Few items in the thyroid-related quality of life instrument ThyPRO exhibited differential item functioning

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Watt, Torquil; Grønvold, Mogens; Hegedüs, Laszlo

2014-01-01

To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis.......To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis....

Few items in the thyroid-related quality of life instrument ThyPRO exhibited differential item functioning.

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Watt, Torquil; Groenvold, Mogens; Hegedüs, Laszlo; Bonnema, Steen Joop; Rasmussen, Åse Krogh; Feldt-Rasmussen, Ulla; Bjorner, Jakob Bue

2014-02-01

To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis. A total of 838 patients with benign thyroid diseases completed the ThyPRO questionnaire (84 five-point items, 13 scales). Uniform and nonuniform DIF were investigated using ordinal logistic regression, testing for both statistical significance and magnitude (∆R(2) > 0.02). Scale level was estimated by the sum score, after purification. Twenty instances of DIF in 17 of the 84 items were found. Eight according to diagnosis, where the goiter scale was the one most affected, possibly due to differing perceptions in patients with auto-immune thyroid diseases compared to patients with simple goiter. Eight DIFs according to age were found, of which 5 were in positively worded items, which younger patients were more likely to endorse; one according to gender: women were more likely to report crying, and three according to educational level. The vast majority of DIF had only minor influence on the scale scores (0.1-2.3 points on the 0-100 scales), but two DIF corresponded to a difference of 4.6 and 9.8, respectively. Ordinal logistic regression identified DIF in 17 of 84 items. The potential impact of this on the present scales was low, but items displaying DIF could be avoided when developing abbreviated scales, where the potential impact of DIF (due to fewer items) will be larger.

Item Response Theory with Covariates (IRT-C): Assessing Item Recovery and Differential Item Functioning for the Three-Parameter Logistic Model

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Tay, Louis; Huang, Qiming; Vermunt, Jeroen K.

2016-01-01

In large-scale testing, the use of multigroup approaches is limited for assessing differential item functioning (DIF) across multiple variables as DIF is examined for each variable separately. In contrast, the item response theory with covariate (IRT-C) procedure can be used to examine DIF across multiple variables (covariates) simultaneously. To…

A scale purification procedure for evaluation of differential item functioning

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Khalid, Muhammad Naveed; Glas, Cornelis A.W.

2014-01-01

Item bias or differential item functioning (DIF) has an important impact on the fairness of psychological and educational testing. In this paper, DIF is seen as a lack of fit to an item response (IRT) model. Inferences about the presence and importance of DIF require a process of so-called test

"Detecting Differential Item Functioning and Differential Step Functioning due to Differences that ""Should"" Matter"

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Tess Miller

2010-07-01

Full Text Available This study illustrates the use of differential item functioning (DIF and differential step functioning (DSF analyses to detect differences in item difficulty that are related to experiences of examinees, such as their teachers' instructional practices, that are relevant to the knowledge, skill, or ability the test is intended to measure. This analysis is in contrast to the typical use of DIF or DSF to detect differences related to characteristics of examinees, such as gender, language, or cultural knowledge, that should be irrelevant. Using data from two forms of Ontario's Grade 9 Assessment of Mathematics, analyses were performed comparing groups of students defined by their teachers' instructional practices. All constructed-response items were tested for DIF using the Mantel Chi-Square, standardized Liu Agresti cumulative common log-odds ratio, and standardized Cox's noncentrality parameter. Items exhibiting moderate to large DIF were subsequently tested for DSF. In contrast to typical DIF or DSF analyses, which inform item development, these analyses have the potential to inform instructional practice.

Exploring differential item functioning in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC

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Pollard Beth

2012-12-01

Full Text Available Abstract Background The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC is a widely used patient reported outcome in osteoarthritis. An important, but frequently overlooked, aspect of validating health outcome measures is to establish if items exhibit differential item functioning (DIF. That is, if respondents have the same underlying level of an attribute, does the item give the same score in different subgroups or is it biased towards one subgroup or another. The aim of the study was to explore DIF in the Likert format WOMAC for the first time in a UK osteoarthritis population with respect to demographic, social, clinical and psychological factors. Methods The sample comprised a community sample of 763 people with osteoarthritis who participated in the Somerset and Avon Survey of Health. The WOMAC was explored for DIF by gender, age, social deprivation, social class, employment status, distress, body mass index and clinical factors. Ordinal regression models were used to identify DIF items. Results After adjusting for age, two items were identified for the physical functioning subscale as having DIF with age identified as the DIF factor for 2 items, gender for 1 item and body mass index for 1 item. For the WOMAC pain subscale, for people with hip osteoarthritis one item was identified with age-related DIF. The impact of the DIF items rarely had a significant effect on the conclusions of group comparisons. Conclusions Overall, the WOMAC performed well with only a small number of DIF items identified. However, as DIF items were identified in for the WOMAC physical functioning subscale it would be advisable to analyse data taking into account the possible impact of the DIF items when weight, gender or especially age effects, are the focus of interest in UK-based osteoarthritis studies. Similarly for the WOMAC pain subscale in people with hip osteoarthritis it would be worthwhile to analyse data taking into account the

Detection of differential item functioning using Lagrange multiplier tests

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Glas, Cornelis A.W.

1996-01-01

In this paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or C. R. Rao's efficient score test. The test is presented in the framework of a number of item response theory (IRT) models such as the Rasch model, the one-parameter logistic model, the

Language-related differential item functioning between English and German PROMIS Depression items is negligible.

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Fischer, H Felix; Wahl, Inka; Nolte, Sandra; Liegl, Gregor; Brähler, Elmar; Löwe, Bernd; Rose, Matthias

2017-12-01

To investigate differential item functioning (DIF) of PROMIS Depression items between US and German samples we compared data from the US PROMIS calibration sample (n = 780), a German general population survey (n = 2,500) and a German clinical sample (n = 621). DIF was assessed in an ordinal logistic regression framework, with 0.02 as criterion for R 2 -change and 0.096 for Raju's non-compensatory DIF. Item parameters were initially fixed to the PROMIS Depression metric; we used plausible values to account for uncertainty in depression estimates. Only four items showed DIF. Accounting for DIF led to negligible effects for the full item bank as well as a post hoc simulated computer-adaptive test (German general population sample was considerably lower compared to the US reference value of 50. Overall, we found little evidence for language DIF between US and German samples, which could be addressed by either replacing the DIF items by items not showing DIF or by scoring the short form in German samples with the corrected item parameters reported. Copyright © 2016 John Wiley & Sons, Ltd.

Detection of Uniform and Nonuniform Differential Item Functioning by Item-Focused Trees

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Berger, Moritz; Tutz, Gerhard

2016-01-01

Detection of differential item functioning (DIF) by use of the logistic modeling approach has a long tradition. One big advantage of the approach is that it can be used to investigate nonuniform (NUDIF) as well as uniform DIF (UDIF). The classical approach allows one to detect DIF by distinguishing between multiple groups. We propose an…

Do people with and without medical conditions respond similarly to the short health anxiety inventory? An assessment of differential item functioning using item response theory.

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LeBouthillier, Daniel M; Thibodeau, Michel A; Alberts, Nicole M; Hadjistavropoulos, Heather D; Asmundson, Gordon J G

2015-04-01

Individuals with medical conditions are likely to have elevated health anxiety; however, research has not demonstrated how medical status impacts response patterns on health anxiety measures. Measurement bias can undermine the validity of a questionnaire by overestimating or underestimating scores in groups of individuals. We investigated whether the Short Health Anxiety Inventory (SHAI), a widely-used measure of health anxiety, exhibits medical condition-based bias on item and subscale levels, and whether the SHAI subscales adequately assess the health anxiety continuum. Data were from 963 individuals with diabetes, breast cancer, or multiple sclerosis, and 372 healthy individuals. Mantel-Haenszel tests and item characteristic curves were used to classify the severity of item-level differential item functioning in all three medical groups compared to the healthy group. Test characteristic curves were used to assess scale-level differential item functioning and whether the SHAI subscales adequately assess the health anxiety continuum. Nine out of 14 items exhibited differential item functioning. Two items exhibited differential item functioning in all medical groups compared to the healthy group. In both Thought Intrusion and Fear of Illness subscales, differential item functioning was associated with mildly deflated scores in medical groups with very high levels of the latent traits. Fear of Illness items poorly discriminated between individuals with low and very low levels of the latent trait. While individuals with medical conditions may respond differentially to some items, clinicians and researchers can confidently use the SHAI with a variety of medical populations without concern of significant bias. Copyright © 2015 Elsevier Inc. All rights reserved.

Mixture Item Response Theory-MIMIC Model: Simultaneous Estimation of Differential Item Functioning for Manifest Groups and Latent Classes

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Bilir, Mustafa Kuzey

2009-01-01

This study uses a new psychometric model (mixture item response theory-MIMIC model) that simultaneously estimates differential item functioning (DIF) across manifest groups and latent classes. Current DIF detection methods investigate DIF from only one side, either across manifest groups (e.g., gender, ethnicity, etc.), or across latent classes…

Differential item functioning analysis with ordinal logistic regression techniques. DIFdetect and difwithpar.

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Crane, Paul K; Gibbons, Laura E; Jolley, Lance; van Belle, Gerald

2006-11-01

We present an ordinal logistic regression model for identification of items with differential item functioning (DIF) and apply this model to a Mini-Mental State Examination (MMSE) dataset. We employ item response theory ability estimation in our models. Three nested ordinal logistic regression models are applied to each item. Model testing begins with examination of the statistical significance of the interaction term between ability and the group indicator, consistent with nonuniform DIF. Then we turn our attention to the coefficient of the ability term in models with and without the group term. If including the group term has a marked effect on that coefficient, we declare that it has uniform DIF. We examined DIF related to language of test administration in addition to self-reported race, Hispanic ethnicity, age, years of education, and sex. We used PARSCALE for IRT analyses and STATA for ordinal logistic regression approaches. We used an iterative technique for adjusting IRT ability estimates on the basis of DIF findings. Five items were found to have DIF related to language. These same items also had DIF related to other covariates. The ordinal logistic regression approach to DIF detection, when combined with IRT ability estimates, provides a reasonable alternative for DIF detection. There appear to be several items with significant DIF related to language of test administration in the MMSE. More attention needs to be paid to the specific criteria used to determine whether an item has DIF, not just the technique used to identify DIF.

Differential item functioning of the UWES-17 in South Africa

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Leanne Goliath-Yarde

2011-11-01

Research purpose: This study assesses the Differential Item Functioning (DIF of the Utrecht Work Engagement Scale (UWES-17 for different South African cultural groups in a South African company. Motivation for the study: Organisations are using the UWES-17 more and more in South Africa to assess work engagement. Therefore, research evidence from psychologists or assessment practitioners on its DIF across different cultural groups is necessary. Research design, approach and method: The researchers conducted a Secondary Data Analysis (SDA on the UWES-17 sample (n = 2429 that they obtained from a cross-sectional survey undertaken in a South African Information and Communication Technology (ICT sector company (n = 24 134. Quantitative item data on the UWES-17 scale enabled the authors to address the research question. Main findings: The researchers found uniform and/or non-uniform DIF on five of the vigour items, four of the dedication items and two of the absorption items. This also showed possible Differential Test Functioning (DTF on the vigour and dedication dimensions. Practical/managerial implications: Based on the DIF, the researchers suggested that organisations should not use the UWES-17 comparatively for different cultural groups or employment decisions in South Africa. Contribution/value add: The study provides evidence on DIF and possible DTF for the UWES-17. However, it also raises questions about possible interaction effects that need further investigation.

Item response theory analysis of the life orientation test-revised: age and gender differential item functioning analyses.

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Steca, Patrizia; Monzani, Dario; Greco, Andrea; Chiesi, Francesca; Primi, Caterina

2015-06-01

This study is aimed at testing the measurement properties of the Life Orientation Test-Revised (LOT-R) for the assessment of dispositional optimism by employing item response theory (IRT) analyses. The LOT-R was administered to a large sample of 2,862 Italian adults. First, confirmatory factor analyses demonstrated the theoretical conceptualization of the construct measured by the LOT-R as a single bipolar dimension. Subsequently, IRT analyses for polytomous, ordered response category data were applied to investigate the items' properties. The equivalence of the items across gender and age was assessed by analyzing differential item functioning. Discrimination and severity parameters indicated that all items were able to distinguish people with different levels of optimism and adequately covered the spectrum of the latent trait. Additionally, the LOT-R appears to be gender invariant and, with minor exceptions, age invariant. Results provided evidence that the LOT-R is a reliable and valid measure of dispositional optimism. © The Author(s) 2014.

Effect Size Measures for Differential Item Functioning in a Multidimensional IRT Model

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Suh, Youngsuk

2016-01-01

This study adapted an effect size measure used for studying differential item functioning (DIF) in unidimensional tests and extended the measure to multidimensional tests. Two effect size measures were considered in a multidimensional item response theory model: signed weighted P-difference and unsigned weighted P-difference. The performance of…

Geriatric Anxiety Scale: item response theory analysis, differential item functioning, and creation of a ten-item short form (GAS-10).

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Mueller, Anne E; Segal, Daniel L; Gavett, Brandon; Marty, Meghan A; Yochim, Brian; June, Andrea; Coolidge, Frederick L

2015-07-01

The Geriatric Anxiety Scale (GAS; Segal et al. (Segal, D. L., June, A., Payne, M., Coolidge, F. L. and Yochim, B. (2010). Journal of Anxiety Disorders, 24, 709-714. doi:10.1016/j.janxdis.2010.05.002) is a self-report measure of anxiety that was designed to address unique issues associated with anxiety assessment in older adults. This study is the first to use item response theory (IRT) to examine the psychometric properties of a measure of anxiety in older adults. A large sample of older adults (n = 581; mean age = 72.32 years, SD = 7.64 years, range = 60 to 96 years; 64% women; 88% European American) completed the GAS. IRT properties were examined. The presence of differential item functioning (DIF) or measurement bias by age and sex was assessed, and a ten-item short form of the GAS (called the GAS-10) was created. All GAS items had discrimination parameters of 1.07 or greater. Items from the somatic subscale tended to have lower discrimination parameters than items on the cognitive or affective subscales. Two items were flagged for DIF, but the impact of the DIF was negligible. Women scored significantly higher than men on the GAS and its subscales. Participants in the young-old group (60 to 79 years old) scored significantly higher on the cognitive subscale than participants in the old-old group (80 years old and older). Results from the IRT analyses indicated that the GAS and GAS-10 have strong psychometric properties among older adults. We conclude by discussing implications and future research directions.

Statistical and extra-statistical considerations in differential item functioning analyses

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G. K. Huysamen

2004-10-01

Full Text Available This article briefly describes the main procedures for performing differential item functioning (DIF analyses and points out some of the statistical and extra-statistical implications of these methods. Research findings on the sources of DIF, including those associated with translated tests, are reviewed. As DIF analyses are oblivious of correlations between a test and relevant criteria, the elimination of differentially functioning items does not necessarily improve predictive validity or reduce any predictive bias. The implications of the results of past DIF research for test development in the multilingual and multi-cultural South African society are considered. Opsomming Hierdie artikel beskryf kortliks die hoofprosedures vir die ontleding van differensiële itemfunksionering (DIF en verwys na sommige van die statistiese en buite-statistiese implikasies van hierdie metodes. ’n Oorsig word verskaf van navorsingsbevindings oor die bronne van DIF, insluitend dié by vertaalde toetse. Omdat DIF-ontledings nie die korrelasies tussen ’n toets en relevante kriteria in ag neem nie, sal die verwydering van differensieel-funksionerende items nie noodwendig voorspellingsgeldigheid verbeter of voorspellingsydigheid verminder nie. Die implikasies van vorige DIF-navorsingsbevindings vir toetsontwikkeling in die veeltalige en multikulturele Suid-Afrikaanse gemeenskap word oorweeg.

A more general model for testing measurement invariance and differential item functioning.

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Bauer, Daniel J

2017-09-01

The evaluation of measurement invariance is an important step in establishing the validity and comparability of measurements across individuals. Most commonly, measurement invariance has been examined using 1 of 2 primary latent variable modeling approaches: the multiple groups model or the multiple-indicator multiple-cause (MIMIC) model. Both approaches offer opportunities to detect differential item functioning within multi-item scales, and thereby to test measurement invariance, but both approaches also have significant limitations. The multiple groups model allows 1 to examine the invariance of all model parameters but only across levels of a single categorical individual difference variable (e.g., ethnicity). In contrast, the MIMIC model permits both categorical and continuous individual difference variables (e.g., sex and age) but permits only a subset of the model parameters to vary as a function of these characteristics. The current article argues that moderated nonlinear factor analysis (MNLFA) constitutes an alternative, more flexible model for evaluating measurement invariance and differential item functioning. We show that the MNLFA subsumes and combines the strengths of the multiple group and MIMIC models, allowing for a full and simultaneous assessment of measurement invariance and differential item functioning across multiple categorical and/or continuous individual difference variables. The relationships between the MNLFA model and the multiple groups and MIMIC models are shown mathematically and via an empirical demonstration. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Detection of differential item functioning using Lagrange multiplier tests

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Glas, Cornelis A.W.

1998-01-01

Abstract: In the present paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or Rao’s efficient score test. The test is presented in the framework of a number of IRT models such as the Rasch model, the OPLM, the 2-parameter logistic model, the

Examining Multiple Sources of Differential Item Functioning on the Clinician & Group CAHPS® Survey

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Rodriguez, Hector P; Crane, Paul K

2011-01-01

Objective To evaluate psychometric properties of a widely used patient experience survey. Data Sources English-language responses to the Clinician & Group Consumer Assessment of Healthcare Providers and Systems (CG-CAHPS®) survey (n = 12,244) from a 2008 quality improvement initiative involving eight southern California medical groups. Methods We used an iterative hybrid ordinal logistic regression/item response theory differential item functioning (DIF) algorithm to identify items with DIF related to patient sociodemographic characteristics, duration of the physician–patient relationship, number of physician visits, and self-rated physical and mental health. We accounted for all sources of DIF and determined its cumulative impact. Principal Findings The upper end of the CG-CAHPS® performance range is measured with low precision. With sensitive settings, some items were found to have DIF. However, overall DIF impact was negligible, as 0.14 percent of participants had salient DIF impact. Latinos who spoke predominantly English at home had the highest prevalence of salient DIF impact at 0.26 percent. Conclusions The CG-CAHPS® functions similarly across commercially insured respondents from diverse backgrounds. Consequently, previously documented racial and ethnic group differences likely reflect true differences rather than measurement bias. The impact of low precision at the upper end of the scale should be clarified. PMID:22092021

Differential Item Functioning Analysis of the Mental, Emotional, and Bodily Toughness Inventory

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Gao, Yong; Mack, Mick G.; Ragan, Moira A.; Ragan, Brian

2012-01-01

In this study the authors used differential item functioning analysis to examine if there were items in the Mental, Emotional, and Bodily Toughness Inventory functioning differently across gender and athletic membership. A total of 444 male (56.3%) and female (43.7%) participants (30.9% athletes and 69.1% non-athletes) responded to the Mental,…

Identifying predictors of physics item difficulty: A linear regression approach

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Mesic, Vanes; Muratovic, Hasnija

2011-06-01

Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge

Identifying predictors of physics item difficulty: A linear regression approach

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Hasnija Muratovic

2011-06-01

Full Text Available Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal

Does Gender-Specific Differential Item Functioning Affect the Structure in Vocational Interest Inventories?

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Beinicke, Andrea; Pässler, Katja; Hell, Benedikt

2014-01-01

The study investigates consequences of eliminating items showing gender-specific differential item functioning (DIF) on the psychometric structure of a standard RIASEC interest inventory. Holland's hexagonal model was tested for structural invariance using a confirmatory methodological approach (confirmatory factor analysis and randomization…

Differential Weighting of Items to Improve University Admission Test Validity

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Eduardo Backhoff Escudero

2001-05-01

Full Text Available This paper gives an evaluation of different ways to increase university admission test criterion-related validity, by differentially weighting test items. We compared four methods of weighting multiple-choice items of the Basic Skills and Knowledge Examination (EXHCOBA: (1 punishing incorrect responses by a constant factor, (2 weighting incorrect responses, considering the levels of error, (3 weighting correct responses, considering the item’s difficulty, based on the Classic Measurement Theory, and (4 weighting correct responses, considering the item’s difficulty, based on the Item Response Theory. Results show that none of these methods increased the instrument’s predictive validity, although they did improve its concurrent validity. It was concluded that it is appropriate to score the test by simply adding up correct responses.

Identify, Organize, and Retrieve Items Using Zotero

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Clark, Brian; Stierman, John

2009-01-01

Librarians build collections. To do this they use tools that help them identify, organize, and retrieve items for the collection. Zotero (zoh-TAIR-oh) is such a tool that helps the user build a library of useful books, articles, web sites, blogs, etc., discovered while surfing online. A visit to Zotero's homepage, www.zotero.org, shows a number of…

Use of differential item functioning analysis to assess the equivalence of translations of a questionnaire

NARCIS (Netherlands)

Petersen, Morten Aa; Groenvold, Mogens; Bjorner, Jakob B.; Aaronson, Neil; Conroy, Thierry; Cull, Ann; Fayers, Peter; Hjermstad, Marianne; Sprangers, Mirjam; Sullivan, Marianne

2003-01-01

In cross-national comparisons based on questionnaires, accurate translations are necessary to obtain valid results. Differential item functioning (DIF) analysis can be used to test whether translations of items in multi-item scales are equivalent to the original. In data from 10,815 respondents

Stepwise Analysis of Differential Item Functioning Based on Multiple-Group Partial Credit Model.

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Muraki, Eiji

1999-01-01

Extended an Item Response Theory (IRT) method for detection of differential item functioning to the partial credit model and applied the method to simulated data using a stepwise procedure. Then applied the stepwise DIF analysis based on the multiple-group partial credit model to writing trend data from the National Assessment of Educational…

Effects of Differential Item Functioning on Examinees' Test Performance and Reliability of Test

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Lee, Yi-Hsuan; Zhang, Jinming

2017-01-01

Simulations were conducted to examine the effect of differential item functioning (DIF) on measurement consequences such as total scores, item response theory (IRT) ability estimates, and test reliability in terms of the ratio of true-score variance to observed-score variance and the standard error of estimation for the IRT ability parameter. The…

Assessment of Differential Item Functioning in the Experiences of Discrimination Index

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Cunningham, Timothy J.; Berkman, Lisa F.; Gortmaker, Steven L.; Kiefe, Catarina I.; Jacobs, David R.; Seeman, Teresa E.; Kawachi, Ichiro

2011-01-01

The psychometric properties of instruments used to measure self-reported experiences of discrimination in epidemiologic studies are rarely assessed, especially regarding construct validity. The authors used 2000–2001 data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study to examine differential item functioning (DIF) in 2 versions of the Experiences of Discrimination (EOD) Index, an index measuring self-reported experiences of racial/ethnic and gender discrimination. DIF may confound interpretation of subgroup differences. Large DIF was observed for 2 of 7 racial/ethnic discrimination items: White participants reported more racial/ethnic discrimination for the “at school” item, and black participants reported more racial/ethnic discrimination for the “getting housing” item. The large DIF by race/ethnicity in the index for racial/ethnic discrimination probably reflects item impact and is the result of valid group differences between blacks and whites regarding their respective experiences of discrimination. The authors also observed large DIF by race/ethnicity for 3 of 7 gender discrimination items. This is more likely to have been due to item bias. Users of the EOD Index must consider the advantages and disadvantages of DIF adjustment (omitting items, constructing separate measures, and retaining items). The EOD Index has substantial usefulness as an instrument that can assess self-reported experiences of discrimination. PMID:22038104

Detection of Differential Item Functioning with Nonlinear Regression: A Non-IRT Approach Accounting for Guessing

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Drabinová, Adéla; Martinková, Patrícia

2017-01-01

In this article we present a general approach not relying on item response theory models (non-IRT) to detect differential item functioning (DIF) in dichotomous items with presence of guessing. The proposed nonlinear regression (NLR) procedure for DIF detection is an extension of method based on logistic regression. As a non-IRT approach, NLR can…

Differential item functioning analysis of the Vanderbilt Expertise Test for cars.

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Lee, Woo-Yeol; Cho, Sun-Joo; McGugin, Rankin W; Van Gulick, Ana Beth; Gauthier, Isabel

2015-01-01

The Vanderbilt Expertise Test for cars (VETcar) is a test of visual learning for contemporary car models. We used item response theory to assess the VETcar and in particular used differential item functioning (DIF) analysis to ask if the test functions the same way in laboratory versus online settings and for different groups based on age and gender. An exploratory factor analysis found evidence of multidimensionality in the VETcar, although a single dimension was deemed sufficient to capture the recognition ability measured by the test. We selected a unidimensional three-parameter logistic item response model to examine item characteristics and subject abilities. The VETcar had satisfactory internal consistency. A substantial number of items showed DIF at a medium effect size for test setting and for age group, whereas gender DIF was negligible. Because online subjects were on average older than those tested in the lab, we focused on the age groups to conduct a multigroup item response theory analysis. This revealed that most items on the test favored the younger group. DIF could be more the rule than the exception when measuring performance with familiar object categories, therefore posing a challenge for the measurement of either domain-general visual abilities or category-specific knowledge.

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression

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Scott, Neil W.; Fayers, Peter M.; Aaronson, Neil K.

2010-01-01

Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise...

The MIMIC Method with Scale Purification for Detecting Differential Item Functioning

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Wang, Wen-Chung; Shih, Ching-Lin; Yang, Chih-Chien

2009-01-01

This study implements a scale purification procedure onto the standard MIMIC method for differential item functioning (DIF) detection and assesses its performance through a series of simulations. It is found that the MIMIC method with scale purification (denoted as M-SP) outperforms the standard MIMIC method (denoted as M-ST) in controlling…

The practical impact of differential item functioning analyses in a health-related quality of life instrument

DEFF Research Database (Denmark)

Scott, Neil W; Fayers, Peter M; Aaronson, Neil K

2009-01-01

Differential item functioning (DIF) analyses are commonly used to evaluate health-related quality of life (HRQoL) instruments. There is, however, a lack of consensus as to how to assess the practical impact of statistically significant DIF results.......Differential item functioning (DIF) analyses are commonly used to evaluate health-related quality of life (HRQoL) instruments. There is, however, a lack of consensus as to how to assess the practical impact of statistically significant DIF results....

Why Consumers Misattribute Sponsorships to Non-Sponsor Brands: Differential Roles of Item and Relational Communications.

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Weeks, Clinton S; Humphreys, Michael S; Cornwell, T Bettina

2018-02-01

Brands engaged in sponsorship of events commonly have objectives that depend on consumer memory for the sponsor-event relationship (e.g., sponsorship awareness). Consumers however, often misattribute sponsorships to nonsponsor competitor brands, indicating erroneous memory for these relationships. The current research uses an item and relational memory framework to reveal sponsor brands may inadvertently foster this misattribution when they communicate relational linkages to events. Effects can be explained via differential roles of communicating item information (information that supports processing item distinctiveness) versus relational information (information that supports processing relationships among items) in contributing to memory outcomes. Experiment 1 uses event-cued brand recall to show that correct memory retrieval is best supported by communicating relational information when sponsorship relationships are not obvious (low congruence). In contrast, correct retrieval is best supported by communicating item information when relationships are obvious (high congruence). Experiment 2 uses brand-cued event recall to show that, against conventional marketing recommendations, relational information increases misattribution, whereas item information guards against misattribution. Results suggest sponsor brands must distinguish between item and relational communications to enhance correct retrieval and limit misattribution. Methodologically, the work shows that choice of cueing direction is critical in differentially revealing patterns of correct and incorrect retrieval with pair relationships. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Overcoming the effects of differential skewness of test items in scale construction

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Johann M. Schepers

2004-10-01

Full Text Available The principal objective of the study was to develop a procedure for overcoming the effects of differential skewness of test items in scale construction. It was shown that the degree of skewness of test items places an upper limit on the correlations between the items, regardless of the contents of the items. If the items are ordered in terms of skewness the resulting inter correlation matrix forms a simplex or a pseudo simplex. Factoring such a matrix results in a multiplicity of factors, most of which are artifacts. A procedure for overcoming this problem was demonstrated with items from the Locus of Control Inventory (Schepers, 1995. The analysis was based on a sample of 1662 first year university students. Opsomming Die hoofdoel van die studie was om ’n prosedure te ontwikkel om die gevolge van differensiële skeefheid van toetsitems, in skaalkonstruksie, teen te werk. Daar is getoon dat die graad van skeefheid van toetsitems ’n boonste grens plaas op die korrelasies tussen die items ongeag die inhoud daarvan. Indien die items gerangskik word volgens graad van skeefheid, sal die interkorrelasiematriks van die items ’n simpleks of pseudosimpleks vorm. Indien so ’n matriks aan faktorontleding onderwerp word, lei dit tot ’n veelheid van faktore waarvan die meerderheid artefakte is. ’n Prosedure om hierdie probleem te bowe te kom, is gedemonstreer met behulp van die items van die Lokus van Beheer-vraelys (Schepers, 1995. Die ontledings is op ’n steekproef van 1662 eerstejaaruniversiteitstudente gebaseer.

Analysis of differential item functioning in the depression item bank from the Patient Reported Outcome Measurement Information System (PROMIS: An item response theory approach

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JOSEPH P. EIMICKE

2009-06-01

Full Text Available The aims of this paper are to present findings related to differential item functioning (DIF in the Patient Reported Outcome Measurement Information System (PROMIS depression item bank, and to discuss potential threats to the validity of results from studies of DIF. The 32 depression items studied were modified from several widely used instruments. DIF analyses of gender, age and education were performed using a sample of 735 individuals recruited by a survey polling firm. DIF hypotheses were generated by asking content experts to indicate whether or not they expected DIF to be present, and the direction of the DIF with respect to the studied comparison groups. Primary analyses were conducted using the graded item response model (for polytomous, ordered response category data with likelihood ratio tests of DIF, accompanied by magnitude measures. Sensitivity analyses were performed using other item response models and approaches to DIF detection. Despite some caveats, the items that are recommended for exclusion or for separate calibration were "I felt like crying" and "I had trouble enjoying things that I used to enjoy." The item, "I felt I had no energy," was also flagged as evidencing DIF, and recommended for additional review. On the one hand, false DIF detection (Type 1 error was controlled to the extent possible by ensuring model fit and purification. On the other hand, power for DIF detection might have been compromised by several factors, including sparse data and small sample sizes. Nonetheless, practical and not just statistical significance should be considered. In this case the overall magnitude and impact of DIF was small for the groups studied, although impact was relatively large for some individuals.

Detection of Differential Item Functioning with Nonlinear Regression: A Non-IRT Approach Accounting for Guessing

Czech Academy of Sciences Publication Activity Database

Drabinová, Adéla; Martinková, Patrícia

2017-01-01

Roč. 54, č. 4 (2017), s. 498-517 ISSN 0022-0655 R&D Projects: GA ČR GJ15-15856Y Institutional support: RVO:67985807 Keywords : differential item functioning * non-linear regression * logistic regression * item response theory Subject RIV: AM - Education OBOR OECD: Statistics and probability Impact factor: 0.979, year: 2016

Re-evaluating a vision-related quality of life questionnaire with item response theory (IRT and differential item functioning (DIF analyses

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Knol Dirk L

2011-09-01

Full Text Available Abstract Background For the Low Vision Quality Of Life questionnaire (LVQOL it is unknown whether the psychometric properties are satisfactory when an item response theory (IRT perspective is considered. This study evaluates some essential psychometric properties of the LVQOL questionnaire in an IRT model, and investigates differential item functioning (DIF. Methods Cross-sectional data were used from an observational study among visually-impaired patients (n = 296. Calibration was performed for every dimension of the LVQOL in the graded response model. Item goodness-of-fit was assessed with the S-X2-test. DIF was assessed on relevant background variables (i.e. age, gender, visual acuity, eye condition, rehabilitation type and administration type with likelihood-ratio tests for DIF. The magnitude of DIF was interpreted by assessing the largest difference in expected scores between subgroups. Measurement precision was assessed by presenting test information curves; reliability with the index of subject separation. Results All items of the LVQOL dimensions fitted the model. There was significant DIF on several items. For two items the maximum difference between expected scores exceeded one point, and DIF was found on multiple relevant background variables. Item 1 'Vision in general' from the "Adjustment" dimension and item 24 'Using tools' from the "Reading and fine work" dimension were removed. Test information was highest for the "Reading and fine work" dimension. Indices for subject separation ranged from 0.83 to 0.94. Conclusions The items of the LVQOL showed satisfactory item fit to the graded response model; however, two items were removed because of DIF. The adapted LVQOL with 21 items is DIF-free and therefore seems highly appropriate for use in heterogeneous populations of visually impaired patients.

Measurement equivalence and differential item functioning in family psychology.

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Bingenheimer, Jeffrey B; Raudenbush, Stephen W; Leventhal, Tama; Brooks-Gunn, Jeanne

2005-09-01

Several hypotheses in family psychology involve comparisons of sociocultural groups. Yet the potential for cross-cultural inequivalence in widely used psychological measurement instruments threatens the validity of inferences about group differences. Methods for dealing with these issues have been developed via the framework of item response theory. These methods deal with an important type of measurement inequivalence, called differential item functioning (DIF). The authors introduce DIF analytic methods, linking them to a well-established framework for conceptualizing cross-cultural measurement equivalence in psychology (C.H. Hui and H.C. Triandis, 1985). They illustrate the use of DIF methods using data from the Project on Human Development in Chicago Neighborhoods (PHDCN). Focusing on the Caregiver Warmth and Environmental Organization scales from the PHDCN's adaptation of the Home Observation for Measurement of the Environment Inventory, the authors obtain results that exemplify the range of outcomes that may result when these methods are applied to psychological measurement instruments. (c) 2005 APA, all rights reserved

Individuals with knee impairments identify items in need of clarification in the Patient Reported Outcomes Measurement Information System (PROMIS®) pain interference and physical function item banks - a qualitative study.

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Lynch, Andrew D; Dodds, Nathan E; Yu, Lan; Pilkonis, Paul A; Irrgang, James J

2016-05-11

The content and wording of the Patient Reported Outcome Measurement Information System (PROMIS) Physical Function and Pain Interference item banks have not been qualitatively assessed by individuals with knee joint impairments. The purpose of this investigation was to identify items in the PROMIS Physical Function and Pain Interference Item Banks that are irrelevant, unclear, or otherwise difficult to respond to for individuals with impairment of the knee and to suggest modifications based on cognitive interviews. Twenty-nine individuals with knee joint impairments qualitatively assessed items in the Pain Interference and Physical Function Item Banks in a mixed-methods cognitive interview. Field notes were analyzed to identify themes and frequency counts were calculated to identify items not relevant to individuals with knee joint impairments. Issues with clarity were identified in 23 items in the Physical Function Item Bank, resulting in the creation of 43 new or modified items, typically changing words within the item to be clearer. Interpretation issues included whether or not the knee joint played a significant role in overall health and age/gender differences in items. One quarter of the original items (31 of 124) in the Physical Function Item Bank were identified as irrelevant to the knee joint. All 41 items in the Pain Interference Item Bank were identified as clear, although individuals without significant pain substituted other symptoms which interfered with their life. The Physical Function Item Bank would benefit from additional items that are relevant to individuals with knee joint impairments and, by extension, to other lower extremity impairments. Several issues in clarity were identified that are likely to be present in other patient cohorts as well.

Secondary Psychometric Examination of the Dimensional Obsessive-Compulsive Scale: Classical Testing, Item Response Theory, and Differential Item Functioning.

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Thibodeau, Michel A; Leonard, Rachel C; Abramowitz, Jonathan S; Riemann, Bradley C

2015-12-01

The Dimensional Obsessive-Compulsive Scale (DOCS) is a promising measure of obsessive-compulsive disorder (OCD) symptoms but has received minimal psychometric attention. We evaluated the utility and reliability of DOCS scores. The study included 832 students and 300 patients with OCD. Confirmatory factor analysis supported the originally proposed four-factor structure. DOCS total and subscale scores exhibited good to excellent internal consistency in both samples (α = .82 to α = .96). Patient DOCS total scores reduced substantially during treatment (t = 16.01, d = 1.02). DOCS total scores discriminated between students and patients (sensitivity = 0.76, 1 - specificity = 0.23). The measure did not exhibit gender-based differential item functioning as tested by Mantel-Haenszel chi-square tests. Expected response options for each item were plotted as a function of item response theory and demonstrated that DOCS scores incrementally discriminate OCD symptoms ranging from low to extremely high severity. Incremental differences in DOCS scores appear to represent unbiased and reliable differences in true OCD symptom severity. © The Author(s) 2014.

Gender Invariance of the Gambling Behavior Scale for Adolescents (GBS-A): An Analysis of Differential Item Functioning Using Item Response Theory.

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Donati, Maria Anna; Chiesi, Francesca; Izzo, Viola A; Primi, Caterina

2017-01-01

As there is a lack of evidence attesting the equivalent item functioning across genders for the most employed instruments used to measure pathological gambling in adolescence, the present study was aimed to test the gender invariance of the Gambling Behavior Scale for Adolescents (GBS-A), a new measurement tool to assess the severity of Gambling Disorder (GD) in adolescents. The equivalence of the items across genders was assessed by analyzing Differential Item Functioning within an Item Response Theory framework. The GBS-A was administered to 1,723 adolescents, and the graded response model was employed. The results attested the measurement equivalence of the GBS-A when administered to male and female adolescent gamblers. Overall, findings provided evidence that the GBS-A is an effective measurement tool of the severity of GD in male and female adolescents and that the scale was unbiased and able to relieve truly gender differences. As such, the GBS-A can be profitably used in educational interventions and clinical treatments with young people.

Exploring differential item functioning (DIF) with the Rasch model: A comparison of gender differences on eighth-grade science items in the United States and Spain

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Calvert, Tasha

Despite the attention that has been given to gender and science, boys continue to outperform girls in science achievement, particularly by the end of secondary school. Because it is unclear whether gender differences have narrowed over time (Leder, 1992; Willingham & Cole, 1997), it is important to continue a line of inquiry into the nature of gender differences, specifically at the international level. The purpose of this study was to investigate gender differences in science achievement across two countries: United States and Spain. A secondary purpose was to demonstrate an alternative method for exploring gender differences based on the many-faceted Rasch model (1980). A secondary analysis of the data from the Third International Mathematics and Science Study (TIMSS) was used to examine the relationship between gender DIF (differential item functioning) and item characteristics (item type, content, and performance expectation) across both countries. Nationally representative samples of eighth grade students in the United States and Spain who participated in TIMSS were analyzed to answer the research questions in this study. In both countries, girls showed an advantage over boys on life science items and most extended response items, whereas boys, by and large, had an advantage on earth science, physics, and chemistry items. However, even within areas that favored boys, such as physics, there were items that were differentially easier for girls. In general, patterns in gender differences were similar across both countries although there were a few differences between the countries on individual items. It was concluded that simply looking at mean differences does not provide an adequate understanding of the nature of gender differences in science achievement.

Parent Ratings of ADHD Symptoms: Generalized Partial Credit Model Analysis of Differential Item Functioning across Gender

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Gomez, Rapson

2012-01-01

Objective: Generalized partial credit model, which is based on item response theory (IRT), was used to test differential item functioning (DIF) for the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.), inattention (IA), and hyperactivity/impulsivity (HI) symptoms across boys and girls. Method: To accomplish this, parents completed…

Determination of a Differential Item Functioning Procedure Using the Hierarchical Generalized Linear Model

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Tülin Acar

2012-01-01

Full Text Available The aim of this research is to compare the result of the differential item functioning (DIF determining with hierarchical generalized linear model (HGLM technique and the results of the DIF determining with logistic regression (LR and item response theory–likelihood ratio (IRT-LR techniques on the test items. For this reason, first in this research, it is determined whether the students encounter DIF with HGLM, LR, and IRT-LR techniques according to socioeconomic status (SES, in the Turkish, Social Sciences, and Science subtest items of the Secondary School Institutions Examination. When inspecting the correlations among the techniques in terms of determining the items having DIF, it was discovered that there was significant correlation between the results of IRT-LR and LR techniques in all subtests; merely in Science subtest, the results of the correlation between HGLM and IRT-LR techniques were found significant. DIF applications can be made on test items with other DIF analysis techniques that were not taken to the scope of this research. The analysis results, which were determined by using the DIF techniques in different sample sizes, can be compared.

Racial differences in hypertension knowledge: effects of differential item functioning.

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Ayotte, Brian J; Trivedi, Ranak; Bosworth, Hayden B

2009-01-01

Health-related knowledge is an important component in the self-management of chronic illnesses. The objective of this study was to more accurately assess racial differences in hypertension knowledge by using a latent variable modeling approach that controlled for sociodemographic factors and accounted for measurement issues in the assessment of hypertension knowledge. Cross-sectional data from 1,177 participants (45% African American; 35% female) were analyzed using a multiple indicator multiple causes (MIMIC) modeling approach. Available sociodemographic data included race, education, sex, financial status, and age. All participants completed six items on a hypertension knowledge questionnaire. Overall, the final model suggested that females, Whites, and patients with at least a high school diploma had higher latent knowledge scores than males, African Americans, and patients with less than a high school diploma, respectively. The model also detected differential item functioning (DIF) based on race for two of the items. Specifically, the error rate for African Americans was lower than would be expected given the lower level of latent knowledge on the items, on the questions related to: (a) the association between high blood pressure and kidney disease, and (b) the increased risk African Americans have for developing hypertension. Not accounting for DIF resulted in the difference between Whites and African Americans to be underestimated. These results are discussed in the context of the need for careful measurement of health-related constructs, and how measurement-related issues can result in an inaccurate estimation of racial differences in hypertension knowledge.

A Systematic Approach to Identify Promising New Items for Small to Medium Enterprises: A Case Study

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Sukjae Jeong

2016-11-01

Full Text Available Despite the growing importance of identifying new business items for small and medium enterprises (SMEs, most previous studies focus on conglomerates. The paucity of empirical studies has also led to limited real-life applications. Hence, this study proposes a systematic approach to find new business items (NBIs that help the prospective SMEs develop, evaluate, and select viable business items to survive the competitive environment. The proposed approach comprises two stages: (1 the classification of diversification of SMEs; and (2 the searching and screening of business items. In the first stage, SMEs are allocated to five groups, based on their internal technological competency and external market conditions. In the second stage, based on the types of SMEs identified in the first stage, a set of alternative business items is derived by combining the results of portfolio analysis and benchmarking analysis. After deriving new business items, a market and technology-driven matrix analysis is utilized to screen suitable business items, and the Bruce Merrifield-Ohe (BMO method is used to categorize and identify prospective items based on market attractiveness and internal capability. To illustrate the applicability of the proposed approach, a case study is presented.

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression

DEFF Research Database (Denmark)

Scott, Neil W; Fayers, Peter M; Aaronson, Neil K

2010-01-01

Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise ...... when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application....

Differential items functioning to assess aggressiveness in college students / Funcionamento diferencial de itens para avaliar a agressividade de universitários

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Fermino Fernandes Sisto

2008-01-01

Full Text Available In this research evidences of construct validity were searched analyzing the differential functioning items related to aggressiveness. The participants were 445 college students of both genders, attending the courses of Engineering, Computing and Psychology. The scale of aggressiveness composed by 81 items was collectively applied, in the classroom, to the students who consented to participate in the study. The items of the instrument were studied by means of the Rasch model. Twenty-eight items presented differential functioning item, 15 were characterized as typical for females and 13 for males. The reliability coefficients were 0.99 to the items and 0.86 to the persons. It was concluded that the aggressiveness can be measured separately on the basis of gender.

Power and Sample Size Calculations for Logistic Regression Tests for Differential Item Functioning

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Li, Zhushan

2014-01-01

Logistic regression is a popular method for detecting uniform and nonuniform differential item functioning (DIF) effects. Theoretical formulas for the power and sample size calculations are derived for likelihood ratio tests and Wald tests based on the asymptotic distribution of the maximum likelihood estimators for the logistic regression model.…

The Dif Identification in Constructed Response Items Using Partial Credit Model

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Heri Retnawati

2017-10-01

Full Text Available The study was to identify the load, the type and the significance of differential item functioning (DIF in constructed response item using the partial credit model (PCM. The data in the study were the students’ instruments and the students’ responses toward the PISA-like test items that had been completed by 386 ninth grade students and 460 tenth grade students who had been about 15 years old in the Province of Yogyakarta Special Region in Indonesia. The analysis toward the item characteristics through the student categorization based on their class was conducted toward the PCM using CONQUEST software. Furthermore, by applying these items characteristics, the researcher draw the category response function (CRF graphic in order to identify whether the type of DIF content had been in uniform or non-uniform. The significance of DIF was identified by comparing the discrepancy between the difficulty level parameter and the error in the CONQUEST output results. The results of the analysis showed that from 18 items that had been analyzed there were 4 items which had not been identified load DIF, there were 5 items that had been identified containing DIF but not statistically significant and there were 9 items that had been identified containing DIF significantly. The causes of items containing DIF were discussed.

Consolidation differentially modulates schema effects on memory for items and associations.

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van Kesteren, Marlieke T R; Rijpkema, Mark; Ruiter, Dirk J; Fernández, Guillén

2013-01-01

Newly learned information that is congruent with a preexisting schema is often better remembered than information that is incongruent. This schema effect on memory has previously been associated to more efficient encoding and consolidation mechanisms. However, this effect is not always consistently supported in the literature, with differential schema effects reported for different types of memory, different retrieval cues, and the possibility of time-dependent effects related to consolidation processes. To examine these effects more directly, we tested participants on two different types of memory (item recognition and associative memory) for newly encoded visuo-tactile associations at different study-test intervals, thus probing memory retrieval accuracy for schema-congruent and schema-incongruent items and associations at different time points (t = 0, t = 20, and t = 48 hours) after encoding. Results show that the schema effect on visual item recognition only arises after consolidation, while the schema effect on associative memory is already apparent immediately after encoding, persisting, but getting smaller over time. These findings give further insight into different factors influencing the schema effect on memory, and can inform future schema experiments by illustrating the value of considering effects of memory type and consolidation on schema-modulated retrieval.

Consolidation differentially modulates schema effects on memory for items and associations.

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Marlieke T R van Kesteren

Full Text Available Newly learned information that is congruent with a preexisting schema is often better remembered than information that is incongruent. This schema effect on memory has previously been associated to more efficient encoding and consolidation mechanisms. However, this effect is not always consistently supported in the literature, with differential schema effects reported for different types of memory, different retrieval cues, and the possibility of time-dependent effects related to consolidation processes. To examine these effects more directly, we tested participants on two different types of memory (item recognition and associative memory for newly encoded visuo-tactile associations at different study-test intervals, thus probing memory retrieval accuracy for schema-congruent and schema-incongruent items and associations at different time points (t = 0, t = 20, and t = 48 hours after encoding. Results show that the schema effect on visual item recognition only arises after consolidation, while the schema effect on associative memory is already apparent immediately after encoding, persisting, but getting smaller over time. These findings give further insight into different factors influencing the schema effect on memory, and can inform future schema experiments by illustrating the value of considering effects of memory type and consolidation on schema-modulated retrieval.

The Dif Identification in Constructed Response Items Using Partial Credit Model

OpenAIRE

Heri Retnawati

2017-01-01

The study was to identify the load, the type and the significance of differential item functioning (DIF) in constructed response item using the partial credit model (PCM). The data in the study were the students’ instruments and the students’ responses toward the PISA-like test items that had been completed by 386 ninth grade students and 460 tenth grade students who had been about 15 years old in the Province of Yogyakarta Special Region in Indonesia. The analysis toward the item characteris...

Brief Report: Checklist for Autism Spectrum Disorder--Most Discriminating Items for Diagnosing Autism

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Mayes, Susan D.

2018-01-01

The smallest subset of items from the 30-item Checklist for Autism Spectrum Disorder (CASD) that differentiated 607 referred children (3-17 years) with and without autism with 100% accuracy was identified. This 6-item subset (CASD-Short Form) was cross-validated on an independent sample of 397 referred children (1-18 years) with and without autism…

Detection of Differential Item Functioning on the Kirton Adaption-Innovation Inventory Using Multiple-Group Mean and Covariance Structure Analyses.

