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Sample records for single item assessing

  1. Assessing the Validity of Single-item Life Satisfaction Measures: Results from Three Large Samples

    Science.gov (United States)

    Cheung, Felix; Lucas, Richard E.

    2014-01-01

    Purpose The present paper assessed the validity of single-item life satisfaction measures by comparing single-item measures to the Satisfaction with Life Scale (SWLS) - a more psychometrically established measure. Methods Two large samples from Washington (N=13,064) and Oregon (N=2,277) recruited by the Behavioral Risk Factor Surveillance System (BRFSS) and a representative German sample (N=1,312) recruited by the Germany Socio-Economic Panel (GSOEP) were included in the present analyses. Single-item life satisfaction measures and the SWLS were correlated with theoretically relevant variables, such as demographics, subjective health, domain satisfaction, and affect. The correlations between the two life satisfaction measures and these variables were examined to assess the construct validity of single-item life satisfaction measures. Results Consistent across three samples, single-item life satisfaction measures demonstrated substantial degree of criterion validity with the SWLS (zero-order r = 0.62 – 0.64; disattenuated r = 0.78 – 0.80). Patterns of statistical significance for correlations with theoretically relevant variables were the same across single-item measures and the SWLS. Single-item measures did not produce systematically different correlations compared to the SWLS (average difference = 0.001 – 0.005). The average absolute difference in the magnitudes of the correlations produced by single-item measures and the SWLS were very small (average absolute difference = 0.015 −0.042). Conclusions Single-item life satisfaction measures performed very similarly compared to the multiple-item SWLS. Social scientists would get virtually identical answer to substantive questions regardless of which measure they use. PMID:24890827

  2. Assessing the validity of single-item life satisfaction measures: results from three large samples.

    Science.gov (United States)

    Cheung, Felix; Lucas, Richard E

    2014-12-01

    The present paper assessed the validity of single-item life satisfaction measures by comparing single-item measures to the Satisfaction with Life Scale (SWLS)-a more psychometrically established measure. Two large samples from Washington (N = 13,064) and Oregon (N = 2,277) recruited by the Behavioral Risk Factor Surveillance System and a representative German sample (N = 1,312) recruited by the Germany Socio-Economic Panel were included in the present analyses. Single-item life satisfaction measures and the SWLS were correlated with theoretically relevant variables, such as demographics, subjective health, domain satisfaction, and affect. The correlations between the two life satisfaction measures and these variables were examined to assess the construct validity of single-item life satisfaction measures. Consistent across three samples, single-item life satisfaction measures demonstrated substantial degree of criterion validity with the SWLS (zero-order r = 0.62-0.64; disattenuated r = 0.78-0.80). Patterns of statistical significance for correlations with theoretically relevant variables were the same across single-item measures and the SWLS. Single-item measures did not produce systematically different correlations compared to the SWLS (average difference = 0.001-0.005). The average absolute difference in the magnitudes of the correlations produced by single-item measures and the SWLS was very small (average absolute difference = 0.015-0.042). Single-item life satisfaction measures performed very similarly compared to the multiple-item SWLS. Social scientists would get virtually identical answer to substantive questions regardless of which measure they use.

  3. Single Item Inventory Models

    NARCIS (Netherlands)

    E.M. Bazsa-Oldenkamp; P. den Iseger

    2001-01-01

    textabstractThis paper extends a fundamental result about single-item inventory systems. This approach allows more general performance measures, demand processes and order policies, and leads to easier analysis and implementation, than prior research. We obtain closed form expressions for the

  4. Single item measures of emotional exhaustion and depersonalization are useful for assessing burnout in medical professionals.

    Science.gov (United States)

    West, Colin P; Dyrbye, Liselotte N; Sloan, Jeff A; Shanafelt, Tait D

    2009-12-01

    Burnout has negative effects on work performance and patient care. The current standard for burnout assessment is the Maslach Burnout Inventory (MBI), a well-validated instrument consisting of 22 items answered on a 7-point Likert scale. However, the length of the MBI can limit its utility in physician surveys. To evaluate the performance of two questions relative to the full MBI for measuring burnout. Cross-sectional data from 2,248 medical students, 333 internal medicine residents, 465 internal medicine faculty, and 7,905 practicing surgeons. The single questions with the highest factor loading on the emotional exhaustion (EE) ("I feel burned out from my work") and depersonalization (DP) ("I have become more callous toward people since I took this job") domains of burnout were evaluated in four large samples of medical students, internal medicine residents, internal medicine faculty, and practicing surgeons. Spearman correlations between the single EE question and the full EE domain score minus that question ranged from 0.76-0.83. Spearman correlations between the single DP question and the full DP domain score minus that question ranged from 0.61-0.72. Responses to the single item measures of emotional exhaustion and depersonalization stratified risk of high burnout in the relevant domain on the full MBI, with consistent patterns across the four sampled groups. Single item measures of emotional exhaustion and depersonalization provide meaningful information on burnout in medical professionals.

  5. Concurrent validity of single-item measures of emotional exhaustion and depersonalization in burnout assessment.

    Science.gov (United States)

    West, Colin P; Dyrbye, Liselotte N; Satele, Daniel V; Sloan, Jeff A; Shanafelt, Tait D

    2012-11-01

    Burnout is a common problem among physicians and physicians-in-training. The Maslach Burnout Inventory (MBI) is the gold standard for burnout assessment, but the length of this well-validated 22-item instrument can limit its feasibility for survey research. To evaluate the concurrent validity of two questions relative to the full MBI for measuring the association of burnout with published outcomes. DESIGN, PARTICIPANTS, AND MAIN MEASURES: The single questions "I feel burned out from my work" and "I have become more callous toward people since I took this job," representing the emotional exhaustion and depersonalization domains of burnout, respectively, were evaluated in published studies of medical students, internal medicine residents, and practicing surgeons. We compared predictive models for the association of each question, versus the full MBI, using longitudinal data on burnout and suicidality from 2006 and 2007 for 858 medical students at five United States medical schools, cross-sectional data on burnout and serious thoughts of dropping out of medical school from 2007 for 2222 medical students at seven United States medical schools, and cross-sectional data on burnout and unprofessional attitudes and behaviors from 2009 for 2566 medical students at seven United States medical schools. We also assessed results for longitudinal data on burnout and perceived major medical errors from 2003 to 2009 for 321 Mayo Clinic Rochester internal medicine residents and cross-sectional data on burnout and both perceived major medical errors and suicidality from 2008 for 7,905 respondents to a national survey of members of the American College of Surgeons. Point estimates of effect for models based on the single-item measures were uniformly consistent with those reported for models based on the full MBI. The single-item measures of emotional exhaustion and depersonalization exhibited strong associations with each published outcome (all p ≤ 0.008). No conclusion regarding

  6. Single-item measure for assessing quality of life in children with drug-resistant epilepsy.

    Science.gov (United States)

    Conway, Lauryn; Widjaja, Elysa; Smith, Mary Lou

    2018-03-01

    The current study investigated the psychometric properties of a single-item quality of life (QOL) measure, the Global Quality of Life in Childhood Epilepsy question (G-QOLCE), in children with drug-resistant epilepsy. Data came from the Impact of Pediatric Epilepsy Surgery on Health-Related Quality of Life Study (PESQOL), a multicenter prospective cohort study (n = 118) with observations collected at baseline and at 6 months of follow-up on children aged 4-18 years. QOL was measured with the QOLCE-76 and KIDSCREEN-27. The G-QOLCE was an overall QOL question derived from the QOLCE-76. Construct validity and reliability were assessed with Spearman's correlation and intraclass correlation coefficient (ICC). Responsiveness was examined through distribution-based and anchor-based methods. The G-QOLCE showed moderate (r ≥ 0.30) to strong (r ≥ 0.50) correlations with composite scores, and most subscales of the QOLCE-76 and KIDSCREEN-27 at baseline and 6-month follow-up. The G-QOLCE had moderate test-retest reliability (ICC range: 0.49-0.72) and was able to detect clinically important change in patients' QOL (standardized response mean: 0.38; probability of change: 0.65; Guyatt's responsiveness statistics: 0.62 and 0.78). Caregiver anxiety and family functioning contributed most strongly to G-QOLCE scores over time. Results offer promising preliminary evidence regarding the validity, reliability, and responsiveness of the proposed single-item QOL measure. The G-QOLCE is a potentially useful tool that can be feasibly administered in a busy clinical setting to evaluate clinical status and impact of treatment outcomes in pediatric epilepsy.

  7. Assessment of Fatigue in Rheumatoid Arthritis: A Psychometric Comparison of Single-item, Multiitem, and Multidimensional Measures

    NARCIS (Netherlands)

    Oude Voshaar, M.A.H.; Klooster, P.M. ten; Bode, C.; Vonkeman, H.E.; Glas, C.A.; Jansen, T.L.Th.A.; Albada-Kuipers, I. van; Riel, P.L.C.M. van; Laar, M.A. van der

    2015-01-01

    OBJECTIVE: To compare the psychometric functioning of multidimensional disease-specific, multiitem generic, and single-item measures of fatigue in patients with rheumatoid arthritis (RA). METHODS: Confirmatory factor analysis (CFA) and longitudinal item response theory (IRT) modeling were used to

  8. Assessment of fatigue in rheumatoid arthritis: a psychometric comparison of single-item, multiitem, and multidimensional measures

    NARCIS (Netherlands)

    Oude Voshaar, Antonius H.; ten Klooster, Peter M.; Bode, Christina; Vonkeman, Harald Erwin; Glas, Cornelis A.W.; Jansen, Tim; van Albeda-Kuijpers, Iet; van Riel, Piet L.C.M.; van de Laar, Mart A F J

    2015-01-01

    OBJECTIVE: To compare the psychometric functioning of multidimensional disease-specific, multiitem generic, and single-item measures of fatigue in patients with rheumatoid arthritis (RA). METHODS: Confirmatory factor analysis (CFA) and longitudinal item response theory (IRT) modeling were used to

  9. The Feasibility of Single-Item Measures for Organizational Justice

    Science.gov (United States)

    Jordan, Jeremy S.; Turner, Brian A.

    2008-01-01

    Researchers in a number of disciplines have examined the utility of single-item measures for both affective and cognitive constructs. While these authors have indicated that, under certain circumstances, the use of single-item measures is appropriate, there remains concern regarding the reliability and validity of single-item measures. This study…

  10. Meta-analytic guidelines for evaluating single-item reliabilities of personality instruments.

    Science.gov (United States)

    Spörrle, Matthias; Bekk, Magdalena

    2014-06-01

    Personality is an important predictor of various outcomes in many social science disciplines. However, when personality traits are not the principal focus of research, for example, in global comparative surveys, it is often not possible to assess them extensively. In this article, we first provide an overview of the advantages and challenges of single-item measures of personality, a rationale for their construction, and a summary of alternative ways of assessing their reliability. Second, using seven diverse samples (Ntotal = 4,263) we develop the SIMP-G, the German adaptation of the Single-Item Measures of Personality, an instrument assessing the Big Five with one item per trait, and evaluate its validity and reliability. Third, we integrate previous research and our data into a first meta-analysis of single-item reliabilities of personality measures, and provide researchers with guidelines and recommendations for the evaluation of single-item reliabilities. © The Author(s) 2013.

  11. Assessing the Item Response Theory with Covariate (IRT-C) Procedure for Ascertaining Differential Item Functioning

    Science.gov (United States)

    Tay, Louis; Vermunt, Jeroen K.; Wang, Chun

    2013-01-01

    We evaluate the item response theory with covariates (IRT-C) procedure for assessing differential item functioning (DIF) without preknowledge of anchor items (Tay, Newman, & Vermunt, 2011). This procedure begins with a fully constrained baseline model, and candidate items are tested for uniform and/or nonuniform DIF using the Wald statistic.…

  12. Correlates of a Single-Item Indicator Versus a Multi-Item Scale of Outness About Same-Sex Attraction.

    Science.gov (United States)

    Wilkerson, J Michael; Noor, Syed W; Galos, Dylan L; Rosser, B R Simon

    2016-07-01

    In this study, we investigated if a single-item indicator measured the degree to which people were open about their same-sex attraction ("out") as accurately as a multi-item scale. For the multi-item scale, we used the Outness Inventory, which includes three subscales: family, world, and religion. We examined correlations between the single- and multi-item measures; between the single-item indicator and the subscales of the multi-item scale; and between the measures and internalized homonegativity, social attitudes towards homosexuality, and depressive symptoms. In addition, we calculated Tjur's R (2) as a measure of predictive power of the single-item indicator, multi-item scale, and subscales of the multi-item scale in predicting two health-related outcomes: depressive symptoms and condomless anal sex with multiple partners. There was a strong correlation between the single- and multi-item measures (r = 0.73). Furthermore, there were strong correlations between the single-item indicator and each subscale of the multi-item scale: family (r = 0.70), world (r = 0.77), and religion (r = 0.50). In addition, the correlations between the single-item indicator and internalized homonegativity (r = -0.63), social attitudes towards homosexuality (r = -0.38), and depression (r = -0.14) were higher than those between the multi-item scale and internalized homonegativity (r = -0.55), social attitudes towards homosexuality (r = -0.21), and depression (r = -0.13). Contrary to the premise that multi-item measures are superior to single-item measures, our collective findings indicate that the single-item indicator of outness performs better than the multi-item scale of outness.

  13. Single-Item Measurement of Suicidal Behaviors: Validity and Consequences of Misclassification.

    Directory of Open Access Journals (Sweden)

    Alexander J Millner

    Full Text Available Suicide is a leading cause of death worldwide. Although research has made strides in better defining suicidal behaviors, there has been less focus on accurate measurement. Currently, the widespread use of self-report, single-item questions to assess suicide ideation, plans and attempts may contribute to measurement problems and misclassification. We examined the validity of single-item measurement and the potential for statistical errors. Over 1,500 participants completed an online survey containing single-item questions regarding a history of suicidal behaviors, followed by questions with more precise language, multiple response options and narrative responses to examine the validity of single-item questions. We also conducted simulations to test whether common statistical tests are robust against the degree of misclassification produced by the use of single-items. We found that 11.3% of participants that endorsed a single-item suicide attempt measure engaged in behavior that would not meet the standard definition of a suicide attempt. Similarly, 8.8% of those who endorsed a single-item measure of suicide ideation endorsed thoughts that would not meet standard definitions of suicide ideation. Statistical simulations revealed that this level of misclassification substantially decreases statistical power and increases the likelihood of false conclusions from statistical tests. Providing a wider range of response options for each item reduced the misclassification rate by approximately half. Overall, the use of single-item, self-report questions to assess the presence of suicidal behaviors leads to misclassification, increasing the likelihood of statistical decision errors. Improving the measurement of suicidal behaviors is critical to increase understanding and prevention of suicide.

  14. Single item inventory models : A time- and event- averages approach

    NARCIS (Netherlands)

    E.M. Bazsa-Oldenkamp; P. den Iseger

    2003-01-01

    textabstractThis paper extends a fundamental result about single-item inventory systems. This approach allows more general performance measures, demand processes and order policies, and leads to easier analysis and implementation, than prior research. We obtain closed form expressions for the

  15. Face validity of the single work ability item

    DEFF Research Database (Denmark)

    Gupta, Nidhi; Jensen, Bjørn Søvsø; Søgaard, Karen

    2014-01-01

    PURPOSE: The purpose of this study was to investigate the face validity of the self-reported single item work ability with objectively measured heart rate reserve (%HRR) among blue-collar workers. METHODS: We utilized data from 127 blue-collar workers (Female = 53; Male = 74) aged 18-65 years fro...

  16. Single-item memory, associative memory, and the human hippocampus

    OpenAIRE

    Gold, Jeffrey J.; Hopkins, Ramona O.; Squire, Larry R.

    2006-01-01

    We tested recognition memory for items and associations in memory-impaired patients with bilateral lesions thought to be limited to the hippocampal region. In Experiment 1 (Combined memory test), participants studied words and then took a memory test in which studied words, new words, studied word pairs, and recombined word pairs were presented in a mixed order. In Experiment 2 (Separated memory test), participants studied single words and then took a memory test involving studied word and ne...

  17. Assessing the factor structure of a role functioning item bank.

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    Anatchkova, Milena D; Ware, John E; Bjorner, Jakob B

    2011-06-01

    Role functioning (RF) is an important part of health-related quality of life, but is hard to measure due to the wide definition of roles and fluctuations in role participation. This study aims to explore the dimensionality of a newly developed item bank assessing the impact of health on RF. A battery of measures with skip patterns including the new RF bank was completed by 2,500 participants answering only questions on social roles relevant to them. Confirmatory factor analyses were conducted for the participants answering items from all conceptual domains (N = 1193). Conceptually based dimensionality and method effects reflecting positively and negatively worded items were explored in a series of models. A bi-factor model (CFI = .93, RMSEA = .08) with one general and four conceptual factors (social, family, occupation, generic) was retained. Positively worded items were excluded from the final solution due to misfit. While a single factor model with methods factors had a poor fit (CFI = .88, RMSEA = .13), high loadings on the general factor in the bi-factor model suggest that the RF bank is sufficiently unidimensional for IRT analysis. The bank demonstrated sufficient unidimensionality for IRT-based calibration of all the items on a common metric and development of a computerized adaptive test.

  18. Assessing difference between classical test theory and item ...

    African Journals Online (AJOL)

    Assessing difference between classical test theory and item response theory methods in scoring primary four multiple choice objective test items. ... All research participants were ranked on the CTT number correct scores and the corresponding IRT item pattern scores from their performance on the PRISMADAT. Wilcoxon ...

  19. Development and validation of the Single Item Narcissism Scale (SINS).

    Science.gov (United States)

    Konrath, Sara; Meier, Brian P; Bushman, Brad J

    2014-01-01

    The narcissistic personality is characterized by grandiosity, entitlement, and low empathy. This paper describes the development and validation of the Single Item Narcissism Scale (SINS). Although the use of longer instruments is superior in most circumstances, we recommend the SINS in some circumstances (e.g. under serious time constraints, online studies). In 11 independent studies (total N = 2,250), we demonstrate the SINS' psychometric properties. The SINS is significantly correlated with longer narcissism scales, but uncorrelated with self-esteem. It also has high test-retest reliability. We validate the SINS in a variety of samples (e.g., undergraduates, nationally representative adults), intrapersonal correlates (e.g., positive affect, depression), and interpersonal correlates (e.g., aggression, relationship quality, prosocial behavior). The SINS taps into the more fragile and less desirable components of narcissism. The SINS can be a useful tool for researchers, especially when it is important to measure narcissism with constraints preventing the use of longer measures.

  20. A Model-Free Diagnostic for Single-Peakedness of Item Responses Using Ordered Conditional Means

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    Polak, Marike; De Rooij, Mark; Heiser, Willem J.

    2012-01-01

    In this article we propose a model-free diagnostic for single-peakedness (unimodality) of item responses. Presuming a unidimensional unfolding scale and a given item ordering, we approximate item response functions of all items based on ordered conditional means (OCM). The proposed OCM methodology is based on Thurstone & Chave's (1929) "criterion…

  1. Development and validation of the Single Item Narcissism Scale (SINS.

    Directory of Open Access Journals (Sweden)

    Sara Konrath

    Full Text Available MAIN OBJECTIVES: The narcissistic personality is characterized by grandiosity, entitlement, and low empathy. This paper describes the development and validation of the Single Item Narcissism Scale (SINS. Although the use of longer instruments is superior in most circumstances, we recommend the SINS in some circumstances (e.g. under serious time constraints, online studies. METHODS: In 11 independent studies (total N = 2,250, we demonstrate the SINS' psychometric properties. RESULTS: The SINS is significantly correlated with longer narcissism scales, but uncorrelated with self-esteem. It also has high test-retest reliability. We validate the SINS in a variety of samples (e.g., undergraduates, nationally representative adults, intrapersonal correlates (e.g., positive affect, depression, and interpersonal correlates (e.g., aggression, relationship quality, prosocial behavior. The SINS taps into the more fragile and less desirable components of narcissism. SIGNIFICANCE: The SINS can be a useful tool for researchers, especially when it is important to measure narcissism with constraints preventing the use of longer measures.

  2. Separation index and fit items of creative thinking skills assessment

    Directory of Open Access Journals (Sweden)

    Andi Ulfa Tenri Pada

    2016-06-01

    Full Text Available This article discusses the evaluation results of the separation index and fit item of creative thinking skills assessment that supports the conation aspect of prospective biology teachers in Aceh. This assessment consists of 37 items of divergent tasks, which is the application of human physiology courses that support the conation aspects. The participants were selected from the Biology Education Program, Faculty of Teacher Training and Education, Syiah Kuala University. The data were analyzed using the Quest software including the separation index and fit item. The results indicate that the creative thinking skills assessment instrument that supports the conation aspect of prospective biology teachers has a good separation index and all the items fit PCM-1PL.

  3. Which single-item measures of overactive bladder symptom treatment correlate best with patient satisfaction?

    Science.gov (United States)

    Michel, Martin C; Oelke, Matthias; Vogel, Monika; de la Rosette, Jean J M C H

    2011-04-01

    While complex symptom scales are important research tools, simpler, preferably single item scales may be more useful for routine clinical practise in the evaluation of patients with overactive bladder syndrome (OAB). This study aimed to compare multiple single-item scales at baseline and after treatment with patient-reported overall rating of treatment efficacy. In a pre-planned secondary analysis of a previously reported observational study, 4,450 patients were evaluated at baseline and after 12 weeks open-label treatment with solifenacin. Apart from episode counting for classical OAB symptoms, the following single-item rating scales were applied: Indevus Urgency Severity Scale, Urgency Perception Scale, a Visual Analog Scale (VAS), quality of life question of the IPSS, and general health and bladder problem questions of the King's Health Questionnaire (KHQ). At baseline OAB symptoms correlated at best moderately with each (r = 0.285-0.508) other or with any of the rating scales (r = 0.060-0.399). Pair-wise correlations between treatment-associated symptom or scale improvements tended to be tighter (r = 0.225-0.588). When compared to patient-reported efficacy, the VAS (r = 0.487) and the bladder problem question of the KHQ (r = 0.452) showed the tightest correlation, whereas all symptom and rating scale improvements exhibited poor correlation with patient-reported tolerability (r ≤ 0.283). The VAS and the bladder problem question of the KHQ show the greatest promise as single-item scales to assess problem intensity in OAB patients. Copyright © 2011 Wiley-Liss, Inc.

  4. Which Single-Item Measures of Overactive Bladder Symptom Treatment Correlate Best With Patient Satisfaction?

    NARCIS (Netherlands)

    Michel, Martin C.; Oelke, Matthias; Vogel, Monika; de La Rosette, Jean J. M. C. H.

    2011-01-01

    Aims: While complex symptom scales are important research tools, simpler, preferably single item scales may be more useful for routine clinical practise in the evaluation of patients with overactive bladder syndrome (OAB). This study aimed to compare multiple single-item scales at baseline and after

  5. 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.

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

    Science.gov (United States)

    Luciano, Juan V; Ayuso-Mateos, José L; Aguado, Jaume; Fernandez, Ana; Serrano-Blanco, Antoni; Roca, Miquel; Haro, Josep M

    2010-05-20

    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. 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. 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. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Assessing Differential Item Functioning on the Test of Relational Reasoning

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    Denis Dumas

    2018-03-01

    Full Text Available The test of relational reasoning (TORR is designed to assess the ability to identify complex patterns within visuospatial stimuli. The TORR is designed for use in school and university settings, and therefore, its measurement invariance across diverse groups is critical. In this investigation, a large sample, representative of a major university on key demographic variables, was collected, and the resulting data were analyzed using a multi-group, multidimensional item-response theory model-comparison procedure. No significant differential item functioning was found on any of the TORR items across any of the demographic groups of interest. This finding is interpreted as evidence of the cultural fairness of the TORR, and potential test-development choices that may have contributed to that cultural fairness are discussed.

  9. Item reduction and psychometric validation of the Oily Skin Self Assessment Scale (OSSAS) and the Oily Skin Impact Scale (OSIS).

    Science.gov (United States)

    Arbuckle, Robert; Clark, Marci; Harness, Jane; Bonner, Nicola; Scott, Jane; Draelos, Zoe; Rizer, Ronald; Yeh, Yating; Copley-Merriman, Kati

    2009-01-01

    Developed using focus groups, the Oily Skin Self Assessment Scale (OSSAS) and Oily Skin Impact Scale (OSIS) are patient-reported outcome measures of oily facial skin. The aim of this study was to finalize the item-scale structure of the instruments and perform psychometric validation in adults with self-reported oily facial skin. The OSSAS and OSIS were administered to 202 adult subjects with oily facial skin in the United States. A subgroup of 152 subjects returned, 4 to 10 days later, for test–retest reliability evaluation. Of the 202 participants, 72.8% were female; 64.4% had self-reported nonsevere acne. Item reduction resulted in a 14-item OSSAS with Sensation (five items), Tactile (four items) and Visual (four items) domains, a single blotting item, and an overall oiliness item. The OSIS was reduced to two three-item domains assessing Annoyance and Self-Image. Confirmatory factor analysis supported the construct validity of the final item-scale structures. The OSSAS and OSIS scales had acceptable item convergent validity (item-scale correlations >0.40) and floor and ceiling effects (skin severity (P skin (P skin), as assessments of self-reported oily facial skin severity and its emotional impact, respectively.

  10. Item Response Theory with Covariates (IRT-C) : Assessing item recovery and differential item functioning for the three-parameter logistic model

    NARCIS (Netherlands)

    Tay, L.; Huang, Q.; Vermunt, J.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

  11. Cross-National Prevalence of Traditional Bullying, Traditional Victimization, Cyberbullying and Cyber-Victimization: Comparing Single-Item and Multiple-Item Approaches of Measurement

    Science.gov (United States)

    Yanagida, Takuya; Gradinger, Petra; Strohmeier, Dagmar; Solomontos-Kountouri, Olga; Trip, Simona; Bora, Carmen

    2016-01-01

    Many large-scale cross-national studies rely on a single-item measurement when comparing prevalence rates of traditional bullying, traditional victimization, cyberbullying, and cyber-victimization between countries. However, the reliability and validity of single-item measurement approaches are highly problematic and might be biased. Data from…

  12. Evaluate the continuity of meeting items requirements when assessing buildings

    Directory of Open Access Journals (Sweden)

    Amal Kamal Mohamed Shamseldin

    2017-08-01

    Full Text Available Green architecture emerged as a way to address environmental problems related to buildings. Various methods have been developed to assess environmental performance, such as LEED in the United States, BREEAM in the United Kingdom, and GPRS in Egypt. The accuracy of these methods is highly important, especially considering the global trend toward requiring proof of environmental efficiency for construction permits. However, obtaining accurate results requires taking into account the variables that affect the environmental assessment. These variables include the impact of natural and human changes that occur periodically (the repetition of certain events according to day, month, and year, sequentially (changes over time, and suddenly (disasters and other unexpected events. These relationships are not addressed in current assessment methods. Since assessment has several targets, including developing a system to compare buildings according to a specific, unified scale, designers must compete to meet environmental standards based on a fair comparison; thus, the treatment of several variable effects must be obtained to reach those goals. This study, therefore, proposes an approach for considering the effects of variables when assessing item requirements. By measuring the continuity of meeting the item requirements across different time periods, this approach can achieve higher accuracy and justice in evaluation results than afforded by current methods.

  13. Diagnostic Assessment With Ordered Multiple-Choice Items

    Science.gov (United States)

    Briggs, Derek C.; Alonzo, Alicia C.; Schwab, Cheryl; Wilson, Mark

    2006-01-01

    In this article we describe the development, analysis, and interpretation of a novel item format we call Ordered Multiple-Choice (OMC). A unique feature of OMC items is that they are linked to a model of student cognitive development for the construct being measured. Each of the possible answer choices in an OMC item is linked to developmental…

  14. Missouri Assessment Program (MAP), Spring 2000: Secondary Science, Released Items, Grade 10.

    Science.gov (United States)

    Missouri State Dept. of Elementary and Secondary Education, Jefferson City.

    This assessment sample provides information on the Missouri Assessment Program (MAP) for grade 10 science. The sample consists of six items taken from the test booklet and scoring guides for the six items. The items assess ecosystems, mechanics, and data analysis. (MM)

  15. Fully Polynomial Approximation Schemes for Single-Item Capacitated Economic Lot-Sizing Problems

    NARCIS (Netherlands)

    C.P.M. van Hoesel; A.P.M. Wagelmans (Albert)

    1997-01-01

    textabstractNP-hard cases of the single-item capacitated lot-sizing problem have been the topic of extensive research and continue to receive considerable attention. However, surprisingly few theoretical results have been published on approximation methods for these problems. To the best of our

  16. Assessing Acquiescence in Binary Responses: IRT-Related Item-Factor-Analytic Procedures

    Science.gov (United States)

    Ferrando, Pere J.; Condon, Lorena

    2006-01-01

    This article proposes procedures for assessing acquiescence in a balanced set of binary personality items. These procedures are based on the bidimensional item-factor analysis model, which is an alternative parameterization of the bidimensional 2-parameter normal-ogive item response theory model. First the rationale and general approach are…

  17. The Use of Hierarchical Generalized Linear Model for Item Dimensionality Assessment

    Science.gov (United States)

    Beretvas, S. Natasha; Williams, Natasha J.

    2004-01-01

    To assess item dimensionality, the following two approaches are described and compared: hierarchical generalized linear model (HGLM) and multidimensional item response theory (MIRT) model. Two generating models are used to simulate dichotomous responses to a 17-item test: the unidimensional and compensatory two-dimensional (C2D) models. For C2D…

  18. The DIF-Free-Then-DIF Strategy for the Assessment of Differential Item Functioning

    Science.gov (United States)

    Wang, Wen-Chung; Shih, Ching-Lin; Sun, Guo-Wei

    2012-01-01

    The DIF-free-then-DIF (DFTD) strategy consists of two steps: (a) select a set of items that are the most likely to be DIF-free and (b) assess the other items for DIF (differential item functioning) using the designated items as anchors. The rank-based method together with the computer software IRTLRDIF can select a set of DIF-free polytomous items…

  19. Reading Grade Levels and Mathematics Assessment: An Analysis of Texas Mathematics Assessment Items and Their Reading Difficulty

    Science.gov (United States)

    Lamb, John H.

    2010-01-01

    Increased reading difficulty of mathematics assessment items has been shown to negatively affect student performance. The advent of high-stakes testing, which has serious ramifications for students' futures and teachers' careers, necessitates analysis of reading difficulty on state assessment items and student performance on those items. Using…

  20. Using personality item characteristics to predict single-item reliability, retest reliability, and self-other agreement

    NARCIS (Netherlands)

    de Vries, Reinout Everhard; Realo, Anu; Allik, Jüri

    2016-01-01

    The use of reliability estimates is increasingly scrutinized as scholars become more aware that test–retest stability and self–other agreement provide a better approximation of the theoretical and practical usefulness of an instrument than its internal reliability. In this study, we investigate item

  1. A mathematical model for order splitting in a multiple supplier single-item inventory system

    DEFF Research Database (Denmark)

    Abginehchi, Soheil; Farahani, Reza Zanjirani; Rezapour, Shabnam

    2013-01-01

    The policy of simultaneously splitting replenishment orders among several suppliers has received considerable attention in the last few years and continues to attract the attention of researchers. In this paper, we develop a mathematical model which considers multiple-supplier single-item inventory...... systems. The item acquisition lead times of suppliers are random variables. Backorder is allowed and shortage cost is charged based on not only per unit in shortage but also per time unit. Continuous review (s,Q) policy has been assumed. When the inventory level depletes to a reorder level, the total......, procurement cost, inventory holding cost, and shortage cost, is minimized. We also conduct extensive numerical experiments to show the advantages of our model compared with the models in the literature. According to our extensive experiments, the model developed in this paper is the best model...

  2. Comparison of classical test theory and item response theory in individual change assessment

    NARCIS (Netherlands)

    Jabrayilov, R.; Emons, W.H.M.; Sijtsma, K.

    2016-01-01

    Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. Individual change assessment can be conducted using either the methodologies of classical test theory (CTT) or item response theory (IRT). Researchers have been optimistic

  3. Comparison of Classical Test Theory and Item Response Theory in Individual Change Assessment

    NARCIS (Netherlands)

    Jabrayilov, Ruslan; Emons, Wilco H. M.; Sijtsma, Klaas

    2016-01-01

    Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. Individual change assessment can be conducted using either the methodologies of classical test theory (CTT) or item response theory (IRT). Researchers have been optimistic

  4. Weighted Association Rule Mining for Item Groups with Different Properties and Risk Assessment for Networked Systems

    Science.gov (United States)

    Kim, Jungja; Ceong, Heetaek; Won, Yonggwan

    In market-basket analysis, weighted association rule (WAR) discovery can mine the rules that include more beneficial information by reflecting item importance for special products. In the point-of-sale database, each transaction is composed of items with similar properties, and item weights are pre-defined and fixed by a factor such as the profit. However, when items are divided into more than one group and the item importance must be measured independently for each group, traditional weighted association rule discovery cannot be used. To solve this problem, we propose a new weighted association rule mining methodology. The items should be first divided into subgroups according to their properties, and the item importance, i.e. item weight, is defined or calculated only with the items included in the subgroup. Then, transaction weight is measured by appropriately summing the item weights from each subgroup, and the weighted support is computed as the fraction of the transaction weights that contains the candidate items relative to the weight of all transactions. As an example, our proposed methodology is applied to assess the vulnerability to threats of computer systems that provide networked services. Our algorithm provides both quantitative risk-level values and qualitative risk rules for the security assessment of networked computer systems using WAR discovery. Also, it can be widely used for new applications with many data sets in which the data items are distinctly separated.

  5. Validity of a single item food security questionnaire in Arctic Canada.

    Science.gov (United States)

    Urke, Helga Bjørnøy; Cao, Zhirong R; Egeland, Grace M

    2014-06-01

    Assess sensitivity and specificity of each of the 18 US Department of Agriculture (USDA) Household Food Security Scale Module (HFSSM) questionnaire items to determine whether a rapid assessment of child and adult food insecurity is feasible in an Inuit population. Food insecurity prevalence was assessed by the 18-item USDA HFSSM in a randomized sample of Inuit households participating in the Inuit Health Survey and the Nunavut Inuit Child Health Survey. Questions were evaluated for sensitivity, specificity, predictive value (+/2), and total percent accuracy for adult and child food insecurity (yes/no). Child food security items were evaluated for both surveys. For children, the question “In the last 12 months, were there times when it was not possible to feed the children a healthy meal because there was not enough money?” had the best performance in both samples with a sensitivity and specificity of 92.3% and 97.3%, respectively, for the Inuit Health Survey, and 88.5% and 95.4% for the Nunavut Inuit Child Health Survey. For adults, the question “In the last 12 months, were there times when the food for you and your family just did not last and there was no money to buy more?” demonstrated a sensitivity of 93.0% and a specificity of 93.4%. Rapid assessment of child and adult food insecurity is feasible and may be a useful tool for health care and social service providers. However, as prevalence and severity of food insecurity change over time, rapid assessment techniques should not replace periodic screening by using the full USDA HFSSM questionnaire.

  6. The development and validation of a novel outcome measure to quantify mobility in the dysvascular lower extremity amputee: the amputee single item mobility measure

    Science.gov (United States)

    Norvell, Daniel C; Williams, Rhonda M; Turner, Aaron P; Czerniecki, Joseph M

    2016-01-01

    Objective: This study describes the development and psychometric evaluation of a novel patient-reported single-item mobility measure. Design: Prospective cohort study. Setting: Four Veteran’s Administration Medical Centers. Subjects: Individuals undergoing their first major unilateral lower extremity amputation; 198 met inclusion criteria; of these, 113 (57%) enrolled. Interventions: None. Main measures: The Amputee Single Item Mobility Measure, a single item measure with scores ranging from 0 to 6, was developed by an expert panel, and concurrently administered with the Locomotor Capabilities Index-5 (LCI-5) and other outcome measures at six weeks, four months, and 12 months post-amputation. Criterion and construct validity, responsiveness, and floor/ceiling effects were evaluated. Responsiveness was assessed using the standardized response mean. Results: The overall mean 12-month Amputee Single Item Mobility Measure score was 3.39 ±1.4. Scores for transmetatarsal, transtibial, and transfemoral amputees were 4.2 (±1.3), 3.2 (±1.5), and 2.9 (±1.1), respectively. Amputee Single Item Mobility Measure scores demonstrated “large” and statistically significant correlations with the LCI-5 scores at six weeks (r = 0.72), four months (r = 0.81), and 12 months (r = 0.86). At four months and 12 months, the correlation between Amputee Single Item Mobility Measure scores and hours of prosthetic use were r = 0.69 and r = 0.66, respectively, and between Amputee Single Item Mobility Measure scores and Trinity Amputation and Prosthesis Experience Scales functional restriction scores were r = 0.45 and r = 0.67, respectively. Amputee Single Item Mobility Measure scores increased significantly from six weeks to 12 months post-amputation. Minimal floor/ceiling effects were demonstrated. Conclusions: In the unilateral dysvascular amputee, the Amputee Single Item Mobility Measure has strong criterion and construct validity, excellent

  7. Assessment of the Item Selection and Weighting in the Birmingham Vasculitis Activity Score for Wegener's Granulomatosis

    Science.gov (United States)

    MAHR, ALFRED D.; NEOGI, TUHINA; LAVALLEY, MICHAEL P.; DAVIS, JOHN C.; HOFFMAN, GARY S.; MCCUNE, W. JOSEPH; SPECKS, ULRICH; SPIERA, ROBERT F.; ST.CLAIR, E. WILLIAM; STONE, JOHN H.; MERKEL, PETER A.

    2013-01-01

    Objective To assess the Birmingham Vasculitis Activity Score for Wegener's Granulomatosis (BVAS/WG) with respect to its selection and weighting of items. Methods This study used the BVAS/WG data from the Wegener's Granulomatosis Etanercept Trial. The scoring frequencies of the 34 predefined items and any “other” items added by clinicians were calculated. Using linear regression with generalized estimating equations in which the physician global assessment (PGA) of disease activity was the dependent variable, we computed weights for all predefined items. We also created variables for clinical manifestations frequently added as other items, and computed weights for these as well. We searched for the model that included the items and their generated weights yielding an activity score with the highest R2 to predict the PGA. Results We analyzed 2,044 BVAS/WG assessments from 180 patients; 734 assessments were scored during active disease. The highest R2 with the PGA was obtained by scoring WG activity based on the following items: the 25 predefined items rated on ≥5 visits, the 2 newly created fatigue and weight loss variables, the remaining minor other and major other items, and a variable that signified whether new or worse items were present at a specific visit. The weights assigned to the items ranged from 1 to 21. Compared with the original BVAS/WG, this modified score correlated significantly more strongly with the PGA. Conclusion This study suggests possibilities to enhance the item selection and weighting of the BVAS/WG. These changes may increase this instrument's ability to capture the continuum of disease activity in WG. PMID:18512722

  8. An instrument to assess quality of life in relation to nutrition: item generation, item reduction and initial validation

    Directory of Open Access Journals (Sweden)

    Akl Elie A

    2010-03-01

    Full Text Available Abstract Background It is arguable that modification of diet, given its potential for positive health outcomes, should be widely advocated and adopted. However, food intake, as a basic human need, and its modification may be accompanied by sensations of both pleasure and despondency and may consequently affect to quality of life (QoL. Thus, the feasibility and success of dietary changes will depend, at least partly, on whether potential negative influences on QoL can be avoided. This is of particular importance in the context of dietary intervention studies and in the development of new food products to improve health and well being. Instruments to measure the impact of nutrition on quality of life in the general population, however, are few and far between. Therefore, the aim of this project was to develop an instrument for measuring QoL related to nutrition in the general population. Methods and results We recruited participants from the general population and followed standard methodology for quality of life instrument development (identification of population, item selection, n = 24; item reduction, n = 81; item presentation, n = 12; pretesting of questionnaire and initial validation, n = 2576; construct validation n = 128; and test-retest reliability n = 20. Of 187 initial items, 29 were selected for final presentation. Factor analysis revealed an instrument with 5 domains. The instrument demonstrated good cross-sectional divergent and convergent construct validity when correlated with scores of the 8 domains of the SF-36 (ranging from -0.078 to 0.562, 19 out of 40 tested correlations were statistically significant and 24 correlations were predicted correctly and good test-retest reliability (intra-class correlation coefficients from 0.71 for symptoms to 0.90. Conclusions We developed and validated an instrument with 29 items across 5 domains to assess quality of life related to nutrition and other aspects of food intake. The instrument

  9. An instrument to assess quality of life in relation to nutrition: item generation, item reduction and initial validation.

    Science.gov (United States)

    Schünemann, Holger J; Sperati, Francesca; Barba, Maddalena; Santesso, Nancy; Melegari, Camilla; Akl, Elie A; Guyatt, Gordon; Muti, Paola

    2010-03-11

    It is arguable that modification of diet, given its potential for positive health outcomes, should be widely advocated and adopted. However, food intake, as a basic human need, and its modification may be accompanied by sensations of both pleasure and despondency and may consequently affect to quality of life (QoL). Thus, the feasibility and success of dietary changes will depend, at least partly, on whether potential negative influences on QoL can be avoided. This is of particular importance in the context of dietary intervention studies and in the development of new food products to improve health and well being. Instruments to measure the impact of nutrition on quality of life in the general population, however, are few and far between. Therefore, the aim of this project was to develop an instrument for measuring QoL related to nutrition in the general population. We recruited participants from the general population and followed standard methodology for quality of life instrument development (identification of population, item selection, n = 24; item reduction, n = 81; item presentation, n = 12; pretesting of questionnaire and initial validation, n = 2576; construct validation n = 128; and test-retest reliability n = 20). Of 187 initial items, 29 were selected for final presentation. Factor analysis revealed an instrument with 5 domains. The instrument demonstrated good cross-sectional divergent and convergent construct validity when correlated with scores of the 8 domains of the SF-36 (ranging from -0.078 to 0.562, 19 out of 40 tested correlations were statistically significant and 24 correlations were predicted correctly) and good test-retest reliability (intra-class correlation coefficients from 0.71 for symptoms to 0.90). We developed and validated an instrument with 29 items across 5 domains to assess quality of life related to nutrition and other aspects of food intake. The instrument demonstrated good face and construct validity as well as good

  10. Measuring single constructs by single items: Constructing an even shorter version of the “Short Five” personality inventory

    Science.gov (United States)

    Konstabel, Kenn; Lönnqvist, Jan-Erik; Leikas, Sointu; García Velázquez, Regina; Qin, Hiaying; Verkasalo, Markku; Walkowitz, Gari

    2017-01-01

    The aim of this study was to construct a short, 30-item personality questionnaire that would be, in terms of content and meaning of the scores, as comparable as possible with longer, well-established inventories such as NEO PI-R and its clones. To do this, we shortened the formerly constructed 60-item “Short Five” (S5) by half so that each subscale would be represented by a single item. We compared all possibilities of selecting 30 items (preserving balanced keying within each domain of the five-factor model) in terms of correlations with well-established scales, self-peer correlations, and clarity of meaning, and selected an optimal combination for each domain. The resulting shortened questionnaire, XS5, was compared to the original S5 using data from student samples in 6 different countries (Estonia, Finland, UK, Germany, Spain, and China), and a representative Finnish sample. The correlations between XS5 domain scales and their longer counterparts from well-established scales ranged from 0.74 to 0.84; the difference from the equivalent correlations for full version of S5 or from meta-analytic short-term dependability coefficients of NEO PI-R was not large. In terms of prediction of external criteria (emotional experience and self-reported behaviours), there were no important differences between XS5, S5, and the longer well-established scales. Controlling for acquiescence did not improve the prediction of criteria, self-peer correlations, or correlations with longer scales, but it did improve internal reliability and, in some analyses, comparability of the principal component structure. XS5 can be recommended as an economic measure of the five-factor model of personality at the level of domain scales; it has reasonable psychometric properties, fair correlations with longer well-established scales, and it can predict emotional experience and self-reported behaviours no worse than S5. When subscales are essential, we would still recommend using the full version

  11. Measuring single constructs by single items: Constructing an even shorter version of the "Short Five" personality inventory.

    Directory of Open Access Journals (Sweden)

    Kenn Konstabel

    Full Text Available The aim of this study was to construct a short, 30-item personality questionnaire that would be, in terms of content and meaning of the scores, as comparable as possible with longer, well-established inventories such as NEO PI-R and its clones. To do this, we shortened the formerly constructed 60-item "Short Five" (S5 by half so that each subscale would be represented by a single item. We compared all possibilities of selecting 30 items (preserving balanced keying within each domain of the five-factor model in terms of correlations with well-established scales, self-peer correlations, and clarity of meaning, and selected an optimal combination for each domain. The resulting shortened questionnaire, XS5, was compared to the original S5 using data from student samples in 6 different countries (Estonia, Finland, UK, Germany, Spain, and China, and a representative Finnish sample. The correlations between XS5 domain scales and their longer counterparts from well-established scales ranged from 0.74 to 0.84; the difference from the equivalent correlations for full version of S5 or from meta-analytic short-term dependability coefficients of NEO PI-R was not large. In terms of prediction of external criteria (emotional experience and self-reported behaviours, there were no important differences between XS5, S5, and the longer well-established scales. Controlling for acquiescence did not improve the prediction of criteria, self-peer correlations, or correlations with longer scales, but it did improve internal reliability and, in some analyses, comparability of the principal component structure. XS5 can be recommended as an economic measure of the five-factor model of personality at the level of domain scales; it has reasonable psychometric properties, fair correlations with longer well-established scales, and it can predict emotional experience and self-reported behaviours no worse than S5. When subscales are essential, we would still recommend using the

  12. Measuring single constructs by single items: Constructing an even shorter version of the "Short Five" personality inventory.

