRept2011.pdf or by contacting NICEATM (see ADDRESSES). The report contains (1) the Panel's evaluation of the validation status of the test method and (2) the...

[Selection of risk and diagnosis in diabetic polyneuropathy. Validation of method of new systems].

PubMed

Jurado, Jerónimo; Caula, Jacinto; Pou i Torelló, Josep Maria

2006-06-30

In a previous study we developed a specific algorithm, the polyneuropathy selection method (PSM) with 4 parameters (age, HDL-C, HbA1c, and retinopathy), to select patients at risk of diabetic polyneuropathy (DPN). We also developed a simplified method for DPN diagnosis: outpatient polyneuropathy diagnosis (OPD), with 4 variables (symptoms and 3 objective tests). To confirm the validity of conventional tests for DPN diagnosis; to validate the discriminatory power of the PSM and the diagnostic value of OPD by evaluating their relationship to electrodiagnosis studies and objective clinical neurological assessment; and to evaluate the correlation of DPN and pro-inflammatory status. Cross-sectional, crossed association for PSM validation. Paired samples for OPD validation. Primary care in 3 counties. Random sample of 75 subjects from the type-2 diabetes census for PSM evaluation. Thirty DPN patients and 30 non-DPN patients (from 2 DM2 sub-groups in our earlier study) for OPD evaluation. The gold standard for DPN diagnosis will be studied by means of a clinical neurological study (symptoms, physical examination, and sensitivity tests) and electrodiagnosis studies (sensitivity and motor EMG). Risks of neuropathy, macroangiopathy and pro-inflammatory status (PCR, TNF soluble fraction and total TGF-beta1) will be studied in every subject. Electrodiagnosis studies should confirm the validity of conventional tests for DPN diagnosis. PSM and OPD will be valid methods for selecting patients at risk and diagnosing DPN. There will be a significant relationship between DPN and pro-inflammatory tests.

SAS molecular tests Escherichia coli O157 detection kit. Performance tested method 031203.

PubMed

Bapanpally, Chandra; Montier, Laura; Khan, Shah; Kasra, Akif; Brunelle, Sharon L

2014-01-01

The SAS Molecular tests Escherichia coli O157 Detection method, a loop-mediated isothermal amplification method, performed as well as or better than the U.S. Department of Agriculture, Food Safety Inspection Service Microbiology Laboratory Guidebook and the U.S. Food and Drug Administration Bacteriological Analytical Manual reference methods for ground beef, beef trim, bagged mixed lettuce, and fresh spinach. Ground beef (30% fat, 25 g test portion) was validated for 7-8 h enrichment, leafy greens were validated in a 6-7 h enrichment, and ground beef (30% fat, 375 g composite test portion) and beef trim (375 g composite test portion) were validated in a 16-20 h enrichment. The method performance for meat and leafy green matrixes was also shown to be acceptable under conditions of co-enrichment with Salmonella. Thus, after a short co-enrichment step, ground beef, beef trim, lettuce, and spinach can be tested for both Salmonella and E. coli O157. The SAS Molecular tests Salmonella Detection Kit was validated using the same test portions as for the SAS Molecular tests E. coli O157 Detection Kit and those results are presented in a separate report. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 50 E. coli 0157 strains, including H7 and non-motile strains, and 30 non-E. coli O157 strains examined. Finally, the method was shown to be robust when variations to DNA extract hold time and DNA volume were varied. The method comparison and robustness data suggest a full 7 h enrichment time should be used for 25 g ground beef test portions.

Bridging the Gap Between Validation and Implementation of Non-Animal Veterinary Vaccine Potency Testing Methods.

PubMed

Dozier, Samantha; Brown, Jeffrey; Currie, Alistair

2011-11-29

In recent years, technologically advanced high-throughput techniques have been developed that replace, reduce or refine animal use in vaccine quality control tests. Following validation, these tests are slowly being accepted for use by international regulatory authorities. Because regulatory acceptance itself has not guaranteed that approved humane methods are adopted by manufacturers, various organizations have sought to foster the preferential use of validated non-animal methods by interfacing with industry and regulatory authorities. After noticing this gap between regulation and uptake by industry, we began developing a paradigm that seeks to narrow the gap and quicken implementation of new replacement, refinement or reduction guidance. A systematic analysis of our experience in promoting the transparent implementation of validated non-animal vaccine potency assays has led to the refinement of our paradigmatic process, presented here, by which interested parties can assess the local regulatory acceptance of methods that reduce animal use and integrate them into quality control testing protocols, or ensure the elimination of peripheral barriers to their use, particularly for potency and other tests carried out on production batches.

Reliability and Validity of Information about Student Achievement: Comparing Large-Scale and Classroom Testing Contexts

ERIC Educational Resources Information Center

Cizek, Gregory J.

2009-01-01

Reliability and validity are two characteristics that must be considered whenever information about student achievement is collected. However, those characteristics--and the methods for evaluating them--differ in large-scale testing and classroom testing contexts. This article presents the distinctions between reliability and validity in the two…

International Harmonization and Cooperation in the Validation of Alternative Methods.

PubMed

Barroso, João; Ahn, Il Young; Caldeira, Cristiane; Carmichael, Paul L; Casey, Warren; Coecke, Sandra; Curren, Rodger; Desprez, Bertrand; Eskes, Chantra; Griesinger, Claudius; Guo, Jiabin; Hill, Erin; Roi, Annett Janusch; Kojima, Hajime; Li, Jin; Lim, Chae Hyung; Moura, Wlamir; Nishikawa, Akiyoshi; Park, HyeKyung; Peng, Shuangqing; Presgrave, Octavio; Singer, Tim; Sohn, Soo Jung; Westmoreland, Carl; Whelan, Maurice; Yang, Xingfen; Yang, Ying; Zuang, Valérie

The development and validation of scientific alternatives to animal testing is important not only from an ethical perspective (implementation of 3Rs), but also to improve safety assessment decision making with the use of mechanistic information of higher relevance to humans. To be effective in these efforts, it is however imperative that validation centres, industry, regulatory bodies, academia and other interested parties ensure a strong international cooperation, cross-sector collaboration and intense communication in the design, execution, and peer review of validation studies. Such an approach is critical to achieve harmonized and more transparent approaches to method validation, peer-review and recommendation, which will ultimately expedite the international acceptance of valid alternative methods or strategies by regulatory authorities and their implementation and use by stakeholders. It also allows achieving greater efficiency and effectiveness by avoiding duplication of effort and leveraging limited resources. In view of achieving these goals, the International Cooperation on Alternative Test Methods (ICATM) was established in 2009 by validation centres from Europe, USA, Canada and Japan. ICATM was later joined by Korea in 2011 and currently also counts with Brazil and China as observers. This chapter describes the existing differences across world regions and major efforts carried out for achieving consistent international cooperation and harmonization in the validation and adoption of alternative approaches to animal testing.

Practical Aspects of Designing and Conducting Validation Studies Involving Multi-study Trials.

PubMed

Coecke, Sandra; Bernasconi, Camilla; Bowe, Gerard; Bostroem, Ann-Charlotte; Burton, Julien; Cole, Thomas; Fortaner, Salvador; Gouliarmou, Varvara; Gray, Andrew; Griesinger, Claudius; Louhimies, Susanna; Gyves, Emilio Mendoza-de; Joossens, Elisabeth; Prinz, Maurits-Jan; Milcamps, Anne; Parissis, Nicholaos; Wilk-Zasadna, Iwona; Barroso, João; Desprez, Bertrand; Langezaal, Ingrid; Liska, Roman; Morath, Siegfried; Reina, Vittorio; Zorzoli, Chiara; Zuang, Valérie

This chapter focuses on practical aspects of conducting prospective in vitro validation studies, and in particular, by laboratories that are members of the European Union Network of Laboratories for the Validation of Alternative Methods (EU-NETVAL) that is coordinated by the EU Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM). Prospective validation studies involving EU-NETVAL, comprising a multi-study trial involving several laboratories or "test facilities", typically consist of two main steps: (1) the design of the validation study by EURL ECVAM and (2) the execution of the multi-study trial by a number of qualified laboratories within EU-NETVAL, coordinated and supported by EURL ECVAM. The approach adopted in the conduct of these validation studies adheres to the principles described in the OECD Guidance Document on the Validation and International Acceptance of new or updated test methods for Hazard Assessment No. 34 (OECD 2005). The context and scope of conducting prospective in vitro validation studies is dealt with in Chap. 4 . Here we focus mainly on the processes followed to carry out a prospective validation of in vitro methods involving different laboratories with the ultimate aim of generating a dataset that can support a decision in relation to the possible development of an international test guideline (e.g. by the OECD) or the establishment of performance standards.

Validity and reliability of bioelectrical impedance analysis and skinfold thickness in predicting body fat in military personnel.

PubMed

Aandstad, Anders; Holtberget, Kristian; Hageberg, Rune; Holme, Ingar; Anderssen, Sigmund A

2014-02-01

Previous studies show that body composition is related to injury risk and physical performance in soldiers. Thus, valid methods for measuring body composition in military personnel are needed. The frequently used body mass index method is not a valid measure of body composition in soldiers, but reliability and validity of alternative field methods are less investigated in military personnel. Thus, we carried out test and retest of skinfold (SKF), single frequency bioelectrical impedance analysis (SF-BIA), and multifrequency bioelectrical impedance analysis measurements in 65 male and female soldiers. Several validated equations were used to predict percent body fat from these methods. Dual-energy X-ray absorptiometry was also measured, and acted as the criterion method. Results showed that SF-BIA was the most reliable method in both genders. In women, SF-BIA was also the most valid method, whereas SKF or a combination of SKF and SF-BIA produced the highest validity in men. Reliability and validity varied substantially among the equations examined. The best methods and equations produced test-retest 95% limits of agreement below ±1% points, whereas the corresponding validity figures were ±3.5% points. Each investigator and practitioner must consider whether such measurement errors are acceptable for its specific use. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

A Model-Based Method for Content Validation of Automatically Generated Test Items

ERIC Educational Resources Information Center

Zhang, Xinxin; Gierl, Mark

2016-01-01

The purpose of this study is to describe a methodology to recover the item model used to generate multiple-choice test items with a novel graph theory approach. Beginning with the generated test items and working backward to recover the original item model provides a model-based method for validating the content used to automatically generate test…

Concept Development for Future Domains: A New Method of Knowledge Elicitation

DTIC Science & Technology

2005-06-01

Procedure: U.S. Army Research Institute for the Behavioral and Social Sciences (ARI) examined methods to generate, refine, test , and validate new...generate, elaborate, refine, describe, test , and validate new Future Force concepts relating to doctrine, tactics, techniques, procedures, unit and team...System (Harvey, 1993), and the Job Element Method (Primoff & Eyde , 1988). Figure 1 provides a more comprehensive list of task analytic methods. Please see

Experimental design methodologies in the optimization of chiral CE or CEC separations: an overview.

PubMed

Dejaegher, Bieke; Mangelings, Debby; Vander Heyden, Yvan

2013-01-01

In this chapter, an overview of experimental designs to develop chiral capillary electrophoresis (CE) and capillary electrochromatographic (CEC) methods is presented. Method development is generally divided into technique selection, method optimization, and method validation. In the method optimization part, often two phases can be distinguished, i.e., a screening and an optimization phase. In method validation, the method is evaluated on its fit for purpose. A validation item, also applying experimental designs, is robustness testing. In the screening phase and in robustness testing, screening designs are applied. During the optimization phase, response surface designs are used. The different design types and their application steps are discussed in this chapter and illustrated by examples of chiral CE and CEC methods.

JaCVAM-organized international validation study of the in vivo rodent alkaline comet assay for the detection of genotoxic carcinogens: I. Summary of pre-validation study results.

PubMed

Uno, Yoshifumi; Kojima, Hajime; Omori, Takashi; Corvi, Raffaella; Honma, Masamistu; Schechtman, Leonard M; Tice, Raymond R; Burlinson, Brian; Escobar, Patricia A; Kraynak, Andrew R; Nakagawa, Yuzuki; Nakajima, Madoka; Pant, Kamala; Asano, Norihide; Lovell, David; Morita, Takeshi; Ohno, Yasuo; Hayashi, Makoto

2015-07-01

The in vivo rodent alkaline comet assay (comet assay) is used internationally to investigate the in vivo genotoxic potential of test chemicals. This assay, however, has not previously been formally validated. The Japanese Center for the Validation of Alternative Methods (JaCVAM), with the cooperation of the U.S. NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM)/the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), the European Centre for the Validation of Alternative Methods (ECVAM), and the Japanese Environmental Mutagen Society/Mammalian Mutagenesis Study Group (JEMS/MMS), organized an international validation study to evaluate the reliability and relevance of the assay for identifying genotoxic carcinogens, using liver and stomach as target organs. The ultimate goal of this validation effort was to establish an Organisation for Economic Co-operation and Development (OECD) test guideline. The purpose of the pre-validation studies (i.e., Phase 1 through 3), conducted in four or five laboratories with extensive comet assay experience, was to optimize the protocol to be used during the definitive validation study. Copyright © 2015 Elsevier B.V. All rights reserved.

Directed Design of Experiments for Validating Probability of Detection Capability of a Testing System

NASA Technical Reports Server (NTRS)

Generazio, Edward R. (Inventor)

2012-01-01

A method of validating a probability of detection (POD) testing system using directed design of experiments (DOE) includes recording an input data set of observed hit and miss or analog data for sample components as a function of size of a flaw in the components. The method also includes processing the input data set to generate an output data set having an optimal class width, assigning a case number to the output data set, and generating validation instructions based on the assigned case number. An apparatus includes a host machine for receiving the input data set from the testing system and an algorithm for executing DOE to validate the test system. The algorithm applies DOE to the input data set to determine a data set having an optimal class width, assigns a case number to that data set, and generates validation instructions based on the case number.

Evidence-Based Toxicology.

PubMed

Hoffmann, Sebastian; Hartung, Thomas; Stephens, Martin

Evidence-based toxicology (EBT) was introduced independently by two groups in 2005, in the context of toxicological risk assessment and causation as well as based on parallels between the evaluation of test methods in toxicology and evidence-based assessment of diagnostics tests in medicine. The role model of evidence-based medicine (EBM) motivated both proposals and guided the evolution of EBT, whereas especially systematic reviews and evidence quality assessment attract considerable attention in toxicology.Regarding test assessment, in the search of solutions for various problems related to validation, such as the imperfectness of the reference standard or the challenge to comprehensively evaluate tests, the field of Diagnostic Test Assessment (DTA) was identified as a potential resource. DTA being an EBM discipline, test method assessment/validation therefore became one of the main drivers spurring the development of EBT.In the context of pathway-based toxicology, EBT approaches, given their objectivity, transparency and consistency, have been proposed to be used for carrying out a (retrospective) mechanistic validation.In summary, implementation of more evidence-based approaches may provide the tools necessary to adapt the assessment/validation of toxicological test methods and testing strategies to face the challenges of toxicology in the twenty first century.

An entropy-based nonparametric test for the validation of surrogate endpoints.

PubMed

Miao, Xiaopeng; Wang, Yong-Cheng; Gangopadhyay, Ashis

2012-06-30

We present a nonparametric test to validate surrogate endpoints based on measure of divergence and random permutation. This test is a proposal to directly verify the Prentice statistical definition of surrogacy. The test does not impose distributional assumptions on the endpoints, and it is robust to model misspecification. Our simulation study shows that the proposed nonparametric test outperforms the practical test of the Prentice criterion in terms of both robustness of size and power. We also evaluate the performance of three leading methods that attempt to quantify the effect of surrogate endpoints. The proposed method is applied to validate magnetic resonance imaging lesions as the surrogate endpoint for clinical relapses in a multiple sclerosis trial. Copyright © 2012 John Wiley & Sons, Ltd.

Development and validation of a discriminating in vitro dissolution method for a poorly soluble drug, olmesartan medoxomil: comparison between commercial tablets.

PubMed

Bajerski, Lisiane; Rossi, Rochele Cassanta; Dias, Carolina Lupi; Bergold, Ana Maria; Fröehlich, Pedro Eduardo

2010-06-01

A dissolution test for tablets containing 40 mg of olmesartan medoxomil (OLM) was developed and validated using both LC-UV and UV methods. After evaluation of the sink condition, dissolution medium, and stability of the drug, the method was validated using USP apparatus 2, 50 rpm rotation speed, and 900 ml of deaerated H(2)O + 0.5% sodium lauryl sulfate (w/v) at pH 6.8 (adjusted with 18% phosphoric acid) as the dissolution medium. The model-independent method using difference factor (f(1)) and similarity factor (f(2)), model-dependent method, and dissolution efficiency were employed to compare dissolution profiles. The kinetic parameters of drug release were also investigated. The obtained results provided adequate dissolution profiles. The developed dissolution test was validated according to international guidelines. Since there is no monograph for this drug in tablets, the dissolution method presented here can be used as a quality control test for OLM in this dosage form, especially in a batch to batch evaluation.

Developing a Research Method for Testing New Curriculum Ideas: Report No. 1 on Using Marketing Research in a Lifelong Learning Organization.

ERIC Educational Resources Information Center

Haskins, Jack B.

A survey method was developed and used to determine interest in new course topics at the Learning Institute for Elders (LIFE) at the University of Central Florida. In the absence of a known validated method for course concept testing, this approach was modeled after the "message pretesting," or formative, research used and validated in…

Verification and Validation Studies for the LAVA CFD Solver

NASA Technical Reports Server (NTRS)

Moini-Yekta, Shayan; Barad, Michael F; Sozer, Emre; Brehm, Christoph; Housman, Jeffrey A.; Kiris, Cetin C.

2013-01-01

The verification and validation of the Launch Ascent and Vehicle Aerodynamics (LAVA) computational fluid dynamics (CFD) solver is presented. A modern strategy for verification and validation is described incorporating verification tests, validation benchmarks, continuous integration and version control methods for automated testing in a collaborative development environment. The purpose of the approach is to integrate the verification and validation process into the development of the solver and improve productivity. This paper uses the Method of Manufactured Solutions (MMS) for the verification of 2D Euler equations, 3D Navier-Stokes equations as well as turbulence models. A method for systematic refinement of unstructured grids is also presented. Verification using inviscid vortex propagation and flow over a flat plate is highlighted. Simulation results using laminar and turbulent flow past a NACA 0012 airfoil and ONERA M6 wing are validated against experimental and numerical data.

Comparative study between EDXRF and ASTM E572 methods using two-way ANOVA

NASA Astrophysics Data System (ADS)

Krummenauer, A.; Veit, H. M.; Zoppas-Ferreira, J.

2018-03-01

Comparison with reference method is one of the necessary requirements for the validation of non-standard methods. This comparison was made using the experiment planning technique with two-way ANOVA. In ANOVA, the results obtained using the EDXRF method, to be validated, were compared with the results obtained using the ASTM E572-13 standard test method. Fisher's tests (F-test) were used to comparative study between of the elements: molybdenum, niobium, copper, nickel, manganese, chromium and vanadium. All F-tests of the elements indicate that the null hypothesis (Ho) has not been rejected. As a result, there is no significant difference between the methods compared. Therefore, according to this study, it is concluded that the EDXRF method was approved in this method comparison requirement.

Development and validation of a discriminative dissolution method for atorvastatin calcium tablets using in vivo data by LC and UV methods.

PubMed

Machado, J C; Lange, A D; Todeschini, V; Volpato, N M

2014-02-01

A dissolution method to analyze atorvastatin tablets using in vivo data for RP and test pilot (PB) was developed and validated. The appropriate conditions were determined after solubility tests using different media, and sink conditions were established. The conditions used were equipment paddle at 50 rpm and 900 mL of potassium phosphate buffer pH 6.0 as dissolution medium. In vivo release profiles were obtained from the bioequivalence study of RP and the generic candidate PB. The fraction of dose absorbed was calculated using the Loo-Riegelman method. It was necessary to use a scale factor of time similar to 6.0, to associate the values of absorbed fraction and dissolved fraction, obtaining an in vivo-in vitro correlation level A. The dissolution method to quantify the amount of drug dissolved was validated using high-performance liquid chromatography and ultraviolet spectrophotometry, and validated according to the USP protocol. The discriminative power of dissolution conditions was assessed using two different pilot batches of atorvastatin tablets (PA and PB) and RP. The dissolution test was validated and may be used as a discriminating method in quality control and in the development of the new formulations.

Content validity and reliability of test of gross motor development in Chilean children

PubMed Central

Cano-Cappellacci, Marcelo; Leyton, Fernanda Aleitte; Carreño, Joshua Durán

2016-01-01

ABSTRACT OBJECTIVE To validate a Spanish version of the Test of Gross Motor Development (TGMD-2) for the Chilean population. METHODS Descriptive, transversal, non-experimental validity and reliability study. Four translators, three experts and 92 Chilean children, from five to 10 years, students from a primary school in Santiago, Chile, have participated. The Committee of Experts has carried out translation, back-translation and revision processes to determine the translinguistic equivalence and content validity of the test, using the content validity index in 2013. In addition, a pilot implementation was achieved to determine test reliability in Spanish, by using the intraclass correlation coefficient and Bland-Altman method. We evaluated whether the results presented significant differences by replacing the bat with a racket, using T-test. RESULTS We obtained a content validity index higher than 0.80 for language clarity and relevance of the TGMD-2 for children. There were significant differences in the object control subtest when comparing the results with bat and racket. The intraclass correlation coefficient for reliability inter-rater, intra-rater and test-retest reliability was greater than 0.80 in all cases. CONCLUSIONS The TGMD-2 has appropriate content validity to be applied in the Chilean population. The reliability of this test is within the appropriate parameters and its use could be recommended in this population after the establishment of normative data, setting a further precedent for the validation in other Latin American countries. PMID:26815160

A practical method to test the validity of the standard Gumbel distribution in logit-based multinomial choice models of travel behavior

DOE PAGES

Ye, Xin; Garikapati, Venu M.; You, Daehyun; ...

2017-11-08

Most multinomial choice models (e.g., the multinomial logit model) adopted in practice assume an extreme-value Gumbel distribution for the random components (error terms) of utility functions. This distributional assumption offers a closed-form likelihood expression when the utility maximization principle is applied to model choice behaviors. As a result, model coefficients can be easily estimated using the standard maximum likelihood estimation method. However, maximum likelihood estimators are consistent and efficient only if distributional assumptions on the random error terms are valid. It is therefore critical to test the validity of underlying distributional assumptions on the error terms that form the basismore » of parameter estimation and policy evaluation. In this paper, a practical yet statistically rigorous method is proposed to test the validity of the distributional assumption on the random components of utility functions in both the multinomial logit (MNL) model and multiple discrete-continuous extreme value (MDCEV) model. Based on a semi-nonparametric approach, a closed-form likelihood function that nests the MNL or MDCEV model being tested is derived. The proposed method allows traditional likelihood ratio tests to be used to test violations of the standard Gumbel distribution assumption. Simulation experiments are conducted to demonstrate that the proposed test yields acceptable Type-I and Type-II error probabilities at commonly available sample sizes. The test is then applied to three real-world discrete and discrete-continuous choice models. For all three models, the proposed test rejects the validity of the standard Gumbel distribution in most utility functions, calling for the development of robust choice models that overcome adverse effects of violations of distributional assumptions on the error terms in random utility functions.« less

A practical method to test the validity of the standard Gumbel distribution in logit-based multinomial choice models of travel behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Xin; Garikapati, Venu M.; You, Daehyun

Most multinomial choice models (e.g., the multinomial logit model) adopted in practice assume an extreme-value Gumbel distribution for the random components (error terms) of utility functions. This distributional assumption offers a closed-form likelihood expression when the utility maximization principle is applied to model choice behaviors. As a result, model coefficients can be easily estimated using the standard maximum likelihood estimation method. However, maximum likelihood estimators are consistent and efficient only if distributional assumptions on the random error terms are valid. It is therefore critical to test the validity of underlying distributional assumptions on the error terms that form the basismore » of parameter estimation and policy evaluation. In this paper, a practical yet statistically rigorous method is proposed to test the validity of the distributional assumption on the random components of utility functions in both the multinomial logit (MNL) model and multiple discrete-continuous extreme value (MDCEV) model. Based on a semi-nonparametric approach, a closed-form likelihood function that nests the MNL or MDCEV model being tested is derived. The proposed method allows traditional likelihood ratio tests to be used to test violations of the standard Gumbel distribution assumption. Simulation experiments are conducted to demonstrate that the proposed test yields acceptable Type-I and Type-II error probabilities at commonly available sample sizes. The test is then applied to three real-world discrete and discrete-continuous choice models. For all three models, the proposed test rejects the validity of the standard Gumbel distribution in most utility functions, calling for the development of robust choice models that overcome adverse effects of violations of distributional assumptions on the error terms in random utility functions.« less

Performance Validity Testing in Neuropsychology: Methods for Measurement Development and Maximizing Diagnostic Accuracy.

PubMed

Wodushek, Thomas R; Greher, Michael R

2017-05-01

In the first column in this 2-part series, Performance Validity Testing in Neuropsychology: Scientific Basis and Clinical Application-A Brief Review, the authors introduced performance validity tests (PVTs) and their function, provided a justification for why they are necessary, traced their ongoing endorsement by neuropsychological organizations, and described how they are used and interpreted by ever increasing numbers of clinical neuropsychologists. To enhance readers' understanding of these measures, this second column briefly describes common detection strategies used in PVTs as well as the typical methods used to validate new PVTs and determine cut scores for valid/invalid determinations. We provide a discussion of the latest research demonstrating how neuropsychologists can combine multiple PVTs in a single battery to improve sensitivity/specificity to invalid responding. Finally, we discuss future directions for the research and application of PVTs.

Development of a refractive error quality of life scale for Thai adults (the REQ-Thai).

PubMed

Sukhawarn, Roongthip; Wiratchai, Nonglak; Tatsanavivat, Pyatat; Pitiyanuwat, Somwung; Kanato, Manop; Srivannaboon, Sabong; Guyatt, Gordon H

2011-08-01

To develop a scale for measuring refractive error quality of life (QOL) for Thai adults. The full survey comprised 424 respondents from 5 medical centers in Bangkok and from 3 medical centers in Chiangmai, Songkla and KhonKaen provinces. Participants were emmetropes and persons with refractive correction with visual acuity of 20/30 or better An item reduction process was employed by combining 3 methods-expert opinion, impact method and item-total correlation methods. The classical reliability testing and the validity testing including convergent, discriminative and construct validity was performed. The developed questionnaire comprised 87 items in 6 dimensions: 1) quality of vision, 2) visual function, 3) social function, 4) psychological function, 5) symptoms and 6) refractive correction problems. It is the 5-level Likert scale type. The Cronbach's Alpha coefficients of its dimensions ranged from 0.756 to 0. 979. All validity testing were shown to be valid. The construct validity was validated by the confirmatory factor analysis. A short version questionnaire comprised 48 items with good reliability and validity was also developed. This is the first validated instrument for measuring refractive error quality of life for Thai adults that was developed with strong research methodology and large sample size.

An exploratory study into the effect of time-restricted internet access on face-validity, construct validity and reliability of postgraduate knowledge progress testing

PubMed Central

2013-01-01

Background Yearly formative knowledge testing (also known as progress testing) was shown to have a limited construct-validity and reliability in postgraduate medical education. One way to improve construct-validity and reliability is to improve the authenticity of a test. As easily accessible internet has become inseparably linked to daily clinical practice, we hypothesized that allowing internet access for a limited amount of time during the progress test would improve the perception of authenticity (face-validity) of the test, which would in turn improve the construct-validity and reliability of postgraduate progress testing. Methods Postgraduate trainees taking the yearly knowledge progress test were asked to participate in a study where they could access the internet for 30 minutes at the end of a traditional pen and paper test. Before and after the test they were asked to complete a short questionnaire regarding the face-validity of the test. Results Mean test scores increased significantly for all training years. Trainees indicated that the face-validity of the test improved with internet access and that they would like to continue to have internet access during future testing. Internet access did not improve the construct-validity or reliability of the test. Conclusion Improving the face-validity of postgraduate progress testing, by adding the possibility to search the internet for a limited amount of time, positively influences test performance and face-validity. However, it did not change the reliability or the construct-validity of the test. PMID:24195696

Psychological testing and psychological assessment. A review of evidence and issues.

PubMed

Meyer, G J; Finn, S E; Eyde, L D; Kay, G G; Moreland, K L; Dies, R R; Eisman, E J; Kubiszyn, T W; Reed, G M

2001-02-01

This article summarizes evidence and issues associated with psychological assessment. Data from more than 125 meta-analyses on test validity and 800 samples examining multimethod assessment suggest 4 general conclusions: (a) Psychological test validity is strong and compelling, (b) psychological test validity is comparable to medical test validity, (c) distinct assessment methods provide unique sources of information, and (d) clinicians who rely exclusively on interviews are prone to incomplete understandings. Following principles for optimal nomothetic research, the authors suggest that a multimethod assessment battery provides a structured means for skilled clinicians to maximize the validity of individualized assessments. Future investigations should move beyond an examination of test scales to focus more on the role of psychologists who use tests as helpful tools to furnish patients and referral sources with professional consultation.

RELAP-7 Software Verification and Validation Plan: Requirements Traceability Matrix (RTM) Part 1 – Physics and numerical methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Yong Joon; Yoo, Jun Soo; Smith, Curtis Lee

2015-09-01

This INL plan comprehensively describes the Requirements Traceability Matrix (RTM) on main physics and numerical method of the RELAP-7. The plan also describes the testing-based software verification and validation (SV&V) process—a set of specially designed software models used to test RELAP-7.

Sterilization validation for medical devices at IRASM microbiological laboratory—Practical approaches

NASA Astrophysics Data System (ADS)

Trandafir, Laura; Alexandru, Mioara; Constantin, Mihai; Ioniţă, Anca; Zorilă, Florina; Moise, Valentin

2012-09-01

EN ISO 11137 established regulations for setting or substantiating the dose for achieving the desired sterility assurance level. The validation studies can be designed in particular for different types of products. Each product needs distinct protocols for bioburden determination and sterility testing. The Microbiological Laboratory from Irradiation Processing Center (IRASM) deals with different types of products, mainly for the VDmax25 method. When it comes to microbiological evaluation the most challenging was cotton gauze. A special situation for establishing the sterilization validation method appears in cases of cotton packed in large quantities. The VDmax25 method cannot be applied for items with average bioburden more than 1000 CFU/pack, irrespective of the weight of the package. This is a method limitation and implies increased costs for the manufacturer when choosing other methods. For microbiological tests, culture condition should be selected in both cases of the bioburden and sterility testing. Details about choosing criteria are given.

Evaluation of Criterion Validity for Scales with Congeneric Measures

ERIC Educational Resources Information Center

Raykov, Tenko

2007-01-01

A method for estimating criterion validity of scales with homogeneous components is outlined. It accomplishes point and interval estimation of interrelationship indices between composite scores and criterion variables and is useful for testing hypotheses about criterion validity of measurement instruments. The method can also be used with missing…

Survey of Verification and Validation Techniques for Small Satellite Software Development

NASA Technical Reports Server (NTRS)

Jacklin, Stephen A.

2015-01-01

The purpose of this paper is to provide an overview of the current trends and practices in small-satellite software verification and validation. This document is not intended to promote a specific software assurance method. Rather, it seeks to present an unbiased survey of software assurance methods used to verify and validate small satellite software and to make mention of the benefits and value of each approach. These methods include simulation and testing, verification and validation with model-based design, formal methods, and fault-tolerant software design with run-time monitoring. Although the literature reveals that simulation and testing has by far the longest legacy, model-based design methods are proving to be useful for software verification and validation. Some work in formal methods, though not widely used for any satellites, may offer new ways to improve small satellite software verification and validation. These methods need to be further advanced to deal with the state explosion problem and to make them more usable by small-satellite software engineers to be regularly applied to software verification. Last, it is explained how run-time monitoring, combined with fault-tolerant software design methods, provides an important means to detect and correct software errors that escape the verification process or those errors that are produced after launch through the effects of ionizing radiation.

Evolving the Principles and Practice of Validation for New Alternative Approaches to Toxicity Testing.

PubMed

Whelan, Maurice; Eskes, Chantra

Validation is essential for the translation of newly developed alternative approaches to animal testing into tools and solutions suitable for regulatory applications. Formal approaches to validation have emerged over the past 20 years or so and although they have helped greatly to progress the field, it is essential that the principles and practice underpinning validation continue to evolve to keep pace with scientific progress. The modular approach to validation should be exploited to encourage more innovation and flexibility in study design and to increase efficiency in filling data gaps. With the focus now on integrated approaches to testing and assessment that are based on toxicological knowledge captured as adverse outcome pathways, and which incorporate the latest in vitro and computational methods, validation needs to adapt to ensure it adds value rather than hinders progress. Validation needs to be pursued both at the method level, to characterise the performance of in vitro methods in relation their ability to detect any association of a chemical with a particular pathway or key toxicological event, and at the methodological level, to assess how integrated approaches can predict toxicological endpoints relevant for regulatory decision making. To facilitate this, more emphasis needs to be given to the development of performance standards that can be applied to classes of methods and integrated approaches that provide similar information. Moreover, the challenge of selecting the right reference chemicals to support validation needs to be addressed more systematically, consistently and in a manner that better reflects the state of the science. Above all however, validation requires true partnership between the development and user communities of alternative methods and the appropriate investment of resources.

Does rational selection of training and test sets improve the outcome of QSAR modeling?

PubMed

Martin, Todd M; Harten, Paul; Young, Douglas M; Muratov, Eugene N; Golbraikh, Alexander; Zhu, Hao; Tropsha, Alexander

2012-10-22

Prior to using a quantitative structure activity relationship (QSAR) model for external predictions, its predictive power should be established and validated. In the absence of a true external data set, the best way to validate the predictive ability of a model is to perform its statistical external validation. In statistical external validation, the overall data set is divided into training and test sets. Commonly, this splitting is performed using random division. Rational splitting methods can divide data sets into training and test sets in an intelligent fashion. The purpose of this study was to determine whether rational division methods lead to more predictive models compared to random division. A special data splitting procedure was used to facilitate the comparison between random and rational division methods. For each toxicity end point, the overall data set was divided into a modeling set (80% of the overall set) and an external evaluation set (20% of the overall set) using random division. The modeling set was then subdivided into a training set (80% of the modeling set) and a test set (20% of the modeling set) using rational division methods and by using random division. The Kennard-Stone, minimal test set dissimilarity, and sphere exclusion algorithms were used as the rational division methods. The hierarchical clustering, random forest, and k-nearest neighbor (kNN) methods were used to develop QSAR models based on the training sets. For kNN QSAR, multiple training and test sets were generated, and multiple QSAR models were built. The results of this study indicate that models based on rational division methods generate better statistical results for the test sets than models based on random division, but the predictive power of both types of models are comparable.

Experimental Validation of the Dynamic Inertia Measurement Method to Find the Mass Properties of an Iron Bird Test Article

NASA Technical Reports Server (NTRS)

Chin, Alexander W.; Herrera, Claudia Y.; Spivey, Natalie D.; Fladung, William A.; Cloutier, David

2015-01-01

The mass properties of an aerospace vehicle are required by multiple disciplines in the analysis and prediction of flight behavior. Pendulum oscillation methods have been developed and employed for almost a century as a means to measure mass properties. However, these oscillation methods are costly, time consuming, and risky. The NASA Armstrong Flight Research Center has been investigating the Dynamic Inertia Measurement, or DIM method as a possible alternative to oscillation methods. The DIM method uses ground test techniques that are already applied to aerospace vehicles when conducting modal surveys. Ground vibration tests would require minimal additional instrumentation and time to apply the DIM method. The DIM method has been validated on smaller test articles, but has not yet been fully proven on large aerospace vehicles.

Performance validity testing in neuropsychology: a clinical guide, critical review, and update on a rapidly evolving literature.

PubMed

Lippa, Sara M

2018-04-01

Over the past two decades, there has been much research on measures of response bias and myriad measures have been validated in a variety of clinical and research samples. This critical review aims to guide clinicians through the use of performance validity tests (PVTs) from test selection and administration through test interpretation and feedback. Recommended cutoffs and relevant test operating characteristics are presented. Other important issues to consider during test selection, administration, interpretation, and feedback are discussed including order effects, coaching, impact on test data, and methods to combine measures and improve predictive power. When interpreting performance validity measures, neuropsychologists must use particular caution in cases of dementia, low intelligence, English as a second language/minority cultures, or low education. PVTs provide valuable information regarding response bias and, under the right circumstances, can provide excellent evidence of response bias. Only after consideration of the entire clinical picture, including validity test performance, can concrete determinations regarding the validity of test data be made.

A multivariate model and statistical method for validating tree grade lumber yield equations

Treesearch

Donald W. Seegrist

1975-01-01

Lumber yields within lumber grades can be described by a multivariate linear model. A method for validating lumber yield prediction equations when there are several tree grades is presented. The method is based on multivariate simultaneous test procedures.

Psychological Testing and Psychological Assessment: A Review of Evidence and Issues.

ERIC Educational Resources Information Center

Meyer, Gregory J.; Finn, Stephen E.; Eyde, Lorraine D.; Kay, Gary G.; Moreland, Kevin L.; Dies, Robert R.; Eisman, Elena J.; Kubiszyn, Tom W.; Reed, Geoffrey M.

2001-01-01

Summarizes issues associated with psychological assessment, concluding that: psychological test validity is strong and is comparable to medical test validity; distinct assessment methods provide unique sources of information; and clinicians who rely solely on interviews are prone to incomplete understandings. Suggests that multimethod assessment…

Student mathematical imagination instruments: construction, cultural adaptation and validity

NASA Astrophysics Data System (ADS)

Dwijayanti, I.; Budayasa, I. K.; Siswono, T. Y. E.

2018-03-01

Imagination has an important role as the center of sensorimotor activity of the students. The purpose of this research is to construct the instrument of students’ mathematical imagination in understanding concept of algebraic expression. The researcher performs validity using questionnaire and test technique and data analysis using descriptive method. Stages performed include: 1) the construction of the embodiment of the imagination; 2) determine the learning style questionnaire; 3) construct instruments; 4) translate to Indonesian as well as adaptation of learning style questionnaire content to student culture; 5) perform content validation. The results stated that the constructed instrument is valid by content validation and empirical validation so that it can be used with revisions. Content validation involves Indonesian linguists, english linguists and mathematics material experts. Empirical validation is done through a legibility test (10 students) and shows that in general the language used can be understood. In addition, a questionnaire test (86 students) was analyzed using a biserial point correlation technique resulting in 16 valid items with a reliability test using KR 20 with medium reability criteria. While the test instrument test (32 students) to find all items are valid and reliability test using KR 21 with reability is 0,62.

Verification and Validation Process for Progressive Damage and Failure Analysis Methods in the NASA Advanced Composites Consortium

NASA Technical Reports Server (NTRS)

Wanthal, Steven; Schaefer, Joseph; Justusson, Brian; Hyder, Imran; Engelstad, Stephen; Rose, Cheryl

2017-01-01

The Advanced Composites Consortium is a US Government/Industry partnership supporting technologies to enable timeline and cost reduction in the development of certified composite aerospace structures. A key component of the consortium's approach is the development and validation of improved progressive damage and failure analysis methods for composite structures. These methods will enable increased use of simulations in design trade studies and detailed design development, and thereby enable more targeted physical test programs to validate designs. To accomplish this goal with confidence, a rigorous verification and validation process was developed. The process was used to evaluate analysis methods and associated implementation requirements to ensure calculation accuracy and to gage predictability for composite failure modes of interest. This paper introduces the verification and validation process developed by the consortium during the Phase I effort of the Advanced Composites Project. Specific structural failure modes of interest are first identified, and a subset of standard composite test articles are proposed to interrogate a progressive damage analysis method's ability to predict each failure mode of interest. Test articles are designed to capture the underlying composite material constitutive response as well as the interaction of failure modes representing typical failure patterns observed in aerospace structures.

AFNOR validation of Premi Test, a microbiological-based screening tube-test for the detection of antimicrobial residues in animal muscle tissue.

PubMed

Gaudin, Valerie; Juhel-Gaugain, Murielle; Morétain, Jean-Pierre; Sanders, Pascal

2008-12-01

Premi Test contains viable spores of a strain of Bacillus stearothermophilus which is sensitive to antimicrobial residues, such as beta-lactams, tetracyclines, macrolides and sulphonamides. The growth of the strain is inhibited by the presence of antimicrobial residues in muscle tissue samples. Premi Test was validated according to AFNOR rules (French Association for Normalisation). The AFNOR validation was based on the comparison of reference methods (French Official method, i.e. four plate test (FPT) and the STAR protocol (five plate test)) with the alternative method (Premi Test). A preliminary study was conducted in an expert laboratory (Community Reference Laboratory, CRL) on both spiked and incurred samples (field samples). Several method performance criteria (sensitivity, specificity, relative accuracy) were estimated and are discussed, in addition to detection capabilities. Adequate agreement was found between the alternative method and the reference methods. However, Premi Test was more sensitive to beta-lactams and sulphonamides than the FPT. Subsequently, a collaborative study with 11 laboratories was organised by the CRL. Blank and spiked meat juice samples were sent to participants. The expert laboratory (CRL) statistically analysed the results. It was concluded that Premi Test could be used for the routine determination of antimicrobial residues in muscle of different animal origin with acceptable analytical performance. The detection capabilities of Premi Test for beta-lactams (amoxicillin, ceftiofur), one macrolide (tylosin) and tetracycline were at the level of the respective maximum residue limits (MRL) in muscle samples or even lower.

Iridology: A systematic review.

PubMed

Ernst, E

1999-02-01

Iridologists claim to be able to diagnose medical conditions through abnormalities of pigmentation in the iris. This technique is popular in many countries. Therefore it is relevant to ask whether it is valid. To systematically review all interpretable tests of the validity of iridology as a diagnostic tool. DATA SOURCE AND EXTRACTION: Three independent literature searches were performed to identify all blinded tests. Data were extracted in a predefined, standardized fashion. Four case control studies were found. The majority of these investigations suggests that iridology is not a valid diagnostic method. The validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.

Applied Chaos Level Test for Validation of Signal Conditions Underlying Optimal Performance of Voice Classification Methods.

PubMed

Liu, Boquan; Polce, Evan; Sprott, Julien C; Jiang, Jack J

2018-05-17

The purpose of this study is to introduce a chaos level test to evaluate linear and nonlinear voice type classification method performances under varying signal chaos conditions without subjective impression. Voice signals were constructed with differing degrees of noise to model signal chaos. Within each noise power, 100 Monte Carlo experiments were applied to analyze the output of jitter, shimmer, correlation dimension, and spectrum convergence ratio. The computational output of the 4 classifiers was then plotted against signal chaos level to investigate the performance of these acoustic analysis methods under varying degrees of signal chaos. A diffusive behavior detection-based chaos level test was used to investigate the performances of different voice classification methods. Voice signals were constructed by varying the signal-to-noise ratio to establish differing signal chaos conditions. Chaos level increased sigmoidally with increasing noise power. Jitter and shimmer performed optimally when the chaos level was less than or equal to 0.01, whereas correlation dimension was capable of analyzing signals with chaos levels of less than or equal to 0.0179. Spectrum convergence ratio demonstrated proficiency in analyzing voice signals with all chaos levels investigated in this study. The results of this study corroborate the performance relationships observed in previous studies and, therefore, demonstrate the validity of the validation test method. The presented chaos level validation test could be broadly utilized to evaluate acoustic analysis methods and establish the most appropriate methodology for objective voice analysis in clinical practice.

Testing and Validation of Computational Methods for Mass Spectrometry.

PubMed

Gatto, Laurent; Hansen, Kasper D; Hoopmann, Michael R; Hermjakob, Henning; Kohlbacher, Oliver; Beyer, Andreas

2016-03-04

High-throughput methods based on mass spectrometry (proteomics, metabolomics, lipidomics, etc.) produce a wealth of data that cannot be analyzed without computational methods. The impact of the choice of method on the overall result of a biological study is often underappreciated, but different methods can result in very different biological findings. It is thus essential to evaluate and compare the correctness and relative performance of computational methods. The volume of the data as well as the complexity of the algorithms render unbiased comparisons challenging. This paper discusses some problems and challenges in testing and validation of computational methods. We discuss the different types of data (simulated and experimental validation data) as well as different metrics to compare methods. We also introduce a new public repository for mass spectrometric reference data sets ( http://compms.org/RefData ) that contains a collection of publicly available data sets for performance evaluation for a wide range of different methods.

The predictive validity of a situational judgement test, a clinical problem solving test and the core medical training selection methods for performance in specialty training .

PubMed

Patterson, Fiona; Lopes, Safiatu; Harding, Stephen; Vaux, Emma; Berkin, Liz; Black, David

2017-02-01

The aim of this study was to follow up a sample of physicians who began core medical training (CMT) in 2009. This paper examines the long-term validity of CMT and GP selection methods in predicting performance in the Membership of Royal College of Physicians (MRCP(UK)) examinations. We performed a longitudinal study, examining the extent to which the GP and CMT selection methods (T1) predict performance in the MRCP(UK) examinations (T2). A total of 2,569 applicants from 2008-09 who completed CMT and GP selection methods were included in the study. Looking at MRCP(UK) part 1, part 2 written and PACES scores, both CMT and GP selection methods show evidence of predictive validity for the outcome variables, and hierarchical regressions show the GP methods add significant value to the CMT selection process. CMT selection methods predict performance in important outcomes and have good evidence of validity; the GP methods may have an additional role alongside the CMT selection methods. © Royal College of Physicians 2017. All rights reserved.

Development of Modal Test Techniques for Validation of a Solar Sail Design

NASA Technical Reports Server (NTRS)

Gaspar, James L.; Mann, Troy; Behun, Vaughn; Wilkie, W. Keats; Pappa, Richard

2004-01-01

This paper focuses on the development of modal test techniques for validation of a solar sail gossamer space structure design. The major focus is on validating and comparing the capabilities of various excitation techniques for modal testing solar sail components. One triangular shaped quadrant of a solar sail membrane was tested in a 1 Torr vacuum environment using various excitation techniques including, magnetic excitation, and surface-bonded piezoelectric patch actuators. Results from modal tests performed on the sail using piezoelectric patches at different positions are discussed. The excitation methods were evaluated for their applicability to in-vacuum ground testing and to the development of on orbit flight test techniques. The solar sail membrane was tested in the horizontal configuration at various tension levels to assess the variation in frequency with tension in a vacuum environment. A segment of a solar sail mast prototype was also tested in ambient atmospheric conditions using various excitation techniques, and these methods are also assessed for their ground test capabilities and on-orbit flight testing.

Catch-up validation study of an in vitro skin irritation test method based on an open source reconstructed epidermis (phase II).

PubMed

Groeber, F; Schober, L; Schmid, F F; Traube, A; Kolbus-Hernandez, S; Daton, K; Hoffmann, S; Petersohn, D; Schäfer-Korting, M; Walles, H; Mewes, K R

2016-10-01

To replace the Draize skin irritation assay (OECD guideline 404) several test methods based on reconstructed human epidermis (RHE) have been developed and were adopted in the OECD test guideline 439. However, all validated test methods in the guideline are linked to RHE provided by only three companies. Thus, the availability of these test models is dependent on the commercial interest of the producer. To overcome this limitation and thus to increase the accessibility of in vitro skin irritation testing, an open source reconstructed epidermis (OS-REp) was introduced. To demonstrate the capacity of the OS-REp in regulatory risk assessment, a catch-up validation study was performed. The participating laboratories used in-house generated OS-REp to assess the set of 20 reference substances according to the performance standards amending the OECD test guideline 439. Testing was performed under blinded conditions. The within-laboratory reproducibility of 87% and the inter-laboratory reproducibility of 85% prove a high reliability of irritancy testing using the OS-REp protocol. In addition, the prediction capacity was with an accuracy of 80% comparable to previous published RHE based test protocols. Taken together the results indicate that the OS-REp test method can be used as a standalone alternative skin irritation test replacing the OECD test guideline 404. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

TEST METHODS TO DETERMINE THE MERCURY EMISSIONS FROM SLUDGE INCINERATION PLANTS

EPA Science Inventory

Two test methods for mercury are described along with the laboratory and field studies done in developing and validating them. One method describes how to homogenize and analyze large quantities of sewage sludge. The other test method describes how to measure the mercury emission...

Overview of Heat Addition and Efficiency Predictions for an Advanced Stirling Convertor

NASA Technical Reports Server (NTRS)

Wilson, Scott D.; Reid, Terry; Schifer, Nicholas; Briggs, Maxwell

2011-01-01

Past methods of predicting net heat input needed to be validated. Validation effort pursued with several paths including improving model inputs, using test hardware to provide validation data, and validating high fidelity models. Validation test hardware provided direct measurement of net heat input for comparison to predicted values. Predicted value of net heat input was 1.7 percent less than measured value and initial calculations of measurement uncertainty were 2.1 percent (under review). Lessons learned during validation effort were incorporated into convertor modeling approach which improved predictions of convertor efficiency.

Nonclinical dose formulation analysis method validation and sample analysis.

PubMed

Whitmire, Monica Lee; Bryan, Peter; Henry, Teresa R; Holbrook, John; Lehmann, Paul; Mollitor, Thomas; Ohorodnik, Susan; Reed, David; Wietgrefe, Holly D

2010-12-01

Nonclinical dose formulation analysis methods are used to confirm test article concentration and homogeneity in formulations and determine formulation stability in support of regulated nonclinical studies. There is currently no regulatory guidance for nonclinical dose formulation analysis method validation or sample analysis. Regulatory guidance for the validation of analytical procedures has been developed for drug product/formulation testing; however, verification of the formulation concentrations falls under the framework of GLP regulations (not GMP). The only current related regulatory guidance is the bioanalytical guidance for method validation. The fundamental parameters for bioanalysis and formulation analysis validations that overlap include: recovery, accuracy, precision, specificity, selectivity, carryover, sensitivity, and stability. Divergence in bioanalytical and drug product validations typically center around the acceptance criteria used. As the dose formulation samples are not true "unknowns", the concept of quality control samples that cover the entire range of the standard curve serving as the indication for the confidence in the data generated from the "unknown" study samples may not always be necessary. Also, the standard bioanalytical acceptance criteria may not be directly applicable, especially when the determined concentration does not match the target concentration. This paper attempts to reconcile the different practices being performed in the community and to provide recommendations of best practices and proposed acceptance criteria for nonclinical dose formulation method validation and sample analysis.

Validation of catchment models for predicting land-use and climate change impacts. 1. Method

NASA Astrophysics Data System (ADS)

Ewen, J.; Parkin, G.

1996-02-01

Computer simulation models are increasingly being proposed as tools capable of giving water resource managers accurate predictions of the impact of changes in land-use and climate. Previous validation testing of catchment models is reviewed, and it is concluded that the methods used do not clearly test a model's fitness for such a purpose. A new generally applicable method is proposed. This involves the direct testing of fitness for purpose, uses established scientific techniques, and may be implemented within a quality assured programme of work. The new method is applied in Part 2 of this study (Parkin et al., J. Hydrol., 175:595-613, 1996).

Performance Tested Method multiple laboratory validation study of ELISA-based assays for the detection of peanuts in food.

PubMed

Park, Douglas L; Coates, Scott; Brewer, Vickery A; Garber, Eric A E; Abouzied, Mohamed; Johnson, Kurt; Ritter, Bruce; McKenzie, Deborah

2005-01-01

Performance Tested Method multiple laboratory validations for the detection of peanut protein in 4 different food matrixes were conducted under the auspices of the AOAC Research Institute. In this blind study, 3 commercially available ELISA test kits were validated: Neogen Veratox for Peanut, R-Biopharm RIDASCREEN FAST Peanut, and Tepnel BioKits for Peanut Assay. The food matrixes used were breakfast cereal, cookies, ice cream, and milk chocolate spiked at 0 and 5 ppm peanut. Analyses of the samples were conducted by laboratories representing industry and international and U.S governmental agencies. All 3 commercial test kits successfully identified spiked and peanut-free samples. The validation study required 60 analyses on test samples at the target level 5 microg peanut/g food and 60 analyses at a peanut-free level, which was designed to ensure that the lower 95% confidence limit for the sensitivity and specificity would not be <90%. The probability that a test sample contains an allergen given a prevalence rate of 5% and a positive test result using a single test kit analysis with 95% sensitivity and 95% specificity, which was demonstrated for these test kits, would be 50%. When 2 test kits are run simultaneously on all samples, the probability becomes 95%. It is therefore recommended that all field samples be analyzed with at least 2 of the validated kits.

Glossary of reference terms for alternative test methods and their validation.

PubMed

Ferrario, Daniele; Brustio, Roberta; Hartung, Thomas

2014-01-01

This glossary was developed to provide technical references to support work in the field of the alternatives to animal testing. It was compiled from various existing reference documents coming from different sources and is meant to be a point of reference on alternatives to animal testing. Giving the ever-increasing number of alternative test methods and approaches being developed over the last decades, a combination, revision, and harmonization of earlier published collections of terms used in the validation of such methods is required. The need to update previous glossary efforts came from the acknowledgement that new words have emerged with the development of new approaches, while others have become obsolete, and the meaning of some terms has partially changed over time. With this glossary we intend to provide guidance on issues related to the validation of new or updated testing methods consistent with current approaches. Moreover, because of new developments and technologies, a glossary needs to be a living, constantly updated document. An Internet-based version based on this compilation may be found at http://altweb.jhsph.edu/, allowing the addition of new material.

Validation of methods on formalin testing in tofu and determination of 3,5-diacetyl-dihydrolutidine stability by UV-Vis spectrophotometry

NASA Astrophysics Data System (ADS)

Rohyami, Yuli; Pribadi, Rizki Maulana

2017-12-01

Formalin is a food preservative that is prohibited by the government, but the abuse of these chemicals is still widely found. The presence of formalin can be detected by using a typical reagent that can ensure the presence of formaldehyde qualitatively and quantitatively. This research was conducted to validate the method of determining formalin in tofu by using Nash reagent in UV-Vis spectrophotometry. The addition of Nash reagent will lead to the formation of diacetyldihydrolutidin complex. The study was performed by stability test of deacetyldihydrolutidine complex against time and pH. Validation of methods for formalin testing in tofu with diacetyldihydrolutidine by UV-Vis spectrophotometry. The results showed that 3,5-diacetyl-dihydrolutidine complex is stable at pH of 7 and stable in the range of 70-120 minutes. The validation shows that the method gives good precision and accuracy of 83.78%. The method has the limit of detection of 1.3681 µg/mL, limit of quantification of 4,5603 µg/mL, and the estimated uncertainty of measurement of 1.30 µg/mL. The test showed that the tofu contained formalin 3.09 ± 1.30 µg/mL. These values provide information that this method can be used as a procedure for the determination of formalin on tofu.

Multi-body modeling method for rollover using MADYMO

NASA Astrophysics Data System (ADS)

Liu, Changye; Lin, Zhigui; Lv, Juncheng; Luo, Qinyue; Qin, Zhenyao; Zhang, Pu; Chen, Tao

2017-04-01

Rollovers are complex road accidents causing a big deal of fatalities. FE model for rollover study will costtoo much time due to its long duration.A new multi-body modeling method is proposed in this paper which can save a lot of time and has high-fidelity meanwhile. Following works were carried out to validate this new method. First, a small van was tested following the FMVSS 208 protocol for the validation of the proposed modeling method. Second, a MADYMO model of this small van was reconstructed. The vehicle body was divided into two main parts, the deformable upper body and the rigid lower body, modeled by different waysbased on an FE model. The specific method of modeling is offered in this paper. Finally, the trajectories of the vehicle from test and simulation were comparedand the match was very good. Acceleration of left B pillar was taken into consideration, which turned out fitting the test result well in the time of event. The final deformation status of the vehicle in test and simulation showed similar trend. This validated model provides a reliable wayfor further research in occupant injuries during rollovers.

Validation protocol of analytical procedures for quantification of drugs in polymeric systems for parenteral administration: dexamethasone phosphate disodium microparticles.

PubMed

Martín-Sabroso, Cristina; Tavares-Fernandes, Daniel Filipe; Espada-García, Juan Ignacio; Torres-Suárez, Ana Isabel

2013-12-15

In this work a protocol to validate analytical procedures for the quantification of drug substances formulated in polymeric systems that comprise both drug entrapped into the polymeric matrix (assay:content test) and drug released from the systems (assay:dissolution test) is developed. This protocol is applied to the validation two isocratic HPLC analytical procedures for the analysis of dexamethasone phosphate disodium microparticles for parenteral administration. Preparation of authentic samples and artificially "spiked" and "unspiked" samples is described. Specificity (ability to quantify dexamethasone phosphate disodium in presence of constituents of the dissolution medium and other microparticle constituents), linearity, accuracy and precision are evaluated, in the range from 10 to 50 μg mL(-1) in the assay:content test procedure and from 0.25 to 10 μg mL(-1) in the assay:dissolution test procedure. The robustness of the analytical method to extract drug from microparticles is also assessed. The validation protocol developed allows us to conclude that both analytical methods are suitable for their intended purpose, but the lack of proportionality of the assay:dissolution analytical method should be taken into account. The validation protocol designed in this work could be applied to the validation of any analytical procedure for the quantification of drugs formulated in controlled release polymeric microparticles. Copyright © 2013 Elsevier B.V. All rights reserved.

Construct Validity and Scoring Methods of the World Health Organization: Health and Work Performance Questionnaire Among Workers With Arthritis and Rheumatological Conditions.

PubMed

AlHeresh, Rawan; LaValley, Michael P; Coster, Wendy; Keysor, Julie J

2017-06-01

To evaluate construct validity and scoring methods of the world health organization-health and work performance questionnaire (HPQ) for people with arthritis. Construct validity was examined through hypothesis testing using the recommended guidelines of the consensus-based standards for the selection of health measurement instruments (COSMIN). The HPQ using the absolute scoring method showed moderate construct validity as four of the seven hypotheses were met. The HPQ using the relative scoring method had weak construct validity as only one of the seven hypotheses were met. The absolute scoring method for the HPQ is superior in construct validity to the relative scoring method in assessing work performance among people with arthritis and related rheumatic conditions; however, more research is needed to further explore other psychometric properties of the HPQ.

Reliability and Validity of the Footprint Assessment Method Using Photoshop CS5 Software in Young People with Down Syndrome.

PubMed

Gutiérrez-Vilahú, Lourdes; Massó-Ortigosa, Núria; Rey-Abella, Ferran; Costa-Tutusaus, Lluís; Guerra-Balic, Myriam

2016-05-01

People with Down syndrome present skeletal abnormalities in their feet that can be analyzed by commonly used gold standard indices (the Hernández-Corvo index, the Chippaux-Smirak index, the Staheli arch index, and the Clarke angle) based on footprint measurements. The use of Photoshop CS5 software (Adobe Systems Software Ireland Ltd, Dublin, Ireland) to measure footprints has been validated in the general population. The present study aimed to assess the reliability and validity of this footprint assessment technique in the population with Down syndrome. Using optical podography and photography, 44 footprints from 22 patients with Down syndrome (11 men [mean ± SD age, 23.82 ± 3.12 years] and 11 women [mean ± SD age, 24.82 ± 6.81 years]) were recorded in a static bipedal standing position. A blinded observer performed the measurements using a validated manual method three times during the 4-month study, with 2 months between measurements. Test-retest was used to check the reliability of the Photoshop CS5 software measurements. Validity and reliability were obtained by intraclass correlation coefficient (ICC). The reliability test for all of the indices showed very good values for the Photoshop CS5 method (ICC, 0.982-0.995). Validity testing also found no differences between the techniques (ICC, 0.988-0.999). The Photoshop CS5 software method is reliable and valid for the study of footprints in young people with Down syndrome.

Reliability and Validity of the Footprint Assessment Method Using Photoshop CS5 Software.

PubMed

Gutiérrez-Vilahú, Lourdes; Massó-Ortigosa, Núria; Costa-Tutusaus, Lluís; Guerra-Balic, Myriam

2015-05-01

Several sophisticated methods of footprint analysis currently exist. However, it is sometimes useful to apply standard measurement methods of recognized evidence with an easy and quick application. We sought to assess the reliability and validity of a new method of footprint assessment in a healthy population using Photoshop CS5 software (Adobe Systems Inc, San Jose, California). Forty-two footprints, corresponding to 21 healthy individuals (11 men with a mean ± SD age of 20.45 ± 2.16 years and 10 women with a mean ± SD age of 20.00 ± 1.70 years) were analyzed. Footprints were recorded in static bipedal standing position using optical podography and digital photography. Three trials for each participant were performed. The Hernández-Corvo, Chippaux-Smirak, and Staheli indices and the Clarke angle were calculated by manual method and by computerized method using Photoshop CS5 software. Test-retest was used to determine reliability. Validity was obtained by intraclass correlation coefficient (ICC). The reliability test for all of the indices showed high values (ICC, 0.98-0.99). Moreover, the validity test clearly showed no difference between techniques (ICC, 0.99-1). The reliability and validity of a method to measure, assess, and record the podometric indices using Photoshop CS5 software has been demonstrated. This provides a quick and accurate tool useful for the digital recording of morphostatic foot study parameters and their control.

Review on pen-and-paper-based observational methods for assessing ergonomic risk factors of computer work.

PubMed

Rahman, Mohd Nasrull Abdol; Mohamad, Siti Shafika

2017-01-01

Computer works are associated with Musculoskeletal Disorders (MSDs). There are several methods have been developed to assess computer work risk factor related to MSDs. This review aims to give an overview of current techniques available for pen-and-paper-based observational methods in assessing ergonomic risk factors of computer work. We searched an electronic database for materials from 1992 until 2015. The selected methods were focused on computer work, pen-and-paper observational methods, office risk factors and musculoskeletal disorders. This review was developed to assess the risk factors, reliability and validity of pen-and-paper observational method associated with computer work. Two evaluators independently carried out this review. Seven observational methods used to assess exposure to office risk factor for work-related musculoskeletal disorders were identified. The risk factors involved in current techniques of pen and paper based observational tools were postures, office components, force and repetition. From the seven methods, only five methods had been tested for reliability. They were proven to be reliable and were rated as moderate to good. For the validity testing, from seven methods only four methods were tested and the results are moderate. Many observational tools already exist, but no single tool appears to cover all of the risk factors including working posture, office component, force, repetition and office environment at office workstations and computer work. Although the most important factor in developing tool is proper validation of exposure assessment techniques, the existing observational method did not test reliability and validity. Futhermore, this review could provide the researchers with ways on how to improve the pen-and-paper-based observational method for assessing ergonomic risk factors of computer work.

Bridging the Gap Between Validation and Implementation of Non-Animal Veterinary Vaccine Potency Testing Methods

PubMed Central

Dozier, Samantha; Brown, Jeffrey; Currie, Alistair

2011-01-01

Simple Summary Many vaccines are tested for quality in experiments that require the use of large numbers of animals in procedures that often cause significant pain and distress. Newer technologies have fostered the development of vaccine quality control tests that reduce or eliminate the use of animals, but the availability of these newer methods has not guaranteed their acceptance by regulators or use by manufacturers. We discuss a strategic approach that has been used to assess and ultimately increase the use of non-animal vaccine quality tests in the U.S. and U.K. Abstract In recent years, technologically advanced high-throughput techniques have been developed that replace, reduce or refine animal use in vaccine quality control tests. Following validation, these tests are slowly being accepted for use by international regulatory authorities. Because regulatory acceptance itself has not guaranteed that approved humane methods are adopted by manufacturers, various organizations have sought to foster the preferential use of validated non-animal methods by interfacing with industry and regulatory authorities. After noticing this gap between regulation and uptake by industry, we began developing a paradigm that seeks to narrow the gap and quicken implementation of new replacement, refinement or reduction guidance. A systematic analysis of our experience in promoting the transparent implementation of validated non-animal vaccine potency assays has led to the refinement of our paradigmatic process, presented here, by which interested parties can assess the local regulatory acceptance of methods that reduce animal use and integrate them into quality control testing protocols, or ensure the elimination of peripheral barriers to their use, particularly for potency and other tests carried out on production batches. PMID:26486625

Fecal electrolyte testing for evaluation of unexplained diarrhea: Validation of body fluid test accuracy in the absence of a reference method.