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Chan, David

2000-01-01

Demonstrates how the mean and covariance structure analysis model of D. Sorbom (1974) can be used to detect uniform and nonuniform differential item functioning (DIF) on polytomous ordered response items assumed to approximate a continuous scale. Uses results from 773 civil service employees administered the Kirton Adaption-Innovation Inventory…

Standard Errors for National Trends in International Large-Scale Assessments in the Case of Cross-National Differential Item Functioning

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Sachse, Karoline A.; Haag, Nicole

2017-01-01

Standard errors computed according to the operational practices of international large-scale assessment studies such as the Programme for International Student Assessment's (PISA) or the Trends in International Mathematics and Science Study (TIMSS) may be biased when cross-national differential item functioning (DIF) and item parameter drift are…

An Examination of Differential Item Functioning on the Vanderbilt Assessment of Leadership in Education

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Polikoff, Morgan S.; May, Henry; Porter, Andrew C.; Elliott, Stephen N.; Goldring, Ellen; Murphy, Joseph

2009-01-01

The Vanderbilt Assessment of Leadership in Education is a 360-degree assessment of the effectiveness of principals' learning-centered leadership behaviors. In this report, we present results from a differential item functioning (DIF) study of the assessment. Using data from a national field trial, we searched for evidence of DIF on school level,…

The MIMIC Model as a Tool for Differential Bundle Functioning Detection

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Finch, W. Holmes

2012-01-01

Increasingly, researchers interested in identifying potentially biased test items are encouraged to use a confirmatory, rather than exploratory, approach. One such method for confirmatory testing is rooted in differential bundle functioning (DBF), where hypotheses regarding potential differential item functioning (DIF) for sets of items (bundles)…

Toward a More Responsive Consumable Materiel Supply Chain: Leveraging New Metrics to Identify and Classify Items of Concern

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2016-06-01

MATERIEL SUPPLY CHAIN: LEVERAGING NEW METRICS TO IDENTIFY AND CLASSIFY ITEMS OF CONCERN by Andrew R. Haley June 2016 Thesis Advisor: Robert...IDENTIFY AND CLASSIFY ITEMS OF CONCERN 5. FUNDING NUMBERS 6. AUTHOR(S) Andrew R. Haley 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval...Supply Systems Command (NAVSUP), logistics, inventory, consumable, NSNs at Risk, Bad Actors, Bad Actors with Trend, items of concern , customer time

Psychometric evaluation of Persian Nomophobia Questionnaire: Differential item functioning and measurement invariance across gender.

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Lin, Chung-Ying; Griffiths, Mark D; Pakpour, Amir H

2018-03-01

Background and aims Research examining problematic mobile phone use has increased markedly over the past 5 years and has been related to "no mobile phone phobia" (so-called nomophobia). The 20-item Nomophobia Questionnaire (NMP-Q) is the only instrument that assesses nomophobia with an underlying theoretical structure and robust psychometric testing. This study aimed to confirm the construct validity of the Persian NMP-Q using Rasch and confirmatory factor analysis (CFA) models. Methods After ensuring the linguistic validity, Rasch models were used to examine the unidimensionality of each Persian NMP-Q factor among 3,216 Iranian adolescents and CFAs were used to confirm its four-factor structure. Differential item functioning (DIF) and multigroup CFA were used to examine whether males and females interpreted the NMP-Q similarly, including item content and NMP-Q structure. Results Each factor was unidimensional according to the Rach findings, and the four-factor structure was supported by CFA. Two items did not quite fit the Rasch models (Item 14: "I would be nervous because I could not know if someone had tried to get a hold of me;" Item 9: "If I could not check my smartphone for a while, I would feel a desire to check it"). No DIF items were found across gender and measurement invariance was supported in multigroup CFA across gender. Conclusions Due to the satisfactory psychometric properties, it is concluded that the Persian NMP-Q can be used to assess nomophobia among adolescents. Moreover, NMP-Q users may compare its scores between genders in the knowledge that there are no score differences contributed by different understandings of NMP-Q items.

Identifying Sources of Scientific Knowledge: classifying non-source items in the WoS

Energy Technology Data Exchange (ETDEWEB)

Calero-Medina, C.M.

2016-07-01

The sources of scientific knowledge can be tracked using the references in scientific publications. For instance, the publications from the scientific journals covered by the Web of Science database (WoS) contain references to publications for which an indexed source record exist in the WoS (source items) or to references for which an indexed source record does not exist in the WoS (non-source items). The classification of the non-source items is the main objective of the work in progress presented here. Some other scholars have classified and identified non-source items with different purposes (e.g. Butler & Visser (2006); Liseé, Larivière & Archambault (2008); Nerderhof, van Leeuwen & van Raan (2010); Hicks & Wang (2013); Boyack & Klavans (2014)). But these studies are focused in specific source types, fields or set of papers. The work presented here is much broader in terms of the number of publications, source types and fields. (Author)

Quality of life in infants and children with atopic dermatitis: Addressing issues of differential item functioning across countries in multinational clinical trials

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Tennant Alan

2007-07-01

Full Text Available Abstract Background A previous study had identified 45 items assessing the impact of atopic dermatitis (AD on the whole family. From these it was intended to develop two separate scales, one assessing impact on carers and the other determining the effect on the child. Methods The 45 items were included in three clinical trials designed to test the efficacy of a new topical treatment (pimecrolimus, Elidel cream 1% in the treatment of AD in infants and children and in validation studies in the UK, US, Germany, France and the Netherlands. Rasch analyses were undertaken to determine whether an internationally valid, unidimensional scale could be developed that would inform on the direct impact of AD on the child. Results Rasch analyses applied to the data from the trials indicated that the draft measure consisted of two scales, one assessing the QoL of the carer and the other (consisting of 12 items measuring the impact of AD on the child. Three of the 12 potential items failed to fit the measurement model in Europe and five in the US. In addition, four items exhibiting differential item functioning (DIF by country were identified. After removing the misfitting items and controlling for DIF it was possible to derive a scale; The Childhood Impact of Atopic Dermatitis (CIAD with good item fit for each trial analysis. Analysis of the validation data from each of the different countries confirmed that the CIAD had adequate internal consistency, reproducibility and construct validity. The CIAD demonstrated the benefits of treatment with Elidel over placebo in the European trial. A similar (non-significant trend was found for the US trials. Conclusion The study represents a novel method of dealing with the problem of DIF associated with different cultures. Such problems are likely to arise in any multinational study involving patient-reported outcome measures, as items in the scales are likely to be valued differently in different cultures. However, where

Differential Item Functioning of the Psychological Domain of the Menopause Rating Scale

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Portela-Buelvas, Katherin; Oviedo, Heidi C.; Herazo, Edwin; Campo-Arias, Adalberto

2016-01-01

Introduction. Quality of life could be quantified with the Menopause Rating Scale (MRS), which evaluates the severity of somatic, psychological, and urogenital symptoms in menopause. However, differential item functioning (DIF) analysis has not been applied previously. Objective. To establish the DIF of the psychological domain of the MRS in Colombian women. Methods. 4,009 women aged between 40 and 59 years, who participated in the CAVIMEC (Calidad de Vida en la Menopausia y Etnias Colombianas) project, were included. Average age was 49.0 ± 5.9 years. Women were classified in mestizo, Afro-Colombian, and indigenous. The results were presented as averages and standard deviation (X ± SD). A p value <0.001 was considered statistically significant. Results. In mestizo women, the highest X ± SD were obtained in physical and mental exhaustion (PME) (0.86 ± 0.93) and the lowest ones in anxiety (0.44 ± 0.79). In Afro-Colombian women, an average score of 0.99 ± 1.07 for PME and 0.63 ± 0.88 for anxiety was gotten. Indigenous women obtained an increased average score for PME (1.33 ± 0.93). The lowest score was evidenced in depressive mood (0.50 ± 0.81), which is different from other Colombian women (p < 0.001). Conclusions. The psychological items of the MRS show differential functioning according to the ethnic group, which may induce systematic error in the measurement of the construct. PMID:27847825

Differential Item Functioning of the Psychological Domain of the Menopause Rating Scale.

Science.gov (United States)

Monterrosa-Castro, Alvaro; Portela-Buelvas, Katherin; Oviedo, Heidi C; Herazo, Edwin; Campo-Arias, Adalberto

2016-01-01

Introduction. Quality of life could be quantified with the Menopause Rating Scale (MRS), which evaluates the severity of somatic, psychological, and urogenital symptoms in menopause. However, differential item functioning (DIF) analysis has not been applied previously. Objective . To establish the DIF of the psychological domain of the MRS in Colombian women. Methods . 4,009 women aged between 40 and 59 years, who participated in the CAVIMEC (Calidad de Vida en la Menopausia y Etnias Colombianas) project, were included. Average age was 49.0 ± 5.9 years. Women were classified in mestizo, Afro-Colombian, and indigenous. The results were presented as averages and standard deviation ( X ± SD). A p value <0.001 was considered statistically significant. Results . In mestizo women, the highest X ± SD were obtained in physical and mental exhaustion (PME) (0.86 ± 0.93) and the lowest ones in anxiety (0.44 ± 0.79). In Afro-Colombian women, an average score of 0.99 ± 1.07 for PME and 0.63 ± 0.88 for anxiety was gotten. Indigenous women obtained an increased average score for PME (1.33 ± 0.93). The lowest score was evidenced in depressive mood (0.50 ± 0.81), which is different from other Colombian women ( p < 0.001). Conclusions . The psychological items of the MRS show differential functioning according to the ethnic group, which may induce systematic error in the measurement of the construct.

A simulation study provided sample size guidance for differential item functioning (DIF) studies using short scales

DEFF Research Database (Denmark)

Scott, Neil W.; Fayers, Peter M.; Bottomley, Andrew

2009-01-01

Differential item functioning (DIF) analyses are increasingly used to evaluate health-related quality of life (HRQoL) instruments, which often include relatively short subscales. Computer simulations were used to explore how various factors including scale length affect analysis of DIF by ordinal...... logistic regression....

Differential Item Functioning (DIF) Etnis pada Big Five Inventory (BFI) versi Adaptasi Fakultas Psikologi Universitas Sumatera Utara

OpenAIRE

Manik, Hitler

2014-01-01

Big Five Inventory (BFI) is one of personality test had been adapted into Indonesia language. More research had been developed to adapt the Indonesian Big Five Inventory. The purpose of this research is to check whether BFI’s personality test is fair if apply to ethnic of Batak Toba and Java. Therefore, examination of BFI’s items is needed. In psychology, especially in psychometric study, it is called Differential Item Functioning (DIF). Subject in this research is 327 people around 18 to 40 ...

Item Response Theory Analysis of the Psychopathic Personality Inventory-Revised.

Science.gov (United States)

Eichenbaum, Alexander E; Marcus, David K; French, Brian F

2017-06-01

This study examined item and scale functioning in the Psychopathic Personality Inventory-Revised (PPI-R) using an item response theory analysis. PPI-R protocols from 1,052 college student participants (348 male, 704 female) were analyzed. Analyses were conducted on the 131 self-report items comprising the PPI-R's eight content scales, using a graded response model. Scales collected a majority of their information about respondents possessing higher than average levels of the traits being measured. Each scale contained at least some items that evidenced limited ability to differentiate between respondents with differing levels of the trait being measured. Moreover, 80 items (61.1%) yielded significantly different responses between men and women presumably possessing similar levels of the trait being measured. Item performance was also influenced by the scoring format (directly scored vs. reverse-scored) of the items. Overall, the results suggest that the PPI-R, despite identifying psychopathic personality traits in individuals possessing high levels of those traits, may not identify these traits equally well for men and women, and scores are likely influenced by the scoring format of the individual item and scale.

Differential Item Functioning (DIF) among Spanish-Speaking English Language Learners (ELLs) in State Science Tests

Science.gov (United States)

Ilich, Maria O.

Psychometricians and test developers evaluate standardized tests for potential bias against groups of test-takers by using differential item functioning (DIF). English language learners (ELLs) are a diverse group of students whose native language is not English. While they are still learning the English language, they must take their standardized tests for their school subjects, including science, in English. In this study, linguistic complexity was examined as a possible source of DIF that may result in test scores that confound science knowledge with a lack of English proficiency among ELLs. Two years of fifth-grade state science tests were analyzed for evidence of DIF using two DIF methods, Simultaneous Item Bias Test (SIBTest) and logistic regression. The tests presented a unique challenge in that the test items were grouped together into testlets---groups of items referring to a scientific scenario to measure knowledge of different science content or skills. Very large samples of 10, 256 students in 2006 and 13,571 students in 2007 were examined. Half of each sample was composed of Spanish-speaking ELLs; the balance was comprised of native English speakers. The two DIF methods were in agreement about the items that favored non-ELLs and the items that favored ELLs. Logistic regression effect sizes were all negligible, while SIBTest flagged items with low to high DIF. A decrease in socioeconomic status and Spanish-speaking ELL diversity may have led to inconsistent SIBTest effect sizes for items used in both testing years. The DIF results for the testlets suggested that ELLs lacked sufficient opportunity to learn science content. The DIF results further suggest that those constructed response test items requiring the student to draw a conclusion about a scientific investigation or to plan a new investigation tended to favor ELLs.

Identifying potential misfit items in cognitive process of learning engineering mathematics based on Rasch model

International Nuclear Information System (INIS)

Ataei, Sh; Mahmud, Z; Khalid, M N

2014-01-01

The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.

Gender-based Differential Item Functioning in the Application of the Theory of Planned Behavior for the Study of Entrepreneurial Intentions.

Science.gov (United States)

Zampetakis, Leonidas A; Bakatsaki, Maria; Litos, Charalambos; Kafetsios, Konstantinos G; Moustakis, Vassilis

2017-01-01

Over the past years the percentage of female entrepreneurs has increased, yet it is still far below of that for males. Although various attempts have been made to explain differences in mens' and women's entrepreneurial attitudes and intentions, the extent to which those differences are due to self-report biases has not been yet considered. The present study utilized Differential Item Functioning (DIF) to compare men and women's reporting on entrepreneurial intentions. DIF occurs in situations where members of different groups show differing probabilities of endorsing an item despite possessing the same level of the ability that the item is intended to measure. Drawing on the theory of planned behavior (TPB), the present study investigated whether constructs such as entrepreneurial attitudes, perceived behavioral control, subjective norms and intention would show gender differences and whether these gender differences could be explained by DIF. Using DIF methods on a dataset of 1800 Greek participants (50.4% female) indicated that differences at the item-level are almost non-existent. Moreover, the differential test functioning (DTF) analysis, which allows assessing the overall impact of DIF effects with all items being taken into account simultaneously, suggested that the effect of DIF across all the items for each scale was negligible. Future research should consider that measurement invariance can be assumed when using TPB constructs for the study of entrepreneurial motivation independent of gender.

A Differential Item Functional Analysis by Age of Perceived Interpersonal Discrimination in a Multi-racial/ethnic Sample of Adults.

Science.gov (United States)

Owens, Sherry; Kristjansson, Alfgeir L; Hunte, Haslyn E R

2015-11-05

We investigated whether individual items on the nine item William's Perceived Everyday Discrimination Scale (EDS) functioned differently by age (ethnic group. Overall, Asian and Hispanic respondents reported less discrimination than Whites; on the other hand, African Americans and Black Caribbeans reported more discrimination than Whites. Regardless of race/ethnicity, the younger respondents (aged ethnicity, the results were mixed for 19 out of 45 tests of DIF (40%). No differences in item function were observed among Black Caribbeans. "Being called names or insulted" and others acting as "if they are afraid" of the respondents were the only two items that did not exhibit differential item functioning by age across all racial/ethnic groups. Overall, our findings suggest that the EDS scale should be used with caution in multi-age multi-racial/ethnic samples.

Differential item functional analysis on pedagogic and content knowledge (PCK) questionnaire for Indonesian teachers using RASCH model

Science.gov (United States)

Rahmani, B. D.

2018-01-01

The purpose of this paper is to evaluate Indonesian senior high school teacher’s pedagogical content knowledge also their perception toward curriculum changing in West Java Indonesia. The data used in this study were derived from a questionnaire survey conducted among teachers in Bandung, West Java. A total of 61 usable responses were collected. The Differential Item Functioning (DIFF) was used to analyze the data whether the item had a difference or not toward gender, education background also on school location. However, the result showed that there was no any significant difference on gender and school location toward the item response but educational background. As a conclusion, the teacher’s educational background influence on giving the response to the questionnaire. Therefore, it is suggested in the future to construct the items on the questionnaire which is coped the differences of the participant particularly the educational background.

Gender-based Differential Item Functioning in the Application of the Theory of Planned Behavior for the Study of Entrepreneurial Intentions

Science.gov (United States)

Zampetakis, Leonidas A.; Bakatsaki, Maria; Litos, Charalambos; Kafetsios, Konstantinos G.; Moustakis, Vassilis

2017-01-01

Over the past years the percentage of female entrepreneurs has increased, yet it is still far below of that for males. Although various attempts have been made to explain differences in mens’ and women’s entrepreneurial attitudes and intentions, the extent to which those differences are due to self-report biases has not been yet considered. The present study utilized Differential Item Functioning (DIF) to compare men and women’s reporting on entrepreneurial intentions. DIF occurs in situations where members of different groups show differing probabilities of endorsing an item despite possessing the same level of the ability that the item is intended to measure. Drawing on the theory of planned behavior (TPB), the present study investigated whether constructs such as entrepreneurial attitudes, perceived behavioral control, subjective norms and intention would show gender differences and whether these gender differences could be explained by DIF. Using DIF methods on a dataset of 1800 Greek participants (50.4% female) indicated that differences at the item-level are almost non-existent. Moreover, the differential test functioning (DTF) analysis, which allows assessing the overall impact of DIF effects with all items being taken into account simultaneously, suggested that the effect of DIF across all the items for each scale was negligible. Future research should consider that measurement invariance can be assumed when using TPB constructs for the study of entrepreneurial motivation independent of gender. PMID:28386244

Differential item functioning of pathological gambling criteria: an examination of gender, race/ethnicity, and age.

Science.gov (United States)

Sacco, Paul; Torres, Luis R; Cunningham-Williams, Renee M; Woods, Carol; Unick, G Jay

2011-06-01

This study tested for the presence of differential item functioning (DIF) in DSM-IV Pathological Gambling Disorder (PGD) criteria based on gender, race/ethnicity and age. Using a nationally representative sample of adults from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), indicating current gambling (n = 10,899), Multiple Indicator-Multiple Cause (MIMIC) models tested for DIF, controlling for income, education, and marital status. Compared to the reference groups (i.e., Male, Caucasian, and ages 25-59 years), women (OR = 0.62; P gambling to escape (Criterion 5) (OR = 2.22; P < .001) but young adults (OR = 0.62; P < .05) were less likely to endorse it. African Americans (OR = 2.50; P < .001) and Hispanics were more likely to endorse trying to cut back (Criterion 3) (OR = 2.01; P < .01). African Americans were more likely to endorse the suffering losses (OR = 2.27; P < .01) criterion. Young adults were more likely to endorse chasing losses (Criterion 9) (OR = 1.81; P < .01) while older adults were less likely to endorse this criterion (OR = 0.76; P < .05). Further research is needed to identify factors contributing to DIF, address criteria level bias, and examine differential test functioning.

Differential Item Functioning of Pathological Gambling Criteria: An Examination of Gender, Race/Ethnicity, and Age

OpenAIRE

Sacco, Paul; Torres, Luis R.; Cunningham-Williams, Renee M.; Woods, Carol; Unick, G. Jay

2011-01-01

This study tested for the presence of differential item functioning (DIF) in DSM-IV Pathological Gambling Disorder (PGD) criteria based on gender, race/ethnicity and age. Using a nationally representative sample of adults from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), indicating current gambling (n = 10,899), Multiple Indicator-Multiple Cause (MIMIC) models tested for DIF, controlling for income, education, and marital status. Compared to the reference grou...

A leukocyte activation test identifies food items which induce release of DNA by innate immune peripheral blood leucocytes.

Science.gov (United States)

Garcia-Martinez, Irma; Weiss, Theresa R; Yousaf, Muhammad N; Ali, Ather; Mehal, Wajahat Z

2018-01-01

Leukocyte activation (LA) testing identifies food items that induce a patient specific cellular response in the immune system, and has recently been shown in a randomized double blinded prospective study to reduce symptoms in patients with irritable bowel syndrome (IBS). We hypothesized that test reactivity to particular food items, and the systemic immune response initiated by these food items, is due to the release of cellular DNA from blood immune cells. We tested this by quantifying total DNA concentration in the cellular supernatant of immune cells exposed to positive and negative foods from 20 healthy volunteers. To establish if the DNA release by positive samples is a specific phenomenon, we quantified myeloperoxidase (MPO) in cellular supernatants. We further assessed if a particular immune cell population (neutrophils, eosinophils, and basophils) was activated by the positive food items by flow cytometry analysis. To identify the signaling pathways that are required for DNA release we tested if specific inhibitors of key signaling pathways could block DNA release. Foods with a positive LA test result gave a higher supernatant DNA content when compared to foods with a negative result. This was specific as MPO levels were not increased by foods with a positive LA test. Protein kinase C (PKC) inhibitors resulted in inhibition of positive food stimulated DNA release. Positive foods resulted in CD63 levels greater than negative foods in eosinophils in 76.5% of tests. LA test identifies food items that result in release of DNA and activation of peripheral blood innate immune cells in a PKC dependent manner, suggesting that this LA test identifies food items that result in release of inflammatory markers and activation of innate immune cells. This may be the basis for the improvement in symptoms in IBS patients who followed an LA test guided diet.

Evaluation of the Fecal Incontinence Quality of Life Scale (FIQL) using item response theory reveals limitations and suggests revisions.

Science.gov (United States)

Peterson, Alexander C; Sutherland, Jason M; Liu, Guiping; Crump, R Trafford; Karimuddin, Ahmer A

2018-06-01

The Fecal Incontinence Quality of Life Scale (FIQL) is a commonly used patient-reported outcome measure for fecal incontinence, often used in clinical trials, yet has not been validated in English since its initial development. This study uses modern methods to thoroughly evaluate the psychometric characteristics of the FIQL and its potential for differential functioning by gender. This study analyzed prospectively collected patient-reported outcome data from a sample of patients prior to colorectal surgery. Patients were recruited from 14 general and colorectal surgeons in Vancouver Coastal Health hospitals in Vancouver, Canada. Confirmatory factor analysis was used to assess construct validity. Item response theory was used to evaluate test reliability, describe item-level characteristics, identify local item dependence, and test for differential functioning by gender. 236 patients were included for analysis, with mean age 58 and approximately half female. Factor analysis failed to identify the lifestyle, coping, depression, and embarrassment domains, suggesting lack of construct validity. Items demonstrated low difficulty, indicating that the test has the highest reliability among individuals who have low quality of life. Five items are suggested for removal or replacement. Differential test functioning was minimal. This study has identified specific improvements that can be made to each domain of the Fecal Incontinence Quality of Life Scale and to the instrument overall. Formatting, scoring, and instructions may be simplified, and items with higher difficulty developed. The lifestyle domain can be used as is. The embarrassment domain should be significantly revised before use.

Identifying the most efficient items from the Mini-Mental State Examination for cognitive function assessment in older Taiwanese patients.

Science.gov (United States)

Lou, Meei-Fang; Dai, Yu-Tzu; Huang, Guey-Shiun; Yu, Po-Jui

2007-03-01

The purpose of the study was to identify the most efficient items from the Mini-Mental State Examination for assessment of cognitive function. The Mini-Mental State Examination is the most frequently used cognitive screening instrument. However, the Mini-Mental State Examination has been criticized for insensitivity to mild cognitive dysfunction, limited memory assessment and variability in level of difficulty of the individual items. This study used secondary data analysis. Item response theory two-parameter model was used to analyse the data from the admission assessment of mental status by the Mini-Mental State Examination for 801 patients. By using item response analysis, 16 items were selected from the original 30-item Mini-Mental State Examination. The 16 items included mainly the measures of orientation, recall and attention and calculation. The internal consistency of the 16-item Mini-Mental State Examination was 0.84. The proposed new cut-off point for the 16-item Mini-Mental State Examination was 11. The correct classification rate was 0.94, the sensitivity was 100% and the specificity was 97.4%, when compared with the original 30-item Mini-Mental State Examination from the cut-off point of 24. This new cut-off point was determined for the purpose of over-identifying patients at risk so as to ensure early detection of and prevention from the onset of cognitive disturbance. Only a few items are needed to describe the subject's cognitive status. Using item response theory analysis, the study found that the Mini-Mental State Examination could be simplified. Deleting the items with less variation makes this assessment tool not only shorter, easier to administer and less strenuous for respondents, but also enables one to maintain validity as a cognitive function test for clinical setting.

A comparison of three methods of assessing differential item functioning (DIF) in the Hospital Anxiety Depression Scale: ordinal logistic regression, Rasch analysis and the Mantel chi-square procedure.

Science.gov (United States)

Cameron, Isobel M; Scott, Neil W; Adler, Mats; Reid, Ian C

2014-12-01

It is important for clinical practice and research that measurement scales of well-being and quality of life exhibit only minimal differential item functioning (DIF). DIF occurs where different groups of people endorse items in a scale to different extents after being matched by the intended scale attribute. We investigate the equivalence or otherwise of common methods of assessing DIF. Three methods of measuring age- and sex-related DIF (ordinal logistic regression, Rasch analysis and Mantel χ(2) procedure) were applied to Hospital Anxiety Depression Scale (HADS) data pertaining to a sample of 1,068 patients consulting primary care practitioners. Three items were flagged by all three approaches as having either age- or sex-related DIF with a consistent direction of effect; a further three items identified did not meet stricter criteria for important DIF using at least one method. When applying strict criteria for significant DIF, ordinal logistic regression was slightly less sensitive. Ordinal logistic regression, Rasch analysis and contingency table methods yielded consistent results when identifying DIF in the HADS depression and HADS anxiety scales. Regardless of methods applied, investigators should use a combination of statistical significance, magnitude of the DIF effect and investigator judgement when interpreting the results.

Funcionamento diferencial de itens para avaliar a agressividade de universitários Differential items functioning to assess aggressiveness in college students

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Fermino Fernandes Sisto

2008-01-01

Full Text Available Nesta pesquisa buscou-se evidência de validade de construto relacionada ao funcionamento dos itens para diferenciar sexos em um instrumento de agressividade. Participaram 445 universitários, de ambos os sexos, dos cursos de Engenharia, Computação e Psicologia. A escala de agressividade composta por 81 itens foi aplicada coletivamente, em sala de aula, nos estudantes que consentiram em participar do estudo. Os itens do instrumento foram analisados por meio do modelo Rasch. Vinte e oito itens apresentaram funcionamento diferencial, sendo 15 condutas mais características de pessoas do sexo feminino e outras 13 mais características do masculino. Os índices de precisão foram de 0,99 para os itens e 0,86 para as pessoas. Conclui-se que a agressividade pode ser medida separadamente em razão do sexo.In this research evidences of construct validity were searched analyzing the differential functioning items related to aggressiveness. The participants were 445 college students of both genders, attending the courses of Engineering, Computing and Psychology. The scale of aggressiveness composed by 81 items was collectively applied, in the classroom, to the students who consented to participate in the study. The items of the instrument were studied by means of the Rasch model. Twenty-eight items presented differential functioning item, 15 were characterized as typical for females and 13 for males. The reliability coefficients were 0.99 to the items and 0.86 to the persons. It was concluded that the aggressiveness can be measured separately on the basis of gender.

Comparing Two Versions of the MEOCS Using Differential Item Functioning

National Research Council Canada - National Science Library

Truhon, Stephen

2003-01-01

...) from item response theory (IRT). DIF was found for the majority of the 40 items examined, although in many cases the DIF indicated improvements in the revised items. Implications for these scales and for the use of IRT with the MEOCS are discussed.

Checking Equity: Why Differential Item Functioning Analysis Should Be a Routine Part of Developing Conceptual Assessments

Czech Academy of Sciences Publication Activity Database

Martinková, Patrícia; Drabinová, Adéla; Liaw, Y.L.; Sanders, E.A.; McFarland, J.L.; Price, R.M.

2017-01-01

Roč. 16, č. 2 (2017), č. článku rm2. ISSN 1931-7913 R&D Projects: GA ČR GJ15-15856Y Grant - others:NSF(US) DUE-1043443 Institutional support: RVO:67985807 Keywords : differential item functioning * fairness * conceptual assessments * concept inventory * undergraduate education * bias Subject RIV: AM - Education OBOR OECD: Education , special (to gifted persons, those with learning disabilities) Impact factor: 3.930, year: 2016

Improving measurement of injection drug risk behavior using item response theory.

Science.gov (United States)

Janulis, Patrick

2014-03-01

Recent research highlights the multiple steps to preparing and injecting drugs and the resultant viral threats faced by drug users. This research suggests that more sensitive measurement of injection drug HIV risk behavior is required. In addition, growing evidence suggests there are gender differences in injection risk behavior. However, the potential for differential item functioning between genders has not been explored. To explore item response theory as an improved measurement modeling technique that provides empirically justified scaling of injection risk behavior and to examine for potential gender-based differential item functioning. Data is used from three studies in the National Institute on Drug Abuse's Criminal Justice Drug Abuse Treatment Studies. A two-parameter item response theory model was used to scale injection risk behavior and logistic regression was used to examine for differential item functioning. Item fit statistics suggest that item response theory can be used to scale injection risk behavior and these models can provide more sensitive estimates of risk behavior. Additionally, gender-based differential item functioning is present in the current data. Improved measurement of injection risk behavior using item response theory should be encouraged as these models provide increased congruence between construct measurement and the complexity of injection-related HIV risk. Suggestions are made to further improve injection risk behavior measurement. Furthermore, results suggest direct comparisons of composite scores between males and females may be misleading and future work should account for differential item functioning before comparing levels of injection risk behavior.

deltaPlotR: An R Package for Di?erential Item Functioning Analysis with Ango? s Delta Plot

OpenAIRE

David Magis; Bruno Facon

2014-01-01

Angoff's delta plot is a straightforward and not computationally intensive method to identify differential item functioning (DIF) among dichotomously scored items. This approach was recently improved by proposing an optimal threshold selection and by considering several item purification processes. Moreover, to support practical DIF analyses with the delta plot and these improvements, the R package deltaPlotR was also developed. The purpose of this paper is twofold: to outline the delta plot ...

Assessment of Differential Item Functioning in Health-Related Outcomes: A Simulation and Empirical Analysis with Hierarchical Polytomous Data

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Zahra Sharafi

2017-01-01

Full Text Available Background. The purpose of this study was to evaluate the effectiveness of two methods of detecting differential item functioning (DIF in the presence of multilevel data and polytomously scored items. The assessment of DIF with multilevel data (e.g., patients nested within hospitals, hospitals nested within districts from large-scale assessment programs has received considerable attention but very few studies evaluated the effect of hierarchical structure of data on DIF detection for polytomously scored items. Methods. The ordinal logistic regression (OLR and hierarchical ordinal logistic regression (HOLR were utilized to assess DIF in simulated and real multilevel polytomous data. Six factors (DIF magnitude, grouping variable, intraclass correlation coefficient, number of clusters, number of participants per cluster, and item discrimination parameter with a fully crossed design were considered in the simulation study. Furthermore, data of Pediatric Quality of Life Inventory™ (PedsQL™ 4.0 collected from 576 healthy school children were analyzed. Results. Overall, results indicate that both methods performed equivalently in terms of controlling Type I error and detection power rates. Conclusions. The current study showed negligible difference between OLR and HOLR in detecting DIF with polytomously scored items in a hierarchical structure. Implications and considerations while analyzing real data were also discussed.

A Novel Method to Identify Differential Pathways in Hippocampus Alzheimer's Disease.

Science.gov (United States)

Liu, Chun-Han; Liu, Lian

2017-05-08

BACKGROUND Alzheimer's disease (AD) is the most common type of dementia. The objective of this paper is to propose a novel method to identify differential pathways in hippocampus AD. MATERIAL AND METHODS We proposed a combined method by merging existed methods. Firstly, pathways were identified by four known methods (DAVID, the neaGUI package, the pathway-based co-expressed method, and the pathway network approach), and differential pathways were evaluated through setting weight thresholds. Subsequently, we combined all pathways by a rank-based algorithm and called the method the combined method. Finally, common differential pathways across two or more of five methods were selected. RESULTS Pathways obtained from different methods were also different. The combined method obtained 1639 pathways and 596 differential pathways, which included all pathways gained from the four existing methods; hence, the novel method solved the problem of inconsistent results. Besides, a total of 13 common pathways were identified, such as metabolism, immune system, and cell cycle. CONCLUSIONS We have proposed a novel method by combining four existing methods based on a rank product algorithm, and identified 13 significant differential pathways based on it. These differential pathways might provide insight into treatment and diagnosis of hippocampus AD.

Differential item functioning (DIF) in the EORTC QLQ-C30: a comparison of baseline, on-treatment and off-treatment data

DEFF Research Database (Denmark)

Scott, Neil W.; Fayers, Peter M.; Aaronson, Neil K.

2009-01-01

Differential item functioning (DIF) analyses can be used to explore translation, cultural, gender or other differences in the performance of quality of life (QoL) instruments. These analyses are commonly performed using "baseline" or pretreatment data. We previously reported DIF analyses to examine...

Expression Profiling of Differentiating Emerin-Null Myogenic Progenitor Identifies Molecular Pathways Implicated in Their Impaired Differentiation

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Ashvin Iyer

2017-10-01

Full Text Available Mutations in the gene encoding emerin cause Emery-Dreifuss muscular dystrophy (EDMD, a disorder causing progressive skeletal muscle wasting, irregular heart rhythms and contractures of major tendons. RNA sequencing was performed on differentiating wildtype and emerin-null myogenic progenitors to identify molecular pathways implicated in EDMD, 340 genes were uniquely differentially expressed during the transition from day 0 to day 1 in wildtype cells. 1605 genes were uniquely expressed in emerin-null cells; 1706 genes were shared among both wildtype and emerin-null cells. One thousand and forty-seven transcripts showed differential expression during the transition from day 1 to day 2. Four hundred and thirty-one transcripts showed altered expression in both wildtype and emerin-null cells. Two hundred and ninety-five transcripts were differentially expressed only in emerin-null cells and 321 transcripts were differentially expressed only in wildtype cells. DAVID, STRING and Ingenuity Pathway Analysis identified pathways implicated in impaired emerin-null differentiation, including cell signaling, cell cycle checkpoints, integrin signaling, YAP/TAZ signaling, stem cell differentiation, and multiple muscle development and myogenic differentiation pathways. Functional enrichment analysis showed biological functions associated with the growth of muscle tissue and myogenesis of skeletal muscle were inhibited. The large number of differentially expressed transcripts upon differentiation induction suggests emerin functions during transcriptional reprograming of progenitors to committed myoblasts.

Funcionamiento diferencial del item en la evaluación internacional PISA. Detección y comprensión. [Differential Item Functioning in the PISA Project: Detection and Understanding

Directory of Open Access Journals (Sweden)

Paula Elosua

2006-08-01

Full Text Available This report analyses the differential item functioning (DIF in the Programme for Indicators of Student Achievement PISA2000. The items studied are coming from the Reading Comprehension Test. We analyzed the released items from this year because we wanted to join the detection of DIF and its understanding. The reference group is the sample of United Kingdom and the focal group is the Spanish sample. The procedures of detection are Mantel-Haenszel, Logistic Regression and the standardized mean difference, and their extensions for polytomous items. Two items were flagged and the post-hoc analysis didn’t explain the causes of DIF entirely. Este trabajo analiza el funcionamiento diferencial del ítem (FDI de la prueba de comprensión lectora de la evaluación PISA2000 entre la muestras del Reino Unido y España. Se estudian los ítems liberados con el fin de aunar las fases de detección del FDI con la comprensión de sus causas. En la fase de detección se comparan los resultados de los procedimientos Mantel-Haenszel, Regresión Logística y Medias Estandarizadas en sus versiones para ítems dicotómicos y politómicos. Los resultados muestran que dos ítems presentan funcionamiento diferencial aunque el estudio post-hoc llevado a cabo sobre su contenido no ha podido precisar sus causas.

Item and test analysis to identify quality multiple choice questions (MCQS from an assessment of medical students of Ahmedabad, Gujarat

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Sanju Gajjar

2014-01-01

Full Text Available Background: Multiple choice questions (MCQs are frequently used to assess students in different educational streams for their objectivity and wide reach of coverage in less time. However, the MCQs to be used must be of quality which depends upon its difficulty index (DIF I, discrimination index (DI and distracter efficiency (DE. Objective: To evaluate MCQs or items and develop a pool of valid items by assessing with DIF I, DI and DE and also to revise/ store or discard items based on obtained results. Settings: Study was conducted in a medical school of Ahmedabad. Materials and Methods: An internal examination in Community Medicine was conducted after 40 hours teaching during 1 st MBBS which was attended by 148 out of 150 students. Total 50 MCQs or items and 150 distractors were analyzed. Statistical Analysis: Data was entered and analyzed in MS Excel 2007 and simple proportions, mean, standard deviations, coefficient of variation were calculated and unpaired t test was applied. Results: Out of 50 items, 24 had "good to excellent" DIF I (31 - 60% and 15 had "good to excellent" DI (> 0.25. Mean DE was 88.6% considered as ideal/ acceptable and non functional distractors (NFD were only 11.4%. Mean DI was 0.14. Poor DI (< 0.15 with negative DI in 10 items indicates poor preparedness of students and some issues with framing of at least some of the MCQs. Increased proportion of NFDs (incorrect alternatives selected by < 5% students in an item decrease DE and makes it easier. There were 15 items with 17 NFDs, while rest items did not have any NFD with mean DE of 100%. Conclusion: Study emphasizes the selection of quality MCQs which truly assess the knowledge and are able to differentiate the students of different abilities in correct manner.

Assessing the Straightforwardly-Worded Brief Fear of Negative Evaluation Scale for Differential Item Functioning Across Gender and Ethnicity.

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Harpole, Jared K; Levinson, Cheri A; Woods, Carol M; Rodebaugh, Thomas L; Weeks, Justin W; Brown, Patrick J; Heimberg, Richard G; Menatti, Andrew R; Blanco, Carlos; Schneier, Franklin; Liebowitz, Michael

2015-06-01

The Brief Fear of Negative Evaluation Scale (BFNE; Leary Personality and Social Psychology Bulletin , 9, 371-375, 1983) assesses fear and worry about receiving negative evaluation from others. Rodebaugh et al. Psychological Assessment, 16 , 169-181, (2004) found that the BFNE is composed of a reverse-worded factor (BFNE-R) and straightforwardly-worded factor (BFNE-S). Further, they found the BFNE-S to have better psychometric properties and provide more information than the BFNE-R. Currently there is a lack of research regarding the measurement invariance of the BFNE-S across gender and ethnicity with respect to item thresholds. The present study uses item response theory (IRT) to test the BFNE-S for differential item functioning (DIF) related to gender and ethnicity (White, Asian, and Black). Six data sets consisting of clinical, community, and undergraduate participants were utilized ( N =2,109). The factor structure of the BFNE-S was confirmed using categorical confirmatory factor analysis, IRT model assumptions were tested, and the BFNE-S was evaluated for DIF. Item nine demonstrated significant non-uniform DIF between White and Black participants. No other items showed significant uniform or non-uniform DIF across gender or ethnicity. Results suggest the BFNE-S can be used reliably with men and women and Asian and White participants. More research is needed to understand the implications of using the BFNE-S with Black participants.

Item bias detection in the Hospital Anxiety and Depression Scale using structural equation modeling: comparison with other item bias detection methods

NARCIS (Netherlands)

Verdam, M.G.E.; Oort, F.J.; Sprangers, M.A.G.

Purpose Comparison of patient-reported outcomes may be invalidated by the occurrence of item bias, also known as differential item functioning. We show two ways of using structural equation modeling (SEM) to detect item bias: (1) multigroup SEM, which enables the detection of both uniform and

Development of a subjective cognitive decline questionnaire using item response theory: a pilot study.

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Gifford, Katherine A; Liu, Dandan; Romano, Raymond; Jones, Richard N; Jefferson, Angela L

2015-12-01

Subjective cognitive decline (SCD) may indicate unhealthy cognitive changes, but no standardized SCD measurement exists. This pilot study aims to identify reliable SCD questions. 112 cognitively normal (NC, 76±8 years, 63% female), 43 mild cognitive impairment (MCI; 77±7 years, 51% female), and 33 diagnostically ambiguous participants (79±9 years, 58% female) were recruited from a research registry and completed 57 self-report SCD questions. Psychometric methods were used for item-reduction. Factor analytic models assessed unidimensionality of the latent trait (SCD); 19 items were removed with extreme response distribution or trait-fit. Item response theory (IRT) provided information about question utility; 17 items with low information were dropped. Post-hoc simulation using computerized adaptive test (CAT) modeling selected the most commonly used items (n=9 of 21 items) that represented the latent trait well (r=0.94) and differentiated NC from MCI participants (F(1,146)=8.9, p=0.003). Item response theory and computerized adaptive test modeling identified nine reliable SCD items. This pilot study is a first step toward refining SCD assessment in older adults. Replication of these findings and validation with Alzheimer's disease biomarkers will be an important next step for the creation of a SCD screener.

Identifying the Source of Misfit in Item Response Theory Models.

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Liu, Yang; Maydeu-Olivares, Alberto

2014-01-01

When an item response theory model fails to fit adequately, the items for which the model provides a good fit and those for which it does not must be determined. To this end, we compare the performance of several fit statistics for item pairs with known asymptotic distributions under maximum likelihood estimation of the item parameters: (a) a mean and variance adjustment to bivariate Pearson's X(2), (b) a bivariate subtable analog to Reiser's (1996) overall goodness-of-fit test, (c) a z statistic for the bivariate residual cross product, and (d) Maydeu-Olivares and Joe's (2006) M2 statistic applied to bivariate subtables. The unadjusted Pearson's X(2) with heuristically determined degrees of freedom is also included in the comparison. For binary and ordinal data, our simulation results suggest that the z statistic has the best Type I error and power behavior among all the statistics under investigation when the observed information matrix is used in its computation. However, if one has to use the cross-product information, the mean and variance adjusted X(2) is recommended. We illustrate the use of pairwise fit statistics in 2 real-data examples and discuss possible extensions of the current research in various directions.

Differential Item Functioning in While-Listening Performance Tests: The Case of the International English Language Testing System (IELTS) Listening Module

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Aryadoust, Vahid

2012-01-01

This article investigates a version of the International English Language Testing System (IELTS) listening test for evidence of differential item functioning (DIF) based on gender, nationality, age, and degree of previous exposure to the test. Overall, the listening construct was found to be underrepresented, which is probably an important cause…

Symptom endorsement in men versus women with a diagnosis of depression: A differential item functioning approach.

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Cavanagh, Anna; Wilson, Coralie J; Caputi, Peter; Kavanagh, David J

2016-09-01

There is some evidence that, in contrast to depressed women, depressed men tend to report alternative symptoms that are not listed as standard diagnostic criteria. This may possibly lead to an under- or misdiagnosis of depression in men. This study aims to clarify whether depressed men and women report different symptoms. This study used data from the 2007 Australian National Survey of Mental Health and Wellbeing that was collected using the World Health Organization's Composite International Diagnostic Interview. Participants with a diagnosis of a depressive disorder with 12-month symptoms (n = 663) were identified and included in this study. Differential item functioning (DIF) was used to test whether depressed men and women endorse different features associated with their condition. Gender-related DIF was present for three symptoms associated with depression. Depressed women were more likely to report 'appetite/weight disturbance', whereas depressed men were more likely to report 'alcohol misuse' and 'substance misuse'. While the results may reflect a greater risk of co-occurring alcohol and substance misuse in men, inclusion of these features in assessments may improve the detection of depression in men, especially if standard depressive symptoms are under-reported. © The Author(s) 2016.

Using automatic item generation to create multiple-choice test items.

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Gierl, Mark J; Lai, Hollis; Turner, Simon R

2012-08-01

Many tests of medical knowledge, from the undergraduate level to the level of certification and licensure, contain multiple-choice items. Although these are efficient in measuring examinees' knowledge and skills across diverse content areas, multiple-choice items are time-consuming and expensive to create. Changes in student assessment brought about by new forms of computer-based testing have created the demand for large numbers of multiple-choice items. Our current approaches to item development cannot meet this demand. We present a methodology for developing multiple-choice items based on automatic item generation (AIG) concepts and procedures. We describe a three-stage approach to AIG and we illustrate this approach by generating multiple-choice items for a medical licensure test in the content area of surgery. To generate multiple-choice items, our method requires a three-stage process. Firstly, a cognitive model is created by content specialists. Secondly, item models are developed using the content from the cognitive model. Thirdly, items are generated from the item models using computer software. Using this methodology, we generated 1248 multiple-choice items from one item model. Automatic item generation is a process that involves using models to generate items using computer technology. With our method, content specialists identify and structure the content for the test items, and computer technology systematically combines the content to generate new test items. By combining these outcomes, items can be generated automatically. © Blackwell Publishing Ltd 2012.

Development of the PROMIS positive emotional and sensory expectancies of smoking item banks.

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Tucker, Joan S; Shadel, William G; Edelen, Maria Orlando; Stucky, Brian D; Li, Zhen; Hansen, Mark; Cai, Li

2014-09-01

The positive emotional and sensory expectancies of cigarette smoking include improved cognitive abilities, positive affective states, and pleasurable sensorimotor sensations. This paper describes development of Positive Emotional and Sensory Expectancies of Smoking item banks that will serve to standardize the assessment of this construct among daily and nondaily cigarette smokers. Data came from daily (N = 4,201) and nondaily (N =1,183) smokers who completed an online survey. To identify a unidimensional set of items, we conducted item factor analyses, item response theory analyses, and differential item functioning analyses. Additionally, we evaluated the performance of fixed-item short forms (SFs) and computer adaptive tests (CATs) to efficiently assess the construct. Eighteen items were included in the item banks (15 common across daily and nondaily smokers, 1 unique to daily, 2 unique to nondaily). The item banks are strongly unidimensional, highly reliable (reliability = 0.95 for both), and perform similarly across gender, age, and race/ethnicity groups. A SF common to daily and nondaily smokers consists of 6 items (reliability = 0.86). Results from simulated CATs indicated that, on average, less than 8 items are needed to assess the construct with adequate precision using the item banks. These analyses identified a new set of items that can assess the positive emotional and sensory expectancies of smoking in a reliable and standardized manner. Considerable efficiency in assessing this construct can be achieved by using the item bank SF, employing computer adaptive tests, or selecting subsets of items tailored to specific research or clinical purposes. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A 67-Item Stress Resilience item bank showing high content validity was developed in a psychosomatic sample.

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Obbarius, Nina; Fischer, Felix; Obbarius, Alexander; Nolte, Sandra; Liegl, Gregor; Rose, Matthias

2018-04-10

To develop the first item bank to measure Stress Resilience (SR) in clinical populations. Qualitative item development resulted in an initial pool of 131 items covering a broad theoretical SR concept. These items were tested in n=521 patients at a psychosomatic outpatient clinic. Exploratory and Confirmatory Factor Analysis (CFA), as well as other state-of-the-art item analyses and IRT were used for item evaluation and calibration of the final item bank. Out of the initial item pool of 131 items, we excluded 64 items (54 factor loading .3, 2 non-discriminative Item Response Curves, 4 Differential Item Functioning). The final set of 67 items indicated sufficient model fit in CFA and IRT analyses. Additionally, a 10-item short form with high measurement precision (SE≤.32 in a theta range between -1.8 and +1.5) was derived. Both the SR item bank and the SR short form were highly correlated with an existing static legacy tool (Connor-Davidson Resilience Scale). The final SR item bank and 10-item short form showed good psychometric properties. When further validated, they will be ready to be used within a framework of Computer-Adaptive Tests for a comprehensive assessment of the Stress-Construct. Copyright © 2018. Published by Elsevier Inc.

An emotional functioning item bank of 24 items for computerized adaptive testing (CAT) was established

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Petersen, Morten Aa.; Gamper, Eva-Maria; Costantini, Anna

2016-01-01

of the widely used EORTC Quality of Life questionnaire (QLQ-C30). STUDY DESIGN AND SETTING: On the basis of literature search and evaluations by international samples of experts and cancer patients, 38 candidate items were developed. The psychometric properties of the items were evaluated in a large...... international sample of cancer patients. This included evaluations of dimensionality, item response theory (IRT) model fit, differential item functioning (DIF), and of measurement precision/statistical power. RESULTS: Responses were obtained from 1,023 cancer patients from four countries. The evaluations showed...... that 24 items could be included in a unidimensional IRT model. DIF did not seem to have any significant impact on the estimation of EF. Evaluations indicated that the CAT measure may reduce sample size requirements by up to 50% compared to the QLQ-C30 EF scale without reducing power. CONCLUSION...

A symptom profile of depression among Asian Americans: is there evidence for differential item functioning of depressive symptoms?