    Science.gov (United States)

    Konstabel, Kenn; Lönnqvist, Jan-Erik; Leikas, Sointu; García Velázquez, Regina; Qin, Hiaying; Verkasalo, Markku; Walkowitz, Gari

    2017-01-01

    The aim of this study was to construct a short, 30-item personality questionnaire that would be, in terms of content and meaning of the scores, as comparable as possible with longer, well-established inventories such as NEO PI-R and its clones. To do this, we shortened the formerly constructed 60-item "Short Five" (S5) by half so that each subscale would be represented by a single item. We compared all possibilities of selecting 30 items (preserving balanced keying within each domain of the five-factor model) in terms of correlations with well-established scales, self-peer correlations, and clarity of meaning, and selected an optimal combination for each domain. The resulting shortened questionnaire, XS5, was compared to the original S5 using data from student samples in 6 different countries (Estonia, Finland, UK, Germany, Spain, and China), and a representative Finnish sample. The correlations between XS5 domain scales and their longer counterparts from well-established scales ranged from 0.74 to 0.84; the difference from the equivalent correlations for full version of S5 or from meta-analytic short-term dependability coefficients of NEO PI-R was not large. In terms of prediction of external criteria (emotional experience and self-reported behaviours), there were no important differences between XS5, S5, and the longer well-established scales. Controlling for acquiescence did not improve the prediction of criteria, self-peer correlations, or correlations with longer scales, but it did improve internal reliability and, in some analyses, comparability of the principal component structure. XS5 can be recommended as an economic measure of the five-factor model of personality at the level of domain scales; it has reasonable psychometric properties, fair correlations with longer well-established scales, and it can predict emotional experience and self-reported behaviours no worse than S5. When subscales are essential, we would still recommend using the full version of

  13. International Assessment: A Rasch Model and Teachers' Evaluation of TIMSS Science Achievement Items

    Science.gov (United States)

    Glynn, Shawn M.

    2012-01-01

    The Trends in International Mathematics and Science Study (TIMSS) is a comparative assessment of the achievement of students in many countries. In the present study, a rigorous independent evaluation was conducted of a representative sample of TIMSS science test items because item quality influences the validity of the scores used to inform…

  14. Applying Unidimensional and Multidimensional Item Response Theory Models in Testlet-Based Reading Assessment

    Science.gov (United States)

    Min, Shangchao; He, Lianzhen

    2014-01-01

    This study examined the relative effectiveness of the multidimensional bi-factor model and multidimensional testlet response theory (TRT) model in accommodating local dependence in testlet-based reading assessment with both dichotomously and polytomously scored items. The data used were 14,089 test-takers' item-level responses to the testlet-based…

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

    Science.gov (United States)

    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…

  16. Fuzzy Decision-Making Approach in Geometric Programming for a Single Item EOQ Model

    Directory of Open Access Journals (Sweden)

    Monalisha Pattnaik

    2015-06-01

    Full Text Available Background and methods: Fuzzy decision-making approach is allowed in geometric programming for a single item EOQ model with dynamic ordering cost and demand-dependent unit cost. The setup cost varies with the quantity produced/purchased and the modification of objective function with storage area in the presence of imprecisely estimated parameters are investigated.  It incorporates all concepts of a fuzzy arithmetic approach, the quantity ordered, and demand per unit compares both fuzzy geometric programming technique and other models for linear membership functions.  Results and conclusions: Investigation of the properties of an optimal solution allows developing an algorithm whose validity is illustrated through an example problem and the results discu ssed. Sensitivity analysis of the optimal solution is also studied with respect to changes in different parameter values.  

  17. Assessment of Differential Item Functioning in the Experiences of Discrimination Index

    Science.gov (United States)

    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

  18. Normative data for the 12 item WHO Disability Assessment Schedule 2.0.

    Directory of Open Access Journals (Sweden)

    Gavin Andrews

    Full Text Available BACKGROUND: The World Health Organization Disability Assessment Schedule (WHODAS 2.0 measures disability due to health conditions including diseases, illnesses, injuries, mental or emotional problems, and problems with alcohol or drugs. METHOD: The 12 Item WHODAS 2.0 was used in the second Australian Survey of Mental Health and Well-being. We report the overall factor structure and the distribution of scores and normative data (means and SDs for people with any physical disorder, any mental disorder and for people with neither. FINDINGS: A single second order factor justifies the use of the scale as a measure of global disability. People with mental disorders had high scores (mean 6.3, SD 7.1, people with physical disorders had lower scores (mean 4.3, SD 6.1. People with no disorder covered by the survey had low scores (mean 1.4, SD 3.6. INTERPRETATION: The provision of normative data from a population sample of adults will facilitate use of the WHODAS 2.0 12 item scale in clinical and epidemiological research.

  19. Normative data for the 12 item WHO Disability Assessment Schedule 2.0.

    Science.gov (United States)

    Andrews, Gavin; Kemp, Alice; Sunderland, Matthew; Von Korff, Michael; Ustun, Tevik Bedirhan

    2009-12-17

    The World Health Organization Disability Assessment Schedule (WHODAS 2.0) measures disability due to health conditions including diseases, illnesses, injuries, mental or emotional problems, and problems with alcohol or drugs. The 12 Item WHODAS 2.0 was used in the second Australian Survey of Mental Health and Well-being. We report the overall factor structure and the distribution of scores and normative data (means and SDs) for people with any physical disorder, any mental disorder and for people with neither. A single second order factor justifies the use of the scale as a measure of global disability. People with mental disorders had high scores (mean 6.3, SD 7.1), people with physical disorders had lower scores (mean 4.3, SD 6.1). People with no disorder covered by the survey had low scores (mean 1.4, SD 3.6). The provision of normative data from a population sample of adults will facilitate use of the WHODAS 2.0 12 item scale in clinical and epidemiological research.

  20. Ability or Access-Ability: Differential Item Functioning of Items on Alternate Performance-Based Assessment Tests for Students with Visual Impairments

    Science.gov (United States)

    Zebehazy, Kim T.; Zigmond, Naomi; Zimmerman, George J.

    2012-01-01

    Introduction: This study investigated differential item functioning (DIF) of test items on Pennsylvania's Alternate System of Assessment (PASA) for students with visual impairments and severe cognitive disabilities and what the reasons for the differences may be. Methods: The Wilcoxon signed ranks test was used to analyze differences in the scores…

  1. A single-item global job satisfaction measure is associated with quantitative blood immune indices in white-collar employees.

    Science.gov (United States)

    Nakata, Akinori; Irie, Masahiro; Takahashi, Masaya

    2013-01-01

    Although a single-item job satisfaction measure has been shown to be reliable and inclusive as multiple-item scales in relation to health, studies including immunological data are few. The purpose of this study was to evaluate the validity of single-item job and family life satisfaction based on its association with immune indices. A total of 189 white-collar employees (70% men) underwent a blood draw for the measurement of natural killer (NK), total T, and B cell counts as well as plasma immunoglobulin (Ig) G concentrations and completed single-item job and family life satisfaction measures, respectively. The response options for satisfaction measures were 'dissatisfied' (coded 1) to 'satisfied' (coded 4). Spearman's partial correlations controlling for cofactors revealed that increased job satisfaction was positively associated with NK cells (rsp=0.201, p=0.007) and IgG (rsp=0.178, p=0.018), while family life satisfaction was unrelated to immune indices. Those who reported a combination of low job/low family life satisfaction had significantly lower NK and higher B cell counts than those with a high job/high family life satisfaction. Our study suggests that the single-item summary measure of job satisfaction, but not family life satisfaction, may be a valid tool to evaluate immune status in healthy white-collar employees.

  2. Identifying items to assess methodological quality in physical therapy trials: a factor analysis.

    Science.gov (United States)

    Armijo-Olivo, Susan; Cummings, Greta G; Fuentes, Jorge; Saltaji, Humam; Ha, Christine; Chisholm, Annabritt; Pasichnyk, Dion; Rogers, Todd

    2014-09-01

    Numerous tools and individual items have been proposed to assess the methodological quality of randomized controlled trials (RCTs). The frequency of use of these items varies according to health area, which suggests a lack of agreement regarding their relevance to trial quality or risk of bias. The objectives of this study were: (1) to identify the underlying component structure of items and (2) to determine relevant items to evaluate the quality and risk of bias of trials in physical therapy by using an exploratory factor analysis (EFA). A methodological research design was used, and an EFA was performed. Randomized controlled trials used for this study were randomly selected from searches of the Cochrane Database of Systematic Reviews. Two reviewers used 45 items gathered from 7 different quality tools to assess the methodological quality of the RCTs. An exploratory factor analysis was conducted using the principal axis factoring (PAF) method followed by varimax rotation. Principal axis factoring identified 34 items loaded on 9 common factors: (1) selection bias; (2) performance and detection bias; (3) eligibility, intervention details, and description of outcome measures; (4) psychometric properties of the main outcome; (5) contamination and adherence to treatment; (6) attrition bias; (7) data analysis; (8) sample size; and (9) control and placebo adequacy. Because of the exploratory nature of the results, a confirmatory factor analysis is needed to validate this model. To the authors' knowledge, this is the first factor analysis to explore the underlying component items used to evaluate the methodological quality or risk of bias of RCTs in physical therapy. The items and factors represent a starting point for evaluating the methodological quality and risk of bias in physical therapy trials. Empirical evidence of the association among these items with treatment effects and a confirmatory factor analysis of these results are needed to validate these items.

  3. Validity and usefulness of a single-item measure of patient-reported bother from side effects of cancer therapy.

    Science.gov (United States)

    Pearman, Timothy P; Beaumont, Jennifer L; Mroczek, Daniel; O'Connor, Mary; Cella, David

    2018-03-01

    The improving efficacy of cancer treatment has resulted in an increasing array of treatment-related symptoms and associated burdens imposed on individuals undergoing aggressive treatment of their disease. Often, clinical trials compare therapies that have different types, and severities, of adverse effects. Whether rated by clinicians or patients themselves, it can be difficult to know which side effect profile is more disruptive or bothersome to patients. A simple summary index of bother can help to adjudicate the variability in adverse effects across treatments being compared with each other. Across 4 studies, a total of 5765 patients enrolled in cooperative group studies and industry-sponsored clinical trials were the subjects of the current study. Patients were diagnosed with a range of primary cancer sites, including bladder, brain, breast, colon/rectum, head/neck, hepatobiliary, kidney, lung, ovary, pancreas, and prostate as well as leukemia and lymphoma. All patients were administered the Functional Assessment of Cancer Therapy-General version (FACT-G). The single item "I am bothered by side effects of treatment" (GP5), rated on a 5-point Likert scale, is part of the FACT-G. To determine its validity as a useful summary measure from the patient perspective, it was correlated with individual and aggregated clinician-rated adverse events and patient reports of their general ability to enjoy life. Analyses of pharmaceutical trials demonstrated that mean GP5 scores ("I am bothered by side effects of treatment") significantly differed by maximum adverse event grade (PEffect sizes ranged from 0.13 to 0.46. Analyses of cooperative group trials demonstrated a significant correlation between GP5 and item GF3 ("I am able to enjoy life") in the predicted direction. The single FACT-G item "I am bothered by side effects of treatment" is significantly associated with clinician-reported adverse events and with patients' ability to enjoy their lives. It has promise as an

  4. Working Memory for Sequences of Temporal Durations Reveals a Volatile Single-Item Store.

    Science.gov (United States)

    Manohar, Sanjay G; Husain, Masud

    2016-01-01

    When a sequence is held in working memory, different items are retained with differing fidelity. Here we ask whether a sequence of brief time intervals that must be remembered show recency effects, similar to those observed in verbal and visuospatial working memory. It has been suggested that prioritizing some items over others can be accounted for by a "focus of attention," maintaining some items in a privileged state. We therefore also investigated whether such benefits are vulnerable to disruption by attention or expectation. Participants listened to sequences of one to five tones, of varying durations (200 ms to 2 s). Subsequently, the length of one of the tones in the sequence had to be reproduced by holding a key. The discrepancy between the reproduced and actual durations quantified the fidelity of memory for auditory durations. Recall precision decreased with the number of items that had to be remembered, and was better for the first and last items of sequences, in line with set-size and serial position effects seen in other modalities. To test whether attentional filtering demands might impair performance, an irrelevant variation in pitch was introduced in some blocks of trials. In those blocks, memory precision was worse for sequences that consisted of only one item, i.e., the smallest memory set-size. Thus, when irrelevant information was present, the benefit of having only one item in memory is attenuated. Finally we examined whether expectation could interfere with memory. On half the trials, the number of items in the upcoming sequence was cued. When the number of items was known in advance, performance was paradoxically worse when the sequence consisted of only one item. Thus the benefit of having only one item to remember is stronger when it is unexpectedly the only item. Our results suggest that similar mechanisms are used to hold auditory time durations in working memory, as for visual or verbal stimuli. Further, solitary items were remembered

  5. Working memory for sequences of temporal durations reveals a volatile single-item store

    Directory of Open Access Journals (Sweden)

    Sanjay G Manohar

    2016-10-01

    Full Text Available When a sequence is held in working memory, different items are retained with differing fidelity. Here we ask whether a sequence of brief time intervals that must be remembered show recency effects, similar to those observed in verbal and visuospatial working memory. It has been suggested that prioritising some items over others can be accounted for by a focus of attention, maintaining some items in a privileged state. We therefore also investigated whether such benefits are vulnerable to disruption by attention or expectation. Participants listened to sequences of one to five tones, of varying durations (200ms to 2s. Subsequently, the length of one of the tones in the sequence had to be reproduced by holding a key. The discrepancy between the reproduced and actual durations quantified the fidelity of memory for auditory durations. Recall precision decreased with the number of items that had to be remembered, and was better for the first and last items of sequences, in line with set-size and serial position effects seen in other modalities. To test whether attentional filtering demands might impair performance, an irrelevant variation in pitch was introduced in some blocks of trials. In those blocks, memory precision was worse for sequences that consisted of only one item, i.e. the smallest memory set size. Thus, when irrelevant information was present, the benefit of having only one item in memory is attenuated. Finally we examined whether expectation could interfere with memory. On half the trials, the number of items in the upcoming sequence was cued. When the number of items was known in advance, performance was paradoxically worse when the sequence consisted of only one item. Thus the benefit of having only one item to remember is stronger when it is unexpectedly the only item. Our results suggest that similar mechanisms are used to hold auditory time durations in working memory, as for visual or verbal stimuli. Further, solitary items were

  6. 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.

  7. Using Item Analysis to Assess Objectively the Quality of the Calgary-Cambridge OSCE Checklist

    Directory of Open Access Journals (Sweden)

    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.

  8. Modeling the World Health Organization Disability Assessment Schedule II using non-parametric item response models.

    Science.gov (United States)

    Galindo-Garre, Francisca; Hidalgo, María Dolores; Guilera, Georgina; Pino, Oscar; Rojo, J Emilio; Gómez-Benito, Juana

    2015-03-01

    The World Health Organization Disability Assessment Schedule II (WHO-DAS II) is a multidimensional instrument developed for measuring disability. It comprises six domains (getting around, self-care, getting along with others, life activities and participation in society). The main purpose of this paper is the evaluation of the psychometric properties for each domain of the WHO-DAS II with parametric and non-parametric Item Response Theory (IRT) models. A secondary objective is to assess whether the WHO-DAS II items within each domain form a hierarchy of invariantly ordered severity indicators of disability. A sample of 352 patients with a schizophrenia spectrum disorder is used in this study. The 36 items WHO-DAS II was administered during the consultation. Partial Credit and Mokken scale models are used to study the psychometric properties of the questionnaire. The psychometric properties of the WHO-DAS II scale are satisfactory for all the domains. However, we identify a few items that do not discriminate satisfactorily between different levels of disability and cannot be invariantly ordered in the scale. In conclusion the WHO-DAS II can be used to assess overall disability in patients with schizophrenia, but some domains are too general to assess functionality in these patients because they contain items that are not applicable to this pathology. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Evaluation of the single-item self-rating adherence scale for use in routine clinical care of people living with HIV.

    Science.gov (United States)

    Feldman, B J; Fredericksen, R J; Crane, P K; Safren, S A; Mugavero, M J; Willig, James H; Simoni, J M; Wilson, I B; Saag, M S; Kitahata, M M; Crane, H M

    2013-01-01

    The self-rating scale item (SRSI) is a single-item self-report adherence measure that uses adjectives in a 5-point Likert scale, from "very poor" to "excellent," to describe medication adherence over the past 4 weeks. This study investigated the SRSI in 2,399 HIV-infected patients in routine care at two outpatient primary HIV clinics. Correlations between the SRSI and four commonly used adherence items ranged from 0.37 to 0.64. Correlations of adherence barriers, such as depression and substance use, were comparable across all adherence items. General estimating equations suggested the SRSI is as good as or better than other adherence items (p's <0.001 vs. <0.001-0.99) at predicting adherence-related clinical outcomes, such as HIV viral load and CD4(+) cell count. These results and the SRSI's low patient burden suggest its routine use could be helpful for assessing adherence in clinical care and should be more widespread, particularly where more complex instruments may be impractical.

  10. Small group learning: effect on item analysis and accuracy of self-assessment of medical students.

    Science.gov (United States)

    Biswas, Shubho Subrata; Jain, Vaishali; Agrawal, Vandana; Bindra, Maninder

    2015-01-01

    Small group sessions are regarded as a more active and student-centered approach to learning. Item analysis provides objective evidence of whether such sessions improve comprehension and make the topic easier for students, in addition to assessing the relative benefit of the sessions to good versus poor performers. Self-assessment makes students aware of their deficiencies. Small group sessions can also help students develop the ability to self-assess. This study was carried out to assess the effect of small group sessions on item analysis and students' self-assessment. A total of 21 female and 29 male first year medical students participated in a small group session on topics covered by didactic lectures two weeks earlier. It was preceded and followed by two multiple choice question (MCQ) tests, in which students were asked to self-assess their likely score. The MCQs used were item analyzed in a previous group and were chosen of matching difficulty and discriminatory indices for the pre- and post-tests. The small group session improved the marks of both genders equally, but female performance was better. The session made the items easier; increasing the difficulty index significantly but there was no significant alteration in the discriminatory index. There was overestimation in the self-assessment of both genders, but male overestimation was greater. The session improved the self-assessment of students in terms of expected marks and expectation of passing. Small group session improved the ability of students to self-assess their knowledge and increased the difficulty index of items reflecting students' better performance.

  11. Robustness of two single-item self-esteem measures: cross-validation with a measure of stigma in a sample of psychiatric patients.

    Science.gov (United States)

    Bagley, Christopher

    2005-08-01

    Robins' Single-item Self-esteem Inventory was compared with a single item from the Coopersmith Self-esteem. Although a new scoring format was used, there was good evidence of cross-validation in 83 current and former psychiatric patients who completed Harvey's adapted measure of stigma felt and experienced by users of mental health services. Scores on the two single-item self-esteem measures correlated .76 (p self-esteem in users of mental health services.

  12. Confirmatory factor analysis of 12-Item World Health Organization Disability Assessment Schedule in patients with musculoskeletal pain conditions.

    Science.gov (United States)

    Saltychev, Mikhail; Mattie, Ryan; McCormick, Zachary; Laimi, Katri

    2017-05-01

    To investigate the factor structure of the 12 item World Health Organization Disability Assessment Schedule (WHODAS) 2.0. Cross-sectional cohort survey study. Physical and Rehabilitation Medicine outpatient university clinic. The 408 consecutive patients with chronic musculoskeletal pain. Exploratory and confirmatory factor analysis. A two-factor model most accurately fit the observed data of musculoskeletal pain patients (root mean square error of approximation 0.049, relative Chi square value 1.99). Twelve WHODAS 2.0 items were distributed between two factors with covariance between them of 0.8. The first factor contained domains related mostly to physical functioning, while another was associated mostly with social and cognitive functioning. There were a few differences between single items in their importance in defining the variance within these two factors. Of the six International Classification of Functioning, Disability and Health domains belonging to the first construct, the ability to carry out household responsibilities explained most, 84% of the total variance in this construct. For the second factor, the ability to participate in community activities seemed to be the most important, explaining 85% of the total variance in this construct. In this study, the two-factor structure model of the 12-item WODAS 2.0 demonstrated the most accurate fit within patients with musculoskeletal pain conditions.

  13. The Matching Criterion Purification for Differential Item Functioning Analyses in a Large-Scale Assessment

    Science.gov (United States)

    Lee, HyeSun; Geisinger, Kurt F.

    2016-01-01

    The current study investigated the impact of matching criterion purification on the accuracy of differential item functioning (DIF) detection in large-scale assessments. The three matching approaches for DIF analyses (block-level matching, pooled booklet matching, and equated pooled booklet matching) were employed with the Mantel-Haenszel…

  14. The Value of Item Response Theory in Clinical Assessment: A Review

    Science.gov (United States)

    Thomas, Michael L.

    2011-01-01

    Item response theory (IRT) and related latent variable models represent modern psychometric theory, the successor to classical test theory in psychological assessment. Although IRT has become prevalent in the measurement of ability and achievement, its contributions to clinical domains have been less extensive. Applications of IRT to clinical…

  15. Improving the Memory Sections of the Standardized Assessment of Concussion Using Item Analysis

    Science.gov (United States)

    McElhiney, Danielle; Kang, Minsoo; Starkey, Chad; Ragan, Brian

    2014-01-01

    The purpose of the study was to improve the immediate and delayed memory sections of the Standardized Assessment of Concussion (SAC) by identifying a list of more psychometrically sound items (words). A total of 200 participants with no history of concussion in the previous six months (aged 19.60 ± 2.20 years; N?=?93 men, N?=?107 women)…

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

    Science.gov (United States)

    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…

  17. Item analysis of single-peaked response data : the psychometric evaluation of bipolar measurement scales

    NARCIS (Netherlands)

    Polak, Maaike Geertruida

    2011-01-01

    The thesis explains the fundamental difference between unipolar and bipolar measurement scales for psychological characteristics. We explore the use of correspondence analysis (CA), a technique that is similar to principal component analysis and is available in SAS and SPSS, to select items that

  18. RT-based memory detection : Item saliency effects in the single-probe and the multiple-probe protocol

    NARCIS (Netherlands)

    Verschuere, B.; Kleinberg, B.; Theocharidou, K.

    RT-based memory detection may provide an efficient means to assess recognition of concealed information. There is, however, considerable heterogeneity in detection rates, and we explored two potential moderators: item saliency and test protocol. Participants tried to conceal low salient (e.g.,

  19. An introduction to Item Response Theory and Rasch Analysis of the Eating Assessment Tool (EAT-10).

    Science.gov (United States)

    Kean, Jacob; Brodke, Darrel S; Biber, Joshua; Gross, Paul

    2018-03-01

    Item response theory has its origins in educational measurement and is now commonly applied in health-related measurement of latent traits, such as function and symptoms. This application is due in large part to gains in the precision of measurement attributable to item response theory and corresponding decreases in response burden, study costs, and study duration. The purpose of this paper is twofold: introduce basic concepts of item response theory and demonstrate this analytic approach in a worked example, a Rasch model (1PL) analysis of the Eating Assessment Tool (EAT-10), a commonly used measure for oropharyngeal dysphagia. The results of the analysis were largely concordant with previous studies of the EAT-10 and illustrate for brain impairment clinicians and researchers how IRT analysis can yield greater precision of measurement.

  20. Utility and validity of a single-item visual analog scale for measuring dental anxiety in clinical practice.

    Science.gov (United States)

    Appukuttan, Devapriya; Vinayagavel, Mythreyi; Tadepalli, Anupama

    2014-06-01

    We evaluated whether a visual analog scale (VAS) was comparable to the multi-item Modified Dental Anxiety Scale (MDAS) in assessing dental anxiety in clinical practice. In total, 200 consecutive patients aged 20-70 years who presented at the dental outpatient department of SRM Dental College, Chennai were enrolled. The test-retest value for the VAS was 0.968. The Spearman rank correlations between the VAS and MDAS items and total score were significant (P dental visit and the VAS also showed a strong correlation (r = 0.473, P dental phobia. The weighted kappa was 69% for agreement between MDAS and the VAS in identifying patients with and without dental anxiety at cut-offs of 13 and 4.75, respectively. The VAS was found to be a valid measure and was comparable to the multi-item MDAS.

  1. Examining the Psychometric Quality of Multiple-Choice Assessment Items using Mokken Scale Analysis.

    Science.gov (United States)

    Wind, Stefanie A

    The concept of invariant measurement is typically associated with Rasch measurement theory (Engelhard, 2013). Concerned with the appropriateness of the parametric transformation upon which the Rasch model is based, Mokken (1971) proposed a nonparametric procedure for evaluating the quality of social science measurement that is theoretically and empirically related to the Rasch model. Mokken's nonparametric procedure can be used to evaluate the quality of dichotomous and polytomous items in terms of the requirements for invariant measurement. Despite these potential benefits, the use of Mokken scaling to examine the properties of multiple-choice (MC) items in education has not yet been fully explored. A nonparametric approach to evaluating MC items is promising in that this approach facilitates the evaluation of assessments in terms of invariant measurement without imposing potentially inappropriate transformations. Using Rasch-based indices of measurement quality as a frame of reference, data from an eighth-grade physical science assessment are used to illustrate and explore Mokken-based techniques for evaluating the quality of MC items. Implications for research and practice are discussed.

  2. Development of an assessment tool to measure students′ perceptions of respiratory care education programs: Item generation, item reduction, and preliminary validation

    Directory of Open Access Journals (Sweden)

    Ghazi Alotaibi

    2013-01-01

    Full Text Available Objectives: Students who perceived their learning environment positively are more likely to develop effective learning strategies, and adopt a deep learning approach. Currently, there is no validated instrument for measuring the educational environment of educational programs on respiratory care (RC. The aim of this study was to develop an instrument to measure students′ perception of the RC educational environment. Materials and Methods: Based on the literature review and an assessment of content validity by multiple focus groups of RC educationalists, potential items of the instrument relevant to RC educational environment construct were generated by the research group. The initial 71 item questionnaire was then field-tested on all students from the 3 RC programs in Saudi Arabia and was subjected to multi-trait scaling analysis. Cronbach′s alpha was used to assess internal consistency reliabilities. Results: Two hundred and twelve students (100% completed the survey. The initial instrument of 71 items was reduced to 65 across 5 scales. Convergent and discriminant validity assessment demonstrated that the majority of items correlated more highly with their intended scale than a competing one. Cronbach′s alpha exceeded the standard criterion of >0.70 in all scales except one. There was no floor or ceiling effect for scale or overall score. Conclusions: This instrument is the first assessment tool developed to measure the RC educational environment. There was evidence of its good feasibility, validity, and reliability. This first validation of the instrument supports its use by RC students to evaluate educational environment.

  3. Open Single Item of Perceived Risk Factors (OSIPRF toward Cardiovascular Diseases Is an Appropriate Instrument for Evaluating Psychological Symptoms

    Directory of Open Access Journals (Sweden)

    Mozhgan Saeidi

    2016-12-01

    Full Text Available Psychological symptoms are considered as one of the aspects and consequences of cardiovascular diseases (CVDs, management of which can precipitate and facilitate the process of recovery. Evaluation of the psychological symptoms can increase awareness of treatment team regarding patients’ mental health, which can be beneficial for designing treatment programs (1. However, time-consuming process of interviews and assessment by questionnaires lead to fatigue and lack of patient cooperation, which may be problematic for healthcare evaluators. Therefore, the use of brief and suitable alternatives is always recommended.The use of practical and easy to implement instruments is constantly emphasized. A practical method for assessing patients' psychological status is examining causal beliefs and attitudes about the disease. The causal beliefs and perceived risk factors by patients, which are significantly related to the actual risk factors for CVDs (2, are not only related to psychological adjustment and mental health but also have an impact on patients’ compliance with treatment recommendations (3.It seems that several risk factors are at play regarding the perceived risk factors for CVDs such as gender (4, age (5, and most importantly, patients’ psychological status (3. Accordingly, evaluation of causal beliefs and perceived risk factors by patients could probably be a shortcut method for evaluation of patients’ psychological health. In recent years, Saeidi and Komasi (5 proposed a question and investigated the perceived risk factors with an open single item: “What do you think is the main cause of your illness?”. According to the authors, the perceived risk factors are recorded in five categories including biological (age, gender, and family history, environmental (dust, smoke, passive smoking, toxic substances, and effects of war, physiological (diabetes, hypertension, hyperlipidemia, and obesity, behavioral (lack of exercise, nutrition

  4. 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

  5. Improved utilization of ADAS-cog assessment data through item response theory based pharmacometric modeling.

    Science.gov (United States)

    Ueckert, Sebastian; Plan, Elodie L; Ito, Kaori; Karlsson, Mats O; Corrigan, Brian; Hooker, Andrew C

    2014-08-01

    This work investigates improved utilization of ADAS-cog data (the primary outcome in Alzheimer's disease (AD) trials of mild and moderate AD) by combining pharmacometric modeling and item response theory (IRT). A baseline IRT model characterizing the ADAS-cog was built based on data from 2,744 individuals. Pharmacometric methods were used to extend the baseline IRT model to describe longitudinal ADAS-cog scores from an 18-month clinical study with 322 patients. Sensitivity of the ADAS-cog items in different patient populations as well as the power to detect a drug effect in relation to total score based methods were assessed with the IRT based model. IRT analysis was able to describe both total and item level baseline ADAS-cog data. Longitudinal data were also well described. Differences in the information content of the item level components could be quantitatively characterized and ranked for mild cognitively impairment and mild AD populations. Based on clinical trial simulations with a theoretical drug effect, the IRT method demonstrated a significantly higher power to detect drug effect compared to the traditional method of analysis. A combined framework of IRT and pharmacometric modeling permits a more effective and precise analysis than total score based methods and therefore increases the value of ADAS-cog data.

  6. Assessing Testlet Effect, Impact, Differential Testlet, and Item Functioning Using Cross-Classified Multilevel Measurement Modeling

    Directory of Open Access Journals (Sweden)

    Hamdollah Ravand

    2015-05-01

    Full Text Available The present study used the two-level testlet response model (MMMT-2 to assess impact, differential item functioning (DIF, and differential testlet functioning (DTLF in a reading comprehension test. The data came from 21,641 applicants into English Masters’ programs at Iranian state universities. Testlet effects were estimated, and items and testlets that were functioning differentially for test takers of different genders and majors were identified. Also parameter estimates obtained under MMMT-2 and those obtained under the two-level hierarchical generalized linear model (HGLM-2 were compared. The results indicated that ability estimates obtained under the two models were significantly different at the lower and upper ends of the ability distribution. In addition, it was found that ignoring local item dependence (LID would result in overestimation of the precision of the ability estimates. As for the difficulty of the items, the estimates obtained under the two models were almost the same, but standard errors were significantly different.

  7. Development of Rasch-based item banks for the assessment of work performance in patients with musculoskeletal diseases.

    Science.gov (United States)

    Mueller, Evelyn A; Bengel, Juergen; Wirtz, Markus A

    2013-12-01

    This study aimed to develop a self-description assessment instrument to measure work performance in patients with musculoskeletal diseases. In terms of the International Classification of Functioning, Disability and Health (ICF), work performance is defined as the degree of meeting the work demands (activities) at the actual workplace (environment). To account for the fact that work performance depends on the work demands of the job, we strived to develop item banks that allow a flexible use of item subgroups depending on the specific work demands of the patients' jobs. Item development included the collection of work tasks from literature and content validation through expert surveys and patient interviews. The resulting 122 items were answered by 621 patients with musculoskeletal diseases. Exploratory factor analysis to ascertain dimensionality and Rasch analysis (partial credit model) for each of the resulting dimensions were performed. Exploratory factor analysis resulted in four dimensions, and subsequent Rasch analysis led to the following item banks: 'impaired productivity' (15 items), 'impaired cognitive performance' (18), 'impaired coping with stress' (13) and 'impaired physical performance' (low physical workload 20 items, high physical workload 10 items). The item banks exhibited person separation indices (reliability) between 0.89 and 0.96. The assessment of work performance adds the activities component to the more commonly employed participation component of the ICF-model. The four item banks can be adapted to specific jobs where necessary without losing comparability of person measures, as the item banks are based on Rasch analysis.

  8. 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

  9. Randomization and Data-Analysis Items in Quality Standards for Single-Case Experimental Studies

    Science.gov (United States)

    Heyvaert, Mieke; Wendt, Oliver; Van den Noortgate, Wim; Onghena, Patrick

    2015-01-01

    Reporting standards and critical appraisal tools serve as beacons for researchers, reviewers, and research consumers. Parallel to existing guidelines for researchers to report and evaluate group-comparison studies, single-case experimental (SCE) researchers are in need of guidelines for reporting and evaluating SCE studies. A systematic search was…

  10. 48 CFR 245.7101-3 - DD Form 1348-1, DoD Single Line Item Release/Receipt Document.

    Science.gov (United States)

    2010-10-01

    ... PROPERTY Plant Clearance Forms 245.7101-3 DD Form 1348-1, DoD Single Line Item Release/Receipt Document. Use for shipments of excess industrial plant equipment and contractor inventory redistribution system...

  11. Dependability of Two Scaling Approaches to Direct Behavior Rating Multi-Item Scales Assessing Disruptive Classroom Behavior

    Science.gov (United States)

    Volpe, Robert J.; Briesch, Amy M.

    2016-01-01

    This study examines the dependability of two scaling approaches for using a five-item Direct Behavior Rating multi-item scale to assess student disruptive behavior. A series of generalizability theory studies were used to compare a traditional frequency-based scaling approach with an approach wherein the informant compares a target student's…

  12. The Development of Multiple-Choice Items Consistent with the AP Chemistry Curriculum Framework to More Accurately Assess Deeper Understanding

    Science.gov (United States)

    Domyancich, John M.

    2014-01-01

    Multiple-choice questions are an important part of large-scale summative assessments, such as the advanced placement (AP) chemistry exam. However, past AP chemistry exam items often lacked the ability to test conceptual understanding and higher-order cognitive skills. The redesigned AP chemistry exam shows a distinctive shift in item types toward…

  13. Repeatability of food frequency assessment tools in relation to the number of items and response categories included.

    Science.gov (United States)

    Bountziouka, Vassiliki; Bathrellou, Eirini; Zazpe, Itziar; Ezquer, Leyre; Martínez-González, Miguel-Angel; Panagiotakos, Demosthenes B

    2012-12-01

    Accuracy of measurement is a cornerstone of research in order to make robust conclusions about the research hypothesis. To examine whether the number of items (questions) and the number of consumption responses (the coding used to measure the frequency of consumption) included in nutritional assessment tools influence their repeatability. During 2009, 400 participants (250 from Greece, mean age 37 +/- 13 years, 34% males, and 150 from Spain, mean age 39 +/- 17 years, 41% males) completed a diet index with 11 items and binary (yes/ no) responses, a diet index with 11 items and 6-scale responses, and 36-item and 76-item food frequency questionnaires (FFQs) with 6-scale responses. The participants completed these tools twice, with 15 days between the two administrations of the tools. The Spearman-Brown coefficient (r(sb)), Kendall's tau coefficients, and the Bland-Altman method were applied to answer the research hypothesis. The highest repeatability coefficient was observed for the diet index with 11 items and binary (yes/no) responses (r(sb) = 0.948, p tools (p > .23), whereas these three tools had significantly higher repeatability coefficients than the 76-item FFQ (p = .002). Subgroup analyses by sex, education, smoking, and clinical status confirmed these results. Repeatability was found for all food frequency assessment tools used, irrespective of the number of items or the number of responses included.

  14. Construct validity and responsiveness of the single-item presenteeism question in patients with lower back pain for the measurement of presenteeism.

    Science.gov (United States)

    Kigozi, Jesse; Lewis, Martyn; Jowett, Sue; Barton, Pelham; Coast, Joanna

    2014-03-01

    Validity and responsiveness study using a randomized clinical trial and prospective cohort study of patients with low back pain (LBP). To provide evidence for construct validity and responsiveness to change of a single-item presenteeism question (SIPQ) in patients with LBP. The SIPQ is a simple, easy to administer tool that has been used to measure the impact of back pain on reduced productivity at work (presenteeism) as a standalone measure. Evidence supporting the validity and responsiveness of the SIPQ among patients with back pain is however lacking. The SIPQ was administered to patients consulting for back pain in a randomized controlled trial (N = 851) and a cohort intervention study (N = 922). Construct validity was assessed using convergent, divergent, and known-group validity. The validity investigation included assessing associations between the SIPQ and pain, disability, psychological, health status, and quality of life measures. Responsiveness was assessed using external indicators of change as comparators, evaluating correlation of clinical change scores and effect size statistics. Moderate to strong correlations were found between presenteeism and pain (r: 0.44-0.77), disability (r: 0.53-0.70), and 12-Item Short Form Health Survey physical dimensions (r: -0.66 to -0.55). Presenteeism was strongly associated with disease-specific pain and disability scales. The SIPQ was responsive to changes in productivity-presenteeism change scores indicated strong correlation with change scores, and high responsiveness in distribution- and anchor-based testing. The SIPQ is a potentially valid and responsive tool for assessing the impact of back pain on presenteeism. This SIPQ could, with relative ease, facilitate further research on the estimation of presenteeism within economic evaluation studies of musculoskeletal conditions, thus providing policymakers with estimates of economic impact of musculoskeletal disease. Further evidence is, however, merited to assess

  15. Single by choice? Assessing and understanding voluntary singlehood among mature gay men.

    Science.gov (United States)

    Hostetler, Andrew J

    2009-01-01

    This study investigated what it means for mature gay men to be voluntary single from the perspective of both assessment and subjective experience. A convenience sample of 94 self-identified single gay men from a large midwestern city, ages 35 and over, completed a structured questionnaire that included the 15-item Adaptation to Single Status Measure. Twenty of these men also participated in semi-structured life-history interviews. Descriptive, item, and scale analyses indicated a discrepancy between the perception of oneself as "single by choice" and acceptance of and satisfaction with single status. Qualitative data indicated that voluntary singlehood is neither a salient identity nor an expression of primary control; rather, it is an idiosyncratic "narrative strategy" and a form of secondary control that preserves ego integrity. These findings are discussed with respect to their implications for the creation and maintenance of healthy, happy, single lifestyles and communities.

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

    Science.gov (United States)

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

    2017-01-01

    Purpose 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. Methods 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 R2 less than 10 %). Results 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. Conclusion 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. PMID:27048495

  17. 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.

  18. Communicating Quantitative Literacy: An Examination of Open-Ended Assessment Items in TIMSS, NALS, IALS, and PISA

    Directory of Open Access Journals (Sweden)

    Karl W. Kosko

    2011-07-01

    Full Text Available Quantitative Literacy (QL has been described as the skill set an individual uses when interacting with the world in a quantitative manner. A necessary component of this interaction is communication. To this end, assessments of QL have included open-ended items as a means of including communicative aspects of QL. The present study sought to examine whether such open-ended items typically measured aspects of quantitative communication, as compared to mathematical communication, or mathematical skills. We focused on public-released items and rubrics from four of the most widely referenced assessments: the Third International Mathematics and Science Study (TIMSS-95: the National Adult Literacy Survey (NALS; now the National Assessment of Adult Literacy, NAAL in 1985 and 1992, the International Adult Literacy Skills (IALS beginning in 1994; and the Program for International Student Assessment (PISA beginning in 2000. We found that open-ended item rubrics in these QL assessments showed a strong tendency to assess answer-only responses. Therefore, while some open-ended items may have required certain levels of quantitative reasoning to find a solution, it is the solution rather than the reasoning that was often assessed.

  19. Reducing the item number to obtain the same-length self-assessment scales: a systematic approach using result of graphical loglinear rasch models

    DEFF Research Database (Denmark)

    Nielsen, Tine; Kreiner, Svend

    2011-01-01

    . For self-assessment, self-scoring and self-interpretational purposes it is deemed prudent that subscales measuring comparable constructs are of the same item length. Consequently, in order to obtain a self-assessment version of the R-D-LSI with an equal number of items in each subscale, a systematic...... approach to item reduction based on results of graphical loglinear Rasch modeling (GLLRM) was designed. This approach was then used to reduce the number of items in the subscales of the R-D-LSI which had an item-length of more than seven items, thereby obtaining the Danish Self-Assessment Learning Styles...

  20. Repeatability of food frequency assessment tools in relation to the number of items and response categories included

    OpenAIRE

    Bountziouka, V. (Vassiliki); Bathrellou, E. (Eirini); Zazpe, I. (Itziar); Ezquer, L. (Leyre); Martinez-Gonzalez, M.A. (Miguel Ángel); Panagiotakos, D.B. (Demosthenes B.)

    2012-01-01

    Background: Accuracy of a measurement is a cornerstone in research in order to make robust conclusions about the research hypothesis. Objective: To examine whether the number of items (questions) and the number of responses of consumption included in nutritional assessment tools influence their repeatability. Methods: During 2009, 400 participants (250 from Greece, 37±13 yrs, 34% males and 150 participants from Spain, 39±17 yrs, 41% males) completed a diet index with 11-items a...

  1. Item and Test Analysis to Identify Quality Multiple Choice Questions (MCQs) from an Assessment of Medical Students of Ahmedabad, Gujarat.

    Science.gov (United States)

    Gajjar, Sanju; Sharma, Rashmi; Kumar, Pradeep; Rana, Manish

    2014-01-01

    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). 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. Study was conducted in a medical school of Ahmedabad. 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. 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. 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 (students and some issues with framing of at least some of the MCQs. Increased proportion of NFDs (incorrect alternatives selected by 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%. 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.

  2. Assessment of differential item functioning for demographic comparisons in the MOS SF-36 health survey.

    Science.gov (United States)

    Perkins, Anthony J; Stump, Timothy E; Monahan, Patrick O; McHorney, Colleen A

    2006-04-01

    To investigate whether items of the Medical Outcomes Study (MOS) 36-Item Short-Form Health Status Survey (SF-36) exhibited differential item functioning (DIF) with respect to age, education, race, and gender. The data for this study come from two large national datasets, the MOS and the 1990 National Survey of Functional Health Status (NSFHS). We used logistic regression to identify items exhibiting DIF. We found DIF to be most problematic for age comparisons. Items flagged for age DIF were vigorous activities, bend/kneel/stoop, bathing or dressing, limited in kind of work, health in general, get sick easier than others, expect health to get worse, felt calm and peaceful, and all four vitality items. Items flagged for education DIF include vigorous activities, health in general, health is excellent, felt calm and peaceful, and been a happy person. Vigorous activities, walk more than a mile, health in general, and expect health to get worse were identified as DIF when comparing African-Americans with whites. No items were identified for gender DIF. We found several consistent patterns of DIF using two national datasets with different population characteristics. In the current study, the effect of DIF rarely transferred to the scale level. Further research is needed to corroborate these results and determine qualitatively why DIF may occur for these specific items.

  3. Assessing Impact, DIF, and DFF in Accommodated Item Scores: A Comparison of Multilevel Measurement Model Parameterizations

    Science.gov (United States)

    Beretvas, S. Natasha; Cawthon, Stephanie W.; Lockhart, L. Leland; Kaye, Alyssa D.

    2012-01-01

    This pedagogical article is intended to explain the similarities and differences between the parameterizations of two multilevel measurement model (MMM) frameworks. The conventional two-level MMM that includes item indicators and models item scores (Level 1) clustered within examinees (Level 2) and the two-level cross-classified MMM (in which item…

  4. An Application of Cognitive Diagnostic Assessment on TIMMS-2007 8th Grade Mathematics Items

    Science.gov (United States)

    Toker, Turker; Green, Kathy

    2012-01-01

    The least squares distance method (LSDM) was used in a cognitive diagnostic analysis of TIMSS (Trends in International Mathematics and Science Study) items administered to 4,498 8th-grade students from seven geographical regions of Turkey, extending analysis of attributes from content to process and skill attributes. Logit item positions were…

  5. Item and order memory for novel visual patterns assessed by two-choice recognition.

    Science.gov (United States)

    Avons, S E; Ward, Geoff; Melling, Lindsay

    2004-07-01

    Five experiments examined item and order memory for short lists of novel visual patterns. Memory was tested either by an item recognition test, choosing between a target and a similar foil (Experiments 1, 3a, and 4), or by a relative recency decision between two patterns that occupied adjacent list positions (Experiments 2, 3b, and 5). For both item recognition and relative recency tasks, accuracy was in most cases constant across serial positions, except for a recency advantage that was usually restricted to the most recent item or recency decision. Only a small and marginally significant effect of list length was observed for item recognition. Relative recency was more sensitive to list length and fell to near-chance levels with lists of eight items. We conclude that for these materials, prerecency item recognition depends on stable, context-free descriptions of items. Relative recency judgements are sensitive to list properties, but fail to show evidence of primacy or extended recency that are observed when other techniques are used to study serial order memory. We discuss the results in relation to four current models of serial order memory that embody different assumptions in the way that serial order is represented. Copyright 2004 The Experimental Psychology Society

  6. Assessing the Performance of Classical Test Theory Item Discrimination Estimators in Monte Carlo Simulations

    Science.gov (United States)

    Bazaldua, Diego A. Luna; Lee, Young-Sun; Keller, Bryan; Fellers, Lauren

    2017-01-01

    The performance of various classical test theory (CTT) item discrimination estimators has been compared in the literature using both empirical and simulated data, resulting in mixed results regarding the preference of some discrimination estimators over others. This study analyzes the performance of various item discrimination estimators in CTT:…

  7. [Examination of calibrated item banks for the assessment of work capacity in an outpatient sample of cardiological patients].

    Science.gov (United States)

    Haschke, A; Abberger, B; Schröder, K; Wirtz, M; Bengel, J; Baumeister, H

    2013-12-01

    Work capacity is a major outcome variable in cardiological rehabilitation. However, there is a lacks of capacious and economic assessment instruments for work capacity. By developing item response theory based item banks a first step to close this gap is done. The present study aims to validate the work capacity item banks for cardiovascular rehabilitation inpatients (WCIB-Cardio) in a sample of cardiovascular rehabilitation outpatients. Additionally, we examined differences between in- and outpatients with regard to their work capacity. Data of 283 cardiovascular rehabilitation inpatients and 77 cardiovascular rehabilitation outpatients were collected in 15 rehabilitation centres. The WCIB-Cardio contains the 2 domains of "cognitive work capacity"(20 items) and "physical work capacity"(18 items). Validation of the item bank for cardiological outpatients was conducted with separate Rasch analysis for each domain. For the domain of cognitive work capacity 10 items showed satisfying quality criteria (Rasch reliability=0.71; overall model fit=0.07). For the domain of physical work capacity good values for Rasch-reliability (0.83) and overall -model fit (0.65) could be proven after exclusion of 3 items. Unidimensionality and a broad ability spectrum could be covered for both domains. With regard to content, outpatients evaluate themselves less burdened than inpatients for the domain of cognitive work capacity (‾X outpatient =-2.06 vs. ‾X inpatient =-2.49; pphysical work capacity (‾X outpatient =-3.68 vs. ‾X inpatient =-2.88; pcardiological in- and outpatients. © Georg Thieme Verlag KG Stuttgart · New York.