PubMed

Voskoboev, Nikolay V; Cambern, Sarah J; Hanley, Matthew M; Giesen, Callen D; Schilling, Jason J; Jannetto, Paul J; Lieske, John C; Block, Darci R

2015-11-01

Validation of tests performed on body fluids other than blood or urine can be challenging due to the lack of a reference method to confirm accuracy. The aim of this study was to evaluate alternate assessments of accuracy that laboratories can rely on to validate body fluid tests in the absence of a reference method using the example of sodium (Na(+)), potassium (K(+)), and magnesium (Mg(2+)) testing in stool fluid. Validations of fecal Na(+), K(+), and Mg(2+) were performed on the Roche cobas 6000 c501 (Roche Diagnostics) using residual stool specimens submitted for clinical testing. Spiked recovery, mixing studies, and serial dilutions were performed and % recovery of each analyte was calculated to assess accuracy. Results were confirmed by comparison to a reference method (ICP-OES, PerkinElmer). Mean recoveries for fecal electrolytes were Na(+) upon spiking=92%, mixing=104%, and dilution=105%; K(+) upon spiking=94%, mixing=96%, and dilution=100%; and Mg(2+) upon spiking=93%, mixing=98%, and dilution=100%. When autoanalyzer results were compared to reference ICP-OES results, Na(+) had a slope=0.94, intercept=4.1, and R(2)=0.99; K(+) had a slope=0.99, intercept=0.7, and R(2)=0.99; and Mg(2+) had a slope=0.91, intercept=-4.6, and R(2)=0.91. Calculated osmotic gap using both methods were highly correlated with slope=0.95, intercept=4.5, and R(2)=0.97. Acid pretreatment increased magnesium recovery from a subset of clinical specimens. A combination of mixing, spiking, and dilution recovery experiments are an acceptable surrogate for assessing accuracy in body fluid validations in the absence of a reference method. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Development and validation of dissolution study of sustained release dextromethorphan hydrobromide tablets.

PubMed

Rajan, Sekar; Colaco, Socorrina; Ramesh, N; Meyyanathan, Subramania Nainar; Elango, K

2014-02-01

This study describes the development and validation of dissolution tests for sustained release Dextromethorphan hydrobromide tablets using an HPLC method. Chromatographic separation was achieved on a C18 column utilizing 0.5% triethylamine (pH 7.5) and acetonitrile in the ratio of 50:50. The detection wavelength was 280 nm. The method was validated and response was found to be linear in the drug concentration range of 10-80 microg mL(-1). The suitable conditions were clearly decided after testing sink conditions, dissolution medium and agitation intensity. The most excellent dissolution conditions tested, for the Dextromethorphan hydrobromide was applied to appraise the dissolution profiles. The method was validated and response was found to be linear in the drug concentration range of 10-80 microg mL(-1). The method was established to have sufficient intermediate precision as similar separation was achieved on another instrument handled by different operators. Mean Recovery was 101.82%. Intra precisions for three different concentrations were 1.23, 1.10 0.72 and 1.57, 1.69, 0.95 and inter run precisions were % RSD 0.83, 1.36 and 1.57%, respectively. The method was successfully applied for dissolution study of the developed Dextromethorphan hydrobromide tablets.

Identifying and classifying hyperostosis frontalis interna via computerized tomography.

PubMed

May, Hila; Peled, Nathan; Dar, Gali; Hay, Ori; Abbas, Janan; Masharawi, Youssef; Hershkovitz, Israel

2010-12-01

The aim of this study was to recognize the radiological characteristics of hyperostosis frontalis interna (HFI) and to establish a valid and reliable method for its identification and classification. A reliability test was carried out on 27 individuals who had undergone a head computerized tomography (CT) scan. Intra-observer reliability was obtained by examining the images three times, by the same researcher, with a 2-week interval between each sample ranking. The inter-observer test was performed by three independent researchers. A validity test was carried out using two methods for identifying and classifying HFI: 46 cadaver skullcaps were ranked twice via computerized tomography scans and then by direct observation. Reliability and validity were calculated using Kappa test (SPSS 15.0). Reliability tests of ranking HFI via CT scans demonstrated good results (K > 0.7). As for validity, a very good consensus was obtained between the CT and direct observation, when moderate and advanced types of HFI were present (K = 0.82). The suggested classification method for HFI, using CT, demonstrated a sensitivity of 84%, specificity of 90.5%, and positive predictive value of 91.3%. In conclusion, volume rendering is a reliable and valid tool for identifying HFI. The suggested three-scale classification is most suitable for radiological diagnosis of the phenomena. Considering the increasing awareness of HFI as an early indicator of a developing malady, this study may assist radiologists in identifying and classifying the phenomena.

Validation of a new ELISA method for in vitro potency testing of hepatitis A vaccines.

PubMed

Morgeaux, S; Variot, P; Daas, A; Costanzo, A

2013-01-01

The goal of the project was to standardise a new in vitro method in replacement of the existing standard method for the determination of hepatitis A virus antigen content in hepatitis A vaccines (HAV) marketed in Europe. This became necessary due to issues with the method used previously, requiring the use of commercial test kits. The selected candidate method, not based on commercial kits, had already been used for many years by an Official Medicines Control Laboratory (OMCL) for routine testing and batch release of HAV. After a pre-qualification phase (Phase 1) that showed the suitability of the commercially available critical ELISA reagents for the determination of antigen content in marketed HAV present on the European market, an international collaborative study (Phase 2) was carried out in order to fully validate the method. Eleven laboratories took part in the collaborative study. They performed assays with the candidate standard method and, in parallel, for comparison purposes, with their own in-house validated methods where these were available. The study demonstrated that the new assay provides a more reliable and reproducible method when compared to the existing standard method. A good correlation of the candidate standard method with the in vivo immunogenicity assay in mice was shown previously for both potent and sub-potent (stressed) vaccines. Thus, the new standard method validated during the collaborative study may be implemented readily by manufacturers and OMCLs for routine batch release but also for in-process control or consistency testing. The new method was approved in October 2012 by Group of Experts 15 of the European Pharmacopoeia (Ph. Eur.) as the standard method for in vitro potency testing of HAV. The relevant texts will be revised accordingly. Critical reagents such as coating reagent and detection antibodies have been adopted by the Ph. Eur. Commission and are available from the EDQM as Ph. Eur. Biological Reference Reagents (BRRs).

A systematic review of publications assessing reliability and validity of the Behavioral Risk Factor Surveillance System (BRFSS), 2004–2011

PubMed Central

2013-01-01

Background In recent years response rates on telephone surveys have been declining. Rates for the behavioral risk factor surveillance system (BRFSS) have also declined, prompting the use of new methods of weighting and the inclusion of cell phone sampling frames. A number of scholars and researchers have conducted studies of the reliability and validity of the BRFSS estimates in the context of these changes. As the BRFSS makes changes in its methods of sampling and weighting, a review of reliability and validity studies of the BRFSS is needed. Methods In order to assess the reliability and validity of prevalence estimates taken from the BRFSS, scholarship published from 2004–2011 dealing with tests of reliability and validity of BRFSS measures was compiled and presented by topics of health risk behavior. Assessments of the quality of each publication were undertaken using a categorical rubric. Higher rankings were achieved by authors who conducted reliability tests using repeated test/retest measures, or who conducted tests using multiple samples. A similar rubric was used to rank validity assessments. Validity tests which compared the BRFSS to physical measures were ranked higher than those comparing the BRFSS to other self-reported data. Literature which undertook more sophisticated statistical comparisons was also ranked higher. Results Overall findings indicated that BRFSS prevalence rates were comparable to other national surveys which rely on self-reports, although specific differences are noted for some categories of response. BRFSS prevalence rates were less similar to surveys which utilize physical measures in addition to self-reported data. There is very little research on reliability and validity for some health topics, but a great deal of information supporting the validity of the BRFSS data for others. Conclusions Limitations of the examination of the BRFSS were due to question differences among surveys used as comparisons, as well as mode of data collection differences. As the BRFSS moves to incorporating cell phone data and changing weighting methods, a review of reliability and validity research indicated that past BRFSS landline only data were reliable and valid as measured against other surveys. New analyses and comparisons of BRFSS data which include the new methodologies and cell phone data will be needed to ascertain the impact of these changes on estimates in the future. PMID:23522349

Testing Standard Reliability Criteria

ERIC Educational Resources Information Center

Sherry, David

2017-01-01

Maul's paper, "Rethinking Traditional Methods of Survey Validation" (Andrew Maul), contains two stages. First he presents empirical results that cast doubt on traditional methods for validating psychological measurement instruments. These results motivate the second stage, a critique of current conceptions of psychological measurement…

Design and Validation of a Straight-Copy Typewriting Prognostic Test Using Kinesthetic Sensitivity.

ERIC Educational Resources Information Center

Olson, Norma Jean

1979-01-01

Describes the development and application of a kinesthetic sensitivity test to determine whether it is a valid and reliable measure of straight-copy typing speed and accuracy. The author states that this kinesthetic sensitivity instrument may be used as a prognostic aptitude test and recommends administration methods. (MF)

[Validation of three screening tests used for early detection of cervical cancer].

PubMed

Rodriguez-Reyes, Esperanza Rosalba; Cerda-Flores, Ricardo M; Quiñones-Pérez, Juan M; Cortés-Gutiérrez, Elva I

2008-01-01

to evaluate the validity (sensitivity, specificity, and accuracy) of three screening methods used in the early detection of the cervical carcinoma versus the histopathology diagnosis. a selected sample of 107 women attended in the Opportune Detection of Cervicouterine Cancer Program in the Hospital de Zona 46, Instituto Mexicano del Seguro Social in Durango, during the 2003 was included. The application of Papa-nicolaou, acetic acid test, and molecular detection of human papillomavirus, and histopatholgy diagnosis were performed in all the patients at the time of the gynecological exam. The detection and tipification of the human papillomavirus was performed by polymerase chain reaction (PCR) and analysis of polymorphisms of length of restriction fragments (RFLP). Histopathology diagnosis was considered the gold standard. The evaluation of the validity was carried out by the Bayesian method for diagnosis test. the positive cases for acetic acid test, Papanicolaou, and PCR were 47, 22, and 19. The accuracy values were 0.70, 0.80 and 0.99, respectively. since the molecular method showed a greater validity in the early detection of the cervical carcinoma we considered of vital importance its implementation in suitable programs of Opportune Detection of Cervicouterino Cancer Program in Mexico. However, in order to validate this conclusion, cross-sectional studies in different region of country must be carried out.

Validation approach for a fast and simple targeted screening method for 75 antibiotics in meat and aquaculture products using LC-MS/MS.

PubMed

Dubreil, Estelle; Gautier, Sophie; Fourmond, Marie-Pierre; Bessiral, Mélaine; Gaugain, Murielle; Verdon, Eric; Pessel, Dominique

2017-04-01

An approach is described to validate a fast and simple targeted screening method for antibiotic analysis in meat and aquaculture products by LC-MS/MS. The strategy of validation was applied for a panel of 75 antibiotics belonging to different families, i.e., penicillins, cephalosporins, sulfonamides, macrolides, quinolones and phenicols. The samples were extracted once with acetonitrile, concentrated by evaporation and injected into the LC-MS/MS system. The approach chosen for the validation was based on the Community Reference Laboratory (CRL) guidelines for the validation of screening qualitative methods. The aim of the validation was to prove sufficient sensitivity of the method to detect all the targeted antibiotics at the level of interest, generally the maximum residue limit (MRL). A robustness study was also performed to test the influence of different factors. The validation showed that the method is valid to detect and identify 73 antibiotics of the 75 antibiotics studied in meat and aquaculture products at the validation levels.

Field validation of the dnph method for aldehydes and ketones. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Workman, G.S.; Steger, J.L.

1996-04-01

A stationary source emission test method for selected aldehydes and ketones has been validated. The method employs a sampling train with impingers containing 2,4-dinitrophenylhydrazine (DNPH) to derivatize the analytes. The resulting hydrazones are recovered and analyzed by high performance liquid chromatography. Nine analytes were studied; the method was validated for formaldehyde, acetaldehyde, propionaldehyde, acetophenone and isophorone. Acrolein, menthyl ethyl ketone, menthyl isobutyl ketone, and quinone did not meet the validation criteria. The study employed the validation techniques described in EPA method 301, which uses train spiking to determine bias, and collocated sampling trains to determine precision. The studies were carriedmore » out at a plywood veneer dryer and a polyester manufacturing plant.« less

The Validity and Reliability Test of the Indonesian Version of Gastroesophageal Reflux Disease Quality of Life (GERD-QOL) Questionnaire.

PubMed

Siahaan, Laura A; Syam, Ari F; Simadibrata, Marcellus; Setiati, Siti

2017-01-01

to obtain a valid and reliable GERD-QOL questionnaire for Indonesian application. at the initial stage, the GERD-QOL questionnaire was first translated into Indonesian language and the translated questionnaire was subsequently translated back into the original language (back-to-back translation). The results were evaluated by the researcher team and therefore, an Indonesian version of GERD-QOL questionnaire was developed. Ninety-one patients who had been clinically diagnosed with GERD based on the Montreal criteria were interviewed using the Indonesian version of GERD-QOL questionnaire and the SF 36 questionnaire. The validity was evaluated using a method of construct validity and external validity, and reliability can be tested by the method of internal consistency and test retest. the Indonesian version of GERD-QOL questionnaire had a good internal consistency reliability with a Cronbach Alpha of 0.687-0.842 and a good test retest reliability with an intra-class correlation coefficient of 0.756-0.936; p<0.05). The questionnaire had also been demonstrated to have a good validity with a proven high correlation to each question of SF-36 (p<0.05). the Indonesian version of GERD-QOL questionnaire has been proven valid and reliable to evaluate the quality of life of GERD patients.

A long-term validation of the modernised DC-ARC-OES solid-sample method.

PubMed

Flórián, K; Hassler, J; Förster, O

2001-12-01

The validation procedure based on ISO 17025 standard has been used to study and illustrate both the longterm stability of the calibration process of the DC-ARC solid sample spectrometric method and the main validation criteria of the method. In the calculation of the validation characteristics depending on the linearity(calibration), also the fulfilment of predetermining criteria such as normality and homoscedasticity was checked. In order to decide whether there are any trends in the time-variation of the analytical signal or not, also the Neumann test of trend was applied and evaluated. Finally, a comparison with similar validation data of the ETV-ICP-OES method was carried out.

Validation of Helicopter Gear Condition Indicators Using Seeded Fault Tests

NASA Technical Reports Server (NTRS)

Dempsey, Paula; Brandon, E. Bruce

2013-01-01

A "seeded fault test" in support of a rotorcraft condition based maintenance program (CBM), is an experiment in which a component is tested with a known fault while health monitoring data is collected. These tests are performed at operating conditions comparable to operating conditions the component would be exposed to while installed on the aircraft. Performance of seeded fault tests is one method used to provide evidence that a Health Usage Monitoring System (HUMS) can replace current maintenance practices required for aircraft airworthiness. Actual in-service experience of the HUMS detecting a component fault is another validation method. This paper will discuss a hybrid validation approach that combines in service-data with seeded fault tests. For this approach, existing in-service HUMS flight data from a naturally occurring component fault will be used to define a component seeded fault test. An example, using spiral bevel gears as the targeted component, will be presented. Since the U.S. Army has begun to develop standards for using seeded fault tests for HUMS validation, the hybrid approach will be mapped to the steps defined within their Aeronautical Design Standard Handbook for CBM. This paper will step through their defined processes, and identify additional steps that may be required when using component test rig fault tests to demonstrate helicopter CI performance. The discussion within this paper will provide the reader with a better appreciation for the challenges faced when defining a seeded fault test for HUMS validation.

Dynamic leg length asymmetry during gait is not a valid method for estimating mild anatomic leg length discrepancy.

PubMed

Leporace, Gustavo; Batista, Luiz Alberto; Serra Cruz, Raphael; Zeitoune, Gabriel; Cavalin, Gabriel Armondi; Metsavaht, Leonardo

2018-03-01

The purpose of this study was to test the validity of dynamic leg length discrepancy (DLLD) during gait as a radiation-free screening method for measuring anatomic leg length discrepancy (ALLD). Thirty-three subjects with mild leg length discrepancy walked along a walkway and the dynamic leg length discrepancy (DLLD) was calculated using a motion analysis system. Pearson correlation and paired Student t -tests were applied to calculate the correlation and compare the differences between DLLD and ALLD (α = 0.05). The results of our study showed DLLD is not a valid method to predict ALLD in subjects with mild limb discrepancy.

Evaluation of the Thermo Scientific SureTect Listeria species assay. AOAC Performance Tested Method 071304.

PubMed

Cloke, Jonathan; Evans, Katharine; Crabtree, David; Hughes, Annette; Simpson, Helen; Holopainen, Jani; Wickstrand, Nina; Kauppinen, Mikko; Leon-Velarde, Carlos; Larson, Nathan; Dave, Keron

2014-01-01

The Thermo Scientific SureTect Listeria species Assay is a new real-time PCR assay for the detection of all species of Listeria in food and environmental samples. This validation study was conducted using the AOAC Research Institute (RI) Performance Tested Methods program to validate the SureTect Listeria species Assay in comparison to the reference method detailed in International Organization for Standardization 11290-1:1996 including amendment 1:2004 in a variety of foods plus plastic and stainless steel. The food matrixes validated were smoked salmon, processed cheese, fresh bagged spinach, cantaloupe, cooked prawns, cooked sliced turkey meat, cooked sliced ham, salami, pork frankfurters, and raw ground beef. All matrixes were tested by Thermo Fisher Scientific, Microbiology Division, Basingstoke, UK. In addition, three matrixes (pork frankfurters, fresh bagged spinach, and stainless steel surface samples) were analyzed independently as part of the AOAC-RI-controlled independent laboratory study by the University ofGuelph, Canada. Using probability of detection statistical analysis, a significant difference in favour of the SureTect assay was demonstrated between the SureTect and reference method for high level spiked samples of pork frankfurters, smoked salmon, cooked prawns, stainless steel, and low-spiked samples of salami. For all other matrixes, no significant difference was seen between the two methods during the study. Inclusivity testing was conducted with 68 different isolates of Listeria species, all of which were detected by the SureTect Listeria species Assay. None of the 33 exclusivity isolates were detected by the SureTect Listeria species Assay. Ruggedness testing was conducted to evaluate the performance of the assay with specific method deviations outside of the recommended parameters open to variation, which demonstrated that the assay gave reliable performance. Accelerated stability testing was additionally conducted, validating the assay shelf life.

Process Skill Assessment Instrument: Innovation to measure student’s learning result holistically

NASA Astrophysics Data System (ADS)

Azizah, K. N.; Ibrahim, M.; Widodo, W.

2018-01-01

Science process skills (SPS) are very important skills for students. However, the fact that SPS is not being main concern in the primary school learning is undeniable. This research aimed to develop a valid, practical, and effective assessment instrument to measure student’s SPS. Assessment instruments comprise of worksheet and test. This development research used one group pre-test post-test design. Data were obtained with validation, observation, and test method to investigate validity, practicality, and the effectivenss of the instruments. Results showed that the validity of assessment instruments is very valid, the reliability is categorized as reliable, student SPS activities have a high percentage, and there is significant improvement on student’s SPS score. It can be concluded that assessment instruments of SPS are valid, practical, and effective to be used to measure student’s SPS result.

Validation of the breast evaluation questionnaire for breast hypertrophy and breast reduction.

PubMed

Lewin, Richard; Elander, Anna; Lundberg, Jonas; Hansson, Emma; Thorarinsson, Andri; Claudelin, Malin; Bladh, Helena; Lidén, Mattias

2018-06-13

There is a lack of published, validated questionnaires for evaluating psychosocial morbidity in patients with breast hypertrophy undergoing breast reduction surgery. To validate the breast evaluation questionnaire (BEQ), originally developed for the assessment of breast augmentation patients, for the assessment of psychosocial morbidity in patients with breast hypertrophy undergoing breast reduction surgery. Validation study Subjects: Women with macromastia Methods: The validation of the BEQ, adapted to breast reduction, was performed in several steps. Content validity, reliability, construct validity and responsiveness were assessed. The original version was adjusted according to the results for content validity and resulted in item reduction and a modified BEQ (mBEQ) that was then assessed for reliability, construct validity and responsiveness. Internal and external validation was performed for the modified BEQ. Convergent validity was tested against Breast-Q (reduction) and discriminate validity was tested against the SF-36. Known-groups validation revealed significant differences between the normal population and patients undergoing breast reduction surgery. The BEQ showed good reliability by test-re-test analysis and high responsiveness. The modified BEQ may be reliable, valid and responsive instrument for assessing women who undergo breast reduction.

Methods to validate the accuracy of an indirect calorimeter in the in-vitro setting.

PubMed

Oshima, Taku; Ragusa, Marco; Graf, Séverine; Dupertuis, Yves Marc; Heidegger, Claudia-Paula; Pichard, Claude

2017-12-01

The international ICALIC initiative aims at developing a new indirect calorimeter according to the needs of the clinicians and researchers in the field of clinical nutrition and metabolism. The project initially focuses on validating the calorimeter for use in mechanically ventilated acutely ill adult patient. However, standard methods to validate the accuracy of calorimeters have not yet been established. This paper describes the procedures for the in-vitro tests to validate the accuracy of the new indirect calorimeter, and defines the ranges for the parameters to be evaluated in each test to optimize the validation for clinical and research calorimetry measurements. Two in-vitro tests have been defined to validate the accuracy of the gas analyzers and the overall function of the new calorimeter. 1) Gas composition analysis allows validating the accuracy of O 2 and CO 2 analyzers. Reference gas of known O 2 (or CO 2 ) concentration is diluted by pure nitrogen gas to achieve predefined O 2 (or CO 2 ) concentration, to be measured by the indirect calorimeter. O 2 and CO 2 concentrations to be tested were determined according to their expected ranges of concentrations during calorimetry measurements. 2) Gas exchange simulator analysis validates O 2 consumption (VO 2 ) and CO 2 production (VCO 2 ) measurements. CO 2 gas injection into artificial breath gas provided by the mechanical ventilator simulates VCO 2 . Resulting dilution of O 2 concentration in the expiratory air is analyzed by the calorimeter as VO 2 . CO 2 gas of identical concentration to the fraction of inspired O 2 (FiO 2 ) is used to simulate identical VO 2 and VCO 2 . Indirect calorimetry results from publications were analyzed to determine the VO 2 and VCO 2 values to be tested for the validation. O 2 concentration in respiratory air is highest at inspiration, and can decrease to 15% during expiration. CO 2 concentration can be as high as 5% in expired air. To validate analyzers for measurements of FiO 2 up to 70%, ranges of O 2 and CO 2 concentrations to be tested were defined as 15-70% and 0.5-5.0%, respectively. The mean VO 2 in 426 adult mechanically ventilated patients was 270 ml/min, with 2 standard deviation (SD) ranges of 150-391 ml/min. Thus, VO 2 and VCO 2 to be simulated for the validation were defined as 150, 250, and 400 ml/min. The procedures for the in-vitro tests of the new indirect calorimeter and the ranges for the parameters to be evaluated in each test have been defined to optimize the validation of accuracy for clinical and research indirect calorimetry measurements. The combined methods will be used to validate the accuracy of the new indirect calorimeter developed by the ICALIC initiative, and should become the standard method to validate the accuracy of any future indirect calorimeters. Copyright © 2017 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

Statistical validation of normal tissue complication probability models.

PubMed

Xu, Cheng-Jian; van der Schaaf, Arjen; Van't Veld, Aart A; Langendijk, Johannes A; Schilstra, Cornelis

2012-09-01

To investigate the applicability and value of double cross-validation and permutation tests as established statistical approaches in the validation of normal tissue complication probability (NTCP) models. A penalized regression method, LASSO (least absolute shrinkage and selection operator), was used to build NTCP models for xerostomia after radiation therapy treatment of head-and-neck cancer. Model assessment was based on the likelihood function and the area under the receiver operating characteristic curve. Repeated double cross-validation showed the uncertainty and instability of the NTCP models and indicated that the statistical significance of model performance can be obtained by permutation testing. Repeated double cross-validation and permutation tests are recommended to validate NTCP models before clinical use. Copyright © 2012 Elsevier Inc. All rights reserved.

International ring trial for the validation of an event-specific Golden Rice 2 quantitative real-time polymerase chain reaction method.

PubMed

Jacchia, Sara; Nardini, Elena; Bassani, Niccolò; Savini, Christian; Shim, Jung-Hyun; Trijatmiko, Kurniawan; Kreysa, Joachim; Mazzara, Marco

2015-05-27

This article describes the international validation of the quantitative real-time polymerase chain reaction (PCR) detection method for Golden Rice 2. The method consists of a taxon-specific assay amplifying a fragment of rice Phospholipase D α2 gene, and an event-specific assay designed on the 3' junction between transgenic insert and plant DNA. We validated the two assays independently, with absolute quantification, and in combination, with relative quantification, on DNA samples prepared in haploid genome equivalents. We assessed trueness, precision, efficiency, and linearity of the two assays, and the results demonstrate that both the assays independently assessed and the entire method fulfill European and international requirements for methods for genetically modified organism (GMO) testing, within the dynamic range tested. The homogeneity of the results of the collaborative trial between Europe and Asia is a good indicator of the robustness of the method.

A wall interference assessment/correction system

NASA Technical Reports Server (NTRS)

Lo, Ching F.; Ulbrich, N.; Sickles, W. L.; Qian, Cathy X.

1992-01-01

A Wall Signature method, the Hackett method, has been selected to be adapted for the 12-ft Wind Tunnel wall interference assessment/correction (WIAC) system in the present phase. This method uses limited measurements of the static pressure at the wall, in conjunction with the solid wall boundary condition, to determine the strength and distribution of singularities representing the test article. The singularities are used in turn for estimating wall interferences at the model location. The Wall Signature method will be formulated for application to the unique geometry of the 12-ft Tunnel. The development and implementation of a working prototype will be completed, delivered and documented with a software manual. The WIAC code will be validated by conducting numerically simulated experiments rather than actual wind tunnel experiments. The simulations will be used to generate both free-air and confined wind-tunnel flow fields for each of the test articles over a range of test configurations. Specifically, the pressure signature at the test section wall will be computed for the tunnel case to provide the simulated 'measured' data. These data will serve as the input for the WIAC method-Wall Signature method. The performance of the WIAC method then may be evaluated by comparing the corrected parameters with those for the free-air simulation. Each set of wind tunnel/test article numerical simulations provides data to validate the WIAC method. A numerical wind tunnel test simulation is initiated to validate the WIAC methods developed in the project. In the present reported period, the blockage correction has been developed and implemented for a rectangular tunnel as well as the 12-ft Pressure Tunnel. An improved wall interference assessment and correction method for three-dimensional wind tunnel testing is presented in the appendix.

Contemporary Test Validity in Theory and Practice: A Primer for Discipline-Based Education Researchers.

PubMed

Reeves, Todd D; Marbach-Ad, Gili

2016-01-01

Most discipline-based education researchers (DBERs) were formally trained in the methods of scientific disciplines such as biology, chemistry, and physics, rather than social science disciplines such as psychology and education. As a result, DBERs may have never taken specific courses in the social science research methodology--either quantitative or qualitative--on which their scholarship often relies so heavily. One particular aspect of (quantitative) social science research that differs markedly from disciplines such as biology and chemistry is the instrumentation used to quantify phenomena. In response, this Research Methods essay offers a contemporary social science perspective on test validity and the validation process. The instructional piece explores the concepts of test validity, the validation process, validity evidence, and key threats to validity. The essay also includes an in-depth example of a validity argument and validation approach for a test of student argument analysis. In addition to DBERs, this essay should benefit practitioners (e.g., lab directors, faculty members) in the development, evaluation, and/or selection of instruments for their work assessing students or evaluating pedagogical innovations. © 2016 T. D. Reeves and G. Marbach-Ad. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Program to analyze aquifer test data and check for validity with the jacob method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Field, M.S.

1993-01-01

The Jacob straight-line method of aquifer analysis deals with the late-time data and small radius of the Theis type curve which plot as a straight line if the drawdown data are plotted on an arithmetic scale and the time data on a logarithmic (base 10) scale. Correct analysis with the Jacob method normally assumes that (1) the data lie on a straight line, (2) the value of the dimensionless time factor is less than 0.01, and (3) the site's hydrogeology conforms to the method's assumptions and limiting conditions. Items 1 and 2 are usually considered for the Jacob method, butmore » item 3 is often ignored, which can lead to incorrect calculations of aquifer parameters. A BASIC computer program was developed to analyze aquifer test data with the Jacob method to test the validity of its use. Aquifer test data are entered into the program and manipulated so that a slope and time intercept of the straight line drawn through the data (excluding early-time and late-time data) can be used to calculate transmissivity and storage coefficient. Late-time data are excluded to eliminate the effects of positive and negative boundaries. The time-drawdown data then are converted into dimensionless units to determine if the Jacob method's assumptions are valid for the hydrogeologic conditions under which the test was conducted.« less

Adaptation and Validation of the Tower of London Test of Planning and Problem Solving in People with Intellectual Disabilities

ERIC Educational Resources Information Center

Masson, J. D.; Dagnan, D.; Evans, J.

2010-01-01

Background: There is a need for validated, standardised tools for the assessment of executive functions in adults with intellectual disabilities (ID). This study examines the validity of a test of planning and problem solving (Tower of London) with adults with ID. Method: Participants completed an adapted version of the Tower of London (ToL) while…

Validation of the Seating and Mobility Script Concordance Test

ERIC Educational Resources Information Center

Cohen, Laura J.; Fitzgerald, Shirley G.; Lane, Suzanne; Boninger, Michael L.; Minkel, Jean; McCue, Michael

2009-01-01

The purpose of this study was to develop the scoring system for the Seating and Mobility Script Concordance Test (SMSCT), obtain and appraise internal and external structure evidence, and assess the validity of the SMSCT. The SMSCT purpose is to provide a method for testing knowledge of seating and mobility prescription. A sample of 106 therapists…

A New Method for Analyzing Content Validity Data Using Multidimensional Scaling

ERIC Educational Resources Information Center

Li, Xueming; Sireci, Stephen G.

2013-01-01

Validity evidence based on test content is of essential importance in educational testing. One source for such evidence is an alignment study, which helps evaluate the congruence between tested objectives and those specified in the curriculum. However, the results of an alignment study do not always sufficiently capture the degree to which a test…

Methodology for testing and validating knowledge bases

NASA Technical Reports Server (NTRS)

Krishnamurthy, C.; Padalkar, S.; Sztipanovits, J.; Purves, B. R.

1987-01-01

A test and validation toolset developed for artificial intelligence programs is described. The basic premises of this method are: (1) knowledge bases have a strongly declarative character and represent mostly structural information about different domains, (2) the conditions for integrity, consistency, and correctness can be transformed into structural properties of knowledge bases, and (3) structural information and structural properties can be uniformly represented by graphs and checked by graph algorithms. The interactive test and validation environment have been implemented on a SUN workstation.

A simple randomisation procedure for validating discriminant analysis: a methodological note.

PubMed

Wastell, D G

1987-04-01

Because the goal of discriminant analysis (DA) is to optimise classification, it designedly exaggerates between-group differences. This bias complicates validation of DA. Jack-knifing has been used for validation but is inappropriate when stepwise selection (SWDA) is employed. A simple randomisation test is presented which is shown to give correct decisions for SWDA. The general superiority of randomisation tests over orthodox significance tests is discussed. Current work on non-parametric methods of estimating the error rates of prediction rules is briefly reviewed.

Item Development and Validity Testing for a Self- and Proxy Report: The Safe Driving Behavior Measure

PubMed Central

Classen, Sherrilene; Winter, Sandra M.; Velozo, Craig A.; Bédard, Michel; Lanford, Desiree N.; Brumback, Babette; Lutz, Barbara J.

2010-01-01

OBJECTIVE We report on item development and validity testing of a self-report older adult safe driving behaviors measure (SDBM). METHOD On the basis of theoretical frameworks (Precede–Proceed Model of Health Promotion, Haddon’s matrix, and Michon’s model), existing driving measures, and previous research and guided by measurement theory, we developed items capturing safe driving behavior. Item development was further informed by focus groups. We established face validity using peer reviewers and content validity using expert raters. RESULTS Peer review indicated acceptable face validity. Initial expert rater review yielded a scale content validity index (CVI) rating of 0.78, with 44 of 60 items rated ≥0.75. Sixteen unacceptable items (≤0.5) required major revision or deletion. The next CVI scale average was 0.84, indicating acceptable content validity. CONCLUSION The SDBM has relevance as a self-report to rate older drivers. Future pilot testing of the SDBM comparing results with on-road testing will define criterion validity. PMID:20437917

Fuzzy-logic based strategy for validation of multiplex methods: example with qualitative GMO assays.

PubMed

Bellocchi, Gianni; Bertholet, Vincent; Hamels, Sandrine; Moens, W; Remacle, José; Van den Eede, Guy

2010-02-01

This paper illustrates the advantages that a fuzzy-based aggregation method could bring into the validation of a multiplex method for GMO detection (DualChip GMO kit, Eppendorf). Guidelines for validation of chemical, bio-chemical, pharmaceutical and genetic methods have been developed and ad hoc validation statistics are available and routinely used, for in-house and inter-laboratory testing, and decision-making. Fuzzy logic allows summarising the information obtained by independent validation statistics into one synthetic indicator of overall method performance. The microarray technology, introduced for simultaneous identification of multiple GMOs, poses specific validation issues (patterns of performance for a variety of GMOs at different concentrations). A fuzzy-based indicator for overall evaluation is illustrated in this paper, and applied to validation data for different genetically modified elements. Remarks were drawn on the analytical results. The fuzzy-logic based rules were shown to be applicable to improve interpretation of results and facilitate overall evaluation of the multiplex method.

Slip resistance of winter footwear on snow and ice measured using maximum achievable incline.

PubMed

Hsu, Jennifer; Shaw, Robert; Novak, Alison; Li, Yue; Ormerod, Marcus; Newton, Rita; Dutta, Tilak; Fernie, Geoff

2016-05-01

Protective footwear is necessary for preventing injurious slips and falls in winter conditions. Valid methods for assessing footwear slip resistance on winter surfaces are needed in order to evaluate footwear and outsole designs. The purpose of this study was to utilise a method of testing winter footwear that was ecologically valid in terms of involving actual human testers walking on realistic winter surfaces to produce objective measures of slip resistance. During the experiment, eight participants tested six styles of footwear on wet ice, on dry ice, and on dry ice after walking over soft snow. Slip resistance was measured by determining the maximum incline angles participants were able to walk up and down in each footwear-surface combination. The results indicated that testing on a variety of surfaces is necessary for establishing winter footwear performance and that standard mechanical bench tests for footwear slip resistance do not adequately reflect actual performance. Practitioner Summary: Existing standardised methods for measuring footwear slip resistance lack validation on winter surfaces. By determining the maximum inclines participants could walk up and down slopes of wet ice, dry ice, and ice with snow, in a range of footwear, an ecologically valid test for measuring winter footwear performance was established.

Slip resistance of winter footwear on snow and ice measured using maximum achievable incline

PubMed Central

Hsu, Jennifer; Shaw, Robert; Novak, Alison; Li, Yue; Ormerod, Marcus; Newton, Rita; Dutta, Tilak; Fernie, Geoff

2016-01-01

Abstract Protective footwear is necessary for preventing injurious slips and falls in winter conditions. Valid methods for assessing footwear slip resistance on winter surfaces are needed in order to evaluate footwear and outsole designs. The purpose of this study was to utilise a method of testing winter footwear that was ecologically valid in terms of involving actual human testers walking on realistic winter surfaces to produce objective measures of slip resistance. During the experiment, eight participants tested six styles of footwear on wet ice, on dry ice, and on dry ice after walking over soft snow. Slip resistance was measured by determining the maximum incline angles participants were able to walk up and down in each footwear–surface combination. The results indicated that testing on a variety of surfaces is necessary for establishing winter footwear performance and that standard mechanical bench tests for footwear slip resistance do not adequately reflect actual performance. Practitioner Summary: Existing standardised methods for measuring footwear slip resistance lack validation on winter surfaces. By determining the maximum inclines participants could walk up and down slopes of wet ice, dry ice, and ice with snow, in a range of footwear, an ecologically valid test for measuring winter footwear performance was established. PMID:26555738

Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests.

PubMed

Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

2015-09-01

The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%).

Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests

PubMed Central

Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

2014-01-01

The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%). PMID:27134543

Working towards accreditation by the International Standards Organization 15189 Standard: how to validate an in-house developed method an example of lead determination in whole blood by electrothermal atomic absorption spectrometry.

PubMed

Garcia Hejl, Carine; Ramirez, Jose Manuel; Vest, Philippe; Chianea, Denis; Renard, Christophe

2014-09-01

Laboratories working towards accreditation by the International Standards Organization (ISO) 15189 standard are required to demonstrate the validity of their analytical methods. The different guidelines set by various accreditation organizations make it difficult to provide objective evidence that an in-house method is fit for the intended purpose. Besides, the required performance characteristics tests and acceptance criteria are not always detailed. The laboratory must choose the most suitable validation protocol and set the acceptance criteria. Therefore, we propose a validation protocol to evaluate the performance of an in-house method. As an example, we validated the process for the detection and quantification of lead in whole blood by electrothermal absorption spectrometry. The fundamental parameters tested were, selectivity, calibration model, precision, accuracy (and uncertainty of measurement), contamination, stability of the sample, reference interval, and analytical interference. We have developed a protocol that has been applied successfully to quantify lead in whole blood by electrothermal atomic absorption spectrometry (ETAAS). In particular, our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics.

Validation of catchment models for predicting land-use and climate change impacts. 2. Case study for a Mediterranean catchment

NASA Astrophysics Data System (ADS)

Parkin, G.; O'Donnell, G.; Ewen, J.; Bathurst, J. C.; O'Connell, P. E.; Lavabre, J.

1996-02-01

Validation methods commonly used to test catchment models are not capable of demonstrating a model's fitness for making predictions for catchments where the catchment response is not known (including hypothetical catchments, and future conditions of existing catchments which are subject to land-use or climate change). This paper describes the first use of a new method of validation (Ewen and Parkin, 1996. J. Hydrol., 175: 583-594) designed to address these types of application; the method involves making 'blind' predictions of selected hydrological responses which are considered important for a particular application. SHETRAN (a physically based, distributed catchment modelling system) is tested on a small Mediterranean catchment. The test involves quantification of the uncertainty in four predicted features of the catchment response (continuous hydrograph, peak discharge rates, monthly runoff, and total runoff), and comparison of observations with the predicted ranges for these features. The results of this test are considered encouraging.

Experimental methods to validate measures of emotional state and readiness for duty in critical operations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weston, Louise Marie

2007-09-01

A recent report on criticality accidents in nuclear facilities indicates that human error played a major role in a significant number of incidents with serious consequences and that some of these human errors may be related to the emotional state of the individual. A pre-shift test to detect a deleterious emotional state could reduce the occurrence of such errors in critical operations. The effectiveness of pre-shift testing is a challenge because of the need to gather predictive data in a relatively short test period and the potential occurrence of learning effects due to a requirement for frequent testing. This reportmore » reviews the different types of reliability and validity methods and testing and statistical analysis procedures to validate measures of emotional state. The ultimate value of a validation study depends upon the percentage of human errors in critical operations that are due to the emotional state of the individual. A review of the literature to identify the most promising predictors of emotional state for this application is highly recommended.« less

A Retrospective Performance Assessment of the Developmental Neurotoxicity Study in Support of OECD Test Guideline 426

PubMed Central

Makris, Susan L.; Raffaele, Kathleen; Allen, Sandra; Bowers, Wayne J.; Hass, Ulla; Alleva, Enrico; Calamandrei, Gemma; Sheets, Larry; Amcoff, Patric; Delrue, Nathalie; Crofton, Kevin M.

2009-01-01

Objective We conducted a review of the history and performance of developmental neurotoxicity (DNT) testing in support of the finalization and implementation of Organisation of Economic Co-operation and Development (OECD) DNT test guideline 426 (TG 426). Information sources and analysis In this review we summarize extensive scientific efforts that form the foundation for this testing paradigm, including basic neurotoxicology research, interlaboratory collaborative studies, expert workshops, and validation studies, and we address the relevance, applicability, and use of the DNT study in risk assessment. Conclusions The OECD DNT guideline represents the best available science for assessing the potential for DNT in human health risk assessment, and data generated with this protocol are relevant and reliable for the assessment of these end points. The test methods used have been subjected to an extensive history of international validation, peer review, and evaluation, which is contained in the public record. The reproducibility, reliability, and sensitivity of these methods have been demonstrated, using a wide variety of test substances, in accordance with OECD guidance on the validation and international acceptance of new or updated test methods for hazard characterization. Multiple independent, expert scientific peer reviews affirm these conclusions. PMID:19165382

Performance Validity Testing in Neuropsychology: Scientific Basis and Clinical Application-A Brief Review.

PubMed

Greher, Michael R; Wodushek, Thomas R

2017-03-01

Performance validity testing refers to neuropsychologists' methodology for determining whether neuropsychological test performances completed in the course of an evaluation are valid (ie, the results of true neurocognitive function) or invalid (ie, overly impacted by the patient's effort/engagement in testing). This determination relies upon the use of either standalone tests designed for this sole purpose, or specific scores/indicators embedded within traditional neuropsychological measures that have demonstrated this utility. In response to a greater appreciation for the critical role that performance validity issues play in neuropsychological testing and the need to measure this variable to the best of our ability, the scientific base for performance validity testing has expanded greatly over the last 20 to 30 years. As such, the majority of current day neuropsychologists in the United States use a variety of measures for the purpose of performance validity testing as part of everyday forensic and clinical practice and address this issue directly in their evaluations. The following is the first article of a 2-part series that will address the evolution of performance validity testing in the field of neuropsychology, both in terms of the science as well as the clinical application of this measurement technique. The second article of this series will review performance validity tests in terms of methods for development of these measures, and maximizing of diagnostic accuracy.

Formal verification and testing: An integrated approach to validating Ada programs

NASA Technical Reports Server (NTRS)

Cohen, Norman H.

1986-01-01

An integrated set of tools called a validation environment is proposed to support the validation of Ada programs by a combination of methods. A Modular Ada Validation Environment (MAVEN) is described which proposes a context in which formal verification can fit into the industrial development of Ada software.

Comparison of on-site field measured inorganic arsenic in rice with laboratory measurements using a field deployable method: Method validation.

PubMed

Mlangeni, Angstone Thembachako; Vecchi, Valeria; Norton, Gareth J; Raab, Andrea; Krupp, Eva M; Feldmann, Joerg

2018-10-15

A commercial arsenic field kit designed to measure inorganic arsenic (iAs) in water was modified into a field deployable method (FDM) to measure iAs in rice. While the method has been validated to give precise and accurate results in the laboratory, its on-site field performance has not been evaluated. This study was designed to test the method on-site in Malawi in order to evaluate its accuracy and precision in determination of iAs on-site by comparing with a validated reference method and giving original data on inorganic arsenic in Malawian rice and rice-based products. The method was validated by using the established laboratory-based HPLC-ICPMS. Statistical tests indicated there were no significant differences between on-site and laboratory iAs measurements determined using the FDM (p = 0.263, ά = 0.05) and between on-site measurements and measurements determined using HPLC-ICP-MS (p = 0.299, ά = 0.05). This method allows quick (within 1 h) and efficient screening of rice containing iAs concentrations on-site. Copyright © 2018 Elsevier Ltd. All rights reserved.

Establishing survey validity and reliability for American Indians through "think aloud" and test-retest methods.

PubMed

Hauge, Cindy Horst; Jacobs-Knight, Jacque; Jensen, Jamie L; Burgess, Katherine M; Puumala, Susan E; Wilton, Georgiana; Hanson, Jessica D

2015-06-01

The purpose of this study was to use a mixed-methods approach to determine the validity and reliability of measurements used within an alcohol-exposed pregnancy prevention program for American Indian women. To develop validity, content experts provided input into the survey measures, and a "think aloud" methodology was conducted with 23 American Indian women. After revising the measurements based on this input, a test-retest was conducted with 79 American Indian women who were randomized to complete either the original measurements or the new, modified measurements. The test-retest revealed that some of the questions performed better for the modified version, whereas others appeared to be more reliable for the original version. The mixed-methods approach was a useful methodology for gathering feedback on survey measurements from American Indian participants and in indicating specific survey questions that needed to be modified for this population. © The Author(s) 2015.

Validation of an HPLC method for the quantification of ambroxol hydrochloride and benzoic acid in a syrup as pharmaceutical form stress test for stability evaluation.

PubMed

Heinänen, M; Barbas, C

2001-03-01

A method is described for ambroxol, trans-4-(2-amino-3,5-dibromobenzylamino) cyclohexanol hydrochloride, and benzoic acid separation by HPLC with UV detection at 247 nm in a syrup as pharmaceutical presentation. Optimal conditions were: Column Symmetry Shield RPC8, 5 microm 250 x 4.6 mm, and methanol/(H(3)PO(4) 8.5 mM/triethylamine pH=2.8) 40:60 v/v. Validation was performed using standards and the pharmaceutical preparation which contains the compounds described above. Results from both standards and samples show suitable validation parameters. The pharmaceutical grade substances were tested by factors that could influence the chemical stability. These reaction mixtures were analysed to evaluate the capability of the method to separate degradation products. Degradation products did not interfere with the determination of the substances tested by the assay.

THE MURINE LOCAL LYMPH NODE ASSAY: AN ALTERNATIVE TEST METHOD FOR THE EVALUATION OF THE POTENTIAL FOR CHEMICALS TO ELICIT ALLERGIC CONTACT DERMATITIS

EPA Science Inventory

ABSTRACT
The process that a new toxicology test method must undergo to attain acceptance and regulatory implementation may seem daunting. As the first test method to undergo Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) review, the local...

Testing the feasibility of eliciting preferences for health states from adolescents using direct methods.

PubMed

Crump, R Trafford; Lau, Ryan; Cox, Elizabeth; Currie, Gillian; Panepinto, Julie

2018-06-22

Measuring adolescents' preferences for health states can play an important role in evaluating the delivery of pediatric healthcare. However, formal evaluation of the common direct preference elicitation methods for health states has not been done with adolescents. Therefore, the purpose of this study is to test how these methods perform in terms of their feasibility, reliability, and validity for measuring health state preferences in adolescents. This study used a web-based survey of adolescents, 18 years of age or younger, living in the United States. The survey included four health states, each comprised of six attributes. Preferences for these health states were elicited using the visual analogue scale, time trade-off, and standard gamble. The feasibility, test-retest reliability, and construct validity of each of these preference elicitation methods were tested and compared. A total of 144 participants were included in this study. Using a web-based survey format to elicit preferences for health states from adolescents was feasible. A majority of participants completed all three elicitation methods, ranked those methods as being easy, with very few requiring assistance from someone else. However, all three elicitation methods demonstrated weak test-retest reliability, with Kendall's tau-a values ranging from 0.204 to 0.402. Similarly, all three methods demonstrated poor construct validity, with 9-50% of all rankings aligning with our expectations. There were no significant differences across age groups. Using a web-based survey format to elicit preferences for health states from adolescents is feasible. However, the reliability and construct validity of the methods used to elicit these preferences when using this survey format are poor. Further research into the effects of a web-based survey approach to eliciting preferences for health states from adolescents is needed before health services researchers or pediatric clinicians widely employ these methods.

CAPTIONALS: A computer aided testing environment for the verification and validation of communication protocols

NASA Technical Reports Server (NTRS)

Feng, C.; Sun, X.; Shen, Y. N.; Lombardi, Fabrizio

1992-01-01

This paper covers the verification and protocol validation for distributed computer and communication systems using a computer aided testing approach. Validation and verification make up the so-called process of conformance testing. Protocol applications which pass conformance testing are then checked to see whether they can operate together. This is referred to as interoperability testing. A new comprehensive approach to protocol testing is presented which address: (1) modeling for inter-layer representation for compatibility between conformance and interoperability testing; (2) computational improvement to current testing methods by using the proposed model inclusive of formulation of new qualitative and quantitative measures and time-dependent behavior; (3) analysis and evaluation of protocol behavior for interactive testing without extensive simulation.

QUANTITATIVE CANCER RISK ASSESSMENT METHODOLOGY USING SHORT-TERM GENETIC BIOASSAYS: THE COMPARATIVE POTENCY METHOD

EPA Science Inventory

Quantitative risk assessment is fraught with many uncertainties. The validity of the assumptions underlying the methods employed are often difficult to test or validate. Cancer risk assessment has generally employed either human epidemiological data from relatively high occupatio...

What Do You Think You Are Measuring? A Mixed-Methods Procedure for Assessing the Content Validity of Test Items and Theory-Based Scaling

PubMed Central

Koller, Ingrid; Levenson, Michael R.; Glück, Judith

2017-01-01

The valid measurement of latent constructs is crucial for psychological research. Here, we present a mixed-methods procedure for improving the precision of construct definitions, determining the content validity of items, evaluating the representativeness of items for the target construct, generating test items, and analyzing items on a theoretical basis. To illustrate the mixed-methods content-scaling-structure (CSS) procedure, we analyze the Adult Self-Transcendence Inventory, a self-report measure of wisdom (ASTI, Levenson et al., 2005). A content-validity analysis of the ASTI items was used as the basis of psychometric analyses using multidimensional item response models (N = 1215). We found that the new procedure produced important suggestions concerning five subdimensions of the ASTI that were not identifiable using exploratory methods. The study shows that the application of the suggested procedure leads to a deeper understanding of latent constructs. It also demonstrates the advantages of theory-based item analysis. PMID:28270777

Assessing Discriminative Performance at External Validation of Clinical Prediction Models

PubMed Central

Nieboer, Daan; van der Ploeg, Tjeerd; Steyerberg, Ewout W.

2016-01-01

Introduction External validation studies are essential to study the generalizability of prediction models. Recently a permutation test, focusing on discrimination as quantified by the c-statistic, was proposed to judge whether a prediction model is transportable to a new setting. We aimed to evaluate this test and compare it to previously proposed procedures to judge any changes in c-statistic from development to external validation setting. Methods We compared the use of the permutation test to the use of benchmark values of the c-statistic following from a previously proposed framework to judge transportability of a prediction model. In a simulation study we developed a prediction model with logistic regression on a development set and validated them in the validation set. We concentrated on two scenarios: 1) the case-mix was more heterogeneous and predictor effects were weaker in the validation set compared to the development set, and 2) the case-mix was less heterogeneous in the validation set and predictor effects were identical in the validation and development set. Furthermore we illustrated the methods in a case study using 15 datasets of patients suffering from traumatic brain injury. Results The permutation test indicated that the validation and development set were homogenous in scenario 1 (in almost all simulated samples) and heterogeneous in scenario 2 (in 17%-39% of simulated samples). Previously proposed benchmark values of the c-statistic and the standard deviation of the linear predictors correctly pointed at the more heterogeneous case-mix in scenario 1 and the less heterogeneous case-mix in scenario 2. Conclusion The recently proposed permutation test may provide misleading results when externally validating prediction models in the presence of case-mix differences between the development and validation population. To correctly interpret the c-statistic found at external validation it is crucial to disentangle case-mix differences from incorrect regression coefficients. PMID:26881753

Experimental Investigation of Textile Composite Materials Using Moire Interferometry

NASA Technical Reports Server (NTRS)

Ifju, Peter G.

1995-01-01

The viability as an efficient aircraft material of advanced textile composites is currently being addressed in the NASA Advanced Composites Technology (ACT) Program. One of the expected milestones of the program is to develop standard test methods for these complex material systems. Current test methods for laminated composites may not be optimum for textile composites, since the architecture of the textile induces nonuniform deformation characteristics on the scale of the smallest repeating unit of the architecture. The smallest repeating unit, also called the unit cell, is often larger than the strain gages used for testing of tape composites. As a result, extending laminated composite test practices to textiles can often lead to pronounced scatter in material property measurements. It has been speculated that the fiber architectures produce significant surface strain nonuniformities, however, the magnitudes were not well understood. Moire interferometry, characterized by full-field information, high displacement sensitivity, and high spatial resolution, is well suited to document the surface strain on textile composites. Studies at the NASA Langley Research Center on a variety of textile architectures including 2-D braids and 3-D weaves, has evidenced the merits of using moire interferometry to guide in test method development for textile composites. Moire was used to support tensile testing by validating instrumentation practices and documenting damage mechanisms. It was used to validate shear test methods by mapping the full-field deformation of shear specimens. Moire was used to validate open hole tension experiments to determine the strain concentration and compare then to numeric predictions. It was used for through-the-thickness tensile strength test method development, to verify capabilities for testing of both 2-D and 3-D material systems. For all of these examples, moire interferometry provided vision so that test methods could be developed with less speculation and more documentation.

History and development of the Schmidt-Hunter meta-analysis methods.

PubMed

Schmidt, Frank L

2015-09-01

In this article, I provide answers to the questions posed by Will Shadish about the history and development of the Schmidt-Hunter methods of meta-analysis. In the 1970s, I headed a research program on personnel selection at the US Office of Personnel Management (OPM). After our research showed that validity studies have low statistical power, OPM felt a need for a better way to demonstrate test validity, especially in light of court cases challenging selection methods. In response, we created our method of meta-analysis (initially called validity generalization). Results showed that most of the variability of validity estimates from study to study was because of sampling error and other research artifacts such as variations in range restriction and measurement error. Corrections for these artifacts in our research and in replications by others showed that the predictive validity of most tests was high and generalizable. This conclusion challenged long-standing beliefs and so provoked resistance, which over time was overcome. The 1982 book that we published extending these methods to research areas beyond personnel selection was positively received and was followed by expanded books in 1990, 2004, and 2014. Today, these methods are being applied in a wide variety of areas. Copyright © 2015 John Wiley & Sons, Ltd.

Evaluating the statistical performance of less applied algorithms in classification of worldview-3 imagery data in an urbanized landscape

NASA Astrophysics Data System (ADS)

Ranaie, Mehrdad; Soffianian, Alireza; Pourmanafi, Saeid; Mirghaffari, Noorollah; Tarkesh, Mostafa

2018-03-01

In recent decade, analyzing the remotely sensed imagery is considered as one of the most common and widely used procedures in the environmental studies. In this case, supervised image classification techniques play a central role. Hence, taking a high resolution Worldview-3 over a mixed urbanized landscape in Iran, three less applied image classification methods including Bagged CART, Stochastic gradient boosting model and Neural network with feature extraction were tested and compared with two prevalent methods: random forest and support vector machine with linear kernel. To do so, each method was run ten time and three validation techniques was used to estimate the accuracy statistics consist of cross validation, independent validation and validation with total of train data. Moreover, using ANOVA and Tukey test, statistical difference significance between the classification methods was significantly surveyed. In general, the results showed that random forest with marginal difference compared to Bagged CART and stochastic gradient boosting model is the best performing method whilst based on independent validation there was no significant difference between the performances of classification methods. It should be finally noted that neural network with feature extraction and linear support vector machine had better processing speed than other.

SDG and qualitative trend based model multiple scale validation

NASA Astrophysics Data System (ADS)

Gao, Dong; Xu, Xin; Yin, Jianjin; Zhang, Hongyu; Zhang, Beike

2017-09-01

Verification, Validation and Accreditation (VV&A) is key technology of simulation and modelling. For the traditional model validation methods, the completeness is weak; it is carried out in one scale; it depends on human experience. The SDG (Signed Directed Graph) and qualitative trend based multiple scale validation is proposed. First the SDG model is built and qualitative trends are added to the model. And then complete testing scenarios are produced by positive inference. The multiple scale validation is carried out by comparing the testing scenarios with outputs of simulation model in different scales. Finally, the effectiveness is proved by carrying out validation for a reactor model.

Toward Validation of Tests for Teachers in Spanish/English Bilingual Education Programs. Research and Development Memorandum No. 151.

ERIC Educational Resources Information Center

Merino, Barbara J.; Politzer, Robert L.

This memorandum reports the validation of the SCRDT Tests for Teachers in Spanish/English Bilingual Education Programs. The tests, which are designed for elementary and secondary teachers and aides, measure knowledge of methods used in teaching English as a second language (ESL), teaching Spanish as a second language (SSL), and teaching reading in…

16 CFR 1500.41 - Method of testing primary irritant substances.

Code of Federal Regulations, 2014 CFR

2014-01-01

... corrosivity properties of substances, including testing that does not require animals, are presented in the CPSC's animal testing policy set forth in 16 CFR 1500.232. A weight-of-evidence analysis or a validated... conducted, a sequential testing strategy is recommended to reduce the number of test animals. The method of...

Simulation verification techniques study: Simulation performance validation techniques document. [for the space shuttle system

NASA Technical Reports Server (NTRS)

Duncan, L. M.; Reddell, J. P.; Schoonmaker, P. B.

1975-01-01

Techniques and support software for the efficient performance of simulation validation are discussed. Overall validation software structure, the performance of validation at various levels of simulation integration, guidelines for check case formulation, methods for real time acquisition and formatting of data from an all up operational simulator, and methods and criteria for comparison and evaluation of simulation data are included. Vehicle subsystems modules, module integration, special test requirements, and reference data formats are also described.

75 FR 57027 - National Toxicology Program (NTP); NTP Interagency Center for the Evaluation of Alternative...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-17

... for the Evaluation of Alternative Toxicological Methods (NICEATM); Availability of Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) Test Method Evaluation Reports: In Vitro Ocular Safety Testing Methods and Strategies, and Routine Use of Topical Anesthetics, Systemic...

[Visualisation methods for etheric formative forces].

PubMed

Burkhard, B; Kittel, R

2009-09-01

Rudolf Steiner, the founder of anthroposophy, suggested the development of visualisation methods for "etheric formative forces". The essential methods, their "spiritual scientific" basis and indications are described and their claims critically tested. The methods are not validated, the key criteria for diagnostic tests (reproducibility, sensitivity, specifity) are not given.

Towards Validation of an Adaptive Flight Control Simulation Using Statistical Emulation

NASA Technical Reports Server (NTRS)

He, Yuning; Lee, Herbert K. H.; Davies, Misty D.

2012-01-01

Traditional validation of flight control systems is based primarily upon empirical testing. Empirical testing is sufficient for simple systems in which a.) the behavior is approximately linear and b.) humans are in-the-loop and responsible for off-nominal flight regimes. A different possible concept of operation is to use adaptive flight control systems with online learning neural networks (OLNNs) in combination with a human pilot for off-nominal flight behavior (such as when a plane has been damaged). Validating these systems is difficult because the controller is changing during the flight in a nonlinear way, and because the pilot and the control system have the potential to co-adapt in adverse ways traditional empirical methods are unlikely to provide any guarantees in this case. Additionally, the time it takes to find unsafe regions within the flight envelope using empirical testing means that the time between adaptive controller design iterations is large. This paper describes a new concept for validating adaptive control systems using methods based on Bayesian statistics. This validation framework allows the analyst to build nonlinear models with modal behavior, and to have an uncertainty estimate for the difference between the behaviors of the model and system under test.

Validation of Screening Assays for Developmental Toxicity: An Exposure-Based Approach

EPA Science Inventory

There continue to be widespread efforts to develop assay methods for developmental toxicity that are shorter than the traditional Segment 2 study and use fewer or no animals. As with any alternative test method, novel developmental toxicity assays must be validated by evaluating ...

Development and Validation of New Discriminative Dissolution Method for Carvedilol Tablets

PubMed Central

Raju, V.; Murthy, K. V. R.

2011-01-01

The objective of the present study was to develop and validate a discriminative dissolution method for evaluation of carvedilol tablets. Different conditions such as type of dissolution medium, volume of dissolution medium and rotation speed of paddle were evaluated. The best in vitro dissolution profile was obtained using Apparatus II (paddle), 50 rpm, 900 ml of pH 6.8 phosphate buffer as dissolution medium. The drug release was evaluated by high-performance liquid chromatographic method. The dissolution method was validated according to current ICH and FDA guidelines using parameters such as the specificity, accuracy, precision and stability were evaluated and obtained results were within the acceptable range. The comparison of the obtained dissolution profiles of three different products were investigated using ANOVA-based, model-dependent and model-independent methods, results showed that there is significant difference between the products. The dissolution test developed and validated was adequate for its higher discriminative capacity in differentiating the release characteristics of the products tested and could be applied for development and quality control of carvedilol tablets. PMID:22923865

SAS molecular tests Salmonella detection kit. Performance tested method 021202.

PubMed

Bapanpally, Chandra; Montier, Laura; Khan, Shah; Kasra, Akif; Brunelle, Sharon L

2014-01-01

The SAS Molecular tests Salmonella Detection method, a Loop-mediated Isothermal Amplification method, performed as well as or better than the U.S. Department of Agriculture-Food Safety Inspection Service Microbiology Laboratory Guidebook and the U.S. Food and Drug Administration Bacteriological Analytical Manual reference methods for ground beef, beef trim, ground turkey, chicken carcass rinses, bagged mixed lettuce, and fresh spinach. The ground beef (30% fat, 25 g test portion), poultry matrixes and leafy greens were validated in a 6-7 h enrichment, and ground beef (30% fat, 375 g composite test portion) and beef trim (375 g composite test portion) were validated in a 16-20 h enrichment. The method performance for meat and leafy green matrixes was shown to be acceptable under conditions of co-enrichment with Escherichia coli 0157. Thus, after a short 6-7 h co-enrichment step, ground beef, beef trim, lettuce, and spinach can be tested for both Salmonella and E. coli O157. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 100 Salmonella serovars and 30 non-Salmonella species examined. The method was shown to be robust when enrichment time, DNA extract hold time, and DNA volume were varied.

Evaluation of the Thermo Scientific SureTect Salmonella species assay. AOAC Performance Tested Method 051303.