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Kalibatseva, Z; Leong, F T L; Ham, E H

2014-09-01

Theoretical and clinical publications suggest the existence of cultural differences in the expression and experience of depression. Measurement non-equivalence remains a potential methodological explanation for the lower prevalence of depression among Asian Americans compared to European Americans. This study compared DSM-IV depressive symptoms among Asian Americans and European Americans using secondary data analysis of the Collaborative Psychiatric Epidemiology Surveys (CPES). The Composite International Diagnostic Interview (CIDI) was used for the assessment of depressive symptoms. Of the entire sample, 310 Asian Americans and 1974 European Americans reported depressive symptoms and were included in the analyses. Measurement variance was examined with an item response theory differential item functioning (IRT DIF) analysis. χ2 analyses indicated that, compared to Asian Americans, European American participants more frequently endorsed affective symptoms such as 'feeling depressed', 'feeling discouraged' and 'cried more often'. The IRT analysis detected DIF for four out of the 15 depression symptom items. At equal levels of depression, Asian Americans endorsed feeling worthless and appetite changes more easily than European Americans, and European Americans endorsed feeling nervous and crying more often than Asian Americans. Asian Americans did not seem to over-report somatic symptoms; however, European Americans seemed to report more affective symptoms than Asian Americans. The results suggest that there was measurement variance in a few of the depression items.

A review of the effects on IRT item parameter estimates with a focus on misbehaving common items in test equating

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Michalis P Michaelides

2010-10-01

Full Text Available Many studies have investigated the topic of change or drift in item parameter estimates in the context of Item Response Theory. Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.

A Review of the Effects on IRT Item Parameter Estimates with a Focus on Misbehaving Common Items in Test Equating.

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Michaelides, Michalis P

2010-01-01

Many studies have investigated the topic of change or drift in item parameter estimates in the context of item response theory (IRT). Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.

Extraction of items identifying hiesho (cold disorder) and their utility in young males and females.

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Sakaguchi, Shunji; Kuge, Hiroshi; Mori, Hidetoshi; Miyazaki, Junji; Tanaka, Tim Hideaki; Hanyu, Kazuyo; Takeda, Taro; Sasaki, Kazuro

2016-01-01

Hie (cold sensation) is one of the most common health complaints in Japan. Those who suffer from severe hie are considered as having hiesho (cold disorder). However, exact hiesho symptoms have not been defined clearly and the decision as to whether a person suffers from hiesho is subjective and based on self-awareness. The study was conducted in attempt to develop a standardized hiesho diagnostic scale. Subjects comprised 1 146 students. From the self-awareness of hiesho symptoms, males and females were divided into hiesho and non-hiesho groups. Physical, behavioral and adaptive characteristics were compared using the 24-item questionnaire (four-grade survey) and indicators for hiesho symptoms were extracted. Based on the scores, a receiver operating characteristic curve was drawn for the total ordinal scale score of the extracted items in relation to the presence and absence of hiesho symptoms, and an optimal cutoff value was determined. The self-awareness of having hiesho was found in 23.2% males and in 55.6% females. The sensitivity was 84.5% for males and 83.3% for females in the hiesho groups, and the specificity was 86.0% for males and 85.2% for females in the non-hiesho groups. A questionnaire consisting of the extracted items may be useful to identify hiesho in young males and females with a high level of accuracy.

A Psychometric Evaluation of the DSM-IV Criteria for Antisocial Personality Disorder: Dimensionality, Local Reliability, and Differential Item Functioning Across Gender.

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Paap, Muirne C S; Braeken, Johan; Pedersen, Geir; Urnes, Øyvind; Karterud, Sigmund; Wilberg, Theresa; Hummelen, Benjamin

2017-12-01

This study aims at evaluating the psychometric properties of the antisocial personality disorder (ASPD) criteria in a large sample of patients, most of whom had one or more personality disorders (PD). PD diagnoses were assessed by experienced clinicians using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition, Axis II PDs. Analyses were performed within an item response theory framework. Results of the analyses indicated that ASPD is a unidimensional construct that can be measured reliably at the upper range of the latent trait scale. Differential item functioning across gender was restricted to two criteria and had little impact on the latent ASPD trait level. Patients fulfilling both the adult ASPD criteria and the conduct disorder criteria had similar latent trait distributions as patients fulfilling only the adult ASPD criteria. Overall, the ASPD items fit the purpose of a diagnostic instrument well, that is, distinguishing patients with moderate from those with high antisocial personality scores.

Validation of MIMGO: a method to identify differentially expressed GO terms in a microarray dataset

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Yamada Yoichi

2012-12-01

Full Text Available Abstract Background We previously proposed an algorithm for the identification of GO terms that commonly annotate genes whose expression is upregulated or downregulated in some microarray data compared with in other microarray data. We call these “differentially expressed GO terms” and have named the algorithm “matrix-assisted identification method of differentially expressed GO terms” (MIMGO. MIMGO can also identify microarray data in which genes annotated with a differentially expressed GO term are upregulated or downregulated. However, MIMGO has not yet been validated on a real microarray dataset using all available GO terms. Findings We combined Gene Set Enrichment Analysis (GSEA with MIMGO to identify differentially expressed GO terms in a yeast cell cycle microarray dataset. GSEA followed by MIMGO (GSEA + MIMGO correctly identified (p Conclusions MIMGO is a reliable method to identify differentially expressed GO terms comprehensively.

Dissociating the neural correlates of intra-item and inter-item working-memory binding.

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Carinne Piekema

Full Text Available BACKGROUND: Integration of information streams into a unitary representation is an important task of our cognitive system. Within working memory, the medial temporal lobe (MTL has been conceptually linked to the maintenance of bound representations. In a previous fMRI study, we have shown that the MTL is indeed more active during working-memory maintenance of spatial associations as compared to non-spatial associations or single items. There are two explanations for this result, the mere presence of the spatial component activates the MTL, or the MTL is recruited to bind associations between neurally non-overlapping representations. METHODOLOGY/PRINCIPAL FINDINGS: The current fMRI study investigates this issue further by directly comparing intrinsic intra-item binding (object/colour, extrinsic intra-item binding (object/location, and inter-item binding (object/object. The three binding conditions resulted in differential activation of brain regions. Specifically, we show that the MTL is important for establishing extrinsic intra-item associations and inter-item associations, in line with the notion that binding of information processed in different brain regions depends on the MTL. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that different forms of working-memory binding rely on specific neural structures. In addition, these results extend previous reports indicating that the MTL is implicated in working-memory maintenance, challenging the classic distinction between short-term and long-term memory systems.

Differential proteomic and tissue expression analyses identify valuable diagnostic biomarkers of hepatocellular differentiation and hepatoid adenocarcinomas.

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Reis, Henning; Padden, Juliet; Ahrens, Maike; Pütter, Carolin; Bertram, Stefanie; Pott, Leona L; Reis, Anna-Carinna; Weber, Frank; Juntermanns, Benjamin; Hoffmann, Andreas-C; Eisenacher, Martin; Schlaak, Joörg F; Canbay, Ali; Meyer, Helmut E; Sitek, Barbara; Baba, Hideo A

2015-10-01

The exact discrimination of lesions with true hepatocellular differentiation from secondary tumours and neoplasms with hepatocellular histomorphology like hepatoid adenocarcinomas (HAC) is crucial. Therefore, we aimed to identify ancillary protein biomarkers by using complementary proteomic techniques (2D-DIGE, label-free MS). The identified candidates were immunohistochemically validated in 14 paired samples of hepatocellular carcinoma (HCC) and non-tumourous liver tissue (NT). The candidates and HepPar1/Arginase1 were afterwards tested for consistency in a large cohort of hepatocellular lesions and NT (n = 290), non-hepatocellular malignancies (n = 383) and HAC (n = 13). Eight non-redundant, differentially expressed proteins were suitable for further immunohistochemical validation and four (ABAT, BHMT, FABP1, HAOX1) for further evaluation. Sensitivity and specificity rates for HCC/HAC were as follows: HepPar1 80.2%, 94.3% / 80.2%, 46.2%; Arginase1 82%, 99.4% / 82%, 69.2%; BHMT 61.4%, 93.8% / 61.4%, 100%; ABAT 84.4%, 33.7% / 84.4%, 30.8%; FABP1 87.2%, 95% / 87.2%, 69.2%; HAOX1 95.5%, 36.3% / 95.5%, 46.2%. The best 2×/3× biomarker panels for the diagnosis of HCC consisted of Arginase1/HAOX1 and BHMT/Arginase1/HAOX1 and for HAC consisted of Arginase1/FABP1 and BHMT/Arginase1/FABP1. In summary, we successfully identified, validated and benchmarked protein biomarker candidates of hepatocellular differentiation. BHMT in particular exhibited superior diagnostic characteristics in hepatocellular lesions and specifically in HAC. BHMT is therefore a promising (panel based) biomarker candidate in the differential diagnostic process of lesions with hepatocellular aspect.

Item Purification Does Not Always Improve DIF Detection: A Counterexample with Angoff's Delta Plot

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Magis, David; Facon, Bruno

2013-01-01

Item purification is an iterative process that is often advocated as improving the identification of items affected by differential item functioning (DIF). With test-score-based DIF detection methods, item purification iteratively removes the items currently flagged as DIF from the test scores to get purified sets of items, unaffected by DIF. The…

Evaluating the quality of medical multiple-choice items created with automated processes.

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Gierl, Mark J; Lai, Hollis

2013-07-01

Computerised assessment raises formidable challenges because it requires large numbers of test items. Automatic item generation (AIG) can help address this test development problem because it yields large numbers of new items both quickly and efficiently. To date, however, the quality of the items produced using a generative approach has not been evaluated. The purpose of this study was to determine whether automatic processes yield items that meet standards of quality that are appropriate for medical testing. Quality was evaluated firstly by subjecting items created using both AIG and traditional processes to rating by a four-member expert medical panel using indicators of multiple-choice item quality, and secondly by asking the panellists to identify which items were developed using AIG in a blind review. Fifteen items from the domain of therapeutics were created in three different experimental test development conditions. The first 15 items were created by content specialists using traditional test development methods (Group 1 Traditional). The second 15 items were created by the same content specialists using AIG methods (Group 1 AIG). The third 15 items were created by a new group of content specialists using traditional methods (Group 2 Traditional). These 45 items were then evaluated for quality by a four-member panel of medical experts and were subsequently categorised as either Traditional or AIG items. Three outcomes were reported: (i) the items produced using traditional and AIG processes were comparable on seven of eight indicators of multiple-choice item quality; (ii) AIG items can be differentiated from Traditional items by the quality of their distractors, and (iii) the overall predictive accuracy of the four expert medical panellists was 42%. Items generated by AIG methods are, for the most part, equivalent to traditionally developed items from the perspective of expert medical reviewers. While the AIG method produced comparatively fewer plausible

Cross-cultural and sex differences in the Emotional Skills and Competence Questionnaire scales: Challenges of differential item functioning analyses

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Bo Molander

2009-11-01

Full Text Available University students in Croatia, Slovenia, and Sweden (N = 1129 were examined by means of the Emotional Skills and Competence Questionnaire (Takšić, 1998. Results showed a significant effect for the sex factor only on the total-score scale, women scoring higher than men, but significant effects were obtained for country, as well as for sex, on the Express and Label (EL and Perceive and Understand (PU subscales. Sweden showed higher scores than Croatia and Slovenia on the EL scale, and Slovenia showed higher scores than Croatia and Sweden on the PU scale. In subsequent analyses of differential item functioning (DIF, comparisons were carried out for pairs of countries. The analyses revealed that a large proportion of the items in the total-score scale were potentially biased, most so for the Croatian-Swedish comparison, less for the Slovenian-Swedish comparison, and least for the Croatian-Slovenian comparison. These findings give doubts about the validity of mean score differences in comparisons of countries. However, DIF analyses of sex differences within each country show very few DIF items, indicating that the ESCQ instrument works well within each cultural/linguistic setting. Possible explanations of the findings are discussed, and improvements for future studies are suggested.

A multi-level differential item functioning analysis of trends in international mathematics and science study: Potential sources of gender and minority difference among U.S. eighth graders' science achievement

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Qian, Xiaoyu

Science is an area where a large achievement gap has been observed between White and minority, and between male and female students. The science minority gap has continued as indicated by the National Assessment of Educational Progress and the Trends in International Mathematics and Science Studies (TIMSS). TIMSS also shows a gender gap favoring males emerging at the eighth grade. Both gaps continue to be wider in the number of doctoral degrees and full professorships awarded (NSF, 2008). The current study investigated both minority and gender achievement gaps in science utilizing a multi-level differential item functioning (DIF) methodology (Kamata, 2001) within fully Bayesian framework. All dichotomously coded items from TIMSS 2007 science assessment at eighth grade were analyzed. Both gender DIF and minority DIF were studied. Multi-level models were employed to identify DIF items and sources of DIF at both student and teacher levels. The study found that several student variables were potential sources of achievement gaps. It was also found that gender DIF favoring male students was more noticeable in the content areas of physics and earth science than biology and chemistry. In terms of item type, the majority of these gender DIF items were multiple choice than constructed response items. Female students also performed less well on items requiring visual-spatial ability. Minority students performed significantly worse on physics and earth science items as well. A higher percentage of minority DIF items in earth science and biology were constructed response than multiple choice items, indicating that literacy may be the cause of minority DIF. Three-level model results suggested that some teacher variables may be the cause of DIF variations from teacher to teacher. It is essential for both middle school science teachers and science educators to find instructional methods that work more effectively to improve science achievement of both female and minority students

Analysis of Nonequivalent Assessments across Different Linguistic Groups Using a Mixed Methods Approach: Understanding the Causes of Differential Item Functioning by Cognitive Interviewing

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Benítez, Isabel; Padilla, José-Luis

2014-01-01

Differential item functioning (DIF) can undermine the validity of cross-lingual comparisons. While a lot of efficient statistics for detecting DIF are available, few general findings have been found to explain DIF results. The objective of the article was to study DIF sources by using a mixed method design. The design involves a quantitative phase…

Examination of the PROMIS upper extremity item bank.

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Hung, Man; Voss, Maren W; Bounsanga, Jerry; Crum, Anthony B; Tyser, Andrew R

Clinical measurement. The psychometric properties of the PROMIS v1.2 UE item bank were tested on various samples prior to its release, but have not been fully evaluated among the orthopaedic population. This study assesses the performance of the UE item bank within the UE orthopaedic patient population. The UE item bank was administered to 1197 adult patients presenting to a tertiary orthopaedic clinic specializing in hand and UE conditions and was examined using traditional statistics and Rasch analysis. The UE item bank fits a unidimensional model (outfit MNSQ range from 0.64 to 1.70) and has adequate reliabilities (person = 0.84; item = 0.82) and local independence (item residual correlations range from -0.37 to 0.34). Only one item exhibits gender differential item functioning. Most items target low levels of function. The UE item bank is a useful clinical assessment tool. Additional items covering higher functions are needed to enhance validity. Supplemental testing is recommended for patients at higher levels of function until more high function UE items are developed. 2c. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

The emotional memory effect: differential processing or item distinctiveness?

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Schmidt, Stephen R; Saari, Bonnie

2007-12-01

A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.

Item Analysis in Introductory Economics Testing.

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Tinari, Frank D.

1979-01-01

Computerized analysis of multiple choice test items is explained. Examples of item analysis applications in the introductory economics course are discussed with respect to three objectives: to evaluate learning; to improve test items; and to help improve classroom instruction. Problems, costs and benefits of the procedures are identified. (JMD)

Cross-cultural differences in knee functional status outcomes in a polyglot society represented true disparities not biased by differential item functioning.

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Deutscher, Daniel; Hart, Dennis L; Crane, Paul K; Dickstein, Ruth

2010-12-01

Comparative effectiveness research across cultures requires unbiased measures that accurately detect clinical differences between patient groups. The purpose of this study was to assess the presence and impact of differential item functioning (DIF) in knee functional status (FS) items administered using computerized adaptive testing (CAT) as a possible cause for observed differences in outcomes between 2 cultural patient groups in a polyglot society. This study was a secondary analysis of prospectively collected data. We evaluated data from 9,134 patients with knee impairments from outpatient physical therapy clinics in Israel. Items were analyzed for DIF related to sex, age, symptom acuity, surgical history, exercise history, and language used to complete the functional survey (Hebrew versus Russian). Several items exhibited DIF, but unadjusted FS estimates and FS estimates that accounted for DIF were essentially equal (intraclass correlation coefficient [2,1]>.999). No individual patient had a difference between unadjusted and adjusted FS estimates as large as the median standard error of the unadjusted estimates. Differences between groups defined by any of the covariates considered were essentially unchanged when using adjusted instead of unadjusted FS estimates. The greatest group-level impact was <0.3% of 1 standard deviation of the unadjusted FS estimates. Complete data where patients answered all items in the scale would have been preferred for DIF analysis, but only CAT data were available. Differences in FS outcomes between groups of patients with knee impairments who answered the knee CAT in Hebrew or Russian in Israel most likely reflected true differences that may reflect societal disparities in this health outcome.

Examining Differential Math Performance by Gender and Opportunity to Learn

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Albano, Anthony D.; Rodriguez, Michael C.

2013-01-01

Although a substantial amount of research has been conducted on differential item functioning in testing, studies have focused on detecting differential item functioning rather than on explaining how or why it may occur. Some recent work has explored sources of differential functioning using explanatory and multilevel item response models. This…

The 12-item World Health Organization Disability Assessment Schedule II (WHO-DAS II: a nonparametric item response analysis

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Fernandez Ana

2010-05-01

Full Text Available Abstract Background Previous studies have analyzed the psychometric properties of the World Health Organization Disability Assessment Schedule II (WHO-DAS II using classical omnibus measures of scale quality. These analyses are sample dependent and do not model item responses as a function of the underlying trait level. The main objective of this study was to examine the effectiveness of the WHO-DAS II items and their options in discriminating between changes in the underlying disability level by means of item response analyses. We also explored differential item functioning (DIF in men and women. Methods The participants were 3615 adult general practice patients from 17 regions of Spain, with a first diagnosed major depressive episode. The 12-item WHO-DAS II was administered by the general practitioners during the consultation. We used a non-parametric item response method (Kernel-Smoothing implemented with the TestGraf software to examine the effectiveness of each item (item characteristic curves and their options (option characteristic curves in discriminating between changes in the underliying disability level. We examined composite DIF to know whether women had a higher probability than men of endorsing each item. Results Item response analyses indicated that the twelve items forming the WHO-DAS II perform very well. All items were determined to provide good discrimination across varying standardized levels of the trait. The items also had option characteristic curves that showed good discrimination, given that each increasing option became more likely than the previous as a function of increasing trait level. No gender-related DIF was found on any of the items. Conclusions All WHO-DAS II items were very good at assessing overall disability. Our results supported the appropriateness of the weights assigned to response option categories and showed an absence of gender differences in item functioning.

Use of differential item functioning (DIF analysis for bias analysis in test construction

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Marié De Beer

2004-10-01

Opsomming Waar differensiële itemfunksioneringsprosedures (DIF-prosedures vir itemontleding gebaseer op itemresponsteorie (IRT tydens toetskonstruksie gebruik word, is dit moontlik om itemkarakteristiekekrommes vir dieselfde item vir verskillende subgroepe voor te stel. Hierdie krommes dui aan hoe elke item vir die verskillende subgroepe op verskillende vermoënsvlakke te funksioneer. DIF word aangetoon deur die area tussen die krommes. DIF is in die konstruksie van die 'Learning Potential Computerised Adaptive test (LPCAT' gebruik om die items te identifiseer wat sydigheid ten opsigte van geslag, kultuur, taal of opleidingspeil geopenbaar het. Items wat ’n voorafbepaalde vlak van DIF oorskry het, is uit die finale itembank weggelaat, ongeag die subgroep wat bevoordeel of benadeel is. Die proses en resultate van die DIF-ontleding word bespreek.

Item response theory analyses of the Delis-Kaplan Executive Function System card sorting subtest.

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Spencer, Mercedes; Cho, Sun-Joo; Cutting, Laurie E

2018-02-02

In the current study, we examined the dimensionality of the 16-item Card Sorting subtest of the Delis-Kaplan Executive Functioning System assessment in a sample of 264 native English-speaking children between the ages of 9 and 15 years. We also tested for measurement invariance for these items across age and gender groups using item response theory (IRT). Results of the exploratory factor analysis indicated that a two-factor model that distinguished between verbal and perceptual items provided the best fit to the data. Although the items demonstrated measurement invariance across age groups, measurement invariance was violated for gender groups, with two items demonstrating differential item functioning for males and females. Multigroup analysis using all 16 items indicated that the items were more effective for individuals whose IRT scale scores were relatively high. A single-group explanatory IRT model using 14 non-differential item functioning items showed that for perceptual ability, females scored higher than males and that scores increased with age for both males and females; for verbal ability, the observed increase in scores across age differed for males and females. The implications of these findings are discussed.

Validation of a mobility item bank for older patients in primary care.

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Cabrero-García, Julio; Ramos-Pichardo, Juan Diego; Muñoz-Mendoza, Carmen Luz; Cabañero-Martínez, María José; González-Llopis, Lorena; Reig-Ferrer, Abilio

2012-12-05

To develop and validate an item bank to measure mobility in older people in primary care and to analyse differential item functioning (DIF) and differential bundle functioning (DBF) by sex. A pool of 48 mobility items was administered by interview to 593 older people attending primary health care practices. The pool contained four domains based on the International Classification of Functioning: changing and maintaining body position, carrying, lifting and pushing, walking and going up and down stairs. The Late Life Mobility item bank consisted of 35 items, and measured with a reliability of 0.90 or more across the full spectrum of mobility, except at the higher end of better functioning. No evidence was found of non-uniform DIF but uniform DIF was observed, mainly for items in the changing and maintaining body position and carrying, lifting and pushing domains. The walking domain did not display DBF, but the other three domains did, principally the carrying, lifting and pushing items. During the design and validation of an item bank to measure mobility in older people, we found that strength (carrying, lifting and pushing) items formed a secondary dimension that produced DBF. More research is needed to determine how best to include strength items in a mobility measure, or whether it would be more appropriate to design separate measures for each construct.

Detecting DIF in Polytomous Items Using MACS, IRT and Ordinal Logistic Regression

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Elosua, Paula; Wells, Craig

2013-01-01

The purpose of the present study was to compare the Type I error rate and power of two model-based procedures, the mean and covariance structure model (MACS) and the item response theory (IRT), and an observed-score based procedure, ordinal logistic regression, for detecting differential item functioning (DIF) in polytomous items. A simulation…

Lawton IADL scale in dementia: can item response theory make it more informative?

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McGrory, Sarah; Shenkin, Susan D; Austin, Elizabeth J; Starr, John M

2014-07-01

impairment of functional abilities represents a crucial component of dementia diagnosis. Current functional measures rely on the traditional aggregate method of summing raw scores. While this summary score provides a quick representation of a person's ability, it disregards useful information on the item level. to use item response theory (IRT) methods to increase the interpretive power of the Lawton Instrumental Activities of Daily Living (IADL) scale by establishing a hierarchy of item 'difficulty' and 'discrimination'. this cross-sectional study applied IRT methods to the analysis of IADL outcomes. Participants were 202 members of the Scottish Dementia Research Interest Register (mean age = 76.39, range = 56-93, SD = 7.89 years) with complete itemised data available. a Mokken scale with good reliability (Molenaar Sijtsama statistic 0.79) was obtained, satisfying the IRT assumption that the items comprise a single unidimensional scale. The eight items in the scale could be placed on a hierarchy of 'difficulty' (H coefficient = 0.55), with 'Shopping' being the most 'difficult' item and 'Telephone use' being the least 'difficult' item. 'Shopping' was the most discriminatory item differentiating well between patients of different levels of ability. IRT methods are capable of providing more information about functional impairment than a summed score. 'Shopping' and 'Telephone use' were identified as items that reveal key information about a patient's level of ability, and could be useful screening questions for clinicians. © The Author 2013. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@ oup.com.

Fitting a Mixture Rasch Model to English as a Foreign Language Listening Tests: The Role of Cognitive and Background Variables in Explaining Latent Differential Item Functioning

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Aryadoust, Vahid

2015-01-01

The present study uses a mixture Rasch model to examine latent differential item functioning in English as a foreign language listening tests. Participants (n = 250) took a listening and lexico-grammatical test and completed the metacognitive awareness listening questionnaire comprising problem solving (PS), planning and evaluation (PE), mental…

5 CFR 591.212 - How does OPM select survey items?

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2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false How does OPM select survey items? 591.212 Section 591.212 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ALLOWANCES AND DIFFERENTIALS Cost-of-Living Allowance and Post Differential-Nonforeign Areas Cost-Of-Living...

Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

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Lix, Lisa M; Wu, Xiuyun; Hopman, Wilma; Mayo, Nancy; Sajobi, Tolulope T; Liu, Juxin; Prior, Jerilynn C; Papaioannou, Alexandra; Josse, Robert G; Towheed, Tanveer E; Davison, K Shawn; Sawatzky, Richard

2016-01-01

Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36), can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF), which arises when population sub-groups with the same underlying (i.e., latent) level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF) and mental health (MH) sub-scale items in a Canadian population-based sample. Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos), which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC) method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health) produced estimates of the magnitude of DIF effects. The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size. SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

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Lisa M Lix

Full Text Available Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36, can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF, which arises when population sub-groups with the same underlying (i.e., latent level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF and mental health (MH sub-scale items in a Canadian population-based sample.Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos, which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health produced estimates of the magnitude of DIF effects.The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size.SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

The Protective Behavioral Strategies for Marijuana Scale: Further examination using item response theory.

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Pedersen, Eric R; Huang, Wenjing; Dvorak, Robert D; Prince, Mark A; Hummer, Justin F

2017-08-01

Given recent state legislation legalizing marijuana for recreational purposes and majority popular opinion favoring these laws, we developed the Protective Behavioral Strategies for Marijuana scale (PBSM) to identify strategies that may mitigate the harms related to marijuana use among those young people who choose to use the drug. In the current study, we expand on the initial exploratory study of the PBSM to further validate the measure with a large and geographically diverse sample (N = 2,117; 60% women, 30% non-White) of college students from 11 different universities across the United States. We sought to develop a psychometrically sound item bank for the PBSM and to create a short assessment form that minimizes respondent burden and time. Quantitative item analyses, including exploratory and confirmatory factor analyses with item response theory (IRT) and evaluation of differential item functioning (DIF), revealed an item bank of 36 items that was examined for unidimensionality and good content coverage, as well as a short form of 17 items that is free of bias in terms of gender (men vs. women), race (White vs. non-White), ethnicity (Hispanic vs. non-Hispanic), and recreational marijuana use legal status (state recreational marijuana was legal for 25.5% of participants). We also provide a scoring table for easy transformation from sum scores to IRT scale scores. The PBSM item bank and short form associated strongly and negatively with past month marijuana use and consequences. The measure may be useful to researchers and clinicians conducting intervention and prevention programs with young adults. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Consistent Differential Expression Pattern (CDEP) on microarray to identify genes related to metastatic behavior.

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Tsoi, Lam C; Qin, Tingting; Slate, Elizabeth H; Zheng, W Jim

2011-11-11

To utilize the large volume of gene expression information generated from different microarray experiments, several meta-analysis techniques have been developed. Despite these efforts, there remain significant challenges to effectively increasing the statistical power and decreasing the Type I error rate while pooling the heterogeneous datasets from public resources. The objective of this study is to develop a novel meta-analysis approach, Consistent Differential Expression Pattern (CDEP), to identify genes with common differential expression patterns across different datasets. We combined False Discovery Rate (FDR) estimation and the non-parametric RankProd approach to estimate the Type I error rate in each microarray dataset of the meta-analysis. These Type I error rates from all datasets were then used to identify genes with common differential expression patterns. Our simulation study showed that CDEP achieved higher statistical power and maintained low Type I error rate when compared with two recently proposed meta-analysis approaches. We applied CDEP to analyze microarray data from different laboratories that compared transcription profiles between metastatic and primary cancer of different types. Many genes identified as differentially expressed consistently across different cancer types are in pathways related to metastatic behavior, such as ECM-receptor interaction, focal adhesion, and blood vessel development. We also identified novel genes such as AMIGO2, Gem, and CXCL11 that have not been shown to associate with, but may play roles in, metastasis. CDEP is a flexible approach that borrows information from each dataset in a meta-analysis in order to identify genes being differentially expressed consistently. We have shown that CDEP can gain higher statistical power than other existing approaches under a variety of settings considered in the simulation study, suggesting its robustness and insensitivity to data variation commonly associated with microarray

Gender differences in national assessment of educational progress science items: What does i don't know really mean?

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Linn, Marcia C.; de Benedictis, Tina; Delucchi, Kevin; Harris, Abigail; Stage, Elizabeth

The National Assessment of Educational Progress Science Assessment has consistently revealed small gender differences on science content items but not on science inquiry items. This assessment differs from others in that respondents can choose I don't know rather than guessing. This paper examines explanations for the gender differences including (a) differential prior instruction, (b) differential response to uncertainty and use of the I don't know response, (c) differential response to figurally presented items, and (d) different attitudes towards science. Of these possible explanations, the first two received support. Females are more likely to use the I don't know response, especially for items with physical science content or masculine themes such as football. To ameliorate this situation we need more effective science instruction and more gender-neutral assessment items.

Identifying States along the Hematopoietic Stem Cell Differentiation Hierarchy with Single Cell Specificity via Raman Spectroscopy.

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Ilin, Yelena; Choi, Ji Sun; Harley, Brendan A C; Kraft, Mary L

2015-11-17

A major challenge for expanding specific types of hematopoietic cells ex vivo for the treatment of blood cell pathologies is identifying the combinations of cellular and matrix cues that direct hematopoietic stem cells (HSC) to self-renew or differentiate into cell populations ex vivo. Microscale screening platforms enable minimizing the number of rare HSCs required to screen the effects of numerous cues on HSC fate decisions. These platforms create a strong demand for label-free methods that accurately identify the fate decisions of individual hematopoietic cells at specific locations on the platform. We demonstrate the capacity to identify discrete cells along the HSC differentiation hierarchy via multivariate analysis of Raman spectra. Notably, cell state identification is accurate for individual cells and independent of the biophysical properties of the functionalized polyacrylamide gels upon which these cells are cultured. We report partial least-squares discriminant analysis (PLS-DA) models of single cell Raman spectra enable identifying four dissimilar hematopoietic cell populations across the HSC lineage specification. Successful discrimination was obtained for a population enriched for long-term repopulating HSCs (LT-HSCs) versus their more differentiated progeny, including closely related short-term repopulating HSCs (ST-HSCs) and fully differentiated lymphoid (B cells) and myeloid (granulocytes) cells. The lineage-specific differentiation states of cells from these four subpopulations were accurately identified independent of the stiffness of the underlying biomaterial substrate, indicating subtle spectral variations that discriminated these populations were not masked by features from the culture substrate. This approach enables identifying the lineage-specific differentiation stages of hematopoietic cells on biomaterial substrates of differing composition and may facilitate correlating hematopoietic cell fate decisions with the extrinsic cues that

Psychometric properties of the Triarchic Psychopathy Measure: An item response theory approach.

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Shou, Yiyun; Sellbom, Martin; Xu, Jing

2018-05-01

There is cumulative evidence for the cross-cultural validity of the Triarchic Psychopathy Measure (TriPM; Patrick, 2010) among non-Western populations. Recent studies using correlational and regression analyses show promising construct validity of the TriPM in Chinese samples. However, little is known about the efficiency of items in TriPM in assessing the proposed latent traits. The current study evaluated the psychometric properties of the Chinese TriPM at the item level using item response theory analyses. It also examined the measurement invariance of the TriPM between the Chinese and the U.S. student samples by applying differential item functioning analyses under the item response theory framework. The results supported the unidimensional nature of the Disinhibition and Meanness scales. Both scales had a greater level of precision in the respective underlying constructs at the positive ends. The two scales, however, had several items that were weakly associated with their respective latent traits in the Chinese student sample. Boldness, on the other hand, was found to be multidimensional, and reflected a more normally distributed range of variation. The examination of measurement bias via differential item functioning analyses revealed that a number of items of the TriPM were not equivalent across the Chinese and the U.S. Some modification and adaptation of items might be considered for improving the precision of the TriPM for Chinese participants. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Factor Structure and Reliability of Test Items for Saudi Teacher Licence Assessment

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Alsadaawi, Abdullah Saleh

2017-01-01

The Saudi National Assessment Centre administers the Computer Science Teacher Test for teacher certification. The aim of this study is to explore gender differences in candidates' scores, and investigate dimensionality, reliability, and differential item functioning using confirmatory factor analysis and item response theory. The confirmatory…

Data Visualization of Item-Total Correlation by Median Smoothing

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Chong Ho Yu

2016-02-01

Full Text Available This paper aims to illustrate how data visualization could be utilized to identify errors prior to modeling, using an example with multi-dimensional item response theory (MIRT. MIRT combines item response theory and factor analysis to identify a psychometric model that investigates two or more latent traits. While it may seem convenient to accomplish two tasks by employing one procedure, users should be cautious of problematic items that affect both factor analysis and IRT. When sample sizes are extremely large, reliability analyses can misidentify even random numbers as meaningful patterns. Data visualization, such as median smoothing, can be used to identify problematic items in preliminary data cleaning.

Link-based quantitative methods to identify differentially coexpressed genes and gene Pairs

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Ye Zhi-Qiang

2011-08-01

Full Text Available Abstract Background Differential coexpression analysis (DCEA is increasingly used for investigating the global transcriptional mechanisms underlying phenotypic changes. Current DCEA methods mostly adopt a gene connectivity-based strategy to estimate differential coexpression, which is characterized by comparing the numbers of gene neighbors in different coexpression networks. Although it simplifies the calculation, this strategy mixes up the identities of different coexpression neighbors of a gene, and fails to differentiate significant differential coexpression changes from those trivial ones. Especially, the correlation-reversal is easily missed although it probably indicates remarkable biological significance. Results We developed two link-based quantitative methods, DCp and DCe, to identify differentially coexpressed genes and gene pairs (links. Bearing the uniqueness of exploiting the quantitative coexpression change of each gene pair in the coexpression networks, both methods proved to be superior to currently popular methods in simulation studies. Re-mining of a publicly available type 2 diabetes (T2D expression dataset from the perspective of differential coexpression analysis led to additional discoveries than those from differential expression analysis. Conclusions This work pointed out the critical weakness of current popular DCEA methods, and proposed two link-based DCEA algorithms that will make contribution to the development of DCEA and help extend it to a broader spectrum.

Perturbation-expression analysis identifies RUNX1 as a regulator of human mammary stem cell differentiation.

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Ethan S Sokol

2015-04-01

Full Text Available The search for genes that regulate stem cell self-renewal and differentiation has been hindered by a paucity of markers that uniquely label stem cells and early progenitors. To circumvent this difficulty we have developed a method that identifies cell-state regulators without requiring any markers of differentiation, termed Perturbation-Expression Analysis of Cell States (PEACS. We have applied this marker-free approach to screen for transcription factors that regulate mammary stem cell differentiation in a 3D model of tissue morphogenesis and identified RUNX1 as a stem cell regulator. Inhibition of RUNX1 expanded bipotent stem cells and blocked their differentiation into ductal and lobular tissue rudiments. Reactivation of RUNX1 allowed exit from the bipotent state and subsequent differentiation and mammary morphogenesis. Collectively, our findings show that RUNX1 is required for mammary stem cells to exit a bipotent state, and provide a new method for discovering cell-state regulators when markers are not available.

Assessment of Preference for Edible and Leisure Items in Individuals with Dementia

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Ortega, Javier Virues; Iwata, Brian A.; Nogales-Gonzalez, Celia; Frades, Belen

2012-01-01

We conducted 2 studies on reinforcer preference in patients with dementia. Results of preference assessments yielded differential selections by 14 participants. Unlike prior studies with individuals with intellectual disabilities, all participants showed a noticeable preference for leisure items over edible items. Results of a subsequent analysis…

Work ability as prognostic risk marker of disability pension : Single-item work ability score versus multi-item work ability index

NARCIS (Netherlands)

Roelen, C.A.M.; Rhenen, van W.; Groothoff, J.W.; Klink, van der J.J.L.; Twisk, W.R.; Heymans, M.W.

2014-01-01

Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP.

VMAT2 identified as a regulator of late-stage β-cell differentiation.

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Sakano, Daisuke; Shiraki, Nobuaki; Kikawa, Kazuhide; Yamazoe, Taiji; Kataoka, Masateru; Umeda, Kahoko; Araki, Kimi; Mao, Di; Matsumoto, Shirou; Nakagata, Naomi; Andersson, Olov; Stainier, Didier; Endo, Fumio; Kume, Kazuhiko; Uesugi, Motonari; Kume, Shoen

2014-02-01

Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic β cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying β-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated β-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into β cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived β cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of β-cell differentiation and its application to a cost-effective production of functional β cells for cell therapy.

Work ability as prognostic risk marker of disability pension: single-item work ability score versus multi-item work ability index

NARCIS (Netherlands)

Roelen, C.A.M.; van Rhenen, W.; Groothoff, J.W.; van der Klink, J.J.L.; Twisk, J.W.R.; Heymans, M.W.

2014-01-01

Objectives Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP. Methods This

Work ability as prognostic risk marker of disability pension : single-item work ability score versus multi-item work ability index

NARCIS (Netherlands)

Roelen, Corne A. M.; van Rhenen, Willem; Groothoff, Johan W.; van der Klink, Jac J. L.; Twisk, Jos W. R.; Heymans, Martijn W.

Objectives Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP. Methods This

The processing of inter-item relations as a moderating factor of retrieval-induced forgetting

OpenAIRE

Tempel, Tobias; Wippich, Werner

2012-01-01

We investigated influences of item generation and emotional valence on retrieval-induced forgetting. Drawing on postulates of the three-factor theory of generation effects, generation tasks differentially affecting the processing of inter-item relations were applied. Whereas retrieval-induced forgetting of freely generated items was moderated by the emotional valence as well as retrieval-induced forgetting of read items, even though in the reverse direction (Experiment 1), fragment completion...

Exploring differential item functioning (DIF) with the Rasch model: a comparison of gender differences on eighth grade science items in the United States and Spain.

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Babiar, Tasha Calvert

2011-01-01

Traditionally, women and minorities have not been fully represented in science and engineering. Numerous studies have attributed these differences to gaps in science achievement as measured by various standardized tests. Rather than describe mean group differences in science achievement across multiple cultures, this study focused on an in-depth item-level analysis across two countries: Spain and the United States. This study investigated eighth-grade gender differences on science items across the two countries. A secondary purpose of the study was to explore the nature of gender differences using the many-faceted Rasch Model as a way to estimate gender DIF. A secondary analysis of data from the Third International Mathematics and Science Study (TIMSS) was used to address three questions: 1) Does gender DIF in science achievement exist? 2) Is there a relationship between gender DIF and characteristics of the science items? 3) Do the relationships between item characteristics and gender DIF in science items replicate across countries. Participants included 7,087 eight grade students from the United States and 3,855 students from Spain who participated in TIMSS. The Facets program (Linacre and Wright, 1992) was used to estimate gender DIF. The results of the analysis indicate that the content of the item seemed to be related to gender DIF. The analysis also suggests that there is a relationship between gender DIF and item format. No pattern of gender DIF related to cognitive demand was found. The general pattern of gender DIF was similar across the two countries used in the analysis. The strength of item-level analysis as opposed to group mean difference analysis is that gender differences can be detected at the item level, even when no mean differences can be detected at the group level.

Robust Nonnegative Matrix Factorization via Joint Graph Laplacian and Discriminative Information for Identifying Differentially Expressed Genes

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Ling-Yun Dai

2017-01-01

Full Text Available Differential expression plays an important role in cancer diagnosis and classification. In recent years, many methods have been used to identify differentially expressed genes. However, the recognition rate and reliability of gene selection still need to be improved. In this paper, a novel constrained method named robust nonnegative matrix factorization via joint graph Laplacian and discriminative information (GLD-RNMF is proposed for identifying differentially expressed genes, in which manifold learning and the discriminative label information are incorporated into the traditional nonnegative matrix factorization model to train the objective matrix. Specifically, L2,1-norm minimization is enforced on both the error function and the regularization term which is robust to outliers and noise in gene data. Furthermore, the multiplicative update rules and the details of convergence proof are shown for the new model. The experimental results on two publicly available cancer datasets demonstrate that GLD-RNMF is an effective method for identifying differentially expressed genes.

Molecular analysis of expansion, differentiation, and growth factor treatment of human chondrocytes identifies differentiation markers and growth-related genes.

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Benz, Karin; Breit, Stephen; Lukoschek, Martin; Mau, Hans; Richter, Wiltrud

2002-04-26

This study is intended to optimise expansion and differentiation of cultured human chondrocytes by growth factor application and to identify molecular markers to monitor their differentiation state. We dissected the molecular consequences of matrix release, monolayer, and 3D-alginate culture, growth factor optimised expansion, and re-differentiation protocols by gene expression analysis. Among 19 common cartilage molecules assessed by cDNA array, six proved best to monitor differentiation. Instant down-regulation at release of cells from the matrix was strongest for COL 2A1, fibromodulin, and PRELP while LUM, CHI3L1, and CHI3L2 were expansion-related. Both gene sets reflected the physiologic effects of the most potent growth-inducing (PDGF-BB) and proteoglycan-inducing (BMP-4) factors. Only CRTAC1 expression correlated with 2D/3D switches while the molecular phenotype of native chondrocytes was not restored. The markers and optimised protocols we suggest can help to improve cell therapy of cartilage defects and chondrocyte differentiation from stem cell sources.

Compreensão da leitura: análise do funcionamento diferencial dos itens de um Teste de Cloze Reading comprehension: differential item functioning analysis of a Cloze Test

Directory of Open Access Journals (Sweden)

Katya Luciane Oliveira

2012-01-01

Full Text Available Este estudo teve por objetivos investigar o ajuste de um Teste de Cloze ao modelo Rasch e avaliar a dificuldade na resposta ao item em razão do gênero das pessoas (DIF. Participaram da pesquisa 573 alunos das 5ª a 8ª séries do ensino fundamental de escolas públicas estaduais dos estados de São Paulo e Minas Gerais. O teste de Cloze foi aplicado de forma coletiva. A análise do instrumento evidenciou um bom ajuste ao modelo Rasch, bem como os itens foram respondidos conforme o padrão esperado, demonstrando um bom ajuste, também. Quanto ao DIF, apenas três itens indicaram diferenciar o gênero. Com base nos dados, identificou-se que houve equilíbrio nas respostas dadas pelos meninos e meninas.The objectives of the present study were to investigate the adaptation of a Cloze test to the Rasch Model as well as to evaluate the Differential Item Functioning (DIF in relation to gender. The sample was composed by 573 students from 5th to 8th grades of public schools in the state of São Paulo. The cloze test was applied collectively. The analysis of the instrument revealed its adaptation to Rash Model and that the items were responded according to the expected pattern, showing good adjustment, as well. Regarding DIF, only three items were differentiated by gender. Based on the data, results indicated a balance in the answers given by boys and girls.

Differential membrane proteomics using 18O-labeling to identify biomarkers for cholangiocarcinoma

DEFF Research Database (Denmark)

Kristiansen, Troels Zakarias; Harsha, H C; Grønborg, Mads

2008-01-01

Quantitative proteomic methodologies allow profiling of hundreds to thousands of proteins in a high-throughput fashion. This approach is increasingly applied to cancer biomarker discovery to identify proteins that are differentially regulated in cancers. Fractionation of protein samples based...

Item Response Theory Analyses of the Cambridge Face Memory Test (CFMT)

Science.gov (United States)

Cho, Sun-Joo; Wilmer, Jeremy; Herzmann, Grit; McGugin, Rankin; Fiset, Daniel; Van Gulick, Ana E.; Ryan, Katie; Gauthier, Isabel

2014-01-01

We evaluated the psychometric properties of the Cambridge face memory test (CFMT; Duchaine & Nakayama, 2006). First, we assessed the dimensionality of the test with a bi-factor exploratory factor analysis (EFA). This EFA analysis revealed a general factor and three specific factors clustered by targets of CFMT. However, the three specific factors appeared to be minor factors that can be ignored. Second, we fit a unidimensional item response model. This item response model showed that the CFMT items could discriminate individuals at different ability levels and covered a wide range of the ability continuum. We found the CFMT to be particularly precise for a wide range of ability levels. Third, we implemented item response theory (IRT) differential item functioning (DIF) analyses for each gender group and two age groups (Age ≤ 20 versus Age > 21). This DIF analysis suggested little evidence of consequential differential functioning on the CFMT for these groups, supporting the use of the test to compare older to younger, or male to female, individuals. Fourth, we tested for a gender difference on the latent facial recognition ability with an explanatory item response model. We found a significant but small gender difference on the latent ability for face recognition, which was higher for women than men by 0.184, at age mean 23.2, controlling for linear and quadratic age effects. Finally, we discuss the practical considerations of the use of total scores versus IRT scale scores in applications of the CFMT. PMID:25642930

Item Response Theory Applied to Factors Affecting the Patient Journey Towards Hearing Rehabilitation

Science.gov (United States)

Chenault, Michelene; Berger, Martijn; Kremer, Bernd; Anteunis, Lucien

2016-01-01

To develop a tool for use in hearing screening and to evaluate the patient journey towards hearing rehabilitation, responses to the hearing aid rehabilitation questionnaire scales aid stigma, pressure, and aid unwanted addressing respectively hearing aid stigma, experienced pressure from others; perceived hearing aid benefit were evaluated with item response theory. The sample was comprised of 212 persons aged 55 years or more; 63 were hearing aid users, 64 with and 85 persons without hearing impairment according to guidelines for hearing aid reimbursement in the Netherlands. Bias was investigated relative to hearing aid use and hearing impairment within the differential test functioning framework. Items compromising model fit or demonstrating differential item functioning were dropped. The aid stigma scale was reduced from 6 to 4, the pressure scale from 7 to 4, and the aid unwanted scale from 5 to 4 items. This procedure resulted in bias-free scales ready for screening purposes and application to further understand the help-seeking process of the hearing impaired. PMID:28028428

Constructing the 32-item Fitness-to-Drive Screening Measure.

Science.gov (United States)

Medhizadah, Shabnam; Classen, Sherrilene; Johnson, Andrew M

2018-04-01

The Fitness-to-Drive Screening Measure © (FTDS) enables proxies to identify at-risk older drivers via 54 driving-related items, but may be too lengthy for widespread uptake. We reduced the number of items in the FTDS and validated the shorter measure, using 200 caregiver responses. Exploratory factor analysis and classical test theory techniques were used to determine the most interpretable factor model and the minimum number of items to be used for predicting fitness to drive. The extent to which the shorter FTDS predicted the results of the 54-item FTDS was evaluated through correlational analysis. A three-factor model best represented the empirical data. Classical test theory techniques lead to the development of the 32-item FTDS. The 32-item FTDS was highly correlated ( r = .99, p = .05) with the FTDS. The 32-item FTDS may provide raters with a faster and more efficient way to identify at-risk older drivers.

Gender Differences in Figural Matrices: The Moderating Role of Item Design Features

Science.gov (United States)

Arendasy, Martin E.; Sommer, Markus

2012-01-01

There is a heated debate on whether observed gender differences in some figural matrices in adults can be attributed to gender differences in inductive reasoning/G[subscript f] or differential item functioning and/or test bias. Based on previous studies we hypothesized that three specific item design features moderate the effect size of the gender…

Validation of MIMGO: a method to identify differentially expressed GO terms in a microarray dataset

OpenAIRE

Yamada, Yoichi; Sawada, Hiroki; Hirotani, Ken-ichi; Oshima, Masanobu; Satou, Kenji

2012-01-01

Abstract Background We previously proposed an algorithm for the identification of GO terms that commonly annotate genes whose expression is upregulated or downregulated in some microarray data compared with in other microarray data. We call these “differentially expressed GO terms” and have named the algorithm “matrix-assisted identification method of differentially expressed GO terms” (MIMGO). MIMGO can also identify microarray data in which genes annotated with a differentially expressed GO...

Measurement equivalence of the KINDL questionnaire across child self-reports and parent proxy-reports: a comparison between item response theory and ordinal logistic regression.

Science.gov (United States)

Jafari, Peyman; Sharafi, Zahra; Bagheri, Zahra; Shalileh, Sara

2014-06-01

Measurement equivalence is a necessary assumption for meaningful comparison of pediatric quality of life rated by children and parents. In this study, differential item functioning (DIF) analysis is used to examine whether children and their parents respond consistently to the items in the KINDer Lebensqualitätsfragebogen (KINDL; in German, Children Quality of Life Questionnaire). Two DIF detection methods, graded response model (GRM) and ordinal logistic regression (OLR), were applied for comparability. The KINDL was completed by 1,086 school children and 1,061 of their parents. While the GRM revealed that 12 out of the 24 items were flagged with DIF, the OLR identified 14 out of the 24 items with DIF. Seven items with DIF and five items without DIF were common across the two methods, yielding a total agreement rate of 50 %. This study revealed that parent proxy-reports cannot be used as a substitute for a child's ratings in the KINDL.