  8. Concurrent Validity and Sensitivity to Change of Direct Behavior Rating Single-Item Scales (DBR-SIS) Within an Elementary Sample.

    Science.gov (United States)

    Smith, Rhonda L; Eklund, Katie; Kilgus, Stephen P

    2017-06-12

    The purpose of this study was to evaluate the concurrent validity, sensitivity to change, and teacher acceptability of Direct Behavior Rating single-item scales (DBR-SIS), a brief progress monitoring measure designed to assess student behavioral change in response to intervention. Twenty-four elementary teacher-student dyads implemented a daily report card intervention to promote positive student behavior during prespecified classroom activities. During both baseline and intervention, teachers completed DBR-SIS ratings of 2 target behaviors (i.e., Academic Engagement, Disruptive Behavior) whereas research assistants collected systematic direct observation (SDO) data in relation to the same behaviors. Five change metrics (i.e., absolute change, percent of change from baseline, improvement rate difference, Tau-U, and standardized mean difference; Gresham, 2005) were calculated for both DBR-SIS and SDO data, yielding estimates of the change in student behavior in response to intervention. Mean DBR-SIS scores were predominantly moderately to highly correlated with SDO data within both baseline and intervention, demonstrating evidence of the former's concurrent validity. DBR-SIS change metrics were also significantly correlated with SDO change metrics for both Disruptive Behavior and Academic Engagement, yielding evidence of the former's sensitivity to change. In addition, teacher Usage Rating Profile-Assessment (URP-A) ratings indicated they found DBR-SIS to be acceptable and usable. Implications for practice, study limitations, and areas of future research are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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

    Science.gov (United States)

    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.

  10. Disability in bipolar I disorder: the 36-item World Health Organization Disability Assessment Schedule 2.0.

    Science.gov (United States)

    Guilera, Georgina; Gómez-Benito, Juana; Pino, Óscar; Rojo, Emilio; Vieta, Eduard; Cuesta, Manuel J; Purdon, Scot E; Bernardo, Miguel; Crespo-Facorro, Benedicto; Franco, Manuel; Martínez-Arán, Anabel; Safont, Gemma; Tabarés-Seisdedos, Rafael; Rejas, Javier

    2015-03-15

    The WHODAS 2.0 is an ICF-based multidimensional instrument developed for measuring disability. The present study analyzes the utility of the 36-item interviewer-administered version in a sample of patients with bipolar disorder. There is no study to date that analyses how the scale works in a sample that only comprises such patients. A total of 291 patients with bipolar disorder (42.6% males) according to DSM-IV-TR criteria from a cross-sectional study conducted in outpatient psychiatric clinics were enrolled. In addition to the WHODAS 2.0, patients completed a comprehensive assessment battery including measures on psychopathology, functionality and quality of life. Analyses were centered on providing evidence on the validity and utility of the Spanish version of the WHODAS 2.0 in bipolar patients. Participation domain had the highest percentage of missing data (2.7%). Confirmatory factorial analysis was used to test three models formulated in the literature: six primary correlated factors, six primary factors with a single second-order factor, and six primary factors with two second-order factors. The three models were plausible, although the one formed by six correlated factors produced the best fit. Cronbach's alpha values ranged between .73 for the Self-care domain and .92 for Life activities, and the internal consistency of the total score was .96. Relationships between the WHODAS 2.0 and measures of psychopathology, functionality and quality of life were in the expected direction, and the scale was found to be able to differentiate among patients with different intensity of clinical symptoms and work situation. The percentage of euthymic patients was considerable. However, the assessment of euthymic patients is less influenced by mood. Some psychometric properties have not been studied, such as score stability and sensitivity to change. The Spanish version of the 36-item WHODAS 2.0 has suitable psychometric properties in terms of reliability and validity when

  11. The validity of the Satisfaction with Life Scale in adolescents and a comparison with single-item life satisfaction measures: a preliminary study.

    Science.gov (United States)

    Jovanović, Veljko

    2016-12-01

    The validity of the life satisfaction measures commonly used among adults has been rarely examined in adolescent samples. The present research had two main goals: (1) to evaluate the structural validity of the Satisfaction with Life Scale (SWLS) among adolescents and to test measurement invariance across gender; (2) to compare the criterion and convergent validity of the SWLS and single-item life satisfaction measures among adolescents. Three samples of Serbian adolescents were recruited for the present research. Study 1 (N = 481, M age  = 17.01 years) examined the structure of the SWLS via confirmatory factor analysis (CFA) and evaluated measurement invariance of the SWLS across gender by a multi-group CFA. Study 2 (N = 283, M age  = 17.34 years) and Study 3 (N = 220, M age  = 16.73 years) compared the convergent validity of the SWLS and single-item life satisfaction measures. The results of Study 1 supported the original one-factor model of the SWLS among adolescents and provided evidence for strong measurement invariance of the SWLS across gender. The findings of Study 2 and Study 3 showed that the SWLS and single-item measures were equally valid and strongly associated (r = .734 in Study 2 and r = .668 in Study 3). No substantial differences in correlations with school success and well-being indicators were found between the SWLS and single-item measures. Our findings support the use of the SWLS among adolescents and indicate that single-item life satisfaction measures perform as well as the SWLS in adolescent samples.

  12. Assessment of English-French differential item functioning of the Satisfaction with Appearance Scale (SWAP) in systemic sclerosis

    NARCIS (Netherlands)

    Jewett, L.R.; Kwakkenbos, C.M.C.; Hudson, M.; Baron, M.; Thombs, B.D.

    2017-01-01

    The Satisfaction with Appearance Scale (SWAP) has been used to assess body image distress among people with the rare and disfiguring disease systemic sclerosis (SSc); however, it has not been validated across different languages groups. The objective was to examine differential item functioning of

  13. Development of an Item Bank for Assessing Generic Competences in a Higher-Education Institute: A Rasch Modelling Approach

    Science.gov (United States)

    Xie, Qin; Zhong, Xiaoling; Wang, Wen-Chung; Lim, Cher Ping

    2014-01-01

    This paper describes the development and validation of an item bank designed for students to assess their own achievements across an undergraduate-degree programme in seven generic competences (i.e., problem-solving skills, critical-thinking skills, creative-thinking skills, ethical decision-making skills, effective communication skills, social…

  14. Using Distractor-Driven Standards-Based Multiple-Choice Assessments and Rasch Modeling to Investigate Hierarchies of Chemistry Misconceptions and Detect Structural Problems with Individual Items

    Science.gov (United States)

    Herrmann-Abell, Cari F.; DeBoer, George E.

    2011-01-01

    Distractor-driven multiple-choice assessment items and Rasch modeling were used as diagnostic tools to investigate students' understanding of middle school chemistry ideas. Ninety-one items were developed according to a procedure that ensured content alignment to the targeted standards and construct validity. The items were administered to 13360…

  15. The future of outcomes measurement: item banking, tailored short-forms, and computerized adaptive assessment.

    Science.gov (United States)

    Cella, David; Gershon, Richard; Lai, Jin-Shei; Choi, Seung

    2007-01-01

    The use of item banks and computerized adaptive testing (CAT) begins with clear definitions of important outcomes, and references those definitions to specific questions gathered into large and well-studied pools, or "banks" of items. Items can be selected from the bank to form customized short scales, or can be administered in a sequence and length determined by a computer programmed for precision and clinical relevance. Although far from perfect, such item banks can form a common definition and understanding of human symptoms and functional problems such as fatigue, pain, depression, mobility, social function, sensory function, and many other health concepts that we can only measure by asking people directly. The support of the National Institutes of Health (NIH), as witnessed by its cooperative agreement with measurement experts through the NIH Roadmap Initiative known as PROMIS (www.nihpromis.org), is a big step in that direction. Our approach to item banking and CAT is practical; as focused on application as it is on science or theory. From a practical perspective, we frequently must decide whether to re-write and retest an item, add more items to fill gaps (often at the ceiling of the measure), re-test a bank after some modifications, or split up a bank into units that are more unidimensional, yet less clinically relevant or complete. These decisions are not easy, and yet they are rarely unforgiving. We encourage people to build practical tools that are capable of producing multiple short form measures and CAT administrations from common banks, and to further our understanding of these banks with various clinical populations and ages, so that with time the scores that emerge from these many activities begin to have not only a common metric and range, but a shared meaning and understanding across users. In this paper, we provide an overview of item banking and CAT, discuss our approach to item banking and its byproducts, describe testing options, discuss an

  16. 'Do you think you suffer from depression?' Reevaluating the use of a single item question for the screening of depression in older primary care patients

    DEFF Research Database (Denmark)

    Ayalon, Liat; Goldfracht, Margalit; Bech, Per

    2010-01-01

    to existing depression screening tools. METHODS: A cross sectional sample of 153 older primary care patients. Participants completed several depression-screening measures (e.g. a single depression screen, Patient Health Questionnaire-9, Major Depression Inventory, Visual Analogue Scale). Measures were......OBJECTIVES: The majority of older adults seek depression treatment in primary care. Despite impressive efforts to integrate depression treatment into primary care, depression often remains undetected. The overall goal of the present study was to compare a single item screening for depression......: An easy way to detect depression in older primary care patients would be asking the single question, 'do you think you suffer from depression?'...

  17. Re-Examining Test Item Issues in the TIMSS Mathematics and Science Assessments

    Science.gov (United States)

    Wang, Jianjun

    2011-01-01

    As the largest international study ever taken in history, the Trend in Mathematics and Science Study (TIMSS) has been held as a benchmark to measure U.S. student performance in the global context. In-depth analyses of the TIMSS project are conducted in this study to examine key issues of the comparative investigation: (1) item flaws in mathematics…

  18. Differential Item Functioning and educational risk factors in Guatemalan reading assessment

    NARCIS (Netherlands)

    Fortin Morales, A.; van de Vijver, F.J.R.; Poortinga, Y.H.

    2013-01-01

    We examined Differential Item Functioning (DIF) indicators for four variables that repeatedly have been demonstrated to constitute risk factors in primary school achievement in Guatemala. These factors are over-age of enrollment, urban/rural area of residence, ethnicity, and gender. We used scores

  19. Calibration of context-specific survey items to assess youth physical activity behaviour.

    Science.gov (United States)

    Saint-Maurice, Pedro F; Welk, Gregory J; Bartee, R Todd; Heelan, Kate

    2017-05-01

    This study tests calibration models to re-scale context-specific physical activity (PA) items to accelerometer-derived PA. A total of 195 4th-12th grades children wore an Actigraph monitor and completed the Physical Activity Questionnaire (PAQ) one week later. The relative time spent in moderate-to-vigorous PA (MVPA % ) obtained from the Actigraph at recess, PE, lunch, after-school, evening and weekend was matched with a respective item score obtained from the PAQ's. Item scores from 145 participants were calibrated against objective MVPA % using multiple linear regression with age, and sex as additional predictors. Predicted minutes of MVPA for school, out-of-school and total week were tested in the remaining sample (n = 50) using equivalence testing. The results showed that PAQ β-weights ranged from 0.06 (lunch) to 4.94 (PE) MVPA % (P PAQ and accelerometer MVPA at school and out-of-school ranged from -15.6 to +3.8 min and the PAQ was within 10-15% of accelerometer measured activity. This study demonstrated that context-specific items can be calibrated to predict minutes of MVPA in groups of youth during in- and out-of-school periods.

  20. Negative affectivity in cardiovascular disease: Evaluating Type D personality assessment using item response theory

    NARCIS (Netherlands)

    Emons, Wilco H.M.; Meijer, R.R.; Denollet, Johan

    2007-01-01

    Objective: Individuals with increased levels of both negative affectivity (NA) and social inhibition (SI)—referred to as type-D personality—are at increased risk of adverse cardiac events. We used item response theory (IRT) to evaluate NA, SI, and type-D personality as measured by the DS14. The

  1. Assessment of English-French differential item functioning of the Satisfaction with Appearance Scale (SWAP) in systemic sclerosis.

    Science.gov (United States)

    Jewett, Lisa R; Kwakkenbos, Linda; Hudson, Marie; Baron, Murray; Thombs, Brett D

    2017-09-01

    The Satisfaction with Appearance Scale (SWAP) has been used to assess body image distress among people with the rare and disfiguring disease systemic sclerosis (SSc); however, it has not been validated across different languages groups. The objective was to examine differential item functioning of the SWAP among 856 Canadian English- or French-speaking SSc patients. Confirmatory factor analysis was used to evaluate the SWAP two-factor structure (Dissatisfaction with Appearance and Social Discomfort). The Multiple-Indicator Multiple-Cause model was utilized to assess differential item functioning. Results revealed that the established two-factor model of the SWAP demonstrated relatively good fit. Statistically significant, but small-magnitude differential item functioning was found for three SWAP items based on language; however, the cumulative effect on SWAP scores was negligible. Findings provided empirical evidence that SWAP scores from Canadian English- and French-speaking patients can be compared and pooled without concern that measurement differences may substantially influence results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Evaluating measurement equivalence using the item response theory log-likelihood ratio (IRTLR) method to assess differential item functioning (DIF): applications (with illustrations) to measures of physical functioning ability and general distress.

    Science.gov (United States)

    Teresi, Jeanne A; Ocepek-Welikson, Katja; Kleinman, Marjorie; Cook, Karon F; Crane, Paul K; Gibbons, Laura E; Morales, Leo S; Orlando-Edelen, Maria; Cella, David

    2007-01-01

    Methods based on item response theory (IRT) that can be used to examine differential item functioning (DIF) are illustrated. An IRT-based approach to the detection of DIF was applied to physical function and general distress item sets. DIF was examined with respect to gender, age and race. The method used for DIF detection was the item response theory log-likelihood ratio (IRTLR) approach. DIF magnitude was measured using the differences in the expected item scores, expressed as the unsigned probability differences, and calculated using the non-compensatory DIF index (NCDIF). Finally, impact was assessed using expected scale scores, expressed as group differences in the total test (measure) response functions. The example for the illustration of the methods came from a study of 1,714 patients with cancer or HIV/AIDS. The measure contained 23 items measuring physical functioning ability and 15 items addressing general distress, scored in the positive direction. The substantive findings were of relatively small magnitude DIF. In total, six items showed relatively larger magnitude (expected item score differences greater than the cutoff) of DIF with respect to physical function across the three comparisons: "trouble with a long walk" (race), "vigorous activities" (race, age), "bending, kneeling stooping" (age), "lifting or carrying groceries" (race), "limited in hobbies, leisure" (age), "lack of energy" (race). None of the general distress items evidenced high magnitude DIF; although "worrying about dying" showed some DIF with respect to both age and race, after adjustment. The fact that many physical function items showed DIF with respect to age, even after adjustment for multiple comparisons, indicates that the instrument may be performing differently for these groups. While the magnitude and impact of DIF at the item and scale level was minimal, caution should be exercised in the use of subsets of these items, as might occur with selection for clinical decisions or

  3. A 14-item Mediterranean diet assessment tool and obesity indexes among high-risk subjects: the PREDIMED trial.

    Directory of Open Access Journals (Sweden)

    Miguel Angel Martínez-González

    Full Text Available Independently of total caloric intake, a better quality of the diet (for example, conformity to the Mediterranean diet is associated with lower obesity risk. It is unclear whether a brief dietary assessment tool, instead of full-length comprehensive methods, can also capture this association. In addition to reduced costs, a brief tool has the interesting advantage of allowing immediate feedback to participants in interventional studies. Another relevant question is which individual items of such a brief tool are responsible for this association. We examined these associations using a 14-item tool of adherence to the Mediterranean diet as exposure and body mass index, waist circumference and waist-to-height ratio (WHtR as outcomes.Cross-sectional assessment of all participants in the "PREvención con DIeta MEDiterránea" (PREDIMED trial.7,447 participants (55-80 years, 57% women free of cardiovascular disease, but with either type 2 diabetes or ≥ 3 cardiovascular risk factors. Trained dietitians used both a validated 14-item questionnaire and a full-length validated 137-item food frequency questionnaire to assess dietary habits. Trained nurses measured weight, height and waist circumference.Strong inverse linear associations between the 14-item tool and all adiposity indexes were found. For a two-point increment in the 14-item score, the multivariable-adjusted differences in WHtR were -0.0066 (95% confidence interval, -0.0088 to -0.0049 for women and -0.0059 (-0.0079 to -0.0038 for men. The multivariable-adjusted odds ratio for a WHtR>0.6 in participants scoring ≥ 10 points versus ≤ 7 points was 0.68 (0.57 to 0.80 for women and 0.66 (0.54 to 0.80 for men. High consumption of nuts and low consumption of sweetened/carbonated beverages presented the strongest inverse associations with abdominal obesity.A brief 14-item tool was able to capture a strong monotonic inverse association between adherence to a good quality dietary pattern

  4. A 14-item Mediterranean diet assessment tool and obesity indexes among high-risk subjects: the PREDIMED trial.

    Science.gov (United States)

    Martínez-González, Miguel Angel; García-Arellano, Ana; Toledo, Estefanía; Salas-Salvadó, Jordi; Buil-Cosiales, Pilar; Corella, Dolores; Covas, Maria Isabel; Schröder, Helmut; Arós, Fernando; Gómez-Gracia, Enrique; Fiol, Miquel; Ruiz-Gutiérrez, Valentina; Lapetra, José; Lamuela-Raventos, Rosa Maria; Serra-Majem, Lluís; Pintó, Xavier; Muñoz, Miguel Angel; Wärnberg, Julia; Ros, Emilio; Estruch, Ramón

    2012-01-01

    Independently of total caloric intake, a better quality of the diet (for example, conformity to the Mediterranean diet) is associated with lower obesity risk. It is unclear whether a brief dietary assessment tool, instead of full-length comprehensive methods, can also capture this association. In addition to reduced costs, a brief tool has the interesting advantage of allowing immediate feedback to participants in interventional studies. Another relevant question is which individual items of such a brief tool are responsible for this association. We examined these associations using a 14-item tool of adherence to the Mediterranean diet as exposure and body mass index, waist circumference and waist-to-height ratio (WHtR) as outcomes. Cross-sectional assessment of all participants in the "PREvención con DIeta MEDiterránea" (PREDIMED) trial. 7,447 participants (55-80 years, 57% women) free of cardiovascular disease, but with either type 2 diabetes or ≥ 3 cardiovascular risk factors. Trained dietitians used both a validated 14-item questionnaire and a full-length validated 137-item food frequency questionnaire to assess dietary habits. Trained nurses measured weight, height and waist circumference. Strong inverse linear associations between the 14-item tool and all adiposity indexes were found. For a two-point increment in the 14-item score, the multivariable-adjusted differences in WHtR were -0.0066 (95% confidence interval, -0.0088 to -0.0049) for women and -0.0059 (-0.0079 to -0.0038) for men. The multivariable-adjusted odds ratio for a WHtR>0.6 in participants scoring ≥ 10 points versus ≤ 7 points was 0.68 (0.57 to 0.80) for women and 0.66 (0.54 to 0.80) for men. High consumption of nuts and low consumption of sweetened/carbonated beverages presented the strongest inverse associations with abdominal obesity. A brief 14-item tool was able to capture a strong monotonic inverse association between adherence to a good quality dietary pattern (Mediterranean diet

  5. A 14-Item Mediterranean Diet Assessment Tool and Obesity Indexes among High-Risk Subjects: The PREDIMED Trial

    Science.gov (United States)

    Martínez-González, Miguel Angel; García-Arellano, Ana; Toledo, Estefanía; Salas-Salvadó, Jordi; Buil-Cosiales, Pilar; Corella, Dolores; Covas, Maria Isabel; Schröder, Helmut; Arós, Fernando; Gómez-Gracia, Enrique; Fiol, Miquel; Ruiz-Gutiérrez, Valentina; Lapetra, José; Lamuela-Raventos, Rosa Maria; Serra-Majem, Lluís; Pintó, Xavier; Muñoz, Miguel Angel; Wärnberg, Julia; Ros, Emilio; Estruch, Ramón

    2012-01-01

    Objective Independently of total caloric intake, a better quality of the diet (for example, conformity to the Mediterranean diet) is associated with lower obesity risk. It is unclear whether a brief dietary assessment tool, instead of full-length comprehensive methods, can also capture this association. In addition to reduced costs, a brief tool has the interesting advantage of allowing immediate feedback to participants in interventional studies. Another relevant question is which individual items of such a brief tool are responsible for this association. We examined these associations using a 14-item tool of adherence to the Mediterranean diet as exposure and body mass index, waist circumference and waist-to-height ratio (WHtR) as outcomes. Design Cross-sectional assessment of all participants in the “PREvención con DIeta MEDiterránea” (PREDIMED) trial. Subjects 7,447 participants (55–80 years, 57% women) free of cardiovascular disease, but with either type 2 diabetes or ≥3 cardiovascular risk factors. Trained dietitians used both a validated 14-item questionnaire and a full-length validated 137-item food frequency questionnaire to assess dietary habits. Trained nurses measured weight, height and waist circumference. Results Strong inverse linear associations between the 14-item tool and all adiposity indexes were found. For a two-point increment in the 14-item score, the multivariable-adjusted differences in WHtR were −0.0066 (95% confidence interval, –0.0088 to −0.0049) for women and –0.0059 (–0.0079 to –0.0038) for men. The multivariable-adjusted odds ratio for a WHtR>0.6 in participants scoring ≥10 points versus ≤7 points was 0.68 (0.57 to 0.80) for women and 0.66 (0.54 to 0.80) for men. High consumption of nuts and low consumption of sweetened/carbonated beverages presented the strongest inverse associations with abdominal obesity. Conclusions A brief 14-item tool was able to capture a strong monotonic inverse association between

  6. Assessing the specificity of posttraumatic stress disorder's dysphoric items within the dysphoria model.

    Science.gov (United States)

    Armour, Cherie; Shevlin, Mark

    2013-10-01

    The factor structure of posttraumatic stress disorder (PTSD) currently used by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), has received limited support. A four-factor dysphoria model is widely supported. However, the dysphoria factor of this model has been hailed as a nonspecific factor of PTSD. The present study investigated the specificity of the dysphoria factor within the dysphoria model by conducting a confirmatory factor analysis while statistically controlling for the variance attributable to depression. The sample consisted of 429 individuals who met the diagnostic criteria for PTSD in the National Comorbidity Survey. The results concluded that there was no significant attenuation in any of the PTSD items. This finding is pertinent given several proposals for the removal of dysphoric items from the diagnostic criteria set of PTSD in the upcoming DSM-5.

  7. Are scores on English and French versions of the PHQ-9 comparable? An assessment of differential item functioning.

    Directory of Open Access Journals (Sweden)

    Erin Arthurs

    Full Text Available Medical research increasingly utilizes patient-reported outcome measures administered and scored in different languages. In order to pool or compare outcomes from different language versions, instruments should be measurement equivalent across linguistic groups. The objective of this study was to examine the cross-language measurement equivalence of the Patient Health Questionnaire-9 (PHQ-9 between English- and French-speaking Canadian patients with systemic sclerosis (SSc.The sample consisted of 739 English- and 221 French-speaking SSc patients. Multiple-Indicator Multiple-Cause (MIMIC modeling was used to identify items displaying possible differential item functioning (DIF.A one-factor model for the PHQ-9 fit the data well in both English- and French-speaking samples. Statistically significant DIF was found for 3 of 9 items on the PHQ-9. However, the overall estimate in depression latent scores between English- and French-speaking respondents was not influenced substantively by DIF.Although there were several PHQ-9 items with evidence of minor DIF, there was no evidence that these differences influenced overall scores meaningfully. The PHQ-9 can reasonably be used without adjustment in Canadian English- and French-speaking samples. Analyses assessing measurement equivalence should be routinely conducted prior to pooling data from English and French versions of patient-reported outcome measures.

  8. Negative affectivity and social inhibition in cardiovascular disease: evaluating type-D personality and its assessment using item response theory.

    Science.gov (United States)

    Emons, Wilco H M; Meijer, Rob R; Denollet, Johan

    2007-07-01

    Individuals with increased levels of both negative affectivity (NA) and social inhibition (SI)-referred to as type-D personality-are at increased risk of adverse cardiac events. We used item response theory (IRT) to evaluate NA, SI, and type-D personality as measured by the DS14. The objectives of this study were (a) to evaluate the relative contribution of individual items to the measurement precision at the cutoff to distinguish type-D from non-type-D personality and (b) to investigate the comparability of NA, SI, and type-D constructs across the general population and clinical populations. Data from representative samples including 1316 respondents from the general population, 427 respondents diagnosed with coronary heart disease, and 732 persons suffering from hypertension were analyzed using the graded response IRT model. In Study 1, the information functions obtained in the IRT analysis showed that (a) all items had highest measurement precision around the cutoff and (b) items are most informative at the higher end of the scale. In Study 2, the IRT analysis showed that measurements were fairly comparable across the general population and clinical populations. The DS14 adequately measures NA and SI, with highest reliability in the trait range around the cutoff. The DS14 is a valid instrument to assess and compare type-D personality across clinical groups.

  9. Barriers and benefits to desired behaviors for single use plastic items in northeast Ohio's Lake Erie basin.

    Science.gov (United States)

    Bartolotta, Jill F; Hardy, Scott D

    2018-02-01

    Given the growing saliency of plastic marine debris, and the impact of plastics on beaches and aquatic environments in the Laurentian Great Lakes, applied research is needed to support municipal and nongovernmental campaigns to prevent debris from reaching the water's edge. This study addresses this need by examining the barriers and benefits to positive behavior for two plastic debris items in northeast Ohio's Lake Erie basin: plastic bags and plastic water bottles. An online survey is employed to gather data on the use and disposal of these plastic items and to solicit recommendations on how to positively change behavior to reduce improper disposal. Results support a ban on plastic bags and plastic water bottles, with more enthusiasm for a bag ban. Financial incentives are also seen as an effective way to influence behavior change, as are location-specific solutions focused on education and outreach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. The influence of item order on intentional response distortion in the assessment of high potentials: assessing pilot applicants.

    Science.gov (United States)

    Khorramdel, Lale; Kubinger, Klaus D; Uitz, Alexander

    2014-04-01

    An experiment was conducted to investigate the effects of item order and questionnaire content on faking good or intentional response distortion. It was hypothesized that intentional response distortion would either increase towards the end of a long questionnaire, as learning effects might make it easier to adjust responses to a faking good schema, or decrease because applicants' will to distort responses is reduced if the questionnaire lasts long enough. Furthermore, it was hypothesized that certain types of questionnaire content are especially vulnerable to response distortion. Eighty-four pre-selected pilot applicants filled out a questionnaire consisting of 516 items including items from the NEO five factor inventory (NEO FFI), NEO personality inventory revised (NEO PI-R) and business-focused inventory of personality (BIP). The positions of the items were varied within the applicant sample to test if responses are affected by item order, and applicants' response behaviour was additionally compared to that of volunteers. Applicants reported significantly higher mean scores than volunteers, and results provide some evidence of decreased faking tendencies towards the end of the questionnaire. Furthermore, it could be demonstrated that lower variances or standard deviations in combination with appropriate (often higher) mean scores can serve as an indicator for faking tendencies in group comparisons, even if effects are not significant. © 2013 International Union of Psychological Science.

  11. Performance of the biological rhythms interview for assessment in neuropsychiatry: An item response theory and actigraphy analysis.

    Science.gov (United States)

    Allega, Olivia R; Leng, Xiamin; Vaccarino, Anthony; Skelly, Matthew; Lanzini, Mariana; Hidalgo, Maria Paz; Soares, Claudio N; Kennedy, Sidney H; Frey, Benicio N

    2018-01-01

    Biological rhythm disturbances are widely associated with the pathophysiology of mood disorders. The Biological Rhythms Interview for Assessment in Neuropsychiatry (BRIAN) is a self-report that indexes rhythm disturbance in sleep, activity, social and eating patterns. The aim of this study was to perform an Item Response Theory (IRT) analysis of the BRIAN and investigate its associations with objective sleep and rhythm disturbance measures. 103 subjects (31 bipolar, 32 major depression and 40 healthy volunteers) wore an actiwatch for fifteen days, and completed a first morning urine sample and the BRIAN on day 15. IRT analysis assessed individual BRIAN items and their relationship to total score. Individual actiwatch records were processed to produce a sequence of transitions between rest/activity, and a likelihood of transitioning between states was calculated to investigate sleep-wake dynamics. Cosinor analysis produced daily activity rhythms (DARs). Spearman correlations were used to assess the association between sleep/DAR variables and the BRIAN. IRT analyses showed that 11 of 18 BRIAN items displayed a high level of discrimination between item options across a range of BRIAN total scores. Total BRIAN score correlated with wake after sleep onset, total activity count during sleep, and urinary 6-sulphatoxymelatonin. BRIAN Activity domain correlated with the daytime transition probability from rest to activity. The sample size may have been underpowered for the graded-response model employed in IRT. The study lacked an objective comparison for BRIAN eating and social domain. The present study reveals the BRIAN displays promising external validity compared to objective parameters of circadian rhythmicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. A Structural Assessment of the 30-Item Metacognitions Questionnaire for Children and Its Relations to Anxiety Symptoms

    DEFF Research Database (Denmark)

    Esbjørn, Barbara Hoff; Sømhovd, Mikael Julius; Holm, Jon Måløv

    2013-01-01

    Theoretical models of anxiety have been developed in adult populations. The applicability of these models in child samples has been assessed using downward extensions of the questionnaires developed to assess the proposed theoretical mechanisms. This poses a challenge, as children are still...... in the process of developing the skills that are being assessed. Psychometrically sound assessment tools are therefore needed for this developing population, in order to ensure the early detection of mechanisms leading to anxiety disorders in children. This study examined if metacognitions, which play a key role...... in generalized anxiety disorder (GAD) in adults, can also be reliably assessed in childhood. The study investigated the psychometric properties of the 30-item Metacognitions Questionnaire for Children (MCQ-C₃₀; Gerlach, Adam, Marschke, & Melfsen, 2008) in a national sample of 974 children and adolescents (538...

  13. Passive ultra high frequency radio frequency identification systems for single-item identification in food supply chains

    Directory of Open Access Journals (Sweden)

    Paolo Barge

    2017-02-01

    Full Text Available In the food industry, composition, size, and shape of items are much less regular than in other commodities sectors. In addition, a wide variety of packaging, composed by different materials, is employed. As material, size and shape of items to which the tag should be attached strongly influence the minimum power requested for tag functioning, performance improvements can be achieved only selecting suitable radio frequency (RF identifiers for the specific combination of food product and packaging. When dealing with logistics units, the dynamic reading of a vast number of tags could originate simultaneous broadcasting of signals (tag-to-tag collisions that could affect reading rates and the overall reliability of the identification procedure. This paper reports the results of an analysis of the reading performance of ultra high frequency radio frequency identification systems for multiple static and dynamic electronic identification of food packed products in controlled conditions. Products were considered when arranged on a logistics pallet. The effects on reading rate of different factors, among which the product type, the gate configuration, the field polarisation, the power output of the RF reader, the interrogation protocol configuration as well as the transit speed, the number of tags and their interactions were statistically analysed and compared.

  14. Assessing the discriminating power of item and test scores in the linear factor-analysis model

    Directory of Open Access Journals (Sweden)

    Pere J. Ferrando

    2012-01-01

    Full Text Available Las propuestas rigurosas y basadas en un modelo psicométrico para estudiar el impreciso concepto de "capacidad discriminativa" son escasas y generalmente limitadas a los modelos no-lineales para items binarios. En este artículo se propone un marco general para evaluar la capacidad discriminativa de las puntuaciones en ítems y tests que son calibrados mediante el modelo de un factor común. La propuesta se organiza en torno a tres criterios: (a tipo de puntuación, (b rango de discriminación y (c aspecto específico que se evalúa. Dentro del marco propuesto: (a se discuten las relaciones entre 16 medidas, de las cuales 6 parecen ser nuevas, y (b se estudian las relaciones entre ellas. La utilidad de la propuesta en las aplicaciones psicométricas que usan el modelo factorial se ilustra mediante un ejemplo empírico.

  15. 'Do you think you suffer from depression?' Reevaluating the use of a single item question for the screening of depression in older primary care patients

    DEFF Research Database (Denmark)

    Ayalon, Liat; Goldfracht, Margalit; Bech, Per

    2010-01-01

    to existing depression screening tools. METHODS: A cross sectional sample of 153 older primary care patients. Participants completed several depression-screening measures (e.g. a single depression screen, Patient Health Questionnaire-9, Major Depression Inventory, Visual Analogue Scale). Measures were...... evaluated against a depression diagnosis made by the Structured Clinical Interview for DSM-IV. RESULTS: Overall, 3.9% of the sample was diagnosed with depression. The most notable finding was that the single-item question, 'do you think you suffer from depression?' had as good or better sensitivity (83......: An easy way to detect depression in older primary care patients would be asking the single question, 'do you think you suffer from depression?'...

  16. Development of a simple 12-item theory-based instrument to assess the impact of continuing professional development on clinical behavioral intentions.

    Science.gov (United States)

    Légaré, France; Borduas, Francine; Freitas, Adriana; Jacques, André; Godin, Gaston; Luconi, Francesca; Grimshaw, Jeremy

    2014-01-01

    Decision-makers in organizations providing continuing professional development (CPD) have identified the need for routine assessment of its impact on practice. We sought to develop a theory-based instrument for evaluating the impact of CPD activities on health professionals' clinical behavioral intentions. Our multipronged study had four phases. 1) We systematically reviewed the literature for instruments that used socio-cognitive theories to assess healthcare professionals' clinically-oriented behavioral intentions and/or behaviors; we extracted items relating to the theoretical constructs of an integrated model of healthcare professionals' behaviors and removed duplicates. 2) A committee of researchers and CPD decision-makers selected a pool of items relevant to CPD. 3) An international group of experts (n = 70) reached consensus on the most relevant items using electronic Delphi surveys. 4) We created a preliminary instrument with the items found most relevant and assessed its factorial validity, internal consistency and reliability (weighted kappa) over a two-week period among 138 physicians attending a CPD activity. Out of 72 potentially relevant instruments, 47 were analyzed. Of the 1218 items extracted from these, 16% were discarded as improperly phrased and 70% discarded as duplicates. Mapping the remaining items onto the constructs of the integrated model of healthcare professionals' behaviors yielded a minimum of 18 and a maximum of 275 items per construct. The partnership committee retained 61 items covering all seven constructs. Two iterations of the Delphi process produced consensus on a provisional 40-item questionnaire. Exploratory factorial analysis following test-retest resulted in a 12-item questionnaire. Cronbach's coefficients for the constructs varied from 0.77 to 0.85. A 12-item theory-based instrument for assessing the impact of CPD activities on health professionals' clinical behavioral intentions showed adequate validity and reliability

  17. Development of a simple 12-item theory-based instrument to assess the impact of continuing professional development on clinical behavioral intentions.

    Directory of Open Access Journals (Sweden)

    France Légaré

    Full Text Available Decision-makers in organizations providing continuing professional development (CPD have identified the need for routine assessment of its impact on practice. We sought to develop a theory-based instrument for evaluating the impact of CPD activities on health professionals' clinical behavioral intentions.Our multipronged study had four phases. 1 We systematically reviewed the literature for instruments that used socio-cognitive theories to assess healthcare professionals' clinically-oriented behavioral intentions and/or behaviors; we extracted items relating to the theoretical constructs of an integrated model of healthcare professionals' behaviors and removed duplicates. 2 A committee of researchers and CPD decision-makers selected a pool of items relevant to CPD. 3 An international group of experts (n = 70 reached consensus on the most relevant items using electronic Delphi surveys. 4 We created a preliminary instrument with the items found most relevant and assessed its factorial validity, internal consistency and reliability (weighted kappa over a two-week period among 138 physicians attending a CPD activity. Out of 72 potentially relevant instruments, 47 were analyzed. Of the 1218 items extracted from these, 16% were discarded as improperly phrased and 70% discarded as duplicates. Mapping the remaining items onto the constructs of the integrated model of healthcare professionals' behaviors yielded a minimum of 18 and a maximum of 275 items per construct. The partnership committee retained 61 items covering all seven constructs. Two iterations of the Delphi process produced consensus on a provisional 40-item questionnaire. Exploratory factorial analysis following test-retest resulted in a 12-item questionnaire. Cronbach's coefficients for the constructs varied from 0.77 to 0.85.A 12-item theory-based instrument for assessing the impact of CPD activities on health professionals' clinical behavioral intentions showed adequate validity and

  18. Value in Single-level Lumbar Discectomy: Surgical Disposable Item Cost and Relationship to Patient-reported Outcomes.

    Science.gov (United States)

    Rosenbaum, Benjamin P; Modic, Michael T; Krishnaney, Ajit A

    2017-11-01

    This is a retrospective study. Compare improvements in health status measures (HSMs) and surgical costs to determine whether use of more costly items has any relationship to clinical outcome and value in lumbar disc surgery. Association between cost, outcomes, and value in spine surgery, including lumbar discectomy is poorly understood. Outcomes were calculated as difference in mean HSM scores between preoperative and postoperative timeframes. Prospective validated patient-reported HSMs studied were EuroQol quality of life index score (EQ-5D), Pain Disability Questionnaire (PDQ), and Patient Health Questionnaire (PHQ-9). Surgical costs consisted of disposable items and implants used in operating room. We retrospectively identified all adult patients at Cleveland Clinic main campus between October 2009 and August 2013 who underwent lumbar discectomy (652) using administrative billing data, Current Procedural Terminology (CPT) code 63030. HSMs were obtained from Cleveland Clinic Knowledge Program Data Registry. In total, 67% of operations performed in the outpatient or ambulatory setting, 33% in the inpatient setting. Among 9 surgeons who performed >10 lumbar discectomies, there were 72.4 operations per surgeon, on average. Mean surgical costs of each surgeon differed (Pcosts (Pcosts (P=0.76, 0.07, 0.76, respectively). In multivariable regression, only surgical cost was significantly correlated to mean difference in PDQ (P=0.030). More costly surgeries resulted in worse PDQ outcomes. Mean surgical costs varied statistically among 9 surgeons; costs were not shown to be positively correlated with patient outcomes. Performing an operation using more costly disposable supplies/implants does not seem to improve patient outcomes and should be considered when constructing preference cards and during an operation.

  19. 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.

  20. [Assessment of criminal responsibility in paraphilic disorder. Can the severity of the disorder be assessed with items of standardized prognostic instruments?].

    Science.gov (United States)

    Briken, P; Müller, J L

    2014-03-01

    Assessment of the severity of paraphilic disorders is an important aspect of psychiatric court reports for assessing criminal responsibility and placement in a forensic psychiatric hospital according to the German penal code (§§ 20, 21, 63 StGB). The minimum requirements for appraisal of criminal responsibility published by an interdisciplinary working group under the guidance of the German Federal Court of Justice define the standards for this procedure. This paper presents a research concept that aims to assess the severity of paraphilic disorders by using items of standardized prognostic instruments. In addition to a formal diagnosis according to the international classification of diseases (ICD) and the diagnostic and statistical manual of mental diseases (DSM) criteria, the items "deviant sexual interests" and "sexual preoccupations" from the prognosis instrument Stable 2007 are used to assess the severity of paraphilic disorders. Other criteria, such as "relationship deficits" are used to support the appraisal of the severity of the disorder. The items "sexual preoccupation", "emotional collapse" and "collapse of social support" from the prognosis instrument Acute 2007 are used to assess the capacity for self-control. In a next step the validity and reliability of this concept will be tested.

  1. Assessing Model Characterization of Single Source ...

    Science.gov (United States)

    Aircraft measurements made downwind from specific coal fired power plants during the 2013 Southeast Nexus field campaign provide a unique opportunity to evaluate single source photochemical model predictions of both O3 and secondary PM2.5 species. The model did well at predicting downwind plume placement. The model shows similar patterns of an increasing fraction of PM2.5 sulfate ion to the sum of SO2 and PM2.5 sulfate ion by distance from the source compared with ambient based estimates. The model was less consistent in capturing downwind ambient based trends in conversion of NOX to NOY from these sources. Source sensitivity approaches capture near-source O3 titration by fresh NO emissions, in particular subgrid plume treatment. However, capturing this near-source chemical feature did not translate into better downwind peak estimates of single source O3 impacts. The model estimated O3 production from these sources but often was lower than ambient based source production. The downwind transect ambient measurements, in particular secondary PM2.5 and O3, have some level of contribution from other sources which makes direct comparison with model source contribution challenging. Model source attribution results suggest contribution to secondary pollutants from multiple sources even where primary pollutants indicate the presence of a single source. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, deci

  2. Development of coordination system model on single-supplier multi-buyer for multi-item supply chain with probabilistic demand

    Science.gov (United States)

    Olivia, G.; Santoso, A.; Prayogo, D. N.

    2017-11-01

    Nowadays, the level of competition between supply chains is getting tighter and a good coordination system between supply chains members is very crucial in solving the issue. This paper focused on a model development of coordination system between single supplier and buyers in a supply chain as a solution. Proposed optimization model was designed to determine the optimal number of deliveries from a supplier to buyers in order to minimize the total cost over a planning horizon. Components of the total supply chain cost consist of transportation costs, handling costs of supplier and buyers and also stock out costs. In the proposed optimization model, the supplier can supply various types of items to retailers whose item demand patterns are probabilistic. Sensitivity analysis of the proposed model was conducted to test the effect of changes in transport costs, handling costs and production capacities of the supplier. The results of the sensitivity analysis showed a significant influence on the changes in the transportation cost, handling costs and production capacity to the decisions of the optimal numbers of product delivery for each item to the buyers.

  3. Multilevel Item Response Modeling: Applications to Large-Scale Assessment of Academic Achievement

    Science.gov (United States)

    Zheng, Xiaohui

    2009-01-01

    The call for standards-based reform and educational accountability has led to increased attention to large-scale assessments. Over the past two decades, large-scale assessments have been providing policymakers and educators with timely information about student learning and achievement to facilitate their decisions regarding schools, teachers and…

  4. Neonatal Facial Coding System for Assessing Postoperative Pain in Infants: Item Reduction is Valid and Feasible

    NARCIS (Netherlands)

    Peters, J.W.B.; Koot, H.M.; Grunau, R.E.; Boer, J. de; Druenen, M.J. van; Tibboel, D.; Duivenvoorden, H.J.

    2003-01-01

    Objective: The objectives of this study were to: (1) evaluate the validity of the Neonatal Facial Coding System (NFCS) for assessment of postoperative pain and (2) explore whether the number of NFCS facial actions could be reduced for assessing postoperative pain. Design: Prospective, observational

  5. The Dimensional Assessment of Personality Psychopathology Basic Questionnaire: shortened versions item analysis.

    Science.gov (United States)

    Aluja, Anton; Blanch, Àngel; Blanco, Eduardo; Martí-Guiu, Maite; Balada, Ferran

    2015-01-13

    This study has been designed to evaluate and replicate the psychometric properties of the Dimensional Assessment of Personality Psychopathology-Basic Questionnaire (DAPP-BQ) and the DAPP-BQ short form (DAPP-SF) in a large Spanish general population sample. Additionally, we have generated a reduced form called DAPP-90, using a strategy based on a structural equation modeling (SEM) methodology in two independent samples, a calibration and a validation sample. The DAPP-90 scales obtained a more satisfactory fit on SEM adjustment values (average: TLI > .97 and RMSEA assessment of patients in hospital consultation or in brief psychological assessments.

  6. Psychometric Properties and Responsiveness to Change of 15- and 28-Item Versions of the SCORE: A Family Assessment Questionnaire.

    Science.gov (United States)

    Hamilton, Elena; Carr, Alan; Cahill, Paul; Cassells, Ciara; Hartnett, Dan

    2015-09-01

    The SCORE (Systemic Clinical Outcome and Routine Evaluation) is a 40-item questionnaire for completion by family members 12 years and older to assess outcome in systemic therapy. This study aimed to investigate psychometric properties of two short versions of the SCORE and their responsiveness to therapeutic change. Data were collected at 19 centers from 701 families at baseline and from 433 of these 3-5 months later. Results confirmed the three-factor structure (strengths, difficulties, and communication) of the 15- and 28-item versions of the SCORE. Both instruments had good internal consistency and test-retest reliability. They also showed construct and criterion validity, correlating with measures of parent, child, and family adjustment, and discriminating between clinical and nonclinical cases. Total and factor scales of the SCORE-15 and -28 were responsive to change over 3-5 months of therapy. The SCORE-15 and SCORE-28 are brief psychometrically robust family assessment instruments which may be used to evaluate systemic therapy. © 2015 Family Process Institute.

  7. An approach for estimating item sensitivity to within-person change over time: An illustration using the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog).

    Science.gov (United States)

    Dowling, N Maritza; Bolt, Daniel M; Deng, Sien

    2016-12-01

    When assessments are primarily used to measure change over time, it is important to evaluate items according to their sensitivity to change, specifically. Items that demonstrate good sensitivity to between-person differences at baseline may not show good sensitivity to change over time, and vice versa. In this study, we applied a longitudinal factor model of change to a widely used cognitive test designed to assess global cognitive status in dementia, and contrasted the relative sensitivity of items to change. Statistically nested models were estimated introducing distinct latent factors related to initial status differences between test-takers and within-person latent change across successive time points of measurement. Models were estimated using all available longitudinal item-level data from the Alzheimer's Disease Assessment Scale-Cognitive subscale, including participants representing the full-spectrum of disease status who were enrolled in the multisite Alzheimer's Disease Neuroimaging Initiative. Five of the 13 Alzheimer's Disease Assessment Scale-Cognitive items demonstrated noticeably higher loadings with respect to sensitivity to change. Attending to performance change on only these 5 items yielded a clearer picture of cognitive decline more consistent with theoretical expectations in comparison to the full 13-item scale. Items that show good psychometric properties in cross-sectional studies are not necessarily the best items at measuring change over time, such as cognitive decline. Applications of the methodological approach described and illustrated in this study can advance our understanding regarding the types of items that best detect fine-grained early pathological changes in cognition. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  8. Examination of validity of fall risk assessment items for screening high fall risk elderly among the healthy community-dwelling Japanese population

    OpenAIRE

    DEMURA, Shinichi; SATO, Susumu; YAMAJI, Shunsuke; KASUGA, Kosho; NAGASAWA, Yoshinori

    2010-01-01

    We aimed to examine the validity of fall risk assessment items for the healthy community-dwelling elderly Japanese population. Participants were 1122 healthy elderly individuals aged 60 years and over (380 males and 742 females). The percentage who had experienced a fall was 15.8%. This study used fall experience and 50 fall risk assessment items representing the five risk factors (symptoms of falling, physical function, disease and physical symptom, environment, and behavior and character), ...