PubMed

Cloke, Jonathan; Clark, Dorn; Radcliff, Roy; Leon-Velarde, Carlos; Larson, Nathan; Dave, Keron; Evans, Katharine; Crabtree, David; Hughes, Annette; Simpson, Helen; Holopainen, Jani; Wickstrand, Nina; Kauppinen, Mikko

2014-01-01

The Thermo Scientific SureTect Salmonella species Assay is a new real-time PCR assay for the detection of Salmonellae in food and environmental samples. This validation study was conducted using the AOAC Research Institute (RI) Performance Tested Methods program to validate the SureTect Salmonella species Assay in comparison to the reference method detailed in International Organization for Standardization 6579:2002 in a variety of food matrixes, namely, raw ground beef, raw chicken breast, raw ground pork, fresh bagged lettuce, pork frankfurters, nonfat dried milk powder, cooked peeled shrimp, pasteurized liquid whole egg, ready-to-eat meal containing beef, and stainless steel surface samples. With the exception of liquid whole egg and fresh bagged lettuce, which were tested in-house, all matrixes were tested by Marshfield Food Safety, Marshfield, WI, on behalf of Thermo Fisher Scientific. In addition, three matrixes (pork frankfurters, lettuce, and stainless steel surface samples) were analyzed independently as part of the AOAC-RI-controlled laboratory study by the University of Guelph, Canada. No significant difference by probability of detection or McNemars Chi-squared statistical analysis was found between the candidate or reference methods for any of the food matrixes or environmental surface samples tested during the validation study. Inclusivity and exclusivity testing was conducted with 117 and 36 isolates, respectively, which demonstrated that the SureTect Salmonella species Assay was able to detect all the major groups of Salmonella enterica subspecies enterica (e.g., Typhimurium) and the less common subspecies of S. enterica (e.g., arizoniae) and the rarely encountered S. bongori. None of the exclusivity isolates analyzed were detected by the SureTect Salmonella species Assay. Ruggedness testing was conducted to evaluate the performance of the assay with specific method deviations outside of the recommended parameters open to variation (enrichment time and temperature, and lysis temperature), which demonstrated that the assay gave reliable performance. Accelerated stability testing was additionally conducted, validating the assay shelf life.

Testing and Validation of the Dynamic Inertia Measurement Method

NASA Technical Reports Server (NTRS)

Chin, Alexander W.; Herrera, Claudia Y.; Spivey, Natalie D.; Fladung, William A.; Cloutier, David

2015-01-01

The Dynamic Inertia Measurement (DIM) method uses a ground vibration test setup to determine the mass properties of an object using information from frequency response functions. Most conventional mass properties testing involves using spin tables or pendulum-based swing tests, which for large aerospace vehicles becomes increasingly difficult and time-consuming, and therefore expensive, to perform. The DIM method has been validated on small test articles but has not been successfully proven on large aerospace vehicles. In response, the National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California) conducted mass properties testing on an "iron bird" test article that is comparable in mass and scale to a fighter-type aircraft. The simple two-I-beam design of the "iron bird" was selected to ensure accurate analytical mass properties. Traditional swing testing was also performed to compare the level of effort, amount of resources, and quality of data with the DIM method. The DIM test showed favorable results for the center of gravity and moments of inertia; however, the products of inertia showed disagreement with analytical predictions.

Translation, Cultural Adaptation and Validation of the Simple Shoulder Test to Spanish

PubMed Central

Arcuri, Francisco; Barclay, Fernando; Nacul, Ivan

2015-01-01

Background: The validation of widely used scales facilitates the comparison across international patient samples. Objective: The objective was to translate, culturally adapt and validate the Simple Shoulder Test into Argentinian Spanish. Methods: The Simple Shoulder Test was translated from English into Argentinian Spanish by two independent translators, translated back into English and evaluated for accuracy by an expert committee to correct the possible discrepancies. It was then administered to 50 patients with different shoulder conditions.Psycometric properties were analyzed including internal consistency, measured with Cronbach´s Alpha, test-retest reliability at 15 days with the interclass correlation coefficient. Results: The internal consistency, validation, was an Alpha of 0,808, evaluated as good. The test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.835, evaluated as excellent. Conclusion: The Simple Shoulder Test translation and it´s cultural adaptation to Argentinian-Spanish demonstrated adequate internal reliability and validity, ultimately allowing for its use in the comparison with international patient samples.

Validation of the Simple Shoulder Test in a Portuguese-Brazilian Population. Is the Latent Variable Structure and Validation of the Simple Shoulder Test Stable across Cultures?

PubMed Central

Neto, Jose Osni Bruggemann; Gesser, Rafael Lehmkuhl; Steglich, Valdir; Bonilauri Ferreira, Ana Paula; Gandhi, Mihir; Vissoci, João Ricardo Nickenig; Pietrobon, Ricardo

2013-01-01

Background The validation of widely used scales facilitates the comparison across international patient samples. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Objective The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Methods The Simple Shoulder Test was translated from English into Brazilian Portuguese, translated back into English, and evaluated for accuracy by an expert committee. It was then administered to 100 patients with shoulder conditions. Psychometric properties were analyzed including factor analysis, internal reliability, test-retest reliability at seven days, and construct validity in relation to the Short Form 36 health survey (SF-36). Results Factor analysis demonstrated a three factor solution. Cronbach’s alpha was 0.82. Test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.84. Associations were observed in the hypothesized direction with all subscales of SF-36 questionnaire. Conclusion The Simple Shoulder Test translation and cultural adaptation to Brazilian-Portuguese demonstrated adequate factor structure, internal reliability, and validity, ultimately allowing for its use in the comparison with international patient samples. PMID:23675436

Reliability and Validity of the Computerized Revised Token Test: Comparison of Reading and Listening Versions in Persons with and without Aphasia

ERIC Educational Resources Information Center

McNeil, Malcolm R.; Pratt, Sheila R.; Szuminsky, Neil; Sung, Jee Eun; Fossett, Tepanta R. D.; Fassbinder, Wiltrud; Lim, Kyoung Yuel

2015-01-01

Purpose: This study assessed the reliability and validity of intermodality associations and differences in persons with aphasia (PWA) and healthy controls (HC) on a computerized listening and 3 reading versions of the Revised Token Test (RTT; McNeil & Prescott, 1978). Method: Thirty PWA and 30 HC completed the test versions, including a…

The Six-Minute Walk Test for Adults with Intellectual Disability: A Study of Validity and Reliability

ERIC Educational Resources Information Center

Nasuti, Gabriella; Stuart-Hill, Lynneth; Temple, Viviene A.

2013-01-01

Background: The Six-Minute Walk Test (6MWT) has been used with clinical and healthy populations to assess functional capacity and cardiovascular fitness. The aim of this study was to determine the test-retest reliability of a modified-6MWT as well as concurrent validity of walk distance with peak oxygen uptake (VO[subscript 2] peak). Method:…

Interlaboratory study of a liquid chromatography method for erythromycin: determination of uncertainty.

PubMed

Dehouck, P; Vander Heyden, Y; Smeyers-Verbeke, J; Massart, D L; Marini, R D; Chiap, P; Hubert, Ph; Crommen, J; Van de Wauw, W; De Beer, J; Cox, R; Mathieu, G; Reepmeyer, J C; Voigt, B; Estevenon, O; Nicolas, A; Van Schepdael, A; Adams, E; Hoogmartens, J

2003-08-22

Erythromycin is a mixture of macrolide antibiotics produced by Saccharopolyspora erythreas during fermentation. A new method for the analysis of erythromycin by liquid chromatography has previously been developed. It makes use of an Astec C18 polymeric column. After validation in one laboratory, the method was now validated in an interlaboratory study. Validation studies are commonly used to test the fitness of the analytical method prior to its use for routine quality testing. The data derived in the interlaboratory study can be used to make an uncertainty statement as well. The relationship between validation and uncertainty statement is not clear for many analysts and there is a need to show how the existing data, derived during validation, can be used in practice. Eight laboratories participated in this interlaboratory study. The set-up allowed the determination of the repeatability variance, s(2)r and the between-laboratory variance, s(2)L. Combination of s(2)r and s(2)L results in the reproducibility variance s(2)R. It has been shown how these data can be used in future by a single laboratory that wants to make an uncertainty statement concerning the same analysis.

Development, Construction, and Content Validation of a Questionnaire to Test Mobile Shower Commode Usability

PubMed Central

Theodoros, Deborah G.; Russell, Trevor G.

2015-01-01

Background: Usability is an emerging domain of outcomes measurement in assistive technology provision. Currently, no questionnaires exist to test the usability of mobile shower commodes (MSCs) used by adults with spinal cord injury (SCI). Objective: To describe the development, construction, and initial content validation of an electronic questionnaire to test mobile shower commode usability for this population. Methods: The questionnaire was constructed using a mixed-methods approach in 5 phases: determining user preferences for the questionnaire’s format, developing an item bank of usability indicators from the literature and judgement of experts, constructing a preliminary questionnaire, assessing content validity with a panel of experts, and constructing the final questionnaire. Results: The electronic Mobile Shower Commode Assessment Tool Version 1.0 (eMAST 1.0) questionnaire tests MSC features and performance during activities identified using a mixed-methods approach and in consultation with users. It confirms that usability is complex and multidimensional. The final questionnaire contains 25 questions in 3 sections. The eMAST 1.0 demonstrates excellent content validity as determined by a small sample of expert clinicians. Conclusion: The eMAST 1.0 tests usability of MSCs from the perspective of adults with SCI and may be used to solicit feedback during MSC design, assessment, prescription, and ongoing use. Further studies assessing the eMAST’s psychometric properties, including studies with users of MSCs, are needed. PMID:25762862

[Method validation according to ISO 15189 and SH GTA 04: application for the detection of KRAS mutations using PCR TaqMan assay].

PubMed

Harlé, Alexandre; Dubois, Cindy; Rouyer, Marie; Merlin, Jean-Louis

2013-01-01

Since January 16(th) 2010, the French legislation requires that the medical laboratories must be accredited according to ISO 15189 standards. Thus, all medical laboratories in France must be accredited for at least part of their biological tests before the end of October 2013. Molecular biology tests are also concerned by the accreditation. Validation of molecular biology methods is made difficult, for reasons related to the methods, but also by the type of analytes that are basically rare. This article describes the validation of the qualitative detection of KRAS mutations in metastatic colorectal cancer using TaqMan PCR according to ISO 15189 and to the technical guide for accreditation in Human Health, SH-GTA-04, edited by the COFRAC.

Validation of Self-Report on Smoking among University Students in Korea

ERIC Educational Resources Information Center

Lee, Chung Yul; Shin, Sunmi; Lee, Hyeon Kyeong; Hong, Yoon Mi

2009-01-01

Objective: To validate the self-reported smoking status of Korean university students. Methods: Subjects included 322 Korean university in Korea, who participated in an annual health screening. Data on smoking were collected through a self-reported questionnaire and urine test. The data were analyzed by the McNemar test. Results: In the…

Validating the Posttraumatic Stress Disorder Symptom Scale with Persons Who Have Severe Mental Illnesses

ERIC Educational Resources Information Center

O'Hare, Thomas; Shen, Ce; Sherrer, Margaret

2007-01-01

Objective: Interview data collected from 275 clients with severe mental illnesses are used to test the construct and criterion validity of the Posttraumatic Stress Disorder Symptom Scale (PSS). Method: First, exploratory and confirmatory factor analyses are used to test whether the scale reflects the posttraumatic stress disorder (PTSD) symptom…

Initial Development and Validation of the BullyHARM: The Bullying, Harassment, and Aggression Receipt Measure

ERIC Educational Resources Information Center

Hall, William J.

2016-01-01

This article describes the development and preliminary validation of the Bullying, Harassment, and Aggression Receipt Measure (BullyHARM). The development of the BullyHARM involved a number of steps and methods, including a literature review, expert review, cognitive testing, readability testing, data collection from a large sample, reliability…

Reliability and Validity Testing of the Physical Resilience Measure

ERIC Educational Resources Information Center

Resnick, Barbara; Galik, Elizabeth; Dorsey, Susan; Scheve, Ann; Gutkin, Susan

2011-01-01

Objective: The purpose of this study was to test reliability and validity of the Physical Resilience Scale. Methods: A single-group repeated measure design was used and 130 older adults from three different housing sites participated. Participants completed the Physical Resilience Scale, Hardy-Gill Resilience Scale, 14-item Resilience Scale,…

Validation Study on a Rapid Method for Simultaneous Determination of Pesticide Residues in Vegetables and Fruits by LC-MS/MS.

PubMed

Sato, Tamaki; Miyamoto, Iori; Uemura, Masako; Nakatani, Tadashi; Kakutani, Naoya; Yamano, Tetsuo

2016-01-01

A validation study was carried out on a rapid method for the simultaneous determination of pesticide residues in vegetables and fruits by LC-MS/MS. Preparation of the test solution was performed by a solid-phase extraction technique with QuEChERS (STQ method). Pesticide residues were extracted with acetonitrile using a homogenizer, followed by salting-out and dehydration at the same time. The acetonitrile layer was purified with C18 and PSA mini-columns. The method was assessed for 130 pesticide residues in 14 kinds of vegetables and fruits at the concentration level of 0.01 μg/g according to the method validation guideline of the Ministry of Health, Labour and Welfare of Japan. As a result 75 to 120 pesticide residues were determined satisfactorily in the tested samples. Thus, this method could be useful for a rapid and simultaneous determination of multi-class pesticide residues in various vegetables and fruits.

The influence of validity criteria on Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test-retest reliability among high school athletes.

PubMed

Brett, Benjamin L; Solomon, Gary S

2017-04-01

Research findings to date on the stability of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Composite scores have been inconsistent, requiring further investigation. The use of test validity criteria across these studies also has been inconsistent. Using multiple measures of stability, we examined test-retest reliability of repeated ImPACT baseline assessments in high school athletes across various validity criteria reported in previous studies. A total of 1146 high school athletes completed baseline cognitive testing using the online ImPACT test battery at two time periods of approximately two-year intervals. No participant sustained a concussion between assessments. Five forms of validity criteria used in previous test-retest studies were applied to the data, and differences in reliability were compared. Intraclass correlation coefficients (ICCs) ranged in composite scores from .47 (95% confidence interval, CI [.38, .54]) to .83 (95% CI [.81, .85]) and showed little change across a two-year interval for all five sets of validity criteria. Regression based methods (RBMs) examining the test-retest stability demonstrated a lack of significant change in composite scores across the two-year interval for all forms of validity criteria, with no cases falling outside the expected range of 90% confidence intervals. The application of more stringent validity criteria does not alter test-retest reliability, nor does it account for some of the variation observed across previously performed studies. As such, use of the ImPACT manual validity criteria should be utilized in the determination of test validity and in the individualized approach to concussion management. Potential future efforts to improve test-retest reliability are discussed.

An alternative to the balance error scoring system: using a low-cost balance board to improve the validity/reliability of sports-related concussion balance testing.

PubMed

Chang, Jasper O; Levy, Susan S; Seay, Seth W; Goble, Daniel J

2014-05-01

Recent guidelines advocate sports medicine professionals to use balance tests to assess sensorimotor status in the management of concussions. The present study sought to determine whether a low-cost balance board could provide a valid, reliable, and objective means of performing this balance testing. Criterion validity testing relative to a gold standard and 7 day test-retest reliability. University biomechanics laboratory. Thirty healthy young adults. Balance ability was assessed on 2 days separated by 1 week using (1) a gold standard measure (ie, scientific grade force plate), (2) a low-cost Nintendo Wii Balance Board (WBB), and (3) the Balance Error Scoring System (BESS). Validity of the WBB center of pressure path length and BESS scores were determined relative to the force plate data. Test-retest reliability was established based on intraclass correlation coefficients. Composite scores for the WBB had excellent validity (r = 0.99) and test-retest reliability (R = 0.88). Both the validity (r = 0.10-0.52) and test-retest reliability (r = 0.61-0.78) were lower for the BESS. These findings demonstrate that a low-cost balance board can provide improved balance testing accuracy/reliability compared with the BESS. This approach provides a potentially more valid/reliable, yet affordable, means of assessing sports-related concussion compared with current methods.

Evaluation of the Thermo Scientific™ SureTect™ Listeria species Assay.

PubMed

Cloke, Jonathan; Evans, Katharine; Crabtree, David; Hughes, Annette; Simpson, Helen; Holopainen, Jani; Wickstrand, Nina; Kauppinen, Mikko

2014-03-01

The Thermo Scientific™ SureTect™ Listeria species Assay is a new real-time PCR assay for the detection of all species of Listeria in food and environmental samples. This validation study was conducted using the AOAC Research Institute (RI) Performance Tested MethodsSM program to validate the SureTect Listeria species Assay in comparison to the reference method detailed in International Organization for Standardization 11290-1:1996 including amendment 1:2004 in a variety of foods plus plastic and stainless steel. The food matrixes validated were smoked salmon, processed cheese, fresh bagged spinach, cantaloupe, cooked prawns, cooked sliced turkey meat, cooked sliced ham, salami, pork frankfurters, and raw ground beef. All matrixes were tested by Thermo Fisher Scientific, Microbiology Division, Basingstoke, UK. In addition, three matrixes (pork frankfurters, fresh bagged spinach, and stainless steel surface samples) were analyzed independently as part of the AOAC-RI-controlled independent laboratory study by the University of Guelph, Canada. Using probability of detection statistical analysis, a significant difference in favour of the SureTect assay was demonstrated between the SureTect and reference method for high level spiked samples of pork frankfurters, smoked salmon, cooked prawns, stainless steel, and low-spiked samples of salami. For all other matrixes, no significant difference was seen between the two methods during the study. Inclusivity testing was conducted with 68 different isolates of Listeria species, all of which were detected by the SureTect Listeria species Assay. None of the 33 exclusivity isolates were detected by the SureTect Listeria species Assay. Ruggedness testing was conducted to evaluate the performance of the assay with specific method deviations outside of the recommended parameters open to variation, which demonstrated that the assay gave reliable performance. Accelerated stability testing was additionally conducted, validating the assay shelf life.

Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed Central

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-01-01

Background: Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. Aims: To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Study Design: Methodological and cross sectional study. Methods: A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. Results: The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. Conclusion: The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain. PMID:29843496

Assessment of human epidermal model LabCyte EPI-MODEL for in vitro skin irritation testing according to European Centre for the Validation of Alternative Methods (ECVAM)-validated protocol.

PubMed

Katoh, Masakazu; Hamajima, Fumiyasu; Ogasawara, Takahiro; Hata, Ken-Ichiro

2009-06-01

A validation study of an in vitro skin irritation testing method using a reconstructed human skin model has been conducted by the European Centre for the Validation of Alternative Methods (ECVAM), and a protocol using EpiSkin (SkinEthic, France) has been approved. The structural and performance criteria of skin models for testing are defined in the ECVAM Performance Standards announced along with the approval. We have performed several evaluations of the new reconstructed human epidermal model LabCyte EPI-MODEL, and confirmed that it is applicable to skin irritation testing as defined in the ECVAM Performance Standards. We selected 19 materials (nine irritants and ten non-irritants) available in Japan as test chemicals among the 20 reference chemicals described in the ECVAM Performance Standard. A test chemical was applied to the surface of the LabCyte EPI-MODEL for 15 min, after which it was completely removed and the model then post-incubated for 42 hr. Cell v iability was measured by MTT assay and skin irritancy of the test chemical evaluated. In addition, interleukin-1 alpha (IL-1alpha) concentration in the culture supernatant after post-incubation was measured to provide a complementary evaluation of skin irritation. Evaluation of the 19 test chemicals resulted in 79% accuracy, 78% sensitivity and 80% specificity, confirming that the in vitro skin irritancy of the LabCyte EPI-MODEL correlates highly with in vivo skin irritation. These results suggest that LabCyte EPI-MODEL is applicable to the skin irritation testing protocol set out in the ECVAM Performance Standards.

Comparison of human skin irritation patch test data with in vitro skin irritation assays and animal data.

PubMed

Jírová, Dagmar; Basketter, David; Liebsch, Manfred; Bendová, Hana; Kejlová, Kristina; Marriott, Marie; Kandárová, Helena

2010-02-01

Efforts to replace the rabbit skin irritation test have been underway for many years, encouraged by the EU Cosmetics Directive and REACH. Recently various in vitro tests have been developed, evaluated and validated. A key difficulty in confirming the validity of in vitro methods is that animal data are scarce and of limited utility for prediction of human effects, which adversely impacts their acceptance. This study examines whether in vivo or in vitro data most accurately predicted human effects. Using the 4-hr human patch test (HPT) we examined a number of chemicals whose EU classification of skin irritancy is known to be borderline, or where in vitro methods provided conflicting results. Of the 16 chemicals classified as irritants in the rabbit, only five substances were found to be significantly irritating to human skin. Concordance of the rabbit test with the 4-hr HPT was only 56%, whereas concordance of human epidermis models with human data was 76% (EpiDerm) and 70% (EPISKIN). The results confirm observations that rabbits overpredict skin effects in humans. Therefore, when validating in vitro methods, all available information, including human data, should be taken into account before making conclusions about their predictive capacity.

Reliability and validity of the closed kinetic chain upper extremity stability test.

PubMed

Lee, Dong-Rour; Kim, Laurentius Jongsoon

2015-04-01

[Purpose] The purpose of this study was to examine the reliability and validity of the Closed Kinetic Chain Upper Extremity Stability (CKCUES) test. [Subjects and Methods] A sample of 40 subjects (20 males, 20 females) with and without pain in the upper limbs was recruited. The subjects were tested twice, three days apart to assess the reliability of the CKCUES test. The CKCUES test was performed four times, and the average was calculated using the data of the last 3 tests. In order to test the validity of the CKCUES test, peak torque of internal/external shoulder rotation was measured using an isokinetic dynamometer, and maximum grip strength was measured using a hand dynamometer, and their Pearson correlation coefficients with the average values of the CKCUES test were calculated. [Results] The reliability of the CKCUES test was very high (ICC=0.97). The correlations between the CKCUES test and maximum grip strength (r=0.78-0.79), and the peak torque of internal/external shoulder rotation (r=0.87-0.94) were high indicating its validity. [Conclusion] The reliability and validity of the CKCUES test were high. The CKCUES test is expected to be used for clinical tests on upper limb stability at low price.

Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods.

PubMed

Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J Sunil

2014-08-01

We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called "Patient Recursive Survival Peeling" is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called "combined" cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication.

Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods

PubMed Central

Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil

2015-01-01

We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called “Patient Recursive Survival Peeling” is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called “combined” cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication. PMID:26997922

Cosmetics Europe multi-laboratory pre-validation of the SkinEthic™ reconstituted human corneal epithelium test method for the prediction of eye irritation.

PubMed

Alépée, N; Bessou-Touya, S; Cotovio, J; de Smedt, A; de Wever, B; Faller, C; Jones, P; Le Varlet, B; Marrec-Fairley, M; Pfannenbecker, U; Tailhardat, M; van Goethem, F; McNamee, P

2013-08-01

Cosmetics Europe, The Personal Care Association, known as Colipa before 2012, conducted a program of technology transfer and assessment of Within/Between Laboratory (WLV/BLV) reproducibility of the SkinEthic™ Reconstituted Human Corneal Epithelium (HCE) as one of two human reconstructed tissue eye irritation test methods. The SkinEthic™ HCE test method involves two exposure time treatment procedures - one for short time exposure (10 min - SE) and the other for long time exposure (60 min - LE) of tissues to test substance. This paper describes pre-validation studies of the SkinEthic™ HCE test method (SE and LE protocols) as well as the Eye Peptide Reactivity Assay (EPRA). In the SE WLV study, 30 substances were evaluated. A consistent outcome with respect to viability measurement across all runs was observed with all substances showing an SD of less than 18%. In the LE WLV study, 44 out of 45 substances were consistently classified. These data demonstrated a high level of reproducibility within laboratory for both the SE and LE treatment procedures. For the LE BLV, 19 out of 20 substances were consistently classified between the three laboratories, again demonstrating a high level of reproducibility between laboratories. The results for EPRA WLV and BLV studies demonstrated that all substances analysed were categorised similarly and that the method is reproducible. The SkinEthic™ HCE test method entered into the experimental phase of a formal ECVAM validation program in 2010. Copyright © 2013. Published by Elsevier Ltd.

High-voltage leak detection of a parenteral proteinaceous solution product packaged in form-fill-seal plastic laminate bags. Part 1. Method development and validation.

PubMed

Damgaard, Rasmus; Rasmussen, Mats; Buus, Peter; Mulhall, Brian; Guazzo, Dana Morton

2013-01-01

In Part 1 of this three-part research series, a leak test performed using high-voltage leak detection (HVLD) technology, also referred to as an electrical conductivity and capacitance leak test, was developed and validated for container-closure integrity verification of a small-volume laminate plastic bag containing an aqueous solution for injection. The sterile parenteral product is the rapid-acting insulin analogue, insulin aspart (NovoRapid®/NovoLog®, by Novo Nordisk A/S, Bagsværd, Denmark). The aseptically filled and sealed package is designed to preserve product sterility through expiry. Method development and validation work incorporated positive control packages with a single hole laser-drilled through the laminate film of each bag. A unique HVLD method characterized by specific high-voltage and potentiometer set points was established for testing bags positioned in each of three possible orientations as they are conveyed through the instrument's test zone in each of two possible directions-resulting in a total of six different test method options. Validation study results successfully demonstrated the ability of all six methods to accurately and reliably detect those packages with laser-drilled holes from 2.5-11.2 μm in nominal diameter. Part 2 of this series will further explore HVLD test results as a function of package seal and product storage variables. The final Part 3 will report the impact of HVLD exposure on product physico-chemical stability. In this Part 1 of a three-part research series, a leak test method based on electrical conductivity and capacitance, called high voltage leak detection (HVLD), was used to find leaks in small plastic bags filled with an insulin pharmaceutical solution for human injection by Novo Nordisk A/S (Bagsværd, Denmark). To perform the test, the package is electrically grounded while being conveyed past an electrode linked to a high-voltage, low-amperage transformer. The instrument measures the current that passes from the transformer to the electrode, through the packaged product and along the package walls, to the ground. Plastic packages without defect are relatively nonconductive and yield a low voltage reading; a leaking package with electrically conductive solution located in or near the leak triggers a spike in voltage reading. Test methods were optimized and validated, enabling the detection of leaking packages with holes as small as 2.5 μm in diameter. Part 2 of this series will further explore HVLD test results as a function of package seal and product storage variables. The final Part 3 will report the impact of HVLD exposure on product stability.

[Inappropriate test methods in allergy].

PubMed

Kleine-Tebbe, J; Herold, D A

2010-11-01

Inappropriate test methods are increasingly utilized to diagnose allergy. They fall into two categories: I. Tests with obscure theoretical basis, missing validity and lacking reproducibility, such as bioresonance, electroacupuncture, applied kinesiology and the ALCAT-test. These methods lack both the technical and clinical validation needed to justify their use. II. Tests with real data, but misleading interpretation: Detection of IgG or IgG4-antibodies or lymphocyte proliferation tests to foods do not allow to separate healthy from diseased subjects, neither in case of food intolerance, allergy or other diagnoses. The absence of diagnostic specificity induces many false positive findings in healthy subjects. As a result unjustified diets might limit quality of life and lead to malnutrition. Proliferation of lymphocytes in response to foods can show elevated rates in patients with allergies. These values do not allow individual diagnosis of hypersensitivity due to their broad variation. Successful internet marketing, infiltration of academic programs and superficial reporting by the media promote the popularity of unqualified diagnostic tests; also in allergy. Therefore, critical observation and quick analysis of and clear comments to unqualified methods by the scientific medical societies are more important than ever.

Implementation of the 3Rs (refinement, reduction, and replacement): validation and regulatory acceptance considerations for alternative toxicological test methods.

PubMed

Schechtman, Leonard M

2002-01-01

Toxicological testing in the current regulatory environment is steeped in a history of using animals to answer questions about the safety of products to which humans are exposed. That history forms the basis for the testing strategies that have evolved to satisfy the needs of the regulatory bodies that render decisions that affect, for the most part, virtually all phases of premarket product development and evaluation and, to a lesser extent, postmarketing surveillance. Only relatively recently have the levels of awareness of, and responsiveness to, animal welfare issues reached current proportions. That paradigm shift, although sluggish, has nevertheless been progressive. New and alternative toxicological methods for hazard evaluation and risk assessment have now been adopted and are being viewed as a means to address those issues in a manner that considers humane treatment of animals yet maintains scientific credibility and preserves the goal of ensuring human safety. To facilitate this transition, regulatory agencies and regulated industry must work together toward improved approaches. They will need assurance that the methods will be reliable and the results comparable with, or better than, those derived from the current classical methods. That confidence will be a function of the scientific validation and resultant acceptance of any given method. In the United States, to fulfill this need, the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) and its operational center, the National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM), have been constituted as prescribed in federal law. Under this mandate, ICCVAM has developed a process and established criteria for the scientific validation and regulatory acceptance of new and alternative methods. The role of ICCVAM in the validation and acceptance process and the criteria instituted toward that end are described. Also discussed are the participation of the US Food and Drug Administration (FDA) in the ICCVAM process and that agency's approach to the application and implementation of ICCVAM-recommended methods.

Testing and Validation of the Dynamic Interia Measurement Method

NASA Technical Reports Server (NTRS)

Chin, Alexander; Herrera, Claudia; Spivey, Natalie; Fladung, William; Cloutier, David

2015-01-01

This presentation describes the DIM method and how it measures the inertia properties of an object by analyzing the frequency response functions measured during a ground vibration test (GVT). The DIM method has been in development at the University of Cincinnati and has shown success on a variety of small scale test articles. The NASA AFRC version was modified for larger applications.

Psychometric Arabic Sino-Nasal Outcome Test-22: validation and translation in chronic rhinosinusitis patients.

PubMed

Alanazy, Fatma; Dousary, Surayie Al; Albosaily, Ahmed; Aldriweesh, Turki; Alsaleh, Saad; Aldrees, Turki

2018-01-01

The Sino-Nasal Outcome Test (SNOT)-22 has multiple items that reflect how nasal disease affects quality of life. Currently, no validated Arabic version of the SNOT-22 is available. . To develop an Arabic-validated version of SNOT-22. Prospective. Tertiary care center. This single-center validation study was conducted between 2015 and 2017 at King Abdul-Aziz University Hospital, Riyadh, Saudi Arabia. The SNOT-22 English version was translated into Arabic by the forward and backward method. The test and retest reliability, internal consistency, responsiveness to surgical treatment, discriminant validity, sensitivity and specificity all were tested. Validated Arabic version of the SNOT-22. Of 265 individuals, 171 were healthy volunteers and 94 were chronic rhinosinusitis patients. The Arabic version showed high internal consistency (Cronbach's of 0.94), and the ability to differentiate between diseased and healthy volunteers (P < .001). The translated versions demonstrated the ability to detect the change scores significantly in response to intervention (P < .001). This is the first validated Arabic version of SNOT-22. The instrument can be used among the Arabic population. No subjects from other Arab countries.

Space Suit Joint Torque Testing

NASA Technical Reports Server (NTRS)

Valish, Dana J.

2011-01-01

In 2009 and early 2010, a test was performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design meets the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future space suits. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis and a variance in torque values for some of the tested joints was apparent. Potential variables that could have affected the data were identified and re-testing was conducted in an attempt to eliminate these variables. The results of the retest will be used to determine if further testing and modification is necessary before the method can be validated.

The selection of air traffic control specialists : two studies demonstrating methods to insure an accurate validity coefficient for selection devices.

DOT National Transportation Integrated Search

1979-03-01

There are several conditions that can influence the calculation of the statistical validity of a test battery such as that used to selected Air Traffic Control Specialists. Two conditions of prime importance to statistical validity are recruitment pr...

Evaluation of Validity and Reliability for Hierarchical Scales Using Latent Variable Modeling

ERIC Educational Resources Information Center

Raykov, Tenko; Marcoulides, George A.

2012-01-01

A latent variable modeling method is outlined, which accomplishes estimation of criterion validity and reliability for a multicomponent measuring instrument with hierarchical structure. The approach provides point and interval estimates for the scale criterion validity and reliability coefficients, and can also be used for testing composite or…

Cognitive Testing with Female Nutrition and Education Assistance Program Participants Informs Validity of the Satter Eating Competence Inventory

ERIC Educational Resources Information Center

Krall, Jodi Stotts; Lohse, Barbara

2010-01-01

Objective: Examine the validity of a self-report measure of eating competence with low-income women. Methods: Twenty-five females (18-49 years old) recruited from low-income venues in Pennsylvania completed cognitive testing through an iterative interview process. Respondents' oral responses were compared to researchers' intended meaning of…

Testing the Construct Validity of Proposed Criteria for "DSM-5" Autism Spectrum Disorder

ERIC Educational Resources Information Center

Mandy, William P. L.; Charman, Tony; Skuse, David H.

2012-01-01

Objective: To use confirmatory factor analysis to test the construct validity of the proposed "DSM-5" symptom model of autism spectrum disorder (ASD), in comparison to alternative models, including that described in "DSM-IV-TR." Method: Participants were 708 verbal children and young persons (mean age, 9.5 years) with mild to severe autistic…

Validity and Bias of Academic Achievement Measures in the First Year of Elementary School

ERIC Educational Resources Information Center

Hammes, Patricia Simone; Bigras, Marc; Crepaldi, Maria Aparecida

2016-01-01

We tested the criterion-related validity and potential bias of two measures of pupils' academic achievement: the Teacher Rating Scale (TRS) and the Mathematics and Literacy Achievement Tests (MLTs). These measures are representative of assessment methods largely used in the elementary school. The aims were: (1) to verify the extent to which TRS…

The Impact of Model Parameterization and Estimation Methods on Tests of Measurement Invariance with Ordered Polytomous Data

ERIC Educational Resources Information Center

Koziol, Natalie A.; Bovaird, James A.

2018-01-01

Evaluations of measurement invariance provide essential construct validity evidence--a prerequisite for seeking meaning in psychological and educational research and ensuring fair testing procedures in high-stakes settings. However, the quality of such evidence is partly dependent on the validity of the resulting statistical conclusions. Type I or…

Validity of Willingness to Pay Measures under Preference Uncertainty.

PubMed

Braun, Carola; Rehdanz, Katrin; Schmidt, Ulrich

2016-01-01

Recent studies in the marketing literature developed a new method for eliciting willingness to pay (WTP) with an open-ended elicitation format: the Range-WTP method. In contrast to the traditional approach of eliciting WTP as a single value (Point-WTP), Range-WTP explicitly allows for preference uncertainty in responses. The aim of this paper is to apply Range-WTP to the domain of contingent valuation and to test for its theoretical validity and robustness in comparison to the Point-WTP. Using data from two novel large-scale surveys on the perception of solar radiation management (SRM), a little-known technique for counteracting climate change, we compare the performance of both methods in the field. In addition to the theoretical validity (i.e. the degree to which WTP values are consistent with theoretical expectations), we analyse the test-retest reliability and stability of our results over time. Our evidence suggests that the Range-WTP method clearly outperforms the Point-WTP method.

Validity of Willingness to Pay Measures under Preference Uncertainty

PubMed Central

Braun, Carola; Rehdanz, Katrin; Schmidt, Ulrich

2016-01-01

Recent studies in the marketing literature developed a new method for eliciting willingness to pay (WTP) with an open-ended elicitation format: the Range-WTP method. In contrast to the traditional approach of eliciting WTP as a single value (Point-WTP), Range-WTP explicitly allows for preference uncertainty in responses. The aim of this paper is to apply Range-WTP to the domain of contingent valuation and to test for its theoretical validity and robustness in comparison to the Point-WTP. Using data from two novel large-scale surveys on the perception of solar radiation management (SRM), a little-known technique for counteracting climate change, we compare the performance of both methods in the field. In addition to the theoretical validity (i.e. the degree to which WTP values are consistent with theoretical expectations), we analyse the test-retest reliability and stability of our results over time. Our evidence suggests that the Range-WTP method clearly outperforms the Point-WTP method. PMID:27096163

Evaluation of PDA Technical Report No 33. Statistical Testing Recommendations for a Rapid Microbiological Method Case Study.

PubMed

Murphy, Thomas; Schwedock, Julie; Nguyen, Kham; Mills, Anna; Jones, David

2015-01-01

New recommendations for the validation of rapid microbiological methods have been included in the revised Technical Report 33 release from the PDA. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This case study applies those statistical methods to accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological methods system being evaluated for water bioburden testing. Results presented demonstrate that the statistical methods described in the PDA Technical Report 33 chapter can all be successfully applied to the rapid microbiological method data sets and gave the same interpretation for equivalence to the standard method. The rapid microbiological method was in general able to pass the requirements of PDA Technical Report 33, though the study shows that there can be occasional outlying results and that caution should be used when applying statistical methods to low average colony-forming unit values. Prior to use in a quality-controlled environment, any new method or technology has to be shown to work as designed by the manufacturer for the purpose required. For new rapid microbiological methods that detect and enumerate contaminating microorganisms, additional recommendations have been provided in the revised PDA Technical Report No. 33. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This paper applies those statistical methods to analyze accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological method system being validated for water bioburden testing. The case study demonstrates that the statistical methods described in the PDA Technical Report No. 33 chapter can be successfully applied to rapid microbiological method data sets and give the same comparability results for similarity or difference as the standard method. © PDA, Inc. 2015.

Parent- and Self-Reported Dimensions of Oppositionality in Youth: Construct Validity, Concurrent Validity, and the Prediction of Criminal Outcomes in Adulthood

ERIC Educational Resources Information Center

Aebi, Marcel; Plattner, Belinda; Metzke, Christa Winkler; Bessler, Cornelia; Steinhausen, Hans-Christoph

2013-01-01

Background: Different dimensions of oppositional defiant disorder (ODD) have been found as valid predictors of further mental health problems and antisocial behaviors in youth. The present study aimed at testing the construct, concurrent, and predictive validity of ODD dimensions derived from parent- and self-report measures. Method: Confirmatory…

An Efficient Data Partitioning to Improve Classification Performance While Keeping Parameters Interpretable.

PubMed

Korjus, Kristjan; Hebart, Martin N; Vicente, Raul

2016-01-01

Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier's generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term "Cross-validation and cross-testing" improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do.

Validation of quantitative and qualitative methods for detecting allergenic ingredients in processed foods in Japan.

PubMed

Sakai, Shinobu; Adachi, Reiko; Akiyama, Hiroshi; Teshima, Reiko

2013-06-19

A labeling system for food allergenic ingredients was established in Japan in April 2002. To monitor the labeling, the Japanese government announced official methods for detecting allergens in processed foods in November 2002. The official methods consist of quantitative screening tests using enzyme-linked immunosorbent assays (ELISAs) and qualitative confirmation tests using Western blotting or polymerase chain reactions (PCR). In addition, the Japanese government designated 10 μg protein/g food (the corresponding allergenic ingredient soluble protein weight/food weight), determined by ELISA, as the labeling threshold. To standardize the official methods, the criteria for the validation protocol were described in the official guidelines. This paper, which was presented at the Advances in Food Allergen Detection Symposium, ACS National Meeting and Expo, San Diego, CA, Spring 2012, describes the validation protocol outlined in the official Japanese guidelines, the results of interlaboratory studies for the quantitative detection method (ELISA for crustacean proteins) and the qualitative detection method (PCR for shrimp and crab DNAs), and the reliability of the detection methods.

Validation of a two-dimensional liquid chromatography method for quality control testing of pharmaceutical materials.

PubMed

Yang, Samuel H; Wang, Jenny; Zhang, Kelly

2017-04-07

Despite the advantages of 2D-LC, there is currently little to no work in demonstrating the suitability of these 2D-LC methods for use in a quality control (QC) environment for good manufacturing practice (GMP) tests. This lack of information becomes more critical as the availability of commercial 2D-LC instrumentation has significantly increased, and more testing facilities begin to acquire these 2D-LC capabilities. It is increasingly important that the transferability of developed 2D-LC methods be assessed in terms of reproducibility, robustness and performance across different laboratories worldwide. The work presented here focuses on the evaluation of a heart-cutting 2D-LC method used for the analysis of a pharmaceutical material, where a key, co-eluting impurity in the first dimension ( 1 D) is resolved from the main peak and analyzed in the second dimension ( 2 D). A design-of-experiments (DOE) approach was taken in the collection of the data, and the results were then modeled in order to evaluate method robustness using statistical modeling software. This quality by design (QBD) approach gives a deeper understanding of the impact of these 2D-LC critical method attributes (CMAs) and how they affect overall method performance. Although there are multiple parameters that may be critical from method development point of view, a special focus of this work is devoted towards evaluation of unique 2D-LC critical method attributes from method validation perspective that transcend conventional method development and validation. The 2D-LC method attributes are evaluated for their recovery, peak shape, and resolution of the two co-eluting compounds in question on the 2 D. In the method, linearity, accuracy, precision, repeatability, and sensitivity are assessed along with day-to-day, analyst-to-analyst, and lab-to-lab (instrument-to-instrument) assessments. The results of this validation study demonstrate that the 2D-LC method is accurate, sensitive, and robust and is ultimately suitable for QC testing with good method transferability. Copyright © 2017 Elsevier B.V. All rights reserved.

Validation of Blockage Interference Corrections in the National Transonic Facility

NASA Technical Reports Server (NTRS)

Walker, Eric L.

2007-01-01

A validation test has recently been constructed for wall interference methods as applied to the National Transonic Facility (NTF). The goal of this study was to begin to address the uncertainty of wall-induced-blockage interference corrections, which will make it possible to address the overall quality of data generated by the facility. The validation test itself is not specific to any particular modeling. For this present effort, the Transonic Wall Interference Correction System (TWICS) as implemented at the NTF is the mathematical model being tested. TWICS uses linear, potential boundary conditions that must first be calibrated. These boundary conditions include three different classical, linear. homogeneous forms that have been historically used to approximate the physical behavior of longitudinally slotted test section walls. Results of the application of the calibrated wall boundary conditions are discussed in the context of the validation test.

Validity and extension of the SCS-CN method for computing infiltration and rainfall-excess rates

NASA Astrophysics Data System (ADS)

Mishra, Surendra Kumar; Singh, Vijay P.

2004-12-01

A criterion is developed for determining the validity of the Soil Conservation Service curve number (SCS-CN) method. According to this criterion, the existing SCS-CN method is found to be applicable when the potential maximum retention, S, is less than or equal to twice the total rainfall amount. The criterion is tested using published data of two watersheds. Separating the steady infiltration from capillary infiltration, the method is extended for predicting infiltration and rainfall-excess rates. The extended SCS-CN method is tested using 55 sets of laboratory infiltration data on soils varying from Plainfield sand to Yolo light clay, and the computed and observed infiltration and rainfall-excess rates are found to be in good agreement.

Improving machine learning reproducibility in genetic association studies with proportional instance cross validation (PICV).

PubMed

Piette, Elizabeth R; Moore, Jason H

2018-01-01

Machine learning methods and conventions are increasingly employed for the analysis of large, complex biomedical data sets, including genome-wide association studies (GWAS). Reproducibility of machine learning analyses of GWAS can be hampered by biological and statistical factors, particularly so for the investigation of non-additive genetic interactions. Application of traditional cross validation to a GWAS data set may result in poor consistency between the training and testing data set splits due to an imbalance of the interaction genotypes relative to the data as a whole. We propose a new cross validation method, proportional instance cross validation (PICV), that preserves the original distribution of an independent variable when splitting the data set into training and testing partitions. We apply PICV to simulated GWAS data with epistatic interactions of varying minor allele frequencies and prevalences and compare performance to that of a traditional cross validation procedure in which individuals are randomly allocated to training and testing partitions. Sensitivity and positive predictive value are significantly improved across all tested scenarios for PICV compared to traditional cross validation. We also apply PICV to GWAS data from a study of primary open-angle glaucoma to investigate a previously-reported interaction, which fails to significantly replicate; PICV however improves the consistency of testing and training results. Application of traditional machine learning procedures to biomedical data may require modifications to better suit intrinsic characteristics of the data, such as the potential for highly imbalanced genotype distributions in the case of epistasis detection. The reproducibility of genetic interaction findings can be improved by considering this variable imbalance in cross validation implementation, such as with PICV. This approach may be extended to problems in other domains in which imbalanced variable distributions are a concern.

Improving validation methods for molecular diagnostics: application of Bland-Altman, Deming and simple linear regression analyses in assay comparison and evaluation for next-generation sequencing

PubMed Central

Misyura, Maksym; Sukhai, Mahadeo A; Kulasignam, Vathany; Zhang, Tong; Kamel-Reid, Suzanne; Stockley, Tracy L

2018-01-01

Aims A standard approach in test evaluation is to compare results of the assay in validation to results from previously validated methods. For quantitative molecular diagnostic assays, comparison of test values is often performed using simple linear regression and the coefficient of determination (R2), using R2 as the primary metric of assay agreement. However, the use of R2 alone does not adequately quantify constant or proportional errors required for optimal test evaluation. More extensive statistical approaches, such as Bland-Altman and expanded interpretation of linear regression methods, can be used to more thoroughly compare data from quantitative molecular assays. Methods We present the application of Bland-Altman and linear regression statistical methods to evaluate quantitative outputs from next-generation sequencing assays (NGS). NGS-derived data sets from assay validation experiments were used to demonstrate the utility of the statistical methods. Results Both Bland-Altman and linear regression were able to detect the presence and magnitude of constant and proportional error in quantitative values of NGS data. Deming linear regression was used in the context of assay comparison studies, while simple linear regression was used to analyse serial dilution data. Bland-Altman statistical approach was also adapted to quantify assay accuracy, including constant and proportional errors, and precision where theoretical and empirical values were known. Conclusions The complementary application of the statistical methods described in this manuscript enables more extensive evaluation of performance characteristics of quantitative molecular assays, prior to implementation in the clinical molecular laboratory. PMID:28747393

Methodology for Developing a New EFNEP Food and Physical Activity Behaviors Questionnaire.

PubMed

Murray, Erin K; Auld, Garry; Baker, Susan S; Barale, Karen; Franck, Karen; Khan, Tarana; Palmer-Keenan, Debra; Walsh, Jennifer

2017-10-01

Research methods are described for developing a food and physical activity behaviors questionnaire for the Expanded Food and Nutrition Education Program (EFNEP), a US Department of Agriculture nutrition education program serving low-income families. Mixed-methods observational study. The questionnaire will include 5 domains: (1) diet quality, (2) physical activity, (3) food safety, (4) food security, and (5) food resource management. A 5-stage process will be used to assess the questionnaire's test-retest reliability and content, face, and construct validity. Research teams across the US will coordinate questionnaire development and testing nationally. Convenience samples of low-income EFNEP, or EFNEP-eligible, adult participants across the US. A 5-stage process: (1) prioritize domain concepts to evaluate (2) question generation and content analysis panel, (3) question pretesting using cognitive interviews, (4) test-retest reliability assessment, and (5) construct validity testing. A nationally tested valid and reliable food and physical activity behaviors questionnaire for low-income adults to evaluate EFNEP's effectiveness. Cognitive interviews will be summarized to identify themes and dominant trends. Paired t tests (P ≤ .05) and Spearman and intra-class correlation coefficients (r > .5) will be conducted to assess reliability. Construct validity will be assessed using Wilcoxon t test (P ≤ .05), Spearman correlations, and Bland-Altman plots. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Sub-categorisation of skin corrosive chemicals by the EpiSkin™ reconstructed human epidermis skin corrosion test method according to UN GHS: revision of OECD Test Guideline 431.

PubMed

Alépée, N; Grandidier, M H; Cotovio, J

2014-03-01

The EpiSkin™ skin corrosion test method was formally validated and adopted within the context of OECD TG 431 for identifying corrosive and non-corrosive chemicals. The EU Classification, Labelling and Packaging Regulation (EU CLP) system requires the sub-categorisation of corrosive chemicals into the three UN GHS optional subcategories 1A, 1B and 1C. The present study was undertaken to investigate the usefulness of the validated EpiSkin™ test method to identify skin corrosive UN GHS Categories 1A, 1B and 1C using the original and validated prediction model and adapted controls for direct MTT reduction. In total, 85 chemicals selected by the OECD expert group on skin corrosion were tested in three independent runs. The results obtained were highly reproducible both within (>80%) and between (>78%) laboratories when compared with historical data. Moreover the results obtained showed that the EpiSkin™ test method is highly sensitive (99%) and specific (80%) in discriminating corrosive from non-corrosive chemicals and allows reliable and relevant identification of the different skin corrosive UN GHS subcategories, with high accuracies being obtained for both UN GHS Categories 1A (83%) and 1B/1C (76%) chemicals. The overall accuracy of the test method to subcategorise corrosive chemicals into three or two UN GHS subcategories ranged from 75% to 79%. Considering those results, the revised OECD Test Guideline 431 permit the use of EpiSkin™ for subcategorising corrosive chemicals into at least two classes (Category 1A and Category 1B/1C). Copyright © 2013. Published by Elsevier Ltd.

Translation, cultural adaptation and validation of the Diabetes Attitudes Scale - third version into Brazilian Portuguese 1

PubMed Central

Vieira, Gisele de Lacerda Chaves; Pagano, Adriana Silvino; Reis, Ilka Afonso; Rodrigues, Júlia Santos Nunes; Torres, Heloísa de Carvalho

2018-01-01

ABSTRACT Objective: to perform the translation, adaptation and validation of the Diabetes Attitudes Scale - third version instrument into Brazilian Portuguese. Methods: methodological study carried out in six stages: initial translation, synthesis of the initial translation, back-translation, evaluation of the translated version by the Committee of Judges (27 Linguists and 29 health professionals), pre-test and validation. The pre-test and validation (test-retest) steps included 22 and 120 health professionals, respectively. The Content Validity Index, the analyses of internal consistency and reproducibility were performed using the R statistical program. Results: in the content validation, the instrument presented good acceptance among the Judges with a mean Content Validity Index of 0.94. The scale presented acceptable internal consistency (Cronbach’s alpha = 0.60), while the correlation of the total score at the test and retest moments was considered high (Polychoric Correlation Coefficient = 0.86). The Intra-class Correlation Coefficient, for the total score, presented a value of 0.65. Conclusion: the Brazilian version of the instrument (Escala de Atitudes dos Profissionais em relação ao Diabetes Mellitus) was considered valid and reliable for application by health professionals in Brazil. PMID:29319739

Validation of science virtual test to assess 8th grade students' critical thinking on living things and environmental sustainability theme

NASA Astrophysics Data System (ADS)

Rusyati, Lilit; Firman, Harry

2017-05-01

This research was motivated by the importance of multiple-choice questions that indicate the elements and sub-elements of critical thinking and implementation of computer-based test. The method used in this research was descriptive research for profiling the validation of science virtual test to measure students' critical thinking in junior high school. The participant is junior high school students of 8th grade (14 years old) while science teacher and expert as the validators. The instrument that used as a tool to capture the necessary data are sheet of an expert judgment, sheet of legibility test, and science virtual test package in multiple choice form with four possible answers. There are four steps to validate science virtual test to measure students' critical thinking on the theme of "Living Things and Environmental Sustainability" in 7th grade Junior High School. These steps are analysis of core competence and basic competence based on curriculum 2013, expert judgment, legibility test and trial test (limited and large trial test). The test item criterion based on trial test are accepted, accepted but need revision, and rejected. The reliability of the test is α = 0.747 that categorized as `high'. It means the test instruments used is reliable and high consistency. The validity of Rxy = 0.63 means that the validity of the instrument was categorized as `high' according to interpretation value of Rxy (correlation).

JaCVAM-organized international validation study of the in vivo rodent alkaline comet assay for detection of genotoxic carcinogens: II. Summary of definitive validation study results.

PubMed

Uno, Yoshifumi; Kojima, Hajime; Omori, Takashi; Corvi, Raffaella; Honma, Masamistu; Schechtman, Leonard M; Tice, Raymond R; Beevers, Carol; De Boeck, Marlies; Burlinson, Brian; Hobbs, Cheryl A; Kitamoto, Sachiko; Kraynak, Andrew R; McNamee, James; Nakagawa, Yuzuki; Pant, Kamala; Plappert-Helbig, Ulla; Priestley, Catherine; Takasawa, Hironao; Wada, Kunio; Wirnitzer, Uta; Asano, Norihide; Escobar, Patricia A; Lovell, David; Morita, Takeshi; Nakajima, Madoka; Ohno, Yasuo; Hayashi, Makoto

2015-07-01

The in vivo rodent alkaline comet assay (comet assay) is used internationally to investigate the in vivo genotoxic potential of test chemicals. This assay, however, has not previously been formally validated. The Japanese Center for the Validation of Alternative Methods (JaCVAM), with the cooperation of the U.S. NTP Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM)/the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), the European Centre for the Validation of Alternative Methods (ECVAM), and the Japanese Environmental Mutagen Society/Mammalian Mutagenesis Study Group (JEMS/MMS), organized an international validation study to evaluate the reliability and relevance of the assay for identifying genotoxic carcinogens, using liver and stomach as target organs. The ultimate goal of this exercise was to establish an Organisation for Economic Co-operation and Development (OECD) test guideline. The study protocol was optimized in the pre-validation studies, and then the definitive (4th phase) validation study was conducted in two steps. In the 1st step, assay reproducibility was confirmed among laboratories using four coded reference chemicals and the positive control ethyl methanesulfonate. In the 2nd step, the predictive capability was investigated using 40 coded chemicals with known genotoxic and carcinogenic activity (i.e., genotoxic carcinogens, genotoxic non-carcinogens, non-genotoxic carcinogens, and non-genotoxic non-carcinogens). Based on the results obtained, the in vivo comet assay is concluded to be highly capable of identifying genotoxic chemicals and therefore can serve as a reliable predictor of rodent carcinogenicity. Copyright © 2015 Elsevier B.V. All rights reserved.

Analysis of QA procedures at the Oregon Department of Transportation.

DOT National Transportation Integrated Search

2010-06-01

This research explored the Oregon Department of Transportation (ODOT) practice of Independent Assurance (IA), : for validation of the contractors test methods, and Verification, for validation of the contractors Quality Control : (QC) data. The...

Psychometrics of the Home Safety Self-Assessment Tool (HSSAT) to prevent falls in community-dwelling older adults.

PubMed

Tomita, Machiko R; Saharan, Sumandeep; Rajendran, Sheela; Nochajski, Susan M; Schweitzer, Jo A

2014-01-01

OBJECTIVE. To identify psychometric properties of the Home Safety Self-Assessment Tool (HSSAT) to prevent falls in community-dwelling older adults. METHOD. We tested content validity, test-retest reliability, interrater reliability, construct validity, convergent and discriminant validity, and responsiveness to change. RESULTS. The content validity index was .98, the intraclass correlation coefficient for test-retest reliability was .97, and the interrater reliability was .89. The difference on identified risk factors between the use and nonuse of the HSSAT was significant (p = .005). Convergent validity with the Centers for Disease Control and Prevention Home Safety Checklist was high (r = .65), and discriminant validity with fear of falling was very low (r = .10). The responsiveness to change was moderate (standardized response mean = 0.57). CONCLUSION. The HSSAT is a reliable and valid instrument to identify fall risks in a home environment, and the HSSAT booklet is effective as educational material leading to improvement in home safety. Copyright © 2014 by the American Occupational Therapy Association, Inc.

Semiquantitative determination of mesophilic, aerobic microorganisms in cocoa products using the Soleris NF-TVC method.

PubMed

Montei, Carolyn; McDougal, Susan; Mozola, Mark; Rice, Jennifer

2014-01-01

The Soleris Non-fermenting Total Viable Count method was previously validated for a wide variety of food products, including cocoa powder. A matrix extension study was conducted to validate the method for use with cocoa butter and cocoa liquor. Test samples included naturally contaminated cocoa liquor and cocoa butter inoculated with natural microbial flora derived from cocoa liquor. A probability of detection statistical model was used to compare Soleris results at multiple test thresholds (dilutions) with aerobic plate counts determined using the AOAC Official Method 966.23 dilution plating method. Results of the two methods were not statistically different at any dilution level in any of the three trials conducted. The Soleris method offers the advantage of results within 24 h, compared to the 48 h required by standard dilution plating methods.

On the analysis of very small samples of Gaussian repeated measurements: an alternative approach.

PubMed

Westgate, Philip M; Burchett, Woodrow W

2017-03-15

The analysis of very small samples of Gaussian repeated measurements can be challenging. First, due to a very small number of independent subjects contributing outcomes over time, statistical power can be quite small. Second, nuisance covariance parameters must be appropriately accounted for in the analysis in order to maintain the nominal test size. However, available statistical strategies that ensure valid statistical inference may lack power, whereas more powerful methods may have the potential for inflated test sizes. Therefore, we explore an alternative approach to the analysis of very small samples of Gaussian repeated measurements, with the goal of maintaining valid inference while also improving statistical power relative to other valid methods. This approach uses generalized estimating equations with a bias-corrected empirical covariance matrix that accounts for all small-sample aspects of nuisance correlation parameter estimation in order to maintain valid inference. Furthermore, the approach utilizes correlation selection strategies with the goal of choosing the working structure that will result in the greatest power. In our study, we show that when accurate modeling of the nuisance correlation structure impacts the efficiency of regression parameter estimation, this method can improve power relative to existing methods that yield valid inference. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Ruggedness testing and validation of a practical analytical method for > 100 veterinary drug residues in bovine muscle by ultrahigh performance liquid chromatography – tandem mass spectrometry

USDA-ARS?s Scientific Manuscript database

In this study, optimization, extension, and validation of a streamlined, qualitative and quantitative multiclass, multiresidue method was conducted to monitor great than100 veterinary drug residues in meat using ultrahigh-performance liquid chromatography – tandem mass spectrometry (UHPLC-MS/MS). I...

Low-cost extrapolation method for maximal LTE radio base station exposure estimation: test and validation.

PubMed

Verloock, Leen; Joseph, Wout; Gati, Azeddine; Varsier, Nadège; Flach, Björn; Wiart, Joe; Martens, Luc

2013-06-01

An experimental validation of a low-cost method for extrapolation and estimation of the maximal electromagnetic-field exposure from long-term evolution (LTE) radio base station installations are presented. No knowledge on downlink band occupation or service characteristics is required for the low-cost method. The method is applicable in situ. It only requires a basic spectrum analyser with appropriate field probes without the need of expensive dedicated LTE decoders. The method is validated both in laboratory and in situ, for a single-input single-output antenna LTE system and a 2×2 multiple-input multiple-output system, with low deviations in comparison with signals measured using dedicated LTE decoders.

Hyper-X: Flight Validation of Hypersonic Airbreathing Technology

NASA Technical Reports Server (NTRS)

Rausch, Vincent L.; McClinton, Charles R.; Crawford, J. Larry

1997-01-01

This paper provides an overview of NASA's focused hypersonic technology program, i.e. the Hyper-X program. This program is designed to move hypersonic, air breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. This paper presents some history leading to the flight test program, research objectives, approach, schedule and status. Substantial experimental data base and concept validation have been completed. The program is concentrating on Mach 7 vehicle development, verification and validation in preparation for wind tunnel testing in 1998 and flight testing in 1999. It is also concentrating on finalization of the Mach 5 and 10 vehicle designs. Detailed evaluation of the Mach 7 vehicle at the flight conditions is nearing completion, and will provide a data base for validation of design methods once flight test data are available.

Integration of design and inspection

NASA Astrophysics Data System (ADS)

Simmonds, William H.

1990-08-01

Developments in advanced computer integrated manufacturing technology, coupled with the emphasis on Total Quality Management, are exposing needs for new techniques to integrate all functions from design through to support of the delivered product. One critical functional area that must be integrated into design is that embracing the measurement, inspection and test activities necessary for validation of the delivered product. This area is being tackled by a collaborative project supported by the UK Government Department of Trade and Industry. The project is aimed at developing techniques for analysing validation needs and for planning validation methods. Within the project an experimental Computer Aided Validation Expert system (CAVE) is being constructed. This operates with a generalised model of the validation process and helps with all design stages: specification of product requirements; analysis of the assurance provided by a proposed design and method of manufacture; development of the inspection and test strategy; and analysis of feedback data. The kernel of the system is a knowledge base containing knowledge of the manufacturing process capabilities and of the available inspection and test facilities. The CAVE system is being integrated into a real life advanced computer integrated manufacturing facility for demonstration and evaluation.

Benchmark tests for a Formula SAE Student car prototyping

NASA Astrophysics Data System (ADS)

Mariasiu, Florin

2011-12-01

Aerodynamic characteristics of a vehicle are important elements in its design and construction. A low drag coefficient brings significant fuel savings and increased engine power efficiency. In designing and developing vehicles trough computer simulation process to determine the vehicles aerodynamic characteristics are using dedicated CFD (Computer Fluid Dynamics) software packages. However, the results obtained by this faster and cheaper method, are validated by experiments in wind tunnels tests, which are expensive and were complex testing equipment are used in relatively high costs. Therefore, the emergence and development of new low-cost testing methods to validate CFD simulation results would bring great economic benefits for auto vehicles prototyping process. This paper presents the initial development process of a Formula SAE Student race-car prototype using CFD simulation and also present a measurement system based on low-cost sensors through which CFD simulation results were experimentally validated. CFD software package used for simulation was Solid Works with the FloXpress add-on and experimental measurement system was built using four piezoresistive force sensors FlexiForce type.

Fatty acid ethyl esters (FAEEs) as markers for alcohol in meconium: method validation and implementation of a screening program for prenatal drug exposure.

PubMed

Hastedt, Martin; Krumbiegel, Franziska; Gapert, René; Tsokos, Michael; Hartwig, Sven

2013-09-01

Alcohol consumption during pregnancy is a widespread problem and can cause severe fetal damage. As the diagnosis of fetal alcohol syndrome is difficult, the implementation of a reliable marker for alcohol consumption during pregnancy into meconium drug screening programs would be invaluable. A previously published gas chromatography mass spectrometry method for the detection of fatty acid ethyl esters (FAEEs) as alcohol markers in meconium was optimized and newly validated for a sample size of 50 mg. This method was applied to 122 cases from a drug-using population. The meconium samples were also tested for common drugs of abuse. In 73 % of the cases, one or more drugs were found. Twenty percent of the samples tested positive for FAEEs at levels indicating significant alcohol exposure. Consequently, alcohol was found to be the third most frequently abused substance within the study group. This re-validated method provides an increase in testing sensitivity, is reliable and easily applicable as part of a drug screening program. It can be used as a non-invasive tool to detect high alcohol consumption in the last trimester of pregnancy. The introduction of FAEEs testing in meconium screening was found to be of particular use in a drug-using population.

Space Suit Joint Torque Measurement Method Validation

NASA Technical Reports Server (NTRS)

Valish, Dana; Eversley, Karina

2012-01-01

In 2009 and early 2010, a test method was developed and performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits. This was done in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design met the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future development programs. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis; the results indicated a significant variance in values reported for a subset of the re-tested joints. Potential variables that could have affected the data were identified and a third round of testing was conducted in an attempt to eliminate and/or quantify the effects of these variables. The results of the third test effort will be used to determine whether or not the proposed joint torque methodology can be applied to future space suit development contracts.

FUNCTIONAL PERFORMANCE TESTING OF THE HIP IN ATHLETES: A SYSTEMATIC REVIEW FOR RELIABILITY AND VALIDITY

PubMed Central

Martin, RobRoy L.

2012-01-01

Purpose/Background: The purpose of this study was to systematically review the literature for functional performance tests with evidence of reliability and validity that could be used for a young, athletic population with hip dysfunction. Methods: A search of PubMed and SPORTDiscus databases were performed to identify movement, balance, hop/jump, or agility functional performance tests from the current peer-reviewed literature used to assess function of the hip in young, athletic subjects. Results: The single-leg stance, deep squat, single-leg squat, and star excursion balance tests (SEBT) demonstrated evidence of validity and normative data for score interpretation. The single-leg stance test and SEBT have evidence of validity with association to hip abductor function. The deep squat test demonstrated evidence as a functional performance test for evaluating femoroacetabular impingement. Hop/Jump tests and agility tests have no reported evidence of reliability or validity in a population of subjects with hip pathology. Conclusions: Use of functional performance tests in the assessment of hip dysfunction has not been well established in the current literature. Diminished squat depth and provocation of pain during the single-leg balance test have been associated with patients diagnosed with FAI and gluteal tendinopathy, respectively. The SEBT and single-leg squat tests provided evidence of convergent validity through an analysis of kinematics and muscle function in normal subjects. Reliability of functional performance tests have not been established on patients with hip dysfunction. Further study is needed to establish reliability and validity of functional performance tests that can be used in a young, athletic population with hip dysfunction. Level of Evidence: 2b (Systematic Review of Literature) PMID:22893860

Spectral signature verification using statistical analysis and text mining

NASA Astrophysics Data System (ADS)

DeCoster, Mallory E.; Firpi, Alexe H.; Jacobs, Samantha K.; Cone, Shelli R.; Tzeng, Nigel H.; Rodriguez, Benjamin M.