Differential Aspartate Usage Identifies a Subset of Cancer Cells Particularly Dependent on OGDH

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Eric L. Allen

2016-10-01

Full Text Available Although aberrant metabolism in tumors has been well described, the identification of cancer subsets with particular metabolic vulnerabilities has remained challenging. Here, we conducted an siRNA screen focusing on enzymes involved in the tricarboxylic acid (TCA cycle and uncovered a striking range of cancer cell dependencies on OGDH, the E1 subunit of the alpha-ketoglutarate dehydrogenase complex. Using an integrative metabolomics approach, we identified differential aspartate utilization, via the malate-aspartate shuttle, as a predictor of whether OGDH is required for proliferation in 3D culture assays and for the growth of xenograft tumors. These findings highlight an anaplerotic role of aspartate and, more broadly, suggest that differential nutrient utilization patterns can identify subsets of cancers with distinct metabolic dependencies for potential pharmacological intervention.

INVESTIGATION OF MIS ITEM 011589A AND 3013 CONTAINERS HAVING SIMILAR CHARACTERISTICS

Energy Technology Data Exchange (ETDEWEB)

Friday, G

2006-08-23

Recent testing has identified the presence of hydrogen and oxygen in MIS Item 011589A. This isolated observation has effectuated concern regarding the potential for flammable gas mixtures in containers in the storage inventory. This study examines the known physicochemical characteristics of MIS Item 011589A and queries the ISP Database for items that are most similar or potentially similar. Items identified as most similar are believed to have the highest probability of being chemically and structurally identical to MIS Item 011589A. Items identified as potentially like MIS Item 011589A have some attributes in common, have the potential to generate gases, but have a lower probability of having similar gas generating characteristics. MIS Item 011589A is an oxide that was generated prior to 1990 at Rocky Flats in Building 707. It was associated with foundry processing and had an actinide assay of approximately 77%. Prompt gamma analysis of MIS Item 011589A indicated the presence of chloride, fluorine, magnesium, sodium, and aluminum. Queries based on MIS representation classification and process of origin were applied to the ISP Database. Evaluation criteria included binning classification (i.e., innocuous, pressure, or pressure and corrosion), availability of prompt gamma analyses, presence of chlorine and magnesium, percentage of chlorine by weight, peak ratios (i.e., Na:Cl and Mg:Na), moisture, and percent assay. These queries identified 15 items that were most similar and 106 items that were potentially like MIS Item 011589A. Although these queries identified containers that could potentially generate flammable gases, verification and confirmation can only be accomplished by destructive evaluation and testing of containers from the storage inventory.

Item validity vs. item discrimination index: a redundancy?

Science.gov (United States)

Panjaitan, R. L.; Irawati, R.; Sujana, A.; Hanifah, N.; Djuanda, D.

2018-03-01

In several literatures about evaluation and test analysis, it is common to find that there are calculations of item validity as well as item discrimination index (D) with different formula for each. Meanwhile, other resources said that item discrimination index could be obtained by calculating the correlation between the testee’s score in a particular item and the testee’s score on the overall test, which is actually the same concept as item validity. Some research reports, especially undergraduate theses tend to include both item validity and item discrimination index in the instrument analysis. It seems that these concepts might overlap for both reflect the test quality on measuring the examinees’ ability. In this paper, examples of some results of data processing on item validity and item discrimination index were compared. It would be discussed whether item validity and item discrimination index can be represented by one of them only or it should be better to present both calculations for simple test analysis, especially in undergraduate theses where test analyses were included.

Using response-time constraints in item selection to control for differential speededness in computerized adaptive testing

NARCIS (Netherlands)

van der Linden, Willem J.; Scrams, David J.; Schnipke, Deborah L.

2003-01-01

This paper proposes an item selection algorithm that can be used to neutralize the effect of time limits in computer adaptive testing. The method is based on a statistical model for the response-time distributions of the test takers on the items in the pool that is updated each time a new item has

Development and Evaluation of the PROMIS® Pediatric Positive Affect Item Bank, Child-Report and Parent-Proxy Editions.

Science.gov (United States)

Forrest, Christopher B; Ravens-Sieberer, Ulrike; Devine, Janine; Becker, Brandon D; Teneralli, Rachel; Moon, JeanHee; Carle, Adam; Tucker, Carole A; Bevans, Katherine B

2018-03-01

The purpose of this study is to describe the psychometric evaluation and item response theory calibration of the PROMIS Pediatric Positive Affect item bank, child-report and parent-proxy editions. The initial item pool comprising 53 items, previously developed using qualitative methods, was administered to 1,874 children 8-17 years old and 909 parents of children 5-17 years old. Analyses included descriptive statistics, reliability, factor analysis, differential item functioning, and construct validity. A total of 14 items were deleted, because of poor psychometric performance, and an 8-item short form constructed from the remaining 39 items was administered to a national sample of 1,004 children 8-17 years old, and 1,306 parents of children 5-17 years old. The combined sample was used in item response theory (IRT) calibration analyses. The final item bank appeared unidimensional, the items appeared locally independent, and the items were free from differential item functioning. The scales showed excellent reliability and convergent and discriminant validity. Positive affect decreased with children's age and was lower for those with a special health care need. After IRT calibration, we found that 4 and 8 item short forms had a high degree of precision (reliability) across a wide range of the latent trait (>4 SD units). The PROMIS Pediatric Positive Affect item bank and its short forms provide an efficient, precise, and valid assessment of positive affect in children and youth.

An item response theory analysis of the Executive Interview and development of the EXIT8: A Project FRONTIER Study.

Science.gov (United States)

Jahn, Danielle R; Dressel, Jeffrey A; Gavett, Brandon E; O'Bryant, Sid E

2015-01-01

The Executive Interview (EXIT25) is an effective measure of executive dysfunction, but may be inefficient due to the time it takes to complete 25 interview-based items. The current study aimed to examine psychometric properties of the EXIT25, with a specific focus on determining whether a briefer version of the measure could comprehensively assess executive dysfunction. The current study applied a graded response model (a type of item response theory model for polytomous categorical data) to identify items that were most closely related to the underlying construct of executive functioning and best discriminated between varying levels of executive functioning. Participants were 660 adults ages 40 to 96 years living in West Texas, who were recruited through an ongoing epidemiological study of rural health and aging, called Project FRONTIER. The EXIT25 was the primary measure examined. Participants also completed the Trail Making Test and Controlled Oral Word Association Test, among other measures, to examine the convergent validity of a brief form of the EXIT25. Eight items were identified that provided the majority of the information about the underlying construct of executive functioning; total scores on these items were associated with total scores on other measures of executive functioning and were able to differentiate between cognitively healthy, mildly cognitively impaired, and demented participants. In addition, cutoff scores were recommended based on sensitivity and specificity of scores. A brief, eight-item version of the EXIT25 may be an effective and efficient screening for executive dysfunction among older adults.

Losing Items in the Psychogeriatric Nursing Home

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J. van Hoof PhD

2016-09-01

Full Text Available Introduction: Losing items is a time-consuming occurrence in nursing homes that is ill described. An explorative study was conducted to investigate which items got lost by nursing home residents, and how this affects the residents and family caregivers. Method: Semi-structured interviews and card sorting tasks were conducted with 12 residents with early-stage dementia and 12 family caregivers. Thematic analysis was applied to the outcomes of the sessions. Results: The participants stated that numerous personal items and assistive devices get lost in the nursing home environment, which had various emotional, practical, and financial implications. Significant amounts of time are spent on trying to find items, varying from 1 hr up to a couple of weeks. Numerous potential solutions were identified by the interviewees. Discussion: Losing items often goes together with limitations to the participation of residents. Many family caregivers are reluctant to replace lost items, as these items may get lost again.

Item response theory applied to factors affecting the patient journey towards hearing rehabilitation

Directory of Open Access Journals (Sweden)

Michelene Chenault

2016-11-01

Full Text Available To develop a tool for use in hearing screening and to evaluate the patient journey towards hearing rehabilitation, responses to the hearing aid rehabilitation questionnaire scales aid stigma, pressure, and aid unwanted addressing respectively hearing aid stigma, experienced pressure from others; perceived hearing aid benefit were evaluated with item response theory. The sample was comprised of 212 persons aged 55 years or more; 63 were hearing aid users, 64 with and 85 persons without hearing impairment according to guidelines for hearing aid reimbursement in the Netherlands. Bias was investigated relative to hearing aid use and hearing impairment within the differential test functioning framework. Items compromising model fit or demonstrating differential item functioning were dropped. The aid stigma scale was reduced from 6 to 4, the pressure scale from 7 to 4, and the aid unwanted scale from 5 to 4 items. This procedure resulted in bias-free scales ready for screening purposes and application to further understand the help-seeking process of the hearing impaired.

Hazardous metals in yellow items used in RCAs

International Nuclear Information System (INIS)

Brown, K.F.; Rankin, W.N.

1992-01-01

Yellow items used in Radiologically Controlled Areas (RCAs) that could contain hazardous metals were identified. X-ray fluorescence analyses indicated that thirty of the fifty-two items do contain hazardous metals. It is important to minimize the hazardous metals put into the wastes. The authors recommend that the specifications for all yellow items stocked in Stores be changed to specify that they contain no hazardous metals

Application of Item Response Theory to Tests of Substance-related Associative Memory

Science.gov (United States)

Shono, Yusuke; Grenard, Jerry L.; Ames, Susan L.; Stacy, Alan W.

2015-01-01

A substance-related word association test (WAT) is one of the commonly used indirect tests of substance-related implicit associative memory and has been shown to predict substance use. This study applied an item response theory (IRT) modeling approach to evaluate psychometric properties of the alcohol- and marijuana-related WATs and their items among 775 ethnically diverse at-risk adolescents. After examining the IRT assumptions, item fit, and differential item functioning (DIF) across gender and age groups, the original 18 WAT items were reduced to 14- and 15-items in the alcohol- and marijuana-related WAT, respectively. Thereafter, unidimensional one- and two-parameter logistic models (1PL and 2PL models) were fitted to the revised WAT items. The results demonstrated that both alcohol- and marijuana-related WATs have good psychometric properties. These results were discussed in light of the framework of a unified concept of construct validity (Messick, 1975, 1989, 1995). PMID:25134051

A novel method to identify hub pathways of rheumatoid arthritis based on differential pathway networks.

Science.gov (United States)

Wei, Shi-Tong; Sun, Yong-Hua; Zong, Shi-Hua

2017-09-01

The aim of the current study was to identify hub pathways of rheumatoid arthritis (RA) using a novel method based on differential pathway network (DPN) analysis. The present study proposed a DPN where protein‑protein interaction (PPI) network was integrated with pathway‑pathway interactions. Pathway data was obtained from background PPI network and the Reactome pathway database. Subsequently, pathway interactions were extracted from the pathway data by building randomized gene‑gene interactions and a weight value was assigned to each pathway interaction using Spearman correlation coefficient (SCC) to identify differential pathway interactions. Differential pathway interactions were visualized using Cytoscape to construct a DPN. Topological analysis was conducted to identify hub pathways that possessed the top 5% degree distribution of DPN. Modules of DPN were mined according to ClusterONE. A total of 855 pathways were selected to build pathway interactions. By filtrating pathway interactions of weight values >0.7, a DPN with 312 nodes and 791 edges was obtained. Topological degree analysis revealed 15 hub pathways, such as heparan sulfate/heparin‑glycosaminoglycan (HS‑GAG) degradation, HS‑GAG metabolism and keratan sulfate degradation for RA based on DPN. Furthermore, hub pathways were also important in modules, which validated the significance of hub pathways. In conclusion, the proposed method is a computationally efficient way to identify hub pathways of RA, which identified 15 hub pathways that may be potential biomarkers and provide insight to future investigation and treatment of RA.

Identification of metallic items that caused nickel dermatitis in Danish patients.

Science.gov (United States)

Thyssen, Jacob P; Menné, Torkil; Johansen, Jeanne D

2010-09-01

Nickel allergy is prevalent as assessed by epidemiological studies. In an attempt to further identify and characterize sources that may result in nickel allergy and dermatitis, we analysed items identified by nickel-allergic dermatitis patients as causative of nickel dermatitis by using the dimethylglyoxime (DMG) test. Dermatitis patients with nickel allergy of current relevance were identified over a 2-year period in a tertiary referral patch test centre. When possible, their work tools and personal items were examined with the DMG test. Among 95 nickel-allergic dermatitis patients, 70 (73.7%) had metallic items investigated for nickel release. A total of 151 items were investigated, and 66 (43.7%) gave positive DMG test reactions. Objects were nearly all purchased or acquired after the introduction of the EU Nickel Directive. Only one object had been inherited, and only two objects had been purchased outside of Denmark. DMG testing is valuable as a screening test for nickel release and should be used to identify relevant exposures in nickel-allergic patients. Mainly consumer items, but also work tools used in an occupational setting, released nickel in dermatitis patients. This study confirmed 'risk items' from previous studies, including mobile phones.

Social Concepts and Judgments: A Semantic Differential Analysis of the Concepts Feminist, Man, and Woman

Science.gov (United States)

Pierce, W. David; Sydie, R. A.; Stratkotter, Rainer

2003-01-01

Male and female participants (N = 274) made judgments about the social concepts of "feminist," "man," and "woman" on 63 semantic differential items. Factor analysis identified three basic dimensions termed evaluative, potency, and activity as well as two secondary factors called expressiveness and sexuality. Results for the evaluative dimension…

Development and psychometric evaluation of the PROMIS Pediatric Life Satisfaction item banks, child-report, and parent-proxy editions.

Science.gov (United States)

Forrest, Christopher B; Devine, Janine; Bevans, Katherine B; Becker, Brandon D; Carle, Adam C; Teneralli, Rachel E; Moon, JeanHee; Tucker, Carole A; Ravens-Sieberer, Ulrike

2018-01-01

To describe the psychometric evaluation and item response theory calibration of the PROMIS Pediatric Life Satisfaction item banks, child-report, and parent-proxy editions. A pool of 55 life satisfaction items was administered to 1992 children 8-17 years old and 964 parents of children 5-17 years old. Analyses included descriptive statistics, reliability, factor analysis, differential item functioning, and assessment of construct validity. Thirteen items were deleted because of poor psychometric performance. An 8-item short form was administered to a national sample of 996 children 8-17 years old, and 1294 parents of children 5-17 years old. The combined sample (2988 children and 2258 parents) was used in item response theory (IRT) calibration analyses. The final item banks were unidimensional, the items were locally independent, and the items were free from impactful differential item functioning. The 8-item and 4-item short form scales showed excellent reliability, convergent validity, and discriminant validity. Life satisfaction decreased with declining socio-economic status, presence of a special health care need, and increasing age for girls, but not boys. After IRT calibration, we found that 4- and 8-item short forms had a high degree of precision (reliability) across a wide range (>4 SD units) of the latent variable. The PROMIS Pediatric Life Satisfaction item banks and their short forms provide efficient, precise, and valid assessments of life satisfaction in children and youth.

The emotion dysregulation inventory: Psychometric properties and item response theory calibration in an autism spectrum disorder sample.

Science.gov (United States)

Mazefsky, Carla A; Yu, Lan; White, Susan W; Siegel, Matthew; Pilkonis, Paul A

2018-04-06

Individuals with autism spectrum disorder (ASD) often present with prominent emotion dysregulation that requires treatment but can be difficult to measure. The Emotion Dysregulation Inventory (EDI) was created using methods developed by the Patient-Reported Outcomes Measurement Information System (PROMIS ® ) to capture observable indicators of poor emotion regulation. Caregivers of 1,755 youth with ASD completed 66 candidate EDI items, and the final 30 items were selected based on classical test theory and item response theory (IRT) analyses. The analyses identified two factors: (a) Reactivity, characterized by intense, rapidly escalating, sustained, and poorly regulated negative emotional reactions, and (b) Dysphoria, characterized by anhedonia, sadness, and nervousness. The final items did not show differential item functioning (DIF) based on gender, age, intellectual ability, or verbal ability. Because the final items were calibrated using IRT, even a small number of items offers high precision, minimizing respondent burden. IRT co-calibration of the EDI with related measures demonstrated its superiority in assessing the severity of emotion dysregulation with as few as seven items. Validity of the EDI was supported by expert review, its association with related constructs (e.g., anxiety and depression symptoms, aggression), higher scores in psychiatric inpatients with ASD compared to a community ASD sample, and demonstration of test-retest stability and sensitivity to change. In sum, the EDI provides an efficient and sensitive method to measure emotion dysregulation for clinical assessment, monitoring, and research in youth with ASD of any level of cognitive or verbal ability. Autism Res 2018. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. This paper describes a new measure of poor emotional control called the Emotion Dysregulation Inventory (EDI). Caregivers of 1,755 youth with ASD completed candidate items, and advanced statistical

A comparison of discriminant logistic regression and Item Response Theory Likelihood-Ratio Tests for Differential Item Functioning (IRTLRDIF) in polytomous short tests.

Science.gov (United States)

Hidalgo, María D; López-Martínez, María D; Gómez-Benito, Juana; Guilera, Georgina

2016-01-01

Short scales are typically used in the social, behavioural and health sciences. This is relevant since test length can influence whether items showing DIF are correctly flagged. This paper compares the relative effectiveness of discriminant logistic regression (DLR) and IRTLRDIF for detecting DIF in polytomous short tests. A simulation study was designed. Test length, sample size, DIF amount and item response categories number were manipulated. Type I error and power were evaluated. IRTLRDIF and DLR yielded Type I error rates close to nominal level in no-DIF conditions. Under DIF conditions, Type I error rates were affected by test length DIF amount, degree of test contamination, sample size and number of item response categories. DLR showed a higher Type I error rate than did IRTLRDIF. Power rates were affected by DIF amount and sample size, but not by test length. DLR achieved higher power rates than did IRTLRDIF in very short tests, although the high Type I error rate involved means that this result cannot be taken into account. Test length had an important impact on the Type I error rate. IRTLRDIF and DLR showed a low power rate in short tests and with small sample sizes.

Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank.

Science.gov (United States)

Oude Voshaar, Martijn A H; Ten Klooster, Peter M; Vonkeman, Harald E; van de Laar, Mart A F J

2017-11-01

Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations. Seventy-two items generated from patient interviews and mapped to the International Classification of Functioning, Disability and Health (ICF) domestic life chapter were administered to 1128 adults representative of the Dutch population. The partial credit model was fitted to the item responses and evaluated with respect to its assumptions, model fit, and differential item functioning (DIF). Measurement performance of a computerized adaptive testing (CAT) algorithm was compared with the SF-36 physical functioning scale (PF-10). A final bank of 41 items was developed. All items demonstrated acceptable fit to the partial credit model and measurement invariance across age, sex, and educational level. Five- and ten-item CAT simulations were shown to have high measurement precision, which exceeded that of SF-36 physical functioning scale across the physical function continuum. Floor effects were absent for a 10-item empirical CAT simulation, and ceiling effects were low (13.5%) compared with SF-36 physical functioning (38.1%). CAT also discriminated better than SF-36 physical functioning between age groups, number of chronic conditions, and respondents with or without rheumatic conditions. The Rasch assessment of everyday activity limitations (REAL) item bank will hopefully prove a useful instrument for assessing everyday activity limitations. T-scores obtained using derived measures can be used to benchmark physical function outcomes against the general Dutch adult population.

Harmonizing Measures of Cognitive Performance Across International Surveys of Aging Using Item Response Theory.

Science.gov (United States)

Chan, Kitty S; Gross, Alden L; Pezzin, Liliana E; Brandt, Jason; Kasper, Judith D

2015-12-01

To harmonize measures of cognitive performance using item response theory (IRT) across two international aging studies. Data for persons ≥65 years from the Health and Retirement Study (HRS, N = 9,471) and the English Longitudinal Study of Aging (ELSA, N = 5,444). Cognitive performance measures varied (HRS fielded 25, ELSA 13); 9 were in common. Measurement precision was examined for IRT scores based on (a) common items, (b) common items adjusted for differential item functioning (DIF), and (c) DIF-adjusted all items. Three common items (day of date, immediate word recall, and delayed word recall) demonstrated DIF by survey. Adding survey-specific items improved precision but mainly for HRS respondents at lower cognitive levels. IRT offers a feasible strategy for harmonizing cognitive performance measures across other surveys and for other multi-item constructs of interest in studies of aging. Practical implications depend on sample distribution and the difficulty mix of in-common and survey-specific items. © The Author(s) 2015.

Item response analysis on an examination in anesthesiology for medical students in Taiwan: A comparison of one- and two-parameter logistic models

Directory of Open Access Journals (Sweden)

Yu-Feng Huang

2013-06-01

Conclusion: Item response models are useful for medical test analyses and provide valuable information about model comparisons and identification of differential items other than test reliability, item difficulty, and examinee's ability.

High-content phenotypic screening and triaging strategy to identify small molecules driving oligodendrocyte progenitor cell differentiation.

Science.gov (United States)

Peppard, Jane V; Rugg, Catherine A; Smicker, Matthew A; Powers, Elaine; Harnish, Erica; Prisco, Joy; Cirovic, Dragan; Wright, Paul S; August, Paul R; Chandross, Karen J

2015-03-01

Multiple Sclerosis is a demyelinating disease of the CNS and the primary cause of neurological disability in young adults. Loss of myelinating oligodendrocytes leads to neuronal dysfunction and death and is an important contributing factor to this disease. Endogenous oligodendrocyte precursor cells (OPCs), which on differentiation are responsible for replacing myelin, are present in the adult CNS. As such, therapeutic agents that can stimulate OPCs to differentiate and remyelinate demyelinated axons under pathologic conditions may improve neuronal function and clinical outcome. We describe the details of an automated, cell-based, morphometric-based, high-content screen that is used to identify small molecules eliciting the differentiation of OPCs after 3 days. Primary screening was performed using rat CG-4 cells maintained in culture conditions that normally support a progenitor cell-like state. From a library of 73,000 diverse small molecules within the Sanofi collection, 342 compounds were identified that increased OPC morphological complexity as an indicator of oligodendrocyte maturation. Subsequent to the primary high-content screen, a suite of cellular assays was established that identified 22 nontoxic compounds that selectively stimulated primary rat OPCs but not C2C12 muscle cell differentiation. This rigorous triaging yielded several chemical series for further expansion and bio- or cheminformatics studies, and their compelling biological activity merits further investigation. © 2014 Society for Laboratory Automation and Screening.

Yeast three-hybrid screen identifies TgBRADIN/GRA24 as a negative regulator of Toxoplasma gondii bradyzoite differentiation.

Directory of Open Access Journals (Sweden)

Anahi V Odell

Full Text Available Differentiation of the protozoan parasite Toxoplasma gondii into its latent bradyzoite stage is a key event in the parasite's life cycle. Compound 2 is an imidazopyridine that was previously shown to inhibit the parasite lytic cycle, in part through inhibition of parasite cGMP-dependent protein kinase. We show here that Compound 2 can also enhance parasite differentiation, and we use yeast three-hybrid analysis to identify TgBRADIN/GRA24 as a parasite protein that interacts directly or indirectly with the compound. Disruption of the TgBRADIN/GRA24 gene leads to enhanced differentiation of the parasite, and the TgBRADIN/GRA24 knockout parasites show decreased susceptibility to the differentiation-enhancing effects of Compound 2. This study represents the first use of yeast three-hybrid analysis to study small-molecule mechanism of action in any pathogenic microorganism, and it identifies a previously unrecognized inhibitor of differentiation in T. gondii. A better understanding of the proteins and mechanisms regulating T. gondii differentiation will enable new approaches to preventing the establishment of chronic infection in this important human pathogen.

Not saying I am happy does not mean I am not: cultural influences on responses to positive affect items in the CES-D.

Science.gov (United States)

Jang, Yuri; Kwag, Kyung Hwa; Chiriboga, David A

2010-11-01

Given the emphasis on modesty and self-effacement in Asian societies, the present study explored differential item responses for 2 positive affect items (5 = Hopeful and 8 = Happy) on a short form of the Center for Epidemiologic Studies-Depression scale. The samples consisted of elderly non-Hispanic Whites (n = 450), Korean Americans (n = 519), and Koreans (n = 2,030). Multiple Indicator Multiple Cause models were estimated to identify the impact of group membership on responses to the positive affect items while controlling for the latent trait of depressive symptoms. The data revealed that Koreans and Korean Americans were less likely than non-Hispanic Whites to endorse the positive affect items. Compared with Korean Americans who were more acculturated to mainstream American culture, those who were less acculturated were less likely to endorse the positive affect items. Our findings support the notion that the way in which people endorse depressive symptoms is substantially influenced by cultural orientation. These findings call into question the common use of simple mean comparisons and a universal cutoff point across diverse cultural groups.

Fourier transform infrared microspectroscopy identifies early lineage commitment in differentiating human embryonic stem cells.

Science.gov (United States)

Heraud, Philip; Ng, Elizabeth S; Caine, Sally; Yu, Qing C; Hirst, Claire; Mayberry, Robyn; Bruce, Amanda; Wood, Bayden R; McNaughton, Don; Stanley, Edouard G; Elefanty, Andrew G

2010-03-01

Human ESCs (hESCs) are a valuable tool for the study of early human development and represent a source of normal differentiated cells for pharmaceutical and biotechnology applications and ultimately for cell replacement therapies. For all applications, it will be necessary to develop assays to validate the efficacy of hESC differentiation. We explored the capacity for FTIR spectroscopy, a technique that rapidly characterises cellular macromolecular composition, to discriminate mesendoderm or ectoderm committed cells from undifferentiated hESCs. Distinct infrared spectroscopic "signatures" readily distinguished hESCs from these early differentiated progeny, with bioinformatic models able to correctly classify over 97% of spectra. These data identify a role for FTIR spectroscopy as a new modality to complement conventional analyses of hESCs and their derivatives. FTIR spectroscopy has the potential to provide low-cost, automatable measurements for the quality control of stem and differentiated cells to be used in industry and regenerative medicine. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

Identifying Promising Items: The Use of Crowdsourcing in the Development of Assessment Instruments

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Sadler, Philip M.; Sonnert, Gerhard; Coyle, Harold P.; Miller, Kelly A.

2016-01-01

The psychometrically sound development of assessment instruments requires pilot testing of candidate items as a first step in gauging their quality, typically a time-consuming and costly effort. Crowdsourcing offers the opportunity for gathering data much more quickly and inexpensively than from most targeted populations. In a simulation of a…

DISC Predictive Scales (DPS): Factor Structure and Uniform Differential Item Functioning Across Gender and Three Racial/Ethnic Groups for ADHD, Conduct Disorder, and Oppositional Defiant Disorder Symptoms

OpenAIRE

Wiesner, Margit; Kanouse, David E.; Elliott, Marc N.; Windle, Michael; Schuster, Mark A.

2015-01-01

The factor structure and potential uniform differential item functioning (DIF) among gender and three racial/ethnic groups of adolescents (African American, Latino, White) were evaluated for attention deficit/hyperactivity disorder (ADHD), conduct disorder (CD), and oppositional defiant disorder (ODD) symptom scores of the DISC Predictive Scales (DPS; Leung et al., 2005; Lucas et al., 2001). Primary caregivers reported on DSM–IV ADHD, CD, and ODD symptoms for a probability sample of 4,491 chi...

The Long-Term Conditions Questionnaire: conceptual framework and item development.

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Peters, Michele; Potter, Caroline M; Kelly, Laura; Hunter, Cheryl; Gibbons, Elizabeth; Jenkinson, Crispin; Coulter, Angela; Forder, Julien; Towers, Ann-Marie; A'Court, Christine; Fitzpatrick, Ray

2016-01-01

To identify the main issues of importance when living with long-term conditions to refine a conceptual framework for informing the item development of a patient-reported outcome measure for long-term conditions. Semi-structured qualitative interviews (n=48) were conducted with people living with at least one long-term condition. Participants were recruited through primary care. The interviews were transcribed verbatim and analyzed by thematic analysis. The analysis served to refine the conceptual framework, based on reviews of the literature and stakeholder consultations, for developing candidate items for a new measure for long-term conditions. Three main organizing concepts were identified: impact of long-term conditions, experience of services and support, and self-care. The findings helped to refine a conceptual framework, leading to the development of 23 items that represent issues of importance in long-term conditions. The 23 candidate items formed the first draft of the measure, currently named the Long-Term Conditions Questionnaire. The aim of this study was to refine the conceptual framework and develop items for a patient-reported outcome measure for long-term conditions, including single and multiple morbidities and physical and mental health conditions. Qualitative interviews identified the key themes for assessing outcomes in long-term conditions, and these underpinned the development of the initial draft of the measure. These initial items will undergo cognitive testing to refine the items prior to further validation in a survey.

A comparison of Rasch item-fit and Cronbach's alpha item reduction analysis for the development of a Quality of Life scale for children and adolescents.

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Erhart, M; Hagquist, C; Auquier, P; Rajmil, L; Power, M; Ravens-Sieberer, U

2010-07-01

This study compares item reduction analysis based on classical test theory (maximizing Cronbach's alpha - approach A), with analysis based on the Rasch Partial Credit Model item-fit (approach B), as applied to children and adolescents' health-related quality of life (HRQoL) items. The reliability and structural, cross-cultural and known-group validity of the measures were examined. Within the European KIDSCREEN project, 3019 children and adolescents (8-18 years) from seven European countries answered 19 HRQoL items of the Physical Well-being dimension of a preliminary KIDSCREEN instrument. The Cronbach's alpha and corrected item total correlation (approach A) were compared with infit mean squares and the Q-index item-fit derived according to a partial credit model (approach B). Cross-cultural differential item functioning (DIF ordinal logistic regression approach), structural validity (confirmatory factor analysis and residual correlation) and relative validity (RV) for socio-demographic and health-related factors were calculated for approaches (A) and (B). Approach (A) led to the retention of 13 items, compared with 11 items with approach (B). The item overlap was 69% for (A) and 78% for (B). The correlation coefficient of the summated ratings was 0.93. The Cronbach's alpha was similar for both versions [0.86 (A); 0.85 (B)]. Both approaches selected some items that are not strictly unidimensional and items displaying DIF. RV ratios favoured (A) with regard to socio-demographic aspects. Approach (B) was superior in RV with regard to health-related aspects. Both types of item reduction analysis should be accompanied by additional analyses. Neither of the two approaches was universally superior with regard to cultural, structural and known-group validity. However, the results support the usability of the Rasch method for developing new HRQoL measures for children and adolescents.

The Role of Item Models in Automatic Item Generation

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Gierl, Mark J.; Lai, Hollis

2012-01-01

Automatic item generation represents a relatively new but rapidly evolving research area where cognitive and psychometric theories are used to produce tests that include items generated using computer technology. Automatic item generation requires two steps. First, test development specialists create item models, which are comparable to templates…

Assessing item fit for unidimensional item response theory models using residuals from estimated item response functions.

Science.gov (United States)

Haberman, Shelby J; Sinharay, Sandip; Chon, Kyong Hee

2013-07-01

Residual analysis (e.g. Hambleton & Swaminathan, Item response theory: principles and applications, Kluwer Academic, Boston, 1985; Hambleton, Swaminathan, & Rogers, Fundamentals of item response theory, Sage, Newbury Park, 1991) is a popular method to assess fit of item response theory (IRT) models. We suggest a form of residual analysis that may be applied to assess item fit for unidimensional IRT models. The residual analysis consists of a comparison of the maximum-likelihood estimate of the item characteristic curve with an alternative ratio estimate of the item characteristic curve. The large sample distribution of the residual is proved to be standardized normal when the IRT model fits the data. We compare the performance of our suggested residual to the standardized residual of Hambleton et al. (Fundamentals of item response theory, Sage, Newbury Park, 1991) in a detailed simulation study. We then calculate our suggested residuals using data from an operational test. The residuals appear to be useful in assessing the item fit for unidimensional IRT models.

Problems with the factor analysis of items: Solutions based on item response theory and item parcelling

Directory of Open Access Journals (Sweden)

Gideon P. De Bruin

2004-10-01

Full Text Available The factor analysis of items often produces spurious results in the sense that unidimensional scales appear multidimensional. This may be ascribed to failure in meeting the assumptions of linearity and normality on which factor analysis is based. Item response theory is explicitly designed for the modelling of the non-linear relations between ordinal variables and provides a strong alternative to the factor analysis of items. Items may also be combined in parcels that are more likely to satisfy the assumptions of factor analysis than do the items. The use of the Rasch rating scale model and the factor analysis of parcels is illustrated with data obtained with the Locus of Control Inventory. The results of these analyses are compared with the results obtained through the factor analysis of items. It is shown that the Rasch rating scale model and the factoring of parcels produce superior results to the factor analysis of items. Recommendations for the analysis of scales are made. Opsomming Die faktorontleding van items lewer dikwels misleidende resultate op, veral in die opsig dat eendimensionele skale as meerdimensioneel voorkom. Hierdie resultate kan dikwels daaraan toegeskryf word dat daar nie aan die aannames van lineariteit en normaliteit waarop faktorontleding berus, voldoen word nie. Itemresponsteorie, wat eksplisiet vir die modellering van die nie-liniêre verbande tussen ordinale items ontwerp is, bied ’n aantreklike alternatief vir die faktorontleding van items. Items kan ook in pakkies gegroepeer word wat meer waarskynlik aan die aannames van faktorontleding voldoen as individuele items. Die gebruik van die Rasch beoordelingskaalmodel en die faktorontleding van pakkies word aan die hand van data wat met die Lokus van Beheervraelys verkry is, gedemonstreer. Die resultate van hierdie ontledings word vergelyk met die resultate wat deur ‘n faktorontleding van die individuele items verkry is. Die resultate dui daarop dat die Rasch

DISC Predictive Scales (DPS): Factor structure and uniform differential item functioning across gender and three racial/ethnic groups for ADHD, conduct disorder, and oppositional defiant disorder symptoms.

Science.gov (United States)

Wiesner, Margit; Windle, Michael; Kanouse, David E; Elliott, Marc N; Schuster, Mark A

2015-12-01

The factor structure and potential uniform differential item functioning (DIF) among gender and three racial/ethnic groups of adolescents (African American, Latino, White) were evaluated for attention deficit/hyperactivity disorder (ADHD), conduct disorder (CD), and oppositional defiant disorder (ODD) symptom scores of the DISC Predictive Scales (DPS; Leung et al., 2005; Lucas et al., 2001). Primary caregivers reported on DSM-IV ADHD, CD, and ODD symptoms for a probability sample of 4,491 children from three geographical regions who took part in the Healthy Passages study (mean age = 12.60 years, SD = 0.66). Confirmatory factor analysis indicated that the expected 3-factor structure was tenable for the data. Multiple indicators multiple causes (MIMIC) modeling revealed uniform DIF for three ADHD and 9 ODD item scores, but not for any of the CD item scores. Uniform DIF was observed predominantly as a function of child race/ethnicity, but minimally as a function of child gender. On the positive side, uniform DIF had little impact on latent mean differences of ADHD, CD, and ODD symptomatology among gender and racial/ethnic groups. Implications of the findings for researchers and practitioners are discussed. (c) 2015 APA, all rights reserved).

Numerical Differentiation Methods for Computing Error Covariance Matrices in Item Response Theory Modeling: An Evaluation and a New Proposal

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Tian, Wei; Cai, Li; Thissen, David; Xin, Tao

2013-01-01

In item response theory (IRT) modeling, the item parameter error covariance matrix plays a critical role in statistical inference procedures. When item parameters are estimated using the EM algorithm, the parameter error covariance matrix is not an automatic by-product of item calibration. Cai proposed the use of Supplemented EM algorithm for…

Differential geometry and mathematical physics

CERN Document Server

Rudolph, Gerd

Starting from an undergraduate level, this book systematically develops the basics of • Calculus on manifolds, vector bundles, vector fields and differential forms, • Lie groups and Lie group actions, • Linear symplectic algebra and symplectic geometry, • Hamiltonian systems, symmetries and reduction, integrable systems and Hamilton-Jacobi theory. The topics listed under the first item are relevant for virtually all areas of mathematical physics. The second and third items constitute the link between abstract calculus and the theory of Hamiltonian systems. The last item provides an introduction to various aspects of this theory, including Morse families, the Maslov class and caustics. The book guides the reader from elementary differential geometry to advanced topics in the theory of Hamiltonian systems with the aim of making current research literature accessible. The style is that of a mathematical textbook,with full proofs given in the text or as exercises. The material is illustrated by numerous d...

Disparities in Sense of Community: True Race Differences or Differential Item Functioning?

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Coffman, Donna L.; BeLue, Rhonda

2009-01-01

The sense of community index (SCI) has been widely used to measure psychological sense of community (SOC). Furthermore, SOC has been found to differ among racial groups. Because different ethnic groups have different cultural and historical experiences that may lead to different interpretations of measurement items, it is important to know whether…

Item information and discrimination functions for trinary PCM items

NARCIS (Netherlands)

Akkermans, Wies; Muraki, Eiji

1997-01-01

For trinary partial credit items the shape of the item information and the item discrimination function is examined in relation to the item parameters. In particular, it is shown that these functions are unimodal if δ2 – δ1 < 4 ln 2 and bimodal otherwise. The locations and values of the maxima are

Lost and misplaced items and assistive devices in nursing homes: Identifying problems and technological opportunities through participatory design research.

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Oude Weernink, C E; Sweegers, L; Relou, L; van der Zijpp, T J; van Hoof, J

2018-02-06

Modern healthcare, including nursing home care, goes together with the use of technologies to support treatment, the provision of care and daily activities. The challenges concerning the implementation of such technologies are numerous. One of these emerging technologies are location technologies (RTLS or Real-Time Location Systems). that can be utilized in the nursing home for monitoring the use and location of assets. This paper describes a participatory design study of RTLS based on context mapping, conducted in two nursing home organizations. Rather than investigating the technological possibilities, this study investigates the needs and wishes from the perspective of the care professional. The study identified semantic themes that relate to the practicalities of lost and misplaced items in the nursing home, as well as latent themes that cover the wishes regarding technology in the nursing homes. The organizational culture and building typology may play a role in losing items. The participants in this study indicated that RTLS can provide a solution to some of the challenges that they encounter in the workplace. However, the implementation of new technologies should be done with care and should be integrated into existing ICT systems in order to minimize additional training and posing a burden on the workload.

f-divergence cutoff index to simultaneously identify differential expression in the integrated transcriptome and proteome

OpenAIRE

Tang, Shaojun; Hemberg, Martin; Cansizoglu, Ertugrul; Belin, Stephane; Kosik, Kenneth; Kreiman, Gabriel; Steen, Hanno; Steen, Judith

2016-01-01

The ability to integrate 'omics' (i.e., transcriptomics and proteomics) is becoming increasingly important to the understanding of regulatory mechanisms. There are currently no tools available to identify differentially expressed genes (DEGs)across different 'omics'data types or multi-dimensional data including time courses. We present a model capable of simultaneously identifying DEGs from continuous and discrete transcriptomic, proteomic and integrated proteogenomic data. We show that...

Item level diagnostics and model - data fit in item response theory ...

African Journals Online (AJOL)

Item response theory (IRT) is a framework for modeling and analyzing item response data. Item-level modeling gives IRT advantages over classical test theory. The fit of an item score pattern to an item response theory (IRT) models is a necessary condition that must be assessed for further use of item and models that best fit ...

Evaluating HIV Knowledge Questionnaires Among Men Who Have Sex with Men: A Multi-Study Item Response Theory Analysis.

Science.gov (United States)

Janulis, Patrick; Newcomb, Michael E; Sullivan, Patrick; Mustanski, Brian

2018-01-01

Knowledge about the transmission, prevention, and treatment of HIV remains a critical element in psychosocial models of HIV risk behavior and is commonly used as an outcome in HIV prevention interventions. However, most HIV knowledge questions have not undergone rigorous psychometric testing such as using item response theory. The current study used data from six studies of men who have sex with men (MSM; n = 3565) to (1) examine the item properties of HIV knowledge questions, (2) test for differential item functioning on commonly studied characteristics (i.e., age, race/ethnicity, and HIV risk behavior), (3) select items with the optimal item characteristics, and (4) leverage this combined dataset to examine the potential moderating effect of age on the relationship between condomless anal sex (CAS) and HIV knowledge. Findings indicated that existing questions tend to poorly differentiate those with higher levels of HIV knowledge, but items were relatively robust across diverse individuals. Furthermore, age moderated the relationship between CAS and HIV knowledge with older MSM having the strongest association. These findings suggest that additional items are required in order to capture a more nuanced understanding of HIV knowledge and that the association between CAS and HIV knowledge may vary by age.

Bayes Factor Covariance Testing in Item Response Models.

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Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip

2017-12-01

Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning the underlying covariance structure are evaluated using (fractional) Bayes factor tests. The support for a unidimensional factor (i.e., assumption of local independence) and differential item functioning are evaluated by testing the covariance components. The posterior distribution of common covariance components is obtained in closed form by transforming latent responses with an orthogonal (Helmert) matrix. This posterior distribution is defined as a shifted-inverse-gamma, thereby introducing a default prior and a balanced prior distribution. Based on that, an MCMC algorithm is described to estimate all model parameters and to compute (fractional) Bayes factor tests. Simulation studies are used to show that the (fractional) Bayes factor tests have good properties for testing the underlying covariance structure of binary response data. The method is illustrated with two real data studies.

Using Explanatory Item Response Models to Evaluate Complex Scientific Tasks Designed for the Next Generation Science Standards

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Chiu, Tina

This dissertation includes three studies that analyze a new set of assessment tasks developed by the Learning Progressions in Middle School Science (LPS) Project. These assessment tasks were designed to measure science content knowledge on the structure of matter domain and scientific argumentation, while following the goals from the Next Generation Science Standards (NGSS). The three studies focus on the evidence available for the success of this design and its implementation, generally labelled as "validity" evidence. I use explanatory item response models (EIRMs) as the overarching framework to investigate these assessment tasks. These models can be useful when gathering validity evidence for assessments as they can help explain student learning and group differences. In the first study, I explore the dimensionality of the LPS assessment by comparing the fit of unidimensional, between-item multidimensional, and Rasch testlet models to see which is most appropriate for this data. By applying multidimensional item response models, multiple relationships can be investigated, and in turn, allow for a more substantive look into the assessment tasks. The second study focuses on person predictors through latent regression and differential item functioning (DIF) models. Latent regression models show the influence of certain person characteristics on item responses, while DIF models test whether one group is differentially affected by specific assessment items, after conditioning on latent ability. Finally, the last study applies the linear logistic test model (LLTM) to investigate whether item features can help explain differences in item difficulties.

Linking Existing Instruments to Develop an Activity of Daily Living Item Bank.

Science.gov (United States)

Li, Chih-Ying; Romero, Sergio; Bonilha, Heather S; Simpson, Kit N; Simpson, Annie N; Hong, Ickpyo; Velozo, Craig A

2018-03-01

This study examined dimensionality and item-level psychometric properties of an item bank measuring activities of daily living (ADL) across inpatient rehabilitation facilities and community living centers. Common person equating method was used in the retrospective veterans data set. This study examined dimensionality, model fit, local independence, and monotonicity using factor analyses and fit statistics, principal component analysis (PCA), and differential item functioning (DIF) using Rasch analysis. Following the elimination of invalid data, 371 veterans who completed both the Functional Independence Measure (FIM) and minimum data set (MDS) within 6 days were retained. The FIM-MDS item bank demonstrated good internal consistency (Cronbach's α = .98) and met three rating scale diagnostic criteria and three of the four model fit statistics (comparative fit index/Tucker-Lewis index = 0.98, root mean square error of approximation = 0.14, and standardized root mean residual = 0.07). PCA of Rasch residuals showed the item bank explained 94.2% variance. The item bank covered the range of θ from -1.50 to 1.26 (item), -3.57 to 4.21 (person) with person strata of 6.3. The findings indicated the ADL physical function item bank constructed from FIM and MDS measured a single latent trait with overall acceptable item-level psychometric properties, suggesting that it is an appropriate source for developing efficient test forms such as short forms and computerized adaptive tests.

Concreteness effects in short-term memory: a test of the item-order hypothesis.

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Roche, Jaclynn; Tolan, G Anne; Tehan, Gerald

2011-12-01

The following experiments explore word length and concreteness effects in short-term memory within an item-order processing framework. This framework asserts order memory is better for those items that are relatively easy to process at the item level. However, words that are difficult to process benefit at the item level for increased attention/resources being applied. The prediction of the model is that differential item and order processing can be detected in episodic tasks that differ in the degree to which item or order memory are required by the task. The item-order account has been applied to the word length effect such that there is a short word advantage in serial recall but a long word advantage in item recognition. The current experiment considered the possibility that concreteness effects might be explained within the same framework. In two experiments, word length (Experiment 1) and concreteness (Experiment 2) are examined using forward serial recall, backward serial recall, and item recognition. These results for word length replicate previous studies showing the dissociation in item and order tasks. The same was not true for the concreteness effect. In all three tasks concrete words were better remembered than abstract words. The concreteness effect cannot be explained in terms of an item-order trade off. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Murdock free recall data: The initial recall search identifies the context by the location of the least remembered item and produces only better remembered items in proportion to the total recall difference.

OpenAIRE

Tarnow, Dr. Eugen

2009-01-01

The curious free recall data of Murdock (1962) shows an additional surprise that seems to have gone undetected until now: the probability of guessing an item in the initial recall is not identical to the overall free recall curve. Initial recall of an item is well correlated with the total recall of that item using a straight line but with an unexpected offset. The offset varies with the presentation rate and the total number of list items but in each case it is the same as the total recall ...

Counterfeit and Fraudulent Items - Mitigating the risk

International Nuclear Information System (INIS)

Tannenbaum, Marc

2011-01-01

This presentation (slides) provides an overview of the industry's challenges and activities. Firstly, it outlines the differences between counterfeit, fraudulent, suspect, and also substandard items. Notice is given that items could be found not to meet the standard, but the difference in the intent to deceive with counterfeit and fraudulent items is the critical element. Examples from other industries are used which also rely heavily on the assurance of quality for safety. It also informs that EPRI has just completed a report in October 2009 in coordination with other US government agencies and industry organizations; this report, entitled Counterfeit, Substandard and Fraudulent Items, number 1019163, is available for free on the EPRI web site. As a follow-up to this report, EPRI is developing a CFSI Database; any country interested in a collaborative agreement is invited to use and contribute to the database information. Finally, it stresses the importance of the oversight of contractors, training to raise the awareness of the employees and the inspectors, and having a response plan for identified items

Better assessment of physical function: item improvement is neglected but essential.

Science.gov (United States)

Bruce, Bonnie; Fries, James F; Ambrosini, Debbie; Lingala, Bharathi; Gandek, Barbara; Rose, Matthias; Ware, John E

2009-01-01

Physical function is a key component of patient-reported outcome (PRO) assessment in rheumatology. Modern psychometric methods, such as Item Response Theory (IRT) and Computerized Adaptive Testing, can materially improve measurement precision at the item level. We present the qualitative and quantitative item-evaluation process for developing the Patient Reported Outcomes Measurement Information System (PROMIS) Physical Function item bank. The process was stepwise: we searched extensively to identify extant Physical Function items and then classified and selectively reduced the item pool. We evaluated retained items for content, clarity, relevance and comprehension, reading level, and translation ease by experts and patient surveys, focus groups, and cognitive interviews. We then assessed items by using classic test theory and IRT, used confirmatory factor analyses to estimate item parameters, and graded response modeling for parameter estimation. We retained the 20 Legacy (original) Health Assessment Questionnaire Disability Index (HAQ-DI) and the 10 SF-36's PF-10 items for comparison. Subjects were from rheumatoid arthritis, osteoarthritis, and healthy aging cohorts (n = 1,100) and a national Internet sample of 21,133 subjects. We identified 1,860 items. After qualitative and quantitative evaluation, 124 newly developed PROMIS items composed the PROMIS item bank, which included revised Legacy items with good fit that met IRT model assumptions. Results showed that the clearest and best-understood items were simple, in the present tense, and straightforward. Basic tasks (like dressing) were more relevant and important versus complex ones (like dancing). Revised HAQ-DI and PF-10 items with five response options had higher item-information content than did comparable original Legacy items with fewer response options. IRT analyses showed that the Physical Function domain satisfied general criteria for unidimensionality with one-, two-, three-, and four-factor models

Memory for Items and Relationships among Items Embedded in Realistic Scenes: Disproportionate Relational Memory Impairments in Amnesia

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Hannula, Deborah E.; Tranel, Daniel; Allen, John S.; Kirchhoff, Brenda A.; Nickel, Allison E.; Cohen, Neal J.