  9. e-GovQual: A Multiple-Item Scale for Assessing e-Government Service Quality

    Science.gov (United States)

    Papadomichelaki, Xenia; Mentzas, Gregoris

    2012-01-01

    A critical element in the evolution of governmental services through the internet is the development of sites that better serve the citizens' needs. To deliver superior service quality, we must first understand how citizens perceive and evaluate online. Citizen assessment is built on defining quality, identifying underlying dimensions, and…

  10. Psychometrical Assessment and Item Analysis of the General Health Questionnaire in Victims of Terrorism

    Science.gov (United States)

    Delgado-Gomez, David; Lopez-Castroman, Jorge; de Leon-Martinez, Victoria; Baca-Garcia, Enrique; Cabanas-Arrate, Maria Luisa; Sanchez-Gonzalez, Antonio; Aguado, David

    2013-01-01

    There is a need to assess the psychiatric morbidity that appears as a consequence of terrorist attacks. The General Health Questionnaire (GHQ) has been used to this end, but its psychometric properties have never been evaluated in a population affected by terrorism. A sample of 891 participants included 162 direct victims of terrorist attacks and…

  11. Using a single question to assess physical activity in older adults: a reliability and validity study

    Directory of Open Access Journals (Sweden)

    Gill Dawn P

    2012-02-01

    Full Text Available Abstract Background Single-item physical activity questions provide a quick approximation of physical activity levels. While recall questionnaires provide a more detailed picture of an individual's level of physical activity, single-item questions may be more appropriate in certain situations. The aim of this study was to evaluate two single-item physical activity questions (one absolute question and one relative question for test-retest reliability, convergent validity, and discriminant validity, in a sample of older adults. Methods Data was obtained from the Project to Prevent Falls in Veterans, a fall risk-factor screening and modification trial. One question measured absolute physical activity (seldom, moderately, vigorously active and one measured relative physical activity (more, about as, less active than peers. Test-retest reliability was examined using weighted Kappa statistics (κ in a sample of 43 subjects. Validity was assessed using correlation coefficients (r in participants who received clinical assessments (n = 159. Results The absolute physical activity question was more reliable than the relative physical activity question (κ = 0.75 vs. κ = 0.56. Convergent validity, however, was stronger for the relative physical activity question (r = 0.28 to 0.57 vs. r = 0.10 to 0.33. Discriminant validity was similar for both questions. For the relative physical activity question, there was moderate agreement when this question was re-administered seven days later, fair to moderate/good associations when compared with indicators of physical function, and little to no associations when compared with measures hypothesized to be theoretically not related to physical activity. Conclusions The relative physical activity question had the best combination of test-retest reliability, convergent validity and discriminant validity. In studies requiring a measure of physical activity, where physical activity is not the primary focus and more

  12. Assessing cross-cultural item bias in questionnaires : Acculturation and the Measurement of Social Support and Family Cohesion for Adolescents

    NARCIS (Netherlands)

    Hemert, Dianne A. van; Baerveldt, Chris; Vermande, Marjolijn

    2001-01-01

    Amethod is presented for evaluating the presence and size of cross-cultural item biases. The examined items concern parental support and family cohesion in a Likert-type questionnaire for adolescents in The Netherlands. Each evaluated item has two versions, a collectivist and an individualistic one,

  13. OPTIONS FOR THE ASSESSMENT OF ITEMS OF FINANCIAL STATEMENTS AT NATIONAL, EUROPEAN AND INTERNATIONAL LEVEL

    Directory of Open Access Journals (Sweden)

    SILVIA SAMARA

    2010-01-01

    Full Text Available The main purpose of evaluation is to determine the financial position and the outcome of the entity’s activity. With the intensification of the phenomena of globalization of economies and financial markets and the emergence of phenomena such as inflation, it began to be more often used the assessment based on the current value and, in particular, on the fair value. The users of the financial statements must always be taken into when selecting a basis of evaluation. Internationally, we can observe the tendency that, by the use of a certain bases of evaluation, to respond favourably to the needs of a various range of users; a balance must be assured between the relevance of the information (their usefulness in decision-making and their reliability (their objectivity.

  14. Complement or Contamination: A Study of the Validity of Multiple-Choice Items when Assessing Reasoning Skills in Physics

    OpenAIRE

    Anders Jönsson; David Rosenlund; Fredrik Alvén

    2017-01-01

    The purpose of this study is to investigate the validity of using multiple-choice (MC) items as a complement to constructed-response (CR) items when making decisions about student performance on reasoning tasks. CR items from a national test in physics have been reformulated into MC items and students’ reasoning skills have been analyzed in two substudies. In the first study, 12 students answered the MC items and were asked to explain their answers orally. In the second study, 102 students fr...

  15. The use of an item response theory-based disability item bank across diseases: accounting for differential item functioning.

    Science.gov (United States)

    Weisscher, Nadine; Glas, Cees A; Vermeulen, Marinus; De Haan, Rob J

    2010-05-01

    There is not a single universally accepted activity of daily living (ADL) instrument available to compare disability assessments across different patient groups. We developed a generic item bank of ADL items using item response theory, the Academic Medical Center Linear Disability Scale (ALDS). When comparing outcomes of the ALDS between patients groups, item characteristics of the ALDS should be comparable across groups. The aim of the study was to assess the differential item functioning (DIF) in a group of patients with various disorders to investigate the comparability across these groups. Cross-sectional, multicenter study including 1,283 in- and outpatients with a variety of disorders and disability levels. The sample was divided in two groups: (1) mainly neurological patients (n=497; vascular medicine, Parkinson's disease and neuromuscular disorders) and (2) patients from internal medicine (n=786; pulmonary diseases, chronic pain, rheumatoid arthritis, and geriatric patients). Eighteen of 72 ALDS items showed statistically significant DIF (P<0.01). However, the DIF could effectively be modeled by the introduction of disease-specific parameters. In the subgroups studied, DIF could be modeled in such a way that the ensemble of the items comprised a scale applicable in both groups.

  16. Proposta de um instrumento de medida para avaliar a satisfação de clientes de bancos utilizando a Teoria da Resposta ao Item Proposal of tool to assess the satisfaction of bank customers using the Item Response Theory

    Directory of Open Access Journals (Sweden)

    Alceu Balbim Junior

    2011-01-01

    Full Text Available Este artigo apresenta um instrumento de medida para avaliação da satisfação de clientes de bancos utilizando a Teoria da Resposta ao Item (TRI. Satisfazer os clientes tem sido uma busca constante das organizações que procuram manterem-se competitivas no mercado. Estudos constatam a relação entre a qualidade percebida pelos clientes, a satisfação e fidelidade. A avaliação da satisfação pode ser realizada por meio da qualidade percebida pelos clientes e a construção de ferramentas de avaliação deve contemplar características específicas da atividade em questão. Embasando-se em artigos que avaliam a satisfação de clientes de bancos, propõe-se um instrumento formado por 29 itens. Os itens foram aplicados a 240 clientes a fim de avaliar a satisfação com o banco de maior relacionamento. Utilizando a Teoria da Resposta ao Item, foram identificados os parâmetros dos itens e a curva de informação. A análise do grau de discriminação dos itens indicou que todos são apropriados. A curva de informação obtida evidenciou o intervalo no qual o instrumento apresenta melhores estimativas para níveis de satisfação. O trabalho apresentou o nível médio de satisfação da amostra e a concentração de clientes nos diferentes níveis de satisfação da escala.This paper presents a model for assessing the satisfaction of bank customers using the Item Response Theory (IRT. Organizations are constantly making effort to satisfy customers seeking to remain competitive. Several studies have reported on the relationship between perceived quality, satisfaction, and loyalty. The assessment of satisfaction can be accomplished through the perceived quality, and the development of assessment tools should address specific features of the activity in question. Based on articles that assess the satisfaction of bank customers, this study proposes an assessment tool consisting of 29 items. The items were applied to 240 clients to assess their

  17. Bipolar Items

    Directory of Open Access Journals (Sweden)

    Nishiguchi Sumiyo

    2016-12-01

    Full Text Available This article asserts that the Japanese wide-scope mo ‘even’ in simple sentences are bipolar items (BPIs antilicensed or forbidden by negation and licensed in a non-monotonic (NM environment. BPIs share the features of negative polarity items (NPIs as well as positive polarity items (PPIs. The Dutch ooit ‘ever’, the Serbo-Croatian i-series ‘and/even’, and the Hungarian is-series ‘and/even’ are antilicensed by clausemate negation and licensed by extraclausal negation (van der Wouden, 1997; Progovac, 1994; Szabolcsi, 2002 or non-monotonic negative (and positive, for Serbo-Croatian emotive predicates. Adding an NPI rescues BPIs in uncomfortable clausemate negation.

  18. Using Procedure Based on Item Response Theory to Evaluate Classification Consistency Indices in the Practice of Large-Scale Assessment

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    Shanshan Zhang

    2017-09-01

    Full Text Available In spite of the growing interest in the methods of evaluating the classification consistency (CC indices, only few researches are available in the field of applying these methods in the practice of large-scale educational assessment. In addition, only few studies considered the influence of practical factors, for example, the examinee ability distribution, the cut score location and the score scale, on the performance of CC indices. Using the newly developed Lee's procedure based on the item response theory (IRT, the main purpose of this study is to investigate the performance of CC indices when practical factors are taken into consideration. A simulation study and an empirical study were conducted under comprehensive conditions. Results suggested that with negatively skewed distribution, the CC indices were larger than with other distributions. Interactions occurred among ability distribution, cut score location, and score scale. Consequently, Lee's IRT procedure is reliable to be used in the field of large-scale educational assessment, and when reporting the indices, it should be treated with caution as testing conditions may vary a lot.

  19. Short Scales for the Assessment of Personality Traits: Development and Validation of the Portuguese Ten-Item Personality Inventory (TIPI

    Directory of Open Access Journals (Sweden)

    Andreia Nunes

    2018-04-01

    Full Text Available The importance of quickly assessing personality traits in many studies prompted the development of brief scales such as the Ten-Item Personality Inventory (TIPI, a measure of five personality traits (extraversion, agreeableness, conscientiousness, emotional stability, and openness. In the current study, we present the Portuguese version of TIPI and examine its psychometric properties, based on a sample of 333 Portuguese adults aged 18 to 65 years. The results revealed reliability coefficients similar to the original version (α = 0.39–0.72, very good 4-week test–retest reliability (n = 81, rs > 0.71, expected factorial structure, high convergent validity with the Big-Five Inventory (rs > 0.60, and correlations with self-esteem, affect, and aggressiveness similar to those found with standard measures of personality traits. Overall, our findings suggest that the Portuguese TIPI is a reliable and valid alternative to longer measures: it offers a promising tool for research contexts in which the available time for personality assessment is highly limited.

  20. A Third-Order Item Response Theory Model for Modeling the Effects of Domains and Subdomains in Large-Scale Educational Assessment Surveys

    Science.gov (United States)

    Rijmen, Frank; Jeon, Minjeong; von Davier, Matthias; Rabe-Hesketh, Sophia

    2014-01-01

    Second-order item response theory models have been used for assessments consisting of several domains, such as content areas. We extend the second-order model to a third-order model for assessments that include subdomains nested in domains. Using a graphical model framework, it is shown how the model does not suffer from the curse of…

  1. Assessing psychopathy among justice involved adolescents with the PCL:YV: an item response theory examination across gender.

    Science.gov (United States)

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

    2015-01-01

    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 4 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 4 PCL: YV items function differently between boys and girls. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  2. Comparison of single questions and brief questionnaire with longer validated food frequency questionnaire to assess adequate fruit and vegetable intake.

    Science.gov (United States)

    Cook, Amelia; Roberts, Kia; O'Leary, Fiona; Allman-Farinelli, Margaret Anne

    2015-01-01

    The aim of this study was to determine if a single question (SQ) for fruit and a SQ or five-item questionnaire for vegetable consumption (VFQ) could replace a longer food frequency questionnaire (FFQ) to screen for inadequate versus adequate intakes in populations. Participants (109) completed three test screeners: fruit SQ, vegetable SQ, and a five-item VFQ followed by the reference 74-item FFQ (version 2 of the Dietary Questionnaire for Epidemiological Studies [DQESv2]) including 13 fruit and 25 vegetable items. The five-item VFQ asked about intake of salad vegetables, cooked vegetables, white potatoes, legumes, and vegetable juice. The screeners were compared with the reference (DQESv2 FFQ) for sensitivity, specificity, and positive and negative predictive powers (PPV, NPV) to detect intakes of two or more servings of fruit and three or more servings of vegetables. Relative validity was examined using Bland-Altman statistics. The fruit SQ showed a PPV of 56% and an NPV of 83%. The PPV for the vegetable SQ was 30% and the NPV was 89%. For the five-item VFQ, the PPV was 39% and the NPV was 85%. Bland-Altman plots and linear regression equations showed that although the screener showed good agreement for fruit (unstandardized b1 coefficient = 0.04) for vegetable intake the difference between methods increased at higher intake levels (unstandardized b1 coefficients = -0.3 for the SQ, b1 = -0.6 for five-item VFQ). The fruit SQ and the five-item VFQ are suitable replacements for longer FFQs to detect inadequate intake and assess population mean but not individual intakes. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. A study of the psychometric properties of 12-item World Health Organization Disability Assessment Schedule 2.0 in a large population of people with chronic musculoskeletal pain.

    Science.gov (United States)

    Saltychev, Mikhail; Bärlund, Esa; Mattie, Ryan; McCormick, Zachary; Paltamaa, Jaana; Laimi, Katri

    2017-02-01

    To assess the validity of the Finnish translation of the 12-item World Health Organization Disability Assessment Schedule (WHODAS 2.0). Cross-sectional cohort survey study. Physical and Rehabilitation Medicine outpatient university clinic. The 501 consecutive patients with chronic musculoskeletal pain. Exploratory factor analysis and a graded response model using item response theory analysis were used to assess the constructs and discrimination ability of WHODAS 2.0. The exploratory factor analysis revealed two retained factors with eigenvalues 5.15 and 1.04. Discrimination ability of all items was high or perfect, varying from 1.2 to 2.5. The difficulty levels of seven out of 12 items were shifted towards the elevated disability level. As a result, the entire test characteristic curve showed a shift towards higher levels of disability, placing it at the point of disability level of +1 (where 0 indicates the average level of disability within the sample). The present data indicate that the Finnish translation of the 12-item WHODAS 2.0 is a valid instrument for measuring restrictions of activity and participation among patients with chronic musculoskeletal pain.

  4. Identification of Key Items Regarding Personality, Environment, and Life Events to Assess Risk and Resilience Factors for Harmful Alcohol Drinking in Adolescents.

    Science.gov (United States)

    Heinrich, Angela; Schumann, Gunter; Flor, Herta; Nees, Frauke

    2016-11-01

    Alcohol misuse often develops during adolescence involving interacting factors deriving from personality, environment and life events that can be assessed with well-established instruments. However, for specific research purposes, involving the assessment of large data sets, it may be beneficial having a short tool of key items representing the most important risk factors. We identified a set of key items from standard questionnaires assessed in about 2000 adolescents. In our longitudinal study we identified important items on personality, environment, and life events explaining alcohol drinking behaviour at the age of 14 years and the increase of alcohol consumption 2 years later. The key items explained 33.4% of variance in alcohol drinking behaviour (vs. 34.8% for original battery) and can be completed in six minutes. Our item list represents a powerful easy-to-use tool for the examination of alcohol drinking behaviour in adolescents. © The Author 2016. Medical Council on Alcohol and Oxford University Press. All rights reserved.

  5. 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 ...

  6. Dysphagia Assessed by the 10-Item Eating Assessment Tool Is Associated with Nutritional Status and Activities of Daily Living in Elderly Individuals Requiring Long-Term Care.

    Science.gov (United States)

    Wakabayashi, H; Matsushima, M

    2016-01-01

    The 10-item Eating Assessment Tool (EAT-10) is a self-administered questionnaire for dysphagia screening, with each item scored from 0 to 4. We assessed the associations among the EAT-10 score, nutritional status and activities of daily living (ADL) in elderly individuals requiring long-term care. Cross-sectional study. Geriatric health services facilities, acute hospitals, and the community. Elderly individuals ≥65 years of age with dysphagia or possible dysphagia (N=237). The EAT-10, the Mini Nutritional Assessment Short Form (MNA-SF) and the Barthel Index. There were 90 males and 147 females. Mean age was 82 ± 8 years. Eighty-nine were in geriatric health services facilities, 28 were in acute hospitals, and 120 were community-dwelling. The median Barthel Index score was 55 (interquartile range: 25, 80). The median EAT-10 score was 1 (interquartile range: 0, 9), and 101 respondents a score > 3, indicating the presence of dysphagia. The MNA-SF revealed that 81 were malnourished, 117 were at risk of malnutrition, and 39 had a normal nutritional status. The Barthel Index score and MNA-SF score were significantly lower in those with an EAT-10 score between 3 and 40, compared to those with an EAT-10 score between 0 and 2. The EAT-10 has an independent effect on the Barthel Index and the MNA-SF by adjusting for covariates such as age, gender, and setting in multiple regression analysis. Dysphagia assessed by the EAT-10 is associated with nutritional status and ADL in elderly individuals requiring long-term care.

  7. A Single Conjunction Risk Assessment Metric: the F-Value

    Science.gov (United States)

    Frigm, Ryan Clayton; Newman, Lauri K.

    2009-01-01

    The Conjunction Assessment Team at NASA Goddard Space Flight Center provides conjunction risk assessment for many NASA robotic missions. These risk assessments are based on several figures of merit, such as miss distance, probability of collision, and orbit determination solution quality. However, these individual metrics do not singly capture the overall risk associated with a conjunction, making it difficult for someone without this complete understanding to take action, such as an avoidance maneuver. The goal of this analysis is to introduce a single risk index metric that can easily convey the level of risk without all of the technical details. The proposed index is called the conjunction "F-value." This paper presents the concept of the F-value and the tuning of the metric for use in routine Conjunction Assessment operations.

  8. Effects of memantine on cognition in patients with moderate to severe Alzheimer's disease: post-hoc analyses of ADAS-cog and SIB total and single-item scores from six randomized, double-blind, placebo-controlled studies.

    Science.gov (United States)

    Mecocci, Patrizia; Bladström, Anna; Stender, Karina

    2009-05-01

    The post-hoc analyses reported here evaluate the specific effects of memantine treatment on ADAS-cog single-items or SIB subscales for patients with moderate to severe AD. Data from six multicentre, randomised, placebo-controlled, parallel-group, double-blind, 6-month studies were used as the basis for these post-hoc analyses. All patients with a Mini-Mental State Examination (MMSE) score of less than 20 were included. Analyses of patients with moderate AD (MMSE: 10-19), evaluated with the Alzheimer's disease Assessment Scale (ADAS-cog) and analyses of patients with moderate to severe AD (MMSE: 3-14), evaluated using the Severe Impairment Battery (SIB), were performed separately. The mean change from baseline showed a significant benefit of memantine treatment on both the ADAS-cog (p ADAS-cog single-item analyses showed significant benefits of memantine treatment, compared to placebo, for mean change from baseline for commands (p < 0.001), ideational praxis (p < 0.05), orientation (p < 0.01), comprehension (p < 0.05), and remembering test instructions (p < 0.05) for observed cases (OC). The SIB subscale analyses showed significant benefits of memantine, compared to placebo, for mean change from baseline for language (p < 0.05), memory (p < 0.05), orientation (p < 0.01), praxis (p < 0.001), and visuospatial ability (p < 0.01) for OC. Memantine shows significant benefits on overall cognitive abilities as well as on specific key cognitive domains for patients with moderate to severe AD. (c) 2009 John Wiley & Sons, Ltd.

  9. Varying the item format improved the range of measurement in patient-reported outcome measures assessing physical function.

    Science.gov (United States)

    Liegl, Gregor; Gandek, Barbara; Fischer, H Felix; Bjorner, Jakob B; Ware, John E; Rose, Matthias; Fries, James F; Nolte, Sandra

    2017-03-21

    Physical function (PF) is a core patient-reported outcome domain in clinical trials in rheumatic diseases. Frequently used PF measures have ceiling effects, leading to large sample size requirements and low sensitivity to change. In most of these instruments, the response category that indicates the highest PF level is the statement that one is able to perform a given physical activity without any limitations or difficulty. This study investigates whether using an item format with an extended response scale, allowing respondents to state that the performance of an activity is easy or very easy, increases the range of precise measurement of self-reported PF. Three five-item PF short forms were constructed from the Patient-Reported Outcomes Measurement Information System (PROMIS®) wave 1 data. All forms included the same physical activities but varied in item stem and response scale: format A ("Are you able to …"; "without any difficulty"/"unable to do"); format B ("Does your health now limit you …"; "not at all"/"cannot do"); format C ("How difficult is it for you to …"; "very easy"/"impossible"). Each short-form item was answered by 2217-2835 subjects. We evaluated unidimensionality and estimated a graded response model for the 15 short-form items and remaining 119 items of the PROMIS PF bank to compare item and test information for the short forms along the PF continuum. We then used simulated data for five groups with different PF levels to illustrate differences in scoring precision between the short forms using different item formats. Sufficient unidimensionality of all short-form items and the original PF item bank was supported. Compared to formats A and B, format C increased the range of reliable measurement by about 0.5 standard deviations on the positive side of the PF continuum of the sample, provided more item information, and was more useful in distinguishing known groups with above-average functioning. Using an item format with an extended

  10. Dimensionality and item-difficulty hierarchy of the lower-extremity Fugl-Meyer assessment in individuals with sub-acute and chronic stroke

    Science.gov (United States)

    Balasubramanian, Chitralakshmi K.; Li, Chih-Ying; Bowden, Mark G.; Duncan, Pamela W.; Kautz, Steven A.; Velozo, Craig A.

    2017-01-01

    Objective To investigate the dimensionality and item-difficulty hierarchy of the lower extremity section of the Fugl-Meyer assessment (FMA-LE). Design Secondary analyses of data pooled from four existing datasets: a Phase III randomized controlled trial investigating the effectiveness of body weight support and a treadmill for rehabilitation of walking post-stroke and three cross-sectional studies investigating the link between impaired motor performance post-stroke and walking. Setting University research centers and rehabilitation centers. Participants A pooled sample of 535 individuals with a stroke (age = 61.91 ± 12.42 years; male = 313). Interventions Not applicable. Main Outcome Measure(s) Confirmatory factor analyses (CFA) and Rasch residual Principal component analysis (PCA) investigated the dimensionality of the FMA-LE. The Rasch analysis rating scale model (RSM) investigated item-difficulty hierarchy of the FMA-LE. Results The CFA showed adequate fit of a three-factor model with 2/3 indices (CFA = 0.95; TLI = 0.94; RMSEA = 0.124) showing good model fit. Rasch PCA showed that removal of the reflex and coordination items explained 90.8% of variance in the data, suggesting that the abnormal synergy items contributed to the measurement of a unidimensional construct. However, RSM results revealed deviations in the item-difficulty hierarchy of the unidimensional abnormal synergy items from the originally proposed stepwise sequence of motor recovery. Conclusion(s) Our findings suggest that the FMA-LE might represent a multidimensional construct challenging the use of a total score of the FMA-LE to predict lower extremity motor recovery. Removal of the misfit items resulted in creation of a unidimensional scale comprised of the abnormal synergy items. However, this unidimensional scale deviates from the originally proposed hierarchical ordering. PMID:26740065

  11. Dimensionality and Item-Difficulty Hierarchy of the Lower Extremity Fugl-Meyer Assessment in Individuals With Subacute and Chronic Stroke.

    Science.gov (United States)

    Balasubramanian, Chitralakshmi K; Li, Chih-Ying; Bowden, Mark G; Duncan, Pamela W; Kautz, Steven A; Velozo, Craig A

    2016-04-01

    To investigate the dimensionality and item-difficulty hierarchy of the Fugl-Meyer Assessment of the lower extremity (FMA-LE). Secondary analyses of data pooled from 4 existing datasets: a phase III randomized controlled trial investigating the effectiveness of body weight support and a treadmill for rehabilitation of walking poststroke, and 3 cross-sectional studies investigating the link between impaired motor performance poststroke and walking. University research centers and rehabilitation centers. A pooled sample of individuals with a stroke (N=535, men=313; mean age ± SD, 61.91±12.42y). Not applicable. Confirmatory factor analyses (CFA) and Rasch residual principal component analysis (PCA) investigated the dimensionality of the FMA-LE. The Rasch analysis rating scale model investigated item-difficulty hierarchy of the FMA-LE. The CFA showed adequate fit of a 3-factor model, with 2 out of 3 indices (CFA=.95; Tucker-Lewis Index=.94; root mean square error of approximation=.124) showing good model fit. Rasch PCA showed that removal of the reflex and coordination items explained 90.8% of variance in the data, suggesting that the abnormal synergy items contributed to the measurement of a unidimensional construct. However, rating scale model results revealed deviations in the item-difficulty hierarchy of the unidimensional abnormal synergy items from the originally proposed stepwise sequence of motor recovery. Our findings suggest that the FMA-LE might represent a multidimensional construct, challenging the use of a total score of the FMA-LE to predict lower extremity motor recovery. Removal of the misfit items resulted in creation of a unidimensional scale composed of the abnormal synergy items. However, this unidimensional scale deviates from the originally proposed hierarchical ordering. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  12. Right ventricular function assessment in single LAD lesion patients ...

    African Journals Online (AJOL)

    Rania Gaber

    2015-10-09

    Oct 9, 2015 ... Abstract Background: Strain and strain rate imaging is currently the most popular echocardio- graphic technique that reveals subclinical myocardial damage, and data are not available on this imaging method with regard to assessing right ventricular involvement in single LAD lesion. Aim: To evaluate right ...

  13. Is a single item stress measure independently associated with subsequent severe injury: a prospective cohort study of 16,385 forest industry employees.

    Science.gov (United States)

    Salminen, Simo; Kouvonen, Anne; Koskinen, Aki; Joensuu, Matti; Väänänen, Ari

    2014-06-02

    A previous review showed that high stress increases the risk of occupational injury by three- to five-fold. However, most of the prior studies have relied on short follow-ups. In this prospective cohort study we examined the effect of stress on recorded hospitalised injuries in an 8-year follow-up. A total of 16,385 employees of a Finnish forest company responded to the questionnaire. Perceived stress was measured with a validated single-item measure, and analysed in relation recorded hospitalised injuries from 1986 to 2008. We used Cox proportional hazard regression models to examine the prospective associations between work stress, injuries and confounding factors. Highly stressed participants were approximately 40% more likely to be hospitalised due to injury over the follow-up period than participants with low stress. This association remained significant after adjustment for age, gender, marital status, occupational status, educational level, and physical work environment. High stress is associated with an increased risk of severe injury.

  14. Assessing the Equivalence of Paper, Mobile Phone, and Tablet Survey Responses at a Community Mental Health Center Using Equivalent Halves of a 'Gold-Standard' Depression Item Bank.

    Science.gov (United States)

    Brodey, Benjamin B; Gonzalez, Nicole L; Elkin, Kathryn Ann; Sasiela, W Jordan; Brodey, Inger S

    2017-09-06

    The computerized administration of self-report psychiatric diagnostic and outcomes assessments has risen in popularity. If results are similar enough across different administration modalities, then new administration technologies can be used interchangeably and the choice of technology can be based on other factors, such as convenience in the study design. An assessment based on item response theory (IRT), such as the Patient-Reported Outcomes Measurement Information System (PROMIS) depression item bank, offers new possibilities for assessing the effect of technology choice upon results. To create equivalent halves of the PROMIS depression item bank and to use these halves to compare survey responses and user satisfaction among administration modalities-paper, mobile phone, or tablet-with a community mental health care population. The 28 PROMIS depression items were divided into 2 halves based on content and simulations with an established PROMIS response data set. A total of 129 participants were recruited from an outpatient public sector mental health clinic based in Memphis. All participants took both nonoverlapping halves of the PROMIS IRT-based depression items (Part A and Part B): once using paper and pencil, and once using either a mobile phone or tablet. An 8-cell randomization was done on technology used, order of technologies used, and order of PROMIS Parts A and B. Both Parts A and B were administered as fixed-length assessments and both were scored using published PROMIS IRT parameters and algorithms. All 129 participants received either Part A or B via paper assessment. Participants were also administered the opposite assessment, 63 using a mobile phone and 66 using a tablet. There was no significant difference in item response scores for Part A versus B. All 3 of the technologies yielded essentially identical assessment results and equivalent satisfaction levels. Our findings show that the PROMIS depression assessment can be divided into 2 equivalent

  15. Improving the Reliability of Student Scores from Speeded Assessments: An Illustration of Conditional Item Response Theory Using a Computer-Administered Measure of Vocabulary

    Science.gov (United States)

    Petscher, Yaacov; Mitchell, Alison M.; Foorman, Barbara R.

    2015-01-01

    A growing body of literature suggests that response latency, the amount of time it takes an individual to respond to an item, may be an important factor to consider when using assessment data to estimate the ability of an individual. Considering that tests of passage and list fluency are being adapted to a computer administration format, it is…

  16. Psychometric Validation of the World Health Organization Disability Assessment Schedule 2.0-Twelve-Item Version in Persons with Spinal Cord Injuries

    Science.gov (United States)

    Smedema, Susan Miller; Ruiz, Derek; Mohr, Michael J.

    2017-01-01

    Purpose: To evaluate the factorial and concurrent validity and internal consistency reliability of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) 12-item version in persons with spinal cord injuries. Method: Two hundred forty-seven adults with spinal cord injuries completed an online survey consisting of the WHODAS…

  17. Differential Item Functioning Comparisons on a Performance-Based Alternate Assessment for Students with Severe Cognitive Impairments, Autism and Orthopedic Impairments

    Science.gov (United States)

    Laitusis, Cara Cahalan; Maneckshana, Behroz; Monfils, Lora; Ahlgrim-Delzell, Lynn

    2009-01-01

    The purpose of this study was to examine Differential Item Functioning (DIF) by disability groups on an on-demand performance assessment for students with severe cognitive impairments. Researchers examined the presence of DIF for two comparisons. One comparison involved students with severe cognitive impairments who served as the reference group…

  18. Electronic assessment of clinical reasoning in clerkships: A mixed-methods comparison of long-menu key-feature problems with context-rich single best answer questions

    NARCIS (Netherlands)

    Huwendiek, S.; Reichert, F.; Duncker, C.; Leng, B.A. De; Vleuten, C.P.M. van der; Muijtjens, A.M.; Bosse, H.M.; Haag, M.; Hoffmann, G.F.; Tonshoff, B.; Dolmans, D.

    2017-01-01

    BACKGROUND: It remains unclear which item format would best suit the assessment of clinical reasoning: context-rich single best answer questions (crSBAs) or key-feature problems (KFPs). This study compared KFPs and crSBAs with respect to students' acceptance, their educational impact, and

  19. Routine use of an abbreviated 4-item scale to assess dependence in essential activities of daily living amongst elderly hemodialysis patients: a validation study.

    Science.gov (United States)

    Farrokhi, Farhat; Jassal, Sarbjit V

    2013-02-01

    Poor functional status is associated with reduced survival and poor outcomes in older dialysis patients. The Geriatric Nephrology Advisory Group recommends routine evaluation of functional status on all older patients; however, assessments can be time consuming and burdensome to clinical care providers. The objective of this study was to validate an abbreviated 4-item self-report screening tool for use in elderly hemodialysis patients. The functional dependence of community-dwelling hemodialysis patients, aged ≥65 years, was measured by trained evaluators. The accuracy of a 4-item self-report activities of daily living (ADL) score was compared against formal evaluation by the Barthel Index and the outcomes using agreement statistics and Cox regression analysis. The cohort included 167 patients with a mean age of 74.8 ± 5.9 years (57 % males). The 4-item scale correctly identified 83 % of the patients dependent in ≥1 ADL. Those incorrectly identified as independent on the abbreviated scale were uniformly unable to climb stairs without assistance. The sensitivity and specificity, and coefficient for agreement between the 4-item scale and the Barthel Index were 83.2, 100 and 0.78 %, respectively. The positive and negative predictive values of the 4-item scale were 100 and 76.9 %, respectively. Using the 4-item scale, the presence of severe disability was predictive of increased mortality (HR 12.5; 95 % CI 2.5-65.0; P = 0.03). The 4-item scale is a simple, valid screening test for disability which can be used in the elderly population on dialysis as a screening tool. Difficulties with stair climbing may be overlooked using this score.

  20. Chip based single cell analysis for nanotoxicity assessment.

    Science.gov (United States)

    Shah, Pratikkumar; Kaushik, Ajeet; Zhu, Xuena; Zhang, Chengxiao; Li, Chen-Zhong

    2014-05-07

    Nanomaterials, because of their tunable properties and performances, have been utilized extensively in everyday life related consumable products and technology. On exposure, beyond the physiological range, nanomaterials cause health risks via affecting the function of organisms, genomic systems, and even the central nervous system. Thus, new analytical approaches for nanotoxicity assessment to verify the feasibility of nanomaterials for future use are in demand. The conventional analytical techniques, such as spectrophotometric assay-based techniques, usually require a lengthy and time-consuming process and often produce false positives, and often cannot be implemented at a single cell level measurement for studying cell behavior without interference from its surrounding environment. Hence, there is a demand for a precise, accurate, sensitive assessment for toxicity using single cells. Recently, due to the advantages of automation of fluids and minimization of human errors, the integration of a cell-on-a-chip (CoC) with a microfluidic system is in practice for nanotoxicity assessments. This review explains nanotoxicity and its assessment approaches with advantages/limitations and new approaches to overcome the confines of traditional techniques. Recent advances in nanotoxicity assessment using a CoC integrated with a microfluidic system are also discussed in this review, which may be of use for nanotoxicity assessment and diagnostics.

  1. Using existing questionnaires in latent class analysis: should we use summary scores or single items as input? A methodological study using a cohort of patients with low back pain

    Directory of Open Access Journals (Sweden)

    Nielsen AM

    2016-04-01

    Full Text Available Anne Molgaard Nielsen,1 Werner Vach,2 Peter Kent,1,3 Lise Hestbaek,1,4 Alice Kongsted1,4 1Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark; 2Center for Medical Biometry and Medical Informatics, Medical Center, University of Freiburg, Freiburg, Germany; 3School of Physiotherapy and Exercise Science, Curtin University, Perth, Australia; 4Nordic Institute of Chiropractic and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark Background: Latent class analysis (LCA is increasingly being used in health research, but optimal approaches to handling complex clinical data are unclear. One issue is that commonly used questionnaires are multidimensional, but expressed as summary scores. Using the example of low back pain (LBP, the aim of this study was to explore and descriptively compare the application of LCA when using questionnaire summary scores and when using single items to subgrouping of patients based on multidimensional data. Materials and methods: Baseline data from 928 LBP patients in an observational study were classified into four health domains (psychology, pain, activity, and participation using the World Health Organization’s International Classification of Functioning, Disability, and Health framework. LCA was performed within each health domain using the strategies of summary-score and single-item analyses. The resulting subgroups were descriptively compared using statistical measures and clinical interpretability. Results: For each health domain, the preferred model solution ranged from five to seven subgroups for the summary-score strategy and seven to eight subgroups for the single-item strategy. There was considerable overlap between the results of the two strategies, indicating that they were reflecting the same underlying data structure. However, in three of the four health domains, the single-item strategy resulted in a more nuanced description, in terms

  2. The Impact of Model Misspecification on Parameter Estimation and Item-Fit Assessment in Log-Linear Diagnostic Classification Models

    Science.gov (United States)

    Kunina-Habenicht, Olga; Rupp, Andre A.; Wilhelm, Oliver

    2012-01-01

    Using a complex simulation study we investigated parameter recovery, classification accuracy, and performance of two item-fit statistics for correct and misspecified diagnostic classification models within a log-linear modeling framework. The basic manipulated test design factors included the number of respondents (1,000 vs. 10,000), attributes (3…

  3. Assessment of chromium(VI) release from 848 jewellery items by use of a diphenylcarbazide spot test

    DEFF Research Database (Denmark)

    Bregnbak, David; Johansen, Jeanne D.; Hamann, Dathan

    2016-01-01

    We recently evaluated and validated a diphenylcarbazide(DPC)-based screening spot test that can detect the release of chromium(VI) ions (≥0.5 ppm) from various metallic items and leather goods (1). We then screened a selection of metal screws, leather shoes, and gloves, as well as 50 earrings...

  4. Differential Item Functioning Assessment in Cognitive Diagnostic Modeling: Application of the Wald Test to Investigate DIF in the DINA Model

    Science.gov (United States)

    Hou, Likun; de la Torre, Jimmy; Nandakumar, Ratna

    2014-01-01

    Analyzing examinees' responses using cognitive diagnostic models (CDMs) has the advantage of providing diagnostic information. To ensure the validity of the results from these models, differential item functioning (DIF) in CDMs needs to be investigated. In this article, the Wald test is proposed to examine DIF in the context of CDMs. This study…

  5. Creating a brief rating scale for the assessment of learning disabilities using reliability and true score estimates of the scale's items based on the Rasch model.

    Science.gov (United States)

    Sideridis, Georgios; Padeliadu, Susana

    2013-01-01

    The purpose of the present studies was to provide the means to create brief versions of instruments that can aid the diagnosis and classification of students with learning disabilities and comorbid disorders (e.g., attention-deficit/hyperactivity disorder). A sample of 1,108 students with and without a diagnosis of learning disabilities took part in study 1. Using information from modern theory methods (i.e., the Rasch model), a scale was created that included fewer than one third of the original battery items designed to assess reading skills. This best item synthesis was then evaluated for its predictive and criterion validity with a valid external reading battery (study 2). Using a sample of 232 students with and without learning disabilities, results indicated that the brief version of the scale was equally effective as the original scale in predicting reading achievement. Analysis of the content of the brief scale indicated that the best item synthesis involved items from cognition, motivation, strategy use, and advanced reading skills. It is suggested that multiple psychometric criteria be employed in evaluating the psychometric adequacy of scales used for the assessment and identification of learning disabilities and comorbid disorders.

  6. Recipient ineligibility after liver transplantation assessment: a single centre experience.

    Science.gov (United States)

    Arya, Aman; Hernandez-Alejandro, Roberto; Marotta, Paul; Uhanova, Julia; Chandok, Natasha

    2013-06-01

    Candidacy for liver transplantation is determined through standardized evaluation. There are limited data on the frequency and reasons for denial of transplantation after assessment; analysis may shed light on the short-term utility of the assessment. We sought to describe the frequency and reasons for ineligibility for liver transplantation among referred adults. We studied all prospectively followed recipient candidates at a single centre who were deemed unsuitable for liver transplantation after assessment. Inclusion criteria were age 18 years and older and completion of a standard liver transplantation evaluation over a 3-year period. Patients were excluded if they had a history of prior assessment or liver transplantation within the study period. Demographic and baseline clinical data and reasons for recipient ineligibility were recorded. In all, 337 patients underwent their first liver transplantation evaluation during the study period; 166 (49.3%) fulfilled inclusion criteria. The mean age was 55.4 years, and 106 (63.9%) were men. The 3 most common reasons for denial of listing were patient too well (n = 82, 49.4%), medical comorbidities and/or need for medical optimization (n = 43, 25.9%) and need for addiction rehabilitation (n = 28, 16.9%). Ineligibility for transplantation after assessment was common, occurring in nearly half of the cohort. Most denied candidates could be identified with more discriminate screening before the resource-intensive assessment; however, the assessment likely provides unforeseen positive impacts on patient care.

  7. A study on the establishment of safety assessment guidelines of commercial grade item dedication in digitalized safety systems

    International Nuclear Information System (INIS)

    Hwang, H. S.; Kim, B. R.; Oh, S. H.

    1999-01-01

    Because of obsolescing the components used in safety related systems of nuclear power plants, decreasing the number of suppliers qualified for the nuclear QA program and increasing maintenance costs of them, utilities have been considering to use commercial grade digital computers as an alternative for resolving such issues. However, commercial digital computers use the embedded pre-existing software, including operating system software, which are not developed by using nuclear grade QA program. Thus, it is necessary for utilities to establish processes for dedicating digital commercial grade items. A regulatory body also needs guidance to evaluate the digital commercial products properly. This paper surveyed the regulations and their regulatory guides, which establish the requirements for commercial grade items dedication, industry standards and guidances applicable to safety related systems. This paper provides some guidelines to be applied in evaluating the safety of digital upgrades and new digital plant protection systems in Korea

  8. Comparing the Effects of Different Smoothing Algorithms on the Assessment of Dimensionality of Ordered Categorical Items with Parallel Analysis.

    Science.gov (United States)

    Debelak, Rudolf; Tran, Ulrich S

    2016-01-01

    The analysis of polychoric correlations via principal component analysis and exploratory factor analysis are well-known approaches to determine the dimensionality of ordered categorical items. However, the application of these approaches has been considered as critical due to the possible indefiniteness of the polychoric correlation matrix. A possible solution to this problem is the application of smoothing algorithms. This study compared the effects of three smoothing algorithms, based on the Frobenius norm, the adaption of the eigenvalues and eigenvectors, and on minimum-trace factor analysis, on the accuracy of various variations of parallel analysis by the means of a simulation study. We simulated different datasets which varied with respect to the size of the respondent sample, the size of the item set, the underlying factor model, the skewness of the response distributions and the number of response categories in each item. We found that a parallel analysis and principal component analysis of smoothed polychoric and Pearson correlations led to the most accurate results in detecting the number of major factors in simulated datasets when compared to the other methods we investigated. Of the methods used for smoothing polychoric correlation matrices, we recommend the algorithm based on minimum trace factor analysis.

  9. Connecting single-stock assessment models through correlated survival

    DEFF Research Database (Denmark)

    Albertsen, Christoffer Moesgaard; Nielsen, Anders; Thygesen, Uffe Høgsbro

    2017-01-01

    the corresponding partial correlations. We consider six models where the partial correlation matrix between stocks follows a band structure ranging from independent assessments to complex correlation structures. Further, a simulation study illustrates the importance of handling correlated data sufficiently...... times. We propose a simple alternative. In three case studies each with two stocks, we improve the single-stock models, as measured by Akaike information criterion, by adding correlation in the cohort survival. To limit the number of parameters, the correlations are parameterized through...

  10. 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

  11. Item Response Data Analysis Using Stata Item Response Theory Package

    Science.gov (United States)

    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…

  12. An Arrangement of the Items Influencing Assessment of the Electrotechnical Technology Course / PROEJA, campuses Campos Centro and Itaperuna: The Learners’ View

    Directory of Open Access Journals (Sweden)

    Jorge Luíz Clemente Gomes

    2016-04-01

    Full Text Available This work aims to organize pre-defined items that affect the students’ answers when assessing the Electrotechnical Technology Course / PROEJA. The research was carried out from October / 2011 to December / 2012 with questionnaires applied with 1st to 6th period students. At campus Campos Centro, “Technical Visits” and “Internship” presented high levels of importance and low satisfaction, while “Personal Realization” and “Professional Achievement” presented high levels of relevance and satisfaction. At campus Itaperuna, “Job opportunities” and “Professional Achievement” presented high levels of relevance and satisfaction. Items “Faculty” and “New Technologies”, presented high importance but low satisfaction. The research aims at improving the quality of the course.

  13. An Integrated Approach to Bias in a Longitudinal Survey in the United Kingdom: Assessing Construct, Method, and Item Bias in the General Health Questionnaire (GHQ-12).

    Science.gov (United States)

    Benítez, Isabel; Adams, Byron G; He, Jia

    2017-11-01

    Construct, method, and item bias are three levels of measurement bias (i.e., internal bias) essential for valid group comparisons. While many studies often focus on only one level of bias, an integrated perspective on bias is still missing, especially in longitudinal designs. The aim of this study is to address bias in an integrated manner, using four waves of data in the U.K. Longitudinal Household Panel Survey. Responses to the General Health Questionnaire (GHQ-12) from natives and two generations of immigrants were used to analyze the three levels of bias. While the basic structure of the GHQ-12 was stable across groups and time, item and method bias decreased with repeated administrations. Results were confirmed with a sensitivity test. The integrated results allowed for a distinction between temporal sources of bias that became smaller over time and sources affecting valid comparisons persistently. We discuss the implications for mental health assessment.

  14. Why sample selection matters in exploratory factor analysis: implications for the 12-item World Health Organization Disability Assessment Schedule 2.0.