2016-05-01

In the spectral science community, numerous spectral signatures are stored in databases representative of many sample materials collected from a variety of spectrometers and spectroscopists. Due to the variety and variability of the spectra that comprise many spectral databases, it is necessary to establish a metric for validating the quality of spectral signatures. This has been an area of great discussion and debate in the spectral science community. This paper discusses a method that independently validates two different aspects of a spectral signature to arrive at a final qualitative assessment; the textual meta-data and numerical spectral data. Results associated with the spectral data stored in the Signature Database1 (SigDB) are proposed. The numerical data comprising a sample material's spectrum is validated based on statistical properties derived from an ideal population set. The quality of the test spectrum is ranked based on a spectral angle mapper (SAM) comparison to the mean spectrum derived from the population set. Additionally, the contextual data of a test spectrum is qualitatively analyzed using lexical analysis text mining. This technique analyzes to understand the syntax of the meta-data to provide local learning patterns and trends within the spectral data, indicative of the test spectrum's quality. Text mining applications have successfully been implemented for security2 (text encryption/decryption), biomedical3 , and marketing4 applications. The text mining lexical analysis algorithm is trained on the meta-data patterns of a subset of high and low quality spectra, in order to have a model to apply to the entire SigDB data set. The statistical and textual methods combine to assess the quality of a test spectrum existing in a database without the need of an expert user. This method has been compared to other validation methods accepted by the spectral science community, and has provided promising results when a baseline spectral signature is present for comparison. The spectral validation method proposed is described from a practical application and analytical perspective.

Validation of a Russian Language Oswestry Disability Index Questionnaire.

PubMed

Yu, Elizabeth M; Nosova, Emily V; Falkenstein, Yuri; Prasad, Priya; Leasure, Jeremi M; Kondrashov, Dimitriy G

2016-11-01

Study Design  Retrospective reliability and validity study. Objective  To validate a recently translated Russian language version of the Oswestry Disability Index (R-ODI) using standardized methods detailed from previous validations in other languages. Methods  We included all subjects who were seen in our spine surgery clinic, over the age of 18, and fluent in the Russian language. R-ODI was translated by six bilingual people and combined into a consensus version. R-ODI and visual analog scale (VAS) questionnaires for leg and back pain were distributed to subjects during both their initial and follow-up visits. Test validity, stability, and internal consistency were measured using standardized psychometric methods. Results Ninety-seven subjects participated in the study. No change in the meaning of the questions on R-ODI was noted with translation from English to Russian. There was a significant positive correlation between R-ODI and VAS scores for both the leg and back during both the initial and follow-up visits ( p  < 0.01 for all). The instrument was shown to have high internal consistency (Cronbach α = 0.82) and moderate test-retest stability (interclass correlation coefficient = 0.70). Conclusions  The R-ODI is both valid and reliable for use among the Russian-speaking population in the United States.

Predicting Job Performance for the Visually Impaired: Validity of the Fine Finger Dexterity Work Task.

ERIC Educational Resources Information Center

Giesen, J. Martin; And Others

The study was designed to determine the reliability and criterion validity of a psychomotor performance test (the Fine Finger Dexterity Work Task Unit) with 40 partially or totally blind adults. Reliability was established by using the test-retest method. A supervisory rating was developed and the reliability established by using the split-half…

Validating the Alcohol Use Disorders Identification Test with Persons Who Have a Serious Mental Illness

ERIC Educational Resources Information Center

O'Hare, Thomas; Sherrer, Margaret V.; LaButti, Annamaria; Emrick, Kelly

2004-01-01

Objective/Method: The use of brief, reliable, valid, and practical measures of substance use is critical for conducting individual assessments and program evaluation for integrated mental health-substance abuse services for persons with serious mental illness. This investigation examines the internal consistency reliability, concurrent validity,…

Measurement of Dietary Restraint: Validity Tests of Four Questionnaires

PubMed Central

Williamson, Donald A.; Martin, Corby K.; York-Crowe, Emily; Anton, Stephen D.; Redman, Leanne M.; Han, Hongmei; Ravussin, Eric

2007-01-01

This study tested the validity of four measures of dietary restraint: Dutch Eating Behavior Questionnaire, Eating Inventory (EI), Revised Restraint Scale (RS), and the Current Dieting Questionnaire. Dietary restraint has been implicated as a determinant of overeating and binge eating. Conflicting findings have been attributed to different methods for measuring dietary restraint. The validity of four self-report measures of dietary restraint and dieting behavior was tested using: 1) factor analysis, 2) changes in dietary restraint in a randomized controlled trial of different methods to achieve calorie restriction, and 3) correlation of changes in dietary restraint with an objective measure of energy balance, calculated from the changes in fat mass and fat-free mass over a six-month dietary intervention. Scores from all four questionnaires, measured at baseline, formed a dietary restraint factor, but the RS also loaded on a binge eating factor. Based on change scores, the EI Restraint scale was the only measure that correlated significantly with energy balance expressed as a percentage of energy require d for weight maintenance. These findings suggest that that, of the four questionnaires tested, the EI Restraint scale was the most valid measure of the intent to diet and actual caloric restriction. PMID:17101191

Validation of Physics Standardized Test Items

NASA Astrophysics Data System (ADS)

Marshall, Jill

2008-10-01

The Texas Physics Assessment Team (TPAT) examined the Texas Assessment of Knowledge and Skills (TAKS) to determine whether it is a valid indicator of physics preparation for future course work and employment, and of the knowledge and skills needed to act as an informed citizen in a technological society. We categorized science items from the 2003 and 2004 10th and 11th grade TAKS by content area(s) covered, knowledge and skills required to select the correct answer, and overall quality. We also analyzed a 5000 student sample of item-level results from the 2004 11th grade exam using standard statistical methods employed by test developers (factor analysis and Item Response Theory). Triangulation of our results revealed strengths and weaknesses of the different methods of analysis. The TAKS was found to be only weakly indicative of physics preparation and we make recommendations for increasing the validity of standardized physics testing..

Reconstruction and analysis of cesium-137 fallout deposition patterns in the Marshall Islands

NASA Astrophysics Data System (ADS)

Whitcomb, Robert Cleckley, Jr.

Estimates of 137Cs deposition due to fallout originating from nuclear weapons testing in the Marshall Islands have been made for several locations in the Marshall Islands. These retrospective estimates were based primarily on historical exposure rate and gummed film measurements. The methods used to reconstruct these deposition estimates are specific for six of the Pacific tests. These methods are also similar to those used in the National Cancer Institute study for reconstructing 131I deposition from the Nevada Test Site. Reconstructed cumulative deposition estimates are validated against contemporary measurements of 137Cs concentration in soil. This validation work also includes an accounting for estimated global fallout contributions. These validations show that the overall geometric bias in predicted-to-observed (P/O) ratios is 1.0 (indicating excellent agreement). The 5th and 95th percentile range of this distribution is 0.35--2.95. The P/O ratios for estimates using historical gummed film measurements tend to slightly over-predict more than estimates using exposure rate measurements. The methods produce reasonable estimates of deposition confirming that radioactive fallout occurred at atolls further south of the four northern atolls recognized by the Department of Energy as being affected by fallout. The deposition estimate methods, supported by the very good agreement between estimates and measurements, suggest that these methods can be used for other weapons testing fallout radionuclides with confidence.

New clinical validation method for automated sphygmomanometer: a proposal by Japan ISO-WG for sphygmomanometer standard.

PubMed

Shirasaki, Osamu; Asou, Yosuke; Takahashi, Yukio

2007-12-01

Owing to fast or stepwise cuff deflation, or measuring at places other than the upper arm, the clinical accuracy of most recent automated sphygmomanometers (auto-BPMs) cannot be validated by one-arm simultaneous comparison, which would be the only accurate validation method based on auscultation. Two main alternative methods are provided by current standards, that is, two-arm simultaneous comparison (method 1) and one-arm sequential comparison (method 2); however, the accuracy of these validation methods might not be sufficient to compensate for the suspicious accuracy in lateral blood pressure (BP) differences (LD) and/or BP variations (BPV) between the device and reference readings. Thus, the Japan ISO-WG for sphygmomanometer standards has been studying a new method that might improve validation accuracy (method 3). The purpose of this study is to determine the appropriateness of method 3 by comparing immunity to LD and BPV with those of the current validation methods (methods 1 and 2). The validation accuracy of the above three methods was assessed in human participants [N=120, 45+/-15.3 years (mean+/-SD)]. An oscillometric automated monitor, Omron HEM-762, was used as the tested device. When compared with the others, methods 1 and 3 showed a smaller intra-individual standard deviation of device error (SD1), suggesting their higher reproducibility of validation. The SD1 by method 2 (P=0.004) significantly correlated with the participant's BP, supporting our hypothesis that the increased SD of device error by method 2 is at least partially caused by essential BPV. Method 3 showed a significantly (P=0.0044) smaller interparticipant SD of device error (SD2), suggesting its higher interparticipant consistency of validation. Among the methods of validation of the clinical accuracy of auto-BPMs, method 3, which showed the highest reproducibility and highest interparticipant consistency, can be proposed as being the most appropriate.

AOAC Official MethodSM Matrix Extension Validation Study of Assurance GDSTM for the Detection of Salmonella in Selected Spices.

PubMed

Feldsine, Philip; Kaur, Mandeep; Shah, Khyati; Immerman, Amy; Jucker, Markus; Lienau, Andrew

2015-01-01

Assurance GDSTM for Salmonella Tq has been validated according to the AOAC INTERNATIONAL Methods Committee Guidelines for Validation of Microbiological Methods for Food and Environmental Surfaces for the detection of selected foods and environmental surfaces (Official Method of AnalysisSM 2009.03, Performance Tested MethodSM No. 050602). The method also completed AFNOR validation (following the ISO 16140 standard) compared to the reference method EN ISO 6579. For AFNOR, GDS was given a scope covering all human food, animal feed stuff, and environmental surfaces (Certificate No. TRA02/12-01/09). Results showed that Assurance GDS for Salmonella (GDS) has high sensitivity and is equivalent to the reference culture methods for the detection of motile and non-motile Salmonella. As part of the aforementioned validations, inclusivity and exclusivity studies, stability, and ruggedness studies were also conducted. Assurance GDS has 100% inclusivity and exclusivity among the 100 Salmonella serovars and 35 non-Salmonella organisms analyzed. To add to the scope of the Assurance GDS for Salmonella method, a matrix extension study was conducted, following the AOAC guidelines, to validate the application of the method for selected spices, specifically curry powder, cumin powder, and chili powder, for the detection of Salmonella.

Comparison effectiveness of cooperative learning type STAD with cooperative learning type TPS in terms of mathematical method of Junior High School students

NASA Astrophysics Data System (ADS)

Wahyuni, A.

2018-05-01

This research is aimed to find out whether the model of cooperative learning type Student Team Achievement Division (STAD) is more effective than cooperative learning type Think-Pair-Share in SMP Negeri 7 Yogyakarta. This research was a quasi-experimental research, using two experimental groups. The population of research was all students of 7thclass in SMP Negeri 7 Yogyakarta that consists of 5 Classes. From the population were taken 2 classes randomly which used as sample. The instrument to collect data was a description test. Measurement of instrument validity use content validity and construct validity, while measuring instrument reliability use Cronbach Alpha formula. To investigate the effectiveness of cooperative learning type STAD and cooperative learning type TPS on the aspect of student’s mathematical method, the datas were analyzed by one sample test. Comparing the effectiveness of cooperative learning type STAD and TPS in terms of mathematical communication skills by using t-test. Normality test was not conducted because the sample of research more than 30 students, while homogeneity tested by using Kolmogorov Smirnov test. The analysis was performed at 5% confidence level.The results show as follows : 1) The model of cooperative learning type STAD and TPS are effective in terms of mathematical method of junior high school students. 2). STAD type cooperative learning model is more effective than TPS type cooperative learning model in terms of mathematical methods of junior high school students.

Construct Validity of the Emotional Eating Scale Adapted for Children and Adolescents

PubMed Central

Vannucci, Anna; Tanofsky-Kraff, Marian; Shomaker, Lauren B.; Ranzenhofer, Lisa M.; Matheson, Brittany E.; Cassidy, Omni L.; Zocca, Jaclyn M.; Kozlosky, Merel; Yanovski, Susan Z.; Yanovski, Jack A.

2012-01-01

Background Emotional eating, defined as eating in response to a range of negative emotions, is common in youth. Yet, there are few easily administered and well-validated methods to assess emotional eating in pediatric populations. Objective The current study tested the construct validity of the Emotional Eating Scale Adapted for Children and Adolescents (EES-C) by examining its relationship to observed emotional eating at laboratory test meals. Method One hundred fifty-one youth (8-18 years) participated in two multi-item lunch buffet meals on separate days. They ate ad libitum after being instructed to “eat as much as you would at a normal meal” or to “let yourself go and eat as much as you want.” State negative affect was assessed immediately prior to each meal. The EES-C was completed three months, on average, prior to the first test meal. Results Among youth with high EES-C total scores, but not low EES-C scores, higher pre-meal state negative affect was related to greater total energy intake at both meals, with and without the inclusion of age, race, sex, and BMI-z as covariates (ps < 0.03). Discussion The EES-C demonstrates good construct validity for children and adolescents’ observed energy intake across laboratory test meals designed to capture both normal and disinhibited eating. Future research is required to evaluate the construct validity of the EES-C in the natural environment and the predictive validity of the EES-C longitudinally. PMID:22124451

Optimal Combinations of Diagnostic Tests Based on AUC.

PubMed

Huang, Xin; Qin, Gengsheng; Fang, Yixin

2011-06-01

When several diagnostic tests are available, one can combine them to achieve better diagnostic accuracy. This article considers the optimal linear combination that maximizes the area under the receiver operating characteristic curve (AUC); the estimates of the combination's coefficients can be obtained via a nonparametric procedure. However, for estimating the AUC associated with the estimated coefficients, the apparent estimation by re-substitution is too optimistic. To adjust for the upward bias, several methods are proposed. Among them the cross-validation approach is especially advocated, and an approximated cross-validation is developed to reduce the computational cost. Furthermore, these proposed methods can be applied for variable selection to select important diagnostic tests. The proposed methods are examined through simulation studies and applications to three real examples. © 2010, The International Biometric Society.

Validity of Bioelectrical Impedance Analysis to Estimation Fat-Free Mass in the Army Cadets.

PubMed

Langer, Raquel D; Borges, Juliano H; Pascoa, Mauro A; Cirolini, Vagner X; Guerra-Júnior, Gil; Gonçalves, Ezequiel M

2016-03-11

Bioelectrical Impedance Analysis (BIA) is a fast, practical, non-invasive, and frequently used method for fat-free mass (FFM) estimation. The aims of this study were to validate predictive equations of BIA to FFM estimation in Army cadets and to develop and validate a specific BIA equation for this population. A total of 396 males, Brazilian Army cadets, aged 17-24 years were included. The study used eight published predictive BIA equations, a specific equation in FFM estimation, and dual-energy X-ray absorptiometry (DXA) as a reference method. Student's t-test (for paired sample), linear regression analysis, and Bland-Altman method were used to test the validity of the BIA equations. Predictive BIA equations showed significant differences in FFM compared to DXA (p < 0.05) and large limits of agreement by Bland-Altman. Predictive BIA equations explained 68% to 88% of FFM variance. Specific BIA equations showed no significant differences in FFM, compared to DXA values. Published BIA predictive equations showed poor accuracy in this sample. The specific BIA equations, developed in this study, demonstrated validity for this sample, although should be used with caution in samples with a large range of FFM.

Predicting psychopharmacological drug effects on actual driving performance (SDLP) from psychometric tests measuring driving-related skills.

PubMed

Verster, Joris C; Roth, Thomas

2012-03-01

There are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined. The objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic. Ninety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a constant speed and steady lateral position within the right traffic lane. Standard deviation of lateral position (SDLP), i.e., the weaving of the car, was determined. The subjects also performed a psychometric test battery including the DSST, Sternberg memory scanning test, a tracking test, and a divided attention test. Difference scores from placebo for parameters of the psychometric tests and SDLP were computed and correlated with each other. A stepwise linear regression analysis determined the predictive validity of the laboratory test battery to SDLP. Stepwise regression analyses revealed that the combination of five parameters, hard tracking, tracking and reaction time of the divided attention test, and reaction time and percentage of errors of the Sternberg memory scanning test, together had a predictive validity of 33.4%. The psychometric tests in this test battery showed insufficient predictive validity to replace the on-the-road driving test during normal traffic.

The reliability and validity of the SF-8 with a conflict-affected population in northern Uganda

PubMed Central

Roberts, Bayard; Browne, John; Ocaka, Kaducu Felix; Oyok, Thomas; Sondorp, Egbert

2008-01-01

Background The SF-8 is a health-related quality of life instrument that could provide a useful means of assessing general physical and mental health amongst populations affected by conflict. The purpose of this study was to test the validity and reliability of the SF-8 with a conflict-affected population in northern Uganda. Methods A cross-sectional multi-staged, random cluster survey was conducted with 1206 adults in camps for internally displaced persons in Gulu and Amuru districts of northern Uganda. Data quality was assessed by analysing the number of incomplete responses to SF-8 items. Response distribution was analysed using aggregate endorsement frequency. Test-retest reliability was assessed in a separate smaller survey using the intraclass correlation test. Construct validity was measured using principal component analysis, and the Pearson Correlation test for item-summary score correlation and inter-instrument correlations. Known groups validity was assessed using a two sample t-test to evaluates the ability of the SF-8 to discriminate between groups known to have, and not have, physical and mental health problems. Results The SF-8 showed excellent data quality. It showed acceptable item response distribution based upon analysis of aggregate endorsement frequencies. Test-retest showed a good intraclass correlation of 0.61 for PCS and 0.68 for MCS. The principal component analysis indicated strong construct validity and concurred with the results of the validity tests by the SF-8 developers. The SF-8 also showed strong construct validity between the 8 items and PCS and MCS summary score, moderate inter-instrument validity, and strong known groups validity. Conclusion This study provides evidence on the reliability and validity of the SF-8 amongst IDPs in northern Uganda. PMID:19055716

TESTING BALANCE AND FALL RISK IN PERSONS WITH PARKINSON DISEASE, AN ARGUMENT FOR ECOLOGICALLY VALID TESTING

PubMed Central

Foreman, K. Bo; Addison, Odessa; Kim, Han S.; Dibble, Leland E.

2010-01-01

Introduction Despite clear deficits in postural control, most clinical examination tools lack accuracy in identifying persons with Parkinson disease (PD) who have fallen or are at risk for falls. We assert that this is in part due to the lack of ecological validity of the testing. Methods To test this assertion, we examined the responsiveness and predictive validity of the Functional Gait Assessment (FGA), the Pull test, and the Timed up and Go (TUG) during clinically defined ON and OFF medication states. To address responsiveness, ON/OFF medication performance was compared. To address predictive validity, areas under the curve (AUC) of receiver operating characteristic (ROC) curves were compared. Comparisons were made using separate non-parametric tests. Results Thirty-six persons (24 male, 12 female) with PD (22 fallers, 14 non-fallers) participated. Only the FGA was able to detect differences between fallers and non-fallers for both ON/OFF medication testing. The predictive validity of the FGA and the TUG for fall identification was higher during OFF medication compared to ON medication testing. The predictive validity of the FGA was higher than the TUG and the Pull test during ON and OFF medication testing. Discussion In order to most accurately identify fallers, clinicians should test persons with PD in ecologically relevant conditions and tasks. In this study, interpretation of the OFF medication performance and use of the FGA provided more accurate prediction of those who would fall. PMID:21215674

Development and validation of challenge materials for double-blind, placebo-controlled food challenges in children.

PubMed

Vlieg-Boerstra, Berber J; Bijleveld, Charles M A; van der Heide, Sicco; Beusekamp, Berta J; Wolt-Plompen, Saskia A A; Kukler, Jeanet; Brinkman, Joep; Duiverman, Eric J; Dubois, Anthony E J

2004-02-01

The use of double-blind, placebo-controlled food challenges (DBPCFCs) is considered the gold standard for the diagnosis of food allergy. Despite this, materials and methods used in DBPCFCs have not been standardized. The purpose of this study was to develop and validate recipes for use in DBPCFCs in children by using allergenic foods, preferably in their usual edible form. Recipes containing milk, soy, cooked egg, raw whole egg, peanut, hazelnut, and wheat were developed. For each food, placebo and active test food recipes were developed that met the requirements of acceptable taste, allowance of a challenge dose high enough to elicit reactions in an acceptable volume, optimal matrix ingredients, and good matching of sensory properties of placebo and active test food recipes. Validation was conducted on the basis of sensory tests for difference by using the triangle test and the paired comparison test. Recipes were first tested by volunteers from the hospital staff and subsequently by a professional panel of food tasters in a food laboratory designed for sensory testing. Recipes were considered to be validated if no statistically significant differences were found. Twenty-seven recipes were developed and found to be valid by the volunteer panel. Of these 27 recipes, 17 could be validated by the professional panel. Sensory testing with appropriate statistical analysis allows for objective validation of challenge materials. We recommend the use of professional tasters in the setting of a food laboratory for best results.

Evaluation of the Thermo Scientific™ SureTect™ Salmonella species Assay.

PubMed

Cloke, Jonathan; Clark, Dorn; Radcliff, Roy; Leon-Velarde, Carlos; Larson, Nathan; Dave, Keron; Evans, Katharine; Crabtree, David; Hughes, Annette; Simpson, Helen; Holopainen, Jani; Wickstrand, Nina; Kauppinen, Mikko

2014-03-01

The Thermo Scientific™ SureTect™ Salmonella species Assay is a new real-time PCR assay for the detection of Salmonellae in food and environmental samples. This validation study was conducted using the AOAC Research Institute (RI) Performance Tested MethodsSM program to validate the SureTect Salmonella species Assay in comparison to the reference method detailed in International Organization for Standardization 6579:2002 in a variety of food matrixes, namely, raw ground beef, raw chicken breast, raw ground pork, fresh bagged lettuce, pork frankfurters, nonfat dried milk powder, cooked peeled shrimp, pasteurized liquid whole egg, ready-to-eat meal containing beef, and stainless steel surface samples. With the exception of liquid whole egg and fresh bagged lettuce, which were tested in-house, all matrixes were tested by Marshfield Food Safety, Marshfield, WI, on behalf of Thermo Fisher Scientific. In addition, three matrixes (pork frankfurters, lettuce, and stainless steel surface samples) were analyzed independently as part of the AOAC-RI-controlled laboratory study by the University of Guelph, Canada. No significant difference by probability of detection or McNemars Chi-squared statistical analysis was found between the candidate or reference methods for any of the food matrixes or environmental surface samples tested during the validation study. Inclusivity and exclusivity testing was conducted with 117 and 36 isolates, respectively, which demonstrated that the SureTect Salmonella species Assay was able to detect all the major groups of Salmonella enterica subspecies enterica (e.g., Typhimurium) and the less common subspecies of S. enterica (e.g., arizoniae) and the rarely encountered S. bongori. None of the exclusivity isolates analyzed were detected by the SureTect Salmonella species Assay. Ruggedness testing was conducted to evaluate the performance of the assay with specific method deviations outside of the recommended parameters open to variation (enrichment time and temperature, and lysis temperature), which demonstrated that the assay gave reliable performance. Accelerated stability testing was additionally conducted, validating the assay shelf life.

The predictive value of the sacral base pressure test in detecting specific types of sacroiliac dysfunction

PubMed Central

Mitchell, Travis D.; Urli, Kristina E.; Breitenbach, Jacques; Yelverton, Chris

2007-01-01

Abstract Objective This study aimed to evaluate the validity of the sacral base pressure test in diagnosing sacroiliac joint dysfunction. It also determined the predictive powers of the test in determining which type of sacroiliac joint dysfunction was present. Methods This was a double-blind experimental study with 62 participants. The results from the sacral base pressure test were compared against a cluster of previously validated tests of sacroiliac joint dysfunction to determine its validity and predictive powers. The external rotation of the feet, occurring during the sacral base pressure test, was measured using a digital inclinometer. Results There was no statistically significant difference in the results of the sacral base pressure test between the types of sacroiliac joint dysfunction. In terms of the results of validity, the sacral base pressure test was useful in identifying positive values of sacroiliac joint dysfunction. It was fairly helpful in correctly diagnosing patients with negative test results; however, it had only a “slight” agreement with the diagnosis for κ interpretation. Conclusions In this study, the sacral base pressure test was not a valid test for determining the presence of sacroiliac joint dysfunction or the type of dysfunction present. Further research comparing the agreement of the sacral base pressure test or other sacroiliac joint dysfunction tests with a criterion standard of diagnosis is necessary. PMID:19674694

The predictive validity of selection for entry into postgraduate training in general practice: evidence from three longitudinal studies

PubMed Central

Patterson, Fiona; Lievens, Filip; Kerrin, Máire; Munro, Neil; Irish, Bill

2013-01-01

Background The selection methodology for UK general practice is designed to accommodate several thousand applicants per year and targets six core attributes identified in a multi-method job-analysis study Aim To evaluate the predictive validity of selection methods for entry into postgraduate training, comprising a clinical problem-solving test, a situational judgement test, and a selection centre. Design and setting A three-part longitudinal predictive validity study of selection into training for UK general practice. Method In sample 1, participants were junior doctors applying for training in general practice (n = 6824). In sample 2, participants were GP registrars 1 year into training (n = 196). In sample 3, participants were GP registrars sitting the licensing examination after 3 years, at the end of training (n = 2292). The outcome measures include: assessor ratings of performance in a selection centre comprising job simulation exercises (sample 1); supervisor ratings of trainee job performance 1 year into training (sample 2); and licensing examination results, including an applied knowledge examination and a 12-station clinical skills objective structured clinical examination (OSCE; sample 3). Results Performance ratings at selection predicted subsequent supervisor ratings of job performance 1 year later. Selection results also significantly predicted performance on both the clinical skills OSCE and applied knowledge examination for licensing at the end of training. Conclusion In combination, these longitudinal findings provide good evidence of the predictive validity of the selection methods, and are the first reported for entry into postgraduate training. Results show that the best predictor of work performance and training outcomes is a combination of a clinical problem-solving test, a situational judgement test, and a selection centre. Implications for selection methods for all postgraduate specialties are considered. PMID:24267856

Crucial aspects of high performance thin layer chromatography quantitative validation. The case of determination of rosmarinic acid in different matrices.

PubMed

Coran, Silvia A; Mulas, Stefano; Mulinacci, Nadia

2012-01-13

A new HPTLC method was envisaged to determine rosmarinic acid (RA) in different matrices with the aim of testing the influence of optimizing the main HPTLC operative parameters in view of a more stringent validation process. HPTLC LiChrospher silica gel 60 F254s, 20 cm × 10 cm, plates with toluene:ethyl formate:formic acid (6:4:1, v/v) as the mobile phase were used. Densitometric determinations were performed in reflectance mode at 330 nm. The method was validated giving rise to a dependable and high throughput procedure well suited to routine applications. RA was quantified in the range of 132-660 ng with RSD of repeatability and intermediate precision not exceeding 2.0% and accuracy within the acceptance limits. The method was tested on several commercial preparations containing RA in different amounts. Copyright © 2011 Elsevier B.V. All rights reserved.

Domestic violence on children: development and validation of an instrument to evaluate knowledge of health professionals 1

PubMed Central

Oliveira, Lanuza Borges; Soares, Fernanda Amaral; Silveira, Marise Fagundes; de Pinho, Lucinéia; Caldeira, Antônio Prates; Leite, Maísa Tavares de Souza

2016-01-01

ABSTRACT Objective: to develop and validate an instrument to evaluate the knowledge of health professionals about domestic violence on children. Method: this was a study conducted with 194 physicians, nurses and dentists. A literature review was performed for preparation of the items and identification of the dimensions. Apparent and content validation was performed using analysis of three experts and 27 professors of the pediatric health discipline. For construct validation, Cronbach's alpha was used, and the Kappa test was applied to verify reproducibility. The criterion validation was conducted using the Student's t-test. Results: the final instrument included 56 items; the Cronbach alpha was 0.734, the Kappa test showed a correlation greater than 0.6 for most items, and the Student t-test showed a statistically significant value to the level of 5% for the two selected variables: years of education and using the Family Health Strategy. Conclusion: the instrument is valid and can be used as a promising tool to develop or direct actions in public health and evaluate knowledge about domestic violence on children. PMID:27556878

Creating a flipbook as a medium of instruction based on the research on activity test of kencur extract

NASA Astrophysics Data System (ADS)

Monika, Icha; Yeni, Laili Fitri; Ariyati, Eka

2016-02-01

This research aimed to reveal the validity of the flipbook as a medium of learning for the sub-material of environmental pollution in the tenth grade based on the results of the activity test of kencur (Kaempferia galanga) extract to control the growth of the Fusarium oxysporum fungus. The research consisted of two stages. First, testing the validity of the medium of flipbook through validation by seven assessors and analyzed based on the total average score of all aspects. Second, testing the activity of the kencur extract against the growth of Fusarium oxysporum by using the experimental method with 10 treatments and 3 repetitions which were analyzed using one-way analysis of variance (ANOVA) test. The making of the flipbook medium was done through the stages of analysis for the potential and problems, data collection, design, validation, and revision. The validation analysis on the flipbook received an average score of 3.7 and was valid to a certain extent, so it could be used in the teaching and learning process especially in the sub-material of environmental pollution in the tenth grade of the senior high school.

Screening for colon cancer: A test for occult blood.

PubMed

Khakimov, N; Khasanova, G; Ershova, K; Gibadullina, L; Vetkina, T; Lobisheva, G; Chumakova, A

2015-01-01

The relevance of the problem of colorectal cancer (CRC) is evident because of extremely high morbidity and mortality rates, associated with this disease. CRC is mostly diagnosed only at very advanced stages. The reduction of mortality can be achieved by the popularization of screening-methods for early identification of CRC and adenomatous polyps of the colon, which are proved to be precancerous condition. Fecal occult blood test is a well-known method of screening for CRC. The advantages of this method when compared, for example, with colonoscopy are its simplicity and cost-effectiveness.Two techniques are usually used for detection of occult blood in the stool: Hemoccult (Guaiac) test and immunochemical test for hemoglobin. There is no consensus among researchers regarding the validity of these tests for the diagnosis of colorectal cancer. For example, J.S. Mandel (1996) notes 60% sensitivity of Guaiac-test for the detection of the early forms of colorectal cancer, while O.I. Kit (2014) suggets that it is not higher than 30%. There are also various opinions about specificity of these two tests. To review the literature on the validity of the fecal occult blood tests for the diagnosis of CRC. We looked for articles (electronic versions) available for free in the full-text versions, published from June 1, 1990 to December 31, 2014 in Russian or English. The following databases were used for search: E-LIBRARY; Cochrane; MEDLINE; EMBASE; Google search. Only original research papers were analyzed. Literature reviews or systematic reviews were not taken for analyses. 1) use of Guaiac and/or immunochemical fecal occult blood test as screening-tests for the detection of colorectal cancer and/or colon polyps (1 cm or more in diameter) in people older than 45 years; 2) comparing of results with the results of colonoscopy (colonoscopy is counted by majority of the authors as a "gold standard" for the diagnosis of CRC and adenomatous polyps). Initial keyword search returned 803 000 results, of which 449 sources were selected. After reading the abstracts, 29 articles that met inclusion criteria were kept. 10 other articles were excluded after that because they did not contain enough data for extraction or did not contain a control group. At the final step 19 articles were used for meta-analysis.Forest plot and Rock curve, which were developed with inclusion of the data from all studies, showed heterogeneity of the data. Additional analyzes were performed in subgroups with different diagnoses and various tests.The sensitivity of the Guaiac test for the diagnosis of colorectal cancer varied from 0.13 to 1.00, and specificity - from 0.69 to 0.99. The sensitivity of the immunochemical test for the diagnosis of CRC ranged from 0.42 to 0.94 with specificity ranging from 0.40 to 1.00.The sensitivity of the Guaiac test for the diagnosis of the colon polyps was between 0.05 and 0.69, and its specificity - from 0.67 to 0.98. The sensitivity of the immunochemical test for the diagnosis of polyps was from 0.24 to 0.75, and its specificity - from 0.40 to 0.97.Bivariate analysis of the validity of Guaiac test and immunochemical method for the diagnosis of colorectal cancer showed better results for the immunochemical test compared to Guaiac test. The tests showed very similar results when used for the diagnosis of polyposis. Bivariate analysis, comparing the validity of tests for the diagnosis of colorectal cancer versus polyposis demonstrated better results for CRC.Multivariate analysis of the validity of the Guaiac and immunochemical tests for the diagnosis of colorectal cancer and polyps also showed better results for detection of colorectal cancer compared with the polyps for both tests. At the same time the highest validity for the diagnosis of CRC was demonstrated for immunochemical analysis. 1. The sensitivity of the Guaiac test for occult blood in stool is lower than its specificity.2. Broad dispersion of the validity characteristics of the fecal occult blood tests was observed.3. The validity of tests for occult blood was higher when they were used for detection of colorectal cancer than of colon polyposis.4. The highest validity rate has been demonstrated for the immunochemical test when it was used for colon cancer screening.

Implementation and Validation of an Impedance Eduction Technique

NASA Technical Reports Server (NTRS)

Watson, Willie R.; Jones, Michael G.; Gerhold, Carl H.

2011-01-01

Implementation of a pressure gradient method of impedance eduction in two NASA Langley flow ducts is described. The Grazing Flow Impedance Tube only supports plane-wave sources, while the Curved Duct Test Rig supports sources that contain higher-order modes. Multiple exercises are used to validate this new impedance eduction method. First, synthesized data for a hard wall insert and a conventional liner mounted in the Grazing Flow Impedance Tube are used as input to the two impedance eduction methods, the pressure gradient method and a previously validated wall pressure method. Comparisons between the two results are excellent. Next, data measured in the Grazing Flow Impedance Tube are used as input to both methods. Results from the two methods compare quite favorably for sufficiently low Mach numbers but this comparison degrades at Mach 0.5, especially when the hard wall insert is used. Finally, data measured with a hard wall insert mounted in the Curved Duct Test Rig are used as input to the pressure gradient method. Significant deviation from the known solution is observed, which is believed to be largely due to 3-D effects in this flow duct. Potential solutions to this issue are currently being explored.

An Efficient Data Partitioning to Improve Classification Performance While Keeping Parameters Interpretable

PubMed Central

Korjus, Kristjan; Hebart, Martin N.; Vicente, Raul

2016-01-01

Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier’s generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term “Cross-validation and cross-testing” improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do. PMID:27564393

Validated spectrofluorimetric method for determination of two phosphodiesterase inhibitors tadalafil and vardenafil in pharmaceutical preparations and spiked human plasma.

PubMed

Abu El-Enin, Mohammed Abu Bakr; Al-Ghaffar Hammouda, Mohammed El-Sayed Abd; El-Sherbiny, Dina Tawfik; El-Wasseef, Dalia Rashad; El-Ashry, Saadia Mahmoud

2016-02-01

A valid, sensitive and rapid spectrofluorimetric method has been developed and validated for determination of both tadalafil (TAD) and vardenafil (VAR) either in their pure form, in their tablet dosage forms or spiked in human plasma. This method is based on measurement of the native fluorescence of both drugs in acetonitrile at λem 330 and 470 nm after excitation at 280 and 275 nm for tadalafil and vardenafil, respectively. Linear relationships were obtained over the concentration range 4-40 and 10-250 ng/mL with a minimum detection of 1 and 3 ng/mL for tadalafil and vardenafil, respectively. Various experimental parameters affecting the fluorescence intensity were carefully studied and optimized. The developed method was applied successfully for the determination of tadalafil and vardenafil in bulk drugs and tablet dosage forms. Moreover, the high sensitivity of the proposed method permitted their determination in spiked human plasma. The developed method was validated in terms of specificity, linearity, lower limit of quantification (LOQ), lower limit of detection (LOD), precision and accuracy. The mean recoveries of the analytes in pharmaceutical preparations were in agreement with those obtained from the comparison methods, as revealed by statistical analysis of the obtained results using Student's t-test and the variance ratio F-test. Copyright © 2015 John Wiley & Sons, Ltd.

Patient simulation: a literary synthesis of assessment tools in anesthesiology.

PubMed

Edler, Alice A; Fanning, Ruth G; Chen, Michael I; Claure, Rebecca; Almazan, Dondee; Struyk, Brain; Seiden, Samuel C

2009-12-20

High-fidelity patient simulation (HFPS) has been hypothesized as a modality for assessing competency of knowledge and skill in patient simulation, but uniform methods for HFPS performance assessment (PA) have not yet been completely achieved. Anesthesiology as a field founded the HFPS discipline and also leads in its PA. This project reviews the types, quality, and designated purpose of HFPS PA tools in anesthesiology. We used the systematic review method and systematically reviewed anesthesiology literature referenced in PubMed to assess the quality and reliability of available PA tools in HFPS. Of 412 articles identified, 50 met our inclusion criteria. Seventy seven percent of studies have been published since 2000; more recent studies demonstrated higher quality. Investigators reported a variety of test construction and validation methods. The most commonly reported test construction methods included "modified Delphi Techniques" for item selection, reliability measurement using inter-rater agreement, and intra-class correlations between test items or subtests. Modern test theory, in particular generalizability theory, was used in nine (18%) of studies. Test score validity has been addressed in multiple investigations and shown a significant improvement in reporting accuracy. However the assessment of predicative has been low across the majority of studies. Usability and practicality of testing occasions and tools was only anecdotally reported. To more completely comply with the gold standards for PA design, both shared experience of experts and recognition of test construction standards, including reliability and validity measurements, instrument piloting, rater training, and explicit identification of the purpose and proposed use of the assessment tool, are required.

Quantitative determination and validation of octreotide acetate using 1 H-NMR spectroscopy with internal standard method.

PubMed

Yu, Chen; Zhang, Qian; Xu, Peng-Yao; Bai, Yin; Shen, Wen-Bin; Di, Bin; Su, Meng-Xiang

2018-01-01

Quantitative nuclear magnetic resonance (qNMR) is a well-established technique in quantitative analysis. We presented a validated 1 H-qNMR method for assay of octreotide acetate, a kind of cyclic octopeptide. Deuterium oxide was used to remove the undesired exchangeable peaks, which was referred to as proton exchange, in order to make the quantitative signals isolated in the crowded spectrum of the peptide and ensure precise quantitative analysis. Gemcitabine hydrochloride was chosen as the suitable internal standard. Experimental conditions, including relaxation delay time, the numbers of scans, and pulse angle, were optimized first. Then method validation was carried out in terms of selectivity, stability, linearity, precision, and robustness. The assay result was compared with that by means of high performance liquid chromatography, which is provided by Chinese Pharmacopoeia. The statistical F test, Student's t test, and nonparametric test at 95% confidence level indicate that there was no significant difference between these two methods. qNMR is a simple and accurate quantitative tool with no need for specific corresponding reference standards. It has the potential of the quantitative analysis of other peptide drugs and standardization of the corresponding reference standards. Copyright © 2017 John Wiley & Sons, Ltd.

METAPHOR: Probability density estimation for machine learning based photometric redshifts

NASA Astrophysics Data System (ADS)

Amaro, V.; Cavuoti, S.; Brescia, M.; Vellucci, C.; Tortora, C.; Longo, G.

2017-06-01

We present METAPHOR (Machine-learning Estimation Tool for Accurate PHOtometric Redshifts), a method able to provide a reliable PDF for photometric galaxy redshifts estimated through empirical techniques. METAPHOR is a modular workflow, mainly based on the MLPQNA neural network as internal engine to derive photometric galaxy redshifts, but giving the possibility to easily replace MLPQNA with any other method to predict photo-z's and their PDF. We present here the results about a validation test of the workflow on the galaxies from SDSS-DR9, showing also the universality of the method by replacing MLPQNA with KNN and Random Forest models. The validation test include also a comparison with the PDF's derived from a traditional SED template fitting method (Le Phare).

Validity and reliability of the Myotest accelerometric system for the assessment of vertical jump height.

PubMed

Casartelli, Nicola; Müller, Roland; Maffiuletti, Nicola A

2010-11-01

The aim of the present study was to verify the validity and reliability of the Myotest accelerometric system (Myotest SA, Sion, Switzerland) for the assessment of vertical jump height. Forty-four male basketball players (age range: 9-25 years) performed series of squat, countermovement and repeated jumps during 2 identical test sessions separated by 2-15 days. Flight height was simultaneously quantified with the Myotest system and validated photoelectric cells (Optojump). Two calculation methods were used to estimate the jump height from Myotest recordings: flight time (Myotest-T) and vertical takeoff velocity (Myotest-V). Concurrent validity was investigated comparing Myotest-T and Myotest-V to the criterion method (Optojump), and test-retest reliability was also examined. As regards validity, Myotest-T overestimated jumping height compared to Optojump (p < 0.001) with a systematic bias of approximately 7 cm, even though random errors were low (2.7 cm) and intraclass correlation coefficients (ICCs) where high (>0.98), that is, excellent validity. Myotest-V overestimated jumping height compared to Optojump (p < 0.001), with high random errors (>12 cm), high limits of agreement ratios (>36%), and low ICCs (<0.75), that is, poor validity. As regards reliability, Myotest-T showed high ICCs (range: 0.92-0.96), whereas Myotest-V showed low ICCs (range: 0.56-0.89), and high random errors (>9 cm). In conclusion, Myotest-T is a valid and reliable method for the assessment of vertical jump height, and its use is legitimate for field-based evaluations, whereas Myotest-V is neither valid nor reliable.

Inter-Disciplinary Collaboration in Support of the Post-Standby TREAT Mission

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeHart, Mark; Baker, Benjamin; Ortensi, Javier

Although analysis methods have advanced significantly in the last two decades, high fidelity multi- physics methods for reactors systems have been under development for only a few years and are not presently mature nor deployed. Furthermore, very few methods provide the ability to simulate rapid transients in three dimensions. Data for validation of advanced time-dependent multi- physics is sparse; at TREAT, historical data were not collected for the purpose of validating three-dimensional methods, let alone multi-physics simulations. Existing data continues to be collected to attempt to simulate the behavior of experiments and calibration transients, but it will be insufficient formore » the complete validation of analysis methods used for TREAT transient simulations. Hence, a 2018 restart will most likely occur without the direct application of advanced modeling and simulation methods. At present, the current INL modeling and simulation team plans to work with TREAT operations staff in performing reactor simulations with MAMMOTH, in parallel with the software packages currently being used in preparation for core restart (e.g., MCNP5, RELAP5, ABAQUS). The TREAT team has also requested specific measurements to be performed during startup testing, currently scheduled to run from February to August of 2018. These startup measurements will be crucial in validating the new analysis methods in preparation for ultimate application for TREAT operations and experiment design. This document describes the collaboration between modeling and simulation staff and restart, operations, instrumentation and experiment development teams to be able to effectively interact and achieve successful validation work during restart testing.« less

The validation of science virtual test to assess 7th grade students’ critical thinking on matter and heat topic (SVT-MH)

NASA Astrophysics Data System (ADS)

Sya’bandari, Y.; Firman, H.; Rusyati, L.

2018-05-01

The method used in this research was descriptive research for profiling the validation of SVT-MH to measure students’ critical thinking on matter and heat topic in junior high school. The subject is junior high school students of 7th grade (13 years old) while science teacher and expert as the validators. The instruments that used as a tool to obtain the data are rubric expert judgment (content, media, education) and rubric of readability test. There are four steps to validate SVT-MH in 7th grade Junior High School. These steps are analysis of core competence and basic competence based on Curriculum 2013, expert judgment (content, media, education), readability test and trial test (limited and larger trial test). The instrument validation resulted 30 items that represent 8 elements and 21 sub-elements to measure students’ critical thinking based on Inch in matter and heat topic. The alpha Cronbach (α) is 0.642 which means that the instrument is sufficient to measure students’ critical thinking matter and heat topic.

Validity of self-reported mechanical demands for occupational epidemiologic research of musculoskeletal disorders

PubMed Central

Barrero, Lope H; Katz, Jeffrey N; Dennerlein, Jack T

2012-01-01

Objectives To describe the relation of the measured validity of self-reported mechanical demands (self-reports) with the quality of validity assessments and the variability of the assessed exposure in the study population. Methods We searched for original articles, published between 1990 and 2008, reporting the validity of self-reports in three major databases: EBSCOhost, Web of Science, and PubMed. Identified assessments were classified by methodological characteristics (eg, type of self-report and reference method) and exposure dimension was measured. We also classified assessments by the degree of comparability between the self-report and the employed reference method, and the variability of the assessed exposure in the study population. Finally, we examined the association of the published validity (r) with this degree of comparability, as well as with the variability of the exposure variable in the study population. Results Of the 490 assessments identified, 75% used observation-based reference measures and 55% tested self-reports of posture duration and movement frequency. Frequently, validity studies did not report demographic information (eg, education, age, and gender distribution). Among assessments reporting correlations as a measure of validity, studies with a better match between the self-report and the reference method, and studies conducted in more heterogeneous populations tended to report higher correlations [odds ratio (OR) 2.03, 95% confidence interval (95% CI) 0.89–4.65 and OR 1.60, 95% CI 0.96–2.61, respectively]. Conclusions The reported data support the hypothesis that validity depends on study-specific factors often not examined. Experimentally manipulating the testing setting could lead to a better understanding of the capabilities and limitations of self-reported information. PMID:19562235

Ranking of physiotherapeutic evaluation methods as outcome measures of stifle functionality in dogs.

PubMed

Hyytiäinen, Heli K; Mölsä, Sari H; Junnila, Jouni T; Laitinen-Vapaavuori, Outi M; Hielm-Björkman, Anna K

2013-04-08

Various physiotherapeutic evaluation methods are used to assess the functionality of dogs with stifle problems. Neither validity nor sensitivity of these methods has been investigated. This study aimed to determine the most valid and sensitive physiotherapeutic evaluation methods for assessing functional capacity in hind limbs of dogs with stifle problems and to serve as a basis for developing an indexed test for these dogs. A group of 43 dogs with unilateral surgically treated cranial cruciate ligament deficiency and osteoarthritic findings was used to test different physiotherapeutic evaluation methods. Twenty-one healthy dogs served as the control group and were used to determine normal variation in static weight bearing and range of motion.The protocol consisted of 14 different evaluation methods: visual evaluation of lameness, visual evaluation of diagonal movement, visual evaluation of functional active range of motion and difference in thrust of hind limbs via functional tests (sit-to-move and lie-to-move), movement in stairs, evaluation of hind limb muscle atrophy, manual evaluation of hind limb static weight bearing, quantitative measurement of static weight bearing of hind limbs with bathroom scales, and passive range of motion of hind limb stifle (flexion and extension) and tarsal (flexion and extension) joints using a universal goniometer. The results were compared with those from an orthopaedic examination, force plate analysis, radiographic evaluation, and a conclusive assessment. Congruity of the methods was assessed with a combination of three statistical approaches (Fisher's exact test and two differently calculated proportions of agreeing observations), and the components were ranked from best to worst. Sensitivities of all of the physiotherapeutic evaluation methods against each standard were calculated. Evaluation of asymmetry in a sitting and lying position, assessment of muscle atrophy, manual and measured static weight bearing, and measurement of stifle passive range of motion were the most valid and sensitive physiotherapeutic evaluation methods. Ranking of the various physiotherapeutic evaluation methods was accomplished. Several of these methods can be considered valid and sensitive when examining the functionality of dogs with stifle problems.

Ranking of physiotherapeutic evaluation methods as outcome measures of stifle functionality in dogs

PubMed Central

2013-01-01

Background Various physiotherapeutic evaluation methods are used to assess the functionality of dogs with stifle problems. Neither validity nor sensitivity of these methods has been investigated. This study aimed to determine the most valid and sensitive physiotherapeutic evaluation methods for assessing functional capacity in hind limbs of dogs with stifle problems and to serve as a basis for developing an indexed test for these dogs. A group of 43 dogs with unilateral surgically treated cranial cruciate ligament deficiency and osteoarthritic findings was used to test different physiotherapeutic evaluation methods. Twenty-one healthy dogs served as the control group and were used to determine normal variation in static weight bearing and range of motion. The protocol consisted of 14 different evaluation methods: visual evaluation of lameness, visual evaluation of diagonal movement, visual evaluation of functional active range of motion and difference in thrust of hind limbs via functional tests (sit-to-move and lie-to-move), movement in stairs, evaluation of hind limb muscle atrophy, manual evaluation of hind limb static weight bearing, quantitative measurement of static weight bearing of hind limbs with bathroom scales, and passive range of motion of hind limb stifle (flexion and extension) and tarsal (flexion and extension) joints using a universal goniometer. The results were compared with those from an orthopaedic examination, force plate analysis, radiographic evaluation, and a conclusive assessment. Congruity of the methods was assessed with a combination of three statistical approaches (Fisher’s exact test and two differently calculated proportions of agreeing observations), and the components were ranked from best to worst. Sensitivities of all of the physiotherapeutic evaluation methods against each standard were calculated. Results Evaluation of asymmetry in a sitting and lying position, assessment of muscle atrophy, manual and measured static weight bearing, and measurement of stifle passive range of motion were the most valid and sensitive physiotherapeutic evaluation methods. Conclusions Ranking of the various physiotherapeutic evaluation methods was accomplished. Several of these methods can be considered valid and sensitive when examining the functionality of dogs with stifle problems. PMID:23566355

Comparative assessment of three standardized robotic surgery training methods.

PubMed

Hung, Andrew J; Jayaratna, Isuru S; Teruya, Kara; Desai, Mihir M; Gill, Inderbir S; Goh, Alvin C

2013-10-01

To evaluate three standardized robotic surgery training methods, inanimate, virtual reality and in vivo, for their construct validity. To explore the concept of cross-method validity, where the relative performance of each method is compared. Robotic surgical skills were prospectively assessed in 49 participating surgeons who were classified as follows: 'novice/trainee': urology residents, previous experience <30 cases (n = 38) and 'experts': faculty surgeons, previous experience ≥30 cases (n = 11). Three standardized, validated training methods were used: (i) structured inanimate tasks; (ii) virtual reality exercises on the da Vinci Skills Simulator (Intuitive Surgical, Sunnyvale, CA, USA); and (iii) a standardized robotic surgical task in a live porcine model with performance graded by the Global Evaluative Assessment of Robotic Skills (GEARS) tool. A Kruskal-Wallis test was used to evaluate performance differences between novices and experts (construct validity). Spearman's correlation coefficient (ρ) was used to measure the association of performance across inanimate, simulation and in vivo methods (cross-method validity). Novice and expert surgeons had previously performed a median (range) of 0 (0-20) and 300 (30-2000) robotic cases, respectively (P < 0.001). Construct validity: experts consistently outperformed residents with all three methods (P < 0.001). Cross-method validity: overall performance of inanimate tasks significantly correlated with virtual reality robotic performance (ρ = -0.7, P < 0.001) and in vivo robotic performance based on GEARS (ρ = -0.8, P < 0.0001). Virtual reality performance and in vivo tissue performance were also found to be strongly correlated (ρ = 0.6, P < 0.001). We propose the novel concept of cross-method validity, which may provide a method of evaluating the relative value of various forms of skills education and assessment. We externally confirmed the construct validity of each featured training tool. © 2013 BJU International.

Validity and Reliability of the 8-Item Work Limitations Questionnaire.

PubMed

Walker, Timothy J; Tullar, Jessica M; Diamond, Pamela M; Kohl, Harold W; Amick, Benjamin C

2017-12-01

Purpose To evaluate factorial validity, scale reliability, test-retest reliability, convergent validity, and discriminant validity of the 8-item Work Limitations Questionnaire (WLQ) among employees from a public university system. Methods A secondary analysis using de-identified data from employees who completed an annual Health Assessment between the years 2009-2015 tested research aims. Confirmatory factor analysis (CFA) (n = 10,165) tested the latent structure of the 8-item WLQ. Scale reliability was determined using a CFA-based approach while test-retest reliability was determined using the intraclass correlation coefficient. Convergent/discriminant validity was tested by evaluating relations between the 8-item WLQ with health/performance variables for convergent validity (health-related work performance, number of chronic conditions, and general health) and demographic variables for discriminant validity (gender and institution type). Results A 1-factor model with three correlated residuals demonstrated excellent model fit (CFI = 0.99, TLI = 0.99, RMSEA = 0.03, and SRMR = 0.01). The scale reliability was acceptable (0.69, 95% CI 0.68-0.70) and the test-retest reliability was very good (ICC = 0.78). Low-to-moderate associations were observed between the 8-item WLQ and the health/performance variables while weak associations were observed between the demographic variables. Conclusions The 8-item WLQ demonstrated sufficient reliability and validity among employees from a public university system. Results suggest the 8-item WLQ is a usable alternative for studies when the more comprehensive 25-item WLQ is not available.

Validation of microbiological testing in cardiovascular tissue banks: results of a quality round trial.

PubMed

de By, Theo M M H; McDonald, Carl; Süßner, Susanne; Davies, Jill; Heng, Wee Ling; Jashari, Ramadan; Bogers, Ad J J C; Petit, Pieter

2017-11-01

Surgeons needing human cardiovascular tissue for implantation in their patients are confronted with cardiovascular tissue banks that use different methods to identify and decontaminate micro-organisms. To elucidate these differences, we compared the quality of processing methods in 20 tissue banks and 1 reference laboratory. We did this to validate the results for accepting or rejecting tissue. We included the decontamination methods used and the influence of antibiotic cocktails and residues with results and controls. The minor details of the processes were not included. To compare the outcomes of microbiological testing and decontamination methods of heart valve allografts in cardiovascular tissue banks, an international quality round was organized. Twenty cardiovascular tissue banks participated in this quality round. The quality round method was validated first and consisted of sending purposely contaminated human heart valve tissue samples with known micro-organisms to the participants. The participants identified the micro-organisms using their local decontamination methods. Seventeen of the 20 participants correctly identified the micro-organisms; if these samples were heart valves to be released for implantation, 3 of the 20 participants would have decided to accept their result for release. Decontamination was shown not to be effective in 13 tissue banks because of growth of the organisms after decontamination. Articles in the literature revealed that antibiotics are effective at 36°C and not, or less so, at 2-8°C. The decontamination procedure, if it is validated, will ensure that the tissue contains no known micro-organisms. This study demonstrates that the quality round method of sending contaminated tissues and assessing the results of the microbiological cultures is an effective way of validating the processes of tissue banks. Only when harmonization, based on validated methods, has been achieved, will surgeons be able to fully rely on the methods used and have confidence in the consistent sterility of the tissue grafts. Tissue banks should validate their methods so that all stakeholders can trust the outcomes. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Errors in reporting on dissolution research: methodological and statistical implications.

PubMed

Jasińska-Stroschein, Magdalena; Kurczewska, Urszula; Orszulak-Michalak, Daria

2017-02-01

In vitro dissolution testing provides useful information at clinical and preclinical stages of the drug development process. The study includes pharmaceutical papers on dissolution research published in Polish journals between 2010 and 2015. They were analyzed with regard to information provided by authors about chosen methods, performed validation, statistical reporting or assumptions used to properly compare release profiles considering the present guideline documents addressed to dissolution methodology and its validation. Of all the papers included in the study, 23.86% presented at least one set of validation parameters, 63.64% gave the results of the weight uniformity test, 55.68% content determination, 97.73% dissolution testing conditions, and 50% discussed a comparison of release profiles. The assumptions for methods used to compare dissolution profiles were discussed in 6.82% of papers. By means of example analyses, we demonstrate that the outcome can be influenced by the violation of several assumptions or selection of an improper method to compare dissolution profiles. A clearer description of the procedures would undoubtedly increase the quality of papers in this area.

Validation of Methods to Predict Vibration of a Panel in the Near Field of a Hot Supersonic Rocket Plume

NASA Technical Reports Server (NTRS)

Bremner, P. G.; Blelloch, P. A.; Hutchings, A.; Shah, P.; Streett, C. L.; Larsen, C. E.

2011-01-01

This paper describes the measurement and analysis of surface fluctuating pressure level (FPL) data and vibration data from a plume impingement aero-acoustic and vibration (PIAAV) test to validate NASA s physics-based modeling methods for prediction of panel vibration in the near field of a hot supersonic rocket plume. For this test - reported more fully in a companion paper by Osterholt & Knox at 26th Aerospace Testing Seminar, 2011 - the flexible panel was located 2.4 nozzle diameters from the plume centerline and 4.3 nozzle diameters downstream from the nozzle exit. The FPL loading is analyzed in terms of its auto spectrum, its cross spectrum, its spatial correlation parameters and its statistical properties. The panel vibration data is used to estimate the in-situ damping under plume FPL loading conditions and to validate both finite element analysis (FEA) and statistical energy analysis (SEA) methods for prediction of panel response. An assessment is also made of the effects of non-linearity in the panel elasticity.

Construct Validity of Physical Fitness Tests

DTIC Science & Technology

2011-02-03

Medicine and Science in Sports and Exercise , 21, 319-324. *Fleishman, E. A. (1964). The structure and measurement of physical fitness. Englewood Cliffs...Quarterly for Exercise and Sport, 64, 256-273. *McCloy, E. (1935). Factor analysis methods in the measurement of physical abilities. Research Quarterly...Research Quarterly, 34, 525. Physical Fitness Test Validity 23 Powers, S. K., & Howley, E. T. (1990). Exercise physiology: Theory and application to

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhinefrank, Kenneth E.; Lenee-Bluhm, Pukha; Prudell, Joseph H.

The most prudent path to a full-scale design, build and deployment of a wave energy conversion (WEC) system involves establishment of validated numerical models using physical experiments in a methodical scaling program. This Project provides essential additional rounds of wave tank testing at 1:33 scale and ocean/bay testing at a 1:7 scale, necessary to validate numerical modeling that is essential to a utility-scale WEC design and associated certification.

Screening for Elder Abuse among Turkish Older People: Validity of the Hwalek-Sengstock Elder Abuse Screening Test (H-S "East")

ERIC Educational Resources Information Center

Özmete, Emine; Megahead, Hamido A.

2017-01-01

Objective: This study aims to adapt "The Hwalek-Sengstock Elder Abuse Screening Test (H-S "East")" (Neale, Hwalek, Scott, Sengstock, & Stahl, 1991) to Turkish and to assess its validity and reliability while determining the factors that affect elder abuse. Method: The sample of the study is composed of 465 elderly women and…

The NASA Hyper-X Program

NASA Technical Reports Server (NTRS)

Freeman, Delman C., Jr.; Reubush, Daivd E.; McClinton, Charles R.; Rausch, Vincent L.; Crawford, J. Larry

1997-01-01

This paper provides an overview of NASA's Hyper-X Program; a focused hypersonic technology effort designed to move hypersonic, airbreathing vehicle technology from the laboratory environment to the flight environment. This paper presents an overview of the flight test program, research objectives, approach, schedule and status. Substantial experimental database and concept validation have been completed. The program is currently concentrating on the first, Mach 7, vehicle development, verification and validation in preparation for wind-tunnel testing in 1998 and flight testing in 1999. Parallel to this effort the Mach 5 and 10 vehicle designs are being finalized. Detailed analytical and experimental evaluation of the Mach 7 vehicle at the flight conditions is nearing completion, and will provide a database for validation of design methods once flight test data are available.

NASA EEE Parts and Advanced Interconnect Program (AIP)

NASA Technical Reports Server (NTRS)

Gindorf, T.; Garrison, A.

1996-01-01

none given From Program Objectives: I. Accelerate the readiness of new technologies through development of validation, assessment and test method/tools II. Provide NASA Projects infusion paths for emerging technologies III. Provide NASA Projects technology selection, application and validation guidelines for harware and processes IV. Disseminate quality assurance, reliability, validation, tools and availability information to the NASA community.

Background information for the Leaching environmental Assessment Framework (LEAF) test methods

EPA Science Inventory

The U.S. Environmental Protection Agency Office of Resource Conservation and Recovery has initiated the review and validation process for four leaching tests under consideration for inclusion into SW-846: Method 1313 "Liquid-Solid Partitioning as a Function of Extract pH for Co...

Polish Adult Reading Test (PART) - construction of Polish test for estimating the level of premorbid intelligence in schizophrenia.

PubMed

Karakuła-Juchnowicz, Hanna; Stecka, Mariola

2017-08-29

In view of unavailability in Poland of the standardized methods to measure PIQ, the aim of the work was to develop a Polish test to assess the premorbid level of intelligence - PART(Polish AdultReading Test) and to measureits psychometric properties, such as validity, reliability as well as standardization in the group of schizophrenia patients. The principles of PART construction were based on the idea of popular worldwide National Adult Reading Test by Hazel Nelson. The research comprised a group of 122 subjects (65 schizophrenia patients and 57 healthy people), aged 18-60 years, matched for age and gender. PART appears to be a method with high internal consistency and reliability measured by test-retest, inter-rater reliability, and the method with acceptable diagnostic and prognostic validity. The standardized procedures of PART have been investigated and described. Considering the psychometric values of PART and a short time of its performance, the test may be a useful diagnostic instrument in the assessment of premorbid level of intelligence in a group of schizophrenic patients.