2014-01-01

Objective The objective of this study was to examine the dependence of item memory and relational memory on medial temporal lobe (MTL) structures. Patients with amnesia, who either had extensive MTL damage or damage that was relatively restricted to the hippocampus, were tested, as was a matched comparison group. Disproportionate relational memory impairments were predicted for both patient groups, and those with extensive MTL damage were also expected to have impaired item memory. Method Participants studied scenes, and were tested with interleaved two-alternative forced-choice probe trials. Probe trials were either presented immediately after the corresponding study trial (lag 1), five trials later (lag 5), or nine trials later (lag 9) and consisted of the studied scene along with a manipulated version of that scene in which one item was replaced with a different exemplar (item memory test) or was moved to a new location (relational memory test). Participants were to identify the exact match of the studied scene. Results As predicted, patients were disproportionately impaired on the test of relational memory. Item memory performance was marginally poorer among patients with extensive MTL damage, but both groups were impaired relative to matched comparison participants. Impaired performance was evident at all lags, including the shortest possible lag (lag 1). Conclusions The results are consistent with the proposed role of the hippocampus in relational memory binding and representation, even at short delays, and suggest that the hippocampus may also contribute to successful item memory when items are embedded in complex scenes. PMID:25068665

Three controversies over item disclosure in medical licensure examinations

Directory of Open Access Journals (Sweden)

Yoon Soo Park

2015-09-01

Full Text Available In response to views on public's right to know, there is growing attention to item disclosure – release of items, answer keys, and performance data to the public – in medical licensure examinations and their potential impact on the test's ability to measure competence and select qualified candidates. Recent debates on this issue have sparked legislative action internationally, including South Korea, with prior discussions among North American countries dating over three decades. The purpose of this study is to identify and analyze three issues associated with item disclosure in medical licensure examinations – 1 fairness and validity, 2 impact on passing levels, and 3 utility of item disclosure – by synthesizing existing literature in relation to standards in testing. Historically, the controversy over item disclosure has centered on fairness and validity. Proponents of item disclosure stress test takers’ right to know, while opponents argue from a validity perspective. Item disclosure may bias item characteristics, such as difficulty and discrimination, and has consequences on setting passing levels. To date, there has been limited research on the utility of item disclosure for large scale testing. These issues requires ongoing and careful consideration.

Reading ability and print exposure: item response theory analysis of the author recognition test.

Science.gov (United States)

Moore, Mariah; Gordon, Peter C

2015-12-01

In the author recognition test (ART), participants are presented with a series of names and foils and are asked to indicate which ones they recognize as authors. The test is a strong predictor of reading skill, and this predictive ability is generally explained as occurring because author knowledge is likely acquired through reading or other forms of print exposure. In this large-scale study (1,012 college student participants), we used item response theory (IRT) to analyze item (author) characteristics in order to facilitate identification of the determinants of item difficulty, provide a basis for further test development, and optimize scoring of the ART. Factor analysis suggested a potential two-factor structure of the ART, differentiating between literary and popular authors. Effective and ineffective author names were identified so as to facilitate future revisions of the ART. Analyses showed that the ART is a highly significant predictor of the time spent encoding words, as measured using eyetracking during reading. The relationship between the ART and time spent reading provided a basis for implementing a higher penalty for selecting foils, rather than the standard method of ART scoring (names selected minus foils selected). The findings provide novel support for the view that the ART is a valid indicator of reading volume. Furthermore, they show that frequency data can be used to select items of appropriate difficulty, and that frequency data from corpora based on particular time periods and types of texts may allow adaptations of the test for different populations.

Epigenetic Library Screen Identifies Abexinostat as Novel Regulator of Adipocytic and Osteoblastic Differentiation of Human Skeletal (Mesenchymal) Stem Cells

Science.gov (United States)

Ali, Dalia; Hamam, Rimi; Alfayez, Musaed; Kassem, Moustapha; Aldahmash, Abdullah

2016-01-01

The epigenetic mechanisms promoting lineage-specific commitment of human skeletal (mesenchymal or stromal) stem cells (hMSCs) into adipocytes or osteoblasts are still not fully understood. Herein, we performed an epigenetic library functional screen and identified several novel compounds, including abexinostat, which promoted adipocytic and osteoblastic differentiation of hMSCs. Using gene expression microarrays, chromatin immunoprecipitation for H3K9Ac combined with high-throughput DNA sequencing (ChIP-seq), and bioinformatics, we identified several key genes involved in regulating stem cell proliferation and differentiation that were targeted by abexinostat. Concordantly, ChIP-quantitative polymerase chain reaction revealed marked increase in H3K9Ac epigenetic mark on the promoter region of AdipoQ, FABP4, PPARγ, KLF15, CEBPA, SP7, and ALPL in abexinostat-treated hMSCs. Pharmacological inhibition of focal adhesion kinase (PF-573228) or insulin-like growth factor-1R/insulin receptor (NVP-AEW51) signaling exhibited significant inhibition of abexinostat-mediated adipocytic differentiation, whereas inhibition of WNT (XAV939) or transforming growth factor-β (SB505124) signaling abrogated abexinostat-mediated osteogenic differentiation of hMSCs. Our findings provide insight into the understanding of the relationship between the epigenetic effect of histone deacetylase inhibitors, transcription factors, and differentiation pathways governing adipocyte and osteoblast differentiation. Manipulating such pathways allows a novel use for epigenetic compounds in hMSC-based therapies and tissue engineering. Significance This unbiased epigenetic library functional screen identified several novel compounds, including abexinostat, that promoted adipocytic and osteoblastic differentiation of human skeletal (mesenchymal or stromal) stem cells (hMSCs). These data provide new insight into the understanding of the relationship between the epigenetic effect of histone deacetylase

Beneficial effects of semantic memory support on older adults' episodic memory: Differential patterns of support of item and associative information.

Science.gov (United States)

Mohanty, Praggyan Pam; Naveh-Benjamin, Moshe; Ratneshwar, Srinivasan

2016-02-01

The effects of two types of semantic memory support-meaningfulness of an item and relatedness between items-in mitigating age-related deficits in item and associative, memory are examined in a marketing context. In Experiment 1, participants studied less (vs. more) meaningful brand logo graphics (pictures) paired with meaningful brand names (words) and later were assessed by item (old/new) and associative (intact/recombined) memory recognition tests. Results showed that meaningfulness of items eliminated age deficits in item memory, while equivalently boosting associative memory for older and younger adults. Experiment 2, in which related and unrelated brand logo graphics and brand name pairs served as stimuli, revealed that relatedness between items eliminated age deficits in associative memory, while improving to the same degree item memory in older and younger adults. Experiment 2 also provided evidence for a probable boundary condition that could reconcile seemingly contradictory extant results. Overall, these experiments provided evidence that although the two types of semantic memory support can improve both item and associative memory in older and younger adults, older adults' memory deficits can be eliminated when the type of support provided is compatible with the type of information required to perform well on the test. (c) 2016 APA, all rights reserved).

Using Cochran's Z Statistic to Test the Kernel-Smoothed Item Response Function Differences between Focal and Reference Groups

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Zheng, Yinggan; Gierl, Mark J.; Cui, Ying

2010-01-01

This study combined the kernel smoothing procedure and a nonparametric differential item functioning statistic--Cochran's Z--to statistically test the difference between the kernel-smoothed item response functions for reference and focal groups. Simulation studies were conducted to investigate the Type I error and power of the proposed…

Local context effects during emotional item directed forgetting in younger and older adults.

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Gallant, Sara N; Dyson, Benjamin J; Yang, Lixia

2017-09-01

This paper explored the differential sensitivity young and older adults exhibit to the local context of items entering memory. We examined trial-to-trial performance during an item directed forgetting task for positive, negative, and neutral (or baseline) words each cued as either to-be-remembered (TBR) or to-be-forgotten (TBF). This allowed us to focus on how variations in emotional valence (independent of arousal) and instruction (TBR vs. TBF) of the previous item (trial n-1) impacted memory for the current item (trial n) during encoding. Different from research showing impairing effects of emotional arousal, both age groups showed a memorial boost for stimuli when preceded by items high in positive or negative valence relative to those preceded by neutral items. This advantage was particularly prominent for neutral trial n items that followed emotional items suggesting that, regardless of age, neutral memories may be strengthened by a local context that is high in valence. A trending age difference also emerged with older adults showing greater sensitivity when encoding instructions changed between trial n-1 and n. Results are discussed in light of age-related theories of cognitive and emotional processing, highlighting the need to consider the dynamic, moment-to-moment fluctuations of these systems.

A stochastic model for identifying differential gene pair co-expression patterns in prostate cancer progression

Directory of Open Access Journals (Sweden)

Mao Yu

2009-07-01

Full Text Available Abstract Background The identification of gene differential co-expression patterns between cancer stages is a newly developing method to reveal the underlying molecular mechanisms of carcinogenesis. Most researches of this subject lack an algorithm useful for performing a statistical significance assessment involving cancer progression. Lacking this specific algorithm is apparently absent in identifying precise gene pairs correlating to cancer progression. Results In this investigation we studied gene pair co-expression change by using a stochastic process model for approximating the underlying dynamic procedure of the co-expression change during cancer progression. Also, we presented a novel analytical method named 'Stochastic process model for Identifying differentially co-expressed Gene pair' (SIG method. This method has been applied to two well known prostate cancer data sets: hormone sensitive versus hormone resistant, and healthy versus cancerous. From these data sets, 428,582 gene pairs and 303,992 gene pairs were identified respectively. Afterwards, we used two different current statistical methods to the same data sets, which were developed to identify gene pair differential co-expression and did not consider cancer progression in algorithm. We then compared these results from three different perspectives: progression analysis, gene pair identification effectiveness analysis, and pathway enrichment analysis. Statistical methods were used to quantify the quality and performance of these different perspectives. They included: Re-identification Scale (RS and Progression Score (PS in progression analysis, True Positive Rate (TPR in gene pair analysis, and Pathway Enrichment Score (PES in pathway analysis. Our results show small values of RS and large values of PS, TPR, and PES; thus, suggesting that gene pairs identified by the SIG method are highly correlated with cancer progression, and highly enriched in disease-specific pathways. From

Item Response Theory analysis of Fagerström Test for Cigarette Dependence.

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Svicher, Andrea; Cosci, Fiammetta; Giannini, Marco; Pistelli, Francesco; Fagerström, Karl

2018-02-01

The Fagerström Test for Cigarette Dependence (FTCD) and the Heaviness of Smoking Index (HSI) are the gold standard measures to assess cigarette dependence. However, FTCD reliability and factor structure have been questioned and HSI psychometric properties are in need of further investigations. The present study examined the psychometrics properties of the FTCD and the HSI via the Item Response Theory. The study was a secondary analysis of data collected in 862 Italian daily smokers. Confirmatory factor analysis was run to evaluate the dimensionality of FTCD. A Grade Response Model was applied to FTCD and HSI to verify the fit to the data. Both item and test functioning were analyzed and item statistics, Test Information Function, and scale reliabilities were calculated. Mokken Scale Analysis was applied to estimate homogeneity and Loevinger's coefficients were calculated. The FTCD showed unidimensionality and homogeneity for most of the items and for the total score. It also showed high sensitivity and good reliability from medium to high levels of cigarette dependence, although problems related to some items (i.e., items 3 and 5) were evident. HSI had good homogeneity, adequate item functioning, and high reliability from medium to high levels of cigarette dependence. Significant Differential Item Functioning was found for items 1, 4, 5 of the FTCD and for both items of HSI. HSI seems highly recommended in clinical settings addressed to heavy smokers while FTCD would be better used in smokers with a level of cigarette dependence ranging between low and high. Copyright © 2017 Elsevier Ltd. All rights reserved.

Proximity-based differential single cell analysis of the niche to identify stem/progenitor cell regulators

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Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Celso, Cristina Lo; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-fu; Scadden, David T

2016-01-01

SUMMARY Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on differential single-cell gene expression analysis of mesenchymal osteolineage cells close to and further removed from hematopoietic stem/progenitor cells to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. Amongst the genes which were preferentially expressed in proximal cells, we functionally examined three secreted or cell surface molecules not previously connected to HSPC biology: the secreted RNase Angiogenin, the cytokine IL18 and the adhesion molecule Embigin and discovered that all of these factors are HSPC quiescence regulators. Our proximity-based differential single cell approach therefore reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance understanding of microenvironmental regulation of stem cell function. PMID:27524439

Gender Differences in Scientific Literacy of HKPISA 2006: A Multidimensional Differential Item Functioning and Multilevel Mediation Study

Science.gov (United States)

Wong, Kwan Yin

The aim of this study is to investigate the effect of gender differences of 15-year-old students on scientific literacy and their impacts on students’ motivation to pursue science education and careers (Future-oriented Science Motivation) in Hong Kong. The data for this study was collected from the Program for International Student Assessment in Hong Kong (HKPISA). It was carried out in 2006. A total of 4,645 students were randomly selected from 146 secondary schools including government, aided and private schools by two-stage stratified sampling method for the assessment. HKPISA 2006, like most of other large-scale international assessments, presents its assessment frameworks in multidimensional subscales. To fulfill the requirements of this multidimensional assessment framework, this study deployed new approaches to model and investigate gender differences in cognitive and affective latent traits of scientific literacy by using multidimensional differential item functioning (MDIF) and multilevel mediation (MLM). Compared with mean score difference t-test, MDIF improves the precision of each subscales measure at item level and the gender differences in science performance can be accurately estimated. In the light of Eccles et al (1983) Expectancy-value Model of Achievement-related Choices (Eccles’ Model), MLM examines the pattern of gender effects on Future-oriented Science Motivation mediated through cognitive and affective factors. As for MLM investigation, Single-Group Confirmatory Factor Analysis (Single-Group CFA) was used to confirm the applicability and validity of six affective factors which was, originally prepared by OECD. These six factors are Science Self-concept, Personal Value of Science, Interest in Science Learning, Enjoyment of Science Learning, Instrumental Motivation to Learn Science and Future-oriented Science Motivation. Then, Multiple Group CFA was used to verify measurement invariance of these factors across gender groups. The results of

Work ability as prognostic risk marker of disability pension: single-item work ability score versus multi-item work ability index.

Science.gov (United States)

Roelen, Corné A M; van Rhenen, Willem; Groothoff, Johan W; van der Klink, Jac J L; Twisk, Jos W R; Heymans, Martijn W

2014-07-01

Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP. This prospective cohort study comprised 11 537 male construction workers, who completed the WAI at baseline and reported DP after a mean 2.3 years of follow-up. WAS and WAI were calibrated for DP risk predictions with the Hosmer-Lemeshow (H-L) test and their ability to discriminate between high- and low-risk construction workers was investigated with the area under the receiver operating characteristic curve (AUC). At follow-up, 336 (3%) construction workers reported DP. Both WAS [odds ratio (OR) 0.72, 95% confidence interval (95% CI) 0.66-0.78] and WAI (OR 0.57, 95% CI 0.52-0.63) scores were associated with DP at follow-up. The WAS showed miscalibration (H-L model χ (�)=10.60; df=3; P=0.01) and poorly discriminated between high- and low-risk construction workers (AUC 0.67, 95% CI 0.64-0.70). In contrast, calibration (H-L model χ �=8.20; df=8; P=0.41) and discrimination (AUC 0.78, 95% CI 0.75-0.80) were both adequate for the WAI. Although associated with the risk of future DP, the single-item WAS poorly identified male construction workers at risk of DP. We recommend using the multi-item WAI to screen for risk of DP in occupational health practice.

Methodology for the development and calibration of the SCI-QOL item banks.

Science.gov (United States)

Tulsky, David S; Kisala, Pamela A; Victorson, David; Choi, Seung W; Gershon, Richard; Heinemann, Allen W; Cella, David

2015-05-01

To develop a comprehensive, psychometrically sound, and conceptually grounded patient reported outcomes (PRO) measurement system for individuals with spinal cord injury (SCI). Individual interviews (n=44) and focus groups (n=65 individuals with SCI and n=42 SCI clinicians) were used to select key domains for inclusion and to develop PRO items. Verbatim items from other cutting-edge measurement systems (i.e. PROMIS, Neuro-QOL) were included to facilitate linkage and cross-population comparison. Items were field tested in a large sample of individuals with traumatic SCI (n=877). Dimensionality was assessed with confirmatory factor analysis. Local item dependence and differential item functioning were assessed, and items were calibrated using the item response theory (IRT) graded response model. Finally, computer adaptive tests (CATs) and short forms were administered in a new sample (n=245) to assess test-retest reliability and stability. A calibration sample of 877 individuals with traumatic SCI across five SCI Model Systems sites and one Department of Veterans Affairs medical center completed SCI-QOL items in interview format. We developed 14 unidimensional calibrated item banks and 3 calibrated scales across physical, emotional, and social health domains. When combined with the five Spinal Cord Injury--Functional Index physical function banks, the final SCI-QOL system consists of 22 IRT-calibrated item banks/scales. Item banks may be administered as CATs or short forms. Scales may be administered in a fixed-length format only. The SCI-QOL measurement system provides SCI researchers and clinicians with a comprehensive, relevant and psychometrically robust system for measurement of physical-medical, physical-functional, emotional, and social outcomes. All SCI-QOL instruments are freely available on Assessment CenterSM.

Binary classification of items of interest in a repeatable process

Science.gov (United States)

Abell, Jeffrey A.; Spicer, John Patrick; Wincek, Michael Anthony; Wang, Hui; Chakraborty, Debejyo

2014-06-24

A system includes host and learning machines in electrical communication with sensors positioned with respect to an item of interest, e.g., a weld, and memory. The host executes instructions from memory to predict a binary quality status of the item. The learning machine receives signals from the sensor(s), identifies candidate features, and extracts features from the candidates that are more predictive of the binary quality status relative to other candidate features. The learning machine maps the extracted features to a dimensional space that includes most of the items from a passing binary class and excludes all or most of the items from a failing binary class. The host also compares the received signals for a subsequent item of interest to the dimensional space to thereby predict, in real time, the binary quality status of the subsequent item of interest.

Development and evaluation of CAHPS survey items assessing how well healthcare providers address health literacy.

Science.gov (United States)

Weidmer, Beverly A; Brach, Cindy; Hays, Ron D

2012-09-01

The complexity of health information often exceeds patients' skills to understand and use it. To develop survey items assessing how well healthcare providers communicate health information. Domains and items for the Consumer Assessment of Healthcare Providers and Systems (CAHPS) Item Set for Addressing Health Literacy were identified through an environmental scan and input from stakeholders. The draft item set was translated into Spanish and pretested in both English and Spanish. The revised item set was field tested with a randomly selected sample of adult patients from 2 sites using mail and telephonic data collection. Item-scale correlations, confirmatory factor analysis, and internal consistency reliability estimates were estimated to assess how well the survey items performed and identify composite measures. Finally, we regressed the CAHPS global rating of the provider item on the CAHPS core communication composite and the new health literacy composites. A total of 601 completed surveys were obtained (52% response rate). Two composite measures were identified: (1) Communication to Improve Health Literacy (16 items); and (2) How Well Providers Communicate About Medicines (6 items). These 2 composites were significantly uniquely associated with the global rating of the provider (communication to improve health literacy: PLiteracy composite accounted for 90% of the variance of the original 16-item composite. This study provides support for reliability and validity of the CAHPS Item Set for Addressing Health Literacy. These items can serve to assess whether healthcare providers have communicated effectively with their patients and as a tool for quality improvement.

Converging evidence for control of color-word Stroop interference at the item level.

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Bugg, Julie M; Hutchison, Keith A

2013-04-01

Prior studies have shown that cognitive control is implemented at the list and context levels in the color-word Stroop task. At first blush, the finding that Stroop interference is reduced for mostly incongruent items as compared with mostly congruent items (i.e., the item-specific proportion congruence [ISPC] effect) appears to provide evidence for yet a third level of control, which modulates word reading at the item level. However, evidence to date favors the view that ISPC effects reflect the rapid prediction of high-contingency responses and not item-specific control. In Experiment 1, we first show that an ISPC effect is obtained when the relevant dimension (i.e., color) signals proportion congruency, a problematic pattern for theories based on differential response contingencies. In Experiment 2, we replicate and extend this pattern by showing that item-specific control settings transfer to new stimuli, ruling out alternative frequency-based accounts. In Experiment 3, we revert to the traditional design in which the irrelevant dimension (i.e., word) signals proportion congruency. Evidence for item-specific control, including transfer of the ISPC effect to new stimuli, is apparent when 4-item sets are employed but not when 2-item sets are employed. We attribute this pattern to the absence of high-contingency responses on incongruent trials in the 4-item set. These novel findings provide converging evidence for reactive control of color-word Stroop interference at the item level, reveal theoretically important factors that modulate reliance on item-specific control versus contingency learning, and suggest an update to the item-specific control account (Bugg, Jacoby, & Chanani, 2011).

Developing and testing items for the South African Personality Inventory (SAPI

Directory of Open Access Journals (Sweden)

Carin Hill

2013-11-01

Research purpose: This article reports on the process of identifying items for, and provides a quantitative evaluation of, the South African Personality Inventory (SAPI items. Motivation for the study: The study intended to develop an indigenous and psychometrically sound personality instrument that adheres to the requirements of South African legislation and excludes cultural bias. Research design, approach and method: The authors used a cross-sectional design. They measured the nine SAPI clusters identified in the qualitative stage of the SAPI project in 11 separate quantitative studies. Convenience sampling yielded 6735 participants. Statistical analysis focused on the construct validity and reliability of items. The authors eliminated items that showed poor performance, based on common psychometric criteria, and selected the best performing items to form part of the final version of the SAPI. Main findings: The authors developed 2573 items from the nine SAPI clusters. Of these, 2268 items were valid and reliable representations of the SAPI facets. Practical/managerial implications: The authors developed a large item pool. It measures personality in South Africa. Researchers can refine it for the SAPI. Furthermore, the project illustrates an approach that researchers can use in projects that aim to develop culturally-informed psychological measures. Contribution/value-add: Personality assessment is important for recruiting, selecting and developing employees. This study contributes to the current knowledge about the early processes researchers follow when they develop a personality instrument that measures personality fairly in different cultural groups, as the SAPI does.

Ethical imperatives against item restriction in the Supplemental Nutrition Assistance Program.

Science.gov (United States)

Chrisinger, Benjamin W

2017-07-01

The Supplemental Nutrition Assistance Program (SNAP, formerly known as food stamps) is the federal government's largest form of food assistance, and a frequent focus of political and scholarly debate. Previous discourse in the public health community and recent proposals in state legislatures have suggested limiting the use of SNAP benefits on unhealthy food items, such as sugar-sweetened beverages (SSBs). This paper identifies two possible underlying motivations for item restriction, health and morals, and analyzes the level of empirical support for claims about the current state of the program, as well as expectations about how item restriction would change participant outcomes. It also assesses how item restriction would reduce individual agency of low-income individuals, and identifies mechanisms by which this may adversely affect program participants. Finally, this paper offers alternative policies to promote healthier purchasing and eating among SNAP participants that can be pursued without reducing individual agency. Health advocates and officials must more fully weigh the attendant risks of implementing SNAP item restrictions, including the reduction of individual agency of a vulnerable population. Copyright © 2017 Elsevier Inc. All rights reserved.

Selection of material balance areas and item control areas

International Nuclear Information System (INIS)

1975-04-01

Section 70.58, ''Fundamental Nuclear Material Controls,'' of 10 CFR Part 70, ''Special Nuclear Material,'' requires certain licensees authorized to possess more than one effective kilogram of special nuclear material to establish Material Balance Areas (MBAs) or Item Control Areas (ICAs) for the physical and administrative control of nuclear materials. This section requires that: (1) each MBA be an identifiable physical area such that the quantity of nuclear material being moved into or out of the MBA is represented by a measured value; (2) the number of MBAs be sufficient to localize nuclear material losses or thefts and identify the mechanisms; (3) the custody of all nuclear material within an MBA or ICA be the responsibility of a single designated individual; and (4) ICAs be established according to the same criteria as MBAs except that control into and out of such areas would be by item identity and count for previously determined special nuclear material quantities, the validity of which must be ensured by tamper-safing unless the items are sealed sources. This guide describes bases acceptable to the NRC staff for the selection of material balance areas and item control areas. (U.S.)

The cultural fairness of the 12-item General Health Questionnaire among diverse adolescents.

Science.gov (United States)

Bowe, Anica

2017-01-01

The 12-item general health questionnaire (GHQ-12) was used in the Longitudinal Study of Young People in England (LSYPE; N = 15,770) to collect measures on adolescent mental health. Given the debate in current literature regarding the dimensionality of the GHQ-12, this study examined the cultural sensitivity of the instrument at the item level for each of the 7 major ethnic groups within the database. This study used a hybrid approach of ordinal logistic regression and item response theory (IRT) to examine the presence of differential item functioning (DIF) on the questionnaire. Results demonstrated that uniform, nonuniform, and overall DIF were present on items between White and Asian adolescents (7 items), White and Black Caribbean adolescents (1 item), and White and Black African adolescents (7 items), however all McFadden's pseudo R² effect size estimates indicated that the DIF was negligible. Overall, there were cumulative small scale level effects for the Mixed/Biracial, Asian, and Black African groups, but in each case the bias was only marginal. Findings demonstrate that the GHQ-12 can be considered culturally sensitive for adolescents from diverse ethnic groups in England, but follow-up studies are necessary. Implications for future education and health policies as well as the use of IR-based approaches for psychological instruments are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Evaluation of the Psychometric Properties of the Asian Adolescent Depression Scale and Construction of a Short Form: An Item Response Theory Analysis.

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Lo, Barbara Chuen Yee; Zhao, Yue; Kwok, Alice Wai Yee; Chan, Wai; Chan, Calais Kin Yuen

2017-07-01

The present study applied item response theory to examine the psychometric properties of the Asian Adolescent Depression Scale and to construct a short form among 1,084 teenagers recruited from secondary schools in Hong Kong. Findings suggested that some items of the full form reflected higher levels of severity and were more discriminating than others, and the Asian Adolescent Depression Scale was useful in measuring a broad range of depressive severity in community youths. Differential item functioning emerged in several items where females reported higher depressive severity than males. In the short form construction, preliminary validation suggested that, relative to the 20-item full form, our derived short form offered significantly greater diagnostic performance and stronger discriminatory ability in differentiating depressed and nondepressed groups, and simultaneously maintained adequate measurement precision with a reduced response burden in assessing depression in the Asian adolescents. Cultural variance in depressive symptomatology and clinical implications are discussed.

Development and psychometric characteristics of the SCI-QOL Ability to Participate and Satisfaction with Social Roles and Activities item banks and short forms.

Science.gov (United States)

Heinemann, Allen W; Kisala, Pamela A; Hahn, Elizabeth A; Tulsky, David S

2015-05-01

To develop a spinal cord injury (SCI)-focused version of PROMIS and Neuro-QOL social domain item banks; evaluate the psychometric properties of items developed for adults with SCI; and report information to facilitate clinical and research use. We used a mixed-methods design to develop and evaluate Ability to Participate in Social Roles and Activities and Satisfaction with Social Roles and Activities items. Focus groups helped define the constructs; cognitive interviews helped revise items; and confirmatory factor analysis and item response theory methods helped calibrate item banks and evaluate differential item functioning related to demographic and injury characteristics. Five SCI Model System sites and one Veterans Administration medical center. The calibration sample consisted of 641 individuals; a reliability sample consisted of 245 individuals residing in the community. A subset of 27 Ability to Participate and 35 Satisfaction items demonstrated good measurement properties and negligible differential item functioning related to demographic and injury characteristics. The SCI-specific measures correlate strongly with the PROMIS and Neuro-QOL versions. Ten item short forms correlate >0.96 with the full banks. Variable-length CATs with a minimum of 4 items, variable-length CATs with a minimum of 8 items, fixed-length CATs of 10 items, and the 10-item short forms demonstrate construct coverage and measurement error that is comparable to the full item bank. The Ability to Participate and Satisfaction with Social Roles and Activities CATs and short forms demonstrate excellent psychometric properties and are suitable for clinical and research applications.

78 FR 76067 - Defense Federal Acquisition Regulation Supplement: Item Unique Identifier Update (DFARS Case 2011...

Science.gov (United States)

2013-12-16

... emphasizes the importance of quantifying both costs and benefits, of reducing costs, of harmonizing rules...) Ensures item level traceability throughout lifecycle to strengthen supply chain integrity, enhance cyber security, and combat counterfeiting. 0 3. Section 211.274-2 is amended by-- 0 a. Revising the section...

77 FR 35921 - Defense Federal Acquisition Regulation Supplement: Item Unique Identifier Update (DFARS Case 2011...

Science.gov (United States)

2012-06-15

... lifecycle to strengthen supply chain integrity, enhance cyber security and combat counterfeiting. 4. Section... include your name, company name (if any), and ``DFARS Case 2011-D055'' on your attached document. [cir... businesses registered in the Item Unique Identification Registry, out of 2,431 total companies registered...

Item response theory analysis of the mechanics baseline test

Science.gov (United States)

Cardamone, Caroline N.; Abbott, Jonathan E.; Rayyan, Saif; Seaton, Daniel T.; Pawl, Andrew; Pritchard, David E.

2012-02-01

Item response theory is useful in both the development and evaluation of assessments and in computing standardized measures of student performance. In item response theory, individual parameters (difficulty, discrimination) for each item or question are fit by item response models. These parameters provide a means for evaluating a test and offer a better measure of student skill than a raw test score, because each skill calculation considers not only the number of questions answered correctly, but the individual properties of all questions answered. Here, we present the results from an analysis of the Mechanics Baseline Test given at MIT during 2005-2010. Using the item parameters, we identify questions on the Mechanics Baseline Test that are not effective in discriminating between MIT students of different abilities. We show that a limited subset of the highest quality questions on the Mechanics Baseline Test returns accurate measures of student skill. We compare student skills as determined by item response theory to the more traditional measurement of the raw score and show that a comparable measure of learning gain can be computed.

Item analysis of ADAS-Cog: effect of baseline cognitive impairment in a clinical AD trial.

Science.gov (United States)

Sevigny, Jeffrey J; Peng, Yahong; Liu, Lian; Lines, Christopher R

2010-03-01

We explored the association of Alzheimer's disease (AD) Assessment Scale (ADAS-Cog) item scores with AD severity using cross-sectional and longitudinal data from the same study. Post hoc analyses were performed using placebo data from a 12-month trial of patients with mild-to-moderate AD (N =281 randomized, N =209 completed). Baseline distributions of ADAS-Cog item scores by Mini-Mental State Examination (MMSE) score and Clinical Dementia Rating (CDR) sum of boxes score (measures of dementia severity) were estimated using local and nonparametric regressions. Mixed-effect models were used to characterize ADAS-Cog item score changes over time by dementia severity (MMSE: mild =21-26, moderate =14-20; global CDR: mild =0.5-1, moderate =2). In the cross-sectional analysis of baseline ADAS-Cog item scores, orientation was the most sensitive item to differentiate patients across levels of cognitive impairment. Several items showed a ceiling effect, particularly in milder AD. In the longitudinal analysis of change scores over 12 months, orientation was the only item with noticeable decline (8%-10%) in mild AD. Most items showed modest declines (5%-20%) in moderate AD.

Assessment of the psychometrics of a PROMIS item bank: self-efficacy for managing daily activities.

Science.gov (United States)

Hong, Ickpyo; Velozo, Craig A; Li, Chih-Ying; Romero, Sergio; Gruber-Baldini, Ann L; Shulman, Lisa M

2016-09-01

The aim of this study is to investigate the psychometrics of the Patient-Reported Outcomes Measurement Information System self-efficacy for managing daily activities item bank. The item pool was field tested on a sample of 1087 participants via internet (n = 250) and in-clinic (n = 837) surveys. All participants reported having at least one chronic health condition. The 35 item pool was investigated for dimensionality (confirmatory factor analyses, CFA and exploratory factor analysis, EFA), item-total correlations, local independence, precision, and differential item functioning (DIF) across gender, race, ethnicity, age groups, data collection modes, and neurological chronic conditions (McFadden Pseudo R (2) less than 10 %). The item pool met two of the four CFA fit criteria (CFI = 0.952 and SRMR = 0.07). EFA analysis found a dominant first factor (eigenvalue = 24.34) and the ratio of first to second eigenvalue was 12.4. The item pool demonstrated good item-total correlations (0.59-0.85) and acceptable internal consistency (Cronbach's alpha = 0.97). The item pool maintained its precision (reliability over 0.90) across a wide range of theta (3.70), and there was no significant DIF. The findings indicated the item pool has sound psychometric properties and the test items are eligible for development of computerized adaptive testing and short forms.

41 CFR 102-36.455 - How do we report excess shelf-life items?

Science.gov (United States)

2010-07-01

... shelf-life items? 102-36.455 Section 102-36.455 Public Contracts and Property Management Federal...-DISPOSITION OF EXCESS PERSONAL PROPERTY Personal Property Whose Disposal Requires Special Handling Shelf-Life Items § 102-36.455 How do we report excess shelf-life items? You must identify the property as shelf...

Effects of Learning Experience on Forgetting Rates of Item and Associative Memories

Science.gov (United States)

Yang, Jiongjiong; Zhan, Lexia; Wang, Yingying; Du, Xiaoya; Zhou, Wenxi; Ning, Xueling; Sun, Qing; Moscovitch, Morris

2016-01-01

Are associative memories forgotten more quickly than item memories, and does the level of original learning differentially influence forgetting rates? In this study, we addressed these questions by having participants learn single words and word pairs once (Experiment 1), three times (Experiment 2), and six times (Experiment 3) in a massed…

The effects of value on context-item associative memory in younger and older adults.

Science.gov (United States)

Hennessee, Joseph P; Knowlton, Barbara J; Castel, Alan D

2018-02-01

Valuable items are often remembered better than items that are less valuable by both older and younger adults, but older adults typically show deficits in binding. Here, we examine whether value affects the quality of recognition memory and the binding of incidental details to valuable items. In Experiment 1, participants learned English words each associated with a point-value they earned for correct recognition with the goal of maximizing their score. In Experiment 2, value was manipulated by presenting items that were either congruent or incongruent with an imagined state of physiological need (e.g., hunger). In Experiment 1, point-value was associated with enhanced recollection in both age groups. Memory for the color associated with the word was in fact reduced for high-value recollected items compared with low-value recollected items, suggesting value selectively enhances binding of task-relevant details. In Experiment 2, memory for learned images was enhanced by value in both age groups. However, value differentially enhanced binding of an imagined context to the item in younger and older adults, with a strong trend for increased binding in younger adults only. These findings suggest that value enhances episodic encoding in both older and younger adults but that binding of associated details may be reduced for valuable items compared to less valuable items, particularly in older adults. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Calibration of the PROMIS physical function item bank in Dutch patients with rheumatoid arthritis.

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Martijn A H Oude Voshaar

Full Text Available OBJECTIVE: To calibrate the Dutch-Flemish version of the PROMIS physical function (PF item bank in patients with rheumatoid arthritis (RA and to evaluate cross-cultural measurement equivalence with US general population and RA data. METHODS: Data were collected from RA patients enrolled in the Dutch DREAM registry. An incomplete longitudinal anchored design was used where patients completed all 121 items of the item bank over the course of three waves of data collection. Item responses were fit to a generalized partial credit model adapted for longitudinal data and the item parameters were examined for differential item functioning (DIF across country, age, and sex. RESULTS: In total, 690 patients participated in the study at time point 1 (T2, N = 489; T3, N = 311. The item bank could be successfully fitted to a generalized partial credit model, with the number of misfitting items falling within acceptable limits. Seven items demonstrated DIF for sex, while 5 items showed DIF for age in the Dutch RA sample. Twenty-five (20% items were flagged for cross-cultural DIF compared to the US general population. However, the impact of observed DIF on total physical function estimates was negligible. DISCUSSION: The results of this study showed that the PROMIS PF item bank adequately fit a unidimensional IRT model which provides support for applications that require invariant estimates of physical function, such as computer adaptive testing and targeted short forms. More studies are needed to further investigate the cross-cultural applicability of the US-based PROMIS calibration and standardized metric.

Proximity-Based Differential Single-Cell Analysis of the Niche to Identify Stem/Progenitor Cell Regulators.

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Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel A; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Lo Celso, Cristina; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-Fu; Scadden, David T

2016-10-06

Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on the differential single-cell gene expression analysis of mesenchymal osteolineage cells close to, and further removed from, hematopoietic stem/progenitor cells (HSPCs) to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. We functionally examined, among the genes that were preferentially expressed in proximal cells, three secreted or cell-surface molecules not previously connected to HSPC biology-the secreted RNase angiogenin, the cytokine IL18, and the adhesion molecule Embigin-and discovered that all of these factors are HSPC quiescence regulators. Therefore, our proximity-based differential single-cell approach reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance the understanding of microenvironmental regulation of stem cell function. Copyright © 2016 Elsevier Inc. All rights reserved.

Detecting Differential Person Functioning in Emotional Intelligence

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Alsmadi, Yahia M.; Alsmadi, Abdalla A.

2009-01-01

Differential Item Functioning (DIF) is a widely used term in test development literature. It is very important to analyze test's data for DIF because It is a serious threat to validity. If the same data matrix was transposed, similar analysis can be carried for Differential Person Functioning (DPF). The purpose of this paper is to introduce and…

The Single Item Literacy Screener: Evaluation of a brief instrument to identify limited reading ability

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Chew Lisa D

2006-03-01

Full Text Available Abstract Background Reading skills are important for accessing health information, using health care services, managing one's health and achieving desirable health outcomes. Our objective was to assess the diagnostic accuracy of the Single Item Literacy Screener (SILS to identify limited reading ability, one component of health literacy, as measured by the S-TOFHLA. Methods Cross-sectional interview with 999 adults with diabetes residing in Vermont and bordering states. Participants were randomly recruited from Primary Care practices in the Vermont Diabetes Information System June 2003 – December 2004. The main outcome was limited reading ability. The primary predictor was the SILS. Results Of the 999 persons screened, 169 (17% had limited reading ability. The sensitivity of the SILS in detecting limited reading ability was 54% [95% CI: 47%, 61%] and the specificity was 83% [95% CI: 81%, 86%] with an area under the Receiver Operating Characteristics Curve (ROC of 0.73 [95% CI: 0.69, 0.78]. Seven hundred seventy (77% screened negative on the SILS and 692 of these subjects had adequate reading skills (negative predictive value = 0.90 [95% CI: 0.88, 0.92]. Of the 229 who scored positive on the SILS, 92 had limited reading ability (positive predictive value = 0.4 [95% CI: 0.34, 0.47]. Conclusion The SILS is a simple instrument designed to identify patients with limited reading ability who need help reading health-related materials. The SILS performs moderately well at ruling out limited reading ability in adults and allows providers to target additional assessment of health literacy skills to those most in need. Further study of the use of the SILS in clinical settings and with more diverse populations is warranted.

17 CFR 229.402 - (Item 402) Executive compensation.

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2010-04-01

... which its securities are listed or traded. (2) All compensation covered. This Item requires clear... different currency, a footnote must be provided to identify that currency and describe the rate and...

Solving Differential Equations Analytically. Elementary Differential Equations. Modules and Monographs in Undergraduate Mathematics and Its Applications Project. UMAP Unit 335.

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Goldston, J. W.

This unit introduces analytic solutions of ordinary differential equations. The objective is to enable the student to decide whether a given function solves a given differential equation. Examples of problems from biology and chemistry are covered. Problem sets, quizzes, and a model exam are included, and answers to all items are provided. The…

Integrating mean and variance heterogeneities to identify differentially expressed genes.

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Ouyang, Weiwei; An, Qiang; Zhao, Jinying; Qin, Huaizhen

2016-12-06

In functional genomics studies, tests on mean heterogeneity have been widely employed to identify differentially expressed genes with distinct mean expression levels under different experimental conditions. Variance heterogeneity (aka, the difference between condition-specific variances) of gene expression levels is simply neglected or calibrated for as an impediment. The mean heterogeneity in the expression level of a gene reflects one aspect of its distribution alteration; and variance heterogeneity induced by condition change may reflect another aspect. Change in condition may alter both mean and some higher-order characteristics of the distributions of expression levels of susceptible genes. In this report, we put forth a conception of mean-variance differentially expressed (MVDE) genes, whose expression means and variances are sensitive to the change in experimental condition. We mathematically proved the null independence of existent mean heterogeneity tests and variance heterogeneity tests. Based on the independence, we proposed an integrative mean-variance test (IMVT) to combine gene-wise mean heterogeneity and variance heterogeneity induced by condition change. The IMVT outperformed its competitors under comprehensive simulations of normality and Laplace settings. For moderate samples, the IMVT well controlled type I error rates, and so did existent mean heterogeneity test (i.e., the Welch t test (WT), the moderated Welch t test (MWT)) and the procedure of separate tests on mean and variance heterogeneities (SMVT), but the likelihood ratio test (LRT) severely inflated type I error rates. In presence of variance heterogeneity, the IMVT appeared noticeably more powerful than all the valid mean heterogeneity tests. Application to the gene profiles of peripheral circulating B raised solid evidence of informative variance heterogeneity. After adjusting for background data structure, the IMVT replicated previous discoveries and identified novel experiment

Testing the Item-Order Account of Design Effects Using the Production Effect

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Jonker, Tanya R.; Levene, Merrick; MacLeod, Colin M.

2014-01-01

A number of memory phenomena evident in recall in within-subject, mixed-lists designs are reduced or eliminated in between-subject, pure-list designs. The item-order account (McDaniel & Bugg, 2008) proposes that differential retention of order information might underlie this pattern. According to this account, order information may be encoded…

Distinguishing Differential Testlet Functioning from Differential Bundle Functioning Using the Multilevel Measurement Model

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Beretvas, S. Natasha; Walker, Cindy M.

2012-01-01

This study extends the multilevel measurement model to handle testlet-based dependencies. A flexible two-level testlet response model (the MMMT-2 model) for dichotomous items is introduced that permits assessment of differential testlet functioning (DTLF). A distinction is made between this study's conceptualization of DTLF and that of…

Robust Measurement via A Fused Latent and Graphical Item Response Theory Model.

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Chen, Yunxiao; Li, Xiaoou; Liu, Jingchen; Ying, Zhiliang

2018-03-12

Item response theory (IRT) plays an important role in psychological and educational measurement. Unlike the classical testing theory, IRT models aggregate the item level information, yielding more accurate measurements. Most IRT models assume local independence, an assumption not likely to be satisfied in practice, especially when the number of items is large. Results in the literature and simulation studies in this paper reveal that misspecifying the local independence assumption may result in inaccurate measurements and differential item functioning. To provide more robust measurements, we propose an integrated approach by adding a graphical component to a multidimensional IRT model that can offset the effect of unknown local dependence. The new model contains a confirmatory latent variable component, which measures the targeted latent traits, and a graphical component, which captures the local dependence. An efficient proximal algorithm is proposed for the parameter estimation and structure learning of the local dependence. This approach can substantially improve the measurement, given no prior information on the local dependence structure. The model can be applied to measure both a unidimensional latent trait and multidimensional latent traits.

A Comprehensive List of Items to be Included on a Pediatric Drug Monograph.

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Kelly, Lauren E; Ito, Shinya; Woods, David; Nunn, Anthony J; Taketomo, Carol; de Hoog, Matthijs; Offringa, Martin

2017-01-01

Children require special considerations for drug prescribing. Drug information summarized in a formulary containing drug monographs is essential for safe and effective prescribing. Currently, little is known about the information needs of those who prescribe and administer medicines to children. Our primary objective was to identify a list of important and relevant items to be included in a pediatric drug monograph. Following the establishment of an expert steering committee and an environmental scan of adult and pediatric formulary monograph items, 46 participants from 25 countries were invited to complete a 2-round Delphi survey. Questions regarding source of prescribing information and importance of items were recorded. An international consensus meeting to vote on and finalize the items list with the steering committee followed. Pediatric formularies are most commonly the first resource consulted for information on medication used in children by 31 Delphi participants. After the Delphi rounds, 116 items were identified to be included in a comprehensive pediatric drug monograph, including general information, adverse drug reactions, dosages, precautions, drug-drug interactions, formulation, and drug properties. Health care providers identified 116 monograph items as important for prescribing medicines for children by an international consensus-based process. This information will assist in setting standards for the creation of new pediatric drug monographs for international application and for those involved in pediatric formulary development.

The differential item functioning and structural equivalence of a nonverbal cognitive ability test for five language groups

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Pieter Schaap

2011-10-01

Research purpose: The aim of the study was to determine the differential item functioning (DIF and structural equivalence of a nonverbal cognitive ability test (the PiB/SpEEx Observance test [401] for five South African language groups. Motivation for study: Cultural and language group sensitive tests can lead to unfair discrimination and is a contentious workplace issue in South Africa today. Misconceptions about psychometric testing in industry can cause tests to lose credibility if industries do not use a scientifically sound test-by-test evaluation approach. Research design, approach and method: The researcher used a quasi-experimental design and factor analytic and logistic regression techniques to meet the research aims. The study used a convenience sample drawn from industry and an educational institution. Main findings: The main findings of the study show structural equivalence of the test at a holistic level and nonsignificant DIF effect sizes for most of the comparisons that the researcher made. Practical/managerial implications: This research shows that the PIB/SpEEx Observance Test (401 is not completely language insensitive. One should see it rather as a language-reduced test when people from different language groups need testing. Contribution/value-add: The findings provide supporting evidence that nonverbal cognitive tests are plausible alternatives to verbal tests when one compares people from different language groups.

Evaluation of item candidates for a diabetic retinopathy quality of life item bank.

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Fenwick, Eva K; Pesudovs, Konrad; Khadka, Jyoti; Rees, Gwyn; Wong, Tien Y; Lamoureux, Ecosse L

2013-09-01

We are developing an item bank assessing the impact of diabetic retinopathy (DR) on quality of life (QoL) using a rigorous multi-staged process combining qualitative and quantitative methods. We describe here the first two qualitative phases: content development and item evaluation. After a comprehensive literature review, items were generated from four sources: (1) 34 previously validated patient-reported outcome measures; (2) five published qualitative articles; (3) eight focus groups and 18 semi-structured interviews with 57 DR patients; and (4) seven semi-structured interviews with diabetes or ophthalmic experts. Items were then evaluated during 3 stages, namely binning (grouping) and winnowing (reduction) based on key criteria and panel consensus; development of item stems and response options; and pre-testing of items via cognitive interviews with patients. The content development phase yielded 1,165 unique items across 7 QoL domains. After 3 sessions of binning and winnowing, items were reduced to a minimally representative set (n = 312) across 9 domains of QoL: visual symptoms; ocular surface symptoms; activity limitation; mobility; emotional; health concerns; social; convenience; and economic. After 8 cognitive interviews, 42 items were amended resulting in a final set of 314 items. We have employed a systematic approach to develop items for a DR-specific QoL item bank. The psychometric properties of the nine QoL subscales will be assessed using Rasch analysis. The resulting validated item bank will allow clinicians and researchers to better understand the QoL impact of DR and DR therapies from the patient's perspective.

Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank

NARCIS (Netherlands)

Oude Voshaar, Martijn A.H.; Ten Klooster, Peter M.; Vonkeman, Harald E.; van de Laar, Mart A.F.J.

2017-01-01

Objective: Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations. Study

A signal detection-item response theory model for evaluating neuropsychological measures.

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Thomas, Michael L; Brown, Gregory G; Gur, Ruben C; Moore, Tyler M; Patt, Virginie M; Risbrough, Victoria B; Baker, Dewleen G

2018-02-05

Models from signal detection theory are commonly used to score neuropsychological test data, especially tests of recognition memory. Here we show that certain item response theory models can be formulated as signal detection theory models, thus linking two complementary but distinct methodologies. We then use the approach to evaluate the validity (construct representation) of commonly used research measures, demonstrate the impact of conditional error on neuropsychological outcomes, and evaluate measurement bias. Signal detection-item response theory (SD-IRT) models were fitted to recognition memory data for words, faces, and objects. The sample consisted of U.S. Infantry Marines and Navy Corpsmen participating in the Marine Resiliency Study. Data comprised item responses to the Penn Face Memory Test (PFMT; N = 1,338), Penn Word Memory Test (PWMT; N = 1,331), and Visual Object Learning Test (VOLT; N = 1,249), and self-report of past head injury with loss of consciousness. SD-IRT models adequately fitted recognition memory item data across all modalities. Error varied systematically with ability estimates, and distributions of residuals from the regression of memory discrimination onto self-report of past head injury were positively skewed towards regions of larger measurement error. Analyses of differential item functioning revealed little evidence of systematic bias by level of education. SD-IRT models benefit from the measurement rigor of item response theory-which permits the modeling of item difficulty and examinee ability-and from signal detection theory-which provides an interpretive framework encompassing the experimentally validated constructs of memory discrimination and response bias. We used this approach to validate the construct representation of commonly used research measures and to demonstrate how nonoptimized item parameters can lead to erroneous conclusions when interpreting neuropsychological test data. Future work might include the

The role of attention in item-item binding in visual working memory.