    Science.gov (United States)

    Gaskin, Cadeyrn J; Lambert, Sylvie D; Bowe, Steven J; Orellana, Liliana

    2017-03-11

    Sample selection can substantially affect the solutions generated using exploratory factor analysis. Validation studies of the 12-item World Health Organization (WHO) Disability Assessment Schedule 2.0 (WHODAS 2.0) have generally involved samples in which substantial proportions of people had no, or minimal, disability. With the WHODAS 2.0 oriented towards measuring disability across six life domains (cognition, mobility, self-care, getting along, life activities, and participation in society), performing factor analysis with samples of people with disability may be more appropriate. We determined the influence of the sampling strategy on (a) the number of factors extracted and (b) the factor structure of the WHODAS 2.0. Using data from adults aged 50+ from the six countries in Wave 1 of the WHO's longitudinal Study on global AGEing and adult health (SAGE), we repeatedly selected samples (n = 750) using two strategies: (1) simple random sampling that reproduced nationally representative distributions of WHODAS 2.0 summary scores for each country (i.e., positively skewed distributions with many zero scores indicating the absence of disability), and (2) stratified random sampling with weights designed to obtain approximately symmetric distributions of summary scores for each country (i.e. predominantly including people with varying degrees of disability). Samples with skewed distributions typically produced one-factor solutions, except for the two countries with the lowest percentages of zero scores, in which the majority of samples produced two factors. Samples with approximately symmetric distributions, generally produced two- or three-factor solutions. In the two-factor solutions, the getting along domain items loaded on one factor (commonly with a cognition domain item), with remaining items loading on a second factor. In the three-factor solutions, the getting along and self-care domain items loaded separately on two factors and three other domains

  15. Why sample selection matters in exploratory factor analysis: implications for the 12-item World Health Organization Disability Assessment Schedule 2.0

    Directory of Open Access Journals (Sweden)

    Cadeyrn J. Gaskin

    2017-03-01

    Full Text Available Abstract Background Sample selection can substantially affect the solutions generated using exploratory factor analysis. Validation studies of the 12-item World Health Organization (WHO Disability Assessment Schedule 2.0 (WHODAS 2.0 have generally involved samples in which substantial proportions of people had no, or minimal, disability. With the WHODAS 2.0 oriented towards measuring disability across six life domains (cognition, mobility, self-care, getting along, life activities, and participation in society, performing factor analysis with samples of people with disability may be more appropriate. We determined the influence of the sampling strategy on (a the number of factors extracted and (b the factor structure of the WHODAS 2.0. Methods Using data from adults aged 50+ from the six countries in Wave 1 of the WHO’s longitudinal Study on global AGEing and adult health (SAGE, we repeatedly selected samples (n = 750 using two strategies: (1 simple random sampling that reproduced nationally representative distributions of WHODAS 2.0 summary scores for each country (i.e., positively skewed distributions with many zero scores indicating the absence of disability, and (2 stratified random sampling with weights designed to obtain approximately symmetric distributions of summary scores for each country (i.e. predominantly including people with varying degrees of disability. Results Samples with skewed distributions typically produced one-factor solutions, except for the two countries with the lowest percentages of zero scores, in which the majority of samples produced two factors. Samples with approximately symmetric distributions, generally produced two- or three-factor solutions. In the two-factor solutions, the getting along domain items loaded on one factor (commonly with a cognition domain item, with remaining items loading on a second factor. In the three-factor solutions, the getting along and self-care domain items loaded separately

  16. Does the Assessment of Recovery Capital scale reflect a single or multiple domains?

    Directory of Open Access Journals (Sweden)

    Arndt S

    2017-07-01

    Full Text Available Stephan Arndt,1–3 Ethan Sahker,1,4 Suzy Hedden1 1Iowa Consortium for Substance Abuse Research and Evaluation, 2Department of Psychiatry, Carver College of Medicine, 3Department of Biostatistics, College of Public Health, 4Department of Psychological and Quantitative Foundations, Counseling Psychology Program College of Education, University of Iowa, Iowa City, IA, USA Objective: The goal of this study was to determine whether the 50-item Assessment of Recovery Capital scale represents a single general measure or whether multiple domains might be psychometrically useful for research or clinical applications. Methods: Data are from a cross-sectional de-identified existing program evaluation information data set with 1,138 clients entering substance use disorder treatment. Principal components and iterated factor analysis were used on the domain scores. Multiple group factor analysis provided a quasi-confirmatory factor analysis. Results: The solution accounted for 75.24% of the total variance, suggesting that 10 factors provide a reasonably good fit. However, Tucker’s congruence coefficients between the factor structure and defining weights (0.41–0.52 suggested a poor fit to the hypothesized 10-domain structure. Principal components of the 10-domain scores yielded one factor whose eigenvalue was greater than one (5.93, accounting for 75.8% of the common variance. A few domains had perceptible but small unique variance components suggesting that a few of the domains may warrant enrichment. Conclusion: Our findings suggest that there is one general factor, with a caveat. Using the 10 measures inflates the chance for Type I errors. Using one general measure avoids this issue, is simple to interpret, and could reduce the number of items. However, those seeking to maximally predict later recovery success may need to use the full instrument and all 10 domains. Keywords: social support, psychometrics, quality of life

  17. Neonatal Facial Coding System for assessing postoperative pain in infants: Item reduction is valid and feasible. [IF 1.9

    NARCIS (Netherlands)

    Peters, J.W.B.; Koot, H.M.; Grunau, R.; de Boer, J.B.; van Druenen, M.J.; Tibboel, D.; Duivenvoorden, H.J.

    2003-01-01

    Objective: The objectives of this study were to: (1) evaluate the validity of the Neonatal Facial Coding System (NFCS) for assessment of postoperative pain and (2) explore whether the number of NFCS facial actions could be reduced for assessing postoperative pain. Design: Prospective, observational

  18. Connecting Lines of Research on Task Model Variables, Automatic Item Generation, and Learning Progressions in Game-Based Assessment

    Science.gov (United States)

    Graf, Edith Aurora

    2014-01-01

    In "How Task Features Impact Evidence from Assessments Embedded in Simulations and Games," Almond, Kim, Velasquez, and Shute have prepared a thought-provoking piece contrasting the roles of task model variables in a traditional assessment of mathematics word problems to their roles in "Newton's Playground," a game designed…

  19. Development of traditional Chinese version of World Health Organization disability assessment schedule 2.0 36--item (WHODAS 2.0) in Taiwan: validity and reliability analyses.

    Science.gov (United States)

    Chiu, Tzu-Ying; Yen, Chia-Feng; Chou, Cheng-Hsiu; Lin, Jin-Ding; Hwang, Ai-Wen; Liao, Hua-Fang; Chi, Wen-Chou

    2014-11-01

    World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) provided a standardized method for measuring the health and disability and the traditional Chinese version has not been developed. To describe the process of developing the traditional Chinese version of the WHODAS 2.0 36-item version and to evaluate the concurrent validity and test-retest reliability of this instrument. The study was conducted in two phases. Phase I was the process of translation of WHODAS 2.0 36-item version. Phase II was a cross-sectional study. The participants were 307 adults who were tested the validity and reliability of draft traditional Chinese version. The reliability of Cronbach's α and ICC in the WHODAS 2.0 traditional Chinese version were 0.73-0.99 and 0.8-089, respectively. The content validity was good (r=0.7-0.76), and the concurrent validity was excellent in comparison with the WHOQOL-BREF (pdisability. There was a valid and reliable measurement scales for evaluating functioning and disability status. For disability eligibility system of Taiwan government to measure the disability, the traditional Chinese version of the WHODAS 2.0 provided valuable evidence to design the assessment instrument. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Addressing challenges in single species assessments via a simple state-space assessment model

    DEFF Research Database (Denmark)

    Nielsen, Anders

    Single-species and age-structured fish stock assessments still remains the main tool for managing fish stocks. A simple state-space assessment model is presented as an alternative to (semi) deterministic procedures and the full parametric statistical catch at age models. It offers a solution...... to some of the key challenges of these models. Compared to the deterministic procedures it solves a list of problems originating from falsely assuming that age classified catches are known without errors and allows quantification of uncertainties of estimated quantities of interest. Compared to full...

  1. Feasibility, reliability, and validity of the Japanese version of the 12-item World Health Organization Disability Assessment Schedule-2 in preoperative patients.

    Science.gov (United States)

    Ida, Mitsuru; Naito, Yusuke; Tanaka, Yuu; Matsunari, Yasunori; Inoue, Satoki; Kawaguchi, Masahiko

    2017-08-01

    The avoidance of postoperative functional disability is one of the most important concerns of patients facing surgery, but methods to evaluate disability have not been definitively established. The aim of our study was to evaluate the feasibility, reliability, and validity of the Japanese version of the 12-item World Health Organization Disability Assessment Schedule-2 (WHODAS 2.0-J) in preoperative patients. Individuals aged ≥55 years who were scheduled to undergo surgery in a tertiary-care hospital in Japan between April 2016 and September 2016 were eligible for enrolment in the study. All patients were assessed preoperatively using the WHODAS 2.0-J, the 8-Item Short Form (SF-8) questionnaire, and the Tokyo Metropolitan Institute of Gerontology Index (TMIG Index). The feasibility, reliability, and validity of WHODAS2.0-J were evaluated using response rate, Cronbach's alpha (a measure of reliability), and the correlation between the WHODAS 2.0-J and the SF-8 questionnaire and TMIG Index, respectively. A total of 934 patients were enrolled in the study during the study period, of whom 930 completed the WHODAS 2.0-J (response rate 99.5%) preoperatively. Reliability and validity were assessed in the 898 patients who completed all three assessment tools (WHODAS 2.0-J, SF-8 questionnaire, and TMIG Index) and for whom all demographic data were available. Cronbach's alpha was 0.92. The total score of the WHODAS 2.0-J showed a mild or moderate correlation with the SF-8 questionnaire and TMIG Index (r = -0.63 to -0.34). The WHODAS 2.0-J is a feasible, reliable, and valid instrument for evaluating preoperative functional disability in surgical patients.

  2. Assessing First- and Second-Order Equity for the Common-Item Nonequivalent Groups Design Using Multidimensional IRT

    Science.gov (United States)

    Andrews, Benjamin James

    2011-01-01

    The equity properties can be used to assess the quality of an equating. The degree to which expected scores conditional on ability are similar between test forms is referred to as first-order equity. Second-order equity is the degree to which conditional standard errors of measurement are similar between test forms after equating. The purpose of…

  3. Exploring Different Types of Assessment Items to Measure Linguistically Diverse Students' Understanding of Energy and Matter in Chemistry

    Science.gov (United States)

    Ryoo, Kihyun; Toutkoushian, Emily; Bedell, Kristin

    2018-01-01

    Energy and matter are fundamental, yet challenging concepts in middle school chemistry due to their abstract, unobservable nature. Although it is important for science teachers to elicit a range of students' ideas to design and revise their instruction, capturing such varied ideas using traditional assessments consisting of multiple-choice items…

  4. Oral/dental items in the resident assessment instrument - minimum Data Set 2.0 lack validity: results of a retrospective, longitudinal validation study.

    Science.gov (United States)

    Hoben, Matthias; Poss, Jeffrey W; Norton, Peter G; Estabrooks, Carole A

    2016-01-01

    Oral health in nursing home residents is poor. Robust, mandated assessment tools such as the Resident Assessment Instrument - Minimum Data Set (RAI-MDS) 2.0 are key to monitoring and improving quality of oral health care in nursing homes. However, psychometric properties of RAI-MDS 2.0 oral/dental items have been challenged and criterion validity of these items has never been assessed. We used 73,829 RAI-MDS 2.0 records (13,118 residents), collected in a stratified random sample of 30 urban nursing homes in Western Canada (2007-2012). We derived a subsample of all residents ( n  = 2,711) with an admission and two or more subsequent annual assessments. Using Generalized Estimating Equations, adjusted for known covariates of nursing home residents' oral health, we assessed the association of oral/dental problems with time, dentate status, dementia, debris, and daily cleaning. Prevalence of oral/dental problems fluctuated (4.8 %-5.6 %) with no significant differences across time. This range of prevalence is substantially smaller than the ones reported by studies using clinical assessments by dental professionals. Denture wearers were less likely than dentate residents to have oral/dental problems (adjusted odds ratio [OR] = 0.458, 95 % confidence interval [CI]: 0.308, 0.680). Residents lacking teeth and not wearing dentures had higher odds than dentate residents of oral/dental problems (adjusted OR = 2.718, 95 % CI: 1.845, 4.003). Oral/dental problems were more prevalent in persons with debris (OR = 2.187, 95 % CI: 1.565, 3.057). Of the other variables assessed, only age at assessment was significantly associated with oral/dental problems. Robust, reliable RAI-MDS 2.0 oral health indicators are vital to monitoring and improving oral health related quality and safety in nursing homes. However, severe underdetection of oral/dental problems and lack of association of well-known oral health predictors with oral/dental problems suggest validity

  5. Oral/dental items in the resident assessment instrument – minimum Data Set 2.0 lack validity: results of a retrospective, longitudinal validation study

    Directory of Open Access Journals (Sweden)

    Matthias Hoben

    2016-10-01

    Full Text Available Abstract Background Oral health in nursing home residents is poor. Robust, mandated assessment tools such as the Resident Assessment Instrument – Minimum Data Set (RAI-MDS 2.0 are key to monitoring and improving quality of oral health care in nursing homes. However, psychometric properties of RAI-MDS 2.0 oral/dental items have been challenged and criterion validity of these items has never been assessed. Methods We used 73,829 RAI-MDS 2.0 records (13,118 residents, collected in a stratified random sample of 30 urban nursing homes in Western Canada (2007–2012. We derived a subsample of all residents (n = 2,711 with an admission and two or more subsequent annual assessments. Using Generalized Estimating Equations, adjusted for known covariates of nursing home residents’ oral health, we assessed the association of oral/dental problems with time, dentate status, dementia, debris, and daily cleaning. Results Prevalence of oral/dental problems fluctuated (4.8 %–5.6 % with no significant differences across time. This range of prevalence is substantially smaller than the ones reported by studies using clinical assessments by dental professionals. Denture wearers were less likely than dentate residents to have oral/dental problems (adjusted odds ratio [OR] = 0.458, 95 % confidence interval [CI]: 0.308, 0.680. Residents lacking teeth and not wearing dentures had higher odds than dentate residents of oral/dental problems (adjusted OR = 2.718, 95 % CI: 1.845, 4.003. Oral/dental problems were more prevalent in persons with debris (OR = 2.187, 95 % CI: 1.565, 3.057. Of the other variables assessed, only age at assessment was significantly associated with oral/dental problems. Conclusions Robust, reliable RAI-MDS 2.0 oral health indicators are vital to monitoring and improving oral health related quality and safety in nursing homes. However, severe underdetection of oral/dental problems and lack of association of well-known oral

  6. My mind is as clear as it used to be: A pilot study illustrating the difficulties of employing a single-item subjective screen to detect cognitive impairment in outpatients with cancer.

    Science.gov (United States)

    Kibiger, Gail; Kirsh, Kenneth L; Wall, Jacqueline R; Passik, Steven D

    2003-08-01

    Oncology patients often complain that their "mind does not seem to be clear." This subjective perception, sometimes referred to as "chemo brain," may be due to situational stressors, psychological disorders, organic factors, or effects of neurotoxic medications. Cognitive decline cannot only diminish quality of life, but can also interfere with a patient's ability to make decisions regarding complex treatment issues. The current study investigated the utility of using item 11 of the Zung Self-Rating Depression Screen (ZSDS) as a cognitive screen. A sample of 61 ambulatory cancer patients completed this study. Participants were recruited from four sites of Community Cancer Care, Inc., in Indiana. A battery of cognitive instruments and psychosocial inventories was administered in a standardized order. The sample had a mean age of 58.6 years and comprised 57.4% (n=35) women and 42.6% (n=26) men. Item 11 of the ZSDS was not significantly correlated to the cognitive measures. Correlates of the perception of cognitive impairment were the Dementia Rating Scale (DRS) Attention Scale (r=-0.26, PStroop test (F=19.8, Pspecificity indicated that the single-item screen used in this study is not an accurate means for identifying oncology patients with actual cognitive impairment. We conclude that while the perception of cognitive impairment is common in cancer patients, there may be problems in interpreting the nature of these complaints, particularly in separating them from depressive preoccupation.

  7. 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.

  8. Correlation between the pain numeric rating scale and the 12-item WHO Disability Assessment Schedule 2.0 in patients with musculoskeletal pain.

    Science.gov (United States)

    Saltychev, Mikhail; Bärlund, Esa; Laimi, Katri

    2018-03-01

    The aim of this study was to assess the correlation between pain severity measured on a numeric rating scale and restrictions of functioning measured with the WHO Disability Assessment Schedule (WHODAS 2.0). This was a cross-sectional study of 1207 patients with musculoskeletal pain conditions. Correlation was assessed using Spearman's and Pearson tests. Although all the Spearman's rank correlations between WHODAS 2.0 items and pain severity were statistically significant, they were mostly weak, with only a few moderate associations for 'S2 household responsibilities', 'S8 washing', 'S9 dressing', and 'S12 day-to-day work'. The correlation between the WHODAS 2.0 total score and pain severity was also moderate: 0.41 [95% confidence interval (CI): 0.36-0.45] for average pain and 0.42 (95% CI: 0.37-0.46) for worst pain. The correlation between the WHODAS 2.0 total score and pain level was also assessed using Pearson's product-moment correlation, yielding figures that were similar to Spearman's correlation: 0.42 (PWHODAS 2.0 was weak to moderate, with slightly stronger associations in physical domains of functioning.

  9. An NCME Instructional Module on Polytomous Item Response Theory Models

    Science.gov (United States)

    Penfield, Randall David

    2014-01-01

    A polytomous item is one for which the responses are scored according to three or more categories. Given the increasing use of polytomous items in assessment practices, item response theory (IRT) models specialized for polytomous items are becoming increasingly common. The purpose of this ITEMS module is to provide an accessible overview of…

  10. The Ability of the 10-Item Eating Assessment Tool (EAT-10) to Predict Aspiration Risk in Persons With Dysphagia.

    Science.gov (United States)

    Cheney, Diane M; Siddiqui, M Tausif; Litts, Juliana K; Kuhn, Maggie A; Belafsky, Peter C

    2015-05-01

    Dysphagia is common and costly. The ability of patient symptoms to predict objective swallowing dysfunction is uncertain. This study aimed to evaluate the ability of the Eating Assessment Tool (EAT-10) to screen for aspiration risk in patients with dysphagia. Data from individuals with dysphagia undergoing a videofluoroscopic swallow study between January 2012 and July 2013 were abstracted from a clinical database. Data included the EAT-10, Penetration Aspiration Scale (PAS), total pharyngeal transit (TPT) time, and underlying diagnoses. Bivariate linear correlation analysis, sensitivity, specificity, and predictive values were calculated. The mean age of the entire cohort (N=360) was 64.40 (±14.75) years. Forty-six percent were female. The mean EAT-10 was 16.08 (±10.25) for nonaspirators and 23.16 (±10.88) for aspirators (PEAT-10 score and the PAS (r=0.273, PEAT-10>15 in predicting aspiration were 71% and 53%, respectively. Subjective dysphagia symptoms as documented with the EAT-10 can predict aspiration risk. A linear correlation exists between the EAT-10 and aspiration events (PAS) and aspiration risk (TPT time). Persons with an EAT-10>15 are 2.2 times more likely to aspirate (95% confidence interval, 1.3907-3.6245). The sensitivity of an EAT-10>15 is 71%. © The Author(s) 2014.

  11. Surveying Assessment in Experiential Learning: A Single Campus Study

    Science.gov (United States)

    Yates, Thomas; Wilson, Jay; Purton, Kendra

    2015-01-01

    The purpose of this study was to determine the methods of experiential assessment in use at a Canadian university and the extent to which they are used. Exploring experiential assessment will allow identification of commonly used methods and facilitate the development of best practices of assessment in the context of experiential learning (EL) at…

  12. Rats Remember Items in Context Using Episodic Memory.

    Science.gov (United States)

    Panoz-Brown, Danielle; Corbin, Hannah E; Dalecki, Stefan J; Gentry, Meredith; Brotheridge, Sydney; Sluka, Christina M; Wu, Jie-En; Crystal, Jonathon D

    2016-10-24

    Vivid episodic memories in people have been characterized as the replay of unique events in sequential order [1-3]. Animal models of episodic memory have successfully documented episodic memory of a single event (e.g., [4-8]). However, a fundamental feature of episodic memory in people is that it involves multiple events, and notably, episodic memory impairments in human diseases are not limited to a single event. Critically, it is not known whether animals remember many unique events using episodic memory. Here, we show that rats remember many unique events and the contexts in which the events occurred using episodic memory. We used an olfactory memory assessment in which new (but not old) odors were rewarded using 32 items. Rats were presented with 16 odors in one context and the same odors in a second context. To attain high accuracy, the rats needed to remember item in context because each odor was rewarded as a new item in each context. The demands on item-in-context memory were varied by assessing memory with 2, 3, 5, or 15 unpredictable transitions between contexts, and item-in-context memory survived a 45 min retention interval challenge. When the memory of item in context was put in conflict with non-episodic familiarity cues, rats relied on item in context using episodic memory. Our findings suggest that rats remember multiple unique events and the contexts in which these events occurred using episodic memory and support the view that rats may be used to model fundamental aspects of human cognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. On the validity of measuring change over time in routine clinical assessment: a close examination of item-level response shifts in psychosomatic inpatients.

    Science.gov (United States)

    Nolte, S; Mierke, A; Fischer, H F; Rose, M

    2016-06-01

    Significant life events such as severe health status changes or intensive medical treatment often trigger response shifts in individuals that may hamper the comparison of measurements over time. Drawing from the Oort model, this study aims at detecting response shift at the item level in psychosomatic inpatients and evaluating its impact on the validity of comparing repeated measurements. Complete pretest and posttest data were available from 1188 patients who had filled out the ICD-10 Symptom Rating (ISR) scale at admission and discharge, on average 24 days after intake. Reconceptualization, reprioritization, and recalibration response shifts were explored applying tests of measurement invariance. In the item-level approach, all model parameters were constrained to be equal between pretest and posttest. If non-invariance was detected, these were linked to the different types of response shift. When constraining across-occasion model parameters, model fit worsened as indicated by a significant Satorra-Bentler Chi-square difference test suggesting potential presence of response shifts. A close examination revealed presence of two types of response shift, i.e., (non)uniform recalibration and both higher- and lower-level reconceptualization response shifts leading to four model adjustments. Our analyses suggest that psychosomatic inpatients experienced some response shifts during their hospital stay. According to the hierarchy of measurement invariance, however, only one of the detected non-invariances is critical for unbiased mean comparisons over time, which did not have a substantial impact on estimating change. Hence, the use of the ISR can be recommended for outcomes assessment in clinical routine, as change score estimates do not seem hampered by response shift effects.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Development of the Japan Science and Technology Agency Index of Competence to Assess Functional Capacity in Older Adults: Conceptual Definitions and Preliminary Items.

    Science.gov (United States)

    Iwasa, Hajime; Masui, Yukie; Inagaki, Hiroki; Yoshida, Yuko; Shimada, Hiroyuki; Otsuka, Rika; Kikuchi, Kazunori; Nonaka, Kumiko; Yoshida, Hiroto; Yoshida, Hideyo; Suzuki, Takao

    2015-01-01

    Improvement in the health of older people and changes in their lifestyles necessitate a scale that can better measure their competence at a higher level. This study describes the development process of the Japan Science and Technology Agency Index of Competence (JST-IC) by (a) refining conceptual definitions and developing preliminary items and (b) examining the basic properties of the items. Participants were 1,253 septuagenarians (539 men and 714 women) living in communities, who were asked to judge whether they were independent via 88 items. To examine the basic properties of the preliminary items, five different analyses were conducted. Thirty-four items were considered as inappropriate (6 overlapped between the analyses): (a) 9 due to very high or low ratios of responders who answered "yes," (b) 4 due to gender or regional differences, (c) 5 due to their weak association with health status, (d) 9 due to low communalities in factor analysis, and (e) 13 due to redundancy of meaning with other items. Conceptual definitions and preliminary items were developed, and the basic properties of the items were examined to create the JST-IC. The next step would be to screen the remaining 54 items to create the final version of the scale.

  16. Comparative energy storage assessment item

    Science.gov (United States)

    Giudici, B.

    1984-11-01

    This analysis, a Space Station application study, rediscovered Integrated Power and Attitude Control (IPAC) and found the approach to have lower initial and resupply weight and lower initial and resupply cost than either battery/CMG or regenerative fuel cell/CMG systems. Preliminary trade studies were performed comparing (IPAC) with equivalent independent electrochemical power and control moment gyro (CMG) control approaches. Technologies considered to have adequate status for an initial Space Station were: (1) nickel cadmium batteries (NiCd batteries), (2) regenerative fuel cells (RFC), (3) Skylab class CMG's, and (4) state of the art IPAC using metal wheels and ball bearing suspension (SOA-IPAC). An advanced IPAC (ADV-IPAC) employing composite rotor material and magnetic suspension was included in the comparisons to illustrate a possible range of performance and cost of inertial systems. The candidates were compared on the basis of initial weight and cost and on the basis of resupply weight and cost for a 15 year mission. Thus, SOA-IPAC would appear to be an attractive approach for the initial Space Station and possible technology improvements would further the appeal for the initial and/or growth Space Station.

  17. Self-reported cognitive distortions in the psychosis continuum: A Polish 18-item version of the Davos Assessment of Cognitive Biases Scale (DACOBS-18).

    Science.gov (United States)

    Gawęda, Łukasz; Prochwicz, Katarzyna; Krężołek, Martyna; Kłosowska, Joanna; Staszkiewicz, Maciej; Moritz, Steffen

    2018-02-01

    The aim of this study was to provide a short version of the Davos Assessment of Cognitive Biases Scale (DACOBS), which is a self-report tool to assess cognitive distortions related to psychosis. A principal component analysis (PCA) was conducted on a large non-clinical sample (n=1207) and cross-validated with a confirmatory factor analysis on an independent non-clinical sample (n=653). Discriminative validity was performed by contrasting the high risk for psychosis non-clinical sample (n=63), low risk for psychosis non-clinical sample (n=152), patients with schizophrenia (n=105), and patients with depression (n=56). Correlations between symptoms, cognitive functions, source monitoring deficits, and jumping to conclusions were performed among a subgroup of patients with schizophrenia. An 18-item scale (DACOBS-18) with a four-factor solution was established. Internal consistency (α=0.84) and test-retest reliability (r=0.84, pcognitive measures is needed. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Surveying Assessment in Experiential Learning: A Single Campus Study

    Directory of Open Access Journals (Sweden)

    Thomas Yates

    2015-12-01

    Full Text Available The purpose of this study was to determine the methods of experiential assessment in use at a Canadian university and the extent to which they are used. Exploring experiential assessment will allow identification of commonly used methods and facilitate the development of best practices of assessment in the context of experiential learning (EL at an institutional level. The origins of EL are found in the work of Dewey (1938, later modified by Kolb and Fry (1975. Experiential methods include: experiential education, service learning problem-based learning and others such as action learning, enquiry-based learning, and case studies. Faculty currently involved in EL at the participating university were invited to complete an online survey about their teaching and assessment methods. This paper will share the results and analysis of the EL inventory survey.

  19. Dynamics Assessment of Advanced Single-Phase PLL Structures

    DEFF Research Database (Denmark)

    Golestan, Saeed; Monfarad, Mohammad; Freijedo, Francisco D.

    2013-01-01

    , and desired performance under frequency-varying and harmonically distorted grid conditions. Despite the wide acceptance and use of these two advanced PLLs, no comprehensive design guidelines to fine-tune their parameters have been reported yet. Through a detailed mathematical analysis it is shown......Recently, several advanced phase locked loop (PLL) techniques have been proposed for single-phase applications. Among these, the Park-PLL, and the second order generalized integrator (SOGI) based PLL are very attractive, owing to their simple digital implementation, low computational burden...

  20. Use of UV-C radiation to disinfect non-critical patient care items: a laboratory assessment of the Nanoclave Cabinet

    Science.gov (United States)

    2012-01-01

    Background The near-patient environment is often heavily contaminated, yet the decontamination of near-patient surfaces and equipment is often poor. The Nanoclave Cabinet produces large amounts of ultraviolet-C (UV-C) radiation (53 W/m2) and is designed to rapidly disinfect individual items of clinical equipment. Controlled laboratory studies were conducted to assess its ability to eradicate a range of potential pathogens including Clostridium difficile spores and Adenovirus from different types of surface. Methods Each test surface was inoculated with known levels of vegetative bacteria (106 cfu/cm2), C. difficile spores (102-106 cfu/cm2) or Adenovirus (109 viral genomes), placed in the Nanoclave Cabinet and exposed for up to 6 minutes to the UV-C light source. Survival of bacterial contaminants was determined via conventional cultivation techniques. Degradation of viral DNA was determined via PCR. Results were compared to the number of colonies or level of DNA recovered from non-exposed control surfaces. Experiments were repeated to incorporate organic soils and to compare the efficacy of the Nanoclave Cabinet to that of antimicrobial wipes. Results After exposing 8 common non-critical patient care items to two 30-second UV-C irradiation cycles, bacterial numbers on 40 of 51 target sites were consistently reduced to below detectable levels (≥ 4.7 log10 reduction). Bacterial load was reduced but still persisted on other sites. Objects that proved difficult to disinfect using the Nanoclave Cabinet (e.g. blood pressure cuff) were also difficult to disinfect using antimicrobial wipes. The efficacy of the Nanoclave Cabinet was not affected by the presence of organic soils. Clostridium difficile spores were more resistant to UV-C irradiation than vegetative bacteria. However, two 60-second irradiation cycles were sufficient to reduce the number of surface-associated spores from 103 cfu/cm2 to below detectable levels. A 3 log10 reduction in detectable Adenovirus DNA

  1. Use of UV-C radiation to disinfect non-critical patient care items: a laboratory assessment of the Nanoclave Cabinet

    Directory of Open Access Journals (Sweden)

    Moore Ginny

    2012-08-01

    Full Text Available Abstract Background The near-patient environment is often heavily contaminated, yet the decontamination of near-patient surfaces and equipment is often poor. The Nanoclave Cabinet produces large amounts of ultraviolet-C (UV-C radiation (53 W/m2 and is designed to rapidly disinfect individual items of clinical equipment. Controlled laboratory studies were conducted to assess its ability to eradicate a range of potential pathogens including Clostridium difficile spores and Adenovirus from different types of surface. Methods Each test surface was inoculated with known levels of vegetative bacteria (106 cfu/cm2, C. difficile spores (102-106 cfu/cm2 or Adenovirus (109 viral genomes, placed in the Nanoclave Cabinet and exposed for up to 6 minutes to the UV-C light source. Survival of bacterial contaminants was determined via conventional cultivation techniques. Degradation of viral DNA was determined via PCR. Results were compared to the number of colonies or level of DNA recovered from non-exposed control surfaces. Experiments were repeated to incorporate organic soils and to compare the efficacy of the Nanoclave Cabinet to that of antimicrobial wipes. Results After exposing 8 common non-critical patient care items to two 30-second UV-C irradiation cycles, bacterial numbers on 40 of 51 target sites were consistently reduced to below detectable levels (≥ 4.7 log10 reduction. Bacterial load was reduced but still persisted on other sites. Objects that proved difficult to disinfect using the Nanoclave Cabinet (e.g. blood pressure cuff were also difficult to disinfect using antimicrobial wipes. The efficacy of the Nanoclave Cabinet was not affected by the presence of organic soils. Clostridium difficile spores were more resistant to UV-C irradiation than vegetative bacteria. However, two 60-second irradiation cycles were sufficient to reduce the number of surface-associated spores from 103 cfu/cm2 to below detectable levels. A 3 log10 reduction in

  2. A single-item self-rated health measure correlates with objective health status in the elderly: a survey in suburban Beijing

    Directory of Open Access Journals (Sweden)

    Qinqin eMeng

    2014-04-01

    Full Text Available IntroductionThe measurement of health status of the elderly remains one important topic. Self-rated health status (SRH is considered to be a simple indicator to measure the health status of the old population. But some researchers still take a skeptical view about its reliability. This study aims to investigate the association between self-rated health indicator and health status of the elderly and discuss its subsequent public health implications.MethodsIn a total 1096 people who were 60 years of age or older from 1784 households from a suburban area of Beijing were interviewed using multistage stratified cluster sampling. SRH was measured by a single question please choose one point in this 0-100 scale which can best represent your health today?. The disease status and physical functional status were also obtained. A multiple linear regression was conducted to test the associate between SRH and individual’s disease/functional status.ResultsThe average of SRH scores of the elderly was 72.49±15.64 (on a 1 to 100 scale. The SRH scores declined not only with the severity of self-reported mental/disease status, but also with the decrease of physical functional status. Multiple linear regression showed that after adjustment for other variables, two-week sickness, chronic diseases, hospitalization, and ability of self-care (washing and dressing were able to explain 35% of the variation in SRH among the elderly. Among them, disease status and self-care ability were the most powerful predictor of SRH. After adjusting other variables, physical functional status could explain only 5% of the variation in SRH.ConclusionSRH reflects the disease/functional health status of the elderly. It is an easy-to-implement variable and it can reduce both recall bias and investigator bias, thus being widely used in health surveys. It is a cost-effective means of measuring the health status. However, the comparability of SRH in different populations should be studied

  3. 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…

  4. Learning environment assessments of a single curriculum being taught at two medical schools 10,000 miles apart.

    Science.gov (United States)

    Tackett, Sean; Shochet, Robert; Shilkofski, Nicole A; Colbert-Getz, Jorie; Rampal, Krishna; Abu Bakar, Hamidah; Wright, Scott

    2015-06-17

    Perdana University Graduate School of Medicine (PUGSOM), the first graduate-entry medical school in Malaysia, was established in 2011 in collaboration with Johns Hopkins University School of Medicine (JHUSOM), an American medical school. This study compared learning environments (LE) at these two schools, which shared the same overarching curriculum, along with a comparator Malaysian medical school, Cyberjaya University College of Medical Sciences (CUCMS). As a secondary aim, we compared 2 LE assessment tools - the widely-used Dundee Ready Educational Environment Measure (DREEM) and the newer Johns Hopkins Learning Environment Scale (JHLES). Students responded anonymously at the end of their first year of medical school to surveys which included DREEM, JHLES, single-item global LE assessment variables, and demographics questions. Respondents included 24/24 (100 %) students at PUGSOM, 100/120 (83 %) at JHUSOM, and 79/83 (95 %) at CUCMS. PUGSOM had the highest overall LE ratings (p safety" domains. JHLES detected significant differences across schools in 5/7 domains and had stronger correlations than DREEM to each global LE assessment variable. The inaugural class of medical students at PUGSOM rated their LE exceptionally highly, providing evidence that transporting a medical school curriculum may be successful. The JHLES showed promise as a LE assessment tool for use in international settings.

  5. Assessing the scientific relevance of a single publication over time

    Directory of Open Access Journals (Sweden)

    Philipp A. Bloching

    2013-09-01

    Full Text Available Quantitatively assessing the scientific relevance of a research paper is challenging for two reasons. Firstly, scientific relevance may change over time, and secondly, it is unclear how to evaluate a recently published paper. The temporally averaged paper-specific impact factor is defined as the yearly average of citations to the paper until now including bonus citations equal to the journal impact factor in the publication year. This new measure subsequently allows relevance rankings and annual updates of all (i.e. both recent and older scientific papers of a department, or even a whole scientific field, on a more objective basis. It can also be used to assess both the average and overall time-dependent scientific relevance of researchers in a specific department or scientific field.

  6. Validity of the 12-item World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) in individuals with Huntington disease (HD).

    Science.gov (United States)

    Carlozzi, Noelle E; Kratz, Anna L; Downing, Nancy R; Goodnight, Siera; Miner, Jennifer A; Migliore, Nicholas; Paulsen, Jane S

    2015-08-01

    The reliability and construct validity of the 12-item World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) were examined in individuals with Huntington disease (HD). We examined factor structure (confirmatory factor analysis), internal consistency reliability (Cronbach's alpha), floor and ceiling effects, convergent validity (Pearson correlations), and known-groups validity (multivariate analysis). Results of a confirmatory factor analysis replicated the six-factor latent model that reflects the six separate scales within the WHODAS 2.0 (understanding and communicating; getting around; self-care; getting along with others; life activities; participation). Cronbach's alpha for the scale was 0.94, suggesting good internal consistency reliability. The WHODAS demonstrated a ceiling effect for 19.5 % of participants; there were no floor effects. There was evidence for convergent validity; the WHODAS demonstrated moderate significant correlations with other general measures of health-related quality of life (HRQOL; i.e., RAND-12, EQ5D). Multivariate analyses indicated that late-stage HD participants indicated poorer HRQOL than both early-stage HD and prodromal HD participants for all HRQOL measures. Findings provide support for both the reliability and validity of the WHODAS 2.0 in individuals with HD.

  7. Assessment of coverage levels of single dose measles vaccine

    International Nuclear Information System (INIS)

    Tariq, P.

    2003-01-01

    Objective: To study the consequences of low coverage levels of a single dose of measles vaccine. Results: mean age observed in measles cases was 2 years and 8 months with a range from 3 months to 8 years. Maximum number of cases reported were <1 year of age (n=22,32%). Fifty percent of cases were seen among vaccinated children. Seventy-five percent (n=51) had history of contact with a measles case. Pneumonia was the commonest complication followed by acute gastroenteritis, encephalitis, febrile convulsions, oral ulcers, oral thrush, eye changes of vitamin-A deficiency and pulmonary tuberculosis (T.B.) in descending order of frequency. Fifty four cases were successfully treated for complications of measles and discharged. Nine cases left against medical advice. Five patients died all of them had encephalitis either alone (n=1) or in combination with pneumonia and acute gastroenteritis (n=4). Conclusion: There is a dire need to increase the immunization coverage to reduce the rate of vaccine failure and achieve effective control of measles.(author)

  8. A Brief Didactic Intervention to Improve Multiple-Choice Item-Writing Quality

    Directory of Open Access Journals (Sweden)

    Jonathan S Jones

    2018-01-01

    Full Text Available Audience: Emergency Medicine Residents, Faculty Introduction: High stakes examinations encountered throughout medical education are often composed of single best answer multiple-choice questions (MCQs. Many guidelines for writing MCQs exist, but often item writers receive little to no formal training. Flawed exam items have been shown to have lower discrimination values, potentially introducing construct-irrelevant variance to examinations, reducing their validity.1–3 Long-term faculty development in the area of item writing has been shown to improve examination item quality, with a pilot study showing that a more brief intervention had the same impact on quality of written items.4–6 Furthermore, when learners have been engaged in item writing, they have found the exercise to be a beneficial learning experience, with one study demonstrating an improved performance on a summative assessment as a result of participating in item writing.7–10 Objectives: The primary objective of this training module is to provide emergency medicine residents the basic knowledge necessary to write high quality structured single-best answer examination items through a brief, independent study format. Method: The training module is a PowerPoint-based lecture with recorded voiceover, which is provided in mp4 format.

  9. Análise de Teoria de Resposta ao Item de um instrumento breve de avaliação de comportamentos antissociais = Item Response Theory Analysis of a brief instrument for assessing antisocial behaviors

    Directory of Open Access Journals (Sweden)

    Hauck Filho, Nelson

    2014-01-01

    Full Text Available Comportamentos antissociais são comuns a diversas condições psicopatológicas, incluindo transtornos da personalidade (e. g. , antissocial e narcisista e transtornos do humor (e. g. , transtorno bipolar. Todavia, até o momento, havia uma importante lacuna no contexto brasileiro no que diz respeito à avaliação breve dos comportamentos antissociais em indivíduos adultos de contextos não carcerários. Em virtude disso, o presente estudo teve como objetivo a construção e a análise mediante Teoria de Resposta ao Item de um instrumento breve para uso em pesquisas e rastreio junto à população geral adulta. As análises das respostas de 204 estudantes universitários (média de idades = 23,56 anos; DP = 7,70; 60,6% mulheres a um conjunto de itens permitiram reter 13 itens com excelentes propriedades psicométricas. Esses itens se mostraram avaliativos de um fator geral de antissocialidade, interpretável como uma propensão ao antagonismo, à não cooperação e à agressão em uma diversidade de contextos sociais. Limitações do estudo são discutidas ao final

  10. Assessing the equivalence of web-based and paper-and-pencil questionnaires using differential item and test functioning (DIF and DTF) analysis : A case of the Four-Dimensional Symptom Questionnaire (4DSQ)

    NARCIS (Netherlands)

    Terluin, B.; Brouwers, E.P.M.; Marchand, M.A.G.; De Vet, H.C.

    2018-01-01

    Purpose: Many paper-and-pencil (P&P) questionnaires have been migrated to electronic platforms. Differential item and test functioning (DIF and DTF) analysis constitutes a superior research design to assess measurement equivalence across modes of administration. The purpose of this study was to

  11. 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.

  12. Full-Information Item Factor Analysis.

    Science.gov (United States)

    Bock, R. Darrell; And Others

    1988-01-01

    A method of item factor analysis is described, which is based on Thurstone's multiple-factor model and implemented by marginal maximum likelihood estimation and the EM algorithm. Also assessed are the statistical significance of successive factors added to the model, provisions for guessing and omitted items, and Bayes constraints. (TJH)

  13. Assessing the Equivalence of Paper, Mobile Phone, and Tablet Survey Responses at a Community Mental Health Center Using Equivalent Halves of a ‘Gold-Standard’ Depression Item Bank

    OpenAIRE

    Brodey, Benjamin B; Gonzalez, Nicole L; Elkin, Kathryn Ann; Sasiela, W Jordan; Brodey, Inger S

    2017-01-01

    Background The computerized administration of self-report psychiatric diagnostic and outcomes assessments has risen in popularity. If results are similar enough across different administration modalities, then new administration technologies can be used interchangeably and the choice of technology can be based on other factors, such as convenience in the study design. An assessment based on item response theory (IRT), such as the Patient-Reported Outcomes Measurement Information System (PROMI...

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Assessing the impact of diabetes on quality of life: validation of the Chinese version of the 19-item Audit of Diabetes-Dependent Quality of Life for Taiwan.

    Science.gov (United States)

    Wang, Huey-Fen; Bradley, Clare; Chang, Tien-Jyun; Chuang, Lee-Ming; Yeh, Mei Chang

    2017-06-01

    To examine the reliability and validity of the Chinese version of the 19-item Audit of Diabetes-Dependent Quality of Life for Taiwan (ADDQoL-CnTW). Linguistic validation procedures for patient-reported outcome measures were used to translate the Taiwan version from the original 19-item UK-English ADDQoL. The psychometric properties of the ADDQoL-CnTW were evaluated in a convenience sample, recruited from outpatient facilities, of 260 patients diagnosed with diabetes mellitus. The forced one-factor solution supported one general 19-item factor with all items loading above 0.43, accounting for 51.5% of the variance, although the results of confirmatory factory analysis did not strictly adhere to a one-factor structure. Using Kaiser's Criterion, exploratory factor analysis identified four sub-dimensions but the pattern of loading also confirmed the presence of a large general factor with 11 of 19 items loading ≥0.4 on the first component, accounting for 49.73% of the variance. Internal consistency for the entire scale was 0.94. Convergent and discriminant validity were suggested by a stronger correlation of average weighted impact (AWI) scores with the overview Diabetes-specific QoL item than with the Present QoL item. The Present QoL item correlated better with the World Health Organization Quality of Life-BREF(TW) dimension scores than the Diabetes-specific QoL scores or the AWI scores. Insulin-treated patients reported significantly more negative AWI scores and Diabetes-specific QoL scores than those treated with tablets and/or diet, demonstrating known-groups validity. The ADDQoL-CnTW revealed excellent internal consistency reliability, and showed evidence of validity for use in Taiwanese people with diabetes. © The Author 2017. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  17. Risk assessment of PCDD/Fs levels in human tissues related to major food items based on chemical analyses and micro-EROD assay.

    Science.gov (United States)

    Tsang, H L; Wu, S C; Wong, C K C; Leung, C K M; Tao, S; Wong, M H

    2009-10-01

    Nine groups of food items (freshwater fish, marine fish, pork, chicken, chicken eggs, leafy, non-leafy vegetables, rice and flour) and three types of human samples (human milk, maternal serum and cord serum) were collected for the analysis of PCDD/Fs. Results of chemical analysis revealed PCDD/Fs concentrations (pg g(-1) fat) in the following ascending order: pork (0.289 pg g(-1) fat), grass carp (Ctenopharyngodon idellus) (freshwater fish) (0.407), golden thread (Nemipterus virgatus) (marine fish) (0.511), chicken (0.529), mandarin fish (Siniperca kneri) (marine fish) (0.535), chicken egg (0.552), and snubnose pompano (Trachinotus blochii) (marine fish) (1.219). The results of micro-EROD assay showed relatively higher PCDD/Fs levels in fish (2.65 pg g(-1) fat) when compared with pork (0.47), eggs (0.33), chicken (0.13), flour (0.07), vegetables (0.05 pg g(-1) wet wt) and rice (0.05). The estimated average daily intake of PCDD/Fs of 3.51 pg EROD-TEQ/kg bw/day was within the range of WHO Tolerable Daily Intake (1-4 pg WHO-TEQ/kg bw/day) and was higher than the Provisional Tolerable Daily Intake (PMTL) (70 pg for dioxins and dioxin-like PCBs) recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) [Joint FAO/WHO Expert Committee on Food Additives (JECFA), Summary and conclusions of the fifty-seventh meeting, JECFA, 2001.]. Nevertheless, the current findings were significantly lower than the TDI (14 pg WHO-TEQ/kg/bw/day) recommended by the Scientific Committee on Food of the Europe Commission [European Scientific Committee on Food (EU SCF), Opinions on the SCF on the risk assessment of dioxins and dioxin-like PCBs in food, 2000.]. However, it should be noted that micro-EROD assay overestimates the PCDD/Fs levels by 2 to 7 folds which may also amplify the PCDD/Fs levels accordingly. Although the levels of PCDD/Fs obtained from micro-EROD assay were much higher than those obtained by chemical analysis by 2 to 7 folds, it provides a cost-effective and

  18. Differential Item Functioning Assessment in Cognitive Diagnostic Modeling: Applying the Wald Test to Investigate DIF in the Generalized DINA Model Framework

    Science.gov (United States)

    Hou, Likun

    2013-01-01

    Analyzing examinees' responses using cognitive diagnostic models (CDMs) have the advantages of providing richer diagnostic information. To ensure the validity of the results from these models, differential item functioning (DIF) in CDMs needs to be investigated. In this dissertation, the model-based DIF detection method, Wald-CDM procedure is…

  19. Test Item Development: Validity Evidence from Quality Assurance Procedures.

    Science.gov (United States)

    Downing, Steven M.; Haladyna, Thomas M.

    1997-01-01

    An ideal process is outlined for test item development and the study of item responses to ensure that tests are sound. Qualitative and quantitative methods are used to assess the item-level validity evidence for high-stakes examinations. A checklist for assessment is provided. (SLD)

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

    Science.gov (United States)

    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.

  1. Assessing the equivalence of Web-based and paper-and-pencil questionnaires using differential item and test functioning (DIF and DTF) analysis: a case of the Four-Dimensional Symptom Questionnaire (4DSQ).

    Science.gov (United States)

    Terluin, Berend; Brouwers, Evelien P M; Marchand, Miquelle A G; de Vet, Henrica C W

    2018-05-01

    Many paper-and-pencil (P&P) questionnaires have been migrated to electronic platforms. Differential item and test functioning (DIF and DTF) analysis constitutes a superior research design to assess measurement equivalence across modes of administration. The purpose of this study was to demonstrate an item response theory (IRT)-based DIF and DTF analysis to assess the measurement equivalence of a Web-based version and the original P&P format of the Four-Dimensional Symptom Questionnaire (4DSQ), measuring distress, depression, anxiety, and somatization. The P&P group (n = 2031) and the Web group (n = 958) consisted of primary care psychology clients. Unidimensionality and local independence of the 4DSQ scales were examined using IRT and Yen's Q3. Bifactor modeling was used to assess the scales' essential unidimensionality. Measurement equivalence was assessed using IRT-based DIF analysis using a 3-stage approach: linking on the latent mean and variance, selection of anchor items, and DIF testing using the Wald test. DTF was evaluated by comparing expected scale scores as a function of the latent trait. The 4DSQ scales proved to be essentially unidimensional in both modalities. Five items, belonging to the distress and somatization scales, displayed small amounts of DIF. DTF analysis revealed that the impact of DIF on the scale level was negligible. IRT-based DIF and DTF analysis is demonstrated as a way to assess the equivalence of Web-based and P&P questionnaire modalities. Data obtained with the Web-based 4DSQ are equivalent to data obtained with the P&P version.