A Method of Q-Matrix Validation for the Linear Logistic Test Model

PubMed Central

Baghaei, Purya; Hohensinn, Christine

2017-01-01

The linear logistic test model (LLTM) is a well-recognized psychometric model for examining the components of difficulty in cognitive tests and validating construct theories. The plausibility of the construct model, summarized in a matrix of weights, known as the Q-matrix or weight matrix, is tested by (1) comparing the fit of LLTM with the fit of the Rasch model (RM) using the likelihood ratio (LR) test and (2) by examining the correlation between the Rasch model item parameters and LLTM reconstructed item parameters. The problem with the LR test is that it is almost always significant and, consequently, LLTM is rejected. The drawback of examining the correlation coefficient is that there is no cut-off value or lower bound for the magnitude of the correlation coefficient. In this article we suggest a simulation method to set a minimum benchmark for the correlation between item parameters from the Rasch model and those reconstructed by the LLTM. If the cognitive model is valid then the correlation coefficient between the RM-based item parameters and the LLTM-reconstructed item parameters derived from the theoretical weight matrix should be greater than those derived from the simulated matrices. PMID:28611721

A critical analysis of test-retest reliability in instrument validation studies of cancer patients under palliative care: a systematic review

PubMed Central

2014-01-01

Background Patient-reported outcome validation needs to achieve validity and reliability standards. Among reliability analysis parameters, test-retest reliability is an important psychometric property. Retested patients must be in a clinically stable condition. This is particularly problematic in palliative care (PC) settings because advanced cancer patients are prone to a faster rate of clinical deterioration. The aim of this study was to evaluate the methods by which multi-symptom and health-related qualities of life (HRQoL) based on patient-reported outcomes (PROs) have been validated in oncological PC settings with regards to test-retest reliability. Methods A systematic search of PubMed (1966 to June 2013), EMBASE (1980 to June 2013), PsychInfo (1806 to June 2013), CINAHL (1980 to June 2013), and SCIELO (1998 to June 2013), and specific PRO databases was performed. Studies were included if they described a set of validation studies. Studies were included if they described a set of validation studies for an instrument developed to measure multi-symptom or multidimensional HRQoL in advanced cancer patients under PC. The COSMIN checklist was used to rate the methodological quality of the study designs. Results We identified 89 validation studies from 746 potentially relevant articles. From those 89 articles, 31 measured test-retest reliability and were included in this review. Upon critical analysis of the overall quality of the criteria used to determine the test-retest reliability, 6 (19.4%), 17 (54.8%), and 8 (25.8%) of these articles were rated as good, fair, or poor, respectively, and no article was classified as excellent. Multi-symptom instruments were retested over a shortened interval when compared to the HRQoL instruments (median values 24 hours and 168 hours, respectively; p = 0.001). Validation studies that included objective confirmation of clinical stability in their design yielded better results for the test-retest analysis with regard to both pain and global HRQoL scores (p < 0.05). The quality of the statistical analysis and its description were of great concern. Conclusion Test-retest reliability has been infrequently and poorly evaluated. The confirmation of clinical stability was an important factor in our analysis, and we suggest that special attention be focused on clinical stability when designing a PRO validation study that includes advanced cancer patients under PC. PMID:24447633

Validity and test-retest reliability in assessing current body size with figure drawings in Chinese adolescents.

PubMed

Lo, Wing-Sze; Ho, Sai-Yin; Wong, Bonny Yee-Man; Mak, Kwok-Kei; Lam, Tai-Hing

2011-06-01

The reliability and validity of Stunkard's Figure Rating Scale (FRS) as a measure of current body size (CBS) was established in Western adolescent girls but not in non-Western population. We examined the validity and test-retest reliability of Stunkard's FRS in assessing CBS among Chinese adolescents. Methods. In a school-based survey in Hong Kong, 5666 adolescents (boys: 45.1%; mean age 14.7 years) provided data on self-reported height and weight, CBS, perceived weight status, and health-related quality of life using the Medical Outcomes Study Short-Form version 2 (SF-12v2). Height and weight were also objectively measured. Spearman's correlation was used to assess construct validity, concurrent validity and test-retest reliability. Convergent and discriminant validity were good: CBS correlated strongly with weight and self-reported/measured BMI, but only weakly with SF-12v2. CBS correlated strongly with perceived weight status, showing concurrent validity. Spearman's correlation (r) for CBS was 0.78 for girls and 0.72 for boys indicating good test-retest reliability. Validity and reliability results did not differ significantly between senior and junior grade adolescents. Our findings support the use of Stunkard's FRS to measure body size among Chinese adolescents.

[Turkish validity and reliability study of fear of pain questionnaire-III].

PubMed

Ünver, Seher; Turan, Fatma Nesrin

2018-01-01

This study aimed to develop a Turkish version of the Fear of Pain Questionnaire-III developed by McNeil and Rainwater (1998) and examine its validity and reliability indicators. The study was conducted with 459 university students studying in the nursing department. The Turkish translation of the scale was conducted by language experts and the original scale owner. Expert opinions were taken for language validity, and the Lawshe's content validity ratio formula was used to calculate the content validity. Exploratory factor analysis was used to assess the construct validity. The factors were rotated using the Varimax rotation (orthogonal) method. For reliability indicators of the questionnaire, the internal consistency coefficient and test re-test reliability were utilized. Explanatory factor analyses using the three-factor model (explaining 50.5% of the total variance) revealed that the item factor loads varied were above the limit value of 0.30 which indicated that the questionnaire had good construct validity. The Cronbach's alpha value for the total questionnaire was 0.938, and test re-test value was 0.846 for the total scale. The Turkish version of the Fear of Pain Questionnaire-III had sufficiently high reliability and validity to be used as a tool in evaluating the fear of pain among the young Turkish population.

Subscale Validation of the Subsurface Active Filtration of Exhaust (SAFE) Approach to the NTP Ground Testing

NASA Technical Reports Server (NTRS)

Marshall, William M.; Borowski, Stanley K.; Bulman, Mel; Joyner, Russell; Martin, Charles R.

2015-01-01

Nuclear thermal propulsion (NTP) has been recognized as an enabling technology for missions to Mars and beyond. However, one of the key challenges of developing a nuclear thermal rocket is conducting verification and development tests on the ground. A number of ground test options are presented, with the Sub-surface Active Filtration of Exhaust (SAFE) method identified as a preferred path forward for the NTP program. The SAFE concept utilizes the natural soil characteristics present at the Nevada National Security Site to provide a natural filter for nuclear rocket exhaust during ground testing. A validation method of the SAFE concept is presented, utilizing a non-nuclear sub-scale hydrogen/oxygen rocket seeded with detectible radioisotopes. Additionally, some alternative ground test concepts, based upon the SAFE concept, are presented. Finally, an overview of the ongoing discussions of developing a ground test campaign are presented.

Validity and reliability of Patient-Reported Outcomes Measurement Information System (PROMIS) Instruments in Osteoarthritis

PubMed Central

Broderick, Joan E.; Schneider, Stefan; Junghaenel, Doerte U.; Schwartz, Joseph E.; Stone, Arthur A.

2013-01-01

Objective Evaluation of known group validity, ecological validity, and test-retest reliability of four domain instruments from the Patient Reported Outcomes Measurement System (PROMIS) in osteoarthritis (OA) patients. Methods Recruitment of an osteoarthritis sample and a comparison general population (GP) through an Internet survey panel. Pain intensity, pain interference, physical functioning, and fatigue were assessed for 4 consecutive weeks with PROMIS short forms on a daily basis and compared with same-domain Computer Adaptive Test (CAT) instruments that use a 7-day recall. Known group validity (comparison of OA and GP), ecological validity (comparison of aggregated daily measures with CATs), and test-retest reliability were evaluated. Results The recruited samples matched (age, sex, race, ethnicity) the demographic characteristics of the U.S. sample for arthritis and the 2009 Census for the GP. Compliance with repeated measurements was excellent: > 95%. Known group validity for CATs was demonstrated with large effect sizes (pain intensity: 1.42, pain interference: 1.25, and fatigue: .85). Ecological validity was also established through high correlations between aggregated daily measures and weekly CATs (≥ .86). Test-retest validity (7-day) was very good (≥ .80). Conclusion PROMIS CAT instruments demonstrated known group and ecological validity in a comparison of osteoarthritis patients with a general population sample. Adequate test-retest reliability was also observed. These data provide encouraging initial data on the utility of these PROMIS instruments for clinical and research outcomes in osteoarthritis patients. PMID:23592494

Identifying model error in metabolic flux analysis - a generalized least squares approach.

PubMed

Sokolenko, Stanislav; Quattrociocchi, Marco; Aucoin, Marc G

2016-09-13

The estimation of intracellular flux through traditional metabolic flux analysis (MFA) using an overdetermined system of equations is a well established practice in metabolic engineering. Despite the continued evolution of the methodology since its introduction, there has been little focus on validation and identification of poor model fit outside of identifying "gross measurement error". The growing complexity of metabolic models, which are increasingly generated from genome-level data, has necessitated robust validation that can directly assess model fit. In this work, MFA calculation is framed as a generalized least squares (GLS) problem, highlighting the applicability of the common t-test for model validation. To differentiate between measurement and model error, we simulate ideal flux profiles directly from the model, perturb them with estimated measurement error, and compare their validation to real data. Application of this strategy to an established Chinese Hamster Ovary (CHO) cell model shows how fluxes validated by traditional means may be largely non-significant due to a lack of model fit. With further simulation, we explore how t-test significance relates to calculation error and show that fluxes found to be non-significant have 2-4 fold larger error (if measurement uncertainty is in the 5-10 % range). The proposed validation method goes beyond traditional detection of "gross measurement error" to identify lack of fit between model and data. Although the focus of this work is on t-test validation and traditional MFA, the presented framework is readily applicable to other regression analysis methods and MFA formulations.

Standardization, evaluation and early-phase method validation of an analytical scheme for batch-consistency N-glycosylation analysis of recombinant produced glycoproteins.

PubMed

Zietze, Stefan; Müller, Rainer H; Brecht, René

2008-03-01

In order to set up a batch-to-batch-consistency analytical scheme for N-glycosylation analysis, several sample preparation steps including enzyme digestions and fluorophore labelling and two HPLC-methods were established. The whole method scheme was standardized, evaluated and validated according to the requirements on analytical testing in early clinical drug development by usage of a recombinant produced reference glycoprotein (RGP). The standardization of the methods was performed by clearly defined standard operation procedures. During evaluation of the methods, the major interest was in the loss determination of oligosaccharides within the analytical scheme. Validation of the methods was performed with respect to specificity, linearity, repeatability, LOD and LOQ. Due to the fact that reference N-glycan standards were not available, a statistical approach was chosen to derive accuracy from the linearity data. After finishing the validation procedure, defined limits for method variability could be calculated and differences observed in consistency analysis could be separated into significant and incidental ones.

The composite dynamic method as evidence for age-specific waterfowl mortality

USGS Publications Warehouse

Burnham, Kenneth P.; Anderson, David R.

1979-01-01

For the past 25 years estimation of mortality rates for waterfowl has been based almost entirely on the composite dynamic life table. We examined the specific assumptions for this method and derived a valid goodness of fit test. We performed this test on 45 data sets representing a cross section of banded sampled for various waterfowl species, geographic areas, banding periods, and age/sex classes. We found that: (1) the composite dynamic method was rejected (P <0.001) in 37 of the 45 data sets (in fact, 29 were rejected at P <0.00001) and (2) recovery and harvest rates are year-specific (a critical violation of the necessary assumptions). We conclude that the restrictive assumptions required for the composite dynamic method to produce valid estimates of mortality rates are not met in waterfowl data. Also we demonstrate that even when the required assumptions are met, the method produces very biased estimates of age-specific mortality rates. We believe the composite dynamic method should not be used in the analysis of waterfowl banding data. Furthermore, the composite dynamic method does not provide valid evidence for age-specific mortality rates in waterfowl.

Validation conform ISO-15189 of assays in the field of autoimmunity: Joint efforts in The Netherlands.

PubMed

Mulder, Leontine; van der Molen, Renate; Koelman, Carin; van Leeuwen, Ester; Roos, Anja; Damoiseaux, Jan

2018-05-01

ISO 15189:2012 requires validation of methods used in the medical laboratory, and lists a series of performance parameters for consideration to include. Although these performance parameters are feasible for clinical chemistry analytes, application in the validation of autoimmunity tests is a challenge. Lack of gold standards or reference methods in combination with the scarcity of well-defined diagnostic samples of patients with rare diseases make validation of new assays difficult. The present manuscript describes the initiative of Dutch medical immunology laboratory specialists to combine efforts and perform multi-center validation studies of new assays in the field of autoimmunity. Validation data and reports are made available to interested Dutch laboratory specialists. Copyright © 2018 Elsevier B.V. All rights reserved.

Bias correction for selecting the minimal-error classifier from many machine learning models.

PubMed

Ding, Ying; Tang, Shaowu; Liao, Serena G; Jia, Jia; Oesterreich, Steffi; Lin, Yan; Tseng, George C

2014-11-15

Supervised machine learning is commonly applied in genomic research to construct a classifier from the training data that is generalizable to predict independent testing data. When test datasets are not available, cross-validation is commonly used to estimate the error rate. Many machine learning methods are available, and it is well known that no universally best method exists in general. It has been a common practice to apply many machine learning methods and report the method that produces the smallest cross-validation error rate. Theoretically, such a procedure produces a selection bias. Consequently, many clinical studies with moderate sample sizes (e.g. n = 30-60) risk reporting a falsely small cross-validation error rate that could not be validated later in independent cohorts. In this article, we illustrated the probabilistic framework of the problem and explored the statistical and asymptotic properties. We proposed a new bias correction method based on learning curve fitting by inverse power law (IPL) and compared it with three existing methods: nested cross-validation, weighted mean correction and Tibshirani-Tibshirani procedure. All methods were compared in simulation datasets, five moderate size real datasets and two large breast cancer datasets. The result showed that IPL outperforms the other methods in bias correction with smaller variance, and it has an additional advantage to extrapolate error estimates for larger sample sizes, a practical feature to recommend whether more samples should be recruited to improve the classifier and accuracy. An R package 'MLbias' and all source files are publicly available. tsenglab.biostat.pitt.edu/software.htm. ctseng@pitt.edu Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Resolution of Forces and Strain Measurements from an Acoustic Ground Test

NASA Technical Reports Server (NTRS)

Smith, Andrew M.; LaVerde, Bruce T.; Hunt, Ronald; Waldon, James M.

2013-01-01

The Conservatism in Typical Vibration Tests was Demonstrated: Vibration test at component level produced conservative force reactions by approximately a factor of 4 (approx.12 dB) as compared to the integrated acoustic test in 2 out of 3 axes. Reaction Forces Estimated at the Base of Equipment Using a Finite Element Based Method were Validated: FEM based estimate of interface forces may be adequate to guide development of vibration test criteria with less conservatism. Element Forces Estimated in Secondary Structure Struts were Validated: Finite element approach provided best estimate of axial strut forces in frequency range below 200 Hz where a rigid lumped mass assumption for the entire electronics box was valid. Models with enough fidelity to represent diminishing apparent mass of equipment are better suited for estimating force reactions across the frequency range. Forward Work: Demonstrate the reduction in conservatism provided by; Current force limited approach and an FEM guided approach. Validate proposed CMS approach to estimate coupled response from uncoupled system characteristics for vibroacoustics.

Feasibility study on inverse four-dimensional dose reconstruction using the continuous dose-image of EPID

PubMed Central

Yeo, Inhwan Jason; Jung, Jae Won; Yi, Byong Yong; Kim, Jong Oh

2013-01-01

Purpose: When an intensity-modulated radiation beam is delivered to a moving target, the interplay effect between dynamic beam delivery and the target motion due to miss-synchronization can cause unpredictable dose delivery. The portal dose image in electronic portal imaging device (EPID) represents radiation attenuated and scattered through target media. Thus, it may possess information about delivered radiation to the target. Using a continuous scan (cine) mode of EPID, which provides temporal dose images related to target and beam movements, the authors’ goal is to perform four-dimensional (4D) dose reconstruction. Methods: To evaluate this hypothesis, first, the authors have derived and subsequently validated a fast method of dose reconstruction based on virtual beamlet calculations of dose responses using a test intensity-modulated beam. This method was necessary for processing a large number of EPID images pertinent for four-dimensional reconstruction. Second, cine mode acquisition after summation over all images was validated through comparison with integration mode acquisition on EPID (IAS3 and aS1000) for the test beam. This was to confirm the agreement of the cine mode with the integrated mode, specifically for the test beam, which is an accepted mode of image acquisition for dosimetry with EPID. Third, in-phantom film and exit EPID dosimetry was performed on a moving platform using the same beam. Heterogeneous as well as homogeneous phantoms were used. The cine images were temporally sorted at 10% interval. The authors have performed dose reconstruction to the in-phantom plane from the sorted cine images using the above validated method of dose reconstruction. The reconstructed dose from each cine image was summed to compose a total reconstructed dose from the test beam delivery, and was compared with film measurements. Results: The new method of dose reconstruction was validated showing greater than 95.3% pass rates of the gamma test with the criteria of dose difference of 3% and distance to agreement of 3 mm. The dose comparison of the reconstructed dose with the measured dose for the two phantoms showed pass rates higher than 96.4% given the same criteria. Conclusions: Feasibility of 4D dose reconstruction was successfully demonstrated in this study. The 4D dose reconstruction demonstrated in this study can be a promising dose validation method for radiation delivery on moving organs. PMID:23635250

Validity and Reliability of Published Comprehensive Theory of Mind Tests for Normal Preschool Children: A Systematic Review

PubMed Central

Ziatabar Ahmadi, Seyyede Zohreh; Jalaie, Shohreh; Ashayeri, Hassan

2015-01-01

Objective: Theory of mind (ToM) or mindreading is an aspect of social cognition that evaluates mental states and beliefs of oneself and others. Validity and reliability are very important criteria when evaluating standard tests; and without them, these tests are not usable. The aim of this study was to systematically review the validity and reliability of published English comprehensive ToM tests developed for normal preschool children. Method: We searched MEDLINE (PubMed interface), Web of Science, Science direct, PsycINFO, and also evidence base Medicine (The Cochrane Library) databases from 1990 to June 2015. Search strategy was Latin transcription of ‘Theory of Mind’ AND test AND children. Also, we manually studied the reference lists of all final searched articles and carried out a search of their references. Inclusion criteria were as follows: Valid and reliable diagnostic ToM tests published from 1990 to June 2015 for normal preschool children; and exclusion criteria were as follows: the studies that only used ToM tests and single tasks (false belief tasks) for ToM assessment and/or had no description about structure, validity or reliability of their tests. Methodological quality of the selected articles was assessed using the Critical Appraisal Skills Programme (CASP). Result: In primary searching, we found 1237 articles in total databases. After removing duplicates and applying all inclusion and exclusion criteria, we selected 11 tests for this systematic review. Conclusion: There were a few valid, reliable and comprehensive ToM tests for normal preschool children. However, we had limitations concerning the included articles. The defined ToM tests were different in populations, tasks, mode of presentations, scoring, mode of responses, times and other variables. Also, they had various validities and reliabilities. Therefore, it is recommended that the researchers and clinicians select the ToM tests according to their psychometric characteristics, validity and reliability. PMID:27006666

Paediatric Automatic Phonological Analysis Tools (APAT).

PubMed

Saraiva, Daniela; Lousada, Marisa; Hall, Andreia; Jesus, Luis M T

2017-12-01

To develop the pediatric Automatic Phonological Analysis Tools (APAT) and to estimate inter and intrajudge reliability, content validity, and concurrent validity. The APAT were constructed using Excel spreadsheets with formulas. The tools were presented to an expert panel for content validation. The corpus used in the Portuguese standardized test Teste Fonético-Fonológico - ALPE produced by 24 children with phonological delay or phonological disorder was recorded, transcribed, and then inserted into the APAT. Reliability and validity of APAT were analyzed. The APAT present strong inter- and intrajudge reliability (>97%). The content validity was also analyzed (ICC = 0.71), and concurrent validity revealed strong correlations between computerized and manual (traditional) methods. The development of these tools contributes to fill existing gaps in clinical practice and research, since previously there were no valid and reliable tools/instruments for automatic phonological analysis, which allowed the analysis of different corpora.

Testing the convergent validity of the contingent valuation and travel cost methods in valuing the benefits of health care.

PubMed

Clarke, Philip M

2002-03-01

In this study, the convergent validity of the contingent valuation method (CVM) and travel cost method (TCM) is tested by comparing estimates of the willingness to pay (WTP) for improving access to mammographic screening in rural areas of Australia. It is based on a telephone survey of 458 women in 19 towns, in which they were asked about their recent screening behaviour and their WTP to have a mobile screening unit visit their nearest town. After eliminating missing data and other non-usable responses the contingent valuation experiment and travel cost model were based on information from 372 and 319 women, respectively. Estimates of the maximum WTP for the use of mobile screening units were derived using both methods and compared. The highest mean WTP estimated using the TCM was $83.10 (95% C.I. $99.06-$68.53), which is significantly less than the estimate of $148.09 ($131.13-$166.60) using the CVM. This could be due to the CVM estimates also reflecting non-use values such as altruism, or a range of potential biases that are known to affect both methods. Further tests of validity are required in order to gain a greater understanding of the relationship between these two methods of estimating WTP. Copyright 2001 John Wiley & Sons, Ltd.

Validation of a Five Plate Test, the STAR protocol, for the screening of antibiotic residues in muscle from different animal species according to European Decision 2002/657/EC.

PubMed

Gaudin, V; Hedou, C; Rault, A; Verdon, E

2010-07-01

The STAR protocol is a Five Plate Test (FPT) developed several years ago at the Community Reference Laboratory (CRL) for the screening of antimicrobial residues in milk and muscle. This paper presents the validation of this method according to European Decision 2002/657/EC and to an internal guideline for validation. A validation protocol based on 'simulated tissues' and on a list of 16 representative antimicrobials to be validated was implemented in our laboratory during several months for the STAR protocol. The performance characteristics of the method were determined (specificity, detection capabilities CCbeta, applicability, ruggedness). In conclusion, the STAR protocol is applicable to the broad-spectrum detection of antibiotic residues in muscles of different animal species (pig, cattle, sheep, poultry). The method has good specificity (false-positive rate = 4%). The detection capabilities were determined for 16 antibiotics from different families in relation to their respective maximum residue limit (MRL): beta-lactams (penicillins and cephalosporins < or = MRL), tetracyclines (< or = MRL and < or = 2.5 MRL), macrolides (2 MRL), quinolones (< or = 2 MRL), some sulphonamides (< or = 3 MRL), and trimethoprim (2 MRL). However, the sensitivity of the STAR protocol towards aminoglycosides (> 8 MRL) and florfenicol (< or = 10 MRL) was unsatisfactory (>MRL). The two objectives of this study were met: firstly, to validate the STAR protocol according to European Decision 2002/657/EC, then to demonstrate that the validation guideline developed to implement this decision is applicable to microbiological plate tests even for muscle. The use of simulated tissue appeared a good compromise between spiked discs with antibiotic solutions and incurred tissues. In addition, the choice of a list of representative antibiotics allowed the reduction of the scope of the validation, which was already costly in time and effort.

Development and validation of a Daphnia magna four-day survival and growth test method

EPA Science Inventory

Zooplankton are an important part of the aquatic ecology of all lakes and streams. As a result, numerous methods have been developed to assess the quality of waterbodies using various zooplankton species. Included in these is the freshwater species Daphnia magna. Current test me...

Experimental Validation of the Dynamic Inertia Measurement Method to Find the Mass Properties of an Iron Bird Test Article

NASA Technical Reports Server (NTRS)

Chin, Alexander; Herrera, Claudia; Spivey, Natalie; Fladung, William; Cloutier, David

2015-01-01

This presentation describes the DIM method and how it measures the inertia properties of an object by analyzing the frequency response functions measured during a ground vibration test (GVT). The DIM method has been in development at the University of Cincinnati and has shown success on a variety of small scale test articles. The NASA AFRC version was modified for larger applications.

Validation of asthma recording in electronic health records: a systematic review

PubMed Central

Nissen, Francis; Quint, Jennifer K; Wilkinson, Samantha; Mullerova, Hana; Smeeth, Liam; Douglas, Ian J

2017-01-01

Objective To describe the methods used to validate asthma diagnoses in electronic health records and summarize the results of the validation studies. Background Electronic health records are increasingly being used for research on asthma to inform health services and health policy. Validation of the recording of asthma diagnoses in electronic health records is essential to use these databases for credible epidemiological asthma research. Methods We searched EMBASE and MEDLINE databases for studies that validated asthma diagnoses detected in electronic health records up to October 2016. Two reviewers independently assessed the full text against the predetermined inclusion criteria. Key data including author, year, data source, case definitions, reference standard, and validation statistics (including sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) were summarized in two tables. Results Thirteen studies met the inclusion criteria. Most studies demonstrated a high validity using at least one case definition (PPV >80%). Ten studies used a manual validation as the reference standard; each had at least one case definition with a PPV of at least 63%, up to 100%. We also found two studies using a second independent database to validate asthma diagnoses. The PPVs of the best performing case definitions ranged from 46% to 58%. We found one study which used a questionnaire as the reference standard to validate a database case definition; the PPV of the case definition algorithm in this study was 89%. Conclusion Attaining high PPVs (>80%) is possible using each of the discussed validation methods. Identifying asthma cases in electronic health records is possible with high sensitivity, specificity or PPV, by combining multiple data sources, or by focusing on specific test measures. Studies testing a range of case definitions show wide variation in the validity of each definition, suggesting this may be important for obtaining asthma definitions with optimal validity. PMID:29238227

A Method and a Model for Describing Competence and Adjustment: A Preschool Version of the Classroom Behavior Inventory.

ERIC Educational Resources Information Center

Schaefer, Earl S.; Edgerton, Marianna D.

A preschool version of the Classroom Behavior Inventory which provides a method for collecting valid data on a child's classroom behavior from day care and preschool teachers, was developed to complement the earlier form which was developed and validated for elementary school populations. The new version was tested with a pilot group of twenty-two…

A novel method to remotely measure food intake of free-living individuals in real time: the remote food photography method.

PubMed

Martin, Corby K; Han, Hongmei; Coulon, Sandra M; Allen, H Raymond; Champagne, Catherine M; Anton, Stephen D

2009-02-01

The aim of the present study was to report the first reliability and validity tests of the remote food photography method (RFPM), which consists of camera-enabled cell phones with data transfer capability. Participants take and transmit photographs of food selection and plate waste to researchers/clinicians for analysis. Following two pilot studies, adult participants (n 52; BMI 20-35 kg/m2 inclusive) were randomly assigned to the dine-in or take-out group. Energy intake (EI) was measured for 3 d. The dine-in group ate lunch and dinner in the laboratory. The take-out group ate lunch in the laboratory and dinner in free-living conditions (participants received a cooler with pre-weighed food that they returned the following morning). EI was measured with the RFPM and by directly weighing foods. The RFPM was tested in laboratory and free-living conditions. Reliability was tested over 3 d and validity was tested by comparing directly weighed EI to EI estimated with the RFPM using Bland-Altman analysis. The RFPM produced reliable EI estimates over 3 d in laboratory (r 0.62; P < 0.0001) and free-living (r 0.68; P < 0.0001) conditions. Weighed EI correlated highly with EI estimated with the RFPM in laboratory and free-living conditions (r>0.93; P < 0.0001). In two laboratory-based validity tests, the RFPM underestimated EI by - 4.7 % (P = 0.046) and - 5.5 % (P = 0.076). In free-living conditions, the RFPM underestimated EI by - 6.6 % (P = 0.017). Bias did not differ by body weight or age. The RFPM is a promising new method for accurately measuring the EI of free-living individuals. Error associated with the method is small compared with self-report methods.

Scoring Method of a Situational Judgment Test: Influence on Internal Consistency Reliability, Adverse Impact and Correlation with Personality?

ERIC Educational Resources Information Center

De Leng, W. E.; Stegers-Jager, K. M.; Husbands, A.; Dowell, J. S.; Born, M. Ph.; Themmen, A. P.

2017-01-01

Situational Judgment Tests (SJTs) are increasingly used for medical school selection. Scoring an SJT is more complicated than scoring a knowledge test, because there are no objectively correct answers. The scoring method of an SJT may influence the construct and concurrent validity and the adverse impact with respect to non-traditional students.…

Modernization of AOAC Nutrient Methods by Stakeholder Panel on Infant Formula and Adult Nutritionals.

PubMed

Sullivan, Darryl

2016-01-01

Infant formula is one of the most highly regulated products in the world. To comply with global regulations and to ensure the products are manufactured within product specifications, accurate analytical testing is required. Most of the AOAC INTERNATIONAL legacy test methods for infant formula were developed and validated in the 1980s and 1990s. Although these methods performed very well for many years, infant formulas have been updated, and today's products contain many new and novel ingredients. There were a number of cases in which the legacy AOAC methods began to result in problems with the analysis of modern infant formulas, and the use of these methods caused some disputes with regulatory agencies. In 2010, AOAC reached an agreement with the International Formula Council, which has changed its name to the Infant Nutrition Council of America, regarding a project to modernize these AOAC infant-formula test methods. This agreement led to the development of Standard Method Performance Requirements (SMPRs(®)) for 28 nutrients. After SMPR approval, methods were collected, evaluated, validated, and approved through the AOAC Official Methods(SM) process. Forty-seven methods have been approved as AOAC First Action Methods, and eight have been approved as Final Action.

Predicting implementation from organizational readiness for change: a study protocol

PubMed Central

2011-01-01

Background There is widespread interest in measuring organizational readiness to implement evidence-based practices in clinical care. However, there are a number of challenges to validating organizational measures, including inferential bias arising from the halo effect and method bias - two threats to validity that, while well-documented by organizational scholars, are often ignored in health services research. We describe a protocol to comprehensively assess the psychometric properties of a previously developed survey, the Organizational Readiness to Change Assessment. Objectives Our objective is to conduct a comprehensive assessment of the psychometric properties of the Organizational Readiness to Change Assessment incorporating methods specifically to address threats from halo effect and method bias. Methods and Design We will conduct three sets of analyses using longitudinal, secondary data from four partner projects, each testing interventions to improve the implementation of an evidence-based clinical practice. Partner projects field the Organizational Readiness to Change Assessment at baseline (n = 208 respondents; 53 facilities), and prospectively assesses the degree to which the evidence-based practice is implemented. We will conduct predictive and concurrent validities using hierarchical linear modeling and multivariate regression, respectively. For predictive validity, the outcome is the change from baseline to follow-up in the use of the evidence-based practice. We will use intra-class correlations derived from hierarchical linear models to assess inter-rater reliability. Two partner projects will also field measures of job satisfaction for convergent and discriminant validity analyses, and will field Organizational Readiness to Change Assessment measures at follow-up for concurrent validity (n = 158 respondents; 33 facilities). Convergent and discriminant validities will test associations between organizational readiness and different aspects of job satisfaction: satisfaction with leadership, which should be highly correlated with readiness, versus satisfaction with salary, which should be less correlated with readiness. Content validity will be assessed using an expert panel and modified Delphi technique. Discussion We propose a comprehensive protocol for validating a survey instrument for assessing organizational readiness to change that specifically addresses key threats of bias related to halo effect, method bias and questions of construct validity that often go unexplored in research using measures of organizational constructs. PMID:21777479

Procedures for Constructing and Using Criterion-Referenced Performance Tests.

ERIC Educational Resources Information Center

Campbell, Clifton P.; Allender, Bill R.

1988-01-01

Criterion-referenced performance tests (CRPT) provide a realistic method for objectively measuring task proficiency against predetermined attainment standards. This article explains the procedures of constructing, validating, and scoring CRPTs and includes a checklist for a welding test. (JOW)

State of the art on alternative methods to animal testing from an industrial point of view: ready for regulation?

PubMed

Ashton, Rachel; De Wever, Bart; Fuchs, Horst W; Gaca, Marianna; Hill, Erin; Krul, Cyrille; Poth, Albrecht; Roggen, Erwin L

2014-01-01

Despite changing attitudes towards animal testing and current legislation to protect experimental animals, the rate of animal experiments seems to have changed little in recent years. On May 15-16, 2013, the In Vitro Testing Industrial Platform (IVTIP) held an open meeting to discuss the state of the art in alternative methods, how companies have, can, and will need to adapt and what drives and hinders regulatory acceptance and use. Several key messages arose from the meeting. First, industry and regulatory bodies should not wait for complete suites of alternative tests to become available, but should begin working with methods available right now (e.g., mining of existing animal data to direct future studies, implementation of alternative tests wherever scientifically valid rather than continuing to rely on animal tests) in non-animal and animal integrated strategies to reduce the numbers of animals tested. Sharing of information (communication), harmonization and standardization (coordination), commitment and collaboration are all required to improve the quality and speed of validation, acceptance, and implementation of tests. Finally, we consider how alternative methods can be used in research and development before formal implementation in regulations. Here we present the conclusions on what can be done already and suggest some solutions and strategies for the future.

Validation of Clinical Testing for Warfarin Sensitivity

PubMed Central

Langley, Michael R.; Booker, Jessica K.; Evans, James P.; McLeod, Howard L.; Weck, Karen E.

2009-01-01

Responses to warfarin (Coumadin) anticoagulation therapy are affected by genetic variability in both the CYP2C9 and VKORC1 genes. Validation of pharmacogenetic testing for warfarin responses includes demonstration of analytical validity of testing platforms and of the clinical validity of testing. We compared four platforms for determining the relevant single nucleotide polymorphisms (SNPs) in both CYP2C9 and VKORC1 that are associated with warfarin sensitivity (Third Wave Invader Plus, ParagonDx/Cepheid Smart Cycler, Idaho Technology LightCycler, and AutoGenomics Infiniti). Each method was examined for accuracy, cost, and turnaround time. All genotyping methods demonstrated greater than 95% accuracy for identifying the relevant SNPs (CYP2C9 *2 and *3; VKORC1 −1639 or 1173). The ParagonDx and Idaho Technology assays had the shortest turnaround and hands-on times. The Third Wave assay was readily scalable to higher test volumes but had the longest hands-on time. The AutoGenomics assay interrogated the largest number of SNPs but had the longest turnaround time. Four published warfarin-dosing algorithms (Washington University, UCSF, Louisville, and Newcastle) were compared for accuracy for predicting warfarin dose in a retrospective analysis of a local patient population on long-term, stable warfarin therapy. The predicted doses from both the Washington University and UCSF algorithms demonstrated the best correlation with actual warfarin doses. PMID:19324988

Validation of clinical testing for warfarin sensitivity: comparison of CYP2C9-VKORC1 genotyping assays and warfarin-dosing algorithms.

PubMed

Langley, Michael R; Booker, Jessica K; Evans, James P; McLeod, Howard L; Weck, Karen E

2009-05-01

Responses to warfarin (Coumadin) anticoagulation therapy are affected by genetic variability in both the CYP2C9 and VKORC1 genes. Validation of pharmacogenetic testing for warfarin responses includes demonstration of analytical validity of testing platforms and of the clinical validity of testing. We compared four platforms for determining the relevant single nucleotide polymorphisms (SNPs) in both CYP2C9 and VKORC1 that are associated with warfarin sensitivity (Third Wave Invader Plus, ParagonDx/Cepheid Smart Cycler, Idaho Technology LightCycler, and AutoGenomics Infiniti). Each method was examined for accuracy, cost, and turnaround time. All genotyping methods demonstrated greater than 95% accuracy for identifying the relevant SNPs (CYP2C9 *2 and *3; VKORC1 -1639 or 1173). The ParagonDx and Idaho Technology assays had the shortest turnaround and hands-on times. The Third Wave assay was readily scalable to higher test volumes but had the longest hands-on time. The AutoGenomics assay interrogated the largest number of SNPs but had the longest turnaround time. Four published warfarin-dosing algorithms (Washington University, UCSF, Louisville, and Newcastle) were compared for accuracy for predicting warfarin dose in a retrospective analysis of a local patient population on long-term, stable warfarin therapy. The predicted doses from both the Washington University and UCSF algorithms demonstrated the best correlation with actual warfarin doses.

Testing survey-based methods for rapid monitoring of child mortality, with implications for summary birth history data.

PubMed

Brady, Eoghan; Hill, Kenneth

2017-01-01

Under-five mortality estimates are increasingly used in low and middle income countries to target interventions and measure performance against global development goals. Two new methods to rapidly estimate under-5 mortality based on Summary Birth Histories (SBH) were described in a previous paper and tested with data available. This analysis tests the methods using data appropriate to each method from 5 countries that lack vital registration systems. SBH data are collected across many countries through censuses and surveys, and indirect methods often rely upon their quality to estimate mortality rates. The Birth History Imputation method imputes data from a recent Full Birth History (FBH) onto the birth, death and age distribution of the SBH to produce estimates based on the resulting distribution of child mortality. DHS FBHs and MICS SBHs are used for all five countries. In the implementation, 43 of 70 estimates are within 20% of validation estimates (61%). Mean Absolute Relative Error is 17.7.%. 1 of 7 countries produces acceptable estimates. The Cohort Change method considers the differences in births and deaths between repeated Summary Birth Histories at 1 or 2-year intervals to estimate the mortality rate in that period. SBHs are taken from Brazil's PNAD Surveys 2004-2011 and validated against IGME estimates. 2 of 10 estimates are within 10% of validation estimates. Mean absolute relative error is greater than 100%. Appropriate testing of these new methods demonstrates that they do not produce sufficiently good estimates based on the data available. We conclude this is due to the poor quality of most SBH data included in the study. This has wider implications for the next round of censuses and future household surveys across many low- and middle- income countries.

The Arthroscopic Surgical Skill Evaluation Tool (ASSET).

PubMed

Koehler, Ryan J; Amsdell, Simon; Arendt, Elizabeth A; Bisson, Leslie J; Braman, Jonathan P; Bramen, Jonathan P; Butler, Aaron; Cosgarea, Andrew J; Harner, Christopher D; Garrett, William E; Olson, Tyson; Warme, Winston J; Nicandri, Gregg T

2013-06-01

Surgeries employing arthroscopic techniques are among the most commonly performed in orthopaedic clinical practice; however, valid and reliable methods of assessing the arthroscopic skill of orthopaedic surgeons are lacking. The Arthroscopic Surgery Skill Evaluation Tool (ASSET) will demonstrate content validity, concurrent criterion-oriented validity, and reliability when used to assess the technical ability of surgeons performing diagnostic knee arthroscopic surgery on cadaveric specimens. Cross-sectional study; Level of evidence, 3. Content validity was determined by a group of 7 experts using the Delphi method. Intra-articular performance of a right and left diagnostic knee arthroscopic procedure was recorded for 28 residents and 2 sports medicine fellowship-trained attending surgeons. Surgeon performance was assessed by 2 blinded raters using the ASSET. Concurrent criterion-oriented validity, interrater reliability, and test-retest reliability were evaluated. Content validity: The content development group identified 8 arthroscopic skill domains to evaluate using the ASSET. Concurrent criterion-oriented validity: Significant differences in the total ASSET score (P < .05) between novice, intermediate, and advanced experience groups were identified. Interrater reliability: The ASSET scores assigned by each rater were strongly correlated (r = 0.91, P < .01), and the intraclass correlation coefficient between raters for the total ASSET score was 0.90. Test-retest reliability: There was a significant correlation between ASSET scores for both procedures attempted by each surgeon (r = 0.79, P < .01). The ASSET appears to be a useful, valid, and reliable method for assessing surgeon performance of diagnostic knee arthroscopic surgery in cadaveric specimens. Studies are ongoing to determine its generalizability to other procedures as well as to the live operating room and other simulated environments.

Agreement between Omron 306 and Biospace InBody 720 Bioelectrical Impedance Analyzers (BIA) in Children and Adolescents

ERIC Educational Resources Information Center

Finn, Kevin J.; Saint-Maurice, Pedro F.; Karsai, István; Ihász, Ferenc; Csányi, Tamás

2015-01-01

Purpose: The purpose of this study was to test the convergent validity of Omron 306 using Biospace InBody 720. Method: A total of 267 participants (145 boys; aged 10.4-17.9 years) completed testing during a single session. Each measure provided percent body fat (%BF), while the InBody 720 included fat-free mass (FFM). The validity was examined…

Validity and power of association testing in family-based sampling designs: evidence for and against the common wisdom.

PubMed

Knight, Stacey; Camp, Nicola J

2011-04-01

Current common wisdom posits that association analyses using family-based designs have inflated type 1 error rates (if relationships are ignored) and independent controls are more powerful than familial controls. We explore these suppositions. We show theoretically that family-based designs can have deflated type-error rates. Through simulation, we examine the validity and power of family designs for several scenarios: cases from randomly or selectively ascertained pedigrees; and familial or independent controls. Family structures considered are as follows: sibships, nuclear families, moderate-sized and extended pedigrees. Three methods were considered with the χ(2) test for trend: variance correction (VC), weighted (weights assigned to account for genetic similarity), and naïve (ignoring relatedness) as well as the Modified Quasi-likelihood Score (MQLS) test. Selectively ascertained pedigrees had similar levels of disease enrichment; random ascertainment had no such restriction. Data for 1,000 cases and 1,000 controls were created under the null and alternate models. The VC and MQLS methods were always valid. The naïve method was anti-conservative if independent controls were used and valid or conservative in designs with familial controls. The weighted association method was generally valid for independent controls, and was conservative for familial controls. With regard to power, independent controls were more powerful for small-to-moderate selectively ascertained pedigrees, but familial and independent controls were equivalent in the extended pedigrees and familial controls were consistently more powerful for all randomly ascertained pedigrees. These results suggest a more complex situation than previously assumed, which has important implications for study design and analysis. © 2011 Wiley-Liss, Inc.

Transformation of Developmental Neurotoxicity Data into a Structure-Searchable Relational Database

EPA Science Inventory

A database of neurotoxicants is critical to support the development and validation of animal alternatives for neurotoxicity. Validation of in vitro test methods can only be done using known animal and human neurotoxicants producing defined responses for neurochemical, neuropatho...

Development and Validation of a Computational Model for Androgen Receptor Activity

EPA Science Inventory

Testing thousands of chemicals to identify potential androgen receptor (AR) agonists or antagonists would cost millions of dollars and take decades to complete using current validated methods. High-throughput in vitro screening (HTS) and computational toxicology approaches can mo...

Transferability and inter-laboratory variability assessment of the in vitro bovine oocyte fertilization test.

PubMed

Tessaro, Irene; Modina, Silvia C; Crotti, Gabriella; Franciosi, Federica; Colleoni, Silvia; Lodde, Valentina; Galli, Cesare; Lazzari, Giovanna; Luciano, Alberto M

2015-01-01

The dramatic increase in the number of animals required for reproductive toxicity testing imposes the validation of alternative methods to reduce the use of laboratory animals. As we previously demonstrated for in vitro maturation test of bovine oocytes, the present study describes the transferability assessment and the inter-laboratory variability of an in vitro test able to identify chemical effects during the process of bovine oocyte fertilization. Eight chemicals with well-known toxic properties (benzo[a]pyrene, busulfan, cadmium chloride, cycloheximide, diethylstilbestrol, ketoconazole, methylacetoacetate, mifepristone/RU-486) were tested in two well-trained laboratories. The statistical analysis demonstrated no differences in the EC50 values for each chemical in within (inter-runs) and in between-laboratory variability of the proposed test. We therefore conclude that the bovine in vitro fertilization test could advance toward the validation process as alternative in vitro method and become part of an integrated testing strategy in order to predict chemical hazards on mammalian fertility. Copyright © 2015 Elsevier Inc. All rights reserved.

Measuring verbal and non-verbal communication in aphasia: reliability, validity, and sensitivity to change of the Scenario Test.

PubMed

van der Meulen, Ineke; van de Sandt-Koenderman, W Mieke E; Duivenvoorden, Hugo J; Ribbers, Gerard M

2010-01-01

This study explores the psychometric qualities of the Scenario Test, a new test to assess daily-life communication in severe aphasia. The test is innovative in that it: (1) examines the effectiveness of verbal and non-verbal communication; and (2) assesses patients' communication in an interactive setting, with a supportive communication partner. To determine the reliability, validity, and sensitivity to change of the Scenario Test and discuss its clinical value. The Scenario Test was administered to 122 persons with aphasia after stroke and to 25 non-aphasic controls. Analyses were performed for the entire group of persons with aphasia, as well as for a subgroup of persons unable to communicate verbally (n = 43). Reliability (internal consistency, test-retest reliability, inter-judge, and intra-judge reliability) and validity (internal validity, convergent validity, known-groups validity) and sensitivity to change were examined using standard psychometric methods. The Scenario Test showed high levels of reliability. Internal consistency (Cronbach's alpha = 0.96; item-rest correlations = 0.58-0.82) and test-retest reliability (ICC = 0.98) were high. Agreement between judges in total scores was good, as indicated by the high inter- and intra-judge reliability (ICC = 0.86-1.00). Agreement in scores on the individual items was also good (square-weighted kappa values 0.61-0.92). The test demonstrated good levels of validity. A principal component analysis for categorical data identified two dimensions, interpreted as general communication and communicative creativity. Correlations with three other instruments measuring communication in aphasia, that is, Spontaneous Speech interview from the Aachen Aphasia Test (AAT), Amsterdam-Nijmegen Everyday Language Test (ANELT), and Communicative Effectiveness Index (CETI), were moderate to strong (0.50-0.85) suggesting good convergent validity. Group differences were observed between persons with aphasia and non-aphasic controls, as well as between persons with aphasia unable to use speech to convey information and those able to communicate verbally; this indicates good known-groups validity. The test was sensitive to changes in performance, measured over a period of 6 months. The data support the reliability and validity of the Scenario Test as an instrument for examining daily-life communication in aphasia. The test focuses on multimodal communication; its psychometric qualities enable future studies on the effect of Alternative and Augmentative Communication (AAC) training in aphasia.

An Argument-Based Approach to the Validation of UHTRUST: Can We Measure How Recent Graduates Can Be Trusted with Unfamiliar Tasks?

ERIC Educational Resources Information Center

Wijnen-Meijer, M.; Van der Schaaf, M.; Booij, E.; Harendza, S.; Boscardin, C.; Wijngaarden, J. Van; Ten Cate, Th. J.

2013-01-01

There is a need for valid methods to assess the readiness for clinical practice of medical graduates. This study evaluates the validity of Utrecht Hamburg Trainee Responsibility for Unfamiliar Situations Test (UHTRUST), an authentic simulation procedure to assess whether medical trainees are ready to be entrusted with unfamiliar clinical tasks…

Improving validation methods for molecular diagnostics: application of Bland-Altman, Deming and simple linear regression analyses in assay comparison and evaluation for next-generation sequencing.

PubMed

Misyura, Maksym; Sukhai, Mahadeo A; Kulasignam, Vathany; Zhang, Tong; Kamel-Reid, Suzanne; Stockley, Tracy L

2018-02-01

A standard approach in test evaluation is to compare results of the assay in validation to results from previously validated methods. For quantitative molecular diagnostic assays, comparison of test values is often performed using simple linear regression and the coefficient of determination (R 2 ), using R 2 as the primary metric of assay agreement. However, the use of R 2 alone does not adequately quantify constant or proportional errors required for optimal test evaluation. More extensive statistical approaches, such as Bland-Altman and expanded interpretation of linear regression methods, can be used to more thoroughly compare data from quantitative molecular assays. We present the application of Bland-Altman and linear regression statistical methods to evaluate quantitative outputs from next-generation sequencing assays (NGS). NGS-derived data sets from assay validation experiments were used to demonstrate the utility of the statistical methods. Both Bland-Altman and linear regression were able to detect the presence and magnitude of constant and proportional error in quantitative values of NGS data. Deming linear regression was used in the context of assay comparison studies, while simple linear regression was used to analyse serial dilution data. Bland-Altman statistical approach was also adapted to quantify assay accuracy, including constant and proportional errors, and precision where theoretical and empirical values were known. The complementary application of the statistical methods described in this manuscript enables more extensive evaluation of performance characteristics of quantitative molecular assays, prior to implementation in the clinical molecular laboratory. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Laboratory Analytical Procedures | Bioenergy | NREL

Science.gov Websites

analytical procedures (LAPs) to provide validated methods for biofuels and pyrolysis bio-oils research . Biomass Compositional Analysis These lab procedures provide tested and accepted methods for performing

An approach to operating system testing

NASA Technical Reports Server (NTRS)

Sum, R. N., Jr.; Campbell, R. H.; Kubitz, W. J.

1984-01-01

To ensure the reliability and performance of a new system, it must be verified or validated in some manner. Currently, testing is the only resonable technique available for doing this. Part of this testing process is the high level system test. System testing is considered with respect to operating systems and in particular UNIX. This consideration results in the development and presentation of a good method for performing the system test. The method includes derivations from the system specifications and ideas for management of the system testing project. Results of applying the method to the IBM System/9000 XENIX operating system test and the development of a UNIX test suite are presented.

WEC-SIM Validation Testing Plan FY14 Q4.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruehl, Kelley Michelle

2016-02-01

The WEC-Sim project is currently on track, having met both the SNL and NREL FY14 Milestones, as shown in Table 1 and Table 2. This is also reflected in the Gantt chart uploaded to the WEC-Sim SharePoint site in the FY14 Q4 Deliverables folder. The work completed in FY14 includes code verification through code-to-code comparison (FY14 Q1 and Q2), preliminary code validation through comparison to experimental data (FY14 Q2 and Q3), presentation and publication of the WEC-Sim project at OMAE 2014 [1], [2], [3] and GMREC/METS 2014 [4] (FY14 Q3), WEC-Sim code development and public open-source release (FY14 Q3), andmore » development of a preliminary WEC-Sim validation test plan (FY14 Q4). This report presents the preliminary Validation Testing Plan developed in FY14 Q4. The validation test effort started in FY14 Q4 and will go on through FY15. Thus far the team has developed a device selection method, selected a device, and placed a contract with the testing facility, established several collaborations including industry contacts, and have working ideas on the testing details such as scaling, device design, and test conditions.« less

Zero-G experimental validation of a robotics-based inertia identification algorithm

NASA Astrophysics Data System (ADS)

Bruggemann, Jeremy J.; Ferrel, Ivann; Martinez, Gerardo; Xie, Pu; Ma, Ou

2010-04-01

The need to efficiently identify the changing inertial properties of on-orbit spacecraft is becoming more critical as satellite on-orbit services, such as refueling and repairing, become increasingly aggressive and complex. This need stems from the fact that a spacecraft's control system relies on the knowledge of the spacecraft's inertia parameters. However, the inertia parameters may change during flight for reasons such as fuel usage, payload deployment or retrieval, and docking/capturing operations. New Mexico State University's Dynamics, Controls, and Robotics Research Group has proposed a robotics-based method of identifying unknown spacecraft inertia properties1. Previous methods require firing known thrusts then measuring the thrust, and the velocity and acceleration changes. The new method utilizes the concept of momentum conservation, while employing a robotic device powered by renewable energy to excite the state of the satellite. Thus, it requires no fuel usage or force and acceleration measurements. The method has been well studied in theory and demonstrated by simulation. However its experimental validation is challenging because a 6- degree-of-freedom motion in a zero-gravity condition is required. This paper presents an on-going effort to test the inertia identification method onboard the NASA zero-G aircraft. The design and capability of the test unit will be discussed in addition to the flight data. This paper also introduces the design and development of an airbearing based test used to partially validate the method, in addition to the approach used to obtain reference value for the test system's inertia parameters that can be used for comparison with the algorithm results.

Validity and reliability of the abdominal test and evaluation systems tool (ABTEST) to accurately measure abdominal force.

PubMed

Glenn, Jordan M; Galey, Madeline; Edwards, Abigail; Rickert, Bradley; Washington, Tyrone A

2015-07-01

Ability to generate force from the core musculature is a critical factor for sports and general activities with insufficiencies predisposing individuals to injury. This study evaluated isometric force production as a valid and reliable method of assessing abdominal force using the abdominal test and evaluation systems tool (ABTEST). Secondary analysis estimated 1-repetition maximum on commercially available abdominal machine compared to maximum force and average power on ABTEST system. This study utilized test-retest reliability and comparative analysis for validity. Reliability was measured using test-retest design on ABTEST. Validity was measured via comparison to estimated 1-repetition maximum on a commercially available abdominal device. Participants applied isometric, abdominal force against a transducer and muscular activation was evaluated measuring normalized electromyographic activity at the rectus-abdominus, rectus-femoris, and erector-spinae. Test, re-test force production on ABTEST was significantly correlated (r=0.84; p<0.001). Mean electromyographic activity for the rectus-abdominus (72.93% and 75.66%), rectus-femoris (6.59% and 6.51%), and erector-spinae (6.82% and 5.48%) were observed for trial-1 and trial-2, respectively. Significant correlations for the estimated 1-repetition maximum were found for average power (r=0.70, p=0.002) and maximum force (r=0.72, p<0.001). Data indicate the ABTEST can accurately measure rectus-abdominus force isolated from hip-flexor involvement. Negligible activation of erector-spinae substantiates little subjective effort among participants in the lower back. Results suggest ABTEST is a valid and reliable method of evaluating abdominal force. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Test method research on weakening interface strength of steel - concrete under cyclic loading

NASA Astrophysics Data System (ADS)

Liu, Ming-wei; Zhang, Fang-hua; Su, Guang-quan

2018-02-01

The mechanical properties of steel - concrete interface under cyclic loading are the key factors affecting the rule of horizontal load transfer, the calculation of bearing capacity and cumulative horizontal deformation. Cyclic shear test is an effective method to study the strength reduction of steel - concrete interface. A test system composed of large repeated direct shear test instrument, hydraulic servo system, data acquisition system, test control software system and so on is independently designed, and a set of test method, including the specimen preparation, the instrument preparation, the loading method and so on, is put forward. By listing a set of test results, the validity of the test method is verified. The test system and the test method based on it provide a reference for the experimental study on mechanical properties of steel - concrete interface.

Psychometric instrumentation: reliability and validity of instruments used for clinical practice, evidence-based practice projects and research studies.

PubMed

Mayo, Ann M

2015-01-01

It is important for CNSs and other APNs to consider the reliability and validity of instruments chosen for clinical practice, evidence-based practice projects, or research studies. Psychometric testing uses specific research methods to evaluate the amount of error associated with any particular instrument. Reliability estimates explain more about how well the instrument is designed, whereas validity estimates explain more about scores that are produced by the instrument. An instrument may be architecturally sound overall (reliable), but the same instrument may not be valid. For example, if a specific group does not understand certain well-constructed items, then the instrument does not produce valid scores when used with that group. Many instrument developers may conduct reliability testing only once, yet continue validity testing in different populations over many years. All CNSs should be advocating for the use of reliable instruments that produce valid results. Clinical nurse specialists may find themselves in situations where reliability and validity estimates for some instruments that are being utilized are unknown. In such cases, CNSs should engage key stakeholders to sponsor nursing researchers to pursue this most important work.

Analysis of small sample size studies using nonparametric bootstrap test with pooled resampling method.

PubMed

Dwivedi, Alok Kumar; Mallawaarachchi, Indika; Alvarado, Luis A

2017-06-30

Experimental studies in biomedical research frequently pose analytical problems related to small sample size. In such studies, there are conflicting findings regarding the choice of parametric and nonparametric analysis, especially with non-normal data. In such instances, some methodologists questioned the validity of parametric tests and suggested nonparametric tests. In contrast, other methodologists found nonparametric tests to be too conservative and less powerful and thus preferred using parametric tests. Some researchers have recommended using a bootstrap test; however, this method also has small sample size limitation. We used a pooled method in nonparametric bootstrap test that may overcome the problem related with small samples in hypothesis testing. The present study compared nonparametric bootstrap test with pooled resampling method corresponding to parametric, nonparametric, and permutation tests through extensive simulations under various conditions and using real data examples. The nonparametric pooled bootstrap t-test provided equal or greater power for comparing two means as compared with unpaired t-test, Welch t-test, Wilcoxon rank sum test, and permutation test while maintaining type I error probability for any conditions except for Cauchy and extreme variable lognormal distributions. In such cases, we suggest using an exact Wilcoxon rank sum test. Nonparametric bootstrap paired t-test also provided better performance than other alternatives. Nonparametric bootstrap test provided benefit over exact Kruskal-Wallis test. We suggest using nonparametric bootstrap test with pooled resampling method for comparing paired or unpaired means and for validating the one way analysis of variance test results for non-normal data in small sample size studies. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Validation of RNAi Silencing Efficiency Using Gene Array Data shows 18.5% Failure Rate across 429 Independent Experiments.

PubMed

Munkácsy, Gyöngyi; Sztupinszki, Zsófia; Herman, Péter; Bán, Bence; Pénzváltó, Zsófia; Szarvas, Nóra; Győrffy, Balázs

2016-09-27

No independent cross-validation of success rate for studies utilizing small interfering RNA (siRNA) for gene silencing has been completed before. To assess the influence of experimental parameters like cell line, transfection technique, validation method, and type of control, we have to validate these in a large set of studies. We utilized gene chip data published for siRNA experiments to assess success rate and to compare methods used in these experiments. We searched NCBI GEO for samples with whole transcriptome analysis before and after gene silencing and evaluated the efficiency for the target and off-target genes using the array-based expression data. Wilcoxon signed-rank test was used to assess silencing efficacy and Kruskal-Wallis tests and Spearman rank correlation were used to evaluate study parameters. All together 1,643 samples representing 429 experiments published in 207 studies were evaluated. The fold change (FC) of down-regulation of the target gene was above 0.7 in 18.5% and was above 0.5 in 38.7% of experiments. Silencing efficiency was lowest in MCF7 and highest in SW480 cells (FC = 0.59 and FC = 0.30, respectively, P = 9.3E-06). Studies utilizing Western blot for validation performed better than those with quantitative polymerase chain reaction (qPCR) or microarray (FC = 0.43, FC = 0.47, and FC = 0.55, respectively, P = 2.8E-04). There was no correlation between type of control, transfection method, publication year, and silencing efficiency. Although gene silencing is a robust feature successfully cross-validated in the majority of experiments, efficiency remained insufficient in a significant proportion of studies. Selection of cell line model and validation method had the highest influence on silencing proficiency.

The predictive validity of selection for entry into postgraduate training in general practice: evidence from three longitudinal studies.

PubMed

Patterson, Fiona; Lievens, Filip; Kerrin, Máire; Munro, Neil; Irish, Bill

2013-11-01

The selection methodology for UK general practice is designed to accommodate several thousand applicants per year and targets six core attributes identified in a multi-method job-analysis study To evaluate the predictive validity of selection methods for entry into postgraduate training, comprising a clinical problem-solving test, a situational judgement test, and a selection centre. A three-part longitudinal predictive validity study of selection into training for UK general practice. In sample 1, participants were junior doctors applying for training in general practice (n = 6824). In sample 2, participants were GP registrars 1 year into training (n = 196). In sample 3, participants were GP registrars sitting the licensing examination after 3 years, at the end of training (n = 2292). The outcome measures include: assessor ratings of performance in a selection centre comprising job simulation exercises (sample 1); supervisor ratings of trainee job performance 1 year into training (sample 2); and licensing examination results, including an applied knowledge examination and a 12-station clinical skills objective structured clinical examination (OSCE; sample 3). Performance ratings at selection predicted subsequent supervisor ratings of job performance 1 year later. Selection results also significantly predicted performance on both the clinical skills OSCE and applied knowledge examination for licensing at the end of training. In combination, these longitudinal findings provide good evidence of the predictive validity of the selection methods, and are the first reported for entry into postgraduate training. Results show that the best predictor of work performance and training outcomes is a combination of a clinical problem-solving test, a situational judgement test, and a selection centre. Implications for selection methods for all postgraduate specialties are considered.

Developing the Persian version of the homophone meaning generation test

PubMed Central

Ebrahimipour, Mona; Motamed, Mohammad Reza; Ashayeri, Hassan; Modarresi, Yahya; Kamali, Mohammad

2016-01-01

Background: Finding the right word is a necessity in communication, and its evaluation has always been a challenging clinical issue, suggesting the need for valid and reliable measurements. The Homophone Meaning Generation Test (HMGT) can measure the ability to switch between verbal concepts, which is required in word retrieval. The purpose of this study was to adapt and validate the Persian version of the HMGT. Methods: The first phase involved the adaptation of the HMGT to the Persian language. The second phase concerned the psychometric testing. The word-finding performance was assessed in 90 Persian-speaking healthy individuals (20-50 year old; 45 males and 45 females) through three naming tasks: Semantic Fluency, Phonemic Fluency, and Homophone Meaning Generation Test. The participants had no history of neurological or psychiatric diseases, alcohol abuse, severe depression, or history of speech, language, or learning problems. Results: The internal consistency coefficient was larger than 0.8 for all the items with a total Cronbach’s alpha of 0.80. Interrater and intrarater reliability were also excellent. The validity of all items was above 0.77, and the content validity index (0.99) was appropriate. The Persian HMGT had strong convergent validity with semantic and phonemic switching and adequate divergent validity with semantic and phonemic clustering. Conclusion: The Persian version of the Homophone Meaning Generation Test is an appropriate, valid, and reliable test to evaluate the ability to switch between verbal concepts in the assessment of word-finding performance. PMID:27390705

The validation of Huffaz Intelligence Test (HIT)

NASA Astrophysics Data System (ADS)

Rahim, Mohd Azrin Mohammad; Ahmad, Tahir; Awang, Siti Rahmah; Safar, Ajmain

2017-08-01

In general, a hafiz who can memorize the Quran has many specialties especially in respect to their academic performances. In this study, the theory of multiple intelligences introduced by Howard Gardner is embedded in a developed psychometric instrument, namely Huffaz Intelligence Test (HIT). This paper presents the validation and the reliability of HIT of some tahfiz students in Malaysia Islamic schools. A pilot study was conducted involving 87 huffaz who were randomly selected to answer the items in HIT. The analysis method used includes Partial Least Square (PLS) on reliability, convergence and discriminant validation. The study has validated nine intelligences. The findings also indicated that the composite reliabilities for the nine types of intelligences are greater than 0.8. Thus, the HIT is a valid and reliable instrument to measure the multiple intelligences among huffaz.

45 CFR 1388.6 - Program criteria-services and supports.

Code of Federal Regulations, 2011 CFR

2011-10-01

... according to accepted practices of scientific evaluation; (iv) Research methods that are used to test hypotheses, validate procedures, and field test projects; and (v) Direct service and project practices and...

An investigation of new toxicity test method performance in validation studies: 1. Toxicity test methods that have predictive capacity no greater than chance.

PubMed

Bruner, L H; Carr, G J; Harbell, J W; Curren, R D

2002-06-01

An approach commonly used to measure new toxicity test method (NTM) performance in validation studies is to divide toxicity results into positive and negative classifications, and the identify true positive (TP), true negative (TN), false positive (FP) and false negative (FN) results. After this step is completed, the contingent probability statistics (CPS), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) are calculated. Although these statistics are widely used and often the only statistics used to assess the performance of toxicity test methods, there is little specific guidance in the validation literature on what values for these statistics indicate adequate performance. The purpose of this study was to begin developing data-based answers to this question by characterizing the CPS obtained from an NTM whose data have a completely random association with a reference test method (RTM). Determining the CPS of this worst-case scenario is useful because it provides a lower baseline from which the performance of an NTM can be judged in future validation studies. It also provides an indication of relationships in the CPS that help identify random or near-random relationships in the data. The results from this study of randomly associated tests show that the values obtained for the statistics vary significantly depending on the cut-offs chosen, that high values can be obtained for individual statistics, and that the different measures cannot be considered independently when evaluating the performance of an NTM. When the association between results of an NTM and RTM is random the sum of the complementary pairs of statistics (sensitivity + specificity, NPV + PPV) is approximately 1, and the prevalence (i.e., the proportion of toxic chemicals in the population of chemicals) and PPV are equal. Given that combinations of high sensitivity-low specificity or low specificity-high sensitivity (i.e., the sum of the sensitivity and specificity equal to approximately 1) indicate lack of predictive capacity, an NTM having these performance characteristics should be considered no better for predicting toxicity than by chance alone.