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Peterson, Dwight J; Naveh-Benjamin, Moshe

2017-09-01

An important yet unresolved question regarding visual working memory (VWM) relates to whether or not binding processes within VWM require additional attentional resources compared with processing solely the individual components comprising these bindings. Previous findings indicate that binding of surface features (e.g., colored shapes) within VWM is not demanding of resources beyond what is required for single features. However, it is possible that other types of binding, such as the binding of complex, distinct items (e.g., faces and scenes), in VWM may require additional resources. In 3 experiments, we examined VWM item-item binding performance under no load, articulatory suppression, and backward counting using a modified change detection task. Binding performance declined to a greater extent than single-item performance under higher compared with lower levels of concurrent load. The findings from each of these experiments indicate that processing item-item bindings within VWM requires a greater amount of attentional resources compared with single items. These findings also highlight an important distinction between the role of attention in item-item binding within VWM and previous studies of long-term memory (LTM) where declines in single-item and binding test performance are similar under divided attention. The current findings provide novel evidence that the specific type of binding is an important determining factor regarding whether or not VWM binding processes require attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Effects of Item Format and Cognitive Domain on Students' Science Performance in TIMSS 2011

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Liou, Pey-Yan; Bulut, Okan

2017-12-01

The purpose of this study was to examine eighth-grade students' science performance in terms of two test design components, item format, and cognitive domain. The portion of Taiwanese data came from the 2011 administration of the Trends in International Mathematics and Science Study (TIMSS), one of the major international large-scale assessments in science. The item difficulty analysis was initially applied to show the proportion of correct items. A regression-based cumulative link mixed modeling (CLMM) approach was further utilized to estimate the impact of item format, cognitive domain, and their interaction on the students' science scores. The results of the proportion-correct statistics showed that constructed-response items were more difficult than multiple-choice items, and that the reasoning cognitive domain items were more difficult compared to the items in the applying and knowing domains. In terms of the CLMM results, students tended to obtain higher scores when answering constructed-response items as well as items in the applying cognitive domain. When the two predictors and the interaction term were included together, the directions and magnitudes of the predictors on student science performance changed substantially. Plausible explanations for the complex nature of the effects of the two test-design predictors on student science performance are discussed. The results provide practical, empirical-based evidence for test developers, teachers, and stakeholders to be aware of the differential function of item format, cognitive domain, and their interaction in students' science performance.

Calibration of the Dutch-Flemish PROMIS Pain Behavior item bank in patients with chronic pain.

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Crins, M H P; Roorda, L D; Smits, N; de Vet, H C W; Westhovens, R; Cella, D; Cook, K F; Revicki, D; van Leeuwen, J; Boers, M; Dekker, J; Terwee, C B

2016-02-01

The aims of the current study were to calibrate the item parameters of the Dutch-Flemish PROMIS Pain Behavior item bank using a sample of Dutch patients with chronic pain and to evaluate cross-cultural validity between the Dutch-Flemish and the US PROMIS Pain Behavior item banks. Furthermore, reliability and construct validity of the Dutch-Flemish PROMIS Pain Behavior item bank were evaluated. The 39 items in the bank were completed by 1042 Dutch patients with chronic pain. To evaluate unidimensionality, a one-factor confirmatory factor analysis (CFA) was performed. A graded response model (GRM) was used to calibrate the items. To evaluate cross-cultural validity, Differential item functioning (DIF) for language (Dutch vs. English) was evaluated. Reliability of the item bank was also examined and construct validity was studied using several legacy instruments, e.g. the Roland Morris Disability Questionnaire. CFA supported the unidimensionality of the Dutch-Flemish PROMIS Pain Behavior item bank (CFI = 0.960, TLI = 0.958), the data also fit the GRM, and demonstrated good coverage across the pain behavior construct (threshold parameters range: -3.42 to 3.54). Analysis showed good cross-cultural validity (only six DIF items), reliability (Cronbach's α = 0.95) and construct validity (all correlations ≥0.53). The Dutch-Flemish PROMIS Pain Behavior item bank was found to have good cross-cultural validity, reliability and construct validity. The development of the Dutch-Flemish PROMIS Pain Behavior item bank will serve as the basis for Dutch-Flemish PROMIS short forms and computer adaptive testing (CAT). © 2015 European Pain Federation - EFIC®

Análise do funcionamento diferencial dos itens do Exame Nacional do Estudante (ENADE de psicologia de 2006 Differential item functioning of the national student exam for psychology (ENADE 2006

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Ricardo Primi

2010-12-01

Full Text Available Parte do Sistema Nacional de Avaliação das Instituições de Educação Superior considera o desempenho dos estudantes por meio do ENADE. Neste artigo efetuou-se uma análise dos itens da prova do ENADE de psicologia aplicada em 2006 tentando-se detectar itens com funcionamento diferencial (DIF, isto é, itens com problema de equivalência ao medir ingressantes e concluintes e estudantes de instituições públicas e privada. Analisou-se uma amostra de 26.613 estudantes ingressantes e concluintes representativa de todos os cursos do país. Empregou-se a análise de Rasch e regressão logística para se detectar o DIF. Onze itens dos 30 que compunham a prova apresentaram DIF. Dois tipos de DIF ocorreram, um tipo em itens com baixa discriminação e outro em itens com alta discriminação. O subgrupo mais relevante tende a favorecer alunos de instituições públicas. Discute-se também a questão da discriminação elevada como indicativo de DIF.Part of the National Assessment of Institutions of Higher Education considers student performance through ENADE. In this article we performed differential item function analysis of the ENADE that took place in 2006 trying to detect items with problems in measurement equivalence in the assessment of freshman and senior students and from public and private institutions. We analyzed a sample of 26,613 freshmen and seniors representative of all the courses in the country. We used the Rasch analysis and logistic regression to detect DIF. Eleven of the 30 items composing the test showed DIF. Two types of DIF were observed, one occurring in less discriminating items and the other in more discriminating items. The most relevant subgroup of items tends to favor students from public institutions. We also discuss the issue of discrimination parameter being an indicator of DIF.

A Polytomous Item Response Theory Analysis of Social Physique Anxiety Scale

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Fletcher, Richard B.; Crocker, Peter

2014-01-01

The present study investigated the social physique anxiety scale's factor structure and item properties using confirmatory factor analysis and item response theory. An additional aim was to identify differences in response patterns between groups (gender). A large sample of high school students aged 11-15 years (N = 1,529) consisting of n =…

Using item response theory to address vulnerabilities in FFQ.

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Kazman, Josh B; Scott, Jonathan M; Deuster, Patricia A

2017-09-01

The limitations for self-reporting of dietary patterns are widely recognised as a major vulnerability of FFQ and the dietary screeners/scales derived from FFQ. Such instruments can yield inconsistent results to produce questionable interpretations. The present article discusses the value of psychometric approaches and standards in addressing these drawbacks for instruments used to estimate dietary habits and nutrient intake. We argue that a FFQ or screener that treats diet as a 'latent construct' can be optimised for both internal consistency and the value of the research results. Latent constructs, a foundation for item response theory (IRT)-based scales (e.g. Patient Reported Outcomes Measurement Information System) are typically introduced in the design stage of an instrument to elicit critical factors that cannot be observed or measured directly. We propose an iterative approach that uses such modelling to refine FFQ and similar instruments. To that end, we illustrate the benefits of psychometric modelling by using items and data from a sample of 12 370 Soldiers who completed the 2012 US Army Global Assessment Tool (GAT). We used factor analysis to build the scale incorporating five out of eleven survey items. An IRT-driven assessment of response category properties indicates likely problems in the ordering or wording of several response categories. Group comparisons, examined with differential item functioning (DIF), provided evidence of scale validity across each Army sub-population (sex, service component and officer status). Such an approach holds promise for future FFQ.

Identifying patient fear-avoidance beliefs by physical therapists managing patients with low back pain.

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Calley, Darren Q; Jackson, Steven; Collins, Heather; George, Steven Z

2010-12-01

. Therapists' ratings of perceived patient fear-avoidance were not associated with self-reported fear-avoidance scores, showing a potential disconnect between therapist judgments and commonly used fear-avoidance measures. Instead, therapist ratings had small but statistically significant correlations with pain catastrophizing and disability, findings that may support therapists' inability to discriminate fear-avoidance from these other factors. The 2-item screening questions based on fear of physical activity and harm showed potential to identify elevated FABQ physical activity scores. Differential diagnosis, level 2b.

Effects of Reducing the Cognitive Load of Mathematics Test Items on Student Performance

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Susan C. Gillmor

2015-01-01

Full Text Available This study explores a new item-writing framework for improving the validity of math assessment items. The authors transfer insights from Cognitive Load Theory (CLT, traditionally used in instructional design, to educational measurement. Fifteen, multiple-choice math assessment items were modified using research-based strategies for reducing extraneous cognitive load. An experimental design with 222 middle-school students tested the effects of the reduced cognitive load items on student performance and anxiety. Significant findings confirm the main research hypothesis that reducing the cognitive load of math assessment items improves student performance. Three load-reducing item modifications are identified as particularly effective for reducing item difficulty: signalling important information, aesthetic item organization, and removing extraneous content. Load reduction was not shown to impact student anxiety. Implications for classroom assessment and future research are discussed.

Do Self Concept Tests Test Self Concept? An Evaluation of the Validity of Items on the Piers Harris and Coopersmith Measures.

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Lynch, Mervin D.; Chaves, John

Items from Peirs-Harris and Coopersmith self-concept tests were evaluated against independent measures on three self-constructs, idealized, empathic, and worth. Construct measurements were obtained with the semantic differential and D statistic. Ratings were obtained from 381 children, grades 4-6. For each test, item ratings and construct measures…

Temporal Profiling and Pulsed SILAC Labeling Identify Novel Secreted Proteins During Ex Vivo Osteoblast Differentiation of Human Stromal Stem Cells*

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Kristensen, Lars P.; Chen, Li; Nielsen, Maria Overbeck; Qanie, Diyako W.; Kratchmarova, Irina; Kassem, Moustapha; Andersen, Jens S.

2012-01-01

It is well established that bone forming cells (osteoblasts) secrete proteins with autocrine, paracrine, and endocrine function. However, the identity and functional role for the majority of these secreted and differentially expressed proteins during the osteoblast (OB) differentiation process, is not fully established. To address these questions, we quantified the temporal dynamics of the human stromal (mesenchymal, skeletal) stem cell (hMSC) secretome during ex vivo OB differentiation using stable isotope labeling by amino acids in cell culture (SILAC). In addition, we employed pulsed SILAC labeling to distinguish genuine secreted proteins from intracellular contaminants. We identified 466 potentially secreted proteins that were quantified at 5 time-points during 14-days ex vivo OB differentiation including 41 proteins known to be involved in OB functions. Among these, 315 proteins exhibited more than 2-fold up or down-regulation. The pulsed SILAC method revealed a strong correlation between the fraction of isotope labeling and the subset of proteins known to be secreted and involved in OB differentiation. We verified SILAC data using qRT-PCR analysis of 9 identified potential novel regulators of OB differentiation. Furthermore, we studied the biological effects of one of these proteins, the hormone stanniocalcin 2 (STC2) and demonstrated its autocrine effects in enhancing osteoblastic differentiation of hMSC. In conclusion, combining complete and pulsed SILAC labeling facilitated the identification of novel factors produced by hMSC with potential role in OB differentiation. Our study demonstrates that the secretome of osteoblastic cells is more complex than previously reported and supports the emerging evidence that osteoblastic cells secrete proteins with endocrine functions and regulate cellular processes beyond bone formation. PMID:22801418

Comparative Transcriptome Analysis Identifies Candidate Genes Related to Skin Color Differentiation in Red Tilapia.

Science.gov (United States)

Zhu, Wenbin; Wang, Lanmei; Dong, Zaijie; Chen, Xingting; Song, Feibiao; Liu, Nian; Yang, Hui; Fu, Jianjun

2016-08-11

Red tilapia is becoming more popular for aquaculture production in China in recent years. However, the pigmentation differentiation in genetic breeding is the main problem limiting its development of commercial red tilapia culture and the genetic basis of skin color variation is still unknown. In this study, we conducted Illumina sequencing of transcriptome on three color variety red tilapia. A total of 224,895,758 reads were generated, resulting in 160,762 assembled contigs that were used as reference contigs. The contigs of red tilapia transcriptome had hits in the range of 53.4% to 86.7% of the unique proteins of zebrafish, fugu, medaka, three-spined stickleback and tilapia. And 44,723 contigs containing 77,423 simple sequence repeats (SSRs) were identified, with 16,646 contigs containing more than one SSR. Three skin transcriptomes were compared pairwise and the results revealed that there were 148 common significantly differentially expressed unigenes and several key genes related to pigment synthesis, i.e. tyr, tyrp1, silv, sox10, slc24a5, cbs and slc7a11, were included. The results will facilitate understanding the molecular mechanisms of skin pigmentation differentiation in red tilapia and accelerate the molecular selection of the specific strain with consistent skin colors.

The comparability of English, French and Dutch scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F: an assessment of differential item functioning in patients with systemic sclerosis.

Directory of Open Access Journals (Sweden)

Linda Kwakkenbos

Full Text Available The Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F is commonly used to assess fatigue in rheumatic diseases, and has shown to discriminate better across levels of the fatigue spectrum than other commonly used measures. The aim of this study was to assess the cross-language measurement equivalence of the English, French, and Dutch versions of the FACIT-F in systemic sclerosis (SSc patients.The FACIT-F was completed by 871 English-speaking Canadian, 238 French-speaking Canadian and 230 Dutch SSc patients. Confirmatory factor analysis was used to assess the factor structure in the three samples. The Multiple-Indicator Multiple-Cause (MIMIC model was utilized to assess differential item functioning (DIF, comparing English versus French and versus Dutch patient responses separately.A unidimensional factor model showed good fit in all samples. Comparing French versus English patients, statistically significant, but small-magnitude DIF was found for 3 of 13 items. French patients had 0.04 of a standard deviation (SD lower latent fatigue scores than English patients and there was an increase of only 0.03 SD after accounting for DIF. For the Dutch versus English comparison, 4 items showed small, but statistically significant, DIF. Dutch patients had 0.20 SD lower latent fatigue scores than English patients. After correcting for DIF, there was a reduction of 0.16 SD in this difference.There was statistically significant DIF in several items, but the overall effect on fatigue scores was minimal. English, French and Dutch versions of the FACIT-F can be reasonably treated as having equivalent scoring metrics.

New potential markers of in vitro tomato morphogenesis identified by mRNA differential display.

Science.gov (United States)

Torelli, A; Soragni, E; Bolchi, A; Petrucco, S; Ottonello, S; Branca, C

1996-12-01

The identification of plant genes involved in early phases of in vitro morphogenesis can not only contribute to our understanding of the processes underlying growth regulator-controlled determination, but also provide novel markers for evaluating the outcome of in vitro regeneration experiments. To search for such genes and to monitor changes in gene expression accompanying in vitro regeneration, we have adapted the mRNA differential display technique to the comparative analysis of a model system of tomato cotyledons that can be driven selectively toward either shoot or callus formation by means of previously determined growth regulator supplementations. Hormone-independent transcriptional modulation (mainly down-regulation) has been found to be the most common event, indicating that a non-specific reprogramming of gene expression quantitatively predominates during the early phases of in vitro culture. However, cDNA fragments representative of genes that are either down-regulated or induced in a programme-specific manner could also be identified, and two of them (G35, G36) were further characterized. One of these cDNA fragments, G35, corresponds to an mRNA that is down-regulated much earlier in callus- (day 2) than in shoot-determined explants (day 6). The other, G36, identifies an mRNA that is transiently expressed in shoot-determined explants only, well before any macroscopic signs of differentiation become apparent, and thus exhibits typical features of a morphogenetic marker.

The Role of Medial Temporal Lobe Regions in Incidental and Intentional Retrieval of Item and Relational Information in Aging.

Science.gov (United States)

Wang, Wei-Chun; Giovanello, Kelly S

2016-06-01

Considerable neuropsychological and neuroimaging work indicates that the medial temporal lobes are critical for both item and relational memory retrieval. However, there remain outstanding issues in the literature, namely the extent to which medial temporal lobe regions are differentially recruited during incidental and intentional retrieval of item and relational information, and the extent to which aging may affect these neural substrates. The current fMRI study sought to address these questions; participants incidentally encoded word pairs embedded in sentences and incidental item and relational retrieval were assessed through speeded reading of intact, rearranged, and new word-pair sentences, while intentional item and relational retrieval were assessed through old/new associative recognition of a separate set of intact, rearranged, and new word pairs. Results indicated that, in both younger and older adults, anterior hippocampus and perirhinal cortex indexed incidental and intentional item retrieval in the same manner. In contrast, posterior hippocampus supported incidental and intentional relational retrieval in both age groups and an adjacent cluster in posterior hippocampus was recruited during both forms of relational retrieval for older, but not younger, adults. Our findings suggest that while medial temporal lobe regions do not differentiate between incidental and intentional forms of retrieval, there are distinct roles for anterior and posterior medial temporal lobe regions during retrieval of item and relational information, respectively, and further indicate that posterior regions may, under certain conditions, be over-recruited in healthy aging. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

NUNI (New User and New Item) Problem for SRSs Using Content Aware Multimedia-Based Approach

DEFF Research Database (Denmark)

Chaudhary, Pankaj; Deshmukh, Aaradhana A.; Mihovska, Albena Dimitrova

2015-01-01

Recommendation systems suggest items and users of interest based on preferences of items or users and item or user attributes. In social media-based services of dynamic content (such as news, blog, video, movies, books, etc.), recommender systems face the problem of discovering new items, new users...... the problem of identifying the new items and new users, to alleviate the dimensionality of the item-user rating matrix using biclustering technique. To overcome the information exiguity and rating diversity, it uses the smoothing and fusion technique. As discussed, the system presents content aware multimedia...

Development of the Oxford Participation and Activities Questionnaire: constructing an item pool

Directory of Open Access Journals (Sweden)

Kelly L

2015-05-01

Full Text Available Laura Kelly, Crispin Jenkinson, Sarah Dummett, Jill Dawson, Ray Fitzpatrick, David Morley Health Services Research Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK Purpose: The Oxford Participation and Activities Questionnaire is a patient-reported outcome measure in development that is grounded on the World Health Organization International Classification of Functioning, Disability, and Health (ICF. The study reported here aimed to inform and generate an item pool for the new measure, which is specifically designed for the assessment of participation and activity in patients experiencing a range of health conditions. Methods: Items were informed through in-depth interviews conducted with 37 participants spanning a range of conditions. Interviews aimed to identify how their condition impacted their ability to participate in meaningful activities. Conditions included arthritis, cancer, chronic back pain, diabetes, motor neuron disease, multiple sclerosis, Parkinson's disease, and spinal cord injury. Transcripts were analyzed using the framework method. Statements relating to ICF themes were recast as questionnaire items and shown for review to an expert panel. Cognitive debrief interviews (n=13 were used to assess items for face and content validity. Results: ICF themes relevant to activities and participation in everyday life were explored, and a total of 222 items formed the initial item pool. This item pool was refined by the research team and 28 generic items were mapped onto all nine chapters of the ICF construct, detailing activity and participation. Cognitive interviewing confirmed the questionnaire instructions, items, and response options were acceptable to participants. Conclusion: Using a clear conceptual basis to inform item generation, 28 items have been identified as suitable to undergo further psychometric testing. A large-scale postal survey will follow in order to refine the instrument further and

Item response theory scoring and the detection of curvilinear relationships.

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Carter, Nathan T; Dalal, Dev K; Guan, Li; LoPilato, Alexander C; Withrow, Scott A

2017-03-01

Psychologists are increasingly positing theories of behavior that suggest psychological constructs are curvilinearly related to outcomes. However, results from empirical tests for such curvilinear relations have been mixed. We propose that correctly identifying the response process underlying responses to measures is important for the accuracy of these tests. Indeed, past research has indicated that item responses to many self-report measures follow an ideal point response process-wherein respondents agree only to items that reflect their own standing on the measured variable-as opposed to a dominance process, wherein stronger agreement, regardless of item content, is always indicative of higher standing on the construct. We test whether item response theory (IRT) scoring appropriate for the underlying response process to self-report measures results in more accurate tests for curvilinearity. In 2 simulation studies, we show that, regardless of the underlying response process used to generate the data, using the traditional sum-score generally results in high Type 1 error rates or low power for detecting curvilinearity, depending on the distribution of item locations. With few exceptions, appropriate power and Type 1 error rates are achieved when dominance-based and ideal point-based IRT scoring are correctly used to score dominance and ideal point response data, respectively. We conclude that (a) researchers should be theory-guided when hypothesizing and testing for curvilinear relations; (b) correctly identifying whether responses follow an ideal point versus dominance process, particularly when items are not extreme is critical; and (c) IRT model-based scoring is crucial for accurate tests of curvilinearity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

ITEM LEVEL DIAGNOSTICS AND MODEL - DATA FIT IN ITEM ...

African Journals Online (AJOL)

Global Journal

Item response theory (IRT) is a framework for modeling and analyzing item response ... data. Though, there is an argument that the evaluation of fit in IRT modeling has been ... National Council on Measurement in Education ... model data fit should be based on three types of ... prediction should be assessed through the.

78 FR 59968 - Notice of Intent To Repatriate Cultural Items: U.S. Department of the Interior, Bureau of Indian...

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2013-09-30

... Native Hawaiian organizations, have determined that the cultural item listed in this notice meets the... organization not identified in this notice that wish to claim these cultural items should submit a written... Hawaiian organization not identified in this notice that wish to claim these cultural items should submit a...

Selecting informative food items for compiling food-frequency questionnaires: Comparison of procedures

NARCIS (Netherlands)

Molag, M.L.; Vries, J.H.M. de; Duif, N.; Ocké, M.C.; Dagnelie, P.C.; Goldbohm, R.A.; Veer, P. van 't

2010-01-01

The authors automated the selection of foods in a computer system that compiles and processes tailored FFQ. For the selection of food items, several methods are available. The aim of the present study was to compare food lists made by MOM2, which identifies food items with highest between-person

Sensitivity of Equated Aggregate Scores to the Treatment of Misbehaving Common Items

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Michaelides, Michalis P.

2010-01-01

The delta-plot method (Angoff, 1972) is a graphical technique used in the context of test equating for identifying common items with aberrant changes in their item difficulties across administrations or alternate forms. This brief research report explores the effects on equated aggregate scores when delta-plot outliers are either retained in or…

Evolution of a Test Item

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Spaan, Mary

2007-01-01

This article follows the development of test items (see "Language Assessment Quarterly", Volume 3 Issue 1, pp. 71-79 for the article "Test and Item Specifications Development"), beginning with a review of test and item specifications, then proceeding to writing and editing of items, pretesting and analysis, and finally selection of an item for a…

A photographic method to measure food item intake. Validation in geriatric institutions.

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Pouyet, Virginie; Cuvelier, Gérard; Benattar, Linda; Giboreau, Agnès

2015-01-01

From both a clinical and research perspective, measuring food intake is an important issue in geriatric institutions. However, weighing food in this context can be complex, particularly when the items remaining on a plate (side dish, meat or fish and sauce) need to be weighed separately following consumption. A method based on photography that involves taking photographs after a meal to determine food intake consequently seems to be a good alternative. This method enables the storage of raw data so that unhurried analyses can be performed to distinguish the food items present in the images. Therefore, the aim of this paper was to validate a photographic method to measure food intake in terms of differentiating food item intake in the context of a geriatric institution. Sixty-six elderly residents took part in this study, which was performed in four French nursing homes. Four dishes of standardized portions were offered to the residents during 16 different lunchtimes. Three non-trained assessors then independently estimated both the total and specific food item intakes of the participants using images of their plates taken after the meal (photographic method) and a reference image of one plate taken before the meal. Total food intakes were also recorded by weighing the food. To test the reliability of the photographic method, agreements between different assessors and agreements among various estimates made by the same assessor were evaluated. To test the accuracy and specificity of this method, food intake estimates for the four dishes were compared with the food intakes determined using the weighed food method. To illustrate the added value of the photographic method, food consumption differences between the dishes were explained by investigating the intakes of specific food items. Although they were not specifically trained for this purpose, the results demonstrated that the assessor estimates agreed between assessors and among various estimates made by the same

The Longer We Have to Forget the More We Remember: The Ironic Effect of Postcue Duration in Item-Based Directed Forgetting

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Bancroft, Tyler D.; Hockley, William E.; Farquhar, Riley

2013-01-01

The effects of the duration of remember and forget cues were examined to test the differential rehearsal account of item-based directed forgetting. In Experiments 1 and 2, cues were shown for 300, 600, or 900 ms, and a directed forgetting effect (better recognition of remember than forget items) was found at each duration. In addition, recognition…

Psychometric validation of the Persian nine-item Internet Gaming Disorder Scale - Short Form: Does gender and hours spent online gaming affect the interpretations of item descriptions?

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Wu, Tzu-Yi; Lin, Chung-Ying; Årestedt, Kristofer; Griffiths, Mark D; Broström, Anders; Pakpour, Amir H

2017-06-01

Background and aims The nine-item Internet Gaming Disorder Scale - Short Form (IGDS-SF9) is brief and effective to evaluate Internet Gaming Disorder (IGD) severity. Although its scores show promising psychometric properties, less is known about whether different groups of gamers interpret the items similarly. This study aimed to verify the construct validity of the Persian IGDS-SF9 and examine the scores in relation to gender and hours spent online gaming among 2,363 Iranian adolescents. Methods Confirmatory factor analysis (CFA) and Rasch analysis were used to examine the construct validity of the IGDS-SF9. The effects of gender and time spent online gaming per week were investigated by multigroup CFA and Rasch differential item functioning (DIF). Results The unidimensionality of the IGDS-SF9 was supported in both CFA and Rasch. However, Item 4 (fail to control or cease gaming activities) displayed DIF (DIF contrast = 0.55) slightly over the recommended cutoff in Rasch but was invariant in multigroup CFA across gender. Items 4 (DIF contrast = -0.67) and 9 (jeopardize or lose an important thing because of gaming activity; DIF contrast = 0.61) displayed DIF in Rasch and were non-invariant in multigroup CFA across time spent online gaming. Conclusions Given the Persian IGDS-SF9 was unidimensional, it is concluded that the instrument can be used to assess IGD severity. However, users of the instrument are cautioned concerning the comparisons of the sum scores of the IGDS-SF9 across gender and across adolescents spending different amounts of time online gaming.

The Comparability of English, French and Dutch Scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F): An Assessment of Differential Item Functioning in Patients with Systemic Sclerosis

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Kwakkenbos, Linda; Willems, Linda M.; Baron, Murray; Hudson, Marie; Cella, David; van den Ende, Cornelia H. M.; Thombs, Brett D.

2014-01-01

Objective The Functional Assessment of Chronic Illness Therapy- Fatigue (FACIT-F) is commonly used to assess fatigue in rheumatic diseases, and has shown to discriminate better across levels of the fatigue spectrum than other commonly used measures. The aim of this study was to assess the cross-language measurement equivalence of the English, French, and Dutch versions of the FACIT-F in systemic sclerosis (SSc) patients. Methods The FACIT-F was completed by 871 English-speaking Canadian, 238 French-speaking Canadian and 230 Dutch SSc patients. Confirmatory factor analysis was used to assess the factor structure in the three samples. The Multiple-Indicator Multiple-Cause (MIMIC) model was utilized to assess differential item functioning (DIF), comparing English versus French and versus Dutch patient responses separately. Results A unidimensional factor model showed good fit in all samples. Comparing French versus English patients, statistically significant, but small-magnitude DIF was found for 3 of 13 items. French patients had 0.04 of a standard deviation (SD) lower latent fatigue scores than English patients and there was an increase of only 0.03 SD after accounting for DIF. For the Dutch versus English comparison, 4 items showed small, but statistically significant, DIF. Dutch patients had 0.20 SD lower latent fatigue scores than English patients. After correcting for DIF, there was a reduction of 0.16 SD in this difference. Conclusions There was statistically significant DIF in several items, but the overall effect on fatigue scores was minimal. English, French and Dutch versions of the FACIT-F can be reasonably treated as having equivalent scoring metrics. PMID:24638101

Improving Measurement Efficiency of the Inner EAR Scale with Item Response Theory.

Science.gov (United States)

Jessen, Annika; Ho, Andrew D; Corrales, C Eduardo; Yueh, Bevan; Shin, Jennifer J

2018-02-01

Objectives (1) To assess the 11-item Inner Effectiveness of Auditory Rehabilitation (Inner EAR) instrument with item response theory (IRT). (2) To determine whether the underlying latent ability could also be accurately represented by a subset of the items for use in high-volume clinical scenarios. (3) To determine whether the Inner EAR instrument correlates with pure tone thresholds and word recognition scores. Design IRT evaluation of prospective cohort data. Setting Tertiary care academic ambulatory otolaryngology clinic. Subjects and Methods Modern psychometric methods, including factor analysis and IRT, were used to assess unidimensionality and item properties. Regression methods were used to assess prediction of word recognition and pure tone audiometry scores. Results The Inner EAR scale is unidimensional, and items varied in their location and information. Information parameter estimates ranged from 1.63 to 4.52, with higher values indicating more useful items. The IRT model provided a basis for identifying 2 sets of items with relatively lower information parameters. Item information functions demonstrated which items added insubstantial value over and above other items and were removed in stages, creating a 8- and 3-item Inner EAR scale for more efficient assessment. The 8-item version accurately reflected the underlying construct. All versions correlated moderately with word recognition scores and pure tone averages. Conclusion The 11-, 8-, and 3-item versions of the Inner EAR scale have strong psychometric properties, and there is correlational validity evidence for the observed scores. Modern psychometric methods can help streamline care delivery by maximizing relevant information per item administered.

Why are the Mathematics National Examination Items Difficult and What Is Teachers’ Strategy to Overcome It?

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Heri Retnawati

2017-07-01

Full Text Available The quality of national examination items plays an enormous role in identifying students’ competencies mastery and their difficulties. This study aims to identify the difficult items in the Junior High School Mathematics National Examination, to find the factors that cause students’ difficulty and to reveal the strategies that the teachers and the students might implement in order to overcome them. The study is phenomenological research with the mixed methods. The data were collected using documentation of students’ responses and focus group discussion (FGD of teachers. The data analysis was conducted using Milles & Hubberman steps. The results of the study showed that there were 4 difficult items of the 40 test items for the students. The students’ difficulties were the lack of concept understanding, difficulties in calculating, difficulties in selecting information, being deceived by the distractors, being unaccustomed to completing complex and non-integers test items, and completing contextual test items that have been presented in the form of figures or narrative texts.

The Piper Fatigue Scale-12 (PFS-12): psychometric findings and item reduction in a cohort of breast cancer survivors.

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Reeve, Bryce B; Stover, Angela M; Alfano, Catherine M; Smith, Ashley Wilder; Ballard-Barbash, Rachel; Bernstein, Leslie; McTiernan, Anne; Baumgartner, Kathy B; Piper, Barbara F

2012-11-01

Brief, valid measures of fatigue, a prevalent and distressing cancer symptom, are needed for use in research. This study's primary aim was to create a shortened version of the revised Piper Fatigue Scale (PFS-R) based on data from a diverse cohort of breast cancer survivors. A secondary aim was to determine whether the PFS captured multiple distinct aspects of fatigue (a multidimensional model) or a single overall fatigue factor (a unidimensional model). Breast cancer survivors (n = 799; stages in situ through IIIa; ages 29-86 years) were recruited through three SEER registries (New Mexico, Western Washington, and Los Angeles, CA) as part of the Health, Eating, Activity, and Lifestyle (HEAL) study. Fatigue was measured approximately 3 years post-diagnosis using the 22-item PFS-R that has four subscales (Behavior, Affect, Sensory, and Cognition). Confirmatory factor analysis was used to compare unidimensional and multidimensional models. Six criteria were used to make item selections to shorten the PFS-R: scale's content validity, items' relationship with fatigue, content redundancy, differential item functioning by race and/or education, scale reliability, and literacy demand. Factor analyses supported the original 4-factor structure. There was also evidence from the bi-factor model for a dominant underlying fatigue factor. Six items tested positive for differential item functioning between African-American and Caucasian survivors. Four additional items either showed poor association, local dependence, or content validity concerns. After removing these 10 items, the reliability of the PFS-12 subscales ranged from 0.87 to 0.89, compared to 0.90-0.94 prior to item removal. The newly developed PFS-12 can be used to assess fatigue in African-American and Caucasian breast cancer survivors and reduces response burden without compromising reliability or validity. This is the first study to determine PFS literacy demand and to compare PFS-R responses in African

Assessing Psychopathy Among Justice Involved Adolescents with the PCL: YV: An Item Response Theory Examination Across Gender

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Tsang, Siny; Schmidt, Karen M.; Vincent, Gina M.; Salekin, Randall T.; Moretti, Marlene M.; Odgers, Candice L.

2014-01-01

This study used an item response theory (IRT) model and a large adolescent sample of justice involved youth (N = 1,007, 38% female) to examine the item functioning of the Psychopathy Checklist – Youth Version (PCL: YV). Items that were most discriminating (or most sensitive to changes) of the latent trait (thought to be psychopathy) among adolescents included “Glibness/superficial charm”, “Lack of remorse”, and “Need for stimulation”, whereas items that were least discriminating included “Pathological lying”, “Failure to accept responsibility”, and “Lacks goals.” The items “Impulsivity” and “Irresponsibility” were the most likely to be rated high among adolescents, whereas “Parasitic lifestyle”, and “Glibness/superficial charm” were the most likely to be rated low. Evidence of differential item functioning (DIF) on four of the 13 items was found between boys and girls. “Failure to accept responsibility” and “Impulsivity” were endorsed more frequently to describe adolescent girls than boys at similar levels of the latent trait, and vice versa for “Grandiose sense of self-worth” and “Lacks goals.” The DIF findings suggest that four PCL: YV items function differently between boys and girls. PMID:25580672

Instructional Topics in Educational Measurement (ITEMS) Module: Using Automated Processes to Generate Test Items

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Gierl, Mark J.; Lai, Hollis

2013-01-01

Changes to the design and development of our educational assessments are resulting in the unprecedented demand for a large and continuous supply of content-specific test items. One way to address this growing demand is with automatic item generation (AIG). AIG is the process of using item models to generate test items with the aid of computer…

Teoria da Resposta ao Item Teoria de la respuesta al item Item response theory

Directory of Open Access Journals (Sweden)

Eutalia Aparecida Candido de Araujo

2009-12-01

Full Text Available A preocupação com medidas de traços psicológicos é antiga, sendo que muitos estudos e propostas de métodos foram desenvolvidos no sentido de alcançar este objetivo. Entre os trabalhos propostos, destaca-se a Teoria da Resposta ao Item (TRI que, a princípio, veio completar limitações da Teoria Clássica de Medidas, empregada em larga escala até hoje na medida de traços psicológicos. O ponto principal da TRI é que ela leva em consideração o item particularmente, sem relevar os escores totais; portanto, as conclusões não dependem apenas do teste ou questionário, mas de cada item que o compõe. Este artigo propõe-se a apresentar esta Teoria que revolucionou a teoria de medidas.La preocupación con las medidas de los rasgos psicológicos es antigua y muchos estudios y propuestas de métodos fueron desarrollados para lograr este objetivo. Entre estas propuestas de trabajo se incluye la Teoría de la Respuesta al Ítem (TRI que, en principio, vino a completar las limitaciones de la Teoría Clásica de los Tests, ampliamente utilizada hasta hoy en la medida de los rasgos psicológicos. El punto principal de la TRI es que se tiene en cuenta el punto concreto, sin relevar las puntuaciones totales; por lo tanto, los resultados no sólo dependen de la prueba o cuestionario, sino que de cada ítem que lo compone. En este artículo se propone presentar la Teoría que revolucionó la teoría de medidas.The concern with measures of psychological traits is old and many studies and proposals of methods were developed to achieve this goal. Among these proposed methods highlights the Item Response Theory (IRT that, in principle, came to complete limitations of the Classical Test Theory, which is widely used until nowadays in the measurement of psychological traits. The main point of IRT is that it takes into account the item in particular, not relieving the total scores; therefore, the findings do not only depend on the test or questionnaire

Web items recommendation using hybridized content-based and ...

African Journals Online (AJOL)

Recommender Systems are software agent developed to tackle the problem of information overload by providing recommendations that assist individual users identify contents of interest by using the opinions of a community of users, similarities between items contents or the user's preferences. The exponential growth of ...

Measuring psychological trauma after spinal cord injury: Development and psychometric characteristics of the SCI-QOL Psychological Trauma item bank and short form.

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Kisala, Pamela A; Victorson, David; Pace, Natalie; Heinemann, Allen W; Choi, Seung W; Tulsky, David S

2015-05-01

To describe the development and psychometric properties of the SCI-QOL Psychological Trauma item bank and short form. Using a mixed-methods design, we developed and tested a Psychological Trauma item bank with patient and provider focus groups, cognitive interviews, and item response theory based analytic approaches, including tests of model fit, differential item functioning (DIF) and precision. We tested a 31-item pool at several medical institutions across the United States, including the University of Michigan, Kessler Foundation, Rehabilitation Institute of Chicago, the University of Washington, Craig Hospital and the James J. Peters/Bronx Veterans Administration hospital. A total of 716 individuals with SCI completed the trauma items The 31 items fit a unidimensional model (CFI=0.952; RMSEA=0.061) and demonstrated good precision (theta range between 0.6 and 2.5). Nine items demonstrated negligible DIF with little impact on score estimates. The final calibrated item bank contains 19 items The SCI-QOL Psychological Trauma item bank is a psychometrically robust measurement tool from which a short form and a computer adaptive test (CAT) version are available.

Computerized Adaptive Test (CAT) Applications and Item Response Theory Models for Polytomous Items

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Aybek, Eren Can; Demirtasli, R. Nukhet

2017-01-01

This article aims to provide a theoretical framework for computerized adaptive tests (CAT) and item response theory models for polytomous items. Besides that, it aims to introduce the simulation and live CAT software to the related researchers. Computerized adaptive test algorithm, assumptions of item response theory models, nominal response…

A Differential Item Functioning (DIF) Analysis of the Communicative Participation Item Bank (CPIB): Comparing Individuals with Parkinson's Disease from the United States and New Zealand

Science.gov (United States)

Baylor, Carolyn; McAuliffe, Megan J.; Hughes, Louise E.; Yorkston, Kathryn; Anderson, Tim; Jiseon, Kim; Amtmann, Dagmar

2014-01-01

Purpose: To examine the cross-cultural applicability of the Communicative Participation Item Bank (CPIB) through a comparison of respondents with Parkinson's disease (PD) from the United States and New Zealand. Method: A total of 428 respondents--218 from the United States and 210 from New Zealand-completed the self-report CPIB and a series of…

Evaluation of the Multiple Sclerosis Walking Scale-12 (MSWS-12) in a Dutch sample: Application of item response theory.

Science.gov (United States)

Mokkink, Lidwine Brigitta; Galindo-Garre, Francisca; Uitdehaag, Bernard Mj

2016-12-01

The Multiple Sclerosis Walking Scale-12 (MSWS-12) measures walking ability from the patients' perspective. We examined the quality of the MSWS-12 using an item response theory model, the graded response model (GRM). A total of 625 unique Dutch multiple sclerosis (MS) patients were included. After testing for unidimensionality, monotonicity, and absence of local dependence, a GRM was fit and item characteristics were assessed. Differential item functioning (DIF) for the variables gender, age, duration of MS, type of MS and severity of MS, reliability, total test information, and standard error of the trait level (θ) were investigated. Confirmatory factor analysis showed a unidimensional structure of the 12 items of the scale, explaining 88% of the variance. Item 2 did not fit into the GRM model. Reliability was 0.93. Items 8 and 9 (of the 11 and 12 item version respectively) showed DIF on the variable severity, based on the Expanded Disability Status Scale (EDSS). However, the EDSS is strongly related to the content of both items. Our results confirm the good quality of the MSWS-12. The trait level (θ) scores and item parameters of both the 12- and 11-item versions were highly comparable, although we do not suggest to change the content of the MSWS-12. © The Author(s), 2016.

Selecting Items for Criterion-Referenced Tests.

Science.gov (United States)

Mellenbergh, Gideon J.; van der Linden, Wim J.

1982-01-01

Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)

Asymptotic Standard Errors for Item Response Theory True Score Equating of Polytomous Items

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Cher Wong, Cheow

2015-01-01

Building on previous works by Lord and Ogasawara for dichotomous items, this article proposes an approach to derive the asymptotic standard errors of item response theory true score equating involving polytomous items, for equivalent and nonequivalent groups of examinees. This analytical approach could be used in place of empirical methods like…

Answering Fixed Response Items in Chemistry: A Pilot Study.

Science.gov (United States)

Hateley, R. J.

1979-01-01

Presents a pilot study on student thinking in chemistry. Verbal comments of a group of six college students were recorded and analyzed to identify how each student arrives at the correct answer in fixed response items in chemisty. (HM)

78 FR 50107 - Notice of Intent To Repatriate Cultural Items: University of Colorado Museum of Natural History...

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2013-08-16

... organizations, has determined that the cultural items listed in this notice meet the definition of sacred... Native Hawaiian organization not identified in this notice that wish to claim these cultural items should... tribe or Native Hawaiian organization not identified in this notice that wish to claim these cultural...

The Dutch-Flemish PROMIS Physical Function item bank exhibited strong psychometric properties in patients with chronic pain.

Science.gov (United States)

Crins, Martine H P; Terwee, Caroline B; Klausch, Thomas; Smits, Niels; de Vet, Henrica C W; Westhovens, Rene; Cella, David; Cook, Karon F; Revicki, Dennis A; van Leeuwen, Jaap; Boers, Maarten; Dekker, Joost; Roorda, Leo D

2017-07-01

The objective of this study was to assess the psychometric properties of the Dutch-Flemish Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function item bank in Dutch patients with chronic pain. A bank of 121 items was administered to 1,247 Dutch patients with chronic pain. Unidimensionality was assessed by fitting a one-factor confirmatory factor analysis and evaluating resulting fit statistics. Items were calibrated with the graded response model and its fit was evaluated. Cross-cultural validity was assessed by testing items for differential item functioning (DIF) based on language (Dutch vs. English). Construct validity was evaluated by calculation correlations between scores on the Dutch-Flemish PROMIS Physical Function measure and scores on generic and disease-specific measures. Results supported the Dutch-Flemish PROMIS Physical Function item bank's unidimensionality (Comparative Fit Index = 0.976, Tucker Lewis Index = 0.976) and model fit. Item thresholds targeted a wide range of physical function construct (threshold-parameters range: -4.2 to 5.6). Cross-cultural validity was good as four items only showed DIF for language and their impact on item scores was minimal. Physical Function scores were strongly associated with scores on all other measures (all correlations ≤ -0.60 as expected). The Dutch-Flemish PROMIS Physical Function item bank exhibited good psychometric properties. Development of a computer adaptive test based on the large bank is warranted. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of Northwest University, Kano Post-UTME Test Items Using Item Response Theory

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Bichi, Ado Abdu; Hafiz, Hadiza; Bello, Samira Abdullahi

2016-01-01

High-stakes testing is used for the purposes of providing results that have important consequences. Validity is the cornerstone upon which all measurement systems are built. This study applied the Item Response Theory principles to analyse Northwest University Kano Post-UTME Economics test items. The developed fifty (50) economics test items was…

Two items remembered as precisely as one: how integral features can improve visual working memory.

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Bae, Gi Yeul; Flombaum, Jonathan I

2013-10-01

In the ongoing debate about the efficacy of visual working memory for more than three items, a consensus has emerged that memory precision declines as memory load increases from one to three. Many studies have reported that memory precision seems to be worse for two items than for one. We argue that memory for two items appears less precise than that for one only because two items present observers with a correspondence challenge that does not arise when only one item is stored--the need to relate observations to their corresponding memory representations. In three experiments, we prevented correspondence errors in two-item trials by varying sample items along task-irrelevant but integral (as opposed to separable) dimensions. (Initial experiments with a classic sorting paradigm identified integral feature relationships.) In three memory experiments, our manipulation produced equally precise representations of two items and of one item.

Calibration and Validation of the Dutch-Flemish PROMIS Pain Interference Item Bank in Patients with Chronic Pain.

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Crins, Martine H P; Roorda, Leo D; Smits, Niels; de Vet, Henrica C W; Westhovens, Rene; Cella, David; Cook, Karon F; Revicki, Dennis; van Leeuwen, Jaap; Boers, Maarten; Dekker, Joost; Terwee, Caroline B

2015-01-01

The Dutch-Flemish PROMIS Group translated the adult PROMIS Pain Interference item bank into Dutch-Flemish. The aims of the current study were to calibrate the parameters of these items using an item response theory (IRT) model, to evaluate the cross-cultural validity of the Dutch-Flemish translations compared to the original English items, and to evaluate their reliability and construct validity. The 40 items in the bank were completed by 1085 Dutch chronic pain patients. Before calibrating the items, IRT model assumptions were evaluated using confirmatory factor analysis (CFA). Items were calibrated using the graded response model (GRM), an IRT model appropriate for items with more than two response options. To evaluate cross-cultural validity, differential item functioning (DIF) for language (Dutch vs. English) was examined. Reliability was evaluated based on standard errors and Cronbach's alpha. To evaluate construct validity correlations with scores on legacy instruments (e.g., the Disabilities of the Arm, Shoulder and Hand Questionnaire) were calculated. Unidimensionality of the Dutch-Flemish PROMIS Pain Interference item bank was supported by CFA tests of model fit (CFI = 0.986, TLI = 0.986). Furthermore, the data fit the GRM and showed good coverage across the pain interference continuum (threshold-parameters range: -3.04 to 3.44). The Dutch-Flemish PROMIS Pain Interference item bank has good cross-cultural validity (only two out of 40 items showing DIF), good reliability (Cronbach's alpha = 0.98), and good construct validity (Pearson correlations between 0.62 and 0.75). A computer adaptive test (CAT) and Dutch-Flemish PROMIS short forms of the Dutch-Flemish PROMIS Pain Interference item bank can now be developed.

Calibration and Validation of the Dutch-Flemish PROMIS Pain Interference Item Bank in Patients with Chronic Pain.

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Martine H P Crins

Full Text Available The Dutch-Flemish PROMIS Group translated the adult PROMIS Pain Interference item bank into Dutch-Flemish. The aims of the current study were to calibrate the parameters of these items using an item response theory (IRT model, to evaluate the cross-cultural validity of the Dutch-Flemish translations compared to the original English items, and to evaluate their reliability and construct validity. The 40 items in the bank were completed by 1085 Dutch chronic pain patients. Before calibrating the items, IRT model assumptions were evaluated using confirmatory factor analysis (CFA. Items were calibrated using the graded response model (GRM, an IRT model appropriate for items with more than two response options. To evaluate cross-cultural validity, differential item functioning (DIF for language (Dutch vs. English was examined. Reliability was evaluated based on standard errors and Cronbach's alpha. To evaluate construct validity correlations with scores on legacy instruments (e.g., the Disabilities of the Arm, Shoulder and Hand Questionnaire were calculated. Unidimensionality of the Dutch-Flemish PROMIS Pain Interference item bank was supported by CFA tests of model fit (CFI = 0.986, TLI = 0.986. Furthermore, the data fit the GRM and showed good coverage across the pain interference continuum (threshold-parameters range: -3.04 to 3.44. The Dutch-Flemish PROMIS Pain Interference item bank has good cross-cultural validity (only two out of 40 items showing DIF, good reliability (Cronbach's alpha = 0.98, and good construct validity (Pearson correlations between 0.62 and 0.75. A computer adaptive test (CAT and Dutch-Flemish PROMIS short forms of the Dutch-Flemish PROMIS Pain Interference item bank can now be developed.

Item Response Data Analysis Using Stata Item Response Theory Package

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Yang, Ji Seung; Zheng, Xiaying

2018-01-01

The purpose of this article is to introduce and review the capability and performance of the Stata item response theory (IRT) package that is available from Stata v.14, 2015. Using a simulated data set and a publicly available item response data set extracted from Programme of International Student Assessment, we review the IRT package from…

Item Banking with Embedded Standards

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MacCann, Robert G.; Stanley, Gordon

2009-01-01

An item banking method that does not use Item Response Theory (IRT) is described. This method provides a comparable grading system across schools that would be suitable for low-stakes testing. It uses the Angoff standard-setting method to obtain item ratings that are stored with each item. An example of such a grading system is given, showing how…

A Non-Parametric Item Response Theory Evaluation of the CAGE Instrument Among Older Adults.