  2. Esthetic outcome for maxillary anterior single implants assessed by different dental specialists

    OpenAIRE

    Al-Dosari, Abdullah; Al-Rowis, Ra'ed; Moslem, Feras; Alshehri, Fahad; Ballo, Ahmed M.

    2016-01-01

    PURPOSE The aim of this study was to assess the esthetic outcome of maxillary anterior single implants by comparing the esthetic perception of dental professionals and patients. MATERIALS AND METHODS Twenty-three patients with single implants in the esthetic zone were enrolled in this study. Dentists of four different dental specialties (Three orthodontists, three oral surgeons, three prosthodontists, and three periodontists) evaluated the pink esthetic score (PES)/white esthetic score (WES) ...

  3. Does the Order of Item Difficulty of the Addenbrooke's Cognitive Examination Add Anything to Subdomain Scores in the Clinical Assessment of Dementia

    Directory of Open Access Journals (Sweden)

    Sarah McGrory

    2015-04-01

    Full Text Available Background: The Addenbrooke's Cognitive Examination (ACE is used to measure cognition across a range of domains in dementia. Identifying the order in which cognitive decline occurs across items, and whether this varies between dementia aetiologies could add more information to subdomain scores. Method: ACE-Revised data from 350 patients were split into three groups: Alzheimer's type (n = 131, predominantly frontal (n = 119 and other frontotemporal lobe degenerative disorders (n = 100. Results of factor analysis and Mokken scaling analysis were compared. Results: Principal component analysis revealed one factor for each group. Confirmatory factor analysis found that the one-factor model fit two samples poorly. Mokken analyses revealed different item ordering in terms of difficulty for each group. Conclusion: The different patterns for each diagnostic group could aid in the separation of these different types of dementia.

  4. Medical Outcomes Study 36-Item Short-Form Health Survey e Health Assessment Questionnaire em mulheres submetidas à abdominoplastia em âncora após cirurgia bariátrica

    OpenAIRE

    Omonte, Ivan René Viana [UNIFESP

    2011-01-01

    Introdução: A cirurgia bariatrica tem possibilitado perda de peso com consequente excesso de pele e tela subcutanea. A abdominoplastia em ancora auxilia na melhora das deformidades resultantes da perda de peso. OBJETIVO: Avaliar a qualidade de vida e a capacidade funcional em mulheres submetidas a abdominoplastia em ancora apos cirurgia bariatrica. METODOS: Medical Outcomes Study 36-Item Short-Form Health Survey e Health Assessment Questionnaire foram utilizados para mensuracao prospectiva de...

  5. 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.

  6. Psychometric properties of three single-item pain scales in patients with rheumatoid arthritis seen during routine clinical care: a comparative perspective on construct validity, reproducibility and internal responsiveness.

    Science.gov (United States)

    Sendlbeck, Melanie; Araujo, Elizabeth G; Schett, Georg; Englbrecht, Matthias

    2015-01-01

    To investigate the construct validity, reproducibility (ie, retest reliability) and internal responsiveness to treatment change of common single-item scales measuring overall pain in patients with rheumatoid arthritis (RA) and to investigate the corresponding effect of common pain-related comorbidities and medical consultation on these outcomes. 236 patients with RA completed a set of questionnaires including a visual analogue scale (VAS), a numerical rating scale (NRS) and a verbal rating scale (VRS) measuring overall pain before and immediately after routine medical consultation as well as 1 week after the patient's visit. Construct validity and retest reliability were evaluated using the Bravais-Pearson correlation while standardised response means (SRM) were calculated for evaluating internal responsiveness. Differences in the perception of pain were calculated using dependent samples t-tests. In the total sample, construct validity was good across all three time points (convergent validity of pain scales: rT1-T3=0.82-0.92, pscales with age: rage=0.01-0.16, p>0.05). In patients maintaining antirheumatic treatment, retest reliability of pain scales was confirmed for all scales and across time points (rVAS=0.82-0.95, rNRS=0.89-0.98, rVRS=0.80-0.90, pscales to a change in treatment was low across all scales (SRM=0.08-0.21). The VAS especially suggested a change in pain perception after medical consultation in patients maintaining therapy. The VAS, NRS and VRS are valid and retest reliable in an outpatient clinical practice setting. The low pain scales' internal responsiveness to treatment change is likely to be due to the short follow-up period. Patients with RA maintaining antirheumatic therapy seem to experience less pain after medical consultation.

  7. Assessment of endogenous dopamine release by methylphenidate challenge using iodine-123 iodobenzamide single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Booij, J. [Graduate School of Neurosciences, Department of Nuclear Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Korn, P. [Graduate School of Neurosciences, Department of Nuclear Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Linszen, D.H. [Department of Psychiatry, Academic Medical Center, Tafelbergweg 25, 1105 BC Amsterdam (Netherlands); Royen, E.A. van [Graduate School of Neurosciences, Department of Nuclear Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands)

    1997-06-10

    This double-blind, placebo-controlled study assessed pharmacologically induced endogenous dopamine (DA) release in healthy male volunteers (n=12). Changes in endogenous DA release after injection of the psychostimulant drug methylphenidate were evaluated by single-photon emission tomography (SPET) and constant infusion of iodine-123 iodobenzamide ([{sup 123}I]IBZM), a D{sub 2}receptor radioligand that is sensitive to endogenous DA release. Methylphenidate induced displacement of striatal [ {sup 123}I]IBZM binding, resulting in a significantly decrease in the specific to non-specific [ {sup 123}I]IBZM uptake ratio (average: 8.6%) in comparison with placebo (average: -1.9%). Moreover, injection of methylphenidate induced significant behavioural responses on the following items: excitement, anxiety, tension, and mannerisms and posturing. The results of this study demonstrate the feasibility of using constant infusion of [ {sup 123}I]IBZM and SPET imaging to measure endogenous DA release after methylphenidate challenge and to investigate neurochemical aspects of behaviour. (orig.). With 2 figs., 1 tab.

  8. Assessment of endogenous dopamine release by methylphenidate challenge using iodine-123 iodobenzamide single-photon emission tomography

    International Nuclear Information System (INIS)

    Booij, J.; Korn, P.; Linszen, D.H.; Royen, E.A. van

    1997-01-01

    This double-blind, placebo-controlled study assessed pharmacologically induced endogenous dopamine (DA) release in healthy male volunteers (n=12). Changes in endogenous DA release after injection of the psychostimulant drug methylphenidate were evaluated by single-photon emission tomography (SPET) and constant infusion of iodine-123 iodobenzamide ([ 123 I[IBZM), a D 2 receptor radioligand that is sensitive to endogenous DA release. Methylphenidate induced displacement of striatal [ 123 I[IBZM binding, resulting in a significantly decrease in the specific to non-specific [ 123 I[IBZM uptake ratio (average: 8.6%) in comparison with placebo (average: -1.9%). Moreover, injection of methylphenidate induced significant behavioural responses on the following items: excitement, anxiety, tension, and mannerisms and posturing. The results of this study demonstrate the feasibility of using constant infusion of [ 123 I[IBZM and SPET imaging to measure endogenous DA release after methylphenidate challenge and to investigate neurochemical aspects of behaviour. (orig.). With 2 figs., 1 tab

  9. Differential item functioning by language on the PROMIS®physical functioning items for children and adolescents.

    Science.gov (United States)

    Hays, Ron D; Calderón, José Luis; Spritzer, Karen L; Reise, Steve P; Paz, Sylvia H

    2018-01-01

    To assess the equivalence of self-reports of physical functioning between pediatric respondents to the English- and Spanish-language patient-reported outcomes measurement information system (PROMIS ® ) physical functioning item banks. The PROMIS pediatric physical functioning item banks include 29 upper extremity items and 23 mobility items. A sample of 5091 children and adolescents (mean age = 12 years, range 8-17; 49% male) completed the English-language version of the items. A sample of 605 children and adolescents (mean age = 12 years, range 8-17; 55% male; 96% Hispanic) completed the Spanish-language version of the items. We found language (English versus Spanish) differential item functioning (DIF) for 4 upper extremity items and 7 mobility items. Product-moment correlations between estimated upper extremity and mobility scores using the English versus the equated Spanish item parameters for Spanish-language respondents were 0.98 and 0.99, respectively. After excluding cases with significant person misfit, we found DIF for the same 4 upper extremity items that had DIF in the full sample and for 12 mobility items (including the same 7 mobility items that had DIF in the full sample). The identification of DIF items between English- and Spanish-language respondents was affected slightly by excluding respondents displaying person misfit. The results of this study provide support for measurement equivalence of self-reports of physical functioning by children and adolescents who completed the English- and Spanish-language surveys. Future analyses are needed to replicate the results of this study in other samples.

  10. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.

  11. Exploratory Item Classification Via Spectral Graph Clustering.

    Science.gov (United States)

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

    2017-01-01

    Large-scale assessments are supported by a large item pool. An important task in test development is to assign items into scales that measure different characteristics of individuals, and a popular approach is cluster analysis of items. Classical methods in cluster analysis, such as the hierarchical clustering, K-means method, and latent-class analysis, often induce a high computational overhead and have difficulty handling missing data, especially in the presence of high-dimensional responses. In this article, the authors propose a spectral clustering algorithm for exploratory item cluster analysis. The method is computationally efficient, effective for data with missing or incomplete responses, easy to implement, and often outperforms traditional clustering algorithms in the context of high dimensionality. The spectral clustering algorithm is based on graph theory, a branch of mathematics that studies the properties of graphs. The algorithm first constructs a graph of items, characterizing the similarity structure among items. It then extracts item clusters based on the graphical structure, grouping similar items together. The proposed method is evaluated through simulations and an application to the revised Eysenck Personality Questionnaire.

  12. QAcon: single model quality assessment using protein structural and contact information with machine learning techniques.

    Science.gov (United States)

    Cao, Renzhi; Adhikari, Badri; Bhattacharya, Debswapna; Sun, Miao; Hou, Jie; Cheng, Jianlin

    2017-02-15

    Protein model quality assessment (QA) plays a very important role in protein structure prediction. It can be divided into two groups of methods: single model and consensus QA method. The consensus QA methods may fail when there is a large portion of low quality models in the model pool. In this paper, we develop a novel single-model quality assessment method QAcon utilizing structural features, physicochemical properties, and residue contact predictions. We apply residue-residue contact information predicted by two protein contact prediction methods PSICOV and DNcon to generate a new score as feature for quality assessment. This novel feature and other 11 features are used as input to train a two-layer neural network on CASP9 datasets to predict the quality of a single protein model. We blindly benchmarked our method QAcon on CASP11 dataset as the MULTICOM-CLUSTER server. Based on the evaluation, our method is ranked as one of the top single model QA methods. The good performance of the features based on contact prediction illustrates the value of using contact information in protein quality assessment. The web server and the source code of QAcon are freely available at: http://cactus.rnet.missouri.edu/QAcon. chengji@missouri.edu. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  13. Content Coverage of Single-Word Tests Used to Assess Common Phonological Error Patterns

    Science.gov (United States)

    Kirk, Cecilia; Vigeland, Laura

    2015-01-01

    Purpose: This review evaluated whether 9 single-word tests of phonological error patterns provide adequate content coverage to accurately identify error patterns that are active in a child's speech. Method: Tests in the current study were considered to display sufficient opportunities to assess common phonological error patterns if they…

  14. Validation of the 36-item version of the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) for assessing women's disability and functioning associated with maternal morbidity.

    Science.gov (United States)

    Silveira, Carla; Parpinelli, Mary Angela; Pacagnella, Rodolfo Carvalho; Andreucci, Carla Betina; Angelini, Carina Robles; Ferreira, Elton Carlos; Cecatti, José Guilherme

    2017-02-01

    Objective  To validate the translation and adaptation to Brazilian Portuguese of 36 items from the World Health Organizaton Disability Assessment Schedule 2.0 (WHODAS 2.0), regarding their content and structure (construct), in a female population after pregnancy. Methods  This is a validation of an instrument for the evaluation of disability and functioning and an assessment of its psychometric properties, performed in a tertiary maternity and a referral center specialized in high-risk pregnancies in Brazil. A sample of 638 women in different postpartum periods who had either a normal or a complicated pregnancy was included. The structure was evaluated by exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), while the content and relationships among the domains were assessed through Pearson's correlation coefficient. The sociodemographic characteristics were identified, and the mean scores with their standard deviations for the 36 questions of the WHODAS 2.0 were calculated. The internal consistency was evaluated byCronbach's α. Results  Cronbach's α was higher than 0.79 for both sets of questons of the questionnaire. The EFA and CFA for the main 32 questions exhibited a total variance of 54.7% (Kaiser-Meyer-Olkin [KMO] measure of sampling adequacy =  0.934; p  WHODAS 2.0 instrument adapted to Brazilian Portuguese showed good psychometric properties in this sample, and therefore could be applied to populations of women regarding their reproductive history. Thieme-Revinter Publicações Ltda Rio de Janeiro, Brazil.

  15. Item Banking with Embedded Standards

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  18. 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.

  19. Vegetable parenting practices scale: Item response modeling analyses

    Science.gov (United States)

    Our objective was to evaluate the psychometric properties of a vegetable parenting practices scale using multidimensional polytomous item response modeling which enables assessing item fit to latent variables and the distributional characteristics of the items in comparison to the respondents. We al...

  20. SHIPPING OF RADIOACTIVE ITEMS

    CERN Document Server

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.

  1. Assessment of BNP Level in Patients with Single Chamber and Dual Chamber Pacemakers

    Directory of Open Access Journals (Sweden)

    J Kojuri

    2010-09-01

    Full Text Available Background: Recent years, have witnessed extended and continuous indication of cardiac pacing. However, increasing number of patients suffered new congestive heart failure (CHF and aggravated CHF after pacing therapy. We used blood B type nutriuretic peptide (BNP to predict the occurrence of CHF in patients with different types of pacemakers. To assess single N-terminal brain nutriuretic peptide (NT-pro BNP as a predictor tool for ventricular dysfunction in different cardiac pacing mode.Methods: Out of 480 consecutive patients with pacemaker more than 6 months, 79 patients with average age of 65±13, and more than 90% ventricular pacing participated in the present study. Those with CHF prior to pacemaker insertion were excluded. The patients underwent medical history and examination, echocardiography (M-mode, Doppler, and Tissue imaging and blood sampling for pro-BNP. Twenty five, 12, and 42 patients had Dual chamber (DDDR, single chamber pacing with dual chamber sensing ( VDDR, and Single chamber (VVIR pacemakers respectivelyResults: Single pro-BNP level in patient with DDDR and VDDR pacing was lower than in those with VVIR pacing (P< 0.0001 but in Echocardiography left ventricular (LV dysfunction was not lower in DDDR than VDDR and VVIR pacing patients (P= 0.190. Conclusion: Single level of pro-BNP is lower in double chamber pacing in comparison with single chamber pacing. Therefore, it seems that dual chamber pacing causes less LV dysfunction.

  2. Applying the Longitudinal Model from Item Response Theory to Assess Health-Related Quality of Life in the PRODIGE 4/ACCORD 11 Randomized Trial.

    Science.gov (United States)

    Barbieri, Antoine; Anota, Amélie; Conroy, Thierry; Gourgou-Bourgade, Sophie; Juzyna, Beata; Bonnetain, Franck; Lavergne, Christian; Bascoul-Mollevi, Caroline

    2016-07-01

    A new longitudinal statistical approach was compared to the classical methods currently used to analyze health-related quality-of-life (HRQoL) data. The comparison was made using data in patients with metastatic pancreatic cancer. Three hundred forty-two patients from the PRODIGE4/ACCORD 11 study were randomly assigned to FOLFIRINOX versus gemcitabine regimens. HRQoL was evaluated using the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30. The classical analysis uses a linear mixed model (LMM), considering an HRQoL score as a good representation of the true value of the HRQoL, following EORTC recommendations. In contrast, built on the item response theory (IRT), our approach considered HRQoL as a latent variable directly estimated from the raw data. For polytomous items, we extended the partial credit model to a longitudinal analysis (longitudinal partial credit model [LPCM]), thereby modeling the latent trait as a function of time and other covariates. Both models gave the same conclusions on 11 of 15 HRQoL dimensions. HRQoL evolution was similar between the 2 treatment arms, except for the symptoms of pain. Indeed, regarding the LPCM, pain perception was significantly less important in the FOLFIRINOX arm than in the gemcitabine arm. For most of the scales, HRQoL changes over time, and no difference was found between treatments in terms of HRQoL. The use of LMM to study the HRQoL score does not seem appropriate. It is an easy-to-use model, but the basic statistical assumptions do not check. Our IRT model may be more complex but shows the same qualities and gives similar results. It has the additional advantage of being more precise and suitable because of its direct use of raw data. © The Author(s) 2015.

  3. An analysis of differential item functioning by gender in the Learning Disability Screening Questionnaire (LDSQ).

    Science.gov (United States)

    Murray, Aja Louise; Booth, Tom; McKenzie, Karen

    2015-04-01

    The Learning Disability Screening Questionnaire (LDSQ; McKenzie & Paxton, 2006) was developed as a brief screen for intellectual disability. Although several previous studies have evaluated the LDSQ with respect to its utility as a clinical and research tool, no studies have considered the fairness of the test across males and females. In the current study we, therefore, used a multi-group item response theory approach to assess differential item functioning across gender in a sample of 211 males and 132 females assessed in clinical and forensic settings. Although the test did not show evidence of differential item functioning by gender, it was necessary to exclude one item due to estimation problems and to combine two very highly related items (concerning reading and writing ability) into a single literacy item Thus, in addition to being generally supportive of the utility of the LDSQ, our results also highlight possible areas of weakness in the tool and suggest possible amendments that could be made to test content to improve the test in future revisions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The MCRA model for probabilistic single-compound and cumulative risk assessment of pesticides.

    Science.gov (United States)

    van der Voet, Hilko; de Boer, Waldo J; Kruisselbrink, Johannes W; Goedhart, Paul W; van der Heijden, Gerie W A M; Kennedy, Marc C; Boon, Polly E; van Klaveren, Jacob D

    2015-05-01

    Pesticide risk assessment is hampered by worst-case assumptions leading to overly pessimistic assessments. On the other hand, cumulative health effects of similar pesticides are often not taken into account. This paper describes models and a web-based software system developed in the European research project ACROPOLIS. The models are appropriate for both acute and chronic exposure assessments of single compounds and of multiple compounds in cumulative assessment groups. The software system MCRA (Monte Carlo Risk Assessment) is available for stakeholders in pesticide risk assessment at mcra.rivm.nl. We describe the MCRA implementation of the methods as advised in the 2012 EFSA Guidance on probabilistic modelling, as well as more refined methods developed in the ACROPOLIS project. The emphasis is on cumulative assessments. Two approaches, sample-based and compound-based, are contrasted. It is shown that additional data on agricultural use of pesticides may give more realistic risk assessments. Examples are given of model and software validation of acute and chronic assessments, using both simulated data and comparisons against the previous release of MCRA and against the standard software DEEM-FCID used by the Environmental Protection Agency in the USA. It is shown that the EFSA Guidance pessimistic model may not always give an appropriate modelling of exposure. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  5. Qualitative and quantitative assessment of single fingerprints in forensic DNA analysis.

    Science.gov (United States)

    Ostojic, Lana; Klempner, Stacey A; Patel, Rosni A; Mitchell, Adele A; Axler-DiPerte, Grace L; Wurmbach, Elisa

    2014-11-01

    Fingerprints and touched items are important sources of DNA for STR profiling, since this evidence can be recovered in a wide variety of criminal offenses. However, there are some fundamental difficulties in working with these samples, including variability in quantity and quality of extracted DNA. In this study, we collected and analyzed over 700 fingerprints. We compared a commercially available extraction protocol (Zygem) to two methods developed in our laboratory, a simple one-tube protocol and a high sensitivity protocol (HighSens) that includes additional steps to concentrate and purify the DNA. The amplification protocols tested were AmpFLSTR® Identifiler® using either 28 or 31 amplification cycles, and Identifiler® Plus using 32 amplification cycles. We found that the HighSens and Zygem extraction methods were significantly better in their DNA yields than the one-tube method. Identifiler® Plus increased the quality of the STR profiles for the one-tube extraction significantly. However, this effect could not be verified for the other extraction methods. Furthermore, microscopic analysis of single fingerprints revealed that some individuals tended to shed more material than others onto glass slides. However, a dense deposition of skin flakes did not strongly correlate with a high quality STR profile. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Analysis of Item Difficulty Parameters on Item Characteristic Curves ...

    African Journals Online (AJOL)

    Analysis of Item Difficulty Parameters on Item Characteristic Curves as A Function of Changes in WAEC and NECO Examination Instruments and Students Ability Parameters in Mathematics Objective Test in Cross River State, Nigeria.

  7. Reliability Assessment of a Single-Shot System by Use of Screen Test Results

    Science.gov (United States)

    2018-02-01

    unlimited. NUWC Keyport #17-002. Reliability Assessment of a Single-Shot System by Use of Screen Test Results Abstract: Field reliability prediction...approach described here assumes that the defect density during testing takes the form of an exponential decay, although other mathematical functions can...be substituted for the exponential. In order to apply the decay rate function to a discrete pass/fail test scheme, the approach provides for

  8. Real and Artificial Differential Item Functioning in Polytomous Items

    Science.gov (United States)

    Andrich, David; Hagquist, Curt

    2015-01-01

    Differential item functioning (DIF) for an item between two groups is present if, for the same person location on a variable, persons from different groups have different expected values for their responses. Applying only to dichotomously scored items in the popular Mantel-Haenszel (MH) method for detecting DIF in which persons are classified by…

  9. How employees perceive organizational learning: construct validation of the 25-item short form of the strategic learning assessment map (SF-SLAM)

    NARCIS (Netherlands)

    Mainert, Jakob; Niepel, Christoph; Lans, T.; Greiff, Samuel

    2018-01-01

    Purpose: The Strategic Learning Assessment Map (SLAM) originally assessed organizational learning (OL) at the level of the firm by addressing managers, who rated OL in the SLAM on five dimensions of individual learning, group learning, organizational learning, feed-forward learning, and feedback

  10. Examination of the PROMIS upper extremity item bank.

    Science.gov (United States)

    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.

  11. SVMQA: support-vector-machine-based protein single-model quality assessment.

    Science.gov (United States)

    Manavalan, Balachandran; Lee, Jooyoung

    2017-08-15

    The accurate ranking of predicted structural models and selecting the best model from a given candidate pool remain as open problems in the field of structural bioinformatics. The quality assessment (QA) methods used to address these problems can be grouped into two categories: consensus methods and single-model methods. Consensus methods in general perform better and attain higher correlation between predicted and true quality measures. However, these methods frequently fail to generate proper quality scores for native-like structures which are distinct from the rest of the pool. Conversely, single-model methods do not suffer from this drawback and are better suited for real-life applications where many models from various sources may not be readily available. In this study, we developed a support-vector-machine-based single-model global quality assessment (SVMQA) method. For a given protein model, the SVMQA method predicts TM-score and GDT_TS score based on a feature vector containing statistical potential energy terms and consistency-based terms between the actual structural features (extracted from the three-dimensional coordinates) and predicted values (from primary sequence). We trained SVMQA using CASP8, CASP9 and CASP10 targets and determined the machine parameters by 10-fold cross-validation. We evaluated the performance of our SVMQA method on various benchmarking datasets. Results show that SVMQA outperformed the existing best single-model QA methods both in ranking provided protein models and in selecting the best model from the pool. According to the CASP12 assessment, SVMQA was the best method in selecting good-quality models from decoys in terms of GDTloss. SVMQA method can be freely downloaded from http://lee.kias.re.kr/SVMQA/SVMQA_eval.tar.gz. jlee@kias.re.kr. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  12. Inversion recovery single-shot TurboFLASH for assessment of myocardial infarction at 3 Tesla.

    Science.gov (United States)

    Bauner, Kerstin U; Muehling, Olaf; Wintersperger, Bernd J; Winnik, Eva; Reiser, Maximilian F; Huber, Armin

    2007-06-01

    The aim of the study was to assess the diagnostic accuracy of imaging myocardial infarction with a single-shot inversion recovery turbofast low-angle shot (SS IR turboFLASH) sequence at 3.0 Tesla in comparison with an established segmented inversion recovery turboFLASH sequence at 1.5 Tesla. Fifteen patients with myocardial infarction were examined at a 1.5 Tesla magnetic resonance (MR) System (Avanto, Siemens, Medical Solutions) and at a 3.0 Tesla MR system (TIM Trio, Siemens, Medical Solutions). Imaging delayed enhancement was started 15 minutes after application of contrast material. A SS IR turboFLASH was performed at 3.0 Tesla and compared with a segmented IR turboFLASH sequence at 1.5 and at 3.0 Tesla. The IR turboFLASH sequence at 1.5 Tesla served as reference method. Infarct volumes, contrast/noise ratio (CNR) of infarcted and normal myocardium were compared with the reference method. The Single-Shot IR turboFLASH technique allows imaging 9 slices during a single breath-hold. The CNR between infarction and normal myocardium of the reference method was 6.4 at 1.5 Tesla. The mean value of CNR of the IR turboFLASH sequence was 7.3 at 3.0 Tesla for the single-shot technique and 14.1 at 3.0 Tesla for the segmented technique. No significant difference was found for the CNR values of the reference technique at 1.5 Tesla and the single-shot technique at 3.0 Tesla, however for the comparison of the segmented technique at 1.5 and at 3 Tesla (P = 0.0001). The correlation coefficients of the infarct volumes, determined with the Single-Shot IR turboFLASH and the segmented IR turboFLASH technique at 3.0 compared with the reference method, were r = 0.95 (P < 0.0001) and r = 0.95 (P < 0.0001). The loss of CNR, which is caused by replacement of the segmented technique by the single-shot technique, is completely compensated by the approximately 2-fold CNR increase at the higher field strength. The IR turboFLASH technique at 3.0 Tesla IR can be used as a single-shot technique

  13. The Development and Evaluation of an Online Formative Assessment upon Single-Player Game in E-Learning Environment

    Science.gov (United States)

    Tsai, Fu-Hsing

    2013-01-01

    This study developed a game-based formative assessment, called tic-tac-toe quiz for single-player version (TRIS-Q-SP), in an energy education e-learning system. This assessment game combined tic-tac-toe with online assessment, and revised the rule of tic-tac-toe for stimulating students to use online formative assessment actively. Additionally, to…

  14. A Multi-techniques Approach to assess reprocessing of Single-use electrosurgical pencils.

    Science.gov (United States)

    Tessarolo, Francesco; Torres, Sebastian; Ballesteros, Luis; Rigoni, Marta; Piccoli, Federico; Caola, Iole; Montoya, Yesid; Nollo, Giandomenico

    2015-01-01

    Reprocessing and reuse of single-use electrosurgical pencils (EPs) is a diffused practice in countries with limited access to healthcare subvention system and in developing countries. However, safety and efficacy issues are associated to this practice, requiring specific methods for checking the reprocessed device before clinical re-use. This study aimed at defining a set of testing methods for assessing thermal and surface characteristics of reprocessed single-use EPs and evaluating the suitability of these techniques for revealing modifications between brand new and reprocessed single-use EPs. We reported a multi-technique approach based on optical and electron microscopy, X-rays spectroscopy and thermal analysis. The assessment of a total of 30 variables of interest on both brand new and reprocessed devices, allowed to identify the most informative ones. Seven of the evaluated variables were found to differentiate the reprocessed device from the new ones in a significant way. The presented methods deserve potential for tracking modifications during the device lifecycle.

  15. Assessing the anomalous superdiffusive heat transport in a single one-dimensional PEDOT chain

    Science.gov (United States)

    Crnjar, Alessandro; Melis, Claudio; Colombo, Luciano

    2018-01-01

    We present a computational investigation on heat transport in a single polymer chain of poly-3,4-ethylenedioxythiophene (PEDOT). By applying equilibrium and nonequilibrium molecular dynamics simulations to evaluate the thermal conductivity, as well as by investigating how the polymer chain approaches equilibrium upon a local thermal excitation, we provide a robust picture assessing the anomalous superdiffusive (i.e., intermediate between ballistic and diffusive) character of its thermal transport. This assessment is provided by the present simulations showing that three scaling laws with unlike physical meaning and characterizing the thermal energy transport in one-dimensional systems indeed occur in the very same polymer chain with consistent critical exponents. In order to disentangle the effect of dimensionality, we perform a systematic comparison of transport features for a single one-dimensional (1D) PEDOT chain and a three-dimensional (3D) PEDOT crystal. Present simulations suggest that by increasing the dimensionality, the anomalous regime is completely removed as due to the occurrence of strong interchains anharmonic interactions. Finally, we prove that thermal transport in isolated single PEDOT chains belongs to a novel universality class of superdiffusion characterized by a critical exponent β =1 /2 .

  16. Laryngopharyngeal reflux: a prospective analysis of a 34 item symptom questionnaire.

    Science.gov (United States)

    Papakonstantinou, L; Leslie, P; Gray, J; Chadwick, T; Hudson, M; Wilson, J A

    2009-10-01

    Laryngopharyngeal reflux is increasingly diagnosed, but both its symptoms and relationship to gastro-oesophageal reflux disease remain confused. (i) To assess symptoms in potential laryngopharyngeal reflux patients according to a comprehensive symptom list based on both a gastro-oesophageal reflux questionnaire and a laryngopharyngeal reflux questionnaire. (ii) To assess whether there are statistically discrete symptom clusters which might map to specific syndromes e.g. globus pharynges. Prospective single cohort questionnaire survey. A 34-item questionnaire comprising all symptoms identifiable on (i) the original 25-item Gastroesophageal Symptom Assessment Scale (GSAS) and (ii) the nine Reflux Symptom Index (RSI) items, 'unbundled' as necessary, were administered to 62 ENT clinic attenders. Descriptive, correlation and cluster analysis was performed. All but two of the combined 34-symptom list were endorsed by at least 20% of 62 patients. Certain symptoms which the Reflux Symptom Index groups as a single item were only weakly correlated. No specific symptom clusters were identified. Neither the most popular 'lower' oesophageal (GSAS) nor the 'throat' reflux (RSI) questionnaire adequately captures the full range of potential reflux symptoms regularly encountered in otolaryngology patients: inadequate evaluation of patients' symptoms may have contributed to the ongoing uncertainty about the role of acid or pepsin suppression. A more comprehensive reflux questionnaire is needed to characterise the true reflux correlations of laryngopharyngeal symptoms, and offer a symptom-specific measure of response to placebo and anti-reflux therapy.

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

    Science.gov (United States)

    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.

  18. Negative Affect Impairs Associative Memory but Not Item Memory

    Science.gov (United States)

    Bisby, James A.; Burgess, Neil

    2014-01-01

    The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine…

  19. Respiratory Symptoms Items from the COPD Assessment Test Identify Ever-Smokers with Preserved Lung Function at Higher Risk for Poor Respiratory Outcomes. An Analysis of the Subpopulations and Intermediate Outcome Measures in COPD Study Cohort.

    Science.gov (United States)

    Martinez, Carlos H; Murray, Susan; Barr, R Graham; Bleecker, Eugene; Bowler, Russell P; Christenson, Stephanie A; Comellas, Alejandro P; Cooper, Christopher B; Couper, David; Criner, Gerard J; Curtis, Jeffrey L; Dransfield, Mark T; Hansel, Nadia N; Hoffman, Eric A; Kanner, Richard E; Kleerup, Eric; Krishnan, Jerry A; Lazarus, Stephen C; Leidy, Nancy K; O'Neal, Wanda; Martinez, Fernando J; Paine, Robert; Rennard, Stephen I; Tashkin, Donald P; Woodruff, Prescott G; Han, MeiLan K

    2017-05-01

    Ever-smokers without airflow obstruction scores greater than or equal to 10 on the COPD Assessment Test (CAT) still have frequent acute respiratory disease events (exacerbation-like), impaired exercise capacity, and imaging abnormalities. Identification of these subjects could provide new opportunities for targeted interventions. We hypothesized that the four respiratory-related items of the CAT might be useful for identifying such individuals, with discriminative ability similar to CAT, which is an eight-item questionnaire used to assess chronic obstructive pulmonary disease impact, including nonrespiratory questions, with scores ranging from 0 to 40. We evaluated ever-smoker participants in the Subpopulations and Intermediate Outcomes in COPD Study without airflow obstruction (FEV 1 /FVC ≥0.70; FVC above the lower limit of normal). Using the area under the receiver operating characteristic curve, we compared responses to both CAT and the respiratory symptom-related CAT items (cough, phlegm, chest tightness, and breathlessness) and their associations with longitudinal exacerbations. We tested agreement between the two strategies (κ statistic), and we compared demographics, lung function, and symptoms among subjects identified as having high symptoms by each strategy. Among 880 ever-smokers with normal lung function (mean age, 61 yr; 52% women) and using a CAT cutpoint greater than or equal to 10, we classified 51.8% of individuals as having high symptoms, 15.3% of whom experienced at least one exacerbation during 1-year follow-up. After testing sensitivity and specificity of different scores for the first four questions to predict any 1-year follow-up exacerbation, we selected cutpoints of 0-6 as representing a low burden of symptoms versus scores of 7 or higher as representing a high burden of symptoms for all subsequent comparisons. The four respiratory-related items with cutpoint greater than or equal to 7 selected 45.8% participants, 15.6% of whom

  20. The 12-item Self-Report World Health Organization Disability Assessment Schedule (WHODAS) 2.0 Administered Via the Internet to Individuals With Anxiety and Stress Disorders: A Psychometric Investigation Based on Data From Two Clinical Trials.

    Science.gov (United States)

    Axelsson, Erland; Lindsäter, Elin; Ljótsson, Brjánn; Andersson, Erik; Hedman-Lagerlöf, Erik

    2017-12-08

    The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) is a widespread measure of disability and functional impairment, which is bundled with the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) for use in psychiatry. Administering psychometric scales via the Internet is an effective way to reach respondents and allow for convenient handling of data. The aim was to study the psychometric properties of the 12-item self-report WHODAS 2.0 when administered online to individuals with anxiety and stress disorders. The WHODAS 2.0 was hypothesized to exhibit high internal consistency and be unidimensional. We also expected the WHODAS 2.0 to show high 2-week test-retest reliability, convergent validity (correlations approximately .50 to .90 with other self-report measures of functional impairment), that it would differentiate between patients with and without exhaustion disorder, and that it would respond to change in primary symptom domain. We administered the 12-item self-report WHODAS 2.0 online to patients with anxiety and stress disorders (N=160) enrolled in clinical trials of cognitive behavior therapy, and analyzed psychometric properties within a classical test theory framework. Scores were compared with well-established symptom and disability measures, and sensitivity to change was studied from pretreatment to posttreatment assessment. The 12-item self-report WHODAS 2.0 showed high internal consistency (Cronbach alpha=.83-.92), high 2-week test-retest reliability (intraclass correlation coefficient=.83), adequate construct validity, and was sensitive to change. We found preliminary evidence for a three-factorial structure, but one strong factor accounted for a clear majority of the variance. We conclude that the 12-item self-report WHODAS 2.0 is a psychometrically sound instrument when administered online to individuals with anxiety and stress disorders, but that it is probably fruitful to also report the three

  1. Sources of interference in item and associative recognition memory.

    Science.gov (United States)

    Osth, Adam F; Dennis, Simon

    2015-04-01

    A powerful theoretical framework for exploring recognition memory is the global matching framework, in which a cue's memory strength reflects the similarity of the retrieval cues being matched against the contents of memory simultaneously. Contributions at retrieval can be categorized as matches and mismatches to the item and context cues, including the self match (match on item and context), item noise (match on context, mismatch on item), context noise (match on item, mismatch on context), and background noise (mismatch on item and context). We present a model that directly parameterizes the matches and mismatches to the item and context cues, which enables estimation of the magnitude of each interference contribution (item noise, context noise, and background noise). The model was fit within a hierarchical Bayesian framework to 10 recognition memory datasets that use manipulations of strength, list length, list strength, word frequency, study-test delay, and stimulus class in item and associative recognition. Estimates of the model parameters revealed at most a small contribution of item noise that varies by stimulus class, with virtually no item noise for single words and scenes. Despite the unpopularity of background noise in recognition memory models, background noise estimates dominated at retrieval across nearly all stimulus classes with the exception of high frequency words, which exhibited equivalent levels of context noise and background noise. These parameter estimates suggest that the majority of interference in recognition memory stems from experiences acquired before the learning episode. (c) 2015 APA, all rights reserved).

  2. What We Don't Test: What an Analysis of Unreleased ACS Exam Items Reveals about Content Coverage in General Chemistry Assessments

    Science.gov (United States)

    Reed, Jessica J.; Villafan~e, Sachel M.; Raker, Jeffrey R.; Holme, Thomas A.; Murphy, Kristen L.

    2017-01-01

    General chemistry courses are often the foundation for the study of other science disciplines and upper-level chemistry concepts. Students who take introductory chemistry courses are more often from health and science-related fields than chemistry. As such, the content taught and assessed in general chemistry courses is envisioned as building…

  3. Tremor magnitude: a single index to assess writing and drawing in essential tremor.

    Science.gov (United States)

    Ulmanová, Olga; Homann, Carl Nikolaus; Ulman, Radek; Jech, Robert; Capek, Václav; Klempír, Jirí; Růzicka, Evzen

    2007-05-01

    Hand tremor often causes disability in patients with essential tremor (ET). Aim of the study was to investigate whether tremor magnitude, a new single quantitative score obtained from digital tablet recordings of writing and drawing, is able to adequately reflect disability in ET patients. Mean tremor magnitude values showed significant difference between 14 ET patients and 14 healthy age matched controls (p<0.0001). The tremor magnitude values showed significant correlation with standard methods of clinical assessment (p<0.01). We present tremor magnitude as an index that reflects disability resulting from tremor and can help to evaluate ET.

  4. RCRA Assessment Plan for Single-Shell Tank Waste Management Area TX-TY

    Energy Technology Data Exchange (ETDEWEB)

    Horton, Duane G.

    2007-03-26

    WMA TX-TY contains underground, single-shell tanks that were used to store liquid waste that contained chemicals and radionuclides. Most of the liquid has been removed, and the remaining waste is regulated under the RCRA as modi¬fied in 40 CFR Part 265, Subpart F and Washington State’s Hazardous Waste Management Act . WMA TX-TY was placed in assessment monitoring in 1993 because of elevated specific conductance. A groundwater quality assessment plan was written in 1993 describing the monitoring activities to be used in deciding whether WMA TX-TY had affected groundwater. That plan was updated in 2001 for continued RCRA groundwater quality assessment as required by 40 CFR 265.93 (d)(7). This document further updates the assessment plan for WMA TX-TY by including (1) information obtained from ten new wells installed at the WMA after 1999 and (2) information from routine quarterly groundwater monitoring during the last five years. Also, this plan describes activities for continuing the groundwater assessment at WMA TX TY.

  5. Item response theory at subject- and group-level

    NARCIS (Netherlands)

    Tobi, Hilde

    1990-01-01

    This paper reviews the literature about item response models for the subject level and aggregated level (group level). Group-level item response models (IRMs) are used in the United States in large-scale assessment programs such as the National Assessment of Educational Progress and the California

  6. THE VISUAL METHOD IN QUALITY ASSESSMENT OF SINGLE-LAP ADHESIVE JOINTS

    Directory of Open Access Journals (Sweden)

    Anna Rudawska

    2016-09-01

    Full Text Available This article presents selected criteria for the quality assessment of single-lap adhesive joints formed on 0.66±0.04 thick hot dip zinc coated sheets with the hot dip zinc coating thickness equal to 18 µm. Three types of epoxy adhesives and three variants of the mass of adhesives were tested (1 g, 2 g and 3 g. The work intended to assess the capacity of the visual method with regard to evaluating joint quality, allowing for the presence and the size of spew fillet, joint dimensions and the effect of spew fillet on adhesive joint strength. The strength of analysed adhesive joints was determined in destructive tests.

  7. Single-cell-based evaluation of sperm progressive motility via fluorescent assessment of mitochondria membrane potential.

    Science.gov (United States)

    Moscatelli, Natalina; Spagnolo, Barbara; Pisanello, Marco; Lemma, Enrico Domenico; De Vittorio, Massimo; Zara, Vincenzo; Pisanello, Ferruccio; Ferramosca, Alessandra

    2017-12-20

    Sperm cells progressive motility is the most important parameter involved in the fertilization process. Sperm middle piece contains mitochondria, which play a critical role in energy production and whose proper operation ensures the reproductive success. Notably, sperm progressive motility is strictly related to mitochondrial membrane potential (MMP) and consequently to mitochondrial functionality. Although previous studies presented an evaluation of mitochondrial function through MMP assessment in entire sperm cells samples, a quantitative approach at single-cell level could provide more insights in the analysis of semen quality. Here we combine laser scanning confocal microscopy and functional fluorescent staining of mitochondrial membrane to assess MMP distribution among isolated spermatozoa. We found that the sperm fluorescence value increases as a function of growing progressive motility and that such fluorescence is influenced by MMP disruptors, potentially allowing for the discrimination of different quality classes of sperm cells in heterogeneous populations.

  8. Thin slices of creativity: using single-word utterances to assess creative cognition.

    Science.gov (United States)

    Prabhakaran, Ranjani; Green, Adam E; Gray, Jeremy R

    2014-09-01

    We investigated the hypothesis that individual differences in creative cognition can be manifest even in brief responses, such as single-word utterances. Participants (n = 193) were instructed to say a verb upon seeing a noun displayed on a computer screen and were cued to respond creatively to half of the nouns. For every noun-verb pair (72 pairs per subject), we assessed the semantic distance between the noun and the verb, using latent semantic analysis (LSA). Semantic distance was higher in the cued ("creative") condition than the uncued condition, within subjects. Critically, between subjects, semantic distance in the cued condition had a strong relationship to a creativity factor derived from a battery of verbal, nonverbal, and achievement-based creativity measures (β= .50), and this relation remained when controlling for intelligence and personality. The data show that creative cognition can be assessed reliably and validly from such thin slices of behavior.

  9. An Assessment of Reduced Crew and Single Pilot Operations in Commercial Transport Aircraft Operations

    Science.gov (United States)

    Bailey, Randall E.; Kramer, Lynda J.; Kennedy, Kellie D.; Stephens, Chad L.; Etherington, Timothy J.

    2017-01-01

    Future reduced crew operations or even single pilot operations for commercial airline and on-demand mobility applications are an active area of research. These changes would reduce the human element and thus, threaten the precept that "a well-trained and well-qualified pilot is the critical center point of aircraft systems safety and an integral safety component of the entire commercial aviation system." NASA recently completed a pilot-in-the-loop high fidelity motion simulation study in partnership with the Federal Aviation Administration (FAA) attempting to quantify the pilot's contribution to flight safety during normal flight and in response to aircraft system failures. Crew complement was used as the experiment independent variable in a between-subjects design. These data show significant increases in workload for single pilot operations, compared to two-crew, with subjective assessments of safety and performance being significantly degraded as well. Nonetheless, in all cases, the pilots were able to overcome the failure mode effects in all crew configurations. These data reflect current-day flight deck equipage and help identify the technologies that may improve two-crew operations and/or possibly enable future reduced crew and/or single pilot operations.

  10. Psychometric properties and a latent class analysis of the 12-item World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) in a pooled dataset of community samples.

    Science.gov (United States)

    MacLeod, Melissa A; Tremblay, Paul F; Graham, Kathryn; Bernards, Sharon; Rehm, Jürgen; Wells, Samantha

    2016-12-01

    The 12-item World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) is a brief measurement tool used cross-culturally to capture the multi-dimensional nature of disablement through six domains, including: understanding and interacting with the world; moving and getting around; self-care; getting on with people; life activities; and participation in society. Previous psychometric research supports that the WHODAS 2.0 functions as a general factor of disablement. In a pooled dataset from community samples of adults (N = 447) we used confirmatory factor analysis to confirm a one-factor structure. Latent class analysis was used to identify subgroups of individuals based on their patterns of responses. We identified four distinct classes, or patterns of disablement: (1) pervasive disability; (2) physical disability; (3) emotional, cognitive, or interpersonal disability; (4) no/low disability. Convergent validity of the latent class subgroups was found with respect to socio-demographic characteristics, number of days affected by disabilities, stress, mental health, and substance use. These classes offer a simple and meaningful way to classify people with disabilities based on the 12-item WHODAS 2.0. Focusing on individuals with a high probability of being in the first three classes may help guide interventions. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Diagnostic Efficacy of a Single Progesterone Determination to Assess Full-Term Pregnancy in the Bitch.

    Science.gov (United States)

    Rota, A; Charles, C; Starvaggi Cucuzza, A; Pregel, P

    2015-12-01

    In clinical settings, when the reproductive history of a near-term bitch is limited to mating dates, the possibility to accurately assess whether pregnancy is at term could be very useful in order to be able to plan a correct management of parturition or to safely perform an elective Caesarean section. The aim of this study was to assess the diagnostic efficacy of a single progesterone determination, measured by chemiluminescent immunoassay (CLIA), in predicting the occurrence of parturition on the following day. At least one blood sample was collected from 51 pre-partum bitches during the 3 days before parturition and on day of parturition. The efficacy of progesterone as a marker of the end of pregnancy was tested using a receiver operating characteristic (ROC) analysis. Youden's index was calculated to select the optimal cut-off value (with 95% confidence interval), aiming at maximizing the correct identification of negative events, so not to risk to diagnose as full term a bitch which is not. Progesterone concentration lower than 3.4 ng/ml correctly identified the bitches whelping the following day; however, because of the obliged prudential approach, sensitivity was low (46.88%), and 17 of 32 full-term bitches were missed. Due to a very large individual variation, a single progesterone determination has low diagnostic efficacy, although it can represent a useful first screening. © 2015 Blackwell Verlag GmbH.