Reliability and Validity of the Chinese (Mandarin) Tinnitus Handicap Inventory

PubMed Central

Meng, Zhaoli; Zheng, Yun; Wang, Kai; Kong, Xiudan; Tao, Yong; Xu, Ke; Liu, Guanjian

2012-01-01

Objectives The Tinnitus Handicap Inventory (THI) is a commonly used self-reporting tinnitus questionnaire. We undertook this study to determine the reliability and validity of the Chinese-Mandarin version of the Tinnitus Handicap Inventory (THI-CM) for measuring tinnitus-related handicaps. Methods We tested the test-retest reliability, internal reliability, and construct validity of the THI-CM. Two-hundred patients seeking treatment for primary or secondary tinnitus in Southwest China were asked to complete THI-CM prior to clinical evaluation. Patients were evaluated by a clinician using standard methods, and 40 patients were asked to complete THI-CM a second time 14±3 days after the initial interview. Results The test-retest reliability of THI-CM was high (Pearson correlation, 0.98), as was the internal reliability (Cronbach's α, 0.93). Factor analysis indicated that THI-CM has a unifactorial structure. Conclusion The THI-CM version is reliable. The total score in THI-CM can be used to measure tinnitus-related handicaps in Mandarin-speaking populations. PMID:22468196

Quantitative bioanalysis of strontium in human serum by inductively coupled plasma-mass spectrometry

PubMed Central

Somarouthu, Srikanth; Ohh, Jayoung; Shaked, Jonathan; Cunico, Robert L; Yakatan, Gerald; Corritori, Suzana; Tami, Joe; Foehr, Erik D

2015-01-01

Aim: A bioanalytical method using inductively-coupled plasma-mass spectrometry to measure endogenous levels of strontium in human serum was developed and validated. Results & methodology: This article details the experimental procedures used for the method development and validation thus demonstrating the application of the inductively-coupled plasma-mass spectrometry method for quantification of strontium in human serum samples. The assay was validated for specificity, linearity, accuracy, precision, recovery and stability. Significant endogenous levels of strontium are present in human serum samples ranging from 19 to 96 ng/ml with a mean of 34.6 ± 15.2 ng/ml (SD). Discussion & conclusion: Calibration procedures and sample pretreatment were simplified for high throughput analysis. The validation demonstrates that the method was sensitive, selective for quantification of strontium (88Sr) and is suitable for routine clinical testing of strontium in human serum samples. PMID:28031925

Skin-electrode impedance measurement during ECG acquisition: method’s validation

NASA Astrophysics Data System (ADS)

Casal, Leonardo; La Mura, Guillermo

2016-04-01

Skm-electrode impedance measurement can provide valuable information prior. dunng and post electrocardiographic (ECG) or electroencephalographs (EEG) acquisitions. In this work we validate a method for skm-electrode impedance measurement using test circuits with known resistance and capacitor values, at different frequencies for injected excitation current. Finally the method is successfully used for impedance measurement during ECG acquisition on a subject usmg 125 Hz and 6 nA square wave excitation signal at instrumentation amplifier mput. The method can be used for many electrodes configuration.

Development and validation of a dissolution test for lodenafil carbonate based on in vivo data.

PubMed

Codevilla, Cristiane Franco; Castilhos, Tamara dos Santos; Cirne, Carolina Araújo; Froehlich, Pedro Eduardo; Bergold, Ana Maria

2014-04-01

Lodenafil carbonate is a phosphodiesterase type 5 inhibitor used for the treatment of erectile dysfunction. Currently, there is no dissolution test reported for lodenafil carbonate and this drug is not listed in any pharmacopoeia. The present study focused on the development and validation of a dissolution test for lodenafil carbonate tablets, using a simulated absorption profile based on in vivo data. The appropriate conditions were determined after testing sink conditions. Different conditions as medium, surfactant concentration and rotation speed were evaluated. The percentage of dose absorbed was calculated by deconvolution, using the Wagner-Nelson method. According to the obtained results, the use of 0.1 M HCl + 1.5% SLS (900 mL, at 37 + 0.5 °C) as the dissolution medium, paddles at 25 rpm were considered adequate. The samples were quantified by UV spectroscopy at 295 nm and the validation was performed according to international guidelines. The method showed specificity, linearity, accuracy and precision, within the acceptable range. Kinetics of drug release was better described by the first-order model. The proposed dissolution test can be used for the routine quality control of lodenafil carbonate in tablets.

Successful validation of in vitro methods in toxicology by ZEBET, the National Centre for Alternatives in Germany at the BfR (Federal Institute for Risk Assessment).

PubMed

Spielmann, Horst; Grune, Barbara; Liebsch, Manfred; Seiler, Andrea; Vogel, Richard

2008-06-01

A short description of the history of the 3Rs concept is given, which was developed as the scientific concept to refine, reduce and replace animal experiments by Russel and Burch more than 40 years ago. In addition, the legal framework in Europe for developing alternatives to animal experiments is given and the current status of in vitro systems in pharmacology and toxicology is described including an update on metabolising systems. The decrease in experimental animal numbers during the past decade in Europe is illustrated by the situation in Germany and the contribution of international harmonisation of test guidelines on reducing animal numbers in regulatory testing is described. A review of the development of the principles of experimental validation is given and the 3T3 NRU in vitro phototoxicity test is used as an example for a successful validation study, which led to the acceptance of the first in vitro toxicity test for regulatory purposes by the OECD. Finally, the currently accepted alternative methods for standardisation and safety testing of drugs, biologicals and medical devices are summarised.

Reliability, Validity, and Cross-Cultural Adaptation of the Turkish Version of the Bournemouth Questionnaire.

PubMed

Gunaydin, Gurkan; Citaker, Seyit; Meray, Jale; Cobanoglu, Gamze; Gunaydin, Ozge Ece; Hazar Kanik, Zeynep

2016-11-01

Validation of a self-report questionnaire. The purpose of this study was to investigate adaptation, validity, and reliability of the Turkish version of the Bournemouth Questionnaire. Low back pain is one of the most frequent disorders leading to activity limitation. This pain affects most of people in their lives. The most important point to evaluate patient's functional abilities and to decide a successful therapy procedure is to manage the assessment questionnaires precisely. One hundred ten patients with chronic low back pain were included in present study. To assess reliability, test-retest and internal consistency analyses were applied. The results of test-retest analysis were assessed by using Intraclass Correlation Coefficient method (95% confidence interval). For internal consistency, Cronbach alpha value was calculated. Validity of the questionnaire was assessed in terms of construct validity. For construct validity, factor analysis and convergent validity were tested. For convergent validity, total points of the Bournemouth Questionnaire were assessed with the total points of Quebec Back Pain Disability Scale and Roland Morris Disability Questionnaire by using Pearson correlation coefficient analysis. Cronbach alpha value was found 0.914, showing that this questionnaire has high internal consistency. The results of test-retest analysis were varying between 0.851 and 0.927, which shows that test-retest results are highly correlated. Factor analysis test indicated that this questionnaire had one factor. Pearson correlation coefficient of the Bournemouth Questionnaire with Roland Morris Disability Questionnaire was calculated 0.703 and it was found with Quebec Back Pain Disability Scale is 0.659. These results showed that the Bournemouth Questionnaire is very good correlated with Roland Morris Disability Questionnaire and Quebec Back Pain Disability Scale. The Turkish version of the Bournemouth Questionnaire is valid and reliable. 3.

Psychometric Evaluation of the Revised Michigan Diabetes Knowledge Test (V.2016) in Arabic: Translation and Validation

PubMed Central

Alhaiti, Ali Hassan; Alotaibi, Alanod Raffa; Jones, Linda Katherine; DaCosta, Cliff

2016-01-01

Objective. To translate the revised Michigan Diabetes Knowledge Test into the Arabic language and examine its psychometric properties. Setting. Of the 139 participants recruited through King Fahad Medical City in Riyadh, Saudi Arabia, 34 agreed to the second-round sample for retesting purposes. Methods. The translation process followed the World Health Organization's guidelines for the translation and adaptation of instruments. All translations were examined for their validity and reliability. Results. The translation process revealed excellent results throughout all stages. The Arabic version received 0.75 for internal consistency via Cronbach's alpha test and excellent outcomes in terms of the test-retest reliability of the instrument with a mean of 0.90 infraclass correlation coefficient. It also received positive content validity index scores. The item-level content validity index for all instrument scales fell between 0.83 and 1 with a mean scale-level index of 0.96. Conclusion. The Arabic version is proven to be a reliable and valid measure of patient's knowledge that is ready to be used in clinical practices. PMID:27995149

Validity and everyday clinical applicability of lumbar muscle fatigue assessment methods in patients with chronic non-specific low back pain: a systematic review.

PubMed

Villafañe, Jorge H; Gobbo, Massimiliano; Peranzoni, Matteo; Naik, Ganesh; Imperio, Grace; Cleland, Joshua A; Negrini, Stefano

2016-09-01

This systematic literature review aimed at examining the validity and applicability in everyday clinical rehabilitation practise of methods for the assessment of back muscle fatiguability in patients with chronic non-specific low back pain (CNSLBP). Extensive research was performed in MEDLINE, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Embase, Physiotherapy Evidence Database (PEDro) and Cochrane Central Register of Controlled Trials (CENTRAL) databases from their inception to September 2014. Potentially relevant articles were also manually looked for in the reference lists of the identified publications. Studies examining lumbar muscle fatigue in people with CNSLBP were selected. Two reviewers independently selected the articles, carried out the study quality assessment and extracted the results. A modified Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) scale was used to evaluate the scientific rigour of the selected works. Twenty-four studies fulfilled the selection criteria and were included in the systematic review. We found conflicting data regarding the validity of methods used to examine back muscle fatigue. The Biering-Sorensen test, performed in conjunction with surface electromyography spectral analysis, turned out to be the most widely used and comparatively, the most optimal modality currently available to assess objective back muscle fatigue in daily clinical practise, even though critical limitations are discussed. Future research should address the identification of an advanced method for lower back fatigue assessment in patients with CNSLBP which, eventually, might provide physical therapists with an objective and reliable test usable in everyday clinical practise. Implications for Rehabilitation Despite its limitations, the Biering-Sorensen test is currently the most used, convenient and easily available fatiguing test for lumbar muscles. To increase validity and reliability of the Biering-Sorensen test, concomitant activation of synergistic muscles should be taken into account. Pooled mean frequency and half-width of the spectrum are currently the most valid electromyographic parameters to assess fatigue in chronic non-specific low back pain. Body mass index, grading of pain and level of disability of the study population should be reported to enhance research quality.

Test-retest reliability and construct validity of the ENERGY-child questionnaire on energy balance-related behaviours and their potential determinants: the ENERGY-project

PubMed Central

2011-01-01

Background Insight in children's energy balance-related behaviours (EBRBs) and their determinants is important to inform obesity prevention research. Therefore, reliable and valid tools to measure these variables in large-scale population research are needed. Objective To examine the test-retest reliability and construct validity of the child questionnaire used in the ENERGY-project, measuring EBRBs and their potential determinants among 10-12 year old children. Methods We collected data among 10-12 year old children (n = 730 in the test-retest reliability study; n = 96 in the construct validity study) in six European countries, i.e. Belgium, Greece, Hungary, the Netherlands, Norway, and Spain. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC) and percentage agreement comparing scores from two measurements, administered one week apart. To assess construct validity, the agreement between questionnaire responses and a subsequent face-to-face interview was assessed using ICC and percentage agreement. Results Of the 150 questionnaire items, 115 (77%) showed good to excellent test-retest reliability as indicated by ICCs > .60 or percentage agreement ≥ 75%. Test-retest reliability was moderate for 34 items (23%) and poor for one item. Construct validity appeared to be good to excellent for 70 (47%) of the 150 items, as indicated by ICCs > .60 or percentage agreement ≥ 75%. From the other 80 items, construct validity was moderate for 39 (26%) and poor for 41 items (27%). Conclusions Our results demonstrate that the ENERGY-child questionnaire, assessing EBRBs of the child as well as personal, family, and school-environmental determinants related to these EBRBs, has good test-retest reliability and moderate to good construct validity for the large majority of items. PMID:22152048

Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-05-29

Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Methodological and cross sectional study. A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain.

The ad-libitum alcohol 'taste test': secondary analyses of potential confounds and construct validity.

PubMed

Jones, Andrew; Button, Emily; Rose, Abigail K; Robinson, Eric; Christiansen, Paul; Di Lemma, Lisa; Field, Matt

2016-03-01

Motivation to drink alcohol can be measured in the laboratory using an ad-libitum 'taste test', in which participants rate the taste of alcoholic drinks whilst their intake is covertly monitored. Little is known about the construct validity of this paradigm. The objective of this study was to investigate variables that may compromise the validity of this paradigm and its construct validity. We re-analysed data from 12 studies from our laboratory that incorporated an ad-libitum taste test. We considered time of day and participants' awareness of the purpose of the taste test as potential confounding variables. We examined whether gender, typical alcohol consumption, subjective craving, scores on the Alcohol Use Disorders Identification Test and perceived pleasantness of the drinks predicted ad-libitum consumption (construct validity). We included 762 participants (462 female). Participant awareness and time of day were not related to ad-libitum alcohol consumption. Males drank significantly more alcohol than females (p < 0.001), and individual differences in typical alcohol consumption (p = 0.04), craving (p < 0.001) and perceived pleasantness of the drinks (p = 0.04) were all significant predictors of ad-libitum consumption. We found little evidence that time of day or participant awareness influenced alcohol consumption. The construct validity of the taste test was supported by relationships between ad-libitum consumption and typical alcohol consumption, craving and pleasantness ratings of the drinks. The ad-libitum taste test is a valid method for the assessment of alcohol intake in the laboratory.

A Review of the Proposed KIsi Offset-Secant Method for Size-Insensitive Linear-Elastic Fracture Toughness Evaluation

NASA Technical Reports Server (NTRS)

James, Mark; Wells, Doug; Allen, Phillip; Wallin, Kim

2017-01-01

Recently proposed modifications to ASTM E399 would provide a new size-insensitive approach to analyzing the force-displacement test record. The proposed size-insensitive linear-elastic fracture toughness, KIsi, targets a consistent 0.5mm crack extension for all specimen sizes by using an offset secant that is a function of the specimen ligament length. The KIsi evaluation also removes the Pmax/PQ criterion and increases the allowable specimen deformation. These latter two changes allow more plasticity at the crack tip, prompting the review undertaken in this work to ensure the validity of this new interpretation of the force-displacement curve. This paper provides a brief review of the proposed KIsi methodology and summarizes a finite element study into the effects of increased crack tip plasticity on the method given the allowance for additional specimen deformation. The study has two primary points of investigation: the effect of crack tip plasticity on compliance change in the force-displacement record and the continued validity of linear-elastic fracture mechanics to describe the crack front conditions. The analytical study illustrates that linear-elastic fracture mechanics assumptions remain valid at the increased deformation limit; however, the influence of plasticity on the compliance change in the test record is problematic. A proposed revision to the validity criteria for the KIsi test method is briefly discussed.

Towards a conceptual framework demonstrating the effectiveness of audiovisual patient descriptions (patient video cases): a review of the current literature

PubMed Central

2012-01-01

Background Technological advances have enabled the widespread use of video cases via web-streaming and online download as an educational medium. The use of real subjects to demonstrate acute pathology should aid the education of health care professionals. However, the methodology by which this effect may be tested is not clear. Methods We undertook a literature review of major databases, found relevant articles relevant to using patient video cases as educational interventions, extracted the methodologies used and assessed these methods for internal and construct validity. Results A review of 2532 abstracts revealed 23 studies meeting the inclusion criteria and a final review of 18 of relevance. Medical students were the most commonly studied group (10 articles) with a spread of learner satisfaction, knowledge and behaviour tested. Only two of the studies fulfilled defined criteria on achieving internal and construct validity. The heterogeneity of articles meant it was not possible to perform any meta-analysis. Conclusions Previous studies have not well classified which facet of training or educational outcome the study is aiming to explore and had poor internal and construct validity. Future research should aim to validate a particular outcome measure, preferably by reproducing previous work rather than adopting new methods. In particular cognitive processing enhancement, demonstrated in a number of the medical student studies, should be tested at a postgraduate level. PMID:23256787

K(3)EDTA Vacuum Tubes Validation for Routine Hematological Testing.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K(3)EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K(3)EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests.

K3EDTA Vacuum Tubes Validation for Routine Hematological Testing

PubMed Central

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K3EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K3EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests. PMID:22888448

Evaluation of p-phenylenediamine, o-phenylphenol sodium salt, and 2,4-diaminotoluene in the rat comet assay as part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiated international validation study of in vivo rat alkaline comet assay.

PubMed

De Boeck, Marlies; van der Leede, Bas-jan; De Vlieger, Kathleen; Geys, Helena; Vynckier, An; Van Gompel, Jacky

2015-07-01

As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiated international validation study of in vivo rat alkaline comet assay (comet assay), p-phenylenediamine dihydrochloride (PPD), o-phenylphenol sodium salt (OPP), and 2,4-diaminotoluene (2,4-DAT), were analyzed in this laboratory as coded test chemicals. Male Sprague-Dawley rats (7-9 weeks of age) were given three oral doses of the test compounds, 24 and 21 h apart and liver and stomach were sampled 3h after the final dose administration. Under the conditions of the test, no increases in DNA damage were observed in liver and stomach with PPD and OPP up to 100 and 1000 mg/kg/day, respectively. 2,4-DAT, a known genotoxic carcinogen, induced a weak but reproducible, dose-related and statistically significant increase in DNA damage in liver cells while no increases were observed in stomach cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Reliability and Validity of a New Method for Isometric Back Extensor Strength Evaluation Using A Hand-Held Dynamometer.

PubMed

Park, Hee-Won; Baek, Sora; Kim, Hong Young; Park, Jung-Gyoo; Kang, Eun Kyoung

2017-10-01

To investigate the reliability and validity of a new method for isometric back extensor strength measurement using a portable dynamometer. A chair equipped with a small portable dynamometer was designed (Power Track II Commander Muscle Tester). A total of 15 men (mean age, 34.8±7.5 years) and 15 women (mean age, 33.1±5.5 years) with no current back problems or previous history of back surgery were recruited. Subjects were asked to push the back of the chair while seated, and their isometric back extensor strength was measured by the portable dynamometer. Test-retest reliability was assessed with intraclass correlation coefficient (ICC). For the validity assessment, isometric back extensor strength of all subjects was measured by a widely used physical performance evaluation instrument, BTE PrimusRS system. The limit of agreement (LoA) from the Bland-Altman plot was evaluated between two methods. The test-retest reliability was excellent (ICC=0.82; 95% confidence interval, 0.65-0.91). The Bland-Altman plots demonstrated acceptable agreement between the two methods: the lower 95% LoA was -63.1 N and the upper 95% LoA was 61.1 N. This study shows that isometric back extensor strength measurement using a portable dynamometer has good reliability and validity.

Why the Major Field Test in Business Does Not Report Subscores: Reliability and Construct Validity Evidence. Research Report. ETS RR-12-11

ERIC Educational Resources Information Center

Ling, Guangming

2012-01-01

To assess the value of individual students' subscores on the Major Field Test in Business (MFT Business), I examined the test's internal structure with factor analysis and structural equation model methods, and analyzed the subscore reliabilities using the augmented scores method. Analyses of the internal structure suggested that the MFT Business…

Attitudes about Advances in Sweat Patch Testing in Drug Courts: Insights from a Case Study in Southern California

ERIC Educational Resources Information Center

Polzer, Katherine

2010-01-01

Drug courts are reinventing the drug testing framework by experimenting with new methods, including use of the sweat patch. The sweat patch is a band-aid like strip used to monitor drug court participants. The validity and reliability of the sweat patch as an effective testing method was examined, as well as the effectiveness, meaning how likely…

Experience with Aero- and Fluid-Dynamic Testing for Engineering and CFD Validation

NASA Technical Reports Server (NTRS)

Ross, James C.

2016-01-01

Ever since computations have been used to simulate aerodynamics the need to ensure that the computations adequately represent real life has followed. Many experiments have been performed specifically for validation and as computational methods have improved, so have the validation experiments. Validation is also a moving target because computational methods improve requiring validation for the new aspect of flow physics that the computations aim to capture. Concurrently, new measurement techniques are being developed that can help capture more detailed flow features pressure sensitive paint (PSP) and particle image velocimetry (PIV) come to mind. This paper will present various wind-tunnel tests the author has been involved with and how they were used for validation of various kinds of CFD. A particular focus is the application of advanced measurement techniques to flow fields (and geometries) that had proven to be difficult to predict computationally. Many of these difficult flow problems arose from engineering and development problems that needed to be solved for a particular vehicle or research program. In some cases the experiments required to solve the engineering problems were refined to provide valuable CFD validation data in addition to the primary engineering data. All of these experiments have provided physical insight and validation data for a wide range of aerodynamic and acoustic phenomena for vehicles ranging from tractor-trailers to crewed spacecraft.

77 FR 61610 - Interagency Coordinating Committee on the Validation of Alternative Methods Evaluation Report and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-10

... Chemical Eye Hazards With Fewer Animals; Availability of Report; Notice of Transmittal to Federal Agencies... (ICCVAM) test method evaluation report (TMER) that provides recommendations for identifying chemical eye... animals in a three-animal test to identify chemicals and products that are eye hazards will maintain...

Willingness to pay function for two fuel treatments to reduce wildfire acreage burned: A scope test and comparison of White and Hispanic households

Treesearch

John B. Loomis; Le Trong Hung; Armando Gonzalez-Caban

2009-01-01

This research uses the Contingent Valuation Method to test whether willingness to pay increases for larger reductions in acres of forests burned by wildfires across the states of California. Florida and Montana. This is known as a test of scope, a measure of internal validity of the contingent valuation method (CVM). The scope test is conducted separately for White...

HEATED PURGE AND TRAP METHOD DEVELOPMENT AND TESTING

EPA Science Inventory

The goal of the research was to develop a heated purge and trap method that could be used in conjunction with SW-846 method 8240 for the analysis of volatile, water soluble Appendix VIII analytes. The developed method was validated according to a partial single laboratory method ...

Sensitivity of different Trypanosoma vivax specific primers for the diagnosis of livestock trypanosomosis using different DNA extraction methods.

PubMed

Gonzales, J L; Loza, A; Chacon, E

2006-03-15

There are several T. vivax specific primers developed for PCR diagnosis. Most of these primers were validated under different DNA extraction methods and study designs leading to heterogeneity of results. The objective of the present study was to validate PCR as a diagnostic test for T. vivax trypanosomosis by means of determining the test sensitivity of different published specific primers with different sample preparations. Four different DNA extraction methods were used to test the sensitivity of PCR with four different primer sets. DNA was extracted directly from whole blood samples, blood dried on filter papers or blood dried on FTA cards. The results showed that the sensitivity of PCR with each primer set was highly dependant of the sample preparation and DNA extraction method. The highest sensitivities for all the primers tested were determined using DNA extracted from whole blood samples, while the lowest sensitivities were obtained when DNA was extracted from filter paper preparations. To conclude, the obtained results are discussed and a protocol for diagnosis and surveillance for T. vivax trypanosomosis is recommended.

Valid statistical inference methods for a case-control study with missing data.

PubMed

Tian, Guo-Liang; Zhang, Chi; Jiang, Xuejun

2018-04-01

The main objective of this paper is to derive the valid sampling distribution of the observed counts in a case-control study with missing data under the assumption of missing at random by employing the conditional sampling method and the mechanism augmentation method. The proposed sampling distribution, called the case-control sampling distribution, can be used to calculate the standard errors of the maximum likelihood estimates of parameters via the Fisher information matrix and to generate independent samples for constructing small-sample bootstrap confidence intervals. Theoretical comparisons of the new case-control sampling distribution with two existing sampling distributions exhibit a large difference. Simulations are conducted to investigate the influence of the three different sampling distributions on statistical inferences. One finding is that the conclusion by the Wald test for testing independency under the two existing sampling distributions could be completely different (even contradictory) from the Wald test for testing the equality of the success probabilities in control/case groups under the proposed distribution. A real cervical cancer data set is used to illustrate the proposed statistical methods.

Development and testing of the ‘Culture of Care Barometer’ (CoCB) in healthcare organisations: a mixed methods study

PubMed Central

Rafferty, Anne Marie; Philippou, Julia; Fitzpatrick, Joanne M; Pike, Geoff; Ball, Jane

2017-01-01

Objective Concerns about care quality have prompted calls to create workplace cultures conducive to high-quality, safe and compassionate care and to provide a supportive environment in which staff can operate effectively. How healthcare organisations assess their culture of care is an important first step in creating such cultures. This article reports on the development and validation of a tool, the Culture of Care Barometer, designed to assess perceptions of a caring culture among healthcare workers preliminary to culture change. Design/setting/participants An exploratory mixed methods study designed to develop and test the validity of a tool to measure ‘culture of care’ through focus groups and questionnaires. Questionnaire development was facilitated through: a literature review, experts generating items of interest and focus group discussions with healthcare staff across specialities, roles and seniority within three types of public healthcare organisations in the UK. The tool was designed to be multiprofessional and pilot tested with a sample of 467 nurses and healthcare support workers in acute care and then validated with a sample of 1698 staff working across acute, mental health and community services in England. Exploratory factor analysis was used to identify dimensions underlying the Barometer. Results Psychometric testing resulted in the development of a 30-item questionnaire linked to four domains with retained items loading to four factors: organisational values (α=0.93, valid n=1568, M=3.7), team support (α=0.93, valid n=1557, M=3.2), relationships with colleagues (α=0.84, valid n=1617, M=4.0) and job constraints (α=0.70, valid n=1616, M=3.3). Conclusions The study developed a valid and reliable instrument with which to gauge the different attributes of care culture perceived by healthcare staff with potential for organisational benchmarking. PMID:28821526

Development and testing of the 'Culture of Care Barometer' (CoCB) in healthcare organisations: a mixed methods study.

PubMed

Rafferty, Anne Marie; Philippou, Julia; Fitzpatrick, Joanne M; Pike, Geoff; Ball, Jane

2017-08-18

Concerns about care quality have prompted calls to create workplace cultures conducive to high-quality, safe and compassionate care and to provide a supportive environment in which staff can operate effectively. How healthcare organisations assess their culture of care is an important first step in creating such cultures. This article reports on the development and validation of a tool, the Culture of Care Barometer, designed to assess perceptions of a caring culture among healthcare workers preliminary to culture change. An exploratory mixed methods study designed to develop and test the validity of a tool to measure 'culture of care' through focus groups and questionnaires. Questionnaire development was facilitated through: a literature review, experts generating items of interest and focus group discussions with healthcare staff across specialities, roles and seniority within three types of public healthcare organisations in the UK. The tool was designed to be multiprofessional and pilot tested with a sample of 467 nurses and healthcare support workers in acute care and then validated with a sample of 1698 staff working across acute, mental health and community services in England. Exploratory factor analysis was used to identify dimensions underlying the Barometer. Psychometric testing resulted in the development of a 30-item questionnaire linked to four domains with retained items loading to four factors: organisational values (α=0.93, valid n=1568, M=3.7), team support (α=0.93, valid n=1557, M=3.2), relationships with colleagues (α=0.84, valid n=1617, M=4.0) and job constraints (α=0.70, valid n=1616, M=3.3). The study developed a valid and reliable instrument with which to gauge the different attributes of care culture perceived by healthcare staff with potential for organisational benchmarking. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Validation of powder X-ray diffraction following EN ISO/IEC 17025.

PubMed

Eckardt, Regina; Krupicka, Erik; Hofmeister, Wolfgang

2012-05-01

Powder X-ray diffraction (PXRD) is used widely in forensic science laboratories with the main focus of qualitative phase identification. Little is found in literature referring to the topic of validation of PXRD in the field of forensic sciences. According to EN ISO/IEC 17025, the method has to be tested for several parameters. Trueness, specificity, and selectivity of PXRD were tested using certified reference materials or a combination thereof. All three tested parameters showed the secure performance of the method. Sample preparation errors were simulated to evaluate the robustness of the method. These errors were either easily detected by the operator or nonsignificant for phase identification. In case of the detection limit, a statistical evaluation of the signal-to-noise ratio showed that a peak criterion of three sigma is inadequate and recommendations for a more realistic peak criterion are given. Finally, the results of an international proficiency test showed the secure performance of PXRD. © 2012 American Academy of Forensic Sciences.

Unsteady Aerodynamic Model Tuning for Precise Flutter Prediction

NASA Technical Reports Server (NTRS)

Pak, Chan-Gi

2011-01-01

A simple method for an unsteady aerodynamic model tuning is proposed in this study. This method is based on the direct modification of the aerodynamic influence coefficient matrices. The aerostructures test wing 2 flight-test data is used to demonstrate the proposed model tuning method. The flutter speed margin computed using only the test validated structural dynamic model can be improved using the additional unsteady aerodynamic model tuning, and then the flutter speed margin requirement of 15 % in military specifications can apply towards the test validated aeroelastic model. In this study, unsteady aerodynamic model tunings are performed at two time invariant flight conditions, at Mach numbers of 0.390 and 0.456. When the Mach number for the unsteady model tuning approaches to the measured fluttering Mach number, 0.502, at the flight altitude of 9,837 ft, the estimated flutter speed is approached to the measured flutter speed at this altitude. The minimum flutter speed difference between the estimated and measured flutter speed is -.14 %.

Unsteady Aerodynamic Model Tuning for Precise Flutter Prediction

NASA Technical Reports Server (NTRS)

Pak, Chan-gi

2011-01-01

A simple method for an unsteady aerodynamic model tuning is proposed in this study. This method is based on the direct modification of the aerodynamic influence coefficient matrices. The aerostructures test wing 2 flight-test data is used to demonstrate the proposed model tuning method. The flutter speed margin computed using only the test validated structural dynamic model can be improved using the additional unsteady aerodynamic model tuning, and then the flutter speed margin requirement of 15 percent in military specifications can apply towards the test validated aeroelastic model. In this study, unsteady aerodynamic model tunings are performed at two time invariant flight conditions, at Mach numbers of 0.390 and 0.456. When the Mach number for the unsteady aerodynamic model tuning approaches to the measured fluttering Mach number, 0.502, at the flight altitude of 9,837 ft, the estimated flutter speed is approached to the measured flutter speed at this altitude. The minimum flutter speed difference between the estimated and measured flutter speed is -0.14 percent.

Improving the Validity and Reliability of a Health Promotion Survey for Physical Therapists

PubMed Central

Stephens, Jaca L.; Lowman, John D.; Graham, Cecilia L.; Morris, David M.; Kohler, Connie L.; Waugh, Jonathan B.

2013-01-01

Purpose Physical therapists (PTs) have a unique opportunity to intervene in the area of health promotion. However, no instrument has been validated to measure PTs’ views on health promotion in physical therapy practice. The purpose of this study was to evaluate the content validity and test-retest reliability of a health promotion survey designed for PTs. Methods An expert panel of PTs assessed the content validity of “The Role of Health Promotion in Physical Therapy Survey” and provided suggestions for revision. Item content validity was assessed using the content validity ratio (CVR) as well as the modified kappa statistic. Therapists then participated in the test-retest reliability assessment of the revised health promotion survey, which was assessed using a weighted kappa statistic. Results Based on feedback from the expert panelists, significant revisions were made to the original survey. The expert panel reached at least a majority consensus agreement for all items in the revised survey and the survey-CVR improved from 0.44 to 0.66. Only one item on the revised survey had substantial test-retest agreement, with 55% of the items having moderate agreement and 43% poor agreement. Conclusions All items on the revised health promotion survey demonstrated at least fair validity, but few items had reasonable test-retest reliability. Further modifications should be made to strengthen the validity and improve the reliability of this survey. PMID:23754935

Dynamic measurement of speed of sound in n-Heptane by ultrasonics during fuel injections.

PubMed

Minnetti, Elisa; Pandarese, Giuseppe; Evangelisti, Piersavio; Verdugo, Francisco Rodriguez; Ungaro, Carmine; Bastari, Alessandro; Paone, Nicola

2017-11-01

The paper presents a technique to measure the speed of sound in fuels based on pulse-echo ultrasound. The method is applied inside the test chamber of a Zeuch-type instrument used for indirect measurement of the injection rate (Mexus). The paper outlines the pulse-echo method, considering probe installation, ultrasound beam propagation inside the test chamber, typical signals obtained, as well as different processing algorithms. The method is validated in static conditions by comparing the experimental results to the NIST database both for water and n-Heptane. The ultrasonic system is synchronized to the injector so that time resolved samples of speed of sound can be successfully acquired during a series of injections. Results at different operating conditions in n-Heptane are shown. An uncertainty analysis supports the analysis of results and allows to validate the method. Experimental results show that the speed of sound variation during an injection event is less than 1%, so the Mexus model assumption to consider it constant during the injection is valid. Copyright © 2017 Elsevier B.V. All rights reserved.

Translation of the Neck Disability Index and validation of the Greek version in a sample of neck pain patients

PubMed Central

Trouli, Marianna N; Vernon, Howard T; Kakavelakis, Kyriakos N; Antonopoulou, Maria D; Paganas, Aristofanis N; Lionis, Christos D

2008-01-01

Background Neck pain is a highly prevalent condition resulting in major disability. Standard scales for measuring disability in patients with neck pain have a pivotal role in research and clinical settings. The Neck Disability Index (NDI) is a valid and reliable tool, designed to measure disability in activities of daily living due to neck pain. The purpose of our study was the translation and validation of the NDI in a Greek primary care population with neck complaints. Methods The original version of the questionnaire was used. Based on international standards, the translation strategy comprised forward translations, reconciliation, backward translation and pre-testing steps. The validation procedure concerned the exploration of internal consistency (Cronbach alpha), test-retest reliability (Intraclass Correlation Coefficient, Bland and Altman method), construct validity (exploratory factor analysis) and responsiveness (Spearman correlation coefficient, Standard Error of Measurement and Minimal Detectable Change) of the questionnaire. Data quality was also assessed through completeness of data and floor/ceiling effects. Results The translation procedure resulted in the Greek modified version of the NDI. The latter was culturally adapted through the pre-testing phase. The validation procedure raised a large amount of missing data due to low applicability, which were assessed with two methods. Floor or ceiling effects were not observed. Cronbach alpha was calculated as 0.85, which was interpreted as good internal consistency. Intraclass correlation coefficient was found to be 0.93 (95% CI 0.84–0.97), which was considered as very good test-retest reliability. Factor analysis yielded one factor with Eigenvalue 4.48 explaining 44.77% of variance. The Spearman correlation coefficient (0.3; P = 0.02) revealed some relation between the change score in the NDI and Global Rating of Change (GROC). The SEM and MDC were calculated as 0.64 and 1.78 respectively. Conclusion The Greek version of the NDI measures disability in patients with neck pain in a reliable, valid and responsive manner. It is considered a useful tool for research and clinical settings in Greek Primary Health Care. PMID:18647393

Reliability and Validity of a New Method for Isometric Back Extensor Strength Evaluation Using A Hand-Held Dynamometer

PubMed Central

2017-01-01

Objective To investigate the reliability and validity of a new method for isometric back extensor strength measurement using a portable dynamometer. Methods A chair equipped with a small portable dynamometer was designed (Power Track II Commander Muscle Tester). A total of 15 men (mean age, 34.8±7.5 years) and 15 women (mean age, 33.1±5.5 years) with no current back problems or previous history of back surgery were recruited. Subjects were asked to push the back of the chair while seated, and their isometric back extensor strength was measured by the portable dynamometer. Test-retest reliability was assessed with intraclass correlation coefficient (ICC). For the validity assessment, isometric back extensor strength of all subjects was measured by a widely used physical performance evaluation instrument, BTE PrimusRS system. The limit of agreement (LoA) from the Bland-Altman plot was evaluated between two methods. Results The test-retest reliability was excellent (ICC=0.82; 95% confidence interval, 0.65–0.91). The Bland-Altman plots demonstrated acceptable agreement between the two methods: the lower 95% LoA was −63.1 N and the upper 95% LoA was 61.1 N. Conclusion This study shows that isometric back extensor strength measurement using a portable dynamometer has good reliability and validity. PMID:29201818

Reliability and validity of pendulum test measures of spasticity obtained with the Polhemus tracking system from patients with chronic stroke

PubMed Central

Bohannon, Richard W; Harrison, Steven; Kinsella-Shaw, Jeffrey

2009-01-01

Background Spasticity is a common impairment accompanying stroke. Spasticity of the quadriceps femoris muscle can be quantified using the pendulum test. The measurement properties of pendular kinematics captured using a magnetic tracking system has not been studied among patients who have experienced a stroke. Therefore, this study describes the test-retest reliability and known groups and convergent validity of the pendulum test measures obtained with the Polhemus tracking system. Methods Eight patients with chronic stroke underwent pendulum tests with their affected and unaffected lower limbs, with and without the addition of a 2.2 kg cuff weight at the ankle, using the Polhemus magnetic tracking system. Also measured bilaterally were knee resting angles, Ashworth scores (grades 0–4) of quadriceps femoris muscles, patellar tendon (knee jerk) reflexes (grades 0–4), and isometric knee extension force. Results Three measures obtained from pendular traces of the affected side were reliable (intraclass correlation coefficient ≥ .844). Known groups validity was confirmed by demonstration of a significant difference in the measurements between sides. Convergent validity was supported by correlations ≥ .57 between pendulum test measures and other measures reflective of spasticity. Conclusion Pendulum test measures obtained with the Polhemus tracking system from the affected side of patients with stroke have good test-retest reliability and both known groups and convergent validity. PMID:19642989

Using qualitative methods to improve questionnaires for Spanish speakers: assessing face validity of a food behavior checklist.

PubMed

Banna, Jinan C; Vera Becerra, Luz E; Kaiser, Lucia L; Townsend, Marilyn S

2010-01-01

Development of outcome measures relevant to health nutrition behaviors requires a rigorous process of testing and revision. Whereas researchers often report performance of quantitative data collection to assess questionnaire validity and reliability, qualitative testing procedures are often overlooked. This report outlines a procedure for assessing face validity of a Spanish-language dietary assessment tool. Reviewing the literature produced no rigorously validated Spanish-language food behavior assessment tools for the US Department of Agriculture's food assistance and education programs. In response to this need, this study evaluated the face validity of a Spanish-language food behavior checklist adapted from a 16-item English version of a food behavior checklist shown to be valid and reliable for limited-resource English speakers. The English version was translated using rigorous methods involving initial translation by one party and creation of five possible versions. Photos were modified based on client input and new photos were taken as necessary. A sample of low-income, Spanish-speaking women completed cognitive interviews (n=20). Spanish translation experts (n=7) fluent in both languages and familiar with both cultures made minor modifications but essentially approved client preferences. The resulting checklist generated a readability score of 93, indicating low reading difficulty. The Spanish-language checklist has adequate face validity in the target population and is ready for further validation using convergent measures. At the conclusion of testing, this instrument may be used to evaluate nutrition education interventions in California. These qualitative procedures provide a framework for designing evaluation tools for low-literate audiences participating in the US Department of Agriculture food assistance and education programs. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

Using Qualitative Methods to Improve Questionnaires for Spanish Speakers: Assessing Face Validity of a Food Behavior Checklist

PubMed Central

BANNA, JINAN C.; VERA BECERRA, LUZ E.; KAISER, LUCIA L.; TOWNSEND, MARILYN S.

2015-01-01

Development of outcome measures relevant to health nutrition behaviors requires a rigorous process of testing and revision. Whereas researchers often report performance of quantitative data collection to assess questionnaire validity and reliability, qualitative testing procedures are often overlooked. This report outlines a procedure for assessing face validity of a Spanish-language dietary assessment tool. Reviewing the literature produced no rigorously validated Spanish-language food behavior assessment tools for the US Department of Agriculture’s food assistance and education programs. In response to this need, this study evaluated the face validity of a Spanish-language food behavior checklist adapted from a 16-item English version of a food behavior checklist shown to be valid and reliable for limited-resource English speakers. The English version was translated using rigorous methods involving initial translation by one party and creation of five possible versions. Photos were modified based on client input and new photos were taken as necessary. A sample of low-income, Spanish-speaking women completed cognitive interviews (n=20). Spanish translation experts (n=7) fluent in both languages and familiar with both cultures made minor modifications but essentially approved client preferences. The resulting checklist generated a readability score of 93, indicating low reading difficulty. The Spanish-language checklist has adequate face validity in the target population and is ready for further validation using convergent measures. At the conclusion of testing, this instrument may be used to evaluate nutrition education interventions in California. These qualitative procedures provide a framework for designing evaluation tools for low-literate audiences participating in the US Department of Agriculture food assistance and education programs. PMID:20102831

Development and Validation of an Instrument to Assess the Implementation of Family-Centred Care in Traditional Open Bay Neonatal Intensive Care Units

ERIC Educational Resources Information Center

Al-Motlaq, Mohammad A.; Abuidhail, Jamila; Salameh, Taghreed; Awwad, Wesam

2017-01-01

Objective: To develop an instrument to study family-centred care (FCC) in traditional open bay Neonatal Intensive Care Units (NICUs). Methods: The development process involved constructing instrument's items, establishing content validity by an expert panel and testing the instrument for validity and reliability with a convenience sample of 25…

Assessing Reliability and Validity of the "GroPromo" Audit Tool for Evaluation of Grocery Store Marketing and Promotional Environments

ERIC Educational Resources Information Center

Kerr, Jacqueline; Sallis, James F.; Bromby, Erica; Glanz, Karen

2012-01-01

Objective: To evaluate reliability and validity of a new tool for assessing the placement and promotional environment in grocery stores. Methods: Trained observers used the "GroPromo" instrument in 40 stores to code the placement of 7 products in 9 locations within a store, along with other promotional characteristics. To test construct validity,…

The Predictive Validity of the Tilburg Frailty Indicator: Disability, Health Care Utilization, and Quality of Life in a Population at Risk

ERIC Educational Resources Information Center

Gobbens, Robbert J. J.; van Assen, Marcel A. L. M.; Luijkx, Katrien G.; Schols, Jos M. G. A.

2012-01-01

Purpose: To assess the predictive validity of frailty and its domains (physical, psychological, and social), as measured by the Tilburg Frailty Indicator (TFI), for the adverse outcomes disability, health care utilization, and quality of life. Design and Methods: The predictive validity of the TFI was tested in a representative sample of 484…

Concurrent validity of different functional and neuroproteomic pain assessment methods in the rat osteoarthritis monosodium iodoacetate (MIA) model.

PubMed

Otis, Colombe; Gervais, Julie; Guillot, Martin; Gervais, Julie-Anne; Gauvin, Dominique; Péthel, Catherine; Authier, Simon; Dansereau, Marc-André; Sarret, Philippe; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Beaudry, Francis; Troncy, Eric

2016-06-23

Lack of validity in osteoarthritis pain models and assessment methods is suspected. Our goal was to 1) assess the repeatability and reproducibility of measurement and the influence of environment, and acclimatization, to different pain assessment outcomes in normal rats, and 2) test the concurrent validity of the most reliable methods in relation to the expression of different spinal neuropeptides in a chemical model of osteoarthritic pain. Repeatability and inter-rater reliability of reflexive nociceptive mechanical thresholds, spontaneous static weight-bearing, treadmill, rotarod, and operant place escape/avoidance paradigm (PEAP) were assessed by the intraclass correlation coefficient (ICC). The most reliable acclimatization protocol was determined by comparing coefficients of variation. In a pilot comparative study, the sensitivity and responsiveness to treatment of the most reliable methods were tested in the monosodium iodoacetate (MIA) model over 21 days. Two MIA (2 mg) groups (including one lidocaine treatment group) and one sham group (0.9 % saline) received an intra-articular (50 μL) injection. No effect of environment (observer, inverted circadian cycle, or exercise) was observed; all tested methods except mechanical sensitivity (ICC <0.3), offered good repeatability (ICC ≥0.7). The most reliable acclimatization protocol included five assessments over two weeks. MIA-related osteoarthritic change in pain was demonstrated with static weight-bearing, punctate tactile allodynia evaluation, treadmill exercise and operant PEAP, the latter being the most responsive to analgesic intra-articular lidocaine. Substance P and calcitonin gene-related peptide were higher in MIA groups compared to naive (adjusted P (adj-P) = 0.016) or sham-treated (adj-P = 0.029) rats. Repeated post-MIA lidocaine injection resulted in 34 times lower downregulation for spinal substance P compared to MIA alone (adj-P = 0.029), with a concomitant increase of 17 % in time spent on the PEAP dark side (indicative of increased comfort). This study of normal rats and rats with pain established the most reliable and sensitive pain assessment methods and an optimized acclimatization protocol. Operant PEAP testing was more responsive to lidocaine analgesia than other tests used, while neuropeptide spinal concentration is an objective quantification method attractive to support and validate different centralized pain functional assessment methods.

An extended protocol for usability validation of medical devices: Research design and reference model.

PubMed

Schmettow, Martin; Schnittker, Raphaela; Schraagen, Jan Maarten

2017-05-01

This paper proposes and demonstrates an extended protocol for usability validation testing of medical devices. A review of currently used methods for the usability evaluation of medical devices revealed two main shortcomings. Firstly, the lack of methods to closely trace the interaction sequences and derive performance measures. Secondly, a prevailing focus on cross-sectional validation studies, ignoring the issues of learnability and training. The U.S. Federal Drug and Food Administration's recent proposal for a validation testing protocol for medical devices is then extended to address these shortcomings: (1) a novel process measure 'normative path deviations' is introduced that is useful for both quantitative and qualitative usability studies and (2) a longitudinal, completely within-subject study design is presented that assesses learnability, training effects and allows analysis of diversity of users. A reference regression model is introduced to analyze data from this and similar studies, drawing upon generalized linear mixed-effects models and a Bayesian estimation approach. The extended protocol is implemented and demonstrated in a study comparing a novel syringe infusion pump prototype to an existing design with a sample of 25 healthcare professionals. Strong performance differences between designs were observed with a variety of usability measures, as well as varying training-on-the-job effects. We discuss our findings with regard to validation testing guidelines, reflect on the extensions and discuss the perspectives they add to the validation process. Copyright © 2017 Elsevier Inc. All rights reserved.

Estimation of Sensory Analysis Cupping Test Arabica Coffee Using NIR Spectroscopy

NASA Astrophysics Data System (ADS)

Safrizal; Sutrisno; Lilik, P. E. N.; Ahmad, U.; Samsudin

2018-05-01

Flavors have become the most important coffee quality parameters now day, many coffee consuming countries require certain taste scores for the coffee to be ordered, the currently used cupping method of appraisal is the method designed by The Specialty Coffee Association Of America (SCAA), from several previous studies was found that Near-Infrared Spectroscopy (NIRS) can be used to detect chemical composition of certain materials including those associated with flavor so it is possible also to be applied to coffee powder. The aim of this research is to get correlation between NIRS spectrum with cupping scoring by tester, then look at the possibility of testing coffee taste sensors using NIRS spectrum. The coffee samples were taken from various places, altitudes and postharvest handling methods, then the samples were prepared following the SCAA protocol, for sensory analysis was done in two ways, with the expert tester and with the NIRS test. The calibration between both found that Without pretreatment using PLS get RMSE cross validation 6.14, using Multiplicative Scatter Correction spectra obtained RMSE cross validation 5.43, the best RMSE cross-validation was 1.73 achieved by de-trending correction, NIRS can be used to predict the score of cupping.

An Application of the Rasch Model to Computerized Adaptive Testing.

ERIC Educational Resources Information Center

Wisniewski, Dennis R.

Three questions concerning the Binary Search Method (BSM) of computerized adaptive testing were studied: (1) whether it provided a reliable and valid estimation of examinee ability; (2) its effect on examinee attitudes toward computerized adaptive testing and conventional paper-and-pencil testing; and (3) the relationship between item response…

76 FR 15945 - National Voluntary Laboratory Accreditation Program (NVLAP) Workshop for Laboratories Interested...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-22

... Accreditation Program (NVLAP) is considering establishing an accreditation program for laboratories that test... the general accreditation criteria referenced in Sections 4 and 5 of the NIST handbook 150 to the test... accreditation, test and measurement equipment, personnel requirements, validation of test methods, and reporting...

46 CFR 16.230 - Random testing requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... programs for the chemical testing for dangerous drugs on a random basis of crewmembers on inspected vessels... establish programs for the chemical testing for dangerous drugs on a random basis of crewmembers on... random drug testing shall be made by a scientifically valid method, such as a random number table or a...

46 CFR 16.230 - Random testing requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... programs for the chemical testing for dangerous drugs on a random basis of crewmembers on inspected vessels... establish programs for the chemical testing for dangerous drugs on a random basis of crewmembers on... random drug testing shall be made by a scientifically valid method, such as a random number table or a...

46 CFR 16.230 - Random testing requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... programs for the chemical testing for dangerous drugs on a random basis of crewmembers on inspected vessels... establish programs for the chemical testing for dangerous drugs on a random basis of crewmembers on... random drug testing shall be made by a scientifically valid method, such as a random number table or a...

46 CFR 16.230 - Random testing requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... programs for the chemical testing for dangerous drugs on a random basis of crewmembers on inspected vessels... establish programs for the chemical testing for dangerous drugs on a random basis of crewmembers on... random drug testing shall be made by a scientifically valid method, such as a random number table or a...

46 CFR 16.230 - Random testing requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... programs for the chemical testing for dangerous drugs on a random basis of crewmembers on inspected vessels... establish programs for the chemical testing for dangerous drugs on a random basis of crewmembers on... random drug testing shall be made by a scientifically valid method, such as a random number table or a...

A novel method to remotely measure food intake of free-living people in real-time

PubMed Central

Martin, Corby K.; Han, Hongmei; Coulon, Sandra M.; Allen, H. Raymond; Champagne, Catherine M.; Anton, Stephen D.

2008-01-01

The aim of this study was to report the first reliability and validity tests of the Remote Food Photography Method (RFPM), which consists of camera-enabled cell phones with data transfer capability. Participants take and transmit photographs of food selection and plate waste to researchers/clinicians for analysis. Following two pilot studies, adult participants (N=52, 20≤BMI≤35) were randomly assigned to the dine-in or take-out group. Energy intake (EI) was measured for three days. The dine-in group ate lunch and dinner in the laboratory. The take-out group ate lunch in the laboratory and dinner in free-living conditions (participants received a cooler with pre-weighed food that they returned the following morning). Energy intake was measured with the RFPM and by directly weighing foods. The RFPM was tested in laboratory and free-living conditions. Reliability was tested over three days and validity was tested by comparing directly weighed EI to EI estimated with the RFPM using Bland-Altman analysis. The RFPM produced reliable EI estimates over three days in laboratory (r=.62, p<.0001) and free-living (r=.68, p<.0001) conditions. Weighed EI correlated highly with EI estimated with the RFPM in laboratory and free-living conditions (r’s>.93, p<.0001). In two laboratory-based validity tests, the RFPM underestimated EI by -4.7% (p=.046) and -5.5% (p=.076). In free-living conditions, the RFPM underestimated EI by -6.6% (p=.017). Bias did not differ by body weight or age. The RFPM is a promising new method for accurately measuring the EI of free-living people. Error associated with the method is small compared to self-report methods. PMID:18616837

Crack propagation monitoring in a full-scale aircraft fatigue test based on guided wave-Gaussian mixture model

NASA Astrophysics Data System (ADS)

Qiu, Lei; Yuan, Shenfang; Bao, Qiao; Mei, Hanfei; Ren, Yuanqiang

2016-05-01

For aerospace application of structural health monitoring (SHM) technology, the problem of reliable damage monitoring under time-varying conditions must be addressed and the SHM technology has to be fully validated on real aircraft structures under realistic load conditions on ground before it can reach the status of flight test. In this paper, the guided wave (GW) based SHM method is applied to a full-scale aircraft fatigue test which is one of the most similar test status to the flight test. To deal with the time-varying problem, a GW-Gaussian mixture model (GW-GMM) is proposed. The probability characteristic of GW features, which is introduced by time-varying conditions is modeled by GW-GMM. The weak cumulative variation trend of the crack propagation, which is mixed in time-varying influence can be tracked by the GW-GMM migration during on-line damage monitoring process. A best match based Kullback-Leibler divergence is proposed to measure the GW-GMM migration degree to reveal the crack propagation. The method is validated in the full-scale aircraft fatigue test. The validation results indicate that the reliable crack propagation monitoring of the left landing gear spar and the right wing panel under realistic load conditions are achieved.

Initial Development and Validation of the BullyHARM: The Bullying, Harassment, and Aggression Receipt Measure.

PubMed

Hall, William J

2016-11-01

This article describes the development and preliminary validation of the Bullying, Harassment, and Aggression Receipt Measure (BullyHARM). The development of the BullyHARM involved a number of steps and methods, including a literature review, expert review, cognitive testing, readability testing, data collection from a large sample, reliability testing, and confirmatory factor analysis. A sample of 275 middle school students was used to examine the psychometric properties and factor structure of the BullyHARM, which consists of 22 items and 6 subscales: physical bullying, verbal bullying, social/relational bullying, cyber-bullying, property bullying, and sexual bullying. First-order and second-order factor models were evaluated. Results demonstrate that the first-order factor model had superior fit. Results of reliability testing indicate that the BullyHARM scale and subscales have very good internal consistency reliability. Findings indicate that the BullyHARM has good properties regarding content validation and respondent-related validation and is a promising instrument for measuring bullying victimization in school.

Initial Development and Validation of the BullyHARM: The Bullying, Harassment, and Aggression Receipt Measure

PubMed Central

Hall, William J.

2017-01-01

This article describes the development and preliminary validation of the Bullying, Harassment, and Aggression Receipt Measure (BullyHARM). The development of the BullyHARM involved a number of steps and methods, including a literature review, expert review, cognitive testing, readability testing, data collection from a large sample, reliability testing, and confirmatory factor analysis. A sample of 275 middle school students was used to examine the psychometric properties and factor structure of the BullyHARM, which consists of 22 items and 6 subscales: physical bullying, verbal bullying, social/relational bullying, cyber-bullying, property bullying, and sexual bullying. First-order and second-order factor models were evaluated. Results demonstrate that the first-order factor model had superior fit. Results of reliability testing indicate that the BullyHARM scale and subscales have very good internal consistency reliability. Findings indicate that the BullyHARM has good properties regarding content validation and respondent-related validation and is a promising instrument for measuring bullying victimization in school. PMID:28194041

Revalidation of game for teaching blood pressure auscultatory measurement: a pilot study.

PubMed

Bellan, Margarete Consorti; Alves, Vanessa Cortez; Neves, Mayza Luzia Dos Santos; Lamas, José Luiz Tatagiba

2017-01-01

To adapt a pre-existing educational game, making it specific to the teaching of blood pressure auscultatory measurement, and to apply this game in a pilot study. The original game cards were altered by the authors and submitted to content validation by six experts in the field. After redesigns, the game was applied to 30 subjects, who answered a questionnaire (pre-test and post-test) on auscultatory measurement. Data were analyzed descriptively and by the paired Student's t-test and paired Wilcoxon test. Throughout the content validation process, 17 of the 28 original cards were modified. Of these 17 cards, 13 obtained 80% agreement, and the rest were modified according to the judges' suggestions. The obtained grades significantly increased between pre- and the post-test. It was concluded that the reformulated game presented satisfactory evidence of content validity. Its use as a teaching-learning method was effective for this sample.

InstantLabs Listeria monocytogenes food safety kit. Performance tested method 051304.

PubMed

Sharma, Neil; Bambusch, Lauren; Le, Thu; Morey, Amit

2014-01-01

The InstantLabs Listeria monocytogenes Food Safety Kit was validated against the International Organization for Standardization (ISO) reference method 11290-1 for the detection of Listeria monocytogenes and other Listeria species. The matrixes (stainless steel, sealed concrete, ice cream, whole milk, cheddar cheese, raw shrimp, hot dogs, deli turkey, and lettuce) were inoculated with approximately 1 CFU/test portion of L. monocytogenes to generate fractional positives (5-15) in 20 inoculated samples. Enrichments were also fractionally inoculated with L. grayii for side-by-side testing of the Listeria Species Food Safety Kit. Stainless steel and sealed concrete samples were validated using 4 x 4" and 1 x 1 " test areas, respectively, and enriched in Buffered Listeria Enrichment Broth (BLEB) at 35 +/- 1degreesC for 22-28 h. All food samples were tested at 25 g and enriched in BLEB at 35 +/- 1 degreesC for 24-28 h. All samples were confirmed using the ISO reference method, regardless of initial screen result. The InstantLabs test method performed as well as or better than the reference method for the detection of L. monocytogenes on stainless steel and sealed concrete and in ice cream, whole milk, cheddar cheese, raw shrimp, hot dogs, deli turkey, and lettuce. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 50 L. monocytogenes serovars and 30 non-L. monocytogenes species examined. The method was shown to be robust when the enrichment times, volumes for DNA extraction, and heat block times were varied.

InstantLabs Listeria species food safety kit. Performance tested methods 041304.

PubMed

Sharma, Neil; Bambusch, Lauren; Le, Thu; Morey, Amit

2014-01-01

The InstantLabs Listeria Species Food SafetyKitwas validated against the International Organization for Standardization (ISO) reference method 11290-1 for the detection of Listeria monocytogenes and other Listeria species. The matrixes (stainless steel, sealed concrete, cheddar cheese, raw shrimp, and hot dogs) were inoculated with approximately 1 CFU/test portion of various Listeria species to generate fractional positives (5-15) in 20 inoculated samples. Enrichments were also fractionally inoculated with L. monocytogenes for side-by-side testing of the InstantLabs Listeria monocytogenes Food Safety Kit. Stainless steel and sealed concrete samples were validated using 4 x 4" and 1 x 1" test areas, respectively, and enriched in Buffered Listeria Enrichment Broth (BLEB) at 35 +/- 1 degrees C for 22-28 h. All food samples were tested at 25 g or 25 mL and enriched in BLEB at 35 +/- 1 degrees C for 24-28 h. All samples were confirmed using the ISO reference method, regardless of initial screen result. The InstantLabs test method performed as well as or better than the reference method for the detection of Listeria species on stainless steel, sealed concrete, cheddar cheese, raw shrimp, and hot dogs. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 80 Listeria species and 30 non-Listeria species examined. The method was shown to be robust when variations were introduced to the enrichment time, the volume for DNA extraction, and the heat block time (data not shown).

Best Practices in Stability Indicating Method Development and Validation for Non-clinical Dose Formulations.

PubMed

Henry, Teresa R; Penn, Lara D; Conerty, Jason R; Wright, Francesca E; Gorman, Gregory; Pack, Brian W

2016-11-01

Non-clinical dose formulations (also known as pre-clinical or GLP formulations) play a key role in early drug development. These formulations are used to introduce active pharmaceutical ingredients (APIs) into test organisms for both pharmacokinetic and toxicological studies. Since these studies are ultimately used to support dose and safety ranges in human studies, it is important to understand not only the concentration and PK/PD of the active ingredient but also to generate safety data for likely process impurities and degradation products of the active ingredient. As such, many in the industry have chosen to develop and validate methods which can accurately detect and quantify the active ingredient along with impurities and degradation products. Such methods often provide trendable results which are predictive of stability, thus leading to the name; stability indicating methods. This document provides an overview of best practices for those choosing to include development and validation of such methods as part of their non-clinical drug development program. This document is intended to support teams who are either new to stability indicating method development and validation or who are less familiar with the requirements of validation due to their position within the product development life cycle.

Measuring engagement in nurses: the psychometric properties of the Persian version of Utrecht Work Engagement Scale

PubMed Central

Torabinia, Mansour; Mahmoudi, Sara; Dolatshahi, Mojtaba; Abyaz, Mohamad Reza

2017-01-01

Background: Considering the overall tendency in psychology, researchers in the field of work and organizational psychology have become progressively interested in employees’ effective and optimistic experiments at work such as work engagement. This study was conducted to investigate 2 main purposes: assessing the psychometric properties of the Utrecht Work Engagement Scale, and finding any association between work engagement and burnout in nurses. Methods: The present methodological study was conducted in 2015 and included 248 females and 34 males with 6 months to 30 years of job experience. After the translation process, face and content validity were calculated by qualitative and quantitative methods. Moreover, content validation ratio, scale-level content validity index and item-level content validity index were measured for this scale. Construct validity was determined by factor analysis. Moreover, internal consistency and stability reliability were assessed. Factor analysis, test-retest, Cronbach’s alpha, and association analysis were used as statistical methods. Results: Face and content validity were acceptable. Exploratory factor analysis suggested a new 3- factor model. In this new model, some items from the construct model of the original version were dislocated with the same 17 items. The new model was confirmed by divergent Copenhagen Burnout Inventory as the Persian version of UWES. Internal consistency reliability for the total scale and the subscales was 0.76 to 0.89. Results from Pearson correlation test indicated a high degree of test-retest reliability (r = 0. 89). ICC was also 0.91. Engagement was negatively related to burnout and overtime per month, whereas it was positively related with age and job experiment. Conclusion: The Persian 3– factor model of Utrecht Work Engagement Scale is a valid and reliable instrument to measure work engagement in Iranian nurses as well as in other medical professionals. PMID:28955665

A NASA Perspective and Validation and Testing of Design Hardening for the Natural Space Radiation Environment (GOMAC Tech 03)

NASA Technical Reports Server (NTRS)

Day, John H. (Technical Monitor); LaBel, Kenneth A.; Howard, James W.; Carts, Martin A.; Seidleck, Christine

2003-01-01

With the dearth of dedicated radiation hardened foundries, new and novel techniques are being developed for hardening designs using non-dedicated foundry services. In this paper, we will discuss the implications of validating these methods for the natural space radiation environment issues: total ionizing dose (TID) and single event effects (SEE). Topics of discussion include: Types of tests that are required, Design coverage (i.e., design libraries: do they need validating for each application?) A new task within NASA to compare existing design. This latter task is a new effort in FY03 utilizing a 8051 microcontroller core from multiple design hardening developers as a test vehicle to evaluate each mitigative technique.

Alternative methods to determine headwater benefits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, Y.S.; Perlack, R.D.; Sale, M.J.

1997-11-10

In 1992, the Federal Energy Regulatory Commission (FERC) began using a Flow Duration Analysis (FDA) methodology to assess headwater benefits in river basins where use of the Headwater Benefits Energy Gains (HWBEG) model may not result in significant improvements in modeling accuracy. The purpose of this study is to validate the accuracy and appropriateness of the FDA method for determining energy gains in less complex basins. This report presents the results of Oak Ridge National Laboratory`s (ORNL`s) validation of the FDA method. The validation is based on a comparison of energy gains using the FDA method with energy gains calculatedmore » using the MWBEG model. Comparisons of energy gains are made on a daily and monthly basis for a complex river basin (the Alabama River Basin) and a basin that is considered relatively simple hydrologically (the Stanislaus River Basin). In addition to validating the FDA method, ORNL was asked to suggest refinements and improvements to the FDA method. Refinements and improvements to the FDA method were carried out using the James River Basin as a test case.« less

Cross-Cultural adaption, validity and reliability of a Hindi version of the Corah’s Dental Anxiety Scale

PubMed Central

Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha

2018-01-01

Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah’s Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach’s alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach’s alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study. PMID:29744307

Cross-Cultural adaption, validity and reliability of a Hindi version of the Corah's Dental Anxiety Scale.

PubMed

Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha

2018-01-01

Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah's Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach's alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach's alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study.

[A Simultaneous Determination Method with Acetonitrile-n-Hexane Partitioning and Solid-Phase Extraction for Pesticide Residues in Livestock and Marine Products by GC-MS].

PubMed

Yoshizaki, Mayuko; Kobayashi, Yukari; Shimizu, Masanori; Maruyama, Kouichi

2015-01-01

A simultaneous determination method was examined for 312 pesticides (including isomers) in muscle of livestock and marine products by GC-MS. The pesticide residues extracted from samples with acetone and n-hexane were purified by acetonitrile-n-hexane partitioning, and C18 and SAX/PSA solid-phase extraction without using GPC. Matrix components such as cholesterol were effectively removed. In recovery tests performed by this method using pork, beef, chicken and shrimp, 237-257 pesticides showed recoveries within the range of 70-120% in each sample. Validity was confirmed for 214 of the target pesticides by means of a validation test using pork. In comparison with the Japanese official method using GPC, the treatment time of samples and the quantity of solvent were reduced substantially.