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Abdin, Edimansyah; Sagayadevan, Vathsala; Vaingankar, Janhavi Ajit; Picco, Louisa; Chong, Siow Ann; Subramaniam, Mythily

2018-02-23

The validity of the CAGE using item response theory (IRT) has not yet been examined in older adult population. This study aims to investigate the psychometric properties of the CAGE using both non-parametric and parametric IRT models, assess whether there is any differential item functioning (DIF) by age, gender and ethnicity and examine the measurement precision at the cut-off scores. We used data from the Well-being of the Singapore Elderly study to conduct Mokken scaling analysis (MSA), dichotomous Rasch and 2-parameter logistic IRT models. The measurement precision at the cut-off scores were evaluated using classification accuracy (CA) and classification consistency (CC). The MSA showed the overall scalability H index was 0.459, indicating a medium performing instrument. All items were found to be homogenous, measuring the same construct and able to discriminate well between respondents with high levels of the construct and the ones with lower levels. The item discrimination ranged from 1.07 to 6.73 while the item difficulty ranged from 0.33 to 2.80. Significant DIF was found for 2-item across ethnic group. More than 90% (CC and CA ranged from 92.5% to 94.3%) of the respondents were consistently and accurately classified by the CAGE cut-off scores of 2 and 3. The current study provides new evidence on the validity of the CAGE from the IRT perspective. This study provides valuable information of each item in the assessment of the overall severity of alcohol problem and the precision of the cut-off scores in older adult population.

Comparative gene expression profiling of in vitro differentiated megakaryocytes and erythroblasts identifies novel activatory and inhibitory platelet membrane proteins

NARCIS (Netherlands)

Macaulay, Iain C.; Tijssen, Marloes R.; Thijssen-Timmer, Daphne C.; Gusnanto, Arief; Steward, Michael; Burns, Philippa; Langford, Cordelia F.; Ellis, Peter D.; Dudbridge, Frank; Zwaginga, Jaap-Jan; Watkins, Nicholas A.; van der Schoot, C. Ellen; Ouwehand, Willem H.

2007-01-01

To identify previously unknown platelet receptors we compared the transcriptomes of in vitro differentiated megakaryocytes (MKs) and erythroblasts (EBs). RNA was obtained from purified, biologically paired MK and EB cultures and compared using cDNA microarrays. Bioinformatical analysis of

A high-throughput screen for inhibitors of the prolyl isomerase, Pin1, identifies a seaweed polyphenol that reduces adipose cell differentiation.

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Mori, Tadashi; Hidaka, Masafumi; Ikuji, Hiroko; Yoshizawa, Ibuki; Toyohara, Haruhiko; Okuda, Toru; Uchida, Chiyoko; Asano, Tomoichiro; Yotsu-Yamashita, Mari; Uchida, Takafumi

2014-01-01

The peptidyl prolyl cis/trans isomerase Pin1 enhances the uptake of triglycerides and the differentiation of fibroblasts into adipose cells in response to insulin stimulation. Pin1 downregulation could be a potential approach to prevent and treat obesity-related disorders. In order to identify an inhibitor of Pin1 that exhibited minimal cytotoxicity, we established a high-throughput screen for Pin1 inhibitors and used this method to identify an inhibitor from 1,056 crude fractions of two natural product libraries. The candidate, a phlorotannin called 974-B, was isolated from the seaweed, Ecklonia kurome. 974-B inhibited the differentiation of mouse embryonic fibroblasts and 3T3-L1 cells into adipose cells without inducing cytotoxicity. We discovered the Pin1 inhibitor, 974-B, from the seaweed, E. kurome, and showed that it blocks the differentiation of fibroblasts into adipose cells, suggesting that 974-B could be a lead drug candidate for obesity-related disorders.

P2-19: The Effect of item Repetition on Item-Context Association Depends on the Prior Exposure of Items

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Hongmi Lee

2012-10-01

Full Text Available Previous studies have reported conflicting findings on whether item repetition has beneficial or detrimental effects on source memory. To reconcile such contradictions, we investigated whether the degree of pre-exposure of items can be a potential modulating factor. The experimental procedures spanned two consecutive days. On Day 1, participants were exposed to a set of unfamiliar faces. On Day 2, the same faces presented on the previous day were used again in half of the participants, whereas novel faces were used for the other half. Day 2 procedures consisted of three successive phases: item repetition, source association, and source memory test. In the item repetition phase, half of the face stimuli were repeatedly presented while participants were making male/female judgments. During the source association phase, both the repeated and the unrepeated faces appeared in one of the four locations on the screen. Finally, participants were tested on the location in which a given face was presented during the previous phase and reported the confidence of their memory. Source memory accuracy was measured as the percentage of correct non-guess trials. As results, we found a significant interaction between prior exposure and repetition. Repetition impaired source memory when the items had been pre-exposed on Day 1, while it led to greater accuracy in novel ones. These results show that pre-experimental exposure can modulate the effects of repetition on associative binding between an item and its contextual information, suggesting that pre-existing representation and novelty signal interact to form new episodic memory.

Optimization approach of background value and initial item for improving prediction precision of GM(1,1) model

Institute of Scientific and Technical Information of China (English)

Yuhong Wang; Qin Liu; Jianrong Tang; Wenbin Cao; Xiaozhong Li

2014-01-01

A combination method of optimization of the back-ground value and optimization of the initial item is proposed. The sequences of the unbiased exponential distribution are simulated and predicted through the optimization of the background value in grey differential equations. The principle of the new information priority in the grey system theory and the rationality of the initial item in the original GM(1,1) model are ful y expressed through the improvement of the initial item in the proposed time response function. A numerical example is employed to il ustrate that the proposed method is able to simulate and predict sequences of raw data with the unbiased exponential distribution and has better simulation performance and prediction precision than the original GM(1,1) model relatively.

HIV/AIDS knowledge among men who have sex with men: applying the item response theory.

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Gomes, Raquel Regina de Freitas Magalhães; Batista, José Rodrigues; Ceccato, Maria das Graças Braga; Kerr, Lígia Regina Franco Sansigolo; Guimarães, Mark Drew Crosland

2014-04-01

To evaluate the level of HIV/AIDS knowledge among men who have sex with men in Brazil using the latent trait model estimated by Item Response Theory. Multicenter, cross-sectional study, carried out in ten Brazilian cities between 2008 and 2009. Adult men who have sex with men were recruited (n = 3,746) through Respondent Driven Sampling. HIV/AIDS knowledge was ascertained through ten statements by face-to-face interview and latent scores were obtained through two-parameter logistic modeling (difficulty and discrimination) using Item Response Theory. Differential item functioning was used to examine each item characteristic curve by age and schooling. Overall, the HIV/AIDS knowledge scores using Item Response Theory did not exceed 6.0 (scale 0-10), with mean and median values of 5.0 (SD = 0.9) and 5.3, respectively, with 40.7% of the sample with knowledge levels below the average. Some beliefs still exist in this population regarding the transmission of the virus by insect bites, by using public restrooms, and by sharing utensils during meals. With regard to the difficulty and discrimination parameters, eight items were located below the mean of the scale and were considered very easy, and four items presented very low discrimination parameter (items contributed to the inaccuracy of the measurement of knowledge among those with median level and above. Item Response Theory analysis, which focuses on the individual properties of each item, allows measures to be obtained that do not vary or depend on the questionnaire, which provides better ascertainment and accuracy of knowledge scores. Valid and reliable scales are essential for monitoring HIV/AIDS knowledge among the men who have sex with men population over time and in different geographic regions, and this psychometric model brings this advantage.

Assessing normative cut points through differential item functioning analysis: an example from the adaptation of the Middlesex Elderly Assessment of Mental State (MEAMS) for use as a cognitive screening test in Turkey.

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Tennant, Alan; Küçükdeveci, Ayse A; Kutlay, Sehim; Elhan, Atilla H

2006-03-23

The Middlesex Elderly Assessment of Mental State (MEAMS) was developed as a screening test to detect cognitive impairment in the elderly. It includes 12 subtests, each having a 'pass score'. A series of tasks were undertaken to adapt the measure for use in the adult population in Turkey and to determine the validity of existing cut points for passing subtests, given the wide range of educational level in the Turkish population. This study focuses on identifying and validating the scoring system of the MEAMS for Turkish adult population. After the translation procedure, 350 normal subjects and 158 acquired brain injury patients were assessed by the Turkish version of MEAMS. Initially, appropriate pass scores for the normal population were determined through ANOVA post-hoc tests according to age, gender and education. Rasch analysis was then used to test the internal construct validity of the scale and the validity of the cut points for pass scores on the pooled data by using Differential Item Functioning (DIF) analysis within the framework of the Rasch model. Data with the initially modified pass scores were analyzed. DIF was found for certain subtests by age and education, but not for gender. Following this, pass scores were further adjusted and data re-fitted to the model. All subtests were found to fit the Rasch model (mean item fit 0.184, SD 0.319; person fit -0.224, SD 0.557) and DIF was then found to be absent. Thus the final pass scores for all subtests were determined. The MEAMS offers a valid assessment of cognitive state for the adult Turkish population, and the revised cut points accommodate for age and education. Further studies are required to ascertain the validity in different diagnostic groups.

Assessing normative cut points through differential item functioning analysis: An example from the adaptation of the Middlesex Elderly Assessment of Mental State (MEAMS for use as a cognitive screening test in Turkey

Directory of Open Access Journals (Sweden)

Kutlay Sehim

2006-03-01

Full Text Available Abstract Background The Middlesex Elderly Assessment of Mental State (MEAMS was developed as a screening test to detect cognitive impairment in the elderly. It includes 12 subtests, each having a 'pass score'. A series of tasks were undertaken to adapt the measure for use in the adult population in Turkey and to determine the validity of existing cut points for passing subtests, given the wide range of educational level in the Turkish population. This study focuses on identifying and validating the scoring system of the MEAMS for Turkish adult population. Methods After the translation procedure, 350 normal subjects and 158 acquired brain injury patients were assessed by the Turkish version of MEAMS. Initially, appropriate pass scores for the normal population were determined through ANOVA post-hoc tests according to age, gender and education. Rasch analysis was then used to test the internal construct validity of the scale and the validity of the cut points for pass scores on the pooled data by using Differential Item Functioning (DIF analysis within the framework of the Rasch model. Results Data with the initially modified pass scores were analyzed. DIF was found for certain subtests by age and education, but not for gender. Following this, pass scores were further adjusted and data re-fitted to the model. All subtests were found to fit the Rasch model (mean item fit 0.184, SD 0.319; person fit -0.224, SD 0.557 and DIF was then found to be absent. Thus the final pass scores for all subtests were determined. Conclusion The MEAMS offers a valid assessment of cognitive state for the adult Turkish population, and the revised cut points accommodate for age and education. Further studies are required to ascertain the validity in different diagnostic groups.

Cloud-based solution to identify statistically significant MS peaks differentiating sample categories.

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Ji, Jun; Ling, Jeffrey; Jiang, Helen; Wen, Qiaojun; Whitin, John C; Tian, Lu; Cohen, Harvey J; Ling, Xuefeng B

2013-03-23

Mass spectrometry (MS) has evolved to become the primary high throughput tool for proteomics based biomarker discovery. Until now, multiple challenges in protein MS data analysis remain: large-scale and complex data set management; MS peak identification, indexing; and high dimensional peak differential analysis with the concurrent statistical tests based false discovery rate (FDR). "Turnkey" solutions are needed for biomarker investigations to rapidly process MS data sets to identify statistically significant peaks for subsequent validation. Here we present an efficient and effective solution, which provides experimental biologists easy access to "cloud" computing capabilities to analyze MS data. The web portal can be accessed at http://transmed.stanford.edu/ssa/. Presented web application supplies large scale MS data online uploading and analysis with a simple user interface. This bioinformatic tool will facilitate the discovery of the potential protein biomarkers using MS.

Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions

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Yoon Soo ePark

2016-02-01

Full Text Available This study investigates the impact of item parameter drift (IPD on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effect on item parameters and examinee ability.

Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions.

Science.gov (United States)

Park, Yoon Soo; Lee, Young-Sun; Xing, Kuan

2016-01-01

This study investigates the impact of item parameter drift (IPD) on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT) models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS) were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results also showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effects on item parameters and examinee ability.

Identifying differential miR and gene consensus patterns in peripheral blood of patients with cardiovascular diseases from literature data.

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Šatrauskienė, Agnė; Navickas, Rokas; Laucevičius, Aleksandras; Huber, Heinrich J

2017-06-30

Numerous recent studies suggest the potential of circulating MicroRNAs (miRs) in peripheral blood samples as diagnostic or prognostic markers for coronary artery disease (CAD), acute coronary syndrome (ACS) and heart failure (HF). However, literature often remains inconclusive regarding as to which markers are most indicative for which of the above diseases. This shortcoming is mainly due to the lack of a systematic analyses and absence of information on the functional pathophysiological role of these miRs and their target genes. We here provide an-easy-to-use scoring approach to investigate the likelihood of regulation of several miRs and their target genes from literature by identifying consensus patterns of regulation. We therefore have screened over 1000 articles that study mRNA markers in cardiovascular and metabolic diseases, and devised a scoring algorithm to identify consensus means for miRs and genes regulation across several studies. We then aimed to identify differential markers between CAD, ACS and HF. We first identified miRs (miR-122, -126, -223, -138 and -370) as commonly regulated within a group of metabolic disease, while investigating cardiac-related pathologies (CAD, ACS, HF) revealed a decisive role of miR-1, -499, -208b, and -133a. Looking at differential markers between cardiovascular disease revealed miR-1, miR-208a and miR-133a to distinguish ACS and CAD to HF. Relating differentially expressed miRs to their putative gene targets using MirTarBase, we further identified HCN2/4 and LASP1 as potential markers of CAD and ACS, but not in HF. Likewise, BLC-2 was found oppositely regulated between CAD and HF. Interestingly, while studying overlap in target genes between CAD, ACS and HF only revealed little similarities, mapping these genes to gene ontology terms revealed a surprising similarity between CAD and ACS compared to HF. We conclude that our analysis using gene and miR scores allows the extraction of meaningful markers and the elucidation

Psychometric validation of the Persian nine-item Internet Gaming Disorder Scale – Short Form: Does gender and hours spent online gaming affect the interpretations of item descriptions?

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Wu, Tzu-Yi; Lin, Chung-Ying; Årestedt, Kristofer; Griffiths, Mark D.; Broström, Anders; Pakpour, Amir H.

2017-01-01

Background and aims The nine-item Internet Gaming Disorder Scale – Short Form (IGDS-SF9) is brief and effective to evaluate Internet Gaming Disorder (IGD) severity. Although its scores show promising psychometric properties, less is known about whether different groups of gamers interpret the items similarly. This study aimed to verify the construct validity of the Persian IGDS-SF9 and examine the scores in relation to gender and hours spent online gaming among 2,363 Iranian adolescents. Methods Confirmatory factor analysis (CFA) and Rasch analysis were used to examine the construct validity of the IGDS-SF9. The effects of gender and time spent online gaming per week were investigated by multigroup CFA and Rasch differential item functioning (DIF). Results The unidimensionality of the IGDS-SF9 was supported in both CFA and Rasch. However, Item 4 (fail to control or cease gaming activities) displayed DIF (DIF contrast = 0.55) slightly over the recommended cutoff in Rasch but was invariant in multigroup CFA across gender. Items 4 (DIF contrast = −0.67) and 9 (jeopardize or lose an important thing because of gaming activity; DIF contrast = 0.61) displayed DIF in Rasch and were non-invariant in multigroup CFA across time spent online gaming. Conclusions Given the Persian IGDS-SF9 was unidimensional, it is concluded that the instrument can be used to assess IGD severity. However, users of the instrument are cautioned concerning the comparisons of the sum scores of the IGDS-SF9 across gender and across adolescents spending different amounts of time online gaming. PMID:28571474

Identification and Development of Items Comprising Organizational Citizenship Behaviors Among Pharmacy Faculty.

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Desselle, Shane P; Semsick, Gretchen R

2016-12-25

Objective. Identify behaviors that can compose a measure of organizational citizenship by pharmacy faculty. Methods. A four-round, modified Delphi procedure using open-ended questions (Round 1) was conducted with 13 panelists from pharmacy academia. The items generated were evaluated and refined for inclusion in subsequent rounds. A consensus was reached after completing four rounds. Results. The panel produced a set of 26 items indicative of extra-role behaviors by faculty colleagues considered to compose a measure of citizenship, which is an expressed manifestation of collegiality. Conclusions. The items generated require testing for validation and reliability in a large sample to create a measure of organizational citizenship. Even prior to doing so, the list of items can serve as a resource for mentorship of junior and senior faculty alike.

Identification and Development of Items Comprising Organizational Citizenship Behaviors Among Pharmacy Faculty

Science.gov (United States)

Semsick, Gretchen R.

2016-01-01

Objective. Identify behaviors that can compose a measure of organizational citizenship by pharmacy faculty. Methods. A four-round, modified Delphi procedure using open-ended questions (Round 1) was conducted with 13 panelists from pharmacy academia. The items generated were evaluated and refined for inclusion in subsequent rounds. A consensus was reached after completing four rounds. Results. The panel produced a set of 26 items indicative of extra-role behaviors by faculty colleagues considered to compose a measure of citizenship, which is an expressed manifestation of collegiality. Conclusions. The items generated require testing for validation and reliability in a large sample to create a measure of organizational citizenship. Even prior to doing so, the list of items can serve as a resource for mentorship of junior and senior faculty alike. PMID:28179717

Complex versus Simple Modeling for DIF Detection: When the Intraclass Correlation Coefficient (?) of the Studied Item Is Less Than the ? of the Total Score

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Jin, Ying; Myers, Nicholas D.; Ahn, Soyeon

2014-01-01

Previous research has demonstrated that differential item functioning (DIF) methods that do not account for multilevel data structure could result in too frequent rejection of the null hypothesis (i.e., no DIF) when the intraclass correlation coefficient (?) of the studied item was the same as the ? of the total score. The current study extended…

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

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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.

Measuring resilience after spinal cord injury: Development, validation and psychometric characteristics of the SCI-QOL Resilience item bank and short form.

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Victorson, David; Tulsky, David S; Kisala, Pamela A; Kalpakjian, Claire Z; Weiland, Brian; Choi, Seung W

2015-05-01

To describe the development and psychometric properties of the Spinal Cord Injury--Quality of Life (SCI-QOL) Resilience item bank and short form. Using a mixed-methods design, we developed and tested a resilience item bank through the use of focus groups with individuals with SCI and clinicians with expertise in SCI, cognitive interviews, and item-response theory based analytic approaches, including tests of model fit and differential item functioning (DIF). We tested a 32-item pool at several medical institutions across the United States, including the University of Michigan, Kessler Foundation, the Rehabilitation Institute of Chicago, the University of Washington, Craig Hospital and the James J. Peters/Bronx Department of Veterans Affairs medical center. A total of 717 individuals with SCI completed the Resilience items. A unidimensional model was observed (CFI=0.968; RMSEA=0.074) and measurement precision was good (theta range between -3.1 and 0.9). Ten items were flagged for DIF, however, after examination of effect sizes we found this to be negligible with little practical impact on score estimates. The final calibrated item bank resulted in 21 retained items. This study indicates that the SCI-QOL Resilience item bank represents a psychometrically robust measurement tool. Short form items are also suggested and computer adaptive tests are available.

Validation of the TAPS-1: A Four-Item Screening Tool to Identify Unhealthy Substance Use in Primary Care.

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Gryczynski, Jan; McNeely, Jennifer; Wu, Li-Tzy; Subramaniam, Geetha A; Svikis, Dace S; Cathers, Lauretta A; Sharma, Gaurav; King, Jacqueline; Jelstrom, Eve; Nordeck, Courtney D; Sharma, Anjalee; Mitchell, Shannon G; O'Grady, Kevin E; Schwartz, Robert P

2017-09-01

The Tobacco, Alcohol, Prescription Medication, and Other Substance use (TAPS) tool is a combined two-part screening and brief assessment developed for adult primary care patients. The tool's first-stage screening component (TAPS-1) consists of four items asking about past 12-month use for four substance categories, with response options of never, less than monthly, monthly, weekly, and daily or almost daily. To validate the TAPS-1 in primary care patients. Participants completed the TAPS tool in self- and interviewer-administered formats, in random order. In this secondary analysis, the TAPS-1 was evaluated against DSM-5 substance use disorder (SUD) criteria to determine optimal cut-points for identifying unhealthy substance use at three severity levels (problem use, mild SUD, and moderate-to-severe SUD). Two thousand adult patients at five primary care sites. DSM-5 SUD criteria were determined via the modified Composite International Diagnostic Interview. Oral fluid was used as a biomarker of recent drug use. Optimal frequency-of-use cut-points on the self-administered TAPS-1 for identifying SUDs were ≥ monthly use for tobacco and alcohol (sensitivity = 0.92 and 0.71, specificity = 0.80 and 0.85, AUC = 0.86 and 0.78, respectively) and any reported use for illicit drugs and prescription medication misuse (sensitivity = 0.93 and 0.89, specificity = 0.85 and 0.91, AUC = 0.89 and 0.90, respectively). The performance of the interviewer-administered format was similar. When administered first, the self-administered format yielded higher disclosure rates for past 12-month alcohol use, illicit drug use, and prescription medication misuse. Frequency of use alone did not provide sufficient information to discriminate between gradations of substance use problem severity. Among those who denied drug use on the TAPS-1, less than 4% had a drug-positive biomarker. The TAPS-1 can identify unhealthy substance use in primary care patients with a high level of accuracy

An Anthropologist among the Psychometricians: Assessment Events, Ethnography, and Differential Item Functioning in the Mongolian Gobi

Science.gov (United States)

Maddox, Bryan; Zumbo, Bruno D.; Tay-Lim, Brenda; Qu, Demin

2015-01-01

This article explores the potential for ethnographic observations to inform the analysis of test item performance. In 2010, a standardized, large-scale adult literacy assessment took place in Mongolia as part of the United Nations Educational, Scientific and Cultural Organization Literacy Assessment and Monitoring Programme (LAMP). In a novel form…

Guidelines for identifying suspect/counterfeit material

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

These guidelines are intended to assist users of products in identifying: substandard, misrepresented, or fraudulently marked items. The guidelines provide information about such topics as: precautions, inspection and testing, dispositioning identified items, installed inspection and reporting suspect/counterfeit materials. These guidelines apply to users who are developing procurement documents, product acceptance/verification methods, company procedures, work instructions, etc. The intent of these SM guidelines in relation to the Quality Assurance Program Description (QAPD) and implementing company Management Control Procedures is not to substitute or replace existing requirements, as defined in either the QAPD or company implementing instructions (Management Control Procedures). Instead, the guidelines are intended to provide a consolidated source of information addressing the issue of Suspect/Counterfeit materials. These guidelines provide an extensive suspect component listing and suspect indications listing. Users can quickly check their suspect items against the list of manufacturers products (i.e., type, LD. number, and nameplate information) by consulting either of these listings.

Transcriptional Profiling Identifies Location-Specific and Breed-Specific Differentially Expressed Genes in Embryonic Myogenesis in Anas Platyrhynchos.

Directory of Open Access Journals (Sweden)

Rong-Ping Zhang

Full Text Available Skeletal muscle growth and development are highly orchestrated processes involving significant changes in gene expressions. Differences in the location-specific and breed-specific genes and pathways involved have important implications for meat productions and meat quality. Here, RNA-Seq was performed to identify differences in the muscle deposition between two muscle locations and two duck breeds for functional genomics studies. To achieve those goals, skeletal muscle samples were collected from the leg muscle (LM and the pectoral muscle (PM of two genetically different duck breeds, Heiwu duck (H and Peking duck (P, at embryonic 15 days. Functional genomics studies were performed in two experiments: Experiment 1 directly compared the location-specific genes between PM and LM, and Experiment 2 compared the two breeds (H and P at the same developmental stage (embryonic 15 days. Almost 13 million clean reads were generated using Illumina technology (Novogene, Beijing, China on each library, and more than 70% of the reads mapped to the Peking duck (Anas platyrhynchos genome. A total of 168 genes were differentially expressed between the two locations analyzed in Experiment 1, whereas only 8 genes were differentially expressed when comparing the same location between two breeds in Experiment 2. Gene Ontology (GO and the Kyoto Encyclopedia of Genes and Genomes pathways (KEGG were used to functionally annotate DEGs (differentially expression genes. The DEGs identified in Experiment 1 were mainly involved in focal adhesion, the PI3K-Akt signaling pathway and ECM-receptor interaction pathways (corrected P-value<0.05. In Experiment 2, the DEGs were associated with only the ribosome signaling pathway (corrected P-value<0.05. In addition, quantitative real-time PCR was used to confirm 15 of the differentially expressed genes originally detected by RNA-Seq. A comparative transcript analysis of the leg and pectoral muscles of two duck breeds not only

Psychometric properties of the Epworth Sleepiness Scale: A factor analysis and item-response theory approach.

Science.gov (United States)

Pilcher, June J; Switzer, Fred S; Munc, Alec; Donnelly, Janet; Jellen, Julia C; Lamm, Claus

2018-04-01

The purpose of this study is to examine the psychometric properties of the Epworth Sleepiness Scale (ESS) in two languages, German and English. Students from a university in Austria (N = 292; 55 males; mean age = 18.71 ± 1.71 years; 237 females; mean age = 18.24 ± 0.88 years) and a university in the US (N = 329; 128 males; mean age = 18.71 ± 0.88 years; 201 females; mean age = 21.59 ± 2.27 years) completed the ESS. An exploratory-factor analysis was completed to examine dimensionality of the ESS. Item response theory (IRT) analyses were used to provide information about the response rates on the items on the ESS and provide differential item functioning (DIF) analyses to examine whether the items were interpreted differently between the two languages. The factor analyses suggest that the ESS measures two distinct sleepiness constructs. These constructs indicate that the ESS is probing sleepiness in settings requiring active versus passive responding. The IRT analyses found that overall, the items on the ESS perform well as a measure of sleepiness. However, Item 8 and to a lesser extent Item 6 were being interpreted differently by respondents in comparison to the other items. In addition, the DIF analyses showed that the responses between German and English were very similar indicating that there are only minor measurement differences between the two language versions of the ESS. These findings suggest that the ESS provides a reliable measure of propensity to sleepiness; however, it does convey a two-factor approach to sleepiness. Researchers and clinicians can use the German and English versions of the ESS but may wish to exclude Item 8 when calculating a total sleepiness score.

Development of a Short Version of MSQOL-54 Using Factor Analysis and Item Response Theory.

Directory of Open Access Journals (Sweden)

Rosalba Rosato

Full Text Available The Multiple Sclerosis Quality of Life-54 (MSQOL-54, 52 items grouped in 12 subscales plus two single items is the most used MS specific health related quality of life inventory.To develop a shortened version of the MSQOL-54.MSQOL-54 dimensionality and metric properties were investigated by confirmatory factor analysis (CFA and Rasch modelling (Partial Credit Model, PCM on MSQOL-54s completed by 473 MS patients. Their mean age was 41 years, 65% were women, and median Expanded Disability Status Scale (EDSS score was 2.0 (range 0-9.5. Differential item functioning (DIF was evaluated for gender, age and EDSS. Dimensionality of the resulting short version was assessed by exploratory factor analysis (EFA and CFA. Cognitive debriefing of the short instrument (vs. the original was then performed on 12 MS patients.CFA of MSQOL-54 subscales showed that the data fitted the overall model well. Two subscales (Role Limitations--Physical, Role Limitations--Emotional did not fit the PCM, and were removed; two other subscales (Health Perceptions, Social Function did not fit the model, but were retained as single items. Sexual Satisfaction (single-item subscale was also removed. The resulting MSQOL-29 consisted of 25 items grouped in 7 subscales, plus 4 single items. PCM fit statistics were within the acceptability range for all MSQOL-29 items except one which had significant DIF by age. EFA and CFA indicated adequate fit to the original two-factor (Physical and Mental Health Composites hypothesis. Cognitive debriefing confirmed that MSQOL-29 was acceptable and had lost no key items.The proposed MSQOL-29 is 50% shorter than MSQOL-54, yet preserves key quality of life dimensions. Prospective validation on a large, independent MS patient sample is ongoing.

The e-MSWS-12: improving the multiple sclerosis walking scale using item response theory.

Science.gov (United States)

Engelhard, Matthew M; Schmidt, Karen M; Engel, Casey E; Brenton, J Nicholas; Patek, Stephen D; Goldman, Myla D

2016-12-01

The Multiple Sclerosis Walking Scale (MSWS-12) is the predominant patient-reported measure of multiple sclerosis (MS) -elated walking ability, yet it had not been analyzed using item response theory (IRT), the emerging standard for patient-reported outcome (PRO) validation. This study aims to reduce MSWS-12 measurement error and facilitate computerized adaptive testing by creating an IRT model of the MSWS-12 and distributing it online. MSWS-12 responses from 284 subjects with MS were collected by mail and used to fit and compare several IRT models. Following model selection and assessment, subpopulations based on age and sex were tested for differential item functioning (DIF). Model comparison favored a one-dimensional graded response model (GRM). This model met fit criteria and explained 87 % of response variance. The performance of each MSWS-12 item was characterized using category response curves (CRCs) and item information. IRT-based MSWS-12 scores correlated with traditional MSWS-12 scores (r = 0.99) and timed 25-foot walk (T25FW) speed (r =  -0.70). Item 2 showed DIF based on age (χ 2  = 19.02, df = 5, p Item 11 showed DIF based on sex (χ 2  = 13.76, df = 5, p = 0.02). MSWS-12 measurement error depends on walking ability, but could be lowered by improving or replacing items with low information or DIF. The e-MSWS-12 includes IRT-based scoring, error checking, and an estimated T25FW derived from MSWS-12 responses. It is available at https://ms-irt.shinyapps.io/e-MSWS-12 .

Reduced-Item Food Audits Based on the Nutrition Environment Measures Surveys.

Science.gov (United States)

Partington, Susan N; Menzies, Tim J; Colburn, Trina A; Saelens, Brian E; Glanz, Karen

2015-10-01

The community food environment may contribute to obesity by influencing food choice. Store and restaurant audits are increasingly common methods for assessing food environments, but are time consuming and costly. A valid, reliable brief measurement tool is needed. The purpose of this study was to develop and validate reduced-item food environment audit tools for stores and restaurants. Nutrition Environment Measures Surveys for stores (NEMS-S) and restaurants (NEMS-R) were completed in 820 stores and 1,795 restaurants in West Virginia, San Diego, and Seattle. Data mining techniques (correlation-based feature selection and linear regression) were used to identify survey items highly correlated to total survey scores and produce reduced-item audit tools that were subsequently validated against full NEMS surveys. Regression coefficients were used as weights that were applied to reduced-item tool items to generate comparable scores to full NEMS surveys. Data were collected and analyzed in 2008-2013. The reduced-item tools included eight items for grocery, ten for convenience, seven for variety, and five for other stores; and 16 items for sit-down, 14 for fast casual, 19 for fast food, and 13 for specialty restaurants-10% of the full NEMS-S and 25% of the full NEMS-R. There were no significant differences in median scores for varying types of retail food outlets when compared to the full survey scores. Median in-store audit time was reduced 25%-50%. Reduced-item audit tools can reduce the burden and complexity of large-scale or repeated assessments of the retail food environment without compromising measurement quality. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

The Technical Quality of Test Items Generated Using a Systematic Approach to Item Writing.

Science.gov (United States)

Siskind, Theresa G.; Anderson, Lorin W.

The study was designed to examine the similarity of response options generated by different item writers using a systematic approach to item writing. The similarity of response options to student responses for the same item stems presented in an open-ended format was also examined. A non-systematic (subject matter expertise) approach and a…

78 FR 34130 - Notice of Intent to Repatriate Cultural Items: The Field Museum, Chicago, IL

Science.gov (United States)

2013-06-06

... Indian tribes or Native Hawaiian organizations, has determined that the cultural items listed in this... tribe or Native Hawaiian organization not identified in this notice that wish to claim these cultural....R50000] Notice of Intent to Repatriate Cultural Items: The Field Museum, Chicago, IL AGENCY: National...

Vending Machines: A Narrative Review of Factors Influencing Items Purchased.

Science.gov (United States)

Hua, Sophia V; Ickovics, Jeannette R

2016-10-01

Vending machines are a ubiquitous part of our food environments. Unfortunately, items found in vending machines tend to be processed foods and beverages high in salt, sugar, and/or fat. The purpose of this review is to describe intervention and case studies designed to promote healthier vending purchases by consumers and identify which manipulations are most effective. All studies analyzed were intervention or case studies that manipulated vending machines and analyzed sales or revenue data. This literature review is limited to studies conducted in the United States within the past 2 decades (ie, 1994 to 2015), regardless of study population or setting. Ten articles met these criteria based on a search conducted using PubMed. Study manipulations included price changes, increase in healthier items, changes to the advertisements wrapped around vending machines, and promotional signs such as a stoplight system to indicate healthfulness of items and to remind consumers to make healthy choices. Overall, seven studies had manipulations that resulted in statistically significant positive changes in purchasing behavior. Two studies used manipulations that did not influence consumer behavior, and one study was equivocal. Although there was no intervention pattern that ensured changes in purchasing, price reductions were most effective overall. Revenue from vending sales did not change substantially regardless of intervention, which will be important to foster initiation and sustainability of healthier vending. Future research should identify price changes that would balance healthier choices and revenue as well as better marketing to promote purchase of healthier items. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Criticality Safety Support to a Project Addressing SNM Legacy Items at LLNL

International Nuclear Information System (INIS)

Pearson, J S; Burch, J G; Dodson, K E; Huang, S T

2005-01-01

The programmatic, facility and criticality safety support staffs at the LLNL Plutonium Facility worked together to successfully develop and implement a project to process legacy (DNFSB Recommendation 94-1 and non-Environmental, Safety, and Health (ES and H) labeled) materials in storage. Over many years, material had accumulated in storage that lacked information to adequately characterize the material for current criticality safety controls used in the facility. Generally, the fissionable material mass information was well known, but other information such as form, impurities, internal packaging, and presence of internal moderating or reflecting materials were not well documented. In many cases, the material was excess to programmatic need, but such a determination was difficult with the little information given on MC and A labels and in the MC and A database. The material was not packaged as efficiently as possible, so it also occupied much more valuable storage space than was necessary. Although safe as stored, the inadequately characterized material posed a risk for criticality safety noncompliances if moved within the facility under current criticality safety controls. A Legacy Item Implementation Plan was developed and implemented to deal with this problem. Reasonable bounding conditions were determined for the material involved, and criticality safety evaluations were completed. Two appropriately designated glove boxes were identified and criticality safety controls were developed to safely inspect the material. Inspecting the material involved identifying containers of legacy material, followed by opening, evaluating, processing if necessary, characterizing and repackaging the material. Material from multiple containers was consolidated more efficiently thus decreasing the total number of stored items to about one half of the highest count. Current packaging requirements were implemented. Detailed characterization of the material was captured in databases

Design patterns for digital item types in higher education

NARCIS (Netherlands)

Draaijer, S.; Hartog, R.J.M.

2007-01-01

A set of design patterns for digital item types has been developed in response to challenges identified in various projects by teachers in higher education. The goal of the projects in question was to design and develop formative and summative tests, and to develop interactive learning material in

Generalizability theory and item response theory

NARCIS (Netherlands)

Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

2012-01-01

Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a

Sharing the cost of redundant items

DEFF Research Database (Denmark)

Hougaard, Jens Leth; Moulin, Hervé

2014-01-01

We ask how to share the cost of finitely many public goods (items) among users with different needs: some smaller subsets of items are enough to serve the needs of each user, yet the cost of all items must be covered, even if this entails inefficiently paying for redundant items. Typical examples...... are network connectivity problems when an existing (possibly inefficient) network must be maintained. We axiomatize a family cost ratios based on simple liability indices, one for each agent and for each item, measuring the relative worth of this item across agents, and generating cost allocation rules...... additive in costs....

A novel whole-cell lysate kinase assay identifies substrates of the p38 MAPK in differentiating myoblasts

Directory of Open Access Journals (Sweden)

Knight James DR

2012-03-01

Full Text Available Abstract Background The p38α mitogen-activated protein kinase (MAPK is a critical mediator of myoblast differentiation, and does so in part through the phosphorylation and regulation of several transcription factors and chromatin remodelling proteins. However, whether p38α is involved in processes other than gene regulation during myogenesis is currently unknown, and why other p38 isoforms cannot compensate for its loss is unclear. Methods To further characterise the involvement of p38α during myoblast differentiation, we developed and applied a simple technique for identifying relevant in vivo kinase substrates and their phosphorylation sites. In addition to identifying substrates for one kinase, the technique can be used in vitro to compare multiple kinases in the same experiment, and we made use of this to study the substrate specificities of the p38α and β isoforms. Results Applying the technique to p38α resulted in the identification of seven in vivo phosphorylation sites on six proteins, four of which are cytoplasmic, in lysate derived from differentiating myoblasts. An in vitro comparison with p38β revealed that substrate specificity does not discriminate these two isoforms, but rather that their distinguishing characteristic appears to be cellular localisation. Conclusion Our results suggest p38α has a novel cytoplasmic role during myogenesis and that its unique cellular localisation may be why p38β and other isoforms cannot compensate for its absence. The substrate-finding approach presented here also provides a necessary tool for studying the hundreds of protein kinases that exist and for uncovering the deeper mechanisms of phosphorylation-dependent cell signalling.

Generalizability theory and item response theory

OpenAIRE

Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

2012-01-01

Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a selected-response format. This chapter presents a short overview of how item response theory and generalizability theory were integrated to model such assessments. Further, the precision of the esti...

78 FR 22282 - Notice of Intent To Repatriate a Cultural Item: U.S. Department of the Interior, National Park...

Science.gov (United States)

2013-04-15

... Hawaiian organizations, has determined that the cultural item listed in this notice meets [[Page 22283... Hawaiian organization not identified in this notice that wish to claim the cultural item should submit a... tribe or Native Hawaiian organization not identified in this notice that wish to claim these cultural...

The randomly renewed general item and the randomly inspected item with exponential life distribution

International Nuclear Information System (INIS)

Schneeweiss, W.G.

1979-01-01

For a randomly renewed item the probability distributions of the time to failure and of the duration of down time and the expectations of these random variables are determined. Moreover, it is shown that the same theory applies to randomly checked items with exponential probability distribution of life such as electronic items. The case of periodic renewals is treated as an example. (orig.) [de

The co-occurrence of PTSD and dissociation: differentiating severe PTSD from dissociative-PTSD.

Science.gov (United States)

Armour, Cherie; Karstoft, Karen-Inge; Richardson, J Don

2014-08-01

A dissociative-posttraumatic stress disorder (PTSD) subtype has been included in the DSM-5. However, it is not yet clear whether certain socio-demographic characteristics or psychological/clinical constructs such as comorbid psychopathology differentiate between severe PTSD and dissociative-PTSD. The current study investigated the existence of a dissociative-PTSD subtype and explored whether a number of trauma and clinical covariates could differentiate between severe PTSD alone and dissociative-PTSD. The current study utilized a sample of 432 treatment seeking Canadian military veterans. Participants were assessed with the Clinician Administered PTSD Scale (CAPS) and self-report measures of traumatic life events, depression, and anxiety. CAPS severity scores were created reflecting the sum of the frequency and intensity items from each of the 17 PTSD and 3 dissociation items. The CAPS severity scores were used as indicators in a latent profile analysis (LPA) to investigate the existence of a dissociative-PTSD subtype. Subsequently, several covariates were added to the model to explore differences between severe PTSD alone and dissociative-PTSD. The LPA identified five classes: one of which constituted a severe PTSD group (30.5 %), and one of which constituted a dissociative-PTSD group (13.7 %). None of the included, demographic, trauma, or clinical covariates were significantly predictive of membership in the dissociative-PTSD group compared to the severe PTSD group. In conclusion, a significant proportion of individuals report high levels of dissociation alongside their PTSD, which constitutes a dissociative-PTSD subtype. Further investigation is needed to identify which factors may increase or decrease the likelihood of membership in a dissociative-PTSD subtype group compared to a severe PTSD only group.

On-line item control at a high enriched nuclear fuel fabrication facility

International Nuclear Information System (INIS)

Lewis, T.W.; Lewis, H.M.

1984-01-01

The on-line item control system at Nuclear Fuel Services, Inc., is a near-real time method capable of tracking uniquely identified items from creation through disposition. The system provides for improved control, timeliness, accuracy and usability of company information and the necessary data required to support the regulatory program for the protection against diversion of Special Nuclear Materials. The system consists of software applications (approximately 150 programs) with man/machine interface controls which provide facilities for correct data entry and for the protection of data integrity. This system went into stand-alone operation in September, 1983 after a twenty month parallel test run with the previous keybatched (manual forms) item control system

Application of the Commercial Grade Item (CGI) Dedication Process for Procurement of Nuclear Safety Related Items at Nuclear Power Plant Krsko (NEK)

International Nuclear Information System (INIS)

Heruc, Z.; Pozar, J.

1998-01-01

CGI procurement is a process whereby parts are brought without imposing Appendix B Quality Assurance requirements on the supplier, and than dedicated for use in safety-related applications. The dedication process involves 1) based upon required safety function, an engineering evaluation to identify critical characteristic of the item and specification of acceptance criteria; and 2) quality control activities to ensure the item(s) supplied meets the acceptance criteria specified. CGI Dedication supports the supply of certified components/parts for the plant operation in an environment where the number of nuclear qualified suppliers diminishes. It requires a more active role of the plant personnel, therefore presenting an additional burden on human resources, but at the same time increases the technical KNOW-HOW and improves the confidence of test and inspection data presented in the certificates. Very often it is also cost beneficial. This paper is a continuation to last year presentation of the introduction of this method into NEK's procurement process and presents the current approach and some practical examples. (author)

Differential proteomics analysis to identify proteins and pathways associated with male sterility of soybean using iTRAQ-based strategy.

Science.gov (United States)

Li, Jiajia; Ding, Xianlong; Han, Shaohuai; He, Tingting; Zhang, Hao; Yang, Longshu; Yang, Shouping; Gai, Junyi

2016-04-14

To further elucidate the molecular mechanism of cytoplasmic male sterility (CMS) in soybean, a differential proteomic analysis was completed between the CMS line NJCMS1A and its maintainer NJCMS1B using iTRAQ-based strategy. As a result, 180 differential abundance proteins (DAPs) were identified, of which, 60 were down-regulated and 120 were up-regulated in NJCMS1A compared with NJCMS1B. Bioinformatic analysis showed that 167 DAPs were annotated in 41 Gene Ontology functional groups, 106 DAPs were classified into 20 clusters of orthologous groups of protein categories, and 128 DAPs were enrichment in 53 KEGG pathways. Fifteen differential level proteins/genes with the same expression pattern were identified in the further conjoint analysis of DAPs and the previously reported differential expression genes. Moreover, multiple reaction monitoring test, qRT-PCR analysis and enzyme activity assay validated that the iTRAQ results were reliable. Based on functional analysis of DAPs, we concluded that male sterility in NJCMS1A might be related to insufficiencies in energy supply, unbalance of protein synthesis and degradation, disruption of flavonoid synthesis, programmed cell death, abnormalities of substance metabolism, etc. These results might facilitate our understanding of the molecular mechanisms behind CMS in soybean. Soybean is an important global crop that provides protein and oil. Heterosis is a significantly potential approach to increase the yield of soybean. Cytoplasmic male sterility (CMS) plays a vital role in the production of hybrid seeds. However, the genetic and molecular mechanisms of male sterility in soybean still need to be further elucidated. In the present paper, a differential proteomic analysis was carried out and the results showed that several key proteins involved in key pathways were associated with male sterility in soybean. This work provides a new insight to understand the genetic and molecular mechanisms underlying CMS in soybean

Ion beam studies of archaeological gold jewellery items

International Nuclear Information System (INIS)

Demortier, G.

1996-01-01

Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.)

Ion beam studies of archaeological gold jewellery items

Energy Technology Data Exchange (ETDEWEB)

Demortier, G [Facultes Universitaires Notre-Dame de la Paix, Namur (Belgium). Lab. d` Analyses par Reactions Nucleaires

1996-06-01

Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.).

Adults Living with Type 2 Diabetes: Kept Personal Health Information Items as Expressions of Need

Science.gov (United States)

Whetstone, Melinda

2013-01-01

This study investigated personal information behavior and information needs that 21 adults managing life with Type 2 diabetes identify explicitly and implicitly during discussions of item acquisition and use of health information items that are kept in their homes. Research drew upon a naturalistic lens, in that semi-structured interviews were…

78 FR 45964 - Notice of Intent To Repatriate a Cultural Item: U.S. Department of the Interior, National Park...

Science.gov (United States)

2013-07-30

... Hawaiian organizations, has determined that the cultural item listed in this notice meets the definition of... control of the cultural item to the lineal descendants, Indian tribes, or Native Hawaiian organizations... Native Hawaiian organization not identified in this notice that wish to claim the cultural item should...

Development of a questionnaire to assess patient satisfaction with allergen-specific immunotherapy in adults: item generation, item reduction, and preliminary validation

Directory of Open Access Journals (Sweden)

Justícia JL

2011-05-01

Full Text Available Jose Luis Justícia1, Eva Baró2, Victoria Cardona3, Pedro Guardia4, Pedro Ojeda5, José Maria Olaguíbel6, José Maria Vega7, Carmen Vidal81Medical Department, Stallergenes Ibérica, Barcelona, Spain; 2Health Outcomes Research Department, 3D Health Research, Barcelona, Spain; 3Hospital Vall d'Hebron, Barcelona, Spain; 4Hospital Virgen Macarena, Sevilla, Spain; 5Clínica de Asma y Alergia Dres. Ojeda, Madrid, Spain; 6Complejo Hospitalario de Navarra, Pamplona, Spain; 7Hospital Regional Universitario Carlos Haya Málaga, Spain; 8Complejo Hospitalario Universitario de Santiago, Santiago de Compostela, SpainBackground: Allergen-specific immunotherapy (SIT is a treatment capable of modifying the natural course of allergy, so ensuring good adherence to SIT is fundamental. Up until now there has not existed an instrument specifically developed to measure patient satisfaction with SIT, although its assessment could help us to comprehend better and improve treatment adherence and effectiveness. The aim of this study was to develop an instrument to measure adult patient satisfaction with SIT.Methods: Items were generated from a literature review, focus groups with allergic adult patients undergoing SIT, and a meeting with experts. Potential items were administered to allergic patients undergoing SIT in an observational, cross-sectional, multicenter study. Item reduction was based on quantitative and qualitative criteria. A preliminary assessment of feasibility, reliability, and validity of the retained items was performed.Results: An initial pool of 70 items was administered to 257 patients undergoing SIT. Fifty-four items were eliminated resulting in a provisional instrument with 16 items. Factor analysis yielded four factors that were identified as perceived efficacy, activities and environment, cost-benefit balance, and overall satisfaction, explaining 74.8% of variance. Ceiling and floor effects were negligible for overall score. Overall score was

A method to identify differential expression profiles of time-course gene data with Fourier transformation.

Science.gov (United States)

Kim, Jaehee; Ogden, Robert Todd; Kim, Haseong

2013-10-18

Time course gene expression experiments are an increasingly popular method for exploring biological processes. Temporal gene expression profiles provide an important characterization of gene function, as biological systems are both developmental and dynamic. With such data it is possible to study gene expression changes over time and thereby to detect differential genes. Much of the early work on analyzing time series expression data relied on methods developed originally for static data and thus there is a need for improved methodology. Since time series expression is a temporal process, its unique features such as autocorrelation between successive points should be incorporated into the analysis. This work aims to identify genes that show different gene expression profiles across time. We propose a statistical procedure to discover gene groups with similar profiles using a nonparametric representation that accounts for the autocorrelation in the data. In particular, we first represent each profile in terms of a Fourier basis, and then we screen out genes that are not differentially expressed based on the Fourier coefficients. Finally, we cluster the remaining gene profiles using a model-based approach in the Fourier domain. We evaluate the screening results in terms of sensitivity, specificity, FDR and FNR, compare with the Gaussian process regression screening in a simulation study and illustrate the results by application to yeast cell-cycle microarray expression data with alpha-factor synchronization.The key elements of the proposed methodology: (i) representation of gene profiles in the Fourier domain; (ii) automatic screening of genes based on the Fourier coefficients and taking into account autocorrelation in the data, while controlling the false discovery rate (FDR); (iii) model-based clustering of the remaining gene profiles. Using this method, we identified a set of cell-cycle-regulated time-course yeast genes. The proposed method is general and can be

48 CFR 252.211-7007 - Reporting of Government-Furnished Equipment in the DoD Item Unique Identification (IUID) Registry.

Science.gov (United States)

2010-10-01

... property, equipment, machine tools, or similar capital items. Unique item identifier (UII) means a set of... management of Government-furnished equipment shall be performed at the item level; and (2) Unless provided by... payments; (6) Intellectual property or software; or (7) Real property. (d) Procedures for establishing UIIs...