  12. Linking Item Response Model Parameters.

    Science.gov (United States)

    van der Linden, Wim J; Barrett, Michelle D

    2016-09-01

    With a few exceptions, the problem of linking item response model parameters from different item calibrations has been conceptualized as an instance of the problem of test equating scores on different test forms. This paper argues, however, that the use of item response models does not require any test score equating. Instead, it involves the necessity of parameter linking due to a fundamental problem inherent in the formal nature of these models-their general lack of identifiability. More specifically, item response model parameters need to be linked to adjust for the different effects of the identifiability restrictions used in separate item calibrations. Our main theorems characterize the formal nature of these linking functions for monotone, continuous response models, derive their specific shapes for different parameterizations of the 3PL model, and show how to identify them from the parameter values of the common items or persons in different linking designs.

  13. Model Penjadwalan Batch Multi Item dengan Dependent Processing Time

    Directory of Open Access Journals (Sweden)

    Sukoyo Sukoyo

    2010-01-01

    Full Text Available This paper investigates a development of single machine batch scheduling for multi items with dependent processing time. The batch scheduling problem is to determine simultaneously number of batch (N, which item and its size allocated for each batch, and processing sequences of resulting batches. We use total actual flow time as the objective of schedule performance. The multi item batch scheduling problem could be formulated into a biner-integer nonlinear programming model because the number of batch should be in integer value, the allocation of items to resulting batch need binary values, and also there are some non-linearity on objective function and constraint due to the dependent processing time. By applying relaxation on the decision variable of number of batch (N as parameter, a heuristic procedure could be applied to find solution of the single machine batch scheduling problem for multi items.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Comparison of CAT Item Selection Criteria for Polytomous Items

    Science.gov (United States)

    Choi, Seung W.; Swartz, Richard J.

    2009-01-01

    Item selection is a core component in computerized adaptive testing (CAT). Several studies have evaluated new and classical selection methods; however, the few that have applied such methods to the use of polytomous items have reported conflicting results. To clarify these discrepancies and further investigate selection method properties, six…

  16. Sex differences in guessing and item omission

    Directory of Open Access Journals (Sweden)

    Karolina Świst

    2015-09-01

    Full Text Available Guessing and item omission may be regarded as risk-taking or risk-avoidance strategies – sex specific adaptations to testing situations. In this article, these phenomena were analysed by (a percentage of omissions by sex, (b negative binomial regression to asses sex differences in the number of omissions, (c c-DIF analysis using IRT-LR test and (d linear regression using item attributes, to assess whether the c-parameter is sex differentiated by the percentage of omits (controlling item difficulty. The data set analysed were from the 2012–2014 Polish lower-secondary schools final exams, comprising tests in maths, language, science and humanities. Contrary to the vast body of literature, boys omitted items slightly more frequently than girls. Possible explanations of this finding – specific to the Polish examination system – were provided. The hypothesis of a higher c-parameter for boys did not find strong support from this study. It was shown that the c-parameter should not only be interpreted as resulting from item non-omission. This supports the modern concept of the c-parameter as a consequence not only of random guessing, but also problem solving, creative guessing or cheating.

  17. Determination of the caffeine contents of various food items within the Austrian market and validation of a caffeine assessment tool (CAT).

    Science.gov (United States)

    Rudolph, E; Färbinger, A; König, J

    2012-01-01

    The caffeine content of 124 products, including coffee, coffee-based beverages, energy drinks, tea, colas, yoghurt and chocolate, were determined using RP-HPLC with UV detection after solid-phase extraction. Highest concentrations of caffeine were found for coffee prepared from pads (755 mg l⁻¹) and regular filtered coffee (659 mg l⁻¹). The total caffeine content of coffee and chocolate-based beverages was between 15 mg l⁻¹ in chocolate milk and 448 mg l⁻¹ in canned ice coffee. For energy drinks the caffeine content varied in a range from 266 to 340 mg l⁻¹. Caffeine concentrations in tea and ice teas were between 13 and 183 mg l⁻¹. Coffee-flavoured yoghurts ranged from 33 to 48 mg kg⁻¹. The caffeine concentration in chocolate and chocolate bars was between 17 mg kg⁻¹ in whole milk chocolate and 551 mg kg⁻¹ in a chocolate with coffee filling. A caffeine assessment tool was developed and validated by a 3-day dietary record (r²= 0.817, p caffeine saliva concentrations (r²= 0.427, p < 0.01).

  18. Whole dairy matrix or single nutrients in assessment of health effects: current evidence and knowledge gaps.

    Science.gov (United States)

    Thorning, Tanja Kongerslev; Bertram, Hanne Christine; Bonjour, Jean-Philippe; de Groot, Lisette; Dupont, Didier; Feeney, Emma; Ipsen, Richard; Lecerf, Jean Michel; Mackie, Alan; McKinley, Michelle C; Michalski, Marie-Caroline; Rémond, Didier; Risérus, Ulf; Soedamah-Muthu, Sabita S; Tholstrup, Tine; Weaver, Connie; Astrup, Arne; Givens, Ian

    2017-05-01

    Foods consist of a large number of different nutrients that are contained in a complex structure. The nature of the food structure and the nutrients therein (i.e., the food matrix) will determine the nutrient digestion and absorption, thereby altering the overall nutritional properties of the food. Thus, the food matrix may exhibit a different relation with health indicators compared to single nutrients studied in isolation. The evidence for a dairy matrix effect was presented and discussed by an expert panel at a closed workshop, and the following consensus was reached: 1 ) Current evidence does not support a positive association between intake of dairy products and risk of cardiovascular disease (i.e., stroke and coronary heart disease) and type 2 diabetes. In contrast, fermented dairy products, such as cheese and yogurt, generally show inverse associations. 2 ) Intervention studies have indicated that the metabolic effects of whole dairy may be different than those of single dairy constituents when considering the effects on body weight, cardiometabolic disease risk, and bone health. 3 ) Different dairy products seem to be distinctly linked to health effects and disease risk markers. 4 ) Different dairy structures and common processing methods may enhance interactions between nutrients in the dairy matrix, which may modify the metabolic effects of dairy consumption. 5 ) In conclusion, the nutritional values of dairy products should not be considered equivalent to their nutrient contents but, rather, be considered on the basis of the biofunctionality of the nutrients within dairy food structures. 6 ) Further research on the health effects of whole dairy foods is warranted alongside the more traditional approach of studying the health effects of single nutrients. Future diet assessments and recommendations should carefully consider the evidence of the effects of whole foods alongside the evidence of the effects of individual nutrients. Current knowledge gaps and

  19. A New Kind of Single-Well Tracer Test for Assessing Subsurface Heterogeneity

    Science.gov (United States)

    Hansen, S. K.; Vesselinov, V. V.; Lu, Z.; Reimus, P. W.; Katzman, D.

    2017-12-01

    Single-well injection-withdrawal (SWIW) tracer tests have historically been interpreted using the idealized assumption of tracer path reversibility (i.e., negligible background flow), with background flow due to natural hydraulic gradient being an un-modeled confounding factor. However, we have recently discovered that it is possible to use background flow to our advantage to extract additional information about the subsurface. To wit: we have developed a new kind of single-well tracer test that exploits flow due to natural gradient to estimate the variance of the log hydraulic conductivity field of a heterogeneous aquifer. The test methodology involves injection under forced gradient and withdrawal under natural gradient, and makes use of a relationship, discovered using a large-scale Monte Carlo study and machine learning techniques, between power law breakthrough curve tail exponent and log-hydraulic conductivity variance. We will discuss how we performed the computational study and derived this relationship and then show an application example in which our new single-well tracer test interpretation scheme was applied to estimation of heterogeneity of a formation at the chromium contamination site at Los Alamos National Laboratory. Detailed core hole records exist at the same site, from which it was possible to estimate the log hydraulic conductivity variance using a Kozeny-Carman relation. The variances estimated using our new tracer test methodology and estimated by direct inspection of core were nearly identical, corroborating the new methodology. Assessment of aquifer heterogeneity is of critical importance to deployment of amendments associated with in-situ remediation strategies, since permeability contrasts potentially reduce the interaction between amendment and contaminant. Our new tracer test provides an easy way to obtain this information.

  20. Assessing arsenic and selenium in a single nail clipping using portable X-ray fluorescence

    International Nuclear Information System (INIS)

    Fleming, David E.B.; Nader, Michel N.; Foran, Kelly A.; Groskopf, Craig; Reno, Michael C.; Ware, Chris S.; Tehrani, Mina; Guimarães, Diana; Parsons, Patrick J.

    2017-01-01

    The feasibility of measuring arsenic and selenium contents in a single nail clipping was investigated using a small-focus portable X-ray fluorescence (XRF) instrument with monochromatic excitation beams. Nail clipping phantoms supplemented with arsenic and selenium to produce materials with 0, 5, 10, 15, and 20 µg/g were used for calibration purposes. In total, 10 different clippings were analyzed at two different measurement positions. Energy spectra were fit with detection peaks for arsenic K α , selenium K α , arsenic K β , selenium K β , and bromine K α characteristic X-rays. Data analysis was performed under two distinct conditions of fitting constraint. Calibration lines were established from the amplitude of each of the arsenic and selenium peaks as a function of the elemental contents in the clippings. The slopes of the four calibration lines were consistent between the two conditions of analysis. The calculated minimum detection limit (MDL) of the method, when considering the K α peak only, ranged from 0.210±0.002 µg/g selenium under one condition of analysis to 0.777±0.009 µg/g selenium under another. Compared with previous portable XRF nail clipping studies, MDLs were substantially improved for both arsenic and selenium. The new measurement technique had the additional benefits of being short in duration (~3 min) and requiring only a single nail clipping. The mass of the individual clipping used did not appear to play a major role in signal strength, but positioning of the clipping is important. - Highlights: • Portable X-ray fluorescence was used to assess As and Se in nail clipping phantoms. • Calibration lines were consistent between two different conditions of data analysis. • This new XRF approach was sensitive and required only a single nail clipping.

  1. Testing Three-Item Versions for Seven of Young's Maladaptive Schema

    Science.gov (United States)

    Blau, Gary; DiMino, John; Sheridan, Natalie; Pred, Robert S.; Beverly, Clyde; Chessler, Marcy

    2015-01-01

    The Young Schema Questionnaire (YSQ) in either long-form (205- item) or short-form (75-item or 90-item) versions has demonstrated its clinical usefulness for assessing early maladaptive schemas. However, even a 75 or 90-item "short form", particularly when combined with other measures, can represent a lengthy…

  2. Subjective and Objective Quality Assessment of Single-Channel Speech Separation Algorithms

    DEFF Research Database (Denmark)

    Mowlaee, Pejman; Saeidi, Rahim; Christensen, Mads Græsbøll

    2012-01-01

    Previous studies on performance evaluation of single-channel speech separation (SCSS) algorithms mostly focused on automatic speech recognition (ASR) accuracy as their performance measure. Assessing the separated signals by different metrics other than this has the benefit that the results...... are expected to carry on to other applications beyond ASR. In this paper, in addition to conventional speech quality metrics (PESQ and SNRloss), we also evaluate the separation systems output using different source separation metrics: blind source separation evaluation (BSS EVAL) and perceptual evaluation...... that PESQ and PEASS quality metrics predict well the subjective quality of separated signals obtained by the separation systems. From the results it is observed that the short-time objective intelligibility (STOI) measure predict the speech intelligibility results....

  3. Assessing the Performance of Two Bioinspired Algorithms to Solve Single-Row Layout Problem

    Directory of Open Access Journals (Sweden)

    Berna Haktanirlar Ulutas

    2013-01-01

    Full Text Available The single-row layout problem (SRLP, also known as the one-dimensional layout problem, deals with arranging a number of rectangular machines/departments with equal or varying dimensions on a straight line. Since the problem is proved to be NP-hard, there are several heuristics developed to solve the problem. This study introduces both a Clonal Selection Algorithm (CSA and a Bacterial Foraging Algorithm (BFA for SRLP. The performance of the algorithms is assessed by using three (small, medium, and large sized well known test problems available in the literature. The promising results illustrated that both algorithms had generated the best known solutions so far for most of the problems or provided better results for a number of problems.

  4. The PROMIS fatigue item bank has good measurement properties in patients with fibromyalgia and severe fatigue.

    Science.gov (United States)

    Yost, Kathleen J; Waller, Niels G; Lee, Minji K; Vincent, Ann

    2017-06-01

    Efficient management of fibromyalgia (FM) requires precise measurement of FM-specific symptoms. Our objective was to assess the measurement properties of the Patient-Reported Outcome Measurement Information System (PROMIS) fatigue item bank (FIB) in people with FM. We applied classical psychometric and item response theory methods to cross-sectional PROMIS-FIB data from two samples. Data on the clinical FM sample were obtained at a tertiary medical center. Data for the U.S. general population sample were obtained from the PROMIS network. The full 95-item bank was administered to both samples. We investigated dimensionality of the item bank in both samples by separately fitting a bifactor model with two group factors; experience and impact. We assessed measurement invariance between samples, and we explored an alternate factor structure with the normative sample and subsequently confirmed that structure in the clinical sample. Finally, we assessed whether reporting FM subdomain scores added value over reporting a single total score. The item bank was dominated by a general fatigue factor. The fit of the initial bifactor model and evidence of measurement invariance indicated that the same constructs were measured across the samples. An alternative bifactor model with three group factors demonstrated slightly improved fit. Subdomain scores add value over a total score. We demonstrated that the PROMIS-FIB is appropriate for measuring fatigue in clinical samples of FM patients. The construct can be presented by a single score; however, subdomain scores for the three group factors identified in the alternative model may also be reported.

  5. How best to teach developmental assessment? A single-blinded randomised study.

    Science.gov (United States)

    Feyereislova, Simona; Nathan, Dilip

    2014-12-01

    Developmental assessment is a core paediatric competency, but research demonstrates teaching gaps. This single-blinded, randomised controlled study compares three teaching approaches to developmental assessment in a large group setting based on a student's self-perception and objective competency assessment. Students were randomised into one of the following: ▸ a didactic lecture followed by self-study with online resources (control group), ▸ a didactic lecture and small group tutorial (small group) ▸ a combined didactic lecture and interactive component using audio-visual equipment (Interactive Developmental Teaching-IDT group). Competency scores (based on the Royal College of Paediatrics and Child Health (RCPCH) scoring system, adapted for undergraduates), mean scores of self-reported confidence and degree of motivation were compared between groups. 114 students participated. Statistically significant difference between mean assessment scores was demonstrated for the small group (38.0; 95% CI 36.5 to 39.6) and the IDT group (37.9; 95% CI 36.5 to 39.4) compared to the control group (34.8; 95% CI 33.2 to 36.4). Students' self-reported confidence, acquisition of knowledge and degree of motivation to practice was higher in IDT and small groups compared to the didactically taught control group. Teaching costs, if measured by trainer's time, were one-fifth in the IDT group compared to the small group teaching. The IDT is an effective teaching method in large groups, improves competencies compared to didactic lecturing, and is as effective as small group teaching. Adoption of the IDT appears to facilitate learning and can be easily delivered with falling ratios of teachers to students. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  6. Characterization of Disability in Canadians with Mental Disorders Using an Abbreviated Version of a DSM-5 Emerging Measure: The 12-Item WHO Disability Assessment Schedule (WHODAS) 2.0.

    Science.gov (United States)

    Sjonnesen, Kirsten; Bulloch, Andrew G M; Williams, Jeanne; Lavorato, Dina; B Patten, Scott

    2016-04-01

    The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) is a disability scale included in Section 3 of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as a possible replacement for the Global Assessment of Functioning Scale (GAF). To assist Canadian psychiatrists with interpretation of the scale, we have conducted a descriptive analysis using data from the 2012 Canadian Community Health Survey-Mental Health component (CCHS-MH). The 2012 CCHS-MH was a cross-sectional survey of the Canadian community (n = 23,757). The survey included an abbreviated 12-item version of the WHODAS 2.0. Mental disorder diagnoses were assessed for schizophrenia, other psychosis, major depressive episode (MDE), generalized anxiety disorder (GAD), bipolar I disorder, substance abuse/dependence, and alcohol abuse/dependence. Mean scores ranged from 14.2 (95% CI, 14.1 to 14.3) for the overall community population to 23.1 (95% CI, 19.5 to 26.7) for those with schizophrenia, with higher scores indicating greater disability. Furthermore, the difference in scores between those with lifetime and past-month episodes suggests that the scale is sensitive to changes occurring during the course of these disorders; for example, scores varied from 23.6 (95% CI, 22.2 to 25.1) for past-month MDE to 14.4 (95% CI, 14.2 to 14.7) in the lifetime MDE group without a past-year episode. This analysis suggests that the WHODAS 2.0 may be a suitable replacement for the GAF. As a disability measure, even though it is not a mental health-specific instrument, the 12-item WHODAS 2.0 appears to be sensitive to the impact of mental disorders and to changes over the time course of a mental disorder. However, the clinical utility of this measure requires additional assessment. © The Author(s) 2016.

  7. Computerized adaptive testing with item clones

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; van der Linden, Willem J.

    2001-01-01

    To reduce the cost of item writing and to enhance the flexibility of item presentation, items can be generated by item-cloning techniques. An important consequence of cloning is that it may cause variability on the item parameters. Therefore, a multilevel item response model is presented in which it

  8. Computerized adaptive testing with item cloning

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; van der Linden, Willem J.

    2003-01-01

    To increase the number of items available for adaptive testing and reduce the cost of item writing, the use of techniques of item cloning has been proposed. An important consequence of item cloning is possible variability between the item parameters. To deal with this variability, a multilevel item

  9. The Effects of Multiple-Step and Single-Step Directions on Fourth and Fifth Grade Students' Grammar Assessment Performance

    Science.gov (United States)

    Mazerik, Matthew B.

    2006-01-01

    The mean scores of English Language Learners (ELL) and English Only (EO) students in 4th and 5th grade (N = 110), across the teacher-administered Grammar Skills Test, were examined for differences in participants' scores on assessments containing single-step directions and assessments containing multiple-step directions. The results indicated no…

  10. Spatial assessment of wolf-dog hybridization in a single breeding period.

    Science.gov (United States)

    Pacheco, C; López-Bao, J V; García, E J; Lema, F J; Llaneza, L; Palacios, V; Godinho, R

    2017-02-14

    Understanding the dynamics of wolf-dog hybridization and delineating evidence-based conservation strategies requires information on the spatial extent of wolf-dog hybridization in real-time, which remains largely unknown. We collected 332 wolf-like scats over ca. 5,000km 2 in the NW Iberian Peninsula to evaluate wolf-dog hybridization at population level in a single breeding/pup-rearing season. Mitochondrial DNA (MtDNA) and 18 ancestry informative markers were used for species and individual identification, and to detect wolf-dog hybrids. Genetic relatedness was assessed between hybrids and wolves. We identified 130 genotypes, including 67 wolves and 7 hybrids. Three of the hybrids were backcrosses to dog whereas the others were backcrosses to wolf, the latter accounting for a 5.6% rate of introgression into the wolf population. Our results show a previously undocumented scenario of multiple and widespread wolf-dog hybridization events at the population level. However, there is a clear maintenance of wolf genetic identity, as evidenced by the sharp genetic identification of pure individuals, suggesting the resilience of wolf populations to a small amount of hybridization. We consider that real-time population level assessments of hybridization provide a new perspective into the debate on wolf conservation, with particular focus on current management guidelines applied in wolf-dog hybridization events.

  11. Spatial assessment of wolf-dog hybridization in a single breeding period

    Science.gov (United States)

    Pacheco, C.; López-Bao, J. V.; García, E. J.; Lema, F. J.; Llaneza, L.; Palacios, V.; Godinho, R.

    2017-01-01

    Understanding the dynamics of wolf-dog hybridization and delineating evidence-based conservation strategies requires information on the spatial extent of wolf-dog hybridization in real-time, which remains largely unknown. We collected 332 wolf-like scats over ca. 5,000km2 in the NW Iberian Peninsula to evaluate wolf-dog hybridization at population level in a single breeding/pup-rearing season. Mitochondrial DNA (MtDNA) and 18 ancestry informative markers were used for species and individual identification, and to detect wolf-dog hybrids. Genetic relatedness was assessed between hybrids and wolves. We identified 130 genotypes, including 67 wolves and 7 hybrids. Three of the hybrids were backcrosses to dog whereas the others were backcrosses to wolf, the latter accounting for a 5.6% rate of introgression into the wolf population. Our results show a previously undocumented scenario of multiple and widespread wolf-dog hybridization events at the population level. However, there is a clear maintenance of wolf genetic identity, as evidenced by the sharp genetic identification of pure individuals, suggesting the resilience of wolf populations to a small amount of hybridization. We consider that real-time population level assessments of hybridization provide a new perspective into the debate on wolf conservation, with particular focus on current management guidelines applied in wolf-dog hybridization events. PMID:28195213

  12. Assessment of high-rate GPS using a single-axis shake table

    Science.gov (United States)

    Häberling, S.; Rothacher, M.; Geiger, A.

    2012-04-01

    The latest generation of GPS receivers is capable of tracking at 100 Hz potentially capturing high-frequency signals. The new possibility to measure highly dynamic motions could enlarge the applicability in navigation and Earth monitoring such as seismology. In this study, we assess the potential of high-rate GPS with a sampling rate up to 100 Hz for a large spectrum of different motions. These motions are generated on a single-axis shake table carrying a GPS antenna. The real motion of the shake table is additionally monitored by highly accurate inductive sensors recording at 2400 Hz which deliver the ground-truth for the GPS assessment. In order to identify and quantify the internal GPS receiver errors as well as the external error sources, test experiments are carried out with zero-baselines, very short and long baselines. Our experiment setup allows a detailed study of the dynamic behaviour of the GPS receiver signal tracking for different accelerations. The investigations are focusing on the impact of different tracking loop parameters for L1 and L2 on the GPS results. In order to minimize the receiver errors during highly dynamic motions, an optimal set of tracking loop parameters and a good understanding of the receiver transfer function are crucial. The characteristics of the results are also compared with tests carried out in static mode and using different receiver types.

  13. Assessment of continuum mechanics models in predicting buckling strains of single-walled carbon nanotubes.

    Science.gov (United States)

    Zhang, Y Y; Wang, C M; Duan, W H; Xiang, Y; Zong, Z

    2009-09-30

    This paper presents an assessment of continuum mechanics (beam and cylindrical shell) models in the prediction of critical buckling strains of axially loaded single-walled carbon nanotubes (SWCNTs). Molecular dynamics (MD) simulation results for SWCNTs with various aspect (length-to-diameter) ratios and diameters will be used as the reference solutions for this assessment exercise. From MD simulations, two distinct buckling modes are observed, i.e. the shell-type buckling mode, when the aspect ratios are small, and the beam-type mode, when the aspect ratios are large. For moderate aspect ratios, the SWCNTs buckle in a mixed beam-shell mode. Therefore one chooses either the beam or the shell model depending on the aspect ratio of the carbon nanotubes (CNTs). It will be shown herein that for SWCNTs with long aspect ratios, the local Euler beam results are comparable to MD simulation results carried out at room temperature. However, when the SWCNTs have moderate aspect ratios, it is necessary to use the more refined nonlocal beam theory or the Timoshenko beam model for a better prediction of the critical strain. For short SWCNTs with large diameters, the nonlocal shell model with the appropriate small length scale parameter can provide critical strains that are in good agreement with MD results. However, for short SWCNTs with small diameters, more work has to be done to refine the nonlocal cylindrical shell model for better prediction of critical strains.

  14. Weighting of items in a tutorial performance evaluation instrument ...

    African Journals Online (AJOL)

    Weighting of items in an evaluation instrument contributes to more meaningful and valid interpretations of student performance in respect of each learning outcome or item being assessed. It follows that the validity of instruments is important for meaningful inferences about students' learning performance, including their ...

  15. Modifying measures based on differential item functioning (DIF) impact analyses.

    Science.gov (United States)

    Teresi, Jeanne A; Ramirez, Mildred; Jones, Richard N; Choi, Seung; Crane, Paul K

    2012-09-01

    Measure modification can impact comparability of scores across groups and settings. Changes in items can affect the percent admitting to a symptom. Using item response theory (IRT) methods, well-calibrated items can be used interchangeably, and the exact same item does not have to be administered to each respondent, theoretically permitting wider latitude in terms of modification. Recommendations regarding modifications vary, depending on the use of the measure. In the context of research, adjustments can be made at the analytic level by freeing and fixing parameters based on findings of differential item functioning (DIF). The consequences of DIF for clinical decision making depend on whether or not the patient's performance level approaches the scale decision cutpoint. High-stakes testing may require item removal or separate calibrations to ensure accurate assessment. Guidelines for modification based on DIF analyses and illustrations of the impact of adjustments are presented.

  16. A new approach to assessing intra-subject variability in single-subject designs

    Directory of Open Access Journals (Sweden)

    Katy Borodkin

    2014-04-01

    Full Text Available Research Aim: One of the methodological challenges of single-subject designs is accounting for intra-individual variability in performance, which is commonly assessed by applying the same testing materials on multiple sessions (McReynolds & Thompson, 1986. This approach might be less feasible in some individuals, such as bilingual speakers with aphasia, who would need to be tested, using the same materials, on several occasions within as well as across languages. Repetitive exposure to the same testing materials can increase practice effects and further reduce the validity of the testing. In the present study, we explored an alternative approach to measuring stability in performance by comparing the use of identical vs. different (but comparable testing materials. Method: Participants were five monolinguals with non-fluent aphasia following a single left CVA. Participants performed an action-naming task and two narrative tasks: a picture sequence and a personal narrative. There were two testing times, several weeks apart using identical materials. Each testing time included three consecutive sessions, using different materials. Action-naming performance was assessed by the number of correct verbs produced. The verbal output in the narrative tasks was scored for amount (number of utterances, grammaticality (percentage of grammatical sentences, and verb diversity (number of different verbs. Pearson correlation coefficients (r were computed to establish the intra-subject variability across testing times and across sessions. The magnitude of the correlations was evaluated using published guidelines (Strauss, Sherman, & Spreen, 2006. Results: For action naming, the correlations ranged from high to very high (.87 to .98 across testing times and from adequate to very high across sessions (.74 to .96. For the narrative tasks, the correlations between the number of utterances across testing times ranged from adequate to very high (.76 to .97 and from low

  17. Quantitative Assessment of Single-Image Super-Resolution in Myocardial Scar Imaging.

    Science.gov (United States)

    Ashikaga, Hiroshi; Estner, Heidi L; Herzka, Daniel A; Mcveigh, Elliot R; Halperin, Henry R

    Single-image super resolution is a process of obtaining a high-resolution image from a set of low-resolution observations by signal processing. While super resolution has been demonstrated to improve image quality in scaled down images in the image domain, its effects on the Fourier-based image acquisition technique, such as MRI, remains unknown.We performed high-resolution ex vivo late gadolinium enhancement (LGE) magnetic resonance imaging (0.4 × 0.4 × 0.4 mm 3 ) in postinfarction swine hearts ( n = 24). The swine hearts were divided into the training set ( n = 14) and the test set ( n = 10), and in all hearts, low-resolution images were simulated from the high-resolution images. In the training set, super-resolution dictionaries with pairs of small matching patches of the high- and low-resolution images were created. In the test set, super resolution recovered high-resolution images from low-resolution images using the dictionaries. The same algorithm was also applied to patient LGE ( n = 4) to assess its effects. Compared with interpolated images, super resolution significantly improved basic image quality indices ( P Super resolution using Fourier-based zero padding achieved the best image quality. However, the magnitude of improvement was small in images with zero padding. Super resolution substantially improved the spatial resolution of the patient LGE images by sharpening the edges of the heart and the scar. In conclusion, single-image super resolution significantly improves image errors. However, the magnitude of improvement was relatively small in images with Fourier-based zero padding. These findings provide evidence to support its potential use in myocardial scar imaging.

  18. Information weighted sampling for detecting rare items in finite populations with a focus on security

    NARCIS (Netherlands)

    Hoogstrate, A.J.; Klaassen, C.A.J.

    2015-01-01

    Frequently one has to search within a finite population for a single particular individual or item with a rare characteristic. Whether an item possesses the characteristic can only be determined by close inspection. The availability of additional information about the items in the population opens

  19. Retrieval of very large numbers of items in the Web of Science: an exercise to develop accurate search strategies

    NARCIS (Netherlands)

    Arencibia-Jorge, R.; Leydesdorff, L.; Chinchilla-Rodríguez, Z.; Rousseau, R.; Paris, S.W.

    2009-01-01

    The Web of Science interface counts at most 100,000 retrieved items from a single query. If the query results in a dataset containing more than 100,000 items the number of retrieved items is indicated as >100,000. The problem studied here is how to find the exact number of items in a query that

  20. RELIABILITY OF KINEMATICS AND KINETICS ASSOCIATED WITH HORIZONTAL SINGLE LEG DROP JUMP ASSESSMENT. A BRIEF REPORT

    Directory of Open Access Journals (Sweden)

    Markus Stålbom

    2007-06-01

    Full Text Available Determining the reliability of a unilateral horizontal drop jump for displacement provided the focus for this research. Eighteen male subjects were required to step off a 20cm box and land on a force plate with one leg and thereafter jump for maximal horizontal displacement on two different days. Dependent variables from the jump assessment included mean and peak vertical (V and horizontal (H ground reaction forces (GRF and impulses, horizontal displacement and contact time. The between-trial variability of all kinematic and kinetic measures was less than 7%. The most consistent measure over both trials was the horizontal displacement jumped (1.2 to 1.4% and the most variable were the contact time the first day (6.5% and peak HGRF the second day (4.3%. In all cases there was less variation associated with the second rather than the first day. In terms of test-retest variability the percent changes in the means and coefficient of variations (CVs were all under 10%. The smallest changes in the mean (0.43 %, least variation (< 2.26 % and second highest intraclass correlation co-efficient (ICC = 0.95 were found for horizontal displacement jumped. The highest ICC (0.96 was found for horizontal impulse. Given the reliability of the single leg drop jump, it may offer better prognostic and diagnostic information than that obtained with bilateral vertical jumps

  1. Single-case experimental designs to assess intervention effectiveness in rehabilitation: A practical guide.

    Science.gov (United States)

    Krasny-Pacini, Agata; Evans, Jonathan

    2017-12-15

    Single-case experimental designs (SCED) are experimental designs aiming at testing the effect of an intervention using a small number of patients (typically one to three), using repeated measurements, sequential (±randomized) introduction of an intervention and method-specific data analysis, including visual analysis and specific statistics. The aim of this paper is to familiarise professionals working in different fields of rehabilitation with SCEDs and provide practical advice on how to design and implement a SCED in clinical rehabilitation practice. Research questions suitable for SCEDs and the different types of SCEDs (e.g., alternating treatment designs, introduction/withdrawal designs and multiple baseline designs) are reviewed. Practical steps in preparing a SCED design are outlined. Examples from different rehabilitation domains are provided throughout the paper. Challenging issues such as the choice of the repeated measure, assessment of generalisation, randomization, procedural fidelity, replication and generalizability of findings are discussed. Simple rules and resources for data analysis are presented. The utility of SCEDs in physical and rehabilitation medicine (PRM) are discussed. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  2. Assessing Motor Fluctuations in Parkinson's Disease Patients Based on a Single Inertial Sensor.

    Science.gov (United States)

    Pérez-López, Carlos; Samà, Albert; Rodríguez-Martín, Daniel; Català, Andreu; Cabestany, Joan; Moreno-Arostegui, Juan Manuel; de Mingo, Eva; Rodríguez-Molinero, Alejandro

    2016-12-15

    Altered movement control is typically the first noticeable symptom manifested by Parkinson's disease (PD) patients. Once under treatment, the effect of the medication is very patent and patients often recover correct movement control over several hours. Nonetheless, as the disease advances, patients present motor complications. Obtaining precise information on the long-term evolution of these motor complications and their short-term fluctuations is crucial to provide optimal therapy to PD patients and to properly measure the outcome of clinical trials. This paper presents an algorithm based on the accelerometer signals provided by a waist sensor that has been validated in the automatic assessment of patient's motor fluctuations (ON and OFF motor states) during their activities of daily living. A total of 15 patients have participated in the experiments in ambulatory conditions during 1 to 3 days. The state recognised by the algorithm and the motor state annotated by patients in standard diaries are contrasted. Results show that the average specificity and sensitivity are higher than 90%, while their values are higher than 80% of all patients, thereby showing that PD motor status is able to be monitored through a single sensor during daily life of patients in a precise and objective way.

  3. Recent advances in magnesium assessment: From single selective sensors to multisensory approach.

    Science.gov (United States)

    Lvova, Larisa; Gonçalves, Carla Guanais; Di Natale, Corrado; Legin, Andrey; Kirsanov, Dmitry; Paolesse, Roberto

    2018-03-01

    The development of efficient analytical procedures for the selective detection of magnesium is an important analytical task, since this element is one of the most abundant metals in cells and plays an essential role in a plenty of cellular processes. Magnesium misbalance has been related to several pathologies and diseases both in plants and animals, as far as in humans, but the number of suitable methods for magnesium detection especially in life sample and biological environments is scarce. Chemical sensors, due to their high reliability, simplicity of handling and instrumentation, fast and real-time in situ and on site analysis are promising candidates for magnesium analysis and represent an attractive alternative to the standard instrumental methods. Here the recent achievements in the development of chemical sensors for magnesium ions detection over the last decade are reviewed. The working principles and the main types of sensors applied are described. Focus is placed on the optical sensors and multisensory systems applications for magnesium assessment in different media. Further, a critical outlook on the employment of multisensory approach in comparison to single selective sensors application in biological samples is presented. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Online Angiography Image-Based FFR Assessment During Coronary Catheterization: A Single-Center Study.

    Science.gov (United States)

    Kornowski, Ran; Vaknin-Assa, Hana; Assali, Abid; Greenberg, Gabriel; Valtzer, Orna; Lavi, Ifat

    2018-03-15

    To assess the diagnostic performance of angiography-derived fractional flow reserve (FFRangio) measurements in patients with stable coronary artery disease when used online in the catheterization laboratory during routine coronary angiography. FFR, an index of the hemodynamic severity of coronary stenosis, is derived from invasive measurements using a pressure-monitoring guidewire and hyperemic stimulus. While FFR is the gold standard, it remains under-utilized. FFRangio may have several advantages owing to the reduced operator time, no wire-related or procedural complications, and no need for administration of vasodilators. FFRangio is a novel technology that uses a patient's hemodynamic data and routine angiograms to generate FFR values at each point along the coronary tree. We present the online application of the system where FFRangio was successfully used in the catheterization laboratory during routine coronary angiography and compared to invasive FFR. Fifty-three patients (79% men) and 60 coronary lesions were analyzed. Values derived using FFRangio ranged from 0.58-0.96 and correlated closely (Pearson's correlation coefficient, r=0.91; Psystem. In this single-center experience, FFRangio values showed high correlation rates to invasive FFR.

  5. Dimensionality of the UWES-17: An item response modelling analysis

    Directory of Open Access Journals (Sweden)

    Deon P. de Bruin

    2013-10-01

    Research purpose: The main focus of this study was to use the Rasch model to provide insight into the dimensionality of the UWES-17, and to assess whether work engagement should be interpreted as one single overall score, three separate scores, or a combination. Motivation for the study: It is unclear whether a summative score is more representative of work engagement or whether scores are more meaningful when interpreted for each dimension separately. Previous work relied on confirmatory factor analysis; the potential of item response models has not been tapped. Research design: A quantitative cross-sectional survey design approach was used. Participants, 2429 employees of a South African Information and Communication Technology (ICT company, completed the UWES-17. Main findings: Findings indicate that work engagement should be treated as a unidimensional construct: individual scores should be interpreted in a summative manner, giving a single global score. Practical/managerial implications: Users of the UWES-17 may interpret a single, summative score for work engagement. Findings of this study should also contribute towards standardising UWES-17 scores, allowing meaningful comparisons to be made. Contribution/value-add: The findings will benefit researchers, organisational consultants and managers. Clarity on dimensionality and interpretation of work engagement will assist researchers in future studies. Managers and consultants will be able to make better-informed decisions when using work engagement data.

  6. Single screening questions for cognitive impairment in older people: a systematic review.

    Science.gov (United States)

    Hendry, Kirsty; Hill, Eilidh; Quinn, Terry J; Evans, Jonathan; Stott, David J

    2015-03-01

    Single-item screening questions may be a practical first step in screening for cognitive problems in older people. A form of single-item cognitive assessment is proposed in the NHS England and Wales dementia strategy. We aimed to provide a review and synthesis of the evidence regarding the performance of single-item tests for detection of cognitive impairment. This review used Cochrane diagnostic test accuracy procedures. Two independent researchers searched for relevant papers across multiple, cross-disciplinary electronic databases using previously validated search strings. Our index test was any single screening question for cognitive impairment, including factor analysis of multi-item tools. Our reference standards included clinical diagnosis and multi-domain cognitive assessments. From 884 titles, 11 studies were identified as eligible for inclusion. Four studies were graded low risk of bias and recruited a representative patient sample. Five papers described a single screening question for cognitive impairment with each using a different question. Sensitivity ranged from 26 to 96% and specificity from 45 to 100%. Six papers described the component analysis of multiple item tools with broadly worded single questions ('decline in memory function', 'changes in ability to think and reason' or 'learning new things') performing best. Informant-based, single-item screening questions show promise for detecting cognitive impairment. However, there was substantial heterogeneity in format and application of single-item screens, and several studies were of poor methodological quality. Currently, there is insufficient evidence to support routine screening using a single-item approach. © The Author 2014. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

    Science.gov (United States)

    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

  8. Using a Process Dissociation Approach to Assess Verbal Short-Term Memory for Item and Order Information in a Sample of Individuals with a Self-Reported Diagnosis of Dyslexia.

    Science.gov (United States)

    Wang, Xiaoli; Xuan, Yifu; Jarrold, Christopher

    2016-01-01

    Previous studies have examined whether difficulties in short-term memory for verbal information, that might be associated with dyslexia, are driven by problems in retaining either information about to-be-remembered items or the order in which these items were presented. However, such studies have not used process-pure measures of short-term memory for item or order information. In this work we adapt a process dissociation procedure to properly distinguish the contributions of item and order processes to verbal short-term memory in a group of 28 adults with a self-reported diagnosis of dyslexia and a comparison sample of 29 adults without a dyslexia diagnosis. In contrast to previous work that has suggested that individuals with dyslexia experience item deficits resulting from inefficient phonological representation and language-independent order memory deficits, the results showed no evidence of specific problems in short-term retention of either item or order information among the individuals with a self-reported diagnosis of dyslexia, despite this group showing expected difficulties on separate measures of word and non-word reading. However, there was some suggestive evidence of a link between order memory for verbal material and individual differences in non-word reading, consistent with other claims for a role of order memory in phonologically mediated reading. The data from the current study therefore provide empirical evidence to question the extent to which item and order short-term memory are necessarily impaired in dyslexia.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Effects of age on negative subsequent memory effects associated with the encoding of item and item-context information.

    Science.gov (United States)

    Mattson, Julia T; Wang, Tracy H; de Chastelaine, Marianne; Rugg, Michael D

    2014-12-01

    It has consistently been reported that "negative" subsequent memory effects--lower study activity for later remembered than later forgotten items--are attenuated in older individuals. The present functional magnetic resonance imaging study investigated whether these findings extend to subsequent memory effects associated with successful encoding of item-context information. Older (n = 25) and young (n = 17) subjects were scanned while making 1 of 2 encoding judgments on a series of pictures. Memory was assessed for the study item and, for items judged old, the item's encoding task. Both memory judgments were made using confidence ratings, permitting item and source memory strength to be unconfounded and source confidence to be equated across age groups. Replicating prior findings, negative item effects in regions of the default mode network in young subjects were reversed in older subjects. Negative source effects, however, were invariant with respect to age and, in both age groups, the magnitude of the effects correlated with source memory performance. It is concluded that negative item effects do not reflect processes necessary for the successful encoding of item-context associations in older subjects. Negative source effects, in contrast, appear to reflect the engagement of processes that are equally important for successful episodic encoding in older and younger individuals. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Single nucleotide polymorphisms for assessing genetic diversity in castor bean (Ricinus communis

    Directory of Open Access Journals (Sweden)

    Rabinowicz Pablo D

    2010-01-01

    Full Text Available Abstract Background Castor bean (Ricinus communis is an agricultural crop and garden ornamental that is widely cultivated and has been introduced worldwide. Understanding population structure and the distribution of castor bean cultivars has been challenging because of limited genetic variability. We analyzed the population genetics of R. communis in a worldwide collection of plants from germplasm and from naturalized populations in Florida, U.S. To assess genetic diversity we conducted survey sequencing of the genomes of seven diverse cultivars and compared the data to a reference genome assembly of a widespread cultivar (Hale. We determined the population genetic structure of 676 samples using single nucleotide polymorphisms (SNPs at 48 loci. Results Bayesian clustering indicated five main groups worldwide and a repeated pattern of mixed genotypes in most countries. High levels of population differentiation occurred between most populations but this structure was not geographically based. Most molecular variance occurred within populations (74% followed by 22% among populations, and 4% among continents. Samples from naturalized populations in Florida indicated significant population structuring consistent with local demes. There was significant population differentiation for 56 of 78 comparisons in Florida (pairwise population ϕPT values, p Conclusion Low levels of genetic diversity and mixing of genotypes have led to minimal geographic structuring of castor bean populations worldwide. Relatively few lineages occur and these are widely distributed. Our approach of determining population genetic structure using SNPs from genome-wide comparisons constitutes a framework for high-throughput analyses of genetic diversity in plants, particularly in species with limited genetic diversity.

  12. Telemetric assessment of social and single housing: Evaluation of electrocardiographic intervals in jacketed cynomolgus monkeys.

    Science.gov (United States)

    Kaiser, Robert A; Tichenor, Stephen D; Regalia, Douglas E; York, Kristina; Holzgrefe, Henry H

    2015-01-01

    Proactive efforts to socially house laboratory animals are a contemporary, important focus for enhancing animal welfare. Jacketing cynomolgus monkeys has been traditionally considered an exclusionary criterion for social housing based on unsubstantiated concerns that study conduct or telemetry equipment might be compromised. Our objective was to evaluate the effects of jacketing naïve, adolescent cynomolgus monkeys in different single and social housing types based on parallel comparisons of heart rate. Eight naive cynomolgus monkeys were randomized into pairs and ECG data were collected for 24h from each animal in each housing condition using a crossover design. Caging paradigms consisted of standard individual, standard pair, quaternary pair (4 linked cages), and European-style pair housing in non-sequential order varied by pair to control for possible time bias. Dosing and blood collection procedures were performed to characterize any effects of housing on ECG data during study conduct. There was no increase in the incidence of equipment damage in pair vs. individually housed animals. Further, animals in all 4 housing paradigms showed similar acclimation assessed as heart rate (mean 139-154 beats per minute), and maintained similar diurnal rhythms, with an expected slowing of the heart rate at night (aggregate lights out HR 110±4bpm compared to daytime 146±7bpm). This study demonstrates the effects of different social access and housing types on the study-naïve cynomolgus monkeys during jacketed cardiovascular telemetry data collection in a repeat-dose toxicology study design. There were no discernible effects of social housing on baseline ECG parameters collected via jacketed telemetry, and all animals maintained expected diurnal rhythms in all housing settings tested. These data demonstrate that cynomolgus monkeys can be socially housed during data collection as a standard practice, consistent with global efforts to improve study animal welfare. Copyright

  13. 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...

  14. Optimal sampling strategies to assess inulin clearance in children by the inulin single-injection method

    NARCIS (Netherlands)

    van Rossum, Lyonne K.; Mathot, Ron A. A.; Cransberg, Karlien; Vulto, Arnold G.

    2003-01-01

    Glomerular filtration rate in patients can be determined by estimating the plasma clearance of inulin with the single-injection method. In this method, a single bolus injection of inulin is administered and several blood samples are collected. For practical and convenient application of this method

  15. Design of a box trainer for objective assessment of technical skills in single-port surgery

    NARCIS (Netherlands)

    Horeman, Tim; Sun, Siyu; Tuijthof, Gabrielle J. M.; Jansen, Frank William; Meijerink, Jeroen W. J. H. J.; Dankelman, Jenny

    2015-01-01

    Laparoscopic single-port (SP) surgery uses only a single entry point for all instruments. The approach of SP has been applied in multiple laparoscopic disciplines owing to its improved cosmetic result. However, in SP surgery, instrument movements are further restricted, resulting in increased

  16. Assessment of changes in regional cerebral blood flow in patients with major depression using the 99mTc-HMPAO single photon emission tomography method

    International Nuclear Information System (INIS)

    Yazici, K.; Kapucu, Oe.; Erbas, B.; Varoglu, E.; Guelec, C.; Bekdik, C.F.; Hacettepe Univ., Ankara

    1992-01-01

    Regional cerebral blood flow was investigated in 14 patients with major depression diagnosed according to the DSM-III-R criteria (six patients with single and eight patients with recurrent episodes) and in ten healthy volunteers. The mean ages of the patients and the controls were 33.5±2.7 and 31.6±2.6 years, respectively. The severity of the depression was assessed using the 17-item Hamiltonian Depression Scale (mean: 23.2±1.5). None of the patients was under medication. After administration of 500 MBq technetium-99m hexamethylpropylene amine oxime, a single photon emission tomography study was performed and then transaxial, sagittal and coronal slices were obtained. For the semiquantitative analysis of the data, the ratios of the mean counts/pixel to the whole slice were calculated for 24 regions on three consecutive transaxial slices in the orbitomeatal plane. Additionally, left/right and frontal/occipital ratios were calculated. Both sides of the temporal region had a significantly decreased cerebral blood flow (CBF) when compared to the controls. The left/right ratio of the prefrontal region was also significantly lower in the patients than in the controls. The Hamilton score had a negative correlation with blood flow in the anterofrontal and left prefrontal regions. According to our results, regional CBF seems to be decreased in the left prefrontal and in both temporal regions in major depression. The severity of depression is correlated with the reduction in CBF in the regions of the anterofrontal and left prefrontal cortex. (orig.)

  17. Assessment of endogenous dopamine release by methylphenidate challenge using iodine-123 iodobenzamide single-photon emission tomography

    NARCIS (Netherlands)

    Booij, J.; Korn, P.; Linszen, D. H.; van Royen, E. A.