Validated Test Method 5030C: Purge-and-Trap for Aqueous Samples

EPA Pesticide Factsheets

This method describes a purge-and-trap procedure for the analysis of volatile organic compoundsin aqueous samples & water miscible liquid samples. It also describes the analysis of high concentration soil and waste sample extracts prepared in Method 5035.

Sterility and Safety Validation for Transport Packaging of Organs and Tissues.

PubMed

Cobos, M; Trunzo, L; Vogt, M V; Romero, O; Anessi, C; Pachado, J; Ciávaro, M N; Horak, C; Bacqué, M C

2018-03-01

The bags used in the transport of organs and tissues must be sterile, nontoxic, pyrogen free, and must serve as a barrier throughout their useful life. The goal of this study was to show the sterility, safety, and functionality of the bags subjected to irradiation, through validated procedures and techniques. The selected sterilization method was the use of gamma radiation. The sterilization dose was determined based on validated standards for the sterilization of medical products, ISO 11137-2: 2013 and ISO/TS 13004: 2013, using the Verification Dose Maximum method on samples belonging to 3 manufacturing lots. The ISO 10993-5: 2009 standard was used in the cytotoxicity tests, by means of extracts test and quantitative technique of MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. The tests to determine the expiration date of the kit were performed by ASTM F1980, accelerated aging, and ASTM D3078 to evaluate hermeticity. The irradiation dose validated to reach the required sterility safety level was 22.5 kGy. The constituent materials and the sterilization method do not generated cellular toxicity, and the product was not modified during the simulated time of 5 years. Sterilization by irradiation is a method that leaves no residue, does not harm the properties of the material because it is conducted in cold, and as the sterilizing agent, the energy absorbed by the product is highly penetrating and can be treated in its final packaging, with no risk of postcontamination. It is for this reason that it is prioritized over other methods of sterilization. Copyright © 2017 Elsevier Inc. All rights reserved.

The Arthroscopic Surgical Skill Evaluation Tool (ASSET)

PubMed Central

Koehler, Ryan J.; Amsdell, Simon; Arendt, Elizabeth A; Bisson, Leslie J; Braman, Jonathan P; Butler, Aaron; Cosgarea, Andrew J; Harner, Christopher D; Garrett, William E; Olson, Tyson; Warme, Winston J.; Nicandri, Gregg T.

2014-01-01

Background Surgeries employing arthroscopic techniques are among the most commonly performed in orthopaedic clinical practice however, valid and reliable methods of assessing the arthroscopic skill of orthopaedic surgeons are lacking. Hypothesis The Arthroscopic Surgery Skill Evaluation Tool (ASSET) will demonstrate content validity, concurrent criterion-oriented validity, and reliability, when used to assess the technical ability of surgeons performing diagnostic knee arthroscopy on cadaveric specimens. Study Design Cross-sectional study; Level of evidence, 3 Methods Content validity was determined by a group of seven experts using a Delphi process. Intra-articular performance of a right and left diagnostic knee arthroscopy was recorded for twenty-eight residents and two sports medicine fellowship trained attending surgeons. Subject performance was assessed by two blinded raters using the ASSET. Concurrent criterion-oriented validity, inter-rater reliability, and test-retest reliability were evaluated. Results Content validity: The content development group identified 8 arthroscopic skill domains to evaluate using the ASSET. Concurrent criterion-oriented validity: Significant differences in total ASSET score (p<0.05) between novice, intermediate, and advanced experience groups were identified. Inter-rater reliability: The ASSET scores assigned by each rater were strongly correlated (r=0.91, p <0.01) and the intra-class correlation coefficient between raters for the total ASSET score was 0.90. Test-retest reliability: there was a significant correlation between ASSET scores for both procedures attempted by each individual (r = 0.79, p<0.01). Conclusion The ASSET appears to be a useful, valid, and reliable method for assessing surgeon performance of diagnostic knee arthroscopy in cadaveric specimens. Studies are ongoing to determine its generalizability to other procedures as well as to the live OR and other simulated environments. PMID:23548808

Concurrent and discriminant validity of the Star Excursion Balance Test for military personnel with lateral ankle sprain.

PubMed

Bastien, Maude; Moffet, Hélène; Bouyer, Laurent; Perron, Marc; Hébert, Luc J; Leblond, Jean

2014-02-01

The Star Excursion Balance Test (SEBT) has frequently been used to measure motor control and residual functional deficits at different stages of recovery from lateral ankle sprain (LAS) in various populations. However, the validity of the measure used to characterize performance--the maximal reach distance (MRD) measured by visual estimation--is still unknown. To evaluate the concurrent validity of the MRD in the SEBT estimated visually vs the MRD measured with a 3D motion-capture system and evaluate and compare the discriminant validity of 2 MRD-normalization methods (by height or by lower-limb length) in participants with or without LAS (n = 10 per group). There is a high concurrent validity and a good degree of accuracy between the visual estimation measurement and the MRD gold-standard measurement for both groups and under all conditions. The Cohen d ratios between groups and MANOVA products were higher when computed from MRD data normalized by height. The results support the concurrent validity of visual estimation of the MRD and the use of the SEBT to evaluate motor control. Moreover, normalization of MRD data by height appears to increase the discriminant validity of this test.

Validity and reliability of a scale to measure genital body image.

PubMed

Zielinski, Ruth E; Kane-Low, Lisa; Miller, Janis M; Sampselle, Carolyn

2012-01-01

Women's body image dissatisfaction extends to body parts usually hidden from view--their genitals. Ability to measure genital body image is limited by lack of valid and reliable questionnaires. We subjected a previously developed questionnaire, the Genital Self Image Scale (GSIS) to psychometric testing using a variety of methods. Five experts determined the content validity of the scale. Then using four participant groups, factor analysis was performed to determine construct validity and to identify factors. Further construct validity was established using the contrasting groups approach. Internal consistency and test-retest reliability was determined. Twenty one of 29 items were considered content valid. Two items were added based on expert suggestions. Factor analysis was undertaken resulting in four factors, identified as Genital Confidence, Appeal, Function, and Comfort. The revised scale (GSIS-20) included 20 items explaining 59.4% of the variance. Women indicating an interest in genital cosmetic surgery exhibited significantly lower scores on the GSIS-20 than those who did not. The final 20 item scale exhibited internal reliability across all sample groups as well as test-retest reliability. The GSIS-20 provides a measure of genital body image demonstrating reliability and validity across several populations of women.

Validity and reliability of the session-RPE method for quantifying training in Australian football: a comparison of the CR10 and CR100 scales.

PubMed

Scott, Tannath J; Black, Cameron R; Quinn, John; Coutts, Aaron J

2013-01-01

The purpose of this study was to examine and compare the criterion validity and test-retest reliability of the CR10 and CR100 rating of perceived exertion (RPE) scales for team sport athletes that undertake high-intensity, intermittent exercise. Twenty-one male Australian football (AF) players (age: 19.0 ± 1.8 years, body mass: 83.92 ± 7.88 kg) participated the first part (part A) of this study, which examined the construct validity of the session-RPE (sRPE) method for quantifying training load in AF. Ten male athletes (age: 16.1 ± 0.5 years) participated in the second part of the study (part B), which compared the test-retest reliability of the CR10 and CR100 RPE scales. In part A, the validity of the sRPE method was assessed by examining the relationships between sRPE, and objective measures of internal (i.e., heart rate) and external training load (i.e., distance traveled), collected from AF training sessions. Part B of the study assessed the reliability of sRPE through examining the test-retest reliability of sRPE during 3 different intensities of controlled intermittent running (10, 11.5, and 13 km·h(-1)). Results from part A demonstrated strong correlations for CR10- and CR100-derived sRPE with measures of internal training load (Banisters TRIMP and Edwards TRIMP) (CR10: r = 0.83 and 0.83, and CR100: r = 0.80 and 0.81, p < 0.05). Correlations between sRPE and external training load (distance, higher speed running and player load) for both the CR10 (r = 0.81, 0.71, and 0.83) and CR100 (r = 0.78, 0.69, and 0.80) were significant (p < 0.05). Results from part B demonstrated poor reliability for both the CR10 (31.9% CV) and CR100 (38.6% CV) RPE scales after short bouts of intermittent running. Collectively, these results suggest both CR10- and CR100-derived sRPE methods have good construct validity for assessing training load in AF. The poor levels of reliability revealed under field testing indicate that the sRPE method may not be sensible to detecting small changes in exercise intensity during brief intermittent running bouts. Despite this limitation, the sRPE remains a valid method to quantify training loads in high-intensity, intermittent team sport.

Evaluation of two selection tests for recruitment into radiology specialty training.

PubMed

Patterson, Fiona; Knight, Alec; McKnight, Liam; Booth, Thomas C

2016-07-11

This study evaluated whether two selection tests previously validated for primary care General Practice (GP) trainee selection could provide a valid shortlisting selection method for entry into specialty training for the secondary care specialty of radiology. We conducted a retrospective analysis of data from radiology applicants who also applied to UK GP specialty training or Core Medical Training. The psychometric properties of the two selection tests, a clinical problem solving (CPS) test and situational judgement test (SJT), were analysed to evaluate their reliability. Predictive validity of the tests was analysed by comparing them with the current radiology selection assessments, and the licensure examination results taken after the first stage of training (Fellowship of the Royal College of Radiologists (FRCR) Part 1). The internal reliability of the two selection tests in the radiology applicant sample was good (α ≥ 0.80). The average correlation with radiology shortlisting selection scores was r = 0.26 for the CPS (with p < 0.05 in 5 of 11 shortlisting centres), r = 0.15 for the SJT (with p < 0.05 in 2 of 11 shortlisting centres) and r = 0.25 (with p < 0.05 in 5 of 11 shortlisting centres) for the two tests combined. The CPS test scores significantly correlated with performance in both components of the FRCR Part 1 examinations (r = 0.5 anatomy; r = 0.4 physics; p < 0.05 for both). The SJT did not correlate with either component of the examination. The current CPS test may be an appropriate selection method for shortlisting in radiology but would benefit from further refinement for use in radiology to ensure that the test specification is relevant. The evidence on whether the SJT may be appropriate for shortlisting in radiology is limited. However, these results may be expected to some extent since the SJT is designed to measure non-academic attributes. Further validation work (e.g. with non-academic outcome variables) is required to evaluate whether an SJT will add value in recruitment for radiology specialty training and will further inform construct validity of SJTs as a selection methodology.

Hyper-X Engine Design and Ground Test Program

NASA Technical Reports Server (NTRS)

Voland, R. T.; Rock, K. E.; Huebner, L. D.; Witte, D. W.; Fischer, K. E.; McClinton, C. R.

1998-01-01

The Hyper-X Program, NASA's focused hypersonic technology program jointly run by NASA Langley and Dryden, is designed to move hypersonic, air-breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. The Hyper-X research vehicle will provide the first ever opportunity to obtain data on an airframe integrated supersonic combustion ramjet propulsion system in flight, providing the first flight validation of wind tunnel, numerical and analytical methods used for design of these vehicles. A substantial portion of the integrated vehicle/engine flowpath development, engine systems verification and validation and flight test risk reduction efforts are experimentally based, including vehicle aeropropulsive force and moment database generation for flight control law development, and integrated vehicle/engine performance validation. The Mach 7 engine flowpath development tests have been completed, and effort is now shifting to engine controls, systems and performance verification and validation tests, as well as, additional flight test risk reduction tests. The engine wind tunnel tests required for these efforts range from tests of partial width engines in both small and large scramjet test facilities, to tests of the full flight engine on a vehicle simulator and tests of a complete flight vehicle in the Langley 8-Ft. High Temperature Tunnel. These tests will begin in the summer of 1998 and continue through 1999. The first flight test is planned for early 2000.

Single-strain-gage force/stiffness buckling prediction techniques on a hat-stiffened panel

NASA Technical Reports Server (NTRS)

Hudson, Larry D.; Thompson, Randolph C.

1991-01-01

Predicting the buckling characteristics of a test panel is necessary to ensure panel integrity during a test program. A single-strain-gage buckling prediction method was developed on a hat-stiffened, monolithic titanium buckling panel. The method is an adaptation of the original force/stiffness method which requires back-to-back gages. The single-gage method was developed because the test panel did not have back-to-back gages. The method was used to predict buckling loads and temperatures under various heating and loading conditions. The results correlated well with a finite element buckling analysis. The single-gage force/stiffness method was a valid real-time and post-test buckling prediction technique.

Optimization and Validation of a Plaque Reduction Neutralization Test for the Detection of Neutralizing Antibodies to Four Serotypes of Dengue Virus Used in Support of Dengue Vaccine Development

PubMed Central

Timiryasova, Tatyana M.; Bonaparte, Matthew I.; Luo, Ping; Zedar, Rebecca; Hu, Branda T.; Hildreth, Stephen W.

2013-01-01

A dengue plaque reduction neutralization test (PRNT) to measure dengue serotype–specific neutralizing antibodies for all four virus serotypes was developed, optimized, and validated in accordance with guidelines for validation of bioanalytical test methods using human serum samples from dengue-infected persons and persons receiving a dengue vaccine candidate. Production and characterization of dengue challenge viruses used in the assay was standardized. Once virus stocks were characterized, the dengue PRNT50 for each of the four serotypes was optimized according to a factorial design of experiments approach for critical test parameters, including days of cell seeding before testing, percentage of overlay carboxymethylcellulose medium, and days of incubation post-infection to generate a robust assay. The PRNT50 was then validated and demonstrated to be suitable to detect and measure dengue serotype-specific neutralizing antibodies in human serum samples with acceptable intra-assay and inter-assay precision, accuracy/dilutability, specificity, and with a lower limit of quantitation of 10. PMID:23458954

Validation and Recommendation of Methods to Measure Biogas Production Potential of Animal Manure

PubMed Central

Pham, C. H.; Triolo, J. M.; Cu, T. T. T.; Pedersen, L.; Sommer, S. G.

2013-01-01

In developing countries, biogas energy production is seen as a technology that can provide clean energy in poor regions and reduce pollution caused by animal manure. Laboratories in these countries have little access to advanced gas measuring equipment, which may limit research aimed at improving local adapted biogas production. They may also be unable to produce valid estimates of an international standard that can be used for articles published in international peer-reviewed science journals. This study tested and validated methods for measuring total biogas and methane (CH4) production using batch fermentation and for characterizing the biomass. The biochemical methane potential (BMP) (CH4 NL kg−1 VS) of pig manure, cow manure and cellulose determined with the Moller and VDI methods was not significantly different in this test (p>0.05). The biodegradability using a ratio of BMP and theoretical BMP (TBMP) was slightly higher using the Hansen method, but differences were not significant. Degradation rate assessed by methane formation rate showed wide variation within the batch method tested. The first-order kinetics constant k for the cumulative methane production curve was highest when two animal manures were fermented using the VDI 4630 method, indicating that this method was able to reach steady conditions in a shorter time, reducing fermentation duration. In precision tests, the repeatability of the relative standard deviation (RSDr) for all batch methods was very low (4.8 to 8.1%), while the reproducibility of the relative standard deviation (RSDR) varied widely, from 7.3 to 19.8%. In determination of biomethane concentration, the values obtained using the liquid replacement method (LRM) were comparable to those obtained using gas chromatography (GC). This indicates that the LRM method could be used to determine biomethane concentration in biogas in laboratories with limited access to GC. PMID:25049861

Validation of 13C-acetic acid breath test by measuring effects of loperamide, morphine, mosapride, and itopride on gastric emptying in mice.

PubMed

Matsumoto, Kenjiro; Kimura, Hiroshi; Tashima, Kimihito; Uchida, Masayuki; Horie, Syunji

2008-10-01

Several methods are used to evaluate gastric motility in rodents, but they all have technical limitations. Recent technical developments enable a convenient method to evaluate gastric motility. The (13)C-acetic acid breath test in rodents is a non-invasive and repeatable method that can be used without physical restraints. The present study aimed to validate the (13)C-acetic acid breath test by measuring the effects of loperamide, morphine, mosapride, and itopride on gastric emptying in mice. Loperamide (1-10 mg/kg) and morphine (1.25-10 mg/kg) slowed gastric emptying and decreased the maximum concentration (C(max)) and area under the curve (AUC(90 min)) value in a dose-dependent manner. Mosapride (0.2-5 mg/kg) accelerated gastric emptying and increased C(max) value. Mosapride (20 mg/kg) did not accelerate gastric emptying on the (13)C-breath test. Itopride (30 mg/kg, per os) significantly accelerated gastric emptying compared with the vehicle group. In a comparison with the conventional phenol red test, there was a correlation between the C(max) value of breath test and gastric emptying (%) of phenol red tests in treatment with loperamide or mosapride. These results indicate that the (13)C-acetic acid breath test is an accurate, noninvasive, and simple method for monitoring gastric emptying in mice. This method is useful to assess the effect of drugs and gut function pharmacologically.

Psychometric properties of Persian version of the Sustained Auditory Attention Capacity Test in children with attention deficit-hyperactivity disorder.

PubMed

Soltanparast, Sanaz; Jafari, Zahra; Sameni, Seyed Jalal; Salehi, Masoud

2014-01-01

The purpose of the present study was to evaluate the psychometric properties (validity and reliability) of the Persian version of the Sustained Auditory Attention Capacity Test in children with attention deficit hyperactivity disorder. The Persian version of the Sustained Auditory Attention Capacity Test was constructed to assess sustained auditory attention using the method provided by Feniman and colleagues (2007). In this test, comments were provided to assess the child's attentional deficit by determining inattention and impulsiveness error, the total scores of the sustained auditory attention capacity test and attention span reduction index. In the present study for determining the validity and reliability of in both Rey Auditory Verbal Learning test and the Persian version of the Sustained Auditory Attention Capacity Test (SAACT), 46 normal children and 41 children with Attention Deficit Hyperactivity (ADHD), all right-handed and aged between 7 and 11 of both genders, were evaluated. In determining convergent validity, a negative significant correlation was found between the three parts of the Rey Auditory Verbal Learning test (first, fifth, and immediate recall) and all indicators of the SAACT except attention span reduction. By comparing the test scores between the normal and ADHD groups, discriminant validity analysis showed significant differences in all indicators of the test except for attention span reduction (p< 0.001). The Persian version of the Sustained Auditory Attention Capacity test has good validity and reliability, that matches other reliable tests, and it can be used for the identification of children with attention deficits and if they suspected to have Attention Deficit Hyperactivity Disorder.

Reconceptualising the external validity of discrete choice experiments.

PubMed

Lancsar, Emily; Swait, Joffre

2014-10-01

External validity is a crucial but under-researched topic when considering using discrete choice experiment (DCE) results to inform decision making in clinical, commercial or policy contexts. We present the theory and tests traditionally used to explore external validity that focus on a comparison of final outcomes and review how this traditional definition has been empirically tested in health economics and other sectors (such as transport, environment and marketing) in which DCE methods are applied. While an important component, we argue that the investigation of external validity should be much broader than a comparison of final outcomes. In doing so, we introduce a new and more comprehensive conceptualisation of external validity, closely linked to process validity, that moves us from the simple characterisation of a model as being or not being externally valid on the basis of predictive performance, to the concept that external validity should be an objective pursued from the initial conceptualisation and design of any DCE. We discuss how such a broader definition of external validity can be fruitfully used and suggest innovative ways in which it can be explored in practice.

Validation of an Arabic version of Fatigue Severity Scale

PubMed Central

Al-Sobayel, Hana I.; Al-Hugail, Hind A.; AlSaif, Ranyah M.; Albawardi, Nada M.; Alnahdi, Ali H.; Daif, Abdulkader M.; Al-Arfaj, Hussein F.

2016-01-01

Objectives: To develop and test the psychometric properties of an Arabic version of Fatigue Severity Scale (FSS-Ar) that can be used to measure fatigue in Arabic patients with disorders where fatigue is a major symptom. Methods: Forward and backward translations of FSS were undertaken to develop an Arabic version. The validity and reliability of the FSS-Ar was then tested on 28 patients with systemic lupus erythematosus (SLE), 24 patients with multiple sclerosis (MS), and 31 healthy subjects. Exploratory factor analysis and hypothesis testing methods were used to examine construct validity. The correlation between FSS-Ar and the vitality domain of the RAND 36-Item Health was examined to test construct validity. The study was conducted at the King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia between February and June 2012. Results: Using a score of ≥4.05 to define fatigue, 39 of 52 (75%) participants were fatigued compared with 10 out of 31 (32%) healthy participants. The correlation between the FSS-Ar and the vitality domain of the RAND-36 was acceptable (r = -0.46). Factor analysis showed that items of the FSS-Ar measured one underlying construct, namely, fatigue. Test-retest reliability and internal consistency of the FSS-Ar was acceptable (intraclass correlation coefficient model 2,1 = 0.80; Cronbach’s alpha = 0.84). Conclusion: The Arabic version of the FSS demonstrated acceptable psychometric properties and was able to differentiate between patients with SLE or MS, and healthy subjects. PMID:26739978

The Polygraph: Concept, Usage and Validity.

ERIC Educational Resources Information Center

Simpson, B. Allen

1986-01-01

Deals with the use of the "lie detector" or "polygraphic test" as a method of detecting deception in industries and law enforcement agencies. Explains what the polygraph is and how it operates. Presents a series of specific arguments for and against the validity of the instrument. Research appears to be inconclusive. (Author/ABB)

Reliability and Validity of the Evidence-Based Practice Confidence (EPIC) Scale

ERIC Educational Resources Information Center

Salbach, Nancy M.; Jaglal, Susan B.; Williams, Jack I.

2013-01-01

Introduction: The reliability, minimal detectable change (MDC), and construct validity of the evidence-based practice confidence (EPIC) scale were evaluated among physical therapists (PTs) in clinical practice. Methods: A longitudinal mail survey was conducted. Internal consistency and test-retest reliability were estimated using Cronbach's alpha…

Assessment of abdominal muscle function using the Biodex System-4. Validity and reliability in healthy volunteers and patients with giant ventral hernia.

PubMed

Gunnarsson, U; Johansson, M; Strigård, K

2011-08-01

The decrease in recurrence rates in ventral hernia surgery have led to a redirection of focus towards other important patient-related endpoints. One such endpoint is abdominal wall function. The aim of the present study was to evaluate the reliability and external validity of abdominal wall strength measurement using the Biodex System-4 with a back abdomen unit. Ten healthy volunteers and ten patients with ventral hernias exceeding 10 cm were recruited. Test-retest reliability, both with and without girdle, was evaluated by comparison of measurements at two test occasions 1 week apart. Reliability was calculated by the interclass correlation coefficients (ICC) method. Validity was evaluated by correlation with the well-established International Physical Activity Questionnaire (IPAQ) and a self-assessment of abdominal wall strength. One person in the healthy group was excluded after the first test due to neck problems following minor trauma. The reliability was excellent (>0.75), with ICC values between 0.92 and 0.97 for the different modalities tested. No differences were seen between testing with and without a girdle. Validity was also excellent both when calculated as correlation to self-assessment of abdominal wall strength, and to IPAQ, giving Kendall tau values of 0.51 and 0.47, respectively, and corresponding P values of 0.002 and 0.004. Measurement of abdominal muscle function using the Biodex System-4 is a reliable and valid method to assess this important patient-related endpoint. Further investigations will be made to explore the potential of this technique in the evaluation of the results of ventral hernia surgery, and to compare muscle function after different abdominal wall reconstruction techniques.

Walk a Mile in My Shoes: Stakeholder Accounts of Testing Experience with a Computer-Administered Test

ERIC Educational Resources Information Center

Fox, Janna; Cheng, Liying

2015-01-01

In keeping with the trend to elicit multiple stakeholder responses to operational tests as part of test validation, this exploratory mixed methods study examines test-taker accounts of an Internet-based (i.e., computer-administered) test in the high-stakes context of proficiency testing for university admission. In 2013, as language testing…

Experimental determination of the oral bioavailability and bioaccessibility of lead particles

PubMed Central

2012-01-01

In vivo estimations of Pb particle bioavailability are costly and variable, because of the nature of animal assays. The most feasible alternative for increasing the number of investigations carried out on Pb particle bioavailability is in vitro testing. This testing method requires calibration using in vivo data on an adapted animal model, so that the results will be valid for childhood exposure assessment. Also, the test results must be reproducible within and between laboratories. The Relative Bioaccessibility Leaching Procedure, which is calibrated with in vivo data on soils, presents the highest degree of validation and simplicity. This method could be applied to Pb particles, including those in paint and dust, and those in drinking water systems, which although relevant, have been poorly investigated up to now for childhood exposure assessment. PMID:23173867

Could situational judgement tests be used for selection into dental foundation training?

PubMed

Patterson, F; Ashworth, V; Mehra, S; Falcon, H

2012-07-13

To pilot and evaluate a machine-markable situational judgement test (SJT) designed to select candidates into UK dental foundation training. Single centre pilot study. UK postgraduate deanery in 2010. Seventy-four candidates attending interview for dental foundation training in Oxford and Wessex Deaneries volunteered to complete the situational judgement test. The situational judgement test was developed to assess relevant professional attributes for dentistry (for example, empathy and integrity) in a machine-markable format. Test content was developed by subject matter experts working with experienced psychometricians. Evaluation of psychometric properties of the pilot situational judgement test (for example, reliability, validity and fairness). Scores in the dental foundation training selection process (short-listing and interviews) were used to examine criterion-related validity. Candidates completed an evaluation questionnaire to examine candidate reactions and face validity of the new test. Forty-six candidates were female and 28 male; mean age was 23.5-years-old (range 22-32). Situational judgement test scores were normally distributed and the test showed good internal reliability when corrected for test length (α = 0.74). Situational judgement test scores positively correlated with the management, leadership and professionalism interview (N = 50; r = 0.43, p <0.01) but not with the clinical skills interview, providing initial evidence of criterion-related validity as the situational judgement test is designed to test non-cognitive professional attributes beyond clinical knowledge. Most candidates perceived the situational judgement test as relevant to dentistry, appropriate for their training level, and fair. This initial pilot study suggests that a situational judgement test is an appropriate and innovative method to measure professional attributes (eg empathy and integrity) for selection into foundation training. Further research will explore the long-term predictive validity of the situational judgement test once candidates have entered training.

Validation of Ion Chromatographic Method for Determination of Standard Inorganic Anions in Treated and Untreated Drinking Water

NASA Astrophysics Data System (ADS)

Ivanova, V.; Surleva, A.; Koleva, B.

2018-06-01

An ion chromatographic method for determination of fluoride, chloride, nitrate and sulphate in untreated and treated drinking waters was described. An automated 850 IC Professional, Metrohm system equipped with conductivity detector and Metrosep A Supp 7-250 (250 x 4 mm) column was used. The validation of the method was performed for simultaneous determination of all studied analytes and the results have showed that the validated method fits the requirements of the current water legislation. The main analytical characteristics were estimated for each of studied analytes: limits of detection, limits of quantification, working and linear ranges, repeatability and intermediate precision, recovery. The trueness of the method was estimated by analysis of certified reference material for soft drinking water. Recovery test was performed on spiked drinking water samples. An uncertainty was estimated. The method was applied for analysis of drinking waters before and after chlorination.

Approach to method development and validation in capillary electrophoresis for enantiomeric purity testing of active basic pharmaceutical ingredients.

PubMed

Sokoliess, Torsten; Köller, Gerhard

2005-06-01

A chiral capillary electrophoresis system allowing the determination of the enantiomeric purity of an investigational new drug was developed using a generic method development approach for basic analytes. The method was optimized in terms of type and concentration of both cyclodextrin (CD) and electrolyte, buffer pH, temperature, voltage, and rinsing procedure. Optimal chiral separation of the analyte was obtained using an electrolyte with 2.5% carboxymethyl-beta-CD in 25 mM NaH2PO4 (pH 4.0). Interchanging the inlet and outlet vials after each run improved the method's precision. To assure the method's suitability for the control of enantiomeric impurities in pharmaceutical quality control, its specificity, linearity, precision, accuracy, and robustness were validated according to the requirements of the International Conference on Harmonization. The usefulness of our generic method development approach for the validation of robustness was demonstrated.

Secondary Schools Principals and Their Job Satisfaction: A Test of Process Theories

ERIC Educational Resources Information Center

Maforah, Tsholofelo Paulinah

2015-01-01

The study aims to test the validity of process theories on the job satisfaction of previously disadvantaged Secondary School principals in the North West province. A mixed-method approach consisting of both quantitative and qualitative methods was used for the study. A questionnaire was administered during the quantitative phase with a sample that…

Testing the Self-Efficacy Questionnaire with Korean Children in Institutionalized Care

ERIC Educational Resources Information Center

Kim, Youngmi; Kim, Kyeongmo; Lee, Shinhye

2017-01-01

Purpose: We tested the reliability and validity of the Self-Efficacy Questionnaire for Children (SEQ-C) in a sample of children living in orphanages in South Korea. Methods: Our study sample consisted of 334 children aged 13-18 obtained using a convenience sampling method. We conducted a confirmatory factor analysis to identify the factor…

A Residual Mass Ballistic Testing Method to Compare Armor Materials or Components (Residual Mass Ballistic Testing Method)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benjamin Langhorst; Thomas M Lillo; Henry S Chu

2014-05-01

A statistics based ballistic test method is presented for use when comparing multiple groups of test articles of unknown relative ballistic perforation resistance. The method is intended to be more efficient than many traditional methods for research and development testing. To establish the validity of the method, it is employed in this study to compare test groups of known relative ballistic performance. Multiple groups of test articles were perforated using consistent projectiles and impact conditions. Test groups were made of rolled homogeneous armor (RHA) plates and differed in thickness. After perforation, each residual projectile was captured behind the target andmore » its mass was measured. The residual masses measured for each test group were analyzed to provide ballistic performance rankings with associated confidence levels. When compared to traditional V50 methods, the residual mass (RM) method was found to require fewer test events and be more tolerant of variations in impact conditions.« less

Assessing Discriminative Performance at External Validation of Clinical Prediction Models.

PubMed

Nieboer, Daan; van der Ploeg, Tjeerd; Steyerberg, Ewout W

2016-01-01

External validation studies are essential to study the generalizability of prediction models. Recently a permutation test, focusing on discrimination as quantified by the c-statistic, was proposed to judge whether a prediction model is transportable to a new setting. We aimed to evaluate this test and compare it to previously proposed procedures to judge any changes in c-statistic from development to external validation setting. We compared the use of the permutation test to the use of benchmark values of the c-statistic following from a previously proposed framework to judge transportability of a prediction model. In a simulation study we developed a prediction model with logistic regression on a development set and validated them in the validation set. We concentrated on two scenarios: 1) the case-mix was more heterogeneous and predictor effects were weaker in the validation set compared to the development set, and 2) the case-mix was less heterogeneous in the validation set and predictor effects were identical in the validation and development set. Furthermore we illustrated the methods in a case study using 15 datasets of patients suffering from traumatic brain injury. The permutation test indicated that the validation and development set were homogenous in scenario 1 (in almost all simulated samples) and heterogeneous in scenario 2 (in 17%-39% of simulated samples). Previously proposed benchmark values of the c-statistic and the standard deviation of the linear predictors correctly pointed at the more heterogeneous case-mix in scenario 1 and the less heterogeneous case-mix in scenario 2. The recently proposed permutation test may provide misleading results when externally validating prediction models in the presence of case-mix differences between the development and validation population. To correctly interpret the c-statistic found at external validation it is crucial to disentangle case-mix differences from incorrect regression coefficients.

Antenna reconfiguration verification and validation

NASA Technical Reports Server (NTRS)

Becker, Robert C. (Inventor); Meyers, David W. (Inventor); Muldoon, Kelly P. (Inventor); Carlson, Douglas R. (Inventor); Drexler, Jerome P. (Inventor)

2009-01-01

A method of testing the electrical functionality of an optically controlled switch in a reconfigurable antenna is provided. The method includes configuring one or more conductive paths between one or more feed points and one or more test point with switches in the reconfigurable antenna. Applying one or more test signals to the one or more feed points. Monitoring the one or more test points in response to the one or more test signals and determining the functionality of the switch based upon the monitoring of the one or more test points.

Hydrogen Infrastructure Testing and Research Facility | Hydrogen and Fuel

Science.gov Websites

stations, enabling NREL to validate current industry standards and methods for hydrogen fueling as well as the HITRF to: Develop, quantify performance of, and improve renewable hydrogen production methods

Development and Validation of a New Questionnaire Assessing Quality of Life in Adults with Hypopituitarism: Adult Hypopituitarism Questionnaire (AHQ)

PubMed Central

Ishii, Hitoshi; Shimatsu, Akira; Okimura, Yasuhiko; Tanaka, Toshiaki; Hizuka, Naomi; Kaji, Hidesuke; Hanew, Kunihiko; Oki, Yutaka; Yamashiro, Sayuri; Takano, Koji; Chihara, Kazuo

2012-01-01

Objective To develop and validate the Adult Hypopituitarism Questionnaire (AHQ) as a disease-specific, self-administered questionnaire for evaluation of quality of life (QOL) in adult patients with hypopituitarism. Methods We developed and validated this new questionnaire, using a standardized procedure which included item development, pilot-testing and psychometric validation. Of the patients who participated in psychometric validation, those whose clinical conditions were judged to be stable were asked to answer the survey questionnaire twice, in order to assess test-retest reliability. Results Content validity of the initial questionnaire was evaluated via two pilot tests. After these tests, we made minor revisions and finalized the initial version of the questionnaire. The questionnaire was constructed with two domains, one psycho-social and the other physical. For psychometric assessment, analyses were performed on the responses of 192 adult patients with various types of hypopituitarism. The intraclass correlations of the respective domains were 0.91 and 0.95, and the Cronbach’s alpha coefficients were 0.96 and 0.95, indicating adequate test-retest reliability and internal consistency for each domain. For known-group validity, patients with hypopituitarism due to hypothalamic disorder showed significantly lower scores in 11 out of 13 sub-domains compared to those who had hypopituitarism due to pituitary disorder. Regarding construct validity, the domain structure was found to be almost the same as that initially hypothesized. Exploratory factor analysis (n = 228) demonstrated that each domain consisted of six and seven sub-domains. Conclusion The AHQ showed good reliability and validity for evaluating QOL in adult patients with hypopituitarism. PMID:22984490

Reproducibility and validity of a semi-quantitative FFQ for trace elements.

PubMed

Lee, Yujin; Park, Kyong

2016-09-01

The aim of this study was to test the reproducibility and validity of a self-administered FFQ for the Trace Element Study of Korean Adults in the Yeungnam area (SELEN). Study subjects were recruited from the SELEN cohort selected from rural and urban areas in Yeungnam, Korea. A semi-quantitative FFQ with 146 items was developed considering the dietary characteristics of cohorts in the study area. In a validation study, seventeen men and forty-eight women aged 38-62 years completed 3-d dietary records (DR) and two FFQ over a 3-month period. The validity was examined with the FFQ and DR, and the reproducibility was estimated using partial correlation coefficients, the Bland-Altman method and cross-classification. There were no significant differences between the mean intakes of selected nutrients as estimated from FFQ1, FFQ2 and DR. The median correlation coefficients for all nutrients were 0·47 and 0·56 in the reproducibility and validity tests, respectively. Bland-Altman's index and cross-classification showed acceptable agreement between FFQ1 and FFQ2 and between FFQ2 and DR. Ultimately, 78 % of the subjects were classified into the same and adjacent quartiles for most nutrients. In addition, the weighted κ value indicated that the two methods agreed fairly. In conclusion, this newly developed FFQ was a suitable dietary assessment method for the SELEN cohort study.

Reliability and validity of the adolescent health profile-types.

PubMed

Riley, A W; Forrest, C B; Starfield, B; Green, B; Kang, M; Ensminger, M

1998-08-01

The purpose of this study was to demonstrate the preliminary reliability and validity of a set 13 profiles of adolescent health that describe distinct patterns of health and health service requirements on four domains of health. Reliability and validity were tested in four ethnically diverse population samples of urban and rural youths aged 11 to 17-years-old in public schools (N = 4,066). The reliability of the classification procedure and construct validity were examined in terms of the predicted and actual distributions of age, gender, race, socioeconomic status, and family type. School achievement, medical conditions, and the proportion of youths with a psychiatric disorder also were examined as tests of construct validity. The classification method was shown to produce consistent results across the four populations in terms of proportions of youths assigned with specific sociodemographic characteristics. Variations in health described by specific profiles showed expected relations to sociodemographic characteristics, family structure, school achievement, medical disorders, and psychiatric disorders. This taxonomy of health profile-types appears to effectively describe a set of patterns that characterize adolescent health. The profile-types provide a unique and practical method for identifying subgroups having distinct needs for health services, with potential utility for health policy and planning. Such integrative reporting methods are critical for more effective utilization of health status instruments in health resource planning and policy development.

Development of Flight-Test Performance Estimation Techniques for Small Unmanned Aerial Systems

NASA Astrophysics Data System (ADS)

McCrink, Matthew Henry

This dissertation provides a flight-testing framework for assessing the performance of fixed-wing, small-scale unmanned aerial systems (sUAS) by leveraging sub-system models of components unique to these vehicles. The development of the sub-system models, and their links to broader impacts on sUAS performance, is the key contribution of this work. The sub-system modeling and analysis focuses on the vehicle's propulsion, navigation and guidance, and airframe components. Quantification of the uncertainty in the vehicle's power available and control states is essential for assessing the validity of both the methods and results obtained from flight-tests. Therefore, detailed propulsion and navigation system analyses are presented to validate the flight testing methodology. Propulsion system analysis required the development of an analytic model of the propeller in order to predict the power available over a range of flight conditions. The model is based on the blade element momentum (BEM) method. Additional corrections are added to the basic model in order to capture the Reynolds-dependent scale effects unique to sUAS. The model was experimentally validated using a ground based testing apparatus. The BEM predictions and experimental analysis allow for a parameterized model relating the electrical power, measurable during flight, to the power available required for vehicle performance analysis. Navigation system details are presented with a specific focus on the sensors used for state estimation, and the resulting uncertainty in vehicle state. Uncertainty quantification is provided by detailed calibration techniques validated using quasi-static and hardware-in-the-loop (HIL) ground based testing. The HIL methods introduced use a soft real-time flight simulator to provide inertial quality data for assessing overall system performance. Using this tool, the uncertainty in vehicle state estimation based on a range of sensors, and vehicle operational environments is presented. The propulsion and navigation system models are used to evaluate flight-testing methods for evaluating fixed-wing sUAS performance. A brief airframe analysis is presented to provide a foundation for assessing the efficacy of the flight-test methods. The flight-testing presented in this work is focused on validating the aircraft drag polar, zero-lift drag coefficient, and span efficiency factor. Three methods are detailed and evaluated for estimating these design parameters. Specific focus is placed on the influence of propulsion and navigation system uncertainty on the resulting performance data. Performance estimates are used in conjunction with the propulsion model to estimate the impact sensor and measurement uncertainty on the endurance and range of a fixed-wing sUAS. Endurance and range results for a simplistic power available model are compared to the Reynolds-dependent model presented in this work. Additional parameter sensitivity analysis related to state estimation uncertainties encountered in flight-testing are presented. Results from these analyses indicate that the sub-system models introduced in this work are of first-order importance, on the order of 5-10% change in range and endurance, in assessing the performance of a fixed-wing sUAS.

Testing alternative ground water models using cross-validation and other methods

USGS Publications Warehouse

Foglia, L.; Mehl, S.W.; Hill, M.C.; Perona, P.; Burlando, P.

2007-01-01

Many methods can be used to test alternative ground water models. Of concern in this work are methods able to (1) rank alternative models (also called model discrimination) and (2) identify observations important to parameter estimates and predictions (equivalent to the purpose served by some types of sensitivity analysis). Some of the measures investigated are computationally efficient; others are computationally demanding. The latter are generally needed to account for model nonlinearity. The efficient model discrimination methods investigated include the information criteria: the corrected Akaike information criterion, Bayesian information criterion, and generalized cross-validation. The efficient sensitivity analysis measures used are dimensionless scaled sensitivity (DSS), composite scaled sensitivity, and parameter correlation coefficient (PCC); the other statistics are DFBETAS, Cook's D, and observation-prediction statistic. Acronyms are explained in the introduction. Cross-validation (CV) is a computationally intensive nonlinear method that is used for both model discrimination and sensitivity analysis. The methods are tested using up to five alternative parsimoniously constructed models of the ground water system of the Maggia Valley in southern Switzerland. The alternative models differ in their representation of hydraulic conductivity. A new method for graphically representing CV and sensitivity analysis results for complex models is presented and used to evaluate the utility of the efficient statistics. The results indicate that for model selection, the information criteria produce similar results at much smaller computational cost than CV. For identifying important observations, the only obviously inferior linear measure is DSS; the poor performance was expected because DSS does not include the effects of parameter correlation and PCC reveals large parameter correlations. ?? 2007 National Ground Water Association.

Multireader multicase reader studies with binary agreement data: simulation, analysis, validation, and sizing.

PubMed

Chen, Weijie; Wunderlich, Adam; Petrick, Nicholas; Gallas, Brandon D

2014-10-01

We treat multireader multicase (MRMC) reader studies for which a reader's diagnostic assessment is converted to binary agreement (1: agree with the truth state, 0: disagree with the truth state). We present a mathematical model for simulating binary MRMC data with a desired correlation structure across readers, cases, and two modalities, assuming the expected probability of agreement is equal for the two modalities ([Formula: see text]). This model can be used to validate the coverage probabilities of 95% confidence intervals (of [Formula: see text], [Formula: see text], or [Formula: see text] when [Formula: see text]), validate the type I error of a superiority hypothesis test, and size a noninferiority hypothesis test (which assumes [Formula: see text]). To illustrate the utility of our simulation model, we adapt the Obuchowski-Rockette-Hillis (ORH) method for the analysis of MRMC binary agreement data. Moreover, we use our simulation model to validate the ORH method for binary data and to illustrate sizing in a noninferiority setting. Our software package is publicly available on the Google code project hosting site for use in simulation, analysis, validation, and sizing of MRMC reader studies with binary agreement data.

Multireader multicase reader studies with binary agreement data: simulation, analysis, validation, and sizing

PubMed Central

Chen, Weijie; Wunderlich, Adam; Petrick, Nicholas; Gallas, Brandon D.

2014-01-01

Abstract. We treat multireader multicase (MRMC) reader studies for which a reader’s diagnostic assessment is converted to binary agreement (1: agree with the truth state, 0: disagree with the truth state). We present a mathematical model for simulating binary MRMC data with a desired correlation structure across readers, cases, and two modalities, assuming the expected probability of agreement is equal for the two modalities (P1=P2). This model can be used to validate the coverage probabilities of 95% confidence intervals (of P1, P2, or P1−P2 when P1−P2=0), validate the type I error of a superiority hypothesis test, and size a noninferiority hypothesis test (which assumes P1=P2). To illustrate the utility of our simulation model, we adapt the Obuchowski–Rockette–Hillis (ORH) method for the analysis of MRMC binary agreement data. Moreover, we use our simulation model to validate the ORH method for binary data and to illustrate sizing in a noninferiority setting. Our software package is publicly available on the Google code project hosting site for use in simulation, analysis, validation, and sizing of MRMC reader studies with binary agreement data. PMID:26158051

Uncertainty estimates of purity measurements based on current information: toward a "live validation" of purity methods.

PubMed

Apostol, Izydor; Kelner, Drew; Jiang, Xinzhao Grace; Huang, Gang; Wypych, Jette; Zhang, Xin; Gastwirt, Jessica; Chen, Kenneth; Fodor, Szilan; Hapuarachchi, Suminda; Meriage, Dave; Ye, Frank; Poppe, Leszek; Szpankowski, Wojciech

2012-12-01

To predict precision and other performance characteristics of chromatographic purity methods, which represent the most widely used form of analysis in the biopharmaceutical industry. We have conducted a comprehensive survey of purity methods, and show that all performance characteristics fall within narrow measurement ranges. This observation was used to develop a model called Uncertainty Based on Current Information (UBCI), which expresses these performance characteristics as a function of the signal and noise levels, hardware specifications, and software settings. We applied the UCBI model to assess the uncertainty of purity measurements, and compared the results to those from conventional qualification. We demonstrated that the UBCI model is suitable to dynamically assess method performance characteristics, based on information extracted from individual chromatograms. The model provides an opportunity for streamlining qualification and validation studies by implementing a "live validation" of test results utilizing UBCI as a concurrent assessment of measurement uncertainty. Therefore, UBCI can potentially mitigate the challenges associated with laborious conventional method validation and facilitates the introduction of more advanced analytical technologies during the method lifecycle.

[Validation of measurement methods and estimation of uncertainty of measurement of chemical agents in the air at workstations].

PubMed

Dobecki, Marek

2012-01-01

This paper reviews the requirements for measurement methods of chemical agents in the air at workstations. European standards, which have a status of Polish standards, comprise some requirements and information on sampling strategy, measuring techniques, type of samplers, sampling pumps and methods of occupational exposure evaluation at a given technological process. Measurement methods, including air sampling and analytical procedure in a laboratory, should be appropriately validated before intended use. In the validation process, selected methods are tested and budget of uncertainty is set up. The validation procedure that should be implemented in the laboratory together with suitable statistical tools and major components of uncertainity to be taken into consideration, were presented in this paper. Methods of quality control, including sampling and laboratory analyses were discussed. Relative expanded uncertainty for each measurement expressed as a percentage, should not exceed the limit of values set depending on the type of occupational exposure (short-term or long-term) and the magnitude of exposure to chemical agents in the work environment.

Renewable Energy Generation and Storage Models | Grid Modernization | NREL

Science.gov Websites

-the-loop testing Projects Generator, Plant, and Storage Modeling, Simulation, and Validation NREL power plants. Power Hardware-in-the-Loop Testing NREL researchers are developing software-and-hardware -combined simulation testing methods known as power hardware-in-the-loop testing. Power hardware in the loop

Validation of wet mount microscopy against Trichomonas culture among women of reproductive age group in Western province, Sri Lanka.

PubMed

Banneheke, H; Fernandopulle, R; Gunasekara, U; Barua, A; Fernando, N; Wickremasinghe, R

2015-06-01

Wet mount microscopy is the most commonly used diagnostic method for trichomoniasis in clinical diagnostic services all over the world including Sri Lanka due to its availability, simplicity and is relatively inexpensive. However, Trichomonas culture and PCR are the gold standard tests. Unfortunately, neither the culture nor PCR is available for the diagnosis of trichomoniasis in Sri Lanka. Thus, it is important to validate the wet mount microscopy as it is the only available diagnostic test and has not been validated to date in Sri Lanka. The objective was to evaluate the validity and reliability of wet mount microscopy against gold standard Trichomonas culture among clinic based population of reproductive age group women in Western province, Sri Lanka. Women attending hospital and institutional based clinics were enrolled. They were interviewed and high vaginal swabs were taken for laboratory diagnosis by culture and wet mount microscopy. There were 601 participants in the age group of 15-45 years. Wet mount microscopy showed 68% sensitivity, 100% specificity, 100% positive (PPV) and 98% negative predictive values (NPV) (P=0.001, kappa=0.803) respectively against the gold standard culture. The area under the ROC curve was 0.840. Sensitivity of wet mount microscopy is low. However it has high validity and reliability as a specific diagnostic test for trichomoniasis. If it is to be used among women of reproductive age group in Western province, Sri Lanka, a culture method could be adopted as a second test to confirm the negative wet mount for symptomatic patients.

Test-Retest Stability of the Task and Ego Orientation Questionnaire

ERIC Educational Resources Information Center

Lane, Andrew M.; Nevill, Alan M.; Bowes, Neal; Fox, Kenneth R.

2005-01-01

Establishing stability, defined as observing minimal measurement error in a test-retest assessment, is vital to validating psychometric tools. Correlational methods, such as Pearson product-moment, intraclass, and kappa are tests of association or consistency, whereas stability or reproducibility (regarded here as synonymous) assesses the…

A Novel Eye-Tracking Method to Assess Attention Allocation in Individuals with and without Aphasia Using a Dual-Task Paradigm

PubMed Central

Heuer, Sabine; Hallowell, Brooke

2015-01-01

Numerous authors report that people with aphasia have greater difficulty allocating attention than people without neurological disorders. Studying how attention deficits contribute to language deficits is important. However, existing methods for indexing attention allocation in people with aphasia pose serious methodological challenges. Eye-tracking methods have great potential to address such challenges. We developed and assessed the validity of a new dual-task method incorporating eye tracking to assess attention allocation. Twenty-six adults with aphasia and 33 control participants completed auditory sentence comprehension and visual search tasks. To test whether the new method validly indexes well-documented patterns in attention allocation, demands were manipulated by varying task complexity in single- and dual-task conditions. Differences in attention allocation were indexed via eye-tracking measures. For all participants significant increases in attention allocation demands were observed from single- to dual-task conditions and from simple to complex stimuli. Individuals with aphasia had greater difficulty allocating attention with greater task demands. Relationships between eye-tracking indices of comprehension during single and dual tasks and standardized testing were examined. Results support the validity of the novel eye-tracking method for assessing attention allocation in people with and without aphasia. Clinical and research implications are discussed. PMID:25913549

Development and validation of an HPLC–MS/MS method to determine clopidogrel in human plasma

PubMed Central

Liu, Gangyi; Dong, Chunxia; Shen, Weiwei; Lu, Xiaopei; Zhang, Mengqi; Gui, Yuzhou; Zhou, Qinyi; Yu, Chen

2015-01-01

A quantitative method for clopidogrel using online-SPE tandem LC–MS/MS was developed and fully validated according to the well-established FDA guidelines. The method achieves adequate sensitivity for pharmacokinetic studies, with lower limit of quantifications (LLOQs) as low as 10 pg/mL. Chromatographic separations were performed on reversed phase columns Kromasil Eternity-2.5-C18-UHPLC for both methods. Positive electrospray ionization in multiple reaction monitoring (MRM) mode was employed for signal detection and a deuterated analogue (clopidogrel-d4) was used as internal standard (IS). Adjustments in sample preparation, including introduction of an online-SPE system proved to be the most effective method to solve the analyte back-conversion in clinical samples. Pooled clinical samples (two levels) were prepared and successfully used as real-sample quality control (QC) in the validation of back-conversion testing under different conditions. The result showed that the real samples were stable in room temperature for 24 h. Linearity, precision, extraction recovery, matrix effect on spiked QC samples and stability tests on both spiked QCs and real sample QCs stored in different conditions met the acceptance criteria. This online-SPE method was successfully applied to a bioequivalence study of 75 mg single dose clopidogrel tablets in 48 healthy male subjects. PMID:26904399

Symptom validity testing in memory clinics: Hippocampal-memory associations and relevance for diagnosing mild cognitive impairment.

PubMed

Rienstra, Anne; Groot, Paul F C; Spaan, Pauline E J; Majoie, Charles B L M; Nederveen, Aart J; Walstra, Gerard J M; de Jonghe, Jos F M; van Gool, Willem A; Olabarriaga, Silvia D; Korkhov, Vladimir V; Schmand, Ben

2013-01-01

Patients with mild cognitive impairment (MCI) do not always convert to dementia. In such cases, abnormal neuropsychological test results may not validly reflect cognitive symptoms due to brain disease, and the usual brain-behavior relationships may be absent. This study examined symptom validity in a memory clinic sample and its effect on the associations between hippocampal volume and memory performance. Eleven of 170 consecutive patients (6.5%; 13% of patients younger than 65 years) referred to memory clinics showed noncredible performance on symptom validity tests (SVTs, viz. Word Memory Test and Test of Memory Malingering). They were compared to a demographically matched group (n = 57) selected from the remaining patients. Hippocampal volume, measured by an automated volumetric method (Freesurfer), was correlated with scores on six verbal memory tests. The median correlation was r = .49 in the matched group. However, the relation was absent (median r = -.11) in patients who failed SVTs. Memory clinic samples may include patients who show noncredible performance, which invalidates their MCI diagnosis. This underscores the importance of applying SVTs in evaluating patients with cognitive complaints that may signify a predementia stage, especially when these patients are relatively young.

Review of the Subliminal Psychodynamic Activation Method.

ERIC Educational Resources Information Center

Hoffman, Janice Sue

The subliminal psychodynamic activation method (SPA), used in testing psychoanalytic propositions, has been subject to recent criticisms regarding methodological weaknesses. A review of the literature relating to this method can be helpful in determining the validity of these criticisms and the potential usefulness of the SPA method in testing…

Some important considerations in the development of stress corrosion cracking test methods.

NASA Technical Reports Server (NTRS)

Wei, R. P.; Novak, S. R.; Williams, D. P.

1972-01-01

Discussion of some of the precaution needs the development of fracture-mechanics based test methods for studying stress corrosion cracking involves. Following a review of pertinent analytical fracture mechanics considerations and of basic test methods, the implications for test corrosion cracking studies of the time-to-failure determining kinetics of crack growth and life are examined. It is shown that the basic assumption of the linear-elastic fracture mechanics analyses must be clearly recognized and satisfied in experimentation and that the effects of incubation and nonsteady-state crack growth must also be properly taken into account in determining the crack growth kinetics, if valid data are to be obtained from fracture-mechanics based test methods.

Comparison of infrared and 3D digital image correlation techniques applied for mechanical testing of materials

NASA Astrophysics Data System (ADS)

Krstulović-Opara, Lovre; Surjak, Martin; Vesenjak, Matej; Tonković, Zdenko; Kodvanj, Janoš; Domazet, Željko

2015-11-01

To investigate the applicability of infrared thermography as a tool for acquiring dynamic yielding in metals, a comparison of infrared thermography with three dimensional digital image correlation has been made. Dynamical tension tests and three point bending tests of aluminum alloys have been performed to evaluate results obtained by IR thermography in order to detect capabilities and limits for these two methods. Both approaches detect pastification zone migrations during the yielding process. The results of the tension test and three point bending test proved the validity of the IR approach as a method for evaluating the dynamic yielding process when used on complex structures such as cellular porous materials. The stability of the yielding process in the three point bending test, as contrary to the fluctuation of the plastification front in the tension test, is of great importance for the validation of numerical constitutive models. The research proved strong performance, robustness and reliability of the IR approach when used to evaluate yielding during dynamic loading processes, while the 3D DIC method proved to be superior in the low velocity loading regimes. This research based on two basic tests, proved the conclusions and suggestions presented in our previous research on porous materials where middle wave infrared thermography was applied.

Patient and Societal Value Functions for the Testing Morbidities Index

PubMed Central

Swan, John Shannon; Kong, Chung Yin; Lee, Janie M.; Akinyemi, Omosalewa; Halpern, Elkan F.; Lee, Pablo; Vavinskiy, Sergey; Williams, Olubunmi; Zoltick, Emilie S.; Donelan, Karen

2013-01-01

Background We developed preference-based and summated scale scoring for the Testing Morbidities Index (TMI) classification, which addresses short-term effects on quality of life from diagnostic testing before, during and after a testing procedure. Methods The two TMI value functions utilize multiattribute value techniques; one is patient-based and the other has a societal perspective. 206 breast biopsy patients and 466 (societal) subjects informed the models. Due to a lack of standard short-term methods for this application, we utilized the visual analog scale (VAS). Waiting trade-off (WTO) tolls provided an additional option for linear transformation of the TMI. We randomized participants to one of three surveys: the first derived weights for generic testing morbidity attributes and levels of severity with the VAS; a second developed VAS values and WTO tolls for linear transformation of the TMI to a death-healthy scale; the third addressed initial validation in a specific test (breast biopsy). 188 patients and 425 community subjects participated in initial validation, comparing direct VAS and WTO values to the TMI. Alternative TMI scoring as a non-preference summated scale was included, given evidence of construct and content validity. Results The patient model can use an additive function, while the societal model is multiplicative. Direct VAS and the VAS-scaled TMI were correlated across modeling groups (r=0.45 to 0.62) and agreement was comparable to the value function validation of the Health Utilities Index 2. Mean Absolute Difference (MAD) calculations showed a range of 0.07–0.10 in patients and 0.11–0.17 in subjects. MAD for direct WTO tolls compared to the WTO-scaled TMI varied closely around one quality-adjusted life day. Conclusions The TMI shows initial promise in measuring short-term testing-related health states. PMID:23689044

Validation of a urine circulating cathodic antigen cassette test for detection of Schistosoma haematobiumin uMkhanyakude district of South Africa.

PubMed

Rubaba, O; Chimbari, M J; Soko, W; Manyangadze, T; Mukaratirwa, S

2018-06-01

Circulating cathodic antigen (CCA) tests for schistosomiasis are fast and less complicated allowing making them good candidates for routine qualitative screening for schistosomiasis at point of care. The urine-CCA has been evaluated for detection of S. mansoni with promising results. Its specificity and consistency in detecting S. haematobium infection in different endemic regions has been variable. This study validated a rapid urine-CCA cassette test for qualitative detection of S. haematobium infection in an S. haematobium endemic area with low S. mansoni prevalence. Microscopic examination for the standard urine filtration technique was used to validate the commercially available urine-CCA cassette test (rapid medical diagnostics ® ). The validation was done in a sample of primary school pupils (n = 420) aged 10-15 years in schools in the Jozini Municipality, KZN. There was a relationship between infection intensity and a positive urine-CCA test. Using the urine filtration method as the gold standard, the prevalence for S. haematobium was 40%, the accuracy of the CCA kit was 54.8%, sensitivity was 68.1% while the specificity was 45.8%. The positive predictive value was 45.82% while the negative predictive value was 68.05%. Both the urine filtration and the urine-CCA methods detected heavy (≥50 eggs/10 mL urine) and light infections at statistically significant levels. The overall accuracy, sensitivity and specificity of the urine-CCA cassette test were low. The urine-CCA cassette test performed much better for heavy infections than low infections (p < 0.05) implying that the kit may not be suitable for low endemic areas. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessment protocols of maximum oxygen consumption in young people with Down syndrome--a review.

PubMed

Seron, Bruna Barboza; Greguol, Márcia

2014-03-01

Maximum oxygen consumption is considered the gold standard measure of cardiorespiratory fitness. Young people with Down syndrome (DS) present low values of this indicator compared to their peers without disabilities and to young people with an intellectual disability but without DS. The use of reliable and valid assessment methods provides more reliable results for the diagnosis of cardiorespiratory fitness and the response of this variable to exercise. The aim of the present study was to review the literature on the assessment protocols used to measure maximum oxygen consumption in children and adolescents with Down syndrome giving emphasis to the protocols used, the validation process and their feasibility. The search was carried out in eight electronic databases--Scopus, Medline-Pubmed, Web of science, SportDiscus, Cinhal, Academic Search Premier, Scielo, and Lilacs. The inclusion criteria were: (a) articles which assessed VO2peak and/or VO2max (independent of the validation method), (b) samples composed of children and/or adolescents with Down syndrome, (c) participants of up to 20 years old, and (d) studies performed after 1990. Fifteen studies were selected and, of these, 11 measured the VO2peak using tests performed in a laboratory, 2 used field tests and the remaining 2 used both laboratory and field tests. The majority of the selected studies used maximal tests and conducted familiarization sessions. All the studies took into account the clinical conditions that could hamper testing or endanger the individuals. However, a large number of studies used tests which had not been specifically validated for the evaluated population. Finally, the search emphasized the small number of studies which use field tests to evaluate oxygen consumption. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cross-cultural adaptation and psychometric evaluation of oral health impact profile among school teacher community

PubMed Central

Vyas, Shaleen; Nagarajappa, Sandesh; Dasar, Pralhad L.; Mishra, Prashant

2018-01-01

AIM: To translate OHIP-14 into Hindi and test its psychometric properties among school teacher community. METHODS: The OHIP-14 was translated to OHIP-14-H using WHO recommended translation protocol. During pre-testing, an expert panel assessed content validity of the questionnaire. Face validity was assessed on a sample of 10 individuals. The OHIP-14-H was administered on a random sample of 170 primary school teachers. Internal consistency and test-retest reliability were assessed using Cronbach's alpha and Intra-class correlation coefficient (ICC) respectively, with 2 weeks interval. Predictive validity was tested by comparing OHIP-14-H scores with clinical parameters. The concurrent validity was assessed using self-reported oral health and discriminant validity was ascertained through negative association with sociodemographic variables. RESULTS: The mean OHIP-14-H score was 9.57 (S.D = 4.58). ICC and Cronbach's alpha for OHIP-14-H was 0.96 and 0.92 respectively. Concurrent validity using binomial regression model indicated that good (OR = 0.56, 95% CI = 0.55 – 4.47) and moderate (OR = 0.25, 95% CI = 0.17 – 1.87) OHIP-14-H scores were negative but significant risk indicators of poor self reported oral health (P < 0.009). Significant predictive validity was observed between OHIP-14-H scores and clinical parameters (P < 0.000). CONCLUSION: Translated and culturally adapted OHIP-14-H indicates good reliability and validity among primary school teachers. PMID:29417064

Statistical Validation of Surrogate Endpoints: Another Look at the Prentice Criterion and Other Criteria.

PubMed

Saraf, Sanatan; Mathew, Thomas; Roy, Anindya

2015-01-01

For the statistical validation of surrogate endpoints, an alternative formulation is proposed for testing Prentice's fourth criterion, under a bivariate normal model. In such a setup, the criterion involves inference concerning an appropriate regression parameter, and the criterion holds if the regression parameter is zero. Testing such a null hypothesis has been criticized in the literature since it can only be used to reject a poor surrogate, and not to validate a good surrogate. In order to circumvent this, an equivalence hypothesis is formulated for the regression parameter, namely the hypothesis that the parameter is equivalent to zero. Such an equivalence hypothesis is formulated as an alternative hypothesis, so that the surrogate endpoint is statistically validated when the null hypothesis is rejected. Confidence intervals for the regression parameter and tests for the equivalence hypothesis are proposed using bootstrap methods and small sample asymptotics, and their performances are numerically evaluated and recommendations are made. The choice of the equivalence margin is a regulatory issue that needs to be addressed. The proposed equivalence testing formulation is also adopted for other parameters that have been proposed in the literature on surrogate endpoint validation, namely, the relative effect and proportion explained.

The reliability and validity of fatigue measures during multiple-sprint work: an issue revisited.

PubMed

Glaister, Mark; Howatson, Glyn; Pattison, John R; McInnes, Gill

2008-09-01

The ability to repeatedly produce a high-power output or sprint speed is a key fitness component of most field and court sports. The aim of this study was to evaluate the validity and reliability of eight different approaches to quantify this parameter in tests of multiple-sprint performance. Ten physically active men completed two trials of each of two multiple-sprint running protocols with contrasting recovery periods. Protocol 1 consisted of 12 x 30-m sprints repeated every 35 seconds; protocol 2 consisted of 12 x 30-m sprints repeated every 65 seconds. All testing was performed in an indoor sports facility, and sprint times were recorded using twin-beam photocells. All but one of the formulae showed good construct validity, as evidenced by similar within-protocol fatigue scores. However, the assumptions on which many of the formulae were based, combined with poor or inconsistent test-retest reliability (coefficient of variation range: 0.8-145.7%; intraclass correlation coefficient range: 0.09-0.75), suggested many problems regarding logical validity. In line with previous research, the results support the percentage decrement calculation as the most valid and reliable method of quantifying fatigue in tests of multiple-sprint performance.