The Effects of Test Length and Sample Size on Item Parameters in Item Response Theory

Science.gov (United States)

Sahin, Alper; Anil, Duygu

2017-01-01

This study investigates the effects of sample size and test length on item-parameter estimation in test development utilizing three unidimensional dichotomous models of item response theory (IRT). For this purpose, a real language test comprised of 50 items was administered to 6,288 students. Data from this test was used to obtain data sets of…

The effect of differential motivation on IRT linking

NARCIS (Netherlands)

Mittelhaëuser, M.A.; Béguin, A.A.; Sijtsma, K.

2015-01-01

The purpose of this study was to investigate whether simulated differential motivation between the stakes for operational tests and anchor items produces an invalid linking result if the Rasch model is used to link the operational tests. This was done for an external anchor design and a variation of

Approximation Preserving Reductions among Item Pricing Problems

Science.gov (United States)

Hamane, Ryoso; Itoh, Toshiya; Tomita, Kouhei

When a store sells items to customers, the store wishes to determine the prices of the items to maximize its profit. Intuitively, if the store sells the items with low (resp. high) prices, the customers buy more (resp. less) items, which provides less profit to the store. So it would be hard for the store to decide the prices of items. Assume that the store has a set V of n items and there is a set E of m customers who wish to buy those items, and also assume that each item i ∈ V has the production cost di and each customer ej ∈ E has the valuation vj on the bundle ej ⊆ V of items. When the store sells an item i ∈ V at the price ri, the profit for the item i is pi = ri - di. The goal of the store is to decide the price of each item to maximize its total profit. We refer to this maximization problem as the item pricing problem. In most of the previous works, the item pricing problem was considered under the assumption that pi ≥ 0 for each i ∈ V, however, Balcan, et al. [In Proc. of WINE, LNCS 4858, 2007] introduced the notion of “loss-leader, ” and showed that the seller can get more total profit in the case that pi < 0 is allowed than in the case that pi < 0 is not allowed. In this paper, we derive approximation preserving reductions among several item pricing problems and show that all of them have algorithms with good approximation ratio.

Which Statistic Should Be Used to Detect Item Preknowledge When the Set of Compromised Items Is Known?

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Sinharay, Sandip

2017-09-01

Benefiting from item preknowledge is a major type of fraudulent behavior during educational assessments. Belov suggested the posterior shift statistic for detection of item preknowledge and showed its performance to be better on average than that of seven other statistics for detection of item preknowledge for a known set of compromised items. Sinharay suggested a statistic based on the likelihood ratio test for detection of item preknowledge; the advantage of the statistic is that its null distribution is known. Results from simulated and real data and adaptive and nonadaptive tests are used to demonstrate that the Type I error rate and power of the statistic based on the likelihood ratio test are very similar to those of the posterior shift statistic. Thus, the statistic based on the likelihood ratio test appears promising in detecting item preknowledge when the set of compromised items is known.

Measuring self-esteem after spinal cord injury: Development, validation and psychometric characteristics of the SCI-QOL Self-esteem item bank and short form.

Science.gov (United States)

Kalpakjian, Claire Z; Tate, Denise G; Kisala, Pamela A; Tulsky, David S

2015-05-01

To describe the development and psychometric properties of the Spinal Cord Injury-Quality of Life (SCI-QOL) Self-esteem item bank. Using a mixed-methods design, we developed and tested a self-esteem item bank through the use of focus groups with individuals with SCI and clinicians with expertise in SCI, cognitive interviews, and item-response theory-(IRT) based analytic approaches, including tests of model fit, differential item functioning (DIF) and precision. We tested a pool of 30 items at several medical institutions across the United States, including the University of Michigan, Kessler Foundation, the Rehabilitation Institute of Chicago, the University of Washington, Craig Hospital, and the James J. Peters/Bronx Department of Veterans Affairs hospital. A total of 717 individuals with SCI completed the self-esteem items. A unidimensional model was observed (CFI=0.946; RMSEA=0.087) and measurement precision was good (theta range between -2.7 and 0.7). Eleven items were flagged for DIF; however, effect sizes were negligible with little practical impact on score estimates. The final calibrated item bank resulted in 23 retained items. This study indicates that the SCI-QOL Self-esteem item bank represents a psychometrically robust measurement tool. Short form items are also suggested and computer adaptive tests are available.

78 FR 13889 - Notice of Intent To Repatriate Cultural Items: Arizona State Museum, University of Arizona...

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2013-03-01

... the Hopi Tribe gives a positive identification to substantiate ownership of these sacred and religious... and religious items as described. These items are identified as sacred and religious objects, and are... definition of sacred objects and objects of cultural patrimony, and repatriation to the Indian tribe stated...

78 FR 50109 - Notice of Intent To Repatriate Cultural Items: Thomas Burke Memorial Washington State Museum...

Science.gov (United States)

2013-08-16

... with the appropriate Indian tribes or Native Hawaiian organizations, has determined that the cultural... organization not identified in this notice that wish to claim these cultural items should submit a written....R50000] Notice of Intent To Repatriate Cultural Items: Thomas Burke Memorial Washington State Museum...

Factoring handedness data: I. Item analysis.

Science.gov (United States)

Messinger, H B; Messinger, M I

1995-12-01

Recently in this journal Peters and Murphy challenged the validity of factor analyses done on bimodal handedness data, suggesting instead that right- and left-handers be studied separately. But bimodality may be avoidable if attention is paid to Oldfield's questionnaire format and instructions for the subjects. Two characteristics appear crucial: a two-column LEFT-RIGHT format for the body of the instrument and what we call Oldfield's Admonition: not to indicate strong preference for handedness item, such as write, unless "... the preference is so strong that you would never try to use the other hand unless absolutely forced to...". Attaining unimodality of an item distribution would seem to overcome the objections of Peters and Murphy. In a 1984 survey in Boston we used Oldfield's ten-item questionnaire exactly as published. This produced unimodal item distributions. With reflection of the five-point item scale and a logarithmic transformation, we achieved a degree of normalization for the items. Two surveys elsewhere based on Oldfield's 20-item list but with changes in the questionnaire format and the instructions, yielded markedly different item distributions with peaks at each extreme and sometimes in the middle as well.

Novel statistical framework to identify differentially expressed genes allowing transcriptomic background differences.

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Ling, Zhi-Qiang; Wang, Yi; Mukaisho, Kenichi; Hattori, Takanori; Tatsuta, Takeshi; Ge, Ming-Hua; Jin, Li; Mao, Wei-Min; Sugihara, Hiroyuki

2010-06-01

Tests of differentially expressed genes (DEGs) from microarray experiments are based on the null hypothesis that genes that are irrelevant to the phenotype/stimulus are expressed equally in the target and control samples. However, this strict hypothesis is not always true, as there can be several transcriptomic background differences between target and control samples, including different cell/tissue types, different cell cycle stages and different biological donors. These differences lead to increased false positives, which have little biological/medical significance. In this article, we propose a statistical framework to identify DEGs between target and control samples from expression microarray data allowing transcriptomic background differences between these samples by introducing a modified null hypothesis that the gene expression background difference is normally distributed. We use an iterative procedure to perform robust estimation of the null hypothesis and identify DEGs as outliers. We evaluated our method using our own triplicate microarray experiment, followed by validations with reverse transcription-polymerase chain reaction (RT-PCR) and on the MicroArray Quality Control dataset. The evaluations suggest that our technique (i) results in less false positive and false negative results, as measured by the degree of agreement with RT-PCR of the same samples, (ii) can be applied to different microarray platforms and results in better reproducibility as measured by the degree of DEG identification concordance both intra- and inter-platforms and (iii) can be applied efficiently with only a few microarray replicates. Based on these evaluations, we propose that this method not only identifies more reliable and biologically/medically significant DEG, but also reduces the power-cost tradeoff problem in the microarray field. Source code and binaries freely available for download at http://comonca.org.cn/fdca/resources/softwares/deg.zip.

Item Modeling Concept Based on Multimedia Authoring

Directory of Open Access Journals (Sweden)

Janez Stergar

2008-09-01

Full Text Available In this paper a modern item design framework for computer based assessment based on Flash authoring environment will be introduced. Question design will be discussed as well as the multimedia authoring environment used for item modeling emphasized. Item type templates are a structured means of collecting and storing item information that can be used to improve the efficiency and security of the innovative item design process. Templates can modernize the item design, enhance and speed up the development process. Along with content creation, multimedia has vast potential for use in innovative testing. The introduced item design template is based on taxonomy of innovative items which have great potential for expanding the content areas and construct coverage of an assessment. The presented item design approach is based on GUI's – one for question design based on implemented item design templates and one for user interaction tracking/retrieval. The concept of user interfaces based on Flash technology will be discussed as well as implementation of the innovative approach of the item design forms with multimedia authoring. Also an innovative method for user interaction storage/retrieval based on PHP extending Flash capabilities in the proposed framework will be introduced.

Control of Suspect/Counterfeit and Defective Items

Energy Technology Data Exchange (ETDEWEB)

Sheriff, Marnelle L.

2013-09-03

This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

The medial temporal lobes distinguish between within-item and item-context relations during autobiographical memory retrieval.

Science.gov (United States)

Sheldon, Signy; Levine, Brian

2015-12-01

During autobiographical memory retrieval, the medial temporal lobes (MTL) relate together multiple event elements, including object (within-item relations) and context (item-context relations) information, to create a cohesive memory. There is consistent support for a functional specialization within the MTL according to these relational processes, much of which comes from recognition memory experiments. In this study, we compared brain activation patterns associated with retrieving within-item relations (i.e., associating conceptual and sensory-perceptual object features) and item-context relations (i.e., spatial relations among objects) with respect to naturalistic autobiographical retrieval. We developed a novel paradigm that cued participants to retrieve information about past autobiographical events, non-episodic within-item relations, and non-episodic item-context relations with the perceptuomotor aspects of retrieval equated across these conditions. We used multivariate analysis techniques to extract common and distinct patterns of activity among these conditions within the MTL and across the whole brain, both in terms of spatial and temporal patterns of activity. The anterior MTL (perirhinal cortex and anterior hippocampus) was preferentially recruited for generating within-item relations later in retrieval whereas the posterior MTL (posterior parahippocampal cortex and posterior hippocampus) was preferentially recruited for generating item-context relations across the retrieval phase. These findings provide novel evidence for functional specialization within the MTL with respect to naturalistic memory retrieval. © 2015 Wiley Periodicals, Inc.

Methylation profiling identified novel differentially methylated markers including OPCML and FLRT2 in prostate cancer.

Science.gov (United States)

Wu, Yu; Davison, Jerry; Qu, Xiaoyu; Morrissey, Colm; Storer, Barry; Brown, Lisha; Vessella, Robert; Nelson, Peter; Fang, Min

2016-04-02

To develop new methods to distinguish indolent from aggressive prostate cancers (PCa), we utilized comprehensive high-throughput array-based relative methylation (CHARM) assay to identify differentially methylated regions (DMRs) throughout the genome, including both CpG island (CGI) and non-CGI regions in PCa patients based on Gleason grade. Initially, 26 samples, including 8 each of low [Gleason score (GS) 6] and high (GS ≥7) grade PCa samples and 10 matched normal prostate tissues, were analyzed as a discovery cohort. We identified 3,567 DMRs between normal and cancer tissues, and 913 DMRs distinguishing low from high-grade cancers. Most of these DMRs were located at CGI shores. The top 5 candidate DMRs from the low vs. high Gleason comparison, including OPCML, ELAVL2, EXT1, IRX5, and FLRT2, were validated by pyrosequencing using the discovery cohort. OPCML and FLRT2 were further validated in an independent cohort consisting of 20 low-Gleason and 33 high-Gleason tissues. We then compared patients with biochemical recurrence (n=70) vs. those without (n=86) in a third cohort, and they showed no difference in methylation at these DMR loci. When GS 3+4 cases and GS 4+3 cases were compared, OPCML-DMR methylation showed a trend of lower methylation in the recurrence group (n=30) than in the no-recurrence (n=52) group. We conclude that whole-genome methylation profiling with CHARM revealed distinct patterns of differential DNA methylation between normal prostate and PCa tissues, as well as between different risk groups of PCa as defined by Gleason scores. A panel of selected DMRs may serve as novel surrogate biomarkers for Gleason score in PCa.

A strategy for optimizing item-pool management

NARCIS (Netherlands)

Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

2006-01-01

Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

Model EPQ Multi Item yang Dimodifikasi untuk Dua Permintaan secara Simultan

Directory of Open Access Journals (Sweden)

Taufiq Rahman

2017-05-01

Full Text Available Inventory is one of many factors of the business operation that need to be controlled by industries in order to improve efficiency, enhance productivity, and decrease the holding cost. The holding cost of inventories in supply chain contribute to 20% - 40% of the product value. It can be controlled by applying appropriate inventory model, such as EPQ/Economic Production Quantity and EOQ/Economic Order Quantity. EPQ is an inventory model that used to determine the optimum production lot size with balanced the production setup cost and holding cost. Even the classic EPQ has applied widely in industries, the assumption used by this model differed between the researchers whether it is continuous or discrete demand, because the multi delivery or discrete demand is mostly used by industries. Even so, there are industries that used both continuous and discrete demand simultaneously. Based on previous research, there was an advanced EPQ model that synchronizing both assumptions simultaneously, but it still addressed single item problem. Since almost the industries produced multi item, this model has lack of applicability. Therefore, this research proposed a multi item EPQ Model that synchronizing continuous and discrete demand simultaneously. The solution procedure that used in this proposed model are classical calculus method/differential calculus and simultaneous approach. A numerical example is given to show the effectiveness of the proposed approach based on the data from the literature.

[The Spanish adapted version of the Children's Communication Checklist identifies disorders of pragmatic use of language and differentiates between clinical subtypes].

Science.gov (United States)

Crespo-Eguilaz, N; Magallon, S; Sanchez-Carpintero, R; Narbona, J

2016-01-01

The Children's Communication Checklist (CCC) by Bishop is a useful scale for evaluation of pragmatic verbal abilities in school children. The aim of the study is to ascertain the validity and reliability of the CCC in Spanish. Answers to the CCC items by parents of 360 children with normal intelligence were analyzed. There were five groups: 160 control children; 68 children with attention deficit hyperactivity disorder, 77 with procedural non-verbal disorder, 25 children with social communication disorder and 30 with autism spectrum disorder. Investigations included: factorial analysis in order to cluster checklist items, reliability analyses of the proposed scales and discriminant analysis to check whether the scale correctly classifies children with pragmatic verbal abilities. Seven factors were obtained (Kaiser-Meyer-Olkin: 0.852) with moderate similarity with those of the original scale: social relationships, interests, and five more that can be grouped into pragmatic verbal ability (conversational abilities, coherence-comprehension, empathy nonverbal communication and appropriateness). All factors are significantly correlated with each other in the control group, and the five that compose pragmatic verbal ability correlate with each other in the clinical groups (Pearson r). The scales have good reliability (Cronbach's alpha: 0.914). The questionnaire correctly classifies 98.9% of grouped cases with and without pragmatic disorder and 78% of subjects in their appropriate clinical group. Besides, the questionnaire allows to differentiate the pathologies according to the presence and intensity of the symptoms. This Spanish version of the CCC is highly valid and reliable. The proposed statistics can be used as normative-reference values.

Item response theory - A first approach

Science.gov (United States)

Nunes, Sandra; Oliveira, Teresa; Oliveira, Amílcar

2017-07-01

The Item Response Theory (IRT) has become one of the most popular scoring frameworks for measurement data, frequently used in computerized adaptive testing, cognitively diagnostic assessment and test equating. According to Andrade et al. (2000), IRT can be defined as a set of mathematical models (Item Response Models - IRM) constructed to represent the probability of an individual giving the right answer to an item of a particular test. The number of Item Responsible Models available to measurement analysis has increased considerably in the last fifteen years due to increasing computer power and due to a demand for accuracy and more meaningful inferences grounded in complex data. The developments in modeling with Item Response Theory were related with developments in estimation theory, most remarkably Bayesian estimation with Markov chain Monte Carlo algorithms (Patz & Junker, 1999). The popularity of Item Response Theory has also implied numerous overviews in books and journals, and many connections between IRT and other statistical estimation procedures, such as factor analysis and structural equation modeling, have been made repeatedly (Van der Lindem & Hambleton, 1997). As stated before the Item Response Theory covers a variety of measurement models, ranging from basic one-dimensional models for dichotomously and polytomously scored items and their multidimensional analogues to models that incorporate information about cognitive sub-processes which influence the overall item response process. The aim of this work is to introduce the main concepts associated with one-dimensional models of Item Response Theory, to specify the logistic models with one, two and three parameters, to discuss some properties of these models and to present the main estimation procedures.

Redefining diagnostic symptoms of depression using Rasch analysis: testing an item bank suitable for DSM-V and computer adaptive testing.

Science.gov (United States)

Mitchell, Alex J; Smith, Adam B; Al-salihy, Zerak; Rahim, Twana A; Mahmud, Mahmud Q; Muhyaldin, Asma S

2011-10-01

We aimed to redefine the optimal self-report symptoms of depression suitable for creation of an item bank that could be used in computer adaptive testing or to develop a simplified screening tool for DSM-V. Four hundred subjects (200 patients with primary depression and 200 non-depressed subjects), living in Iraqi Kurdistan were interviewed. The Mini International Neuropsychiatric Interview (MINI) was used to define the presence of major depression (DSM-IV criteria). We examined symptoms of depression using four well-known scales delivered in Kurdish. The Partial Credit Model was applied to each instrument. Common-item equating was subsequently used to create an item bank and differential item functioning (DIF) explored for known subgroups. A symptom level Rasch analysis reduced the original 45 items to 24 items of the original after the exclusion of 21 misfitting items. A further six items (CESD13 and CESD17, HADS-D4, HADS-D5 and HADS-D7, and CDSS3 and CDSS4) were removed due to misfit as the items were added together to form the item bank, and two items were subsequently removed following the DIF analysis by diagnosis (CESD20 and CDSS9, both of which were harder to endorse for women). Therefore the remaining optimal item bank consisted of 17 items and produced an area under the curve (AUC) of 0.987. Using a bank restricted to the optimal nine items revealed only minor loss of accuracy (AUC = 0.989, sensitivity 96%, specificity 95%). Finally, when restricted to only four items accuracy was still high (AUC was still 0.976; sensitivity 93%, specificity 96%). An item bank of 17 items may be useful in computer adaptive testing and nine or even four items may be used to develop a simplified screening tool for DSM-V major depressive disorder (MDD). Further examination of this item bank should be conducted in different cultural settings.

Scoring best-worst data in unbalanced many-item designs, with applications to crowdsourcing semantic judgments.

Science.gov (United States)

Hollis, Geoff

2018-04-01

Best-worst scaling is a judgment format in which participants are presented with a set of items and have to choose the superior and inferior items in the set. Best-worst scaling generates a large quantity of information per judgment because each judgment allows for inferences about the rank value of all unjudged items. This property of best-worst scaling makes it a promising judgment format for research in psychology and natural language processing concerned with estimating the semantic properties of tens of thousands of words. A variety of different scoring algorithms have been devised in the previous literature on best-worst scaling. However, due to problems of computational efficiency, these scoring algorithms cannot be applied efficiently to cases in which thousands of items need to be scored. New algorithms are presented here for converting responses from best-worst scaling into item scores for thousands of items (many-item scoring problems). These scoring algorithms are validated through simulation and empirical experiments, and considerations related to noise, the underlying distribution of true values, and trial design are identified that can affect the relative quality of the derived item scores. The newly introduced scoring algorithms consistently outperformed scoring algorithms used in the previous literature on scoring many-item best-worst data.

78 FR 22284 - Notice of Intent To Repatriate a Cultural Item: U.S. Department of the Interior, Bureau of Indian...

Science.gov (United States)

2013-04-15

... Hawaiian organization not identified in this notice that wish to claim this cultural item should submit a... tribe or Native Hawaiian organization not identified in this notice that wish to claim this cultural....R50000] Notice of Intent To Repatriate a Cultural Item: U.S. Department of the Interior, Bureau of Indian...

Psychometric evaluation of an item bank for computerized adaptive testing of the EORTC QLQ-C30 cognitive functioning dimension in cancer patients.

Science.gov (United States)

Dirven, Linda; Groenvold, Mogens; Taphoorn, Martin J B; Conroy, Thierry; Tomaszewski, Krzysztof A; Young, Teresa; Petersen, Morten Aa

2017-11-01

The European Organisation of Research and Treatment of Cancer (EORTC) Quality of Life Group is developing computerized adaptive testing (CAT) versions of all EORTC Quality of Life Questionnaire (QLQ-C30) scales with the aim to enhance measurement precision. Here we present the results on the field-testing and psychometric evaluation of the item bank for cognitive functioning (CF). In previous phases (I-III), 44 candidate items were developed measuring CF in cancer patients. In phase IV, these items were psychometrically evaluated in a large sample of international cancer patients. This evaluation included an assessment of dimensionality, fit to the item response theory (IRT) model, differential item functioning (DIF), and measurement properties. A total of 1030 cancer patients completed the 44 candidate items on CF. Of these, 34 items could be included in a unidimensional IRT model, showing an acceptable fit. Although several items showed DIF, these had a negligible impact on CF estimation. Measurement precision of the item bank was much higher than the two original QLQ-C30 CF items alone, across the whole continuum. Moreover, CAT measurement may on average reduce study sample sizes with about 35-40% compared to the original QLQ-C30 CF scale, without loss of power. A CF item bank for CAT measurement consisting of 34 items was established, applicable to various cancer patients across countries. This CAT measurement system will facilitate precise and efficient assessment of HRQOL of cancer patients, without loss of comparability of results.

Teaching children with autism spectrum disorders to mand for the removal of stimuli that prevent access to preferred items.

Science.gov (United States)

Shillingsburg, M Alice; Powell, Nicole M; Bowen, Crystal N

2013-01-01

Mand training is often a primary focus in early language instruction and typically includes mands that are positively reinforced. However, mands maintained by negative reinforcement are also important skills to teach. These include mands to escape aversive demands or unwanted items. Another type of negatively reinforced mand important to teach involves the removal of a stimulus that prevents access to a preferred activity. We taught 5 participants diagnosed with autism spectrum disorders to mand for the removal of a stimulus in order to access a preferred item that had been blocked. An evaluation was conducted to determine if participants responded differentially when the establishing operations for the preferred item were present versus absent. All participants learned to mand for the removal of the stimulus exclusively under conditions when the establishing operation was present.

Investigating Separate and Concurrent Approaches for Item Parameter Drift in 3PL Item Response Theory Equating

Science.gov (United States)

Arce-Ferrer, Alvaro J.; Bulut, Okan

2017-01-01

This study examines separate and concurrent approaches to combine the detection of item parameter drift (IPD) and the estimation of scale transformation coefficients in the context of the common item nonequivalent groups design with the three-parameter item response theory equating. The study uses real and synthetic data sets to compare the two…

Use of indicator items to monitor marine debris on a New Jersey beach from 1991 to 1996

Science.gov (United States)

Ribic, C.A.

1998-01-01

The US National Marine Debris Monitoring Program is using indicator items from beach surveys to identify whether amounts of marine debris are changing over time. Indicator items were selected through expert opinion and assumed to reflect the trend of all debris. We used monthly data from a 1991-1996 study of debris on a New Jersey beach to determine if indicator and non-indicator items showed similar trends. Total indicator debris levels did not change; this was true regardless of probable source. Non-indicator debris increased about 40% annually. Plastic non-indicator items increased regardless of whether items were whole items, cigarette filters, or pieces. Of the whole items, almost 50% were plastic lids, cups, and utensils, and about 25% were drug-related paraphernalia, tobacco-related products, plastic stirrers, pull rings, and fireworks. When indicator items are used in a monitoring programme to reflect total debris patterns, concordance of trends in indicator and non-indicator debris should be checked.

Service differentiation in spare parts supply through dedicated stocks

NARCIS (Netherlands)

Alvarez, Elisa; van der Heijden, Matthijs C.; Zijm, Willem H.M.

2012-01-01

We investigate keeping dedicated stocks at customer sites in addition to stock kept at some central location as a tool for applying service differentiation in spare parts supply. We study the resulting two-echelon system in a multi-item setting, both under backordering and under emergency shipments

76 FR 60474 - Commercial Item Handbook

Science.gov (United States)

2011-09-29

... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System Commercial Item Handbook AGENCY.... SUMMARY: DoD has updated its Commercial Item Handbook. The purpose of the Handbook is to help acquisition personnel develop sound business strategies for procuring commercial items. DoD is seeking industry input on...

Item response modeling: a psychometric assessment of the children's fruit, vegetable, water, and physical activity self-efficacy scales among Chinese children.

Science.gov (United States)

Wang, Jing-Jing; Chen, Tzu-An; Baranowski, Tom; Lau, Patrick W C

2017-09-16

This study aimed to evaluate the psychometric properties of four self-efficacy scales (i.e., self-efficacy for fruit (FSE), vegetable (VSE), and water (WSE) intakes, and physical activity (PASE)) and to investigate their differences in item functioning across sex, age, and body weight status groups using item response modeling (IRM) and differential item functioning (DIF). Four self-efficacy scales were administrated to 763 Hong Kong Chinese children (55.2% boys) aged 8-13 years. Classical test theory (CTT) was used to examine the reliability and factorial validity of scales. IRM was conducted and DIF analyses were performed to assess the characteristics of item parameter estimates on the basis of children's sex, age and body weight status. All self-efficacy scales demonstrated adequate to excellent internal consistency reliability (Cronbach's α: 0.79-0.91). One FSE misfit item and one PASE misfit item were detected. Small DIF were found for all the scale items across children's age groups. Items with medium to large DIF were detected in different sex and body weight status groups, which will require modification. A Wright map revealed that items covered the range of the distribution of participants' self-efficacy for each scale except VSE. Several self-efficacy scales' items functioned differently by children's sex and body weight status. Additional research is required to modify the four self-efficacy scales to minimize these moderating influences for application.

Gender and Socioeconomic Status DIF on The WISC-IV Turkish Form Items: A Comparison of DIF Detection Tecniques

Directory of Open Access Journals (Sweden)

Elif Bengi ÜNSAL ÖZBERK

2017-03-01

Full Text Available The purpose of this study is to investigate potential gender and socio-economic status bias in theWechler Intelligence Scale for Children: Fourth Edition (WISC-4 by using several differential item functioning detection techniques. In this study, WISC-4 Turkish standardization test pilot data including 817 children were used. In accordance with the purpose of the study, 315 items were used both in polytomously scored subtests such as Block Design, Similarities, Digit Span, Vocabulary, Letter-Number Sequencing, Comprehension, and dichotomously scored subtests such as Picture Concepts, Matrix Reasoning, Picture Completion, Information, Arithmetic, and Word Reasoning. While Rasch Model, Mantel-Haenszel, and SIBTEST DIF detection techniques were used for dichotomously scored items, Partila Credit Model, Mantel, and Poly-SIBTEST techniques were used for polytomously scored items. In terms of DIF techniques, Mantel-Haenszel, SIBTEST and Mantel Test, Poly-SIBTEST analyses provided similar results when DIF based on gender was investigated. In addition Mantel-Haenszel, Rasch estimations and Partial Credit Model, Mantel Test results were similar while investigating DIF according to socioeconomic status.

Spare Items validation

International Nuclear Information System (INIS)

Fernandez Carratala, L.

1998-01-01

There is an increasing difficulty for purchasing safety related spare items, with certifications by manufacturers for maintaining the original qualifications of the equipment of destination. The main reasons are, on the top of the logical evolution of technology, applied to the new manufactured components, the quitting of nuclear specific production lines and the evolution of manufacturers quality systems, originally based on nuclear codes and standards, to conventional industry standards. To face this problem, for many years different Dedication processes have been implemented to verify whether a commercial grade element is acceptable to be used in safety related applications. In the same way, due to our particular position regarding the spare part supplies, mainly from markets others than the american, C.N. Trillo has developed a methodology called Spare Items Validation. This methodology, which is originally based on dedication processes, is not a single process but a group of coordinated processes involving engineering, quality and management activities. These are to be performed on the spare item itself, its design control, its fabrication and its supply for allowing its use in destinations with specific requirements. The scope of application is not only focussed on safety related items, but also to complex design, high cost or plant reliability related components. The implementation in C.N. Trillo has been mainly curried out by merging, modifying and making the most of processes and activities which were already being performed in the company. (Author)

Item-saving assessment of self-care performance in children with developmental disabilities: A prospective caregiver-report computerized adaptive test

Science.gov (United States)

Chen, Cheng-Te; Chen, Yu-Lan; Lin, Yu-Ching; Hsieh, Ching-Lin; Tzeng, Jeng-Yi

2018-01-01

Objective The purpose of this study was to construct a computerized adaptive test (CAT) for measuring self-care performance (the CAT-SC) in children with developmental disabilities (DD) aged from 6 months to 12 years in a content-inclusive, precise, and efficient fashion. Methods The study was divided into 3 phases: (1) item bank development, (2) item testing, and (3) a simulation study to determine the stopping rules for the administration of the CAT-SC. A total of 215 caregivers of children with DD were interviewed with the 73-item CAT-SC item bank. An item response theory model was adopted for examining the construct validity to estimate item parameters after investigation of the unidimensionality, equality of slope parameters, item fitness, and differential item functioning (DIF). In the last phase, the reliability and concurrent validity of the CAT-SC were evaluated. Results The final CAT-SC item bank contained 56 items. The stopping rules suggested were (a) reliability coefficient greater than 0.9 or (b) 14 items administered. The results of simulation also showed that 85% of the estimated self-care performance scores would reach a reliability higher than 0.9 with a mean test length of 8.5 items, and the mean reliability for the rest was 0.86. Administering the CAT-SC could reduce the number of items administered by 75% to 84%. In addition, self-care performances estimated by the CAT-SC and the full item bank were very similar to each other (Pearson r = 0.98). Conclusion The newly developed CAT-SC can efficiently measure self-care performance in children with DD whose performances are comparable to those of TD children aged from 6 months to 12 years as precisely as the whole item bank. The item bank of the CAT-SC has good reliability and a unidimensional self-care construct, and the CAT can estimate self-care performance with less than 25% of the items in the item bank. Therefore, the CAT-SC could be useful for measuring self-care performance in children with

Using Item Analysis to Assess Objectively the Quality of the Calgary-Cambridge OSCE Checklist

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Tyrone Donnon

2011-06-01

Full Text Available Background:  The purpose of this study was to investigate the use of item analysis to assess objectively the quality of items on the Calgary-Cambridge Communications OSCE checklist. Methods:  A total of 150 first year medical students were provided with extensive teaching on the use of the Calgary-Cambridge Guidelines for interviewing patients and participated in a final year end 20 minute communication OSCE station.  Grouped into either the upper half (50% or lower half (50% communication skills performance groups, discrimination, difficulty and point biserial values were calculated for each checklist item. Results:  The mean score on the 33 item communication checklist was 24.09 (SD = 4.46 and the internal reliability coefficient was ? = 0.77. Although most of the items were found to have moderate (k = 12, 36% or excellent (k = 10, 30% discrimination values, there were 6 (18% identified as ‘fair’ and 3 (9% as ‘poor’. A post-examination review focused on item analysis findings resulted in an increase in checklist reliability (? = 0.80. Conclusions:  Item analysis has been used with MCQ exams extensively. In this study, it was also found to be an objective and practical approach to use in evaluating the quality of a standardized OSCE checklist.

Initial Q-list for the prospective Yucca Mountain repository based on items important to safety and waste isolation

International Nuclear Information System (INIS)

Laub, T.W.; Jardine, L.J.

1987-01-01

A method for identifying items important to safety based on a probabilistic risk assessment approach was developed and implemented for the conceptual design of the Yucca Mountain repository. No items were classified as important to safety; however, six items were classified as potentially important to safety. These were the shipping cask, the cranes and the truck or rail-care vehicle stops in the cask receiving and preparation area, the hot cell structure of the waste packaging hot cells, the cranes in the waste packaging hot cells, and the waste-handling building fire protection system. In addition, a method for identifying items important to waste isolation was developed and implemented. Two hydrogeologic units of the Yucca Mountain site were classified as important to waste isolation: the Calico Hills nonwelded zeolitic unit and the Calico Hills nonwelded vitric unit. The preliminary Q-list for the Yucca Mountain repository is comprised of the two units of the site classified as important to waste isolation and contains no items important to safety

Initial Q-list for the prospective Yucca Mountain repository based on items important to safety and waste isolation

International Nuclear Information System (INIS)

Laub, T.W.; Jardine, L.J.

1987-01-01

A method for identifying items important to safety based on a probabilistic risk assessment approach was developed and implemented for the conceptual design of the Yucca Mountain repository. No items were classified as important to safety; however, six items were classified as potentially important to safety. These were the shipping cask, the cranes and the truck or rail-car vehicle stops in the cask receiving and preparation area, the hot cell structure of the waste packaging hot cells, the cranes in the waste packaging hot cells, and the waste-handling building fire protection system. In addition, a method for identifying items important to waste isolation was developed and implemented. Two hydrogeologic units of the Yucca Mountain site were classified as important to waste isolation: the Calico Hills nonwelded zeolitic unit and the Calico Hills nonwelded vitric unit. The preliminary Q-list for the Yucca Mountain repository is comprised of the two units of the site classified as important to waste isolation and contains no items important to safety

A Comparison of the 27-Item and 12-Item Intolerance of Uncertainty Scales

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Khawaja, Nigar G.; Yu, Lai Ngo Heidi

2010-01-01

The 27-item Intolerance of Uncertainty Scale (IUS) has become one of the most frequently used measures of Intolerance of Uncertainty. More recently, an abridged, 12-item version of the IUS has been developed. The current research used clinical (n = 50) and non-clinical (n = 56) samples to examine and compare the psychometric properties of both…

More is not Always Better: The Relation between Item Response and Item Response Time in Raven’s Matrices

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Frank Goldhammer

2015-03-01

Full Text Available The role of response time in completing an item can have very different interpretations. Responding more slowly could be positively related to success as the item is answered more carefully. However, the association may be negative if working faster indicates higher ability. The objective of this study was to clarify the validity of each assumption for reasoning items considering the mode of processing. A total of 230 persons completed a computerized version of Raven’s Advanced Progressive Matrices test. Results revealed that response time overall had a negative effect. However, this effect was moderated by items and persons. For easy items and able persons the effect was strongly negative, for difficult items and less able persons it was less negative or even positive. The number of rules involved in a matrix problem proved to explain item difficulty significantly. Most importantly, a positive interaction effect between the number of rules and item response time indicated that the response time effect became less negative with an increasing number of rules. Moreover, exploratory analyses suggested that the error type influenced the response time effect.

Developing core elements and checklist items for global hospital antimicrobial stewardship programmes: a consensus approach.

Science.gov (United States)

Pulcini, C; Binda, F; Lamkang, A S; Trett, A; Charani, E; Goff, D A; Harbarth, S; Hinrichsen, S L; Levy-Hara, G; Mendelson, M; Nathwani, D; Gunturu, R; Singh, S; Srinivasan, A; Thamlikitkul, V; Thursky, K; Vlieghe, E; Wertheim, H; Zeng, M; Gandra, S; Laxminarayan, R

2018-04-03

With increasing global interest in hospital antimicrobial stewardship (AMS) programmes, there is a strong demand for core elements of AMS to be clearly defined on the basis of principles of effectiveness and affordability. To date, efforts to identify such core elements have been limited to Europe, Australia, and North America. The aim of this study was to develop a set of core elements and their related checklist items for AMS programmes that should be present in all hospitals worldwide, regardless of resource availability. A literature review was performed by searching Medline and relevant websites to retrieve a list of core elements and items that could have global relevance. These core elements and items were evaluated by an international group of AMS experts using a structured modified Delphi consensus procedure, using two-phased online in-depth questionnaires. The literature review identified seven core elements and their related 29 checklist items from 48 references. Fifteen experts from 13 countries in six continents participated in the consensus procedure. Ultimately, all seven core elements were retained, as well as 28 of the initial checklist items plus one that was newly suggested, all with ≥80% agreement; 20 elements and items were rephrased. This consensus on core elements for hospital AMS programmes is relevant to both high- and low-to-middle-income countries and could facilitate the development of national AMS stewardship guidelines and adoption by healthcare settings worldwide. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. All rights reserved.

Item response theory analysis applied to the Spanish version of the Personal Outcomes Scale.

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Guàrdia-Olmos, J; Carbó-Carreté, M; Peró-Cebollero, M; Giné, C

2017-11-01

The study of measurements of quality of life (QoL) is one of the great challenges of modern psychology and psychometric approaches. This issue has greater importance when examining QoL in populations that were historically treated on the basis of their deficiency, and recently, the focus has shifted to what each person values and desires in their life, as in cases of people with intellectual disability (ID). Many studies of QoL scales applied in this area have attempted to improve the validity and reliability of their components by incorporating various sources of information to achieve consistency in the data obtained. The adaptation of the Personal Outcomes Scale (POS) in Spanish has shown excellent psychometric attributes, and its administration has three sources of information: self-assessment, practitioner and family. The study of possible congruence or incongruence of observed distributions of each item between sources is therefore essential to ensure a correct interpretation of the measure. The aim of this paper was to analyse the observed distribution of items and dimensions from the three Spanish POS information sources cited earlier, using the item response theory. We studied a sample of 529 people with ID and their respective practitioners and family member, and in each case, we analysed items and factors using Samejima's model of polytomic ordinal scales. The results indicated an important number of items with differential effects regarding sources, and in some cases, they indicated significant differences in the distribution of items, factors and sources of information. As a result of this analysis, we must affirm that the administration of the POS, considering three sources of information, was adequate overall, but a correct interpretation of the results requires that it obtain much more information to consider, as well as some specific items in specific dimensions. The overall ratings, if these comments are considered, could result in bias. © 2017

Modeling the Severity of Drinking Consequences in First-Year College Women: An Item Response Theory Analysis of the Rutgers Alcohol Problem Index*

Science.gov (United States)

Cohn, Amy M.; Hagman, Brett T.; Graff, Fiona S.; Noel, Nora E.

2011-01-01

Objective: The present study examined the latent continuum of alcohol-related negative consequences among first-year college women using methods from item response theory and classical test theory. Method: Participants (N = 315) were college women in their freshman year who reported consuming any alcohol in the past 90 days and who completed assessments of alcohol consumption and alcohol-related negative consequences using the Rutgers Alcohol Problem Index. Results: Item response theory analyses showed poor model fit for five items identified in the Rutgers Alcohol Problem Index. Two-parameter item response theory logistic models were applied to the remaining 18 items to examine estimates of item difficulty (i.e., severity) and discrimination parameters. The item difficulty parameters ranged from 0.591 to 2.031, and the discrimination parameters ranged from 0.321 to 2.371. Classical test theory analyses indicated that the omission of the five misfit items did not significantly alter the psychometric properties of the construct. Conclusions: Findings suggest that those consequences that had greater severity and discrimination parameters may be used as screening items to identify female problem drinkers at risk for an alcohol use disorder. PMID:22051212

Proteomic analysis identifies differentially expressed proteins after red propolis treatment in Hep-2 cells.

Science.gov (United States)

Frozza, Caroline Olivieri da Silva; Ribeiro, Tanara da Silva; Gambato, Gabriela; Menti, Caroline; Moura, Sidnei; Pinto, Paulo Marcos; Staats, Charley Christian; Padilha, Francine Ferreira; Begnini, Karine Rech; de Leon, Priscila Marques Moura; Borsuk, Sibele; Savegnago, Lucielli; Dellagostin, Odir; Collares, Tiago; Seixas, Fabiana Kömmling; Henriques, João Antonio Pêgas; Roesch-Ely, Mariana

2014-01-01

Here we investigated alterations in the protein profile of Hep-2 treated with red propolis using two-dimensional electrophoresis associated to mass spectrometry and apoptotic rates of cells treated with and without red propolis extracts through TUNEL and Annexin-V assays. A total of 325 spots were manually excised from the two-dimensional gel electrophoresis and 177 proteins were identified using LC-MS-MS. Among all proteins identified that presented differential expression, most were down-regulated in presence of red propolis extract at a concentration of 120 μg/mL (IC50): GRP78, PRDX2, LDHB, VIM and TUBA1A. Only two up-regulated proteins were identified in this study in the non-cytotoxic (6 μg/mL) red propolis treated group: RPLP0 and RAD23B. TUNEL staining assay showed a markedly increase in the mid- to late-stage apoptosis of Hep-2 cells induced by red propolis at concentrations of 60 and 120 μg/mL when compared with non-treated cells. The increase of late apoptosis was confirmed by in situ Annexin-V analysis in which red propolis extract induced late apoptosis in a dose-dependent manner. The differences in tumor cell protein profiles warrant further investigations including isolation of major bioactive compounds of red propolis in different cell lines using proteomics and molecular tests to validate the protein expression here observed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Negative effects of item repetition on source memory.

Science.gov (United States)

Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K

2012-08-01

In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.

Effects of language dominance on item and order memory in free recall, serial recall and order reconstruction.

Science.gov (United States)

Francis, Wendy S; Baca, Yuzeth

2014-01-01

Spanish-English bilinguals (N = 144) performed free recall, serial recall and order reconstruction tasks in both English and Spanish. Long-term memory for both item and order information was worse in the less fluent language (L2) than in the more fluent language (L1). Item scores exhibited a stronger disadvantage for the L2 in serial recall than in free recall. Relative order scores were lower in the L2 for all three tasks, but adjusted scores for free and serial recall were equivalent across languages. Performance of English-speaking monolinguals (N = 72) was comparable to bilingual performance in the L1, except that monolinguals had higher adjusted order scores in free recall. Bilingual performance patterns in the L2 were consistent with the established effects of concurrent task performance on these memory tests, suggesting that the cognitive resources required for processing words in the L2 encroach on resources needed to commit item and order information to memory. These findings are also consistent with a model in which item memory is connected to the language system, order information is processed by separate mechanisms and attention can be allocated differentially to these two systems.

Psychometric Consequences of Subpopulation Item Parameter Drift

Science.gov (United States)

Huggins-Manley, Anne Corinne

2017-01-01

This study defines subpopulation item parameter drift (SIPD) as a change in item parameters over time that is dependent on subpopulations of examinees, and hypothesizes that the presence of SIPD in anchor items is associated with bias and/or lack of invariance in three psychometric outcomes. Results show that SIPD in anchor items is associated…

Location Indices for Ordinal Polytomous Items Based on Item Response Theory. Research Report. ETS RR-15-20

Science.gov (United States)

Ali, Usama S.; Chang, Hua-Hua; Anderson, Carolyn J.

2015-01-01

Polytomous items are typically described by multiple category-related parameters; situations, however, arise in which a single index is needed to describe an item's location along a latent trait continuum. Situations in which a single index would be needed include item selection in computerized adaptive testing or test assembly. Therefore single…

Loglinear multidimensional IRT models for polytomously scired Items

NARCIS (Netherlands)

Kelderman, Henk

1988-01-01

A loglinear item response theory (IRT) model is proposed that relates polytomously scored item responses to a multidimensional latent space. Each item may have a different response function where each item response may be explained by one or more latent traits. Item response functions may follow a

Gonad Transcriptome Analysis of the Pacific Oyster Crassostrea gigas Identifies Potential Genes Regulating the Sex Determination and Differentiation Process.

Science.gov (United States)

Yue, Chenyang; Li, Qi; Yu, Hong

2018-04-01

The Pacific oyster Crassostrea gigas is a commercially important bivalve in aquaculture worldwide. C. gigas has a fascinating sexual reproduction system consisting of dioecism, sex change, and occasional hermaphroditism, while knowledge of the molecular mechanisms of sex determination and differentiation is still limited. In this study, the transcriptomes of male and female gonads at different gametogenesis stages were characterized by RNA-seq. Hierarchical clustering based on genes differentially expressed revealed that 1269 genes were expressed specifically in female gonads and 817 genes were expressed increasingly over the course of spermatogenesis. Besides, we identified two and one gene modules related to female and male gonad development, respectively, using weighted gene correlation network analysis (WGCNA). Interestingly, GO and KEGG enrichment analysis showed that neurotransmitter-related terms were significantly enriched in genes related to ovary development, suggesting that the neurotransmitters were likely to regulate female sex differentiation. In addition, two hub genes related to testis development, lncRNA LOC105321313 and Cg-Sh3kbp1, and one hub gene related to ovary development, Cg-Malrd1-like, were firstly investigated. This study points out the role of neurotransmitter and non-coding RNA regulation during gonad development and produces lists of novel relevant candidate genes for further studies. All of these provided valuable information to understand the molecular mechanisms of C. gigas sex determination and differentiation.

48 CFR 852.214-72 - Alternate item(s).

Science.gov (United States)

2010-10-01

... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.214-72... 2008) Bids on []* will be given equal consideration along with bids on []** and any such bids received... [].** * Contracting officer will insert an alternate item that is considered acceptable. ** Contracting officer will...

Development and validation of an item response theory-based Social Responsiveness Scale short form.

Science.gov (United States)

Sturm, Alexandra; Kuhfeld, Megan; Kasari, Connie; McCracken, James T

2017-09-01

Research and practice in autism spectrum disorder (ASD) rely on quantitative measures, such as the Social Responsiveness Scale (SRS), for characterization and diagnosis. Like many ASD diagnostic measures, SRS scores are influenced by factors unrelated to ASD core features. This study further interrogates the psychometric properties of the SRS using item response theory (IRT), and demonstrates a strategy to create a psychometrically sound short form by applying IRT results. Social Responsiveness Scale analyses were conducted on a large sample (N = 21,426) of youth from four ASD databases. Items were subjected to item factor analyses and evaluation of item bias by gender, age, expressive language level, behavior problems, and nonverbal IQ. Item selection based on item psychometric properties, DIF analyses, and substantive validity produced a reduced item SRS short form that was unidimensional in structure, highly reliable (α = .96), and free of gender, age, expressive language, behavior problems, and nonverbal IQ influence. The short form also showed strong relationships with established measures of autism symptom severity (ADOS, ADI-R, Vineland). Degree of association between all measures varied as a function of expressive language. Results identified specific SRS items that are more vulnerable to non-ASD-related traits. The resultant 16-item SRS short form may possess superior psychometric properties compared to the original scale and emerge as a more precise measure of ASD core symptom severity, facilitating research and practice. Future research using IRT is needed to further refine existing measures of autism symptomatology. © 2017 Association for Child and Adolescent Mental Health.

Identifying the Viral Genes Encoding Envelope Glycoproteins for Differentiation of Cyprinid herpesvirus 3 Isolates

Directory of Open Access Journals (Sweden)

Se Chang Park

2013-01-01

Full Text Available Cyprinid herpes virus 3 (CyHV-3 diseases have been reported around the world and are associated with high mortalities of koi (Cyprinus carpio. Although little work has been conducted on the molecular analysis of this virus, glycoprotein genes identified in the present study seem to be valuable targets for genetic comparison of this virus. Three envelope glycoprotein genes (ORF25, 65 and 116 of the CyHV-3 isolates from the USA, Israel, Japan and Korea were compared, and interestingly, sequence insertions or deletions were observed in these target regions. In addition, polymorphisms were presented in microsatellite zones from two glycoprotein genes (ORF65 and 116. In phylogenetic tree analysis, the Korean isolate was remarkably distinguished from USA, Israel, Japan isolates. These findings may be suitable for many applications including isolates differentiation and phylogeny studies.

Identifying the Viral Genes Encoding Envelope Glycoproteins for Differentiation of Cyprinid herpesvirus 3 Isolates

Science.gov (United States)

Han, Jee Eun; Kim, Ji Hyung; Renault, Tristan; Choresca, Casiano; Shin, Sang Phil; Jun, Jin Woo; Park, Se Chang

2013-01-01

Cyprinid herpes virus 3 (CyHV-3) diseases have been reported around the world and are associated with high mortalities of koi (Cyprinus carpio). Although little work has been conducted on the molecular analysis of this virus, glycoprotein genes identified in the present study seem to be valuable targets for genetic comparison of this virus. Three envelope glycoprotein genes (ORF25, 65 and 116) of the CyHV-3 isolates from the USA, Israel, Japan and Korea were compared, and interestingly, sequence insertions or deletions were observed in these target regions. In addition, polymorphisms were presented in microsatellite zones from two glycoprotein genes (ORF65 and 116). In phylogenetic tree analysis, the Korean isolate was remarkably distinguished from USA, Israel, Japan isolates. These findings may be suitable for many applications including isolates differentiation and phylogeny studies. PMID:23435236

Macrostructural Treatment of Multi-word Lexical Items