An Adaptation of the Original Fresno Test to Measure Evidence-Based Practice Competence in Pediatric Bedside Nurses.

PubMed

Laibhen-Parkes, Natasha; Kimble, Laura P; Melnyk, Bernadette Mazurek; Sudia, Tanya; Codone, Susan

2018-06-01

Instruments used to assess evidence-based practice (EBP) competence in nurses have been subjective, unreliable, or invalid. The Fresno test was identified as the only instrument to measure all the steps of EBP with supportive reliability and validity data. However, the items and psychometric properties of the original Fresno test are only relevant to measure EBP with medical residents. Therefore, the purpose of this paper is to describe the development of the adapted Fresno test for pediatric nurses, and provide preliminary validity and reliability data for its use with Bachelor of Science in Nursing-prepared pediatric bedside nurses. General adaptations were made to the original instrument's case studies, item content, wording, and format to meet the needs of a pediatric nursing sample. The scoring rubric was also modified to complement changes made to the instrument. Content and face validity, and intrarater reliability of the adapted Fresno test were assessed during a mixed-methods pilot study conducted from October to December 2013 with 29 Bachelor of Science in Nursing-prepared pediatric nurses. Validity data provided evidence for good content and face validity. Intrarater reliability estimates were high. The adapted Fresno test presented here appears to be a valid and reliable assessment of EBP competence in Bachelor of Science in Nursing-prepared pediatric nurses. However, further testing of this instrument is warranted using a larger sample of pediatric nurses in diverse settings. This instrument can be a starting point for evaluating the impact of EBP competence on patient outcomes. © 2018 Sigma Theta Tau International.

Automatic item generation implemented for measuring artistic judgment aptitude.

PubMed

Bezruczko, Nikolaus

2014-01-01

Automatic item generation (AIG) is a broad class of methods that are being developed to address psychometric issues arising from internet and computer-based testing. In general, issues emphasize efficiency, validity, and diagnostic usefulness of large scale mental testing. Rapid prominence of AIG methods and their implicit perspective on mental testing is bringing painful scrutiny to many sacred psychometric assumptions. This report reviews basic AIG ideas, then presents conceptual foundations, image model development, and operational application to artistic judgment aptitude testing.

Validity and reliability of Internet-based physiotherapy assessment for musculoskeletal disorders: a systematic review.

PubMed

Mani, Suresh; Sharma, Shobha; Omar, Baharudin; Paungmali, Aatit; Joseph, Leonard

2017-04-01

Purpose The purpose of this review is to systematically explore and summarise the validity and reliability of telerehabilitation (TR)-based physiotherapy assessment for musculoskeletal disorders. Method A comprehensive systematic literature review was conducted using a number of electronic databases: PubMed, EMBASE, PsycINFO, Cochrane Library and CINAHL, published between January 2000 and May 2015. The studies examined the validity, inter- and intra-rater reliabilities of TR-based physiotherapy assessment for musculoskeletal conditions were included. Two independent reviewers used the Quality Appraisal Tool for studies of diagnostic Reliability (QAREL) and the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool to assess the methodological quality of reliability and validity studies respectively. Results A total of 898 hits were achieved, of which 11 articles based on inclusion criteria were reviewed. Nine studies explored the concurrent validity, inter- and intra-rater reliabilities, while two studies examined only the concurrent validity. Reviewed studies were moderate to good in methodological quality. The physiotherapy assessments such as pain, swelling, range of motion, muscle strength, balance, gait and functional assessment demonstrated good concurrent validity. However, the reported concurrent validity of lumbar spine posture, special orthopaedic tests, neurodynamic tests and scar assessments ranged from low to moderate. Conclusion TR-based physiotherapy assessment was technically feasible with overall good concurrent validity and excellent reliability, except for lumbar spine posture, orthopaedic special tests, neurodynamic testa and scar assessment.

Extension and Validation of a Hybrid Particle-Finite Element Method for Hypervelocity Impact Simulation. Chapter 2

NASA Technical Reports Server (NTRS)

Fahrenthold, Eric P.; Shivarama, Ravishankar

2004-01-01

The hybrid particle-finite element method of Fahrenthold and Horban, developed for the simulation of hypervelocity impact problems, has been extended to include new formulations of the particle-element kinematics, additional constitutive models, and an improved numerical implementation. The extended formulation has been validated in three dimensional simulations of published impact experiments. The test cases demonstrate good agreement with experiment, good parallel speedup, and numerical convergence of the simulation results.

PESTICIDE ANALYTICAL METHODS TO SUPPORT DUPLICATE-DIET HUMAN EXPOSURE MEASUREMENTS

EPA Science Inventory

Historically, analytical methods for determination of pesticides in foods have been developed in support of regulatory programs and are specific to food items or food groups. Most of the available methods have been developed, tested and validated for relatively few analytes an...

Measurement of Harm Outcomes in Older Adults after Hospital Discharge: Reliability and Validity

PubMed Central

Douglas, Alison; Letts, Lori; Eva, Kevin; Richardson, Julie

2012-01-01

Objectives. Defining and validating a measure of safety contributes to further validation of clinical measures. The objective was to define and examine the psychometric properties of the outcome “incidents of harm.” Methods. The Incident of Harm Caregiver Questionnaire was administered to caregivers of older adults discharged from hospital by telephone. Caregivers completed daily logs for one month and medical charts were examined. Results. Test-retest reliability (n = 38) was high for the occurrence of an incident of harm (yes/no; kappa = 1.0) and the type of incident (agreement = 100%). Validation against daily logs found no disagreement regarding occurrence or types of incidents. Validation with medical charts found no disagreement regarding incident occurrence and disagreement in half regarding incident type. Discussion. The data support the Incident of Harm Caregiver Questionnaire as a reliable and valid estimation of incidents for this sample and are important to researchers as a method to measure safety when validating clinical measures. PMID:22649728

Validation and cross-cultural pilot testing of compliance with standard precautions scale: self-administered instrument for clinical nurses.

PubMed

Lam, Simon C

2014-05-01

To perform detailed psychometric testing of the compliance with standard precautions scale (CSPS) in measuring compliance with standard precautions of clinical nurses and to conduct cross-cultural pilot testing and assess the relevance of the CSPS on an international platform. A cross-sectional and correlational design with repeated measures. Nursing students from a local registered nurse training university, nurses from different hospitals in Hong Kong, and experts in an international conference. The psychometric properties of the CSPS were evaluated via internal consistency, 2-week and 3-month test-retest reliability, concurrent validation, and construct validation. The cross-cultural pilot testing and relevance check was examined by experts on infection control from various developed and developing regions. Among 453 participants, 193 were nursing students, 165 were enrolled nurses, and 95 were registered nurses. The results showed that the CSPS had satisfactory reliability (Cronbach α = 0.73; intraclass correlation coefficient, 0.79 for 2-week test-retest and 0.74 for 3-month test-retest) and validity (optimum correlation with criterion measure; r = 0.76, P < .001; satisfactory results on known-group method and hypothesis testing). A total of 19 experts from 16 countries assured that most of the CSPS findings were relevant and globally applicable. The CSPS demonstrated satisfactory results on the basis of the standard international criteria on psychometric testing, which ascertained the reliability and validity of this instrument in measuring the compliance of clinical nurses with standard precautions. The cross-cultural pilot testing further reinforced the instrument's relevance and applicability in most developed and developing regions.

Usefulness and limitations of various guinea-pig test methods in detecting human skin sensitizers-validation of guinea-pig tests for skin hypersensitivity.

PubMed

Marzulli, F; Maguire, H C

1982-02-01

Several guinea-pig predictive test methods were evaluated by comparison of results with those obtained with human predictive tests, using ten compounds that have been used in cosmetics. The method involves the statistical analysis of the frequency with which guinea-pig tests agree with the findings of tests in humans. In addition, the frequencies of false positive and false negative predictive findings are considered and statistically analysed. The results clearly demonstrate the superiority of adjuvant tests (complete Freund's adjuvant) in determining skin sensitizers and the overall superiority of the guinea-pig maximization test in providing results similar to those obtained by human testing. A procedure is suggested for utilizing adjuvant and non-adjuvant test methods for characterizing compounds as of weak, moderate or strong sensitizing potential.

Detection of Mycoplasma hyopneumoniae by polymerase chain reaction in swine presenting respiratory problems

PubMed Central

Yamaguti, M.; Muller, E.E.; Piffer, A.I.; Kich, J.D.; Klein, C.S.; Kuchiishi, S.S.

2008-01-01

Since Mycoplasma hyopneumoniae isolation in appropriate media is a difficult task and impractical for daily routine diagnostics, Nested-PCR (N-PCR) techniques are currently used to improve the direct diagnostic sensitivity of Swine Enzootic Pneumonia. In a first experiment, this paper describes a N-PCR technique optimization based on three variables: different sampling sites, sample transport media, and DNA extraction methods, using eight pigs. Based on the optimization results, a second experiment was conducted for testing validity using 40 animals. In conclusion, the obtained results of the N-PCR optimization and validation allow us to recommend this test as a routine monitoring diagnostic method for Mycoplasma hyopneumoniae infection in swine herds. PMID:24031248

Quantitative determination of additive Chlorantraniliprole in Abamectin preparation: Investigation of bootstrapping soft shrinkage approach by mid-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Yan, Hong; Song, Xiangzhong; Tian, Kuangda; Chen, Yilin; Xiong, Yanmei; Min, Shungeng

2018-02-01

A novel method, mid-infrared (MIR) spectroscopy, which enables the determination of Chlorantraniliprole in Abamectin within minutes, is proposed. We further evaluate the prediction ability of four wavelength selection methods, including bootstrapping soft shrinkage approach (BOSS), Monte Carlo uninformative variable elimination (MCUVE), genetic algorithm partial least squares (GA-PLS) and competitive adaptive reweighted sampling (CARS) respectively. The results showed that BOSS method obtained the lowest root mean squared error of cross validation (RMSECV) (0.0245) and root mean squared error of prediction (RMSEP) (0.0271), as well as the highest coefficient of determination of cross-validation (Qcv2) (0.9998) and the coefficient of determination of test set (Q2test) (0.9989), which demonstrated that the mid infrared spectroscopy can be used to detect Chlorantraniliprole in Abamectin conveniently. Meanwhile, a suitable wavelength selection method (BOSS) is essential to conducting a component spectral analysis.

Assessment of Hybrid High-Order methods on curved meshes and comparison with discontinuous Galerkin methods

NASA Astrophysics Data System (ADS)

Botti, Lorenzo; Di Pietro, Daniele A.

2018-10-01

We propose and validate a novel extension of Hybrid High-Order (HHO) methods to meshes featuring curved elements. HHO methods are based on discrete unknowns that are broken polynomials on the mesh and its skeleton. We propose here the use of physical frame polynomials over mesh elements and reference frame polynomials over mesh faces. With this choice, the degree of face unknowns must be suitably selected in order to recover on curved meshes the same convergence rates as on straight meshes. We provide an estimate of the optimal face polynomial degree depending on the element polynomial degree and on the so-called effective mapping order. The estimate is numerically validated through specifically crafted numerical tests. All test cases are conducted considering two- and three-dimensional pure diffusion problems, and include comparisons with discontinuous Galerkin discretizations. The extension to agglomerated meshes with curved boundaries is also considered.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grigg, Reid; McPherson, Brian; Lee, Rober

The Southwest Regional Partnership on Carbon Sequestration (SWP) one of seven regional partnerships sponsored by the U.S. Department of Energy (USDOE) carried out five field pilot tests in its Phase II Carbon Sequestration Demonstration effort, to validate the most promising sequestration technologies and infrastructure concepts, including three geologic pilot tests and two terrestrial pilot programs. This field testing demonstrated the efficacy of proposed sequestration technologies to reduce or offset greenhouse gas emissions in the region. Risk mitigation, optimization of monitoring, verification, and accounting (MVA) protocols, and effective outreach and communication were additional critical goals of these field validation tests. Themore » program included geologic pilot tests located in Utah, New Mexico, Texas, and a region-wide terrestrial analysis. Each geologic sequestration test site was intended to include injection of a minimum of ~75,000 tons/year CO{sub 2}, with minimum injection duration of one year. These pilots represent medium- scale validation tests in sinks that host capacity for possible larger-scale sequestration operations in the future. These validation tests also demonstrated a broad variety of carbon sink targets and multiple value-added benefits, including testing of enhanced oil recovery and sequestration, enhanced coalbed methane production and a geologic sequestration test combined with a local terrestrial sequestration pilot. A regional terrestrial sequestration demonstration was also carried out, with a focus on improved terrestrial MVA methods and reporting approaches specific for the Southwest region.« less

THE 6-MINUTE WALK TEST AND OTHER CLINICAL ENDPOINTS IN DUCHENNE MUSCULAR DYSTROPHY: RELIABILITY, CONCURRENT VALIDITY, AND MINIMAL CLINICALLY IMPORTANT DIFFERENCES FROM A MULTICENTER STUDY

PubMed Central

McDonald, Craig M; Henricson, Erik K; Abresch, R Ted; Florence, Julaine; Eagle, Michelle; Gappmaier, Eduard; Glanzman, Allan M; Spiegel, Robert; Barth, Jay; Elfring, Gary; Reha, Allen; Peltz, Stuart W

2013-01-01

Introduction: An international clinical trial enrolled 174 ambulatory males ≥5 years old with nonsense mutation Duchenne muscular dystrophy (nmDMD). Pretreatment data provide insight into reliability, concurrent validity, and minimal clinically important differences (MCIDs) of the 6-minute walk test (6MWT) and other endpoints. Methods: Screening and baseline evaluations included the 6-minute walk distance (6MWD), timed function tests (TFTs), quantitative strength by myometry, the PedsQL, heart rate–determined energy expenditure index, and other exploratory endpoints. Results: The 6MWT proved feasible and reliable in a multicenter context. Concurrent validity with other endpoints was excellent. The MCID for 6MWD was 28.5 and 31.7 meters based on 2 statistical distribution methods. Conclusions: The ratio of MCID to baseline mean is lower for 6MWD than for other endpoints. The 6MWD is an optimal primary endpoint for Duchenne muscular dystrophy (DMD) clinical trials that are focused therapeutically on preservation of ambulation and slowing of disease progression. Muscle Nerve 48: 357–368, 2013 PMID:23674289

New Testing Methods to Assess Technical Problem-Solving Ability.

ERIC Educational Resources Information Center

Hambleton, Ronald K.; And Others

Tests to assess problem-solving ability being provided for the Air Force are described, and some details on the development and validation of these computer-administered diagnostic achievement tests are discussed. Three measurement approaches were employed: (1) sequential problem solving; (2) context-free assessment of fundamental skills and…

How Should Colleges Treat Multiple Admissions Test Scores? ACT Working Paper 2017-4

ERIC Educational Resources Information Center

Mattern, Krista; Radunzel, Justine; Bertling, Maria; Ho, Andrew

2017-01-01

The percentage of students retaking college admissions tests is rising (Harmston & Crouse, 2016). Researchers and college admissions offices currently use a variety of methods for summarizing these multiple scores. Testing companies, interested in validity evidence like correlations with college first-year grade-point averages (FYGPA), often…

Tissue Preservation Assessment Preliminary Results

NASA Technical Reports Server (NTRS)

Globus, Ruth; Costes, Sylvain

2017-01-01

Pre-flight groundbased testing done to prepare for the first Rodent Research mission validation flight, RR1 (Choi et al, 2016 PlosOne). We purified RNA and measured RIN values to assess quality of the samples. For protein, we measured liver enzyme activities. We tested protocol and methods of preservation to date. Here we present an overview of results related to tissue preservation from the RR1 validation mission and a summary of findings to date from investigators who received RR1 teissues various Biospecimen Sharing Program.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundstrom, Blake; Chakraborty, Sudipta; Lauss, Georg

This paper presents a concise description of state-of-the-art real-time simulation-based testing methods and demonstrates how they can be used independently and/or in combination as an integrated development and validation approach for smart grid DERs and systems. A three-part case study demonstrating the application of this integrated approach at the different stages of development and validation of a system-integrated smart photovoltaic (PV) inverter is also presented. Laboratory testing results and perspectives from two international research laboratories are included in the case study.

Validity of three clinical performance assessments of internal medicine clerks.

PubMed

Hull, A L; Hodder, S; Berger, B; Ginsberg, D; Lindheim, N; Quan, J; Kleinhenz, M E

1995-06-01

To analyze the construct validity of three methods to assess the clinical performances of internal medicine clerks. A multitrait-multimethod (MTMM) study was conducted at the Case Western Reserve University School of Medicine to determine the convergent and divergent validity of a clinical evaluation form (CEF) completed by faculty and residents, an objective structured clinical examination (OSCE), and the medicine subject test of the National Board of Medical Examiners. Three traits were involved in the analysis: clinical skills, knowledge, and personal characteristics. A correlation matrix was computed for 410 third-year students who completed the clerkship between August 1988 and July 1991. There was a significant (p < .01) convergence of the four correlations that assessed the same traits by using different methods. However, the four convergent correlations were of moderate magnitude (ranging from .29 to .47). Divergent validity was assessed by comparing the magnitudes of the convergence correlations with the magnitudes of correlations among unrelated assessments (i.e., different traits by different methods). Seven of nine possible coefficients were smaller than the convergent coefficients, suggesting evidence of divergent validity. A significant CEF method effect was identified. There was convergent validity and some evidence of divergent validity with a significant method effect. The findings were similar for correlations corrected for attenuation. Four conclusions were reached: (1) the reliability of the OSCE must be improved, (2) the CEF ratings must be redesigned to further discriminate among the specific traits assessed, (3) additional methods to assess personal characteristics must be instituted, and (4) several assessment methods should be used to evaluate individual student performances.

The Politics and Statistics of Value-Added Modeling for Accountability of Teacher Preparation Programs

ERIC Educational Resources Information Center

Lincove, Jane Arnold; Osborne, Cynthia; Dillon, Amanda; Mills, Nicholas

2014-01-01

Despite questions about validity and reliability, the use of value-added estimation methods has moved beyond academic research into state accountability systems for teachers, schools, and teacher preparation programs (TPPs). Prior studies of value-added measurement for TPPs test the validity of researcher-designed models and find that measuring…

An Examination of Construct Validity for the EARLI Numeracy Skill Measures

ERIC Educational Resources Information Center

Cheng, Weiyi; Lei, Pui-Wa; DiPerna, James C.

2017-01-01

The purpose of the current study was to examine dimensionality and concurrent validity evidence of the EARLI numeracy measures (DiPerna, Morgan, & Lei, 2007), which were developed to assess key skills such as number identification, counting, and basic arithmetic. Two methods (NOHARM with approximate chi-square test and DIMTEST with DETECT…

40 CFR 1054.505 - How do I test engines?

Code of Federal Regulations, 2010 CFR

2010-07-01

... following methods for confirming torque values for nonhandheld engines: (i) Calculate torque-related cycle... is valid. (ii) Evaluate each mode separately to validate the duty cycle. All torque feedback values recorded during non-idle sampling periods must be within ±2 percent of the reference value or within ±0.27...

Validating Cognitive Models of Task Performance in Algebra on the SAT®. Research Report No. 2009-3

ERIC Educational Resources Information Center

Gierl, Mark J.; Leighton, Jacqueline P.; Wang, Changjiang; Zhou, Jiawen; Gokiert, Rebecca; Tan, Adele

2009-01-01

The purpose of the study is to present research focused on validating the four algebra cognitive models in Gierl, Wang, et al., using student response data collected with protocol analysis methods to evaluate the knowledge structures and processing skills used by a sample of SAT test takers.

Seeking a Valid Gold Standard for an Innovative, Dialect-Neutral Language Test

ERIC Educational Resources Information Center

Pearson, Barbara Zurer; Jackson, Janice E.; Wu, Haotian

2014-01-01

Purpose: In this study, the authors explored alternative gold standards to validate an innovative, dialect-neutral language assessment. Method: Participants were 78 African American children, ages 5;0 (years;months) to 6;11. Twenty participants had previously been identified as having language impairment. The Diagnostic Evaluation of Language…

Measuring Recognition Performance Using Computer-Based and Paper-Based Methods.

ERIC Educational Resources Information Center

Federico, Pat-Anthony

1991-01-01

Using a within-subjects design, computer-based and paper-based tests of aircraft silhouette recognition were administered to 83 male naval pilots and flight officers to determine the relative reliabilities and validities of 2 measurement modes. Relative reliabilities and validities of the two modes were contingent on the multivariate measurement…

Stages of Psychometric Measure Development: The Example of the Generalized Expertise Measure (GEM)

ERIC Educational Resources Information Center

Germain, Marie-Line

2006-01-01

This paper chronicles the steps, methods, and presents hypothetical results of quantitative and qualitative studies being conducted to develop a Generalized Expertise Measure (GEM). Per Hinkin (1995), the stages of scale development are domain and item generation, content expert validation, and pilot test. Content/face validity and internal…

Validation of the theoretical domains framework for use in behaviour change and implementation research

PubMed Central

2012-01-01

Background An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Methods Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. Results There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): ‘Knowledge’, ‘Skills’, ‘Social/Professional Role and Identity’, ‘Beliefs about Capabilities’, ‘Optimism’, ‘Beliefs about Consequences’, ‘Reinforcement’, ‘Intentions’, ‘Goals’, ‘Memory, Attention and Decision Processes’, ‘Environmental Context and Resources’, ‘Social Influences’, ‘Emotions’, and ‘Behavioural Regulation’. Conclusions The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development. PMID:22530986

Applied Chaos Level Test for Validation of Signal Conditions Underlying Optimal Performance of Voice Classification Methods

ERIC Educational Resources Information Center

Liu, Boquan; Polce, Evan; Sprott, Julien C.; Jiang, Jack J.

2018-01-01

Purpose: The purpose of this study is to introduce a chaos level test to evaluate linear and nonlinear voice type classification method performances under varying signal chaos conditions without subjective impression. Study Design: Voice signals were constructed with differing degrees of noise to model signal chaos. Within each noise power, 100…

Fluorescent adduct formation with terbium: a novel strategy for transferrin glycoform identification in human body fluids and carbohydrate-deficient transferrin HPLC method validation.

PubMed

Sorio, Daniela; De Palo, Elio Franco; Bertaso, Anna; Bortolotti, Federica; Tagliaro, Franco

2017-02-01

This paper puts forward a new method for the transferrin (Tf) glycoform analysis in body fluids that involves the formation of a transferrin-terbium fluorescent adduct (TfFluo). The key idea is to validate the analytical procedure for carbohydrate-deficient transferrin (CDT), a traditional biochemical serum marker to identify chronic alcohol abuse. Terbium added to a human body-fluid sample produced TfFluo. Anion exchange HPLC technique, with fluorescence detection (λ exc 298 nm and λ em 550 nm), permitted clear separation and identification of Tf glycoform peaks without any interfering signals, allowing selective Tf sialoforms analysis in human serum and body fluids (cadaveric blood, cerebrospinal fluid, and dried blood spots) hampered for routine test. Serum samples (n = 78) were analyzed by both traditional absorbance (Abs) and fluorescence (Fl) HPLC methods and CDT% levels demonstrated a significant correlation (p < 0.001 Pearson). Intra- and inter-runs CV% was 3.1 and 4.6%, respectively. The cut-off of 1.9 CDT%, related to the HPLC Abs proposed as the reference method, by interpolation in the correlation curve with the present method demonstrated a 1.3 CDT% cut-off. Method comparison by Passing-Bablok and Bland-Altman tests demonstrated Fl versus Abs agreement. In conclusion, the novel method is a reliable test for CDT% analysis and provides a substantial analytical improvement offering important advantages in terms of types of body fluid analysis. Its sensitivity and absence of interferences extend clinical applications being reliable for CDT assay on body fluids usually not suitable for routine test. Graphical Abstract The formation of a transferrin-terbium fluorescent adduct can be used to analyze the transferrin glycoforms. The HPLC method for carbohydrate-deficient transferrin (CDT%) measurement was validated and employed to determine the levels in different body fluids.

A new alternative method for testing skin irritation using a human skin model: a pilot study.

PubMed

Miles, A; Berthet, A; Hopf, N B; Gilliet, M; Raffoul, W; Vernez, D; Spring, P

2014-03-01

Studies assessing skin irritation to chemicals have traditionally used laboratory animals; however, such methods are questionable regarding their relevance for humans. New in vitro methods have been validated, such as the reconstructed human epidermis (RHE) model (Episkin®, Epiderm®). The comparison (accuracy) with in vivo results such as the 4-h human patch test (HPT) is 76% at best (Epiderm®). There is a need to develop an in vitro method that better simulates the anatomo-pathological changes encountered in vivo. To develop an in vitro method to determine skin irritation using human viable skin through histopathology, and compare the results of 4 tested substances to the main in vitro methods and in vivo animal method (Draize test). Human skin removed during surgery was dermatomed and mounted on an in vitro flow-through diffusion cell system. Ten chemicals with known non-irritant (heptylbutyrate, hexylsalicylate, butylmethacrylate, isoproturon, bentazon, DEHP and methylisothiazolinone (MI)) and irritant properties (folpet, 1-bromohexane and methylchloroisothiazolinone (MCI/MI)), a negative control (sodiumchloride) and a positive control (sodiumlaurylsulphate) were applied. The skin was exposed at least for 4h. Histopathology was performed to investigate irritation signs (spongiosis, necrosis, vacuolization). We obtained 100% accuracy with the HPT model; 75% with the RHE models and 50% with the Draize test for 4 tested substances. The coefficients of variation (CV) between our three test batches were <0.1, showing good reproducibility. Furthermore, we reported objectively histopathological irritation signs (irritation scale): strong (folpet), significant (1-bromohexane), slight (MCI/MI at 750/250ppm) and none (isoproturon, bentazon, DEHP and MI). This new in vitro test method presented effective results for the tested chemicals. It should be further validated using a greater number of substances; and tested in different laboratories in order to suitably evaluate reproducibility. Copyright © 2013 Elsevier Ltd. All rights reserved.

Reliability and validity of a brief method to assess nociceptive flexion reflex (NFR) threshold.

PubMed

Rhudy, Jamie L; France, Christopher R

2011-07-01

The nociceptive flexion reflex (NFR) is a physiological tool to study spinal nociception. However, NFR assessment can take several minutes and expose participants to repeated suprathreshold stimulations. The 4 studies reported here assessed the reliability and validity of a brief method to assess NFR threshold that uses a single ascending series of stimulations (Peak 1 NFR), by comparing it to a well-validated method that uses 3 ascending/descending staircases of stimulations (Staircase NFR). Correlations between the NFR definitions were high, were on par with test-retest correlations of Staircase NFR, and were not affected by participant sex or chronic pain status. Results also indicated the test-retest reliabilities for the 2 definitions were similar. Using larger stimulus increments (4 mAs) to assess Peak 1 NFR tended to result in higher NFR threshold estimates than using the Staircase NFR definition, whereas smaller stimulus increments (2 mAs) tended to result in lower NFR threshold estimates than the Staircase NFR definition. Neither NFR definition was correlated with anxiety, pain catastrophizing, or anxiety sensitivity. In sum, a single ascending series of electrical stimulations results in a reliable and valid estimate of NFR threshold. However, caution may be warranted when comparing NFR thresholds across studies that differ in the ascending stimulus increments. This brief method to assess NFR threshold is reliable and valid; therefore, it should be useful to clinical pain researchers interested in quickly assessing inter- and intra-individual differences in spinal nociceptive processes. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

Analytical validation of a new point-of-care assay for serum amyloid A in horses.

PubMed

Schwartz, D; Pusterla, N; Jacobsen, S; Christopher, M M

2018-01-17

Serum amyloid A (SAA) is a major acute phase protein in horses. A new point-of-care (POC) test for SAA (Stablelab) is available, but studies evaluating its analytical accuracy are lacking. To evaluate the analytical performance of the SAA POC test by 1) determining linearity and precision, 2) comparing results in whole blood with those in serum or plasma, and 3) comparing POC results with those obtained using a previously validated turbidimetric immunoassay (TIA). Assay validation. Analytical validation of the POC test was done in accordance with American Society of Veterinary Clinical Pathology guidelines using residual equine serum/plasma and whole blood samples from the Clinical Pathology Laboratory at the University of California-Davis. A TIA was used as the reference method. We also evaluated the effect of haematocrit (HCT). The POC test was linear for SAA concentrations of up to at least 1000 μg/mL (r = 0.991). Intra-assay CVs were 13, 18 and 15% at high (782 μg/mL), intermediate (116 μg/mL) and low (64 μg/mL) concentrations. Inter-assay (inter-batch) CVs were 45, 14 and 15% at high (1372 μg/mL), intermediate (140 μg/mL) and low (56 μg/mL) concentrations. SAA results in whole blood were significantly lower than those in serum/plasma (P = 0.0002), but were positively correlated (r = 0.908) and not affected by HCT (P = 0.261); proportional negative bias was observed in samples with SAA>500 μg/mL. The difference between methods exceeded the 95% confidence interval of the combined imprecision of both methods (15%). Analytical validation could not be performed in whole blood, the sample most likely to be used stall side. The POC test has acceptable accuracy and precision in equine serum/plasma with SAA concentrations of up to at least 1000 μg/mL. Low inter-batch precision at high concentrations may affect serial measurements, and the use of the same test batch and sample type (serum/plasma or whole blood) is recommended. Comparison of results between the POC test and the TIA is not recommended. © 2018 EVJ Ltd.

Sorbent, Sublimation, and Icing Modeling Methods: Experimental Validation and Application to an Integrated MTSA Subassembly Thermal Model

NASA Technical Reports Server (NTRS)

Bower, Chad; Padilla, Sebastian; Iacomini, Christie; Paul, Heather L.

2010-01-01

This paper details the validation of modeling methods for the three core components of a Metabolic heat regenerated Temperature Swing Adsorption (MTSA) subassembly, developed for use in a Portable Life Support System (PLSS). The first core component in the subassembly is a sorbent bed, used to capture and reject metabolically produced carbon dioxide (CO2). The sorbent bed performance can be augmented with a temperature swing driven by a liquid CO2 (LCO2) sublimation heat exchanger (SHX) for cooling the sorbent bed, and a condensing, icing heat exchanger (CIHX) for warming the sorbent bed. As part of the overall MTSA effort, scaled design validation test articles for each of these three components have been independently tested in laboratory conditions. Previously described modeling methodologies developed for implementation in Thermal Desktop and SINDA/FLUINT are reviewed and updated, their application in test article models outlined, and the results of those model correlations relayed. Assessment of the applicability of each modeling methodology to the challenge of simulating the response of the test articles and their extensibility to a full scale integrated subassembly model is given. The independent verified and validated modeling methods are applied to the development of a MTSA subassembly prototype model and predictions of the subassembly performance are given. These models and modeling methodologies capture simulation of several challenging and novel physical phenomena in the Thermal Desktop and SINDA/FLUINT software suite. Novel methodologies include CO2 adsorption front tracking and associated thermal response in the sorbent bed, heat transfer associated with sublimation of entrained solid CO2 in the SHX, and water mass transfer in the form of ice as low as 210 K in the CIHX.

Development of the pediatric quality of life inventory neurofibromatosis type 1 module items for children, adolescents and young adults: qualitative methods.

PubMed

Nutakki, Kavitha; Varni, James W; Steinbrenner, Sheila; Draucker, Claire B; Swigonski, Nancy L

2017-03-01

Health-related quality of life (HRQOL) is arguably one of the most important measures in evaluating effectiveness of clinical treatments. At present, there is no disease-specific outcome measure to assess the HRQOL of children, adolescents and young adults with Neurofibromatosis Type 1 (NF1). This study aimed to develop the items and support the content validity for the Pediatric Quality of Life Inventory™ (PedsQL™) NF1 Module for children, adolescents and young adults. The iterative process included multiphase qualitative methods including a literature review, survey of expert opinions, semi-structured interviews, cognitive interviews and pilot testing. Fifteen domains were derived from the qualitative methods, with content saturation achieved, resulting in 115 items. The domains include skin, pain, pain impact, pain management, cognitive functioning, speech, fine motor, balance, vision, perceived physical appearance, communication, worry, treatment, medicines and gastrointestinal symptoms. This study is limited because all participants are recruited from a single-site. Qualitative methods support the content validity for the PedsQL™ NF1 Module for children, adolescents and young adults. The PedsQL™ NF1 Module is now undergoing national multisite field testing for the psychometric validation of the instrument development.

Initial validation of a web-based self-administered neuropsychological test battery for older adults and seniors

PubMed Central

Hansen, Tor Ivar; Haferstrom, Elise Christina D.; Brunner, Jan F.; Lehn, Hanne; Håberg, Asta Kristine

2015-01-01

Introduction: Computerized neuropsychological tests are effective in assessing different cognitive domains, but are often limited by the need of proprietary hardware and technical staff. Web-based tests can be more accessible and flexible. We aimed to investigate validity, effects of computer familiarity, education, and age, and the feasibility of a new web-based self-administered neuropsychological test battery (Memoro) in older adults and seniors. Method: A total of 62 (37 female) participants (mean age 60.7 years) completed the Memoro web-based neuropsychological test battery and a traditional battery composed of similar tests intended to measure the same cognitive constructs. Participants were assessed on computer familiarity and how they experienced the two batteries. To properly test the factor structure of Memoro, an additional factor analysis in 218 individuals from the HUNT population was performed. Results: Comparing Memoro to traditional tests, we observed good concurrent validity (r = .49–.63). The performance on the traditional and Memoro test battery was consistent, but differences in raw scores were observed with higher scores on verbal memory and lower in spatial memory in Memoro. Factor analysis indicated two factors: verbal and spatial memory. There were no correlations between test performance and computer familiarity after adjustment for age or age and education. Subjects reported that they preferred web-based testing as it allowed them to set their own pace, and they did not feel scrutinized by an administrator. Conclusions: Memoro showed good concurrent validity compared to neuropsychological tests measuring similar cognitive constructs. Based on the current results, Memoro appears to be a tool that can be used to assess cognitive function in older and senior adults. Further work is necessary to ascertain its validity and reliability. PMID:26009791

Validation of Modifications to the ANSR for Listeria Method for Improved Internal Positive Control Performance.

PubMed

Alles, Susan; Meister, Evan; Hosking, Edan; Tovar, Eric; Shaulis, Rebecca; Schonfeld, Mark; Zhang, Lei; Li, Lin; Biswas, Preetha; Mozola, Mark; Donofrio, Robert; Chen, Yi

2018-03-01

A study was conducted to validate a minor reagent formulation change to the ANSR for Listeria method, Performance Tested MethodSM 101202. This change involves increasing the master mix volume prelyophilization by 40% and addition of salmon sperm DNA (nontarget DNA) to the master mix. These changes improve the robustness of the internal positive control response and reduce the possibility of obtaining invalid results due to weak-positive control curves. When three foods (hot dogs, Mexican-style cheese, and cantaloupe) and sponge samples taken from a stainless steel surface were tested, no significant differences in performance between the ANSR and U.S. Food and Drug Administration Bacteriological Analytical Manual or U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedures were observed for any of the matrixes as determined by probability of detection analysis. Inclusivity and exclusivity testing yielded 100% expected results for target and nontarget bacteria. Accelerated stability testing was carried out over a 7 week period and showed no decrease in assay performance over time.

Development and testing of the questionnaire CEC-61: Knowledge about cervical cancer in Chilean adolescents.

PubMed

Urrutia, María Teresa; Gajardo, Macarena; Padilla, Oslando

2017-05-22

Despite a clear association between human papillomavirus and cervical cancer, knowledge in adolescent populations regarding the disease and methods for its detection and prevention is deficient. The aim of this study was to develop and test a new questionnaire concerning knowledge on cervical cancer. An instrument was developed and validated to measure knowledge in 226 Chilean adolescents between April and June 2011. Content validity, construct validity, and reliability analysis of the instrument were performed. The new, validated instrument, called CEC-61 (Conocimientos en Cancer Cérvicouterino-61 items/Knowledge in Cervical Cancer-61 items), contains nine factors and 61 items. The new questionnaire explained 81% of the variance with a reliability of 0.96. The assessment of knowledge with a valid and reliable instrument is the first step in creating interventions for a population and to encourage appropriate preventive behavior. CEC-61 is highly reliable and has a clear factorial structure to evaluate knowledge in nine domains related to cervical cancer disease, cervical cancer risk, papilloma virus infection, the Papanicolaou test, and the papilloma virus vaccine.

Hypothesis testing for the validation of the kinetic spectrophotometric methods for the determination of lansoprazole in bulk and drug formulations via Fe(III) and Zn(II) chelates.

PubMed

Rahman, Nafisur; Kashif, Mohammad

2010-03-01

Point and interval hypothesis tests performed to validate two simple and economical, kinetic spectrophotometric methods for the assay of lansoprazole are described. The methods are based on the formation of chelate complex of the drug with Fe(III) and Zn(II). The reaction is followed spectrophotometrically by measuring the rate of change of absorbance of coloured chelates of the drug with Fe(III) and Zn(II) at 445 and 510 nm, respectively. The stoichiometric ratio of lansoprazole to Fe(III) and Zn(II) complexes were found to be 1:1 and 2:1, respectively. The initial-rate and fixed-time methods are adopted for determination of drug concentrations. The calibration graphs are linear in the range 50-200 µg ml⁻¹ (initial-rate method), 20-180 µg ml⁻¹ (fixed-time method) for lansoprazole-Fe(III) complex and 120-300 (initial-rate method), and 90-210 µg ml⁻¹ (fixed-time method) for lansoprazole-Zn(II) complex. The inter-day and intra-day precision data showed good accuracy and precision of the proposed procedure for analysis of lansoprazole. The point and interval hypothesis tests indicate that the proposed procedures are not biased. Copyright © 2010 John Wiley & Sons, Ltd.

Unproven techniques in allergy diagnosis.

PubMed

Wüthrich, B

2005-01-01

Mainstream allergy diagnosis and treatment is based on classical allergy testing which involves well-validated diagnostic methods and proven methods of treatment. By contrast, a number of unproven tests have been proposed for evaluating allergic patients including cytotoxic food testing, ALCAT test, bioresonance, electrodermal testing (electroacupuncture), reflexology, applied kinesiology a.o. There is little or no scientific rationale for these methods. Results are not reproducible when subject to rigorous testing and do not correlate with clinical evidence of allergy. Although some papers suggest a possible pathogenetic role of IgG, IgG4 antibody, no correlation was found between the outcome of DBPCFC and the levels of either food-specific IgG or IgG4, nor was any difference seen between patients and controls. The levels of these and other food-specific immunoglobulins of non-IgE isotype reflect the intake of food in the individual and may thus be a normal and harmless finding. The so-called "Food Allergy Profile" with simultaneous IgE and IgG determination against more than 100 foodstuffs is neither economical nor useful for diagnosis. DBPCFC must be the reference standard for food hypersensitivity and any new test must be validated by it. As a result, all these unproven techniques may lead to misleading advice or treatments, and their use is not advised.

Traceability validation of a high speed short-pulse testing method used in LED production

NASA Astrophysics Data System (ADS)

Revtova, Elena; Vuelban, Edgar Moreno; Zhao, Dongsheng; Brenkman, Jacques; Ulden, Henk

2017-12-01

Industrial processes of LED (light-emitting diode) production include LED light output performance testing. Most of them are monitored and controlled by optically, electrically and thermally measuring LEDs by high speed short-pulse measurement methods. However, these are not standardized and a lot of information is proprietary that it is impossible for third parties, such as NMIs, to trace and validate. It is known, that these techniques have traceability issue and metrological inadequacies. Often due to these, the claimed performance specifications of LEDs are overstated, which consequently results to manufacturers experiencing customers' dissatisfaction and a large percentage of failures in daily use of LEDs. In this research a traceable setup is developed to validate one of the high speed testing techniques, investigate inadequacies and work out the traceability issues. A well-characterised short square pulse of 25 ms is applied to chip-on-board (CoB) LED modules to investigate the light output and colour content. We conclude that the short-pulse method is very efficient in case a well-defined electrical current pulse is applied and the stabilization time of the device is "a priori" accurately determined. No colour shift is observed. The largest contributors to the measurement uncertainty include badly-defined current pulse and inaccurate calibration factor.

Alternatives to animal testing: research, trends, validation, regulatory acceptance.

PubMed

Huggins, Jane

2003-01-01

Current trends and issues in the development of alternatives to the use of animals in biomedical experimentation are discussed in this position paper. Eight topics are considered and include refinement of acute toxicity assays; eye corrosion/irritation alternatives; skin corrosion/irritation alternatives; contact sensitization alternatives; developmental/reproductive testing alternatives; genetic engineering (transgenic) assays; toxicogenomics; and validation of alternative methods. The discussion of refinement of acute toxicity assays is focused primarily on developments with regard to reduction of the number of animals used in the LD(50) assay. However, the substitution of humane endpoints such as clinical signs of toxicity for lethality in these assays is also evaluated. Alternative assays for eye corrosion/irritation as well as those for skin corrosion/irritation are described with particular attention paid to the outcomes, both successful and unsuccessful, of several validation efforts. Alternative assays for contact sensitization and developmental/reproductive toxicity are presented as examples of methods designed for the examination of interactions between toxins and somewhat more complex physiological systems. Moreover, genetic engineering and toxicogenomics are discussed with an eye toward the future of biological experimentation in general. The implications of gene manipulation for research animals, specifically, are also examined. Finally, validation methods are investigated as to their effectiveness, or lack thereof, and suggestions for their standardization and improvement, as well as implementation are reviewed.

Fuzzy Logic Controller Stability Analysis Using a Satisfiability Modulo Theories Approach

NASA Technical Reports Server (NTRS)

Arnett, Timothy; Cook, Brandon; Clark, Matthew A.; Rattan, Kuldip

2017-01-01

While many widely accepted methods and techniques exist for validation and verification of traditional controllers, at this time no solutions have been accepted for Fuzzy Logic Controllers (FLCs). Due to the highly nonlinear nature of such systems, and the fact that developing a valid FLC does not require a mathematical model of the system, it is quite difficult to use conventional techniques to prove controller stability. Since safety-critical systems must be tested and verified to work as expected for all possible circumstances, the fact that FLC controllers cannot be tested to achieve such requirements poses limitations on the applications for such technology. Therefore, alternative methods for verification and validation of FLCs needs to be explored. In this study, a novel approach using formal verification methods to ensure the stability of a FLC is proposed. Main research challenges include specification of requirements for a complex system, conversion of a traditional FLC to a piecewise polynomial representation, and using a formal verification tool in a nonlinear solution space. Using the proposed architecture, the Fuzzy Logic Controller was found to always generate negative feedback, but inconclusive for Lyapunov stability.

The dialysis orders objective structured clinical examination (OSCE): a formative assessment for nephrology fellows

PubMed Central

Prince, Lisa K; Campbell, Ruth C; Gao, Sam W; Kendrick, Jessica; Lebrun, Christopher J; Little, Dustin J; Mahoney, David L; Maursetter, Laura A; Nee, Robert; Saddler, Mark; Watson, Maura A

2018-01-01

Abstract Background Few quantitative nephrology-specific simulations assess fellow competency. We describe the development and initial validation of a formative objective structured clinical examination (OSCE) assessing fellow competence in ordering acute dialysis. Methods The three test scenarios were acute continuous renal replacement therapy, chronic dialysis initiation in moderate uremia and acute dialysis in end-stage renal disease-associated hyperkalemia. The test committee included five academic nephrologists and four clinically practicing nephrologists outside of academia. There were 49 test items (58 points). A passing score was 46/58 points. No item had median relevance less than ‘important’. The content validity index was 0.91. Ninety-five percent of positive-point items were easy–medium difficulty. Preliminary validation was by 10 board-certified volunteers, not test committee members, a median of 3.5 years from graduation. The mean score was 49 [95% confidence interval (CI) 46–51], κ = 0.68 (95% CI 0.59–0.77), Cronbach’s α = 0.84. Results We subsequently administered the test to 25 fellows. The mean score was 44 (95% CI 43–45); 36% passed the test. Fellows scored significantly less than validators (P < 0.001). Of evidence-based questions, 72% were answered correctly by validators and 54% by fellows (P = 0.018). Fellows and validators scored least well on the acute hyperkalemia question. In self-assessing proficiency, 71% of fellows surveyed agreed or strongly agreed that the OSCE was useful. Conclusions The OSCE may be used to formatively assess fellow proficiency in three common areas of acute dialysis practice. Further validation studies are in progress. PMID:29644053

Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study

PubMed Central

2013-01-01

Background Bullying (Bull) is a public health problem worldwide, and Mexico is not exempt. However, its epidemiology and early detection in our country is limited, in part, by the lack of validated tests to ensure the respondents’ anonymity. The aim of this study was to validate a self-administered test (Bull-M) for assessing Bull among high-school Mexicans. Methods Experts and school teachers from highly violent areas of Ciudad Juarez (Chihuahua, México), reported common Bull behaviors. Then, a 10-item test was developed based on twelve of these behaviors; the students’ and peers’ participation in Bull acts and in some somatic consequences in Bull victims with a 5-point Likert frequency scale. Validation criteria were: content (CV, judges); reliability [Cronbach’s alpha (CA), test-retest (spearman correlation, rs)]; construct [principal component (PCA), confirmatory factor (CFA), goodness-of-fit (GF) analysis]; and convergent (Bull-M vs. Bull-S test) validity. Results Bull-M showed good reliability (CA = 0.75, rs = 0.91; p < 0.001). Two factors were identified (PCA) and confirmed (CFA): “bullying me (victim)” and “bullying others (aggressor)”. GF indices were: Root mean square error of approximation (0.031), GF index (0.97), and normalized fit index (0.92). Bull-M was as good as Bull-S for measuring Bull prevalence. Conclusions Bull-M has a good reliability and convergent validity and a bi-modal factor structure for detecting Bull victims and aggressors; however, its external validity and sensitivity should be analyzed on a wider and different population. PMID:23577755

The ICR96 exon CNV validation series: a resource for orthogonal assessment of exon CNV calling in NGS data.

PubMed

Mahamdallie, Shazia; Ruark, Elise; Yost, Shawn; Ramsay, Emma; Uddin, Imran; Wylie, Harriett; Elliott, Anna; Strydom, Ann; Renwick, Anthony; Seal, Sheila; Rahman, Nazneen

2017-01-01

Detection of deletions and duplications of whole exons (exon CNVs) is a key requirement of genetic testing. Accurate detection of this variant type has proved very challenging in targeted next-generation sequencing (NGS) data, particularly if only a single exon is involved. Many different NGS exon CNV calling methods have been developed over the last five years. Such methods are usually evaluated using simulated and/or in-house data due to a lack of publicly-available datasets with orthogonally generated results. This hinders tool comparisons, transparency and reproducibility. To provide a community resource for assessment of exon CNV calling methods in targeted NGS data, we here present the ICR96 exon CNV validation series. The dataset includes high-quality sequencing data from a targeted NGS assay (the TruSight Cancer Panel) together with Multiplex Ligation-dependent Probe Amplification (MLPA) results for 96 independent samples. 66 samples contain at least one validated exon CNV and 30 samples have validated negative results for exon CNVs in 26 genes. The dataset includes 46 exon CNVs in BRCA1 , BRCA2 , TP53 , MLH1 , MSH2 , MSH6 , PMS2 , EPCAM or PTEN , giving excellent representation of the cancer predisposition genes most frequently tested in clinical practice. Moreover, the validated exon CNVs include 25 single exon CNVs, the most difficult type of exon CNV to detect. The FASTQ files for the ICR96 exon CNV validation series can be accessed through the European-Genome phenome Archive (EGA) under the accession number EGAS00001002428.

Validation (not just verification) of Deep Space Missions

NASA Technical Reports Server (NTRS)

Duren, Riley M.

2006-01-01

ion & Validation (V&V) is a widely recognized and critical systems engineering function. However, the often used definition 'Verification proves the design is right; validation proves it is the right design' is rather vague. And while Verification is a reasonably well standardized systems engineering process, Validation is a far more abstract concept and the rigor and scope applied to it varies widely between organizations and individuals. This is reflected in the findings in recent Mishap Reports for several NASA missions, in which shortfalls in Validation (not just Verification) were cited as root- or contributing-factors in catastrophic mission loss. Furthermore, although there is strong agreement in the community that Test is the preferred method for V&V, many people equate 'V&V' with 'Test', such that Analysis and Modeling aren't given comparable attention. Another strong motivator is a realization that the rapid growth in complexity of deep-space missions (particularly Planetary Landers and Space Observatories given their inherent unknowns) is placing greater demands on systems engineers to 'get it right' with Validation.

Validation on milk and sprouts of EN ISO 16654:2001 - Microbiology of food and animal feeding stuffs - Horizontal method for the detection of Escherichia coli O157.

PubMed

Tozzoli, Rosangela; Maugliani, Antonella; Michelacci, Valeria; Minelli, Fabio; Caprioli, Alfredo; Morabito, Stefano

2018-05-08

In 2006, the European Committee for standardisation (CEN)/Technical Committee 275 - Food analysis - Horizontal methods/Working Group 6 - Microbiology of the food chain (TC275/WG6), launched the project of validating the method ISO 16654:2001 for the detection of Escherichia coli O157 in foodstuff by the evaluation of its performance, in terms of sensitivity and specificity, through collaborative studies. Previously, a validation study had been conducted to assess the performance of the Method No 164 developed by the Nordic Committee for Food Analysis (NMKL), which aims at detecting E. coli O157 in food as well, and is based on a procedure equivalent to that of the ISO 16654:2001 standard. Therefore, CEN established that the validation data obtained for the NMKL Method 164 could be exploited for the ISO 16654:2001 validation project, integrated with new data obtained through two additional interlaboratory studies on milk and sprouts, run in the framework of the CEN mandate No. M381. The ISO 16654:2001 validation project was led by the European Union Reference Laboratory for Escherichia coli including VTEC (EURL-VTEC), which organized the collaborative validation study on milk in 2012 with 15 participating laboratories and that on sprouts in 2014, with 14 participating laboratories. In both studies, a total of 24 samples were tested by each laboratory. Test materials were spiked with different concentration of E. coli O157 and the 24 samples corresponded to eight replicates of three levels of contamination: zero, low and high spiking level. The results submitted by the participating laboratories were analyzed to evaluate the sensitivity and specificity of the ISO 16654:2001 method when applied to milk and sprouts. The performance characteristics calculated on the data of the collaborative validation studies run under the CEN mandate No. M381 returned sensitivity and specificity of 100% and 94.4%, respectively for the milk study. As for sprouts matrix, the sensitivity resulted in 75.9% in the low level of contamination samples and 96.4% in samples spiked with high level of E. coli O157 and specificity was calculated as 99.1%. Copyright © 2018 Elsevier B.V. All rights reserved.

Reliability and validity of three pain provocation tests used for the diagnosis of chronic proximal hamstring tendinopathy.

PubMed

Cacchio, Angelo; Borra, Fabrizio; Severini, Gabriele; Foglia, Andrea; Musarra, Frank; Taddio, Nicola; De Paulis, Fosco

2012-09-01

The clinical assessment of chronic proximal hamstring tendinopathy (PHT) in athletes is a challenge to sports medicine. To be able to compare the results of research and treatments, the methods used to diagnose and evaluate PHT must be clearly defined and reproducible. To assess the reliability and validity of three pain provocation tests used for the diagnosis of PHT. Ninety-two athletes with (N=46) and without (N=46) PHT were examined by one physician and two physiotherapists, who were trained in the examination techniques before the study. The examiners were blinded to the symptoms and identity of the athletes. The three pain provocation tests examined were the Puranen-Orava, bent-knee stretch and modified bent-knee stretch tests. Intraclass correlation coefficients (ICCs) based on the repeated measures analysis of variance were used to analyse the intraexaminer and interexaminer reliability, while sensitivity, specificity, predictive values and likelihood ratios were used to determine the validity of the three tests. The ICC values in all three tests revealed a high correlation (range 0.82 to 0.88) for the interexaminer reliability and a high-to-very high correlation (range 0.87 to 0.93) for the intraexaminer reliability. All three tests displayed a moderate-to-high validity, with the highest degree of validity being yielded by the modified bent-knee stretch test. All three pain provocation tests proved to be of potential value in assessing chronic PHT in athletes. However, we recommend that they be used in conjunction with other objective measures, such as MRI.

Corpus Linguistics and Language Testing: Navigating Uncharted Waters

ERIC Educational Resources Information Center

Egbert, Jesse

2017-01-01

The use of corpora and corpus linguistic methods in language testing research is increasing at an accelerated pace. The growing body of language testing research that uses corpus linguistic data is a testament to their utility in test development and validation. Although there are many reasons to be optimistic about the future of using corpus data…

Validity and Reliability of the Turkish Version of Needs Based Biopsychosocial Distress Instrument for Cancer Patients (CANDI)

PubMed Central

Beyhun, Nazim Ercument; Can, Gamze; Tiryaki, Ahmet; Karakullukcu, Serdar; Bulut, Bekir; Yesilbas, Sehbal; Kavgaci, Halil; Topbas, Murat

2016-01-01

Background Needs based biopsychosocial distress instrument for cancer patients (CANDI) is a scale based on needs arising due to the effects of cancer. Objectives The aim of this research was to determine the reliability and validity of the CANDI scale in the Turkish language. Patients and Methods The study was performed with the participation of 172 cancer patients aged 18 and over. Factor analysis (principal components analysis) was used to assess construct validity. Criterion validities were tested by computing Spearman correlation between CANDI and hospital anxiety depression scale (HADS), and brief symptom inventory (BSI) (convergent validity) and quality of life scales (FACT-G) (divergent validity). Test-retest reliabilities and internal consistencies were measured with intraclass correlation (ICC) and Cronbach-α. Results A three-factor solution (emotional, physical and social) was found with factor analysis. Internal reliability (α = 0.94) and test-retest reliability (ICC = 0.87) were significantly high. Correlations between CANDI and HADS (rs = 0.67), and BSI (rs = 0.69) and FACT-G (rs = -0.76) were moderate and significant in the expected direction. Conclusions CANDI is a valid and reliable scale in cancer patients with a three-factor structure (emotional, physical and social) in the Turkish language. PMID:27621931

Rapid determination of residues of pesticides in honey by µGC-ECD and GC-MS/MS: Method validation and estimation of measurement uncertainty according to document No. SANCO/12571/2013.

PubMed

Paoloni, Angela; Alunni, Sabrina; Pelliccia, Alessandro; Pecorelli, Ivan

2016-01-01

A simple and straightforward method for simultaneous determination of residues of 13 pesticides in honey samples (acrinathrin, bifenthrin, bromopropylate, cyhalothrin-lambda, cypermethrin, chlorfenvinphos, chlorpyrifos, coumaphos, deltamethrin, fluvalinate-tau, malathion, permethrin and tetradifon) from different pesticide classes has been developed and validated. The analytical method provides dissolution of honey in water and an extraction of pesticide residues by n-Hexane followed by clean-up on a Florisil SPE column. The extract was evaporated and taken up by a solution of an injection internal standard (I-IS), ethion, and finally analyzed by capillary gas chromatography with electron capture detection (GC-µECD). Identification for qualitative purpose was conducted by gas chromatography with triple quadrupole mass spectrometer (GC-MS/MS). A matrix-matched calibration curve was performed for quantitative purposes by plotting the area ratio (analyte/I-IS) against concentration using a GC-µECD instrument. According to document No. SANCO/12571/2013, the method was validated by testing the following parameters: linearity, matrix effect, specificity, precision, trueness (bias) and measurement uncertainty. The analytical process was validated analyzing blank honey samples spiked at levels equal to and greater than 0.010 mg/kg (limit of quantification). All parameters were satisfactorily compared with the values established by document No. SANCO/12571/2013. The analytical performance was verified by participating in eight multi-residue proficiency tests organized by BIPEA, obtaining satisfactory z-scores in all 70 determinations. Measurement uncertainty was estimated according to the top-down approaches described in Appendix C of the SANCO document using the within-laboratory reproducibility relative standard deviation combined with laboratory bias using the proficiency test data.

Development and Validation of High Performance Liquid Chromatography Method for Determination Atorvastatin in Tablet

NASA Astrophysics Data System (ADS)

Yugatama, A.; Rohmani, S.; Dewangga, A.

2018-03-01

Atorvastatin is the primary choice for dyslipidemia treatment. Due to patent expiration of atorvastatin, the pharmaceutical industry makes copy of the drug. Therefore, the development methods for tablet quality tests involving atorvastatin concentration on tablets needs to be performed. The purpose of this research was to develop and validate the simple atorvastatin tablet analytical method by HPLC. HPLC system used in this experiment consisted of column Cosmosil C18 (150 x 4,6 mm, 5 µm) as the stationary reverse phase chomatography, a mixture of methanol-water at pH 3 (80:20 v/v) as the mobile phase, flow rate of 1 mL/min, and UV detector at wavelength of 245 nm. Validation methods were including: selectivity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantitation (LOQ). The results of this study indicate that the developed method had good validation including selectivity, linearity, accuracy, precision, LOD, and LOQ for analysis of atorvastatin tablet content. LOD and LOQ were 0.2 and 0.7 ng/mL, and the linearity range were 20 - 120 ng/mL.

Development of Two-Tier Diagnostic Test Pictorial-Based for Identifying High School Students Misconceptions on the Mole Concept

NASA Astrophysics Data System (ADS)

Siswaningsih, W.; Firman, H.; Zackiyah; Khoirunnisa, A.

2017-02-01

The aim of this study was to develop the two-tier pictorial-based diagnostic test for identifying student misconceptions on mole concept. The method of this study is used development and validation. The development of the test Obtained through four phases, development of any items, validation, determination key, and application test. Test was developed in the form of pictorial consisting of two tier, the first tier Consist of four possible answers and the second tier Consist of four possible reasons. Based on the results of content validity of 20 items using the CVR (Content Validity Ratio), a number of 18 items declared valid. Based on the results of the reliability test using SPSS, Obtained 17 items with Cronbach’s Alpha value of 0703, the which means that items have accepted. A total of 10 items was conducted to 35 students of senior high school students who have studied the mole concept on one of the high schools in Cimahi. Based on the results of the application test, student misconceptions were identified in each label concept in mole concept with the percentage of misconceptions on the label concept of mole (60.15%), Avogadro’s number (34.28%), relative atomic mass (62, 84%), relative molecule mass (77.08%), molar mass (68.53%), molar volume of gas (57.11%), molarity (71.32%), chemical equation (82.77%), limiting reactants (91.40%), and molecular formula (77.13%).

40 CFR 63.642 - General standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... reduction. (4) Data shall be reduced in accordance with the EPA-approved methods specified in the applicable section or, if other test methods are used, the data and methods shall be validated according to the protocol in Method 301 of appendix A of this part. (e) Each owner or operator of a source subject to this...

Validation and Test-Retest Reliability of New Thermographic Technique Called Thermovision Technique of Dry Needling for Gluteus Minimus Trigger Points in Sciatica Subjects and TrPs-Negative Healthy Volunteers

PubMed Central

Rychlik, Michał; Samborski, Włodzimierz

2015-01-01

The aim of this study was to assess the validity and test-retest reliability of Thermovision Technique of Dry Needling (TTDN) for the gluteus minimus muscle. TTDN is a new thermography approach used to support trigger points (TrPs) diagnostic criteria by presence of short-term vasomotor reactions occurring in the area where TrPs refer pain. Method. Thirty chronic sciatica patients (n=15 TrP-positive and n=15 TrPs-negative) and 15 healthy volunteers were evaluated by TTDN three times during two consecutive days based on TrPs of the gluteus minimus muscle confirmed additionally by referred pain presence. TTDN employs average temperature (T avr), maximum temperature (T max), low/high isothermal-area, and autonomic referred pain phenomenon (AURP) that reflects vasodilatation/vasoconstriction. Validity and test-retest reliability were assessed concurrently. Results. Two components of TTDN validity and reliability, T avr and AURP, had almost perfect agreement according to κ (e.g., thigh: 0.880 and 0.938; calf: 0.902 and 0.956, resp.). The sensitivity for T avr, T max, AURP, and high isothermal-area was 100% for everyone, but specificity of 100% was for T avr and AURP only. Conclusion. TTDN is a valid and reliable method for T avr and AURP measurement to support TrPs diagnostic criteria for the gluteus minimus muscle when digitally evoked referred pain pattern is present. PMID:26137486

Unavoidable Pressure Ulcers: Development and Testing of the Indiana University Health Pressure Ulcer Prevention Inventory.

PubMed

Pittman, Joyce; Beeson, Terrie; Terry, Colin; Dillon, Jill; Hampton, Charity; Kerley, Denise; Mosier, Judith; Gumiela, Ellen; Tucker, Jessica

2016-01-01

Despite prevention strategies, hospital-acquired pressure ulcers (HAPUs) continue to occur in the acute care setting. The purpose of this study was to develop an operational definition of and an instrument for identifying avoidable/unavoidable HAPUs in the acute care setting. The Indiana University Health Pressure Ulcer Prevention Inventory (PUPI) was developed and psychometric testing was performed. A retrospective pilot study of 31 adult hospitalized patients with an HAPU was conducted using the PUPI. Overall content validity index of 0.99 and individual item content validity index scores (0.9-1.0) demonstrated excellent content validity. Acceptable PUPI criterion validity was demonstrated with no statistically significant differences between wound specialists' and other panel experts' scoring. Construct validity findings were acceptable with no statistically significant differences among avoidable or unavoidable HAPU patients and their Braden Scale total scores. Interrater reliability was acceptable with perfect agreement on the total PUPI score between raters (κ = 1.0; P = .025). Raters were in total agreement 93% (242/260) of the time on all 12 individual PUPI items. No risk factors were found to be significantly associated with unavoidable HAPUs. An operational definition of and an instrument for identifying avoidable/unavoidable HAPUs in the acute care setting were developed and tested. The instrument provides an objective and structured method for identifying avoidable/unavoidable HAPUs. The PUPI provides an additional method that could be used in root-cause analyses and when reporting adverse pressure ulcer events.

Development and Validation of Discriminating and Biorelevant Dissolution Test for Lornoxicam Tablets

PubMed Central

Anumolu, P. D.; Sunitha, G.; Bindu, S. Hima; Satheshbabu, P. R.; Subrahmanyam, C. V. S.

2015-01-01

The establishment of biorelevant and discriminating dissolution procedure for drug products with limited water solubility is a useful technique for qualitative forecasting of the in vivo behavior of formulations. It also characterizes the drug product performance in pharmaceutical development. Lornoxicam, a BCS class-II drug is a nonsteroidal antiinflammatory drug of the oxicam class, has no official dissolution media available in the literature. The objective of present work was to develop and validate a discriminating and biorelevant dissolution test for lornoxicam tablet dosage forms. To quantify the lornoxicam in dissolution samples, UV spectrophotometric method was developed using 0.01M sodium hydroxide solution as solvent at λma×376 nm. After evaluation of saturation solubility, dissolution, sink conditions and stability of lornoxicam bulk drug in different pH solutions and biorelevant media, the dissolution method was optimized using USP paddle type apparatus at 50 rpm rotation speed and 500 ml simulated intestinal fluid as discriminating and biorelevant dissolution medium. The similarity factor (f2) were investigated for formulations with changes in composition and manufacturing variations, values revealed that dissolution method having discriminating power and method was validated as per standard guidelines. The proposed dissolution method can be effectively applied for routine quality control in vitro dissolution studies of lornoxicam in tablets and helpful to pharmacopoeias. PMID:26180277