    1997-01-01

    This double-blind, placebo-controlled study assessed pharmacologically induced endogenous dopamine (DA) release in healthy male volunteers (n=12). Changes in endogenous DA release after injection of the psychostimulant drug methylphenidate were evaluated by single-photon emission tomography (SPET)

  18. Influence of nail varnish on the remineralization of enamel single sections assessed by microradiography and confocal laser scanning microscopy

    NARCIS (Netherlands)

    Iijima, Y; Takagi, O; Duschner, H; Ruben, J; Arends, J

    1998-01-01

    Single-section techniques are attractive in enamel de- and remineralization investigations because they allow longitudinal studies in which mineral changes can be assessed by microradiography (TMR), Nail Varnish (NV) is in general applied to coat the cut thin-section sides, The aims of this study

  19. Brief Sensation Seeking Scale: Latent structure of 8-item and 4-item versions in Peruvian adolescents.

    Science.gov (United States)

    Merino-Soto, Cesar; Salas Blas, Edwin

    2018-01-01

    This research intended to validate two brief scales of sensations seeking with Peruvian adolescents: the eight item scale (BSSS8; Hoyle, Stephenson, Palmgreen, Lorch, y Donohew, 2002) and the four item scale (BSSS4; Stephenson, Hoyle, Slater, y Palmgreen, 2003). Questionnaires were administered to 618 voluntary participants, with an average age of 13.6 years, from different levels of high school, state and private school in a district in the south of Lima. It analyzed the internal structure of both short versions using three models: a) unidimensional (M1), b) oblique or related dimensions (M2), and c) the bifactor model (M3). Results show that both instruments have a single dimension which best represents the variability of the items; a fact that can be explained both by the complexity of the concept and by the small number of items representing each factor, which is more noticeable in the BSSS4. Reliability is within levels found by previous studies: alpha: .745 = BSSS8 and BSSS4 =. 643; omega coefficient: .747 in BSSS8 and .651 in BSSS4. These are considered suitable for the type of instruments studied. Based on the correlation between the two instruments, it was found that there are satisfactory levels of equivalence between the BSSS8 and BSSS4. However, it is recommended that the BSSS4 is mainly used for research and for the purpose of describing populations.

  20. Identifying predictors of physics item difficulty: A linear regression approach

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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).

  2. Weighting and Aggregation in Life Cycle Assessment: Do Present Aggregated Single Scores Provide Correct Decision Support?

    DEFF Research Database (Denmark)

    Kalbar, Pradip; Birkved, Morten; Nygaard, Simon Elsborg

    2016-01-01

    approach was adopted to facilitate identification of three main problems related to the single-score calculation approach. The prevailing ReCiPe single-score calculation method does not account for either the effect of so-called dominating alternatives (i.e., alternatives having high values across all...... endpoints) or the interdependency of the indicators being aggregated. It was also found that the simple linear weighted sum method, presently used for obtaining single scores, is not capable of accounting for the effect of weighting schemes and thus cannot realistically represent stakeholders' perspectives...

  3. Colorado Student Assessment Program: 2001 Released Passages, Items, and Prompts. Grade 4 Reading and Writing, Grade 4 Lectura y Escritura, Grade 5 Mathematics and Reading, Grade 6 Reading, Grade 7 Reading and Writing, Grade 8 Mathematics, Reading and Science, Grade 9 Reading, and Grade 10 Mathematics and Reading and Writing.

    Science.gov (United States)

    Colorado State Dept. of Education, Denver.

    This document contains released reading comprehension passages, test items, and writing prompts from the Colorado Student Assessment Program for 2001. The sample questions and prompts are included without answers or examples of student responses. Test materials are included for: (1) Grade 4 Reading and Writing; (2) Grade 4 Lectura y Escritura…

  4. Creating New Items in Zotero

    Directory of Open Access Journals (Sweden)

    Amanda Morton

    2013-04-01

    Full Text Available In Intro to the Zotero API, you learned a little bit about Zotero; now you can access some of its functions using Python scripts. In this lesson, you will create a new item in a Zotero library and add some basic metadata such as title and date.

  5. Differential item functioning (DIF) of SF-12 and Q-LES-Q-SF items among french substance users.

    Science.gov (United States)

    Bourion-Bédès, Stéphanie; Schwan, Raymund; Laprevote, Vincent; Bédès, Alex; Bonnet, Jean-Louis; Baumann, Cédric

    2015-10-24

    Differential Item Functioning (DIF) is investigated to ensure that each item displays a consistent pattern of responses irrespective of the characteristics of the respondents. Assessing DIF helps to understand the nature of instruments, to assess the quality of a measure and to interpret results. This study aimed to examine whether the items of the Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form (Q-LES-Q-SF) and Short-Form 12 (SF-12) exhibit DIF. A total of 124 outpatients diagnosed with substance dependence participated in a cross-sectional, multicenter study. In addition to the Q-LES-Q-SF and SF-12 results, demographic data such as age, sex, type of substance dependence and education level were collected. Rasch analysis was conducted (using RUMM2020 software) to assess DIF of the Q-LES-Q-SF and SF-12 items. For SF-12, significant age-related uniform DIF was found in two of the 12 items, and sex-related DIF was found in one of the 12 items. All of the observed DIF effects in SF-12 were found among the mental health items. Three items showed DIF on the Q-LES-Q-SF; however, the impact of DIF item on the delta score calculation for the comparisons of self-reported health status between the groups was minimal in the SF-12 and small in the Q-LES-Q-SF. These results indicated that no major measurement bias affects the validity of the self-reported health status assessed using the Q-LES-Q-SF or SF-12. Thus, these questionnaires are largely robust measures of self-reported health status among substance users.

  6. Development of Cost-Effective Screening Techniques to Assess Single-Event Latchup Susceptibility

    Data.gov (United States)

    National Aeronautics and Space Administration — Although Single-Event Latchup (SEL) has proven to be one of the most significant radiation threats for low-cost missions, conventional SEL hardness assurance...

  7. Alternative approaches to updating item parameter estimates in tests with item cloning

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    2006-01-01

    Item cloning techniques can greatly reduce the cost of item writing and enhance the flexibility of item presentation. To deal with the possible variability of the item parameters caused by item cloning, Glas and van der Linden (in press, 2006) proposed a multilevel item response model where it is

  8. Administration of follitropin alfa and lutropin alfa combined in a single injection: a feasibility assessment

    Directory of Open Access Journals (Sweden)

    Agostinetto Rita

    2009-05-01

    Full Text Available Abstract Background Gonadotrophins are routinely administered in assisted reproductive technology (ART treatment protocols. Recombinant human follicle-stimulating hormone (r-hFSH; follitropin alfa and recombinant human luteinizing hormone (r-hLH; lutropin alfa can be administered individually or in a fixed combination. The ability to vary the FSH to LH dose ratio in a single injection without compromising the bioactivity of either gonadotrophin or generating losses of active principle is important for physicians and patients alike. Methods This study investigated whether follitropin alfa (GONAL-f (R, as lyophilized powder for reconstitution or solution from the GONAL-f (R (filled-by-mass [FbM] Prefilled Pen, could be used to reconstitute Pergoveris TM (follitropin alfa/lutropin alfa 150 IU/75 IU lyophilized powder. In Ratio Groups 1 and 2, the r-hFSH:r-hLH ratio was 3:1; in Ratio Groups 3 and 4, the ratios of r-hFSH:r-hLH were 5:1 and 8:1, respectively. The protein content and bioactivity of each mixed solution were evaluated. The r-hFSH and r-hLH content was determined using reverse-phase high performance liquid chromatography. The biological activity of r-hFSH and r-hLH was assessed using the Steelman-Pohley and Van Hell in vivo bioassays in rats, respectively. Results Follitropin alfa/lutropin alfa 150 IU/75 IU lyophilized powder could be successfully mixed with follitropin alfa 75 IU FbM solution that was either reconstituted from lyophilized powder or injected directly from the prefilled pen to create solutions with ratios of r-hFSH and r-hLH from 3:1 to 8:1. The measured content of r-hFSH and r-hLH corresponded favourably with the target protein content in Ratio Groups 1–4. The in vivo target and measured bioactivity of r-hFSH and r-hLH were also closely matched in all Ratio Groups. Conclusion Follitropin alfa lyophilized powder or solution can be accurately mixed with follitropin alfa/lutropin alfa 150 IU/75 IU lyophilized powder to

  9. Single Amplified Genomes as Source for Novel Extremozymes: Annotation, Expression and Functional Assessment

    KAUST Repository

    Grötzinger, Stefan

    2017-12-01

    Enzymes, as nature’s catalysts, show remarkable abilities that can revolutionize the chemical, biotechnological, bioremediation, agricultural and pharmaceutical industries. However, the narrow range of stability of the majority of described biocatalysts limits their use for many applications. To overcome these restrictions, extremozymes derived from microorganisms thriving under harsh conditions can be used. Extremophiles living in high salinity are especially interesting as they operate at low water activity, which is similar to conditions used in standard chemical applications. Because only about 0.1 % of all microorganisms can be cultured, the traditional way of culture-based enzyme function determination needs to be overcome. The rise of high-throughput next-generation-sequencing technologies allows for deep insight into nature’s variety. Single amplified genomes (SAGs) specifically allow for whole genome assemblies from small sample volumes with low cell yields, as are typical for extreme environments. Although these technologies have been available for years, the expected boost in biotechnology has held off. One of the main reasons is the lack of reliable functional annotation of the genomic data, which is caused by the low amount (0.15 %) of experimentally described genes. Here, we present a novel annotation algorithm, designed to annotate the enzymatic function of genomes from microorganisms with low homologies to described microorganisms. The algorithm was established on SAGs from the extreme environment of selected hypersaline Red Sea brine pools with 4.3 M salinity and temperatures up to 68°C. Additionally, a novel consensus pattern for the identification of γ-carbonic anhydrases was created and applied in the algorithm. To verify the annotation, selected genes were expressed in the hypersaline expression system Halobacterium salinarum. This expression system was established and optimized in a continuously stirred tank reactor, leading to

  10. 'Single-checked' Patient Group Directions during initial nurse assessment within paediatric emergency departments of the UK and Ireland.

    Science.gov (United States)

    Bird, Chris K; Sinclair, Anthony G; Hartshorn, Stuart

    2017-01-10

    Double checking medications at initial assessment within paediatric emergency departments (EDs) has the potential to delay patient flow, and doubt has been cast on the efficacy of double checking in all but high-risk medications. We aimed to benchmark current practice for the use of Patient Group Direction (PGD) medications at initial assessment in EDs within the Paediatric Emergency Research UK and Ireland (PERUKI) network, with a focus on the use of 'single-checker' PGDs. Online survey was distributed to the research representative at each PERUKI site. The survey was open for 5 weeks (from March 2015 to April 2015) and was completed by any appropriate clinician within the site. The response rate was 84% (36/43 EDs). From these, 22 out of 36 (61%) EDs were using single-checker PGDs. The commonest single-checked medications in use were paracetamol and ibuprofen for pain. Among PERUKI sites, 21.9% of EDs reported drug errors related to standard (double-checked) PGDs, whereas 13.6% of those with single-checked PGDs reported drug errors (Fisher's exact test with significance level of 0.05, P=0.501). The commonest errors reported were duplicated dose, incorrect weight, incorrect volume drawn up, contraindication missed. Single-checker PGDs are currently in use in nearly two-thirds of PERUKI sites. No evidence of increased medication errors was reported with this practice; however, more detailed studies are required to support this finding and to inform best practice.

  11. Strapdown Airborne Gravimetry Quality Assessment Method Based on Single Survey Line Data: A Study by SGA-WZ02 Gravimeter.

    Science.gov (United States)

    Wang, Minghao; Wu, Meiping; Cao, Juliang; Zhang, Kaidong; Cai, Shaokun; Yu, Ruihang

    2018-01-26

    Quality assessment is an important part in the strapdown airborne gravimetry. Root mean square error (RMSE) evaluation method is a classical way to evaluate the gravimetry quality, but classical evaluation methods are preconditioned by extra flight or reference data. Thus, a method, which is able to largely conquer the premises of classical quality assessment methods and can be used in single survey line, has been developed in this paper. According to theoretical analysis, the method chooses the stability of two horizontal attitude angles, horizontal specific force and vertical specific force as the determinants of quality assessment method. The actual data, collected by SGA-WZ02 from 13 flights 21 lines in certain survey, was used to build the model and elaborate the method. To substantiate the performance of the quality assessment model, the model is applied in extra repeat line flights from two surveys. Compared with internal RMSE, standard deviation of assessment residuals are 0.23 mGal and 0.16 mGal in two surveys, which shows that the quality assessment method is reliable and stricter. The extra flights are not necessary by specially arranging the route of flights. The method, summarized from SGA-WZ02, is a feasible approach to assess gravimetry quality using single line data and is also suitable for other strapdown gravimeters.

  12. What do self-efficacy items measure? Examining the discriminant content validity of self-efficacy items.

    Science.gov (United States)

    Burrell, Alison M G; Allan, Julia L; Williams, David M; Johnston, Marie

    2018-03-08

    Self-efficacy - an individual's judgement of their ability to successfully perform a behaviour - is commonly used to explain and predict behaviour. It is measured through self-report questionnaires. These scales require good content validity, that is must measure the full scope and content of the construct without contamination from similar constructs. This study uses a systematic, transparent quantitative method (discriminant content validation, DCV) to assess the content validity of a variety of self-efficacy items and qualitatively explores participant interpretations of these items. A quantitative DCV and qualitative think-aloud study of self-efficacy item interpretation. Participants (n = 21) were presented with items designed to measure self-efficacy and related constructs following standard DCV methodology. Items were rated against construct definitions to determine whether they measured a particular construct (yes/no). Judges' confidence in each assessment was also assessed (%) and used to establish quantitative estimates of content validity for each item. A qualitative think-aloud study explored the judgements made in a subset of participants. 8/8 self-efficacy items were found to measure self-efficacy; however, 2/8 of these also measured motivation. 6/8 items displayed discriminant content validity and thus can be considered 'pure' measures of self-efficacy. The think-aloud study indicated that item wording is a likely cause of item misinterpretation. Self-efficacy items vary in terms of their content validity with only some of the items assessed providing 'pure' measures of the self-efficacy construct. Item wording should be considered during study design to avoid misinterpretation. Statement of contribution What is already known on this subject? For decades, questions have been raised relating to the content validity of self-efficacy scales, with suggestions of possible construct contamination. Previous studies have shown that manipulation of the

  13. Single-cell Western blotting after whole-cell imaging to assess cancer chemotherapeutic response.

    Science.gov (United States)

    Kang, Chi-Chih; Lin, Jung-Ming G; Xu, Zhuchen; Kumar, Sanjay; Herr, Amy E

    2014-10-21

    Intratumor heterogeneity remains a major obstacle to effective cancer therapy and personalized medicine. Current understanding points to differential therapeutic response among subpopulations of tumor cells as a key challenge to successful treatment. To advance our understanding of how this heterogeneity is reflected in cell-to-cell variations in chemosensitivity and expression of drug-resistance proteins, we optimize and apply a new targeted proteomics modality, single-cell western blotting (scWestern), to a human glioblastoma cell line. To acquire both phenotypic and proteomic data on the same, single glioblastoma cells, we integrate high-content imaging prior to the scWestern assays. The scWestern technique supports thousands of concurrent single-cell western blots, with each assay comprised of chemical lysis of single cells seated in microwells, protein electrophoresis from those microwells into a supporting polyacrylamide (PA) gel layer, and in-gel antibody probing. We systematically optimize chemical lysis and subsequent polyacrylamide gel electrophoresis (PAGE) of the single-cell lysate. The scWestern slides are stored for months then reprobed, thus allowing archiving and later analysis as relevant to sparingly limited, longitudinal cell specimens. Imaging and scWestern analysis of single glioblastoma cells dosed with the chemotherapeutic daunomycin showed both apoptotic (cleaved caspase 8- and annexin V-positive) and living cells. Intriguingly, living glioblastoma subpopulations show up-regulation of a multidrug resistant protein, P-glycoprotein (P-gp), suggesting an active drug efflux pump as a potential mechanism of drug resistance. Accordingly, linking of phenotype with targeted protein analysis with single-cell resolution may advance our understanding of drug response in inherently heterogeneous cell populations, such as those anticipated in tumors.

  14. A Simulated Single-Item Aggregate Inventory Model for U.S. Navy Repairable Items

    Science.gov (United States)

    1993-09-01

    carcass will be either lost or determined to be uneconomical to repair. 1. Definition of termo Define Q. as the procurement quantity of new material...the simulation clock reaches a user designated time, or after a user designated event occurs a given number of times. This parameter is established...relationships, is discussed in section D below. 4. Output Obtaining data from a SIGMA simulation is not a difficult task. The user simply designates the state

  15. 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…

  16. 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...

  17. A Methodology for Zumbo's Third Generation DIF Analyses and the Ecology of Item Responding

    Science.gov (United States)

    Zumbo, Bruno D.; Liu, Yan; Wu, Amery D.; Shear, Benjamin R.; Olvera Astivia, Oscar L.; Ark, Tavinder K.

    2015-01-01

    Methods for detecting differential item functioning (DIF) and item bias are typically used in the process of item analysis when developing new measures; adapting existing measures for different populations, languages, or cultures; or more generally validating test score inferences. In 2007 in "Language Assessment Quarterly," Zumbo…

  18. 76 FR 58138 - Defense Federal Acquisition Regulation Supplement (DFARS); Alternative Line Item Structure (DFARS...

    Science.gov (United States)

    2011-09-20

    ... problems in the receipt and acceptance phase for contract deliverables and payments. This group determined..., inspection, acceptance and payment. Line items are organized into contract line items, subline items, and... that assessed destination-acceptance procedures. The process reviews performed by DoD cross-service...

  19. Gender-, age- and race/ethnicity-based Differential Item Functioning (DIF) analysis of MDS-UPDRS

    Science.gov (United States)

    Goetz, Christopher G.; Liu, Yuanyuan; Stebbins, Glenn T.; Wang, Lu; Tilley, Barbara C.; Teresi, Jeanne A.; Merkitch, Douglas; Luo, Sheng

    2016-01-01

    Objective Assess MDS-UPDRS items for gender-, age-, and race/ethnicity-based Differential Item Functioning. Background Assessing Differential Item Functioning is a core rating scale validation step. For the MDS-UPDRS, Differential Item Functioning occurs if item-score probability among people with similar levels of parkinsonism differ according to selected covariates (gender, age, race/ethnicity). If the magnitude of Differential Item Functioning is clinically relevant, item-score interpretation must consider influences by these covariates. Differential Item Functioning can be Non-uniform (covariate variably influences an item-score across different levels of parkinsonism) or Uniform (covariate influences an item-score consistently over all levels of parkinsonism. Methods Using the MDS-UPDRS translation database of over 5,000 PD patients from fourteen languages, we tested gender-, age-, and race/ethnicity-based Differential Item Functioning. To designate an item as having clinically relevant Differential Item Functioning, we required statistical confirmation by two independent methods, along with a McFadden pseudo-R2 magnitude statistic greater than “negligible.” Results Most items showed no gender-, age- or race/ethnicity-based Differential Item Functioning. When Differential Item Functioning was identified, the magnitude statistic was always in the “negligible” range, and the scale level impact was minimal. Conclusions The absence of clinically relevant Differential Item Functioning across all items and all Parts of MDS-UPDRS is strong evidence that the scale can be used confidently. As studies of Parkinson's disease increasingly involve multinational efforts and the MDS-UPDRS has several validated non-English translations, the findings support the scale's broad applicability in populations with varying gender, age, and race/ethnicity distributions. PMID:27943473

  20. Assessment of vadose zone radionuclide contamination around Single Shell Tank 241-C-103

    International Nuclear Information System (INIS)

    Kos, S.E.

    1995-12-01

    Five drywells surrounding single shell tank 241-C-103 were logged with the high-purity germanium logging system to investigate possible leakage of radioactive contamination from the tank. The investigation included integration of the drywell survey results with several other data sources. There is no conclusive evidence showing indications that the 241-C-103 tank has leaked

  1. Comparison of PASS Assessment Scores in Single-Gender and Heterogeneous Middle Schools in South Carolina

    Science.gov (United States)

    Canada, Patricia Oxendine

    2012-01-01

    In response to the mandates of No Child Left Behind, (NCLB), educators across the country struggle to close the gaps between males and females. Some of the physiological differences existing between the male and female brain suggest support for single-gender instruction, which is on the rise within this country as well as other parts of the world.…

  2. Risk assessment for Helicoverpa zea (Lepidoptera: Noctuidae) resistance on dual-gene versus single-gene corn.

    Science.gov (United States)

    Edwards, Kristine T; Caprio, Michael A; Allen, K Clint; Musser, Fred R

    2013-02-01

    Recent Environmental Protection Agency (EPA) decisions regarding resistance management in Bt-cropping systems have prompted concern in some experts that dual-gene Bt-corn (CrylA.105 and Cry2Ab2 toxins) may result in more rapid selection for resistance in Helicoverpa zea (Boddie) than single-gene Bacillus thuringiensis (Bt)-corn (CrylAb toxin). The concern is that Bt-toxin longevity could be significantly reduced with recent adoption of a natural refuge for dual-gene Bt-cotton (CrylAc and Cry2Ab2 toxins) and concurrent reduction in dual-gene corn refuge from 50 to 20%. A population genetics framework that simulates complex landscapes was applied to risk assessment. Expert opinions on effectiveness of several transgenic corn and cotton varieties were captured and used to assign probabilities to different scenarios in the assessment. At least 350 replicate simulations with randomly drawn parameters were completed for each of four risk assessments. Resistance evolved within 30 yr in 22.5% of simulations with single-gene corn and cotton with no volunteer corn. When volunteer corn was added to this assessment, risk of resistance evolving within 30 yr declined to 13.8%. When dual-gene Bt-cotton planted with a natural refuge and single-gene corn planted with a 50% structured refuge was simulated, simultaneous resistance to both toxins never occurred within 30 yr, but in 38.5% of simulations, resistance evolved to toxin present in single-gene Bt-corn (CrylAb). When both corn and cotton were simulated as dual-gene products, cotton with a natural refuge and corn with a 20% refuge, 3% of simulations evolved resistance to both toxins simultaneously within 30 yr, while 10.4% of simulations evolved resistance to CrylAb/c toxin.

  3. 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

  4. Implementation Plan for Tank Farm Transition Projects Suspect and Counterfeit Items

    International Nuclear Information System (INIS)

    TRUE, R.R.

    2000-01-01

    This plan is designed to provide an appropriate level of confidence that Tank Farm Transition Projects (TFTP) facilities will be evaluated to assess the presence of suspect/counterfeit items. It is intended to identify suspect/counterfeit items that are presently in inventory and provide for the reporting and disposition of those items. Items which have been installed will also receive appropriate evaluation using a graded approach to achieve optimum results balanced against safety considerations and cost effectiveness

  5. The accuracy of individual self-reported items to determine periodontal disease history.

    Science.gov (United States)

    Dietrich, Thomas; Stosch, Ulrike; Dietrich, Dieter; Schamberger, Daniela; Bernimoulin, Jean-Pierre; Joshipura, Kaumudi

    2005-04-01

    The objective of this study was to evaluate the validity of self-reported periodontal disease and symptoms to predict periodontal disease history in a German population. We analysed data from 246 patients who answered a self-administered questionnaire on self-perceived periodontal disease and self-reported symptoms of periodontal disease. Actual periodontal status was assessed from panoramic radiographs and periodontal disease was defined as > or = 3 teeth with radiographic alveolar bone loss (ABL) > 5 mm (prevalence 39%). Sensitivity (SN) and specificity (SP) of self-reported items for diagnosis of periodontal disease history were calculated. The diagnostic accuracy of any individual item was generally low. For example, self-perceived periodontal disease had SN of 49% and SP of 67%. All self-reported items had low sensitivity, while self-reported professionally diagnosed bone loss, tooth loss caused by periodontal disease and mobility had SP > 90%. In conclusion, we did not identify a single individual question that can assess periodontal disease from self-reporting with satisfactory validity. Future studies will evaluate whether multivariate prediction rules using information from several self-reported variables are a valid means to ascertain periodontal disease history.

  6. A Feasibility Assessment of a Single Contracting Office for Common-User Transportation Services

    Science.gov (United States)

    1990-09-01

    Defense should establish a single unified command to integrate global air, land, and sea transportation, and should have flexibility to structure this...34provide global land, sea, and air transportation to meet national security needs" (66:22). By meeting the research objectives and answering the research... Bussiness Daily RCAS of Proposal (RFP) (TRCR & LGCR) (CBD) Requirenent Carriers Request Carriers Submit IRCAS Evaluates Award Based on Copy of RFP Proposals

  7. ASSESSMENT of POTENTIAL CARBON DIOXIDE-BASED DEMAND CONTROL VENTILATION SYSTEM PERFORMANCE in SINGLE ZONE SYSTEMS

    Science.gov (United States)

    2013-03-21

    requirements of a 400 m3 space in a multiuse facility in South Korea using two types of DCV systems—one CO2-based and the other uses a radio frequency...identification (RFID) device to detect zone occupancy 25 (Jeong et al., 2010). A dedicated outdoor air system supplies ventilation air to the zone...use a known control scheme (ASHRAE, 2010b). Carbon Dioxide Sensor Modeling Case Study 2 While the first case study examines a single multiuse

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

    Science.gov (United States)

    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.

  9. Comparison of the neural correlates of encoding item-item and item-context associations

    Directory of Open Access Journals (Sweden)

    Jenny X Wong

    2013-08-01

    Full Text Available fMRI was employed to investigate the role of the left inferior frontal gyrus (LIFG in the encoding of item-item and item-context associations. On each of a series of study trials subjects viewed a picture that was presented either to the left or right of fixation, along with a subsequently presented word that appeared at fixation. Memory was tested in a subsequent memory test that took place outside of the scanner. On each test trial one of two forced choice judgments was required. For the associative test, subjects chose between the word paired with the picture at study and a word studied on a different trial. For the source test, the judgment was whether the picture had been presented on the left or right. Successful encoding of associative information was accompanied by subsequent memory effects in several cortical regions, including much of the LIFG. By contrast, successful source encoding was selectively associated with a subsequent memory effect in right fusiform cortex. The finding that the LIFG was enhanced during successful associative, but not source, encoding is interpreted in light of the proposal that subsequent memory effects are localized to cortical regions engaged by the on-line demands of the study task.

  10. Optimisation and validation of methods to assess single nucleotide polymorphisms (SNPs) in archival histological material

    DEFF Research Database (Denmark)

    Andreassen, C N; Sørensen, Flemming Brandt; Overgaard, J

    2004-01-01

    only archival specimens are available. This study was conducted to validate protocols optimised for assessment of SNPs based on paraffin embedded, formalin fixed tissue samples. PATIENTS AND METHODS: In 137 breast cancer patients, three TGFB1 SNPs were assessed based on archival histological specimens...... precipitation). RESULTS: Assessment of SNPs based on archival histological material is encumbered by a number of obstacles and pitfalls. However, these can be widely overcome by careful optimisation of the methods used for sample selection, DNA extraction and PCR. Within 130 samples that fulfil the criteria...

  11. Numerosity estimates for attended and unattended items in visual search.

    Science.gov (United States)

    Kelley, Troy D; Cassenti, Daniel N; Marusich, Laura R; Ghirardelli, Thomas G

    2017-07-01

    The goal of this research was to examine memories created for the number of items during a visual search task. Participants performed a visual search task for a target defined by a single feature (Experiment 1A), by a conjunction of features (Experiment 1B), or by a specific spatial configuration of features (Experiment 1C). On some trials following the search task, subjects were asked to recall the total number of items in the previous display. In all search types, participants underestimated the total number of items, but the severity of the underestimation varied depending on the efficiency of the search. In three follow-up studies (Experiments 2A, 2B, and 2C) using the same visual stimuli, the participants' only task was to estimate the number of items on each screen. Participants still underestimated the numerosity of the items, although the degree of underestimation was smaller than in the search tasks and did not depend on the type of visual stimuli. In Experiment 3, participants were asked to recall the number of items in a display only once. Subjects still displayed a tendency to underestimate, indicating that the underestimation effects seen in Experiments 1A-1C were not attributable to knowledge of the estimation task. The degree of underestimation depends on the efficiency of the search task, with more severe underestimation in efficient search tasks. This suggests that the lower attentional demands of very efficient searches leads to less encoding of numerosity of the distractor set.

  12. Concordance between timeline follow-back and single-question assessment of self-reported smoking in a clinical trial.

    Science.gov (United States)

    Bernstein, Steven L; Rosner, June; Toll, Benjamin

    2016-01-01

    Smoking cessation clinical trials assess tobacco abstinence using self-report and biomarkers. Optimum methods for each are unclear; a common question assesses smoking in the prior 7 days. In contrast, timeline follow-back (TLFB) is another technique often used to assess use of alcohol in treatment trials; it is used less frequently in studies of smoking cessation. The goal of this study was to assess concordance between the 7-day smoking question and a 7-day TLFB. Secondary analysis of data from a randomized clinical trial of smoking cessation was conducted at a busy, urban hospital emergency department (ED) from October 2010 to December 2012. At 1, 3, and 12 months, subjects were contacted by phone to assess smoking status. Those reporting abstinence at 3 months were asked to return for an in-person measurement of exhaled carbon monoxide. For this analysis, smoking status at 1 month was compared for subjects in response to 2 questions asked concurrently, addressing 7-day point prevalence tobacco use and a 7-day TLFB. Of 780 subjects, 666 (85.4%) were available for 1-month follow-up. Of these, 99 (14.9%) reported no smoking in response to the 7-day question, and 96 (14.4%) reported no smoking in response to the 7-day TLFB. The overall proportionate agreement between the 2 methods was 98.6%, with a kappa of 0.95 (95% confidence interval [CI]: 0.91-0.98). A single question that assesses smoking at 7 days provides excellent concordance with the more detailed TLFB. The single question appears adequate to assess self-reported tobacco use in clinical trials of smoking cessation.

  13. Good exams made easy: The item management system for multiple examination formats

    Directory of Open Access Journals (Sweden)

    Hochlehnert Achim

    2012-08-01

    Full Text Available Abstract Background The development, implementation and evaluation of assessments require considerable resources and often cannot be carried out by a single faculty/institution. Therefore some medical faculties have founded cooperation projects which mainly focus on the exchange of multiple choice questions (MCQs. Methods Since these cooperation projects do not entirely support all relevant processes in terms of preparation, implementation and evaluation of assessment, in 2006 the Medical Assessment Alliance (MAA was founded for mutual support. In addition to MCQs the MAA started to develop innovative assessment formats and facilitate content through a coordinated exchange of experiences. To support cooperation within this network, the web-based Item Management System (IMS was developed which supports all processes of the assessment workflow as an all-in-one working platform. Results At present, the Alliance has 28 partner faculties in Europe. More than 2.800 users in 750 working groups are collaborating. Currently 90.000 questions have been stored in the IMS. Since 2007, nearly 4.600 examinations have been successfully conducted. Conclusion This article describes in detail the unique features of the IMS and contrasts it with the item management systems of other associations.

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

    Science.gov (United States)

    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.

  15. The National Single Assessment Tool (SAT) a pilot study in older persons care-survey results.

    Science.gov (United States)

    McDermott-Scales, L; Beaton, D; McMahon, F; Vereker, N; McCormack, B; Coen, R F; O'Keefe, S T

    2013-01-01

    Following a consultation and review process, the interRAI suite of assessment tools was chosen as the most suitable instrument for assessment of the care needs of older people in Ireland. We used previously validated questionnaires to examine the usability, practicality and acceptability of these tools to professionals, carers and clients in rural and urban acute, long-term care and community settings. Of the 45 professionals, 42-44 (93-98%) agreed or strongly agreed with 14 of 15 positive statements regarding the acceptability, clinical value and ease of use of the interRAl tools; 39 (87%) felt the terminology was consistent and familiar, although 35 (78%) felt some areas would require further explanation. Responses from carers (n = 15) and clients (n = 68) were similarly overwhelmingly positive regarding the experience of being assessed using these tools. These results support the clinical utility and practicality of using this approach to assess older people in Irish clinical practice.

  16. A phase I study to assess the single and multiple dose pharmacokinetics of THC/CBD oromucosal spray.

    Science.gov (United States)

    Stott, C G; White, L; Wright, S; Wilbraham, D; Guy, G W

    2013-05-01

    A Phase I study to assess the single and multipledose pharmacokinetics (PKs) and safety and tolerability of oromucosally administered Δ(9)-tetrahydrocannabinol (THC)/cannabidiol (CBD) spray, an endocannabinoid system modulator, in healthy male subjects. Subjects received either single doses of THC/CBD spray as multiple sprays [2 (5.4 mg THC and 5.0 mg CBD), 4 (10.8 mg THC and 10.0 mg CBD) or 8 (21.6 mg THC and 20.0 mg CBD) daily sprays] or multiple doses of THC/CBD spray (2, 4 or 8 sprays once daily) for nine consecutive days, following fasting for a minimum of 10 h overnight prior to each dosing. Plasma samples were analyzed by gas chromatography-mass spectrometry for CBD, THC, and its primary metabolite 11-hydroxy-THC, and various PK parameters were investigated. Δ(9)-Tetrahydrocannabinol and CBD were rapidly absorbed following single-dose administration. With increasing single and multiple doses of THC/CBD spray, the mean peak plasma concentration (Cmax) increased for all analytes. There was evidence of dose-proportionality in the single but not the multiple dosing data sets. The bioavailability of THC was greater than CBD at single and multiple doses, and there was no evidence of accumulation for any analyte with multiple dosing. Inter-subject variability ranged from moderate to high for all PK parameters in this study. The time to peak plasma concentration (Tmax) was longest for all analytes in the eight spray group, but was similar in the two and four spray groups. THC/CBD spray was well-tolerated in this study and no serious adverse events were reported. The mean Cmax values (<12 ng/mL) recorded in this study were well below those reported in patients who smoked/inhaled cannabis, which is reassuring since elevated Cmax values are linked to significant psychoactivity. There was also no evidence of accumulation on repeated dosing.

  17. Components of item selection algorithm in computerized adaptive testing.

    Science.gov (United States)

    Han, Kyung T

    2018-03-24

    Computerized adaptive testing (CAT) greatly improves measurement efficiency in high-stakes testing operations through the selection and administration of test items whose difficulty level is most relevant to each individual test taker. This paper explains the three components of a conventional CAT item selection algorithm-test content balancing, item selection criterion, and item exposure control. There were several noteworthy methodologies underlying each component. Test script method and constrained CAT method were for test content balancing. As for item selection criteria, there wereThe maximized Fisher information criterion, b-matching method, a-stratification method, weighted likelihood information criterion, efficiency balanced information criterion, and Kullback-Leibler information criterion.The randomesque method, Sympson-Hetter method, the unconditional and conditional multinomial methods, and the fade-away method were for item exposure control. Threre were several holistic approaches to CAT using the automated test assembly methods such as the shadow test approach and the weighted deviation model. Item usage and exposure count were variable according to the different item selection criteria and exposure control methods.. Finally, another important factors to consider when determining an appropriate CAT design are computer resources requirement, size of items, and the test length. . Logic of CAT is now being adopted in "adaptive learning," which integrates the learning aspect and the (formative) assessment aspect of education into a continuous, individualized learning experience. Therefore, the algorithms and technologies in this review may be able to help medical health educators and high stakes test takers to adopt CAT more actively and efficiently.

  18. Spatial assessment of wolf-dog hybridization in a single breeding period

    OpenAIRE

    Pacheco, C.; L?pez-Bao, J. V.; Garc?a, E. J.; Lema, F. J.; Llaneza, L.; Palacios, V.; Godinho, R.

    2017-01-01

    Understanding the dynamics of wolf-dog hybridization and delineating evidence-based conservation strategies requires information on the spatial extent of wolf-dog hybridization in real-time, which remains largely unknown. We collected 332 wolf-like scats over ca. 5,000km2 in the NW Iberian Peninsula to evaluate wolf-dog hybridization at population level in a single breeding/pup-rearing season. Mitochondrial DNA (MtDNA) and 18 ancestry informative markers were used for species and individual i...

  19. Single-Cell Genome-Wide Bisulfite Sequencing for Assessing Epigenetic Heterogeneity

    Science.gov (United States)

    Angermueller, Christof; Krueger, Felix; Saadeh, Heba; Peat, Julian; Andrews, Simon R; Stegle, Oliver; Reik, Wolf; Kelsey, Gavin

    2014-01-01

    We report a single-cell bisulfite sequencing method (scBS-Seq) capable of accurately measuring DNA methylation at up to 48.4% of CpGs. We observed that ESCs grown in serum or 2i both display epigenetic heterogeneity, with “2i-like” cells present in serum cultures. In silico integration of 12 individual mouse oocyte datasets largely recapitulates the whole DNA methylome, making scBS-Seq a versatile tool to explore DNA methylation in rare cells and heterogeneous populations. PMID:25042786

  20. Single cell adhesion strength assessed with variable-angle total internal reflection fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Marcelina Cardoso Dos Santos

    2017-06-01

    Full Text Available We propose a new strategy to evaluate adhesion strength at the single cell level. This approach involves variable-angle total internal reflection fluorescence microscopy to monitor in real time the topography of cell membranes, i.e. a map of the membrane/substrate separation distance. According to the Boltzmann distribution, both potential energy profile and dissociation energy related to the interactions between the cell membrane and the substrate were determined from the membrane topography. We have highlighted on glass substrates coated with poly-L-lysine and fibronectin, that the dissociation energy is a reliable parameter to quantify the adhesion strength of MDA-MB-231 motile cells.

  1. Dynamics Assessment of Grid-Synchronization Algorithms for Single-Phase Grid-Connected Converters

    DEFF Research Database (Denmark)

    Han, Yang; Luo, Mingyu; Guerrero, Josep M.

    2015-01-01

    and low computational burden. Meanwhile, some other techniques have been proposed to enhance system robustness and stability characteristics. In this paper, a comprehensive comparison among the OSG-based PLLs and the advanced single-phase PLLs is presented when the grid voltage undergoes disturbances......, and the performance comparison of transient response and disturbance rejection capabilities are presented. Finally, the moving average filter (MAF) is applied to enhance steady state and dynamic response of the delayed-type PLL, derivator-based PLL and the complex-coefficient filter (CCF-PLL) under grid frequency...

  2. Single-photon emission CT in the assessment of low back pain in young athletes

    International Nuclear Information System (INIS)

    Johnson, G.T.; Lagatutta, F.P.; Lazarus, M.L.; Faulkner, T.J.; Nolan, J.P.

    1991-01-01

    Fifty-two teenage and young adult athletes (ages 12-24 years) with low back pain (LBP) underwent routine lumbar radiography and bone scintigraphy including planar and single-photon CT and SPECT imaging. This paper illustrates the significant limitations of routine radiography and the importance of SPECT bone scintigraphy in evaluating young athletes with LBP and suspected spondylolysis; the increased sensitivity and specificity of SPECT compared to planar scintigraphy in the diagnosis of spondylolysis; and the potential utility of follow-up SPECT studies in evaluating success of therapy in athletes with initially positive diagnostic indicators for spondylolysis or impending spondylolysis

  3. Assessment of parental tooth-brushing following instruction with single-headed and triple-headed toothbrushes.

    Science.gov (United States)

    Telishevesky, Yoel S; Levin, Liran; Ashkenazi, Malka

    2012-01-01

    The purpose of this study was to evaluate the effect of toothbrush design on the ability of parents to effectively brush their children's teeth. Parents of children (mean age=5.1±0.75 years old) from 4 kindergarten schools were randomly assigned to receive instruction in brushing their children's teeth using a manual single-headed toothbrush (2 schools) or a triple-headed toothbrush (2 schools). The parents' ability to brush their children's teeth was evaluated according to a novel toothbrush performing skill index (Ashkenazi Index), based on 2 criteria: (1) placement of the toothbrush on each tooth segment to be brushed ("reach"); and (2) completion of enough strokes on each segment ("stay"). One month after instruction, tooth-brushing ability was re-evaluated and plaque index of the children's teeth was assessed. One month after instruction, parents using the triple-headed toothbrush received significantly higher scores on the tooth-brushing performance index (~86%), than did those in the single-headed group (~61%; P=.001). The plaque index was significantly higher in the single-headed group (0.97±0.38) vs the triple-headed group (0.72±0.29; Pbrushing performance index correlated negatively with the plaque index (Pbrushing by parents than does a single-headed toothbrush.

  4. Comparing the Use of 3D Photogrammetry and Computed Tomography in Assessing the Severity of Single-Suture Nonsyndromic Craniosynostosis.

    Science.gov (United States)

    Ho, Olivia A; Saber, Nikoo; Stephens, Derek; Clausen, April; Drake, James; Forrest, Christopher; Phillips, John

    2017-05-01

    Single-suture nonsyndromic craniosynostosis is diagnosed using clinical assessment and computed tomography (CT). With increasing awareness of the associated risks of radiation exposure, the use of CT is particularly concerning in patients with craniosynostosis since they are exposed at a younger age and more frequently than the average child. Three-dimensional (3D) photogrammetry is advantageous-it involves no radiation, is conveniently obtainable within clinic, and does not require general anaesthesia. This study aims to assess how 3D photogrammetry compares to CT in the assessment of craniosynostosis severity, to quantify surgical outcomes, and analyze the validity of 3D photogrammetry in craniosynostosis. Computed tomography images and 3D photographs of patients who underwent craniosynostosis surgery were assessed and aligned to best fit. The intervening area between the CT and 3D photogrammetry curves at the supraorbital bar (bandeau) level in axial view was calculated. Statistical analysis was performed using Student t test. Ninety-five percent confidence intervals were determined and equivalence margins were applied. In total, 41 pairs of CTs and 3D photographs were analyzed. The 95% confidence interval was 198.16 to 264.18 mm 2 and the mean was 231.17 mm 2 . When comparisons were made in the same bandeau region omitting the temporalis muscle, the 95% confidence interval was 108.94 to 147.38 mm 2 , and the mean was 128.16 mm 2 . Although statistically significant difference between the modalities was found, they can be attributable to the dampening effect of soft tissue. Within certain error margins, 3D photogrammetry is comparable to CT in assessing the severity of single-suture nonsyndromic craniosynostosis. However, a dampening effect can be attributable to the soft tissue. Three-dimensional photogrammetry may be more applicable for severe cases of craniosynostosis but not milder deformity. It may also be beneficial for assessing the overall appearance and

  5. A Bifactor Multidimensional Item Response Theory Model for Differential Item Functioning Analysis on Testlet-Based Items

    Science.gov (United States)

    Fukuhara, Hirotaka; Kamata, Akihito

    2011-01-01

    A differential item functioning (DIF) detection method for testlet-based data was proposed and evaluated in this study. The proposed DIF model is an extension of a bifactor multidimensional item response theory (MIRT) model for testlets. Unlike traditional item response theory (IRT) DIF models, the proposed model takes testlet effects into…

  6. Emergency Power For Critical Items

    Science.gov (United States)

    Young, William R.

    2009-07-01

    Natural disasters, such as hurricanes, floods, tornados, and tsunami, are becoming a greater problem as climate change impacts our environment. Disasters, whether natural or man made, destroy lives, homes, businesses and the natural environment. Such disasters can happen with little or no warning, leaving hundreds or even thousands of people without medical services, potable water, sanitation, communications and electrical services for up to several weeks. In our modern world, the need for electricity has become a necessity. Modern building codes and new disaster resistant building practices are reducing the damage to homes and businesses. Emergency gasoline and diesel generators are becoming common place for power outages. Generators need fuel, which may not be available after a disaster, but Photovoltaic (solar-electric) systems supply electricity without petroleum fuel as they are powered by the sun. Photovoltaic (PV) systems can provide electrical power for a home or business. PV systems can operate as utility interactive or stand-alone with battery backup. Determining your critical load items and sizing the photovoltaic system for those critical items, guarantees their operation in a disaster.

  7. Multiple true-false items: a comparison of scoring algorithms.

    Science.gov (United States)

    Lahner, Felicitas-Maria; Lörwald, Andrea Carolin; Bauer, Daniel; Nouns, Zineb Miriam; Krebs, René; Guttormsen, Sissel; Fischer, Martin R; Huwendiek, Sören

    2017-11-30

    Multiple true-false (MTF) items are a widely used supplement to the commonly used single-best answer (Type A) multiple choice format. However, an optimal scoring algorithm for MTF items has not yet been established, as existing studies yielded conflicting results. Therefore, this study analyzes two questions: What is the optimal scoring algorithm for MTF items regarding reliability, difficulty index and item discrimination? How do the psychometric characteristics of different scoring algorithms compare to those of Type A questions used in the same exams? We used data from 37 medical exams conducted in 2015 (998 MTF and 2163 Type A items overall). Using repeated measures analyses of variance (rANOVA), we compared reliability, difficulty and item discrimination of different scoring algorithms for MTF with four answer options and Type A. Scoring algorithms for MTF were dichotomous scoring (DS) and two partial credit scoring algorithms, PS 50 where examinees receive half a point if more than half of true/false ratings were marked correctly and one point if all were marked correctly, and PS 1/n where examinees receive a quarter of a point for every correct true/false rating. The two partial scoring algorithms showed significantly higher reliabilities (α PS1/n  = 0.75; α PS50  = 0.75; α DS  = 0.70, α A  = 0.72), which corresponds to fewer items needed for a reliability of 0.8 (n PS1/n  = 74; n PS50  = 75; n DS  = 103, n A  = 87), and higher discrimination indices (r PS1/n  = 0.33; r PS50  = 0.33; r DS  = 0.30; r A  = 0.28) than dichotomous scoring and Type A. Items scored with DS tend to be difficult (p DS  = 0.50), whereas items scored with PS 1/n become easy (p PS1/n  = 0.82). PS 50 and Type A cover the whole range, from easy to difficult items (p PS50  = 0.66; p A  = 0.73). Partial credit scoring leads to better psychometric results than dichotomous scoring. PS 50 covers the range from easy to difficult items better than PS 1/n

  8. The REFANI-S study protocol: a non-randomised cluster controlled trial to assess the role of an unconditional cash transfer, a non-food item kit, and free piped water in reducing the risk of acute malnutrition among children aged 6–59 months living in camps for internally displaced persons in the Afgooye corridor, Somalia

    Directory of Open Access Journals (Sweden)

    Mohamed Jelle

    2017-07-01

    Full Text Available Abstract Background The prevalence of acute malnutrition is often high in emergency-affected populations and is associated with elevated mortality risk and long-term health consequences. Increasingly, cash transfer programmes (CTP are used instead of direct food aid as a nutritional intervention, but there is sparse evidence on their nutritional impact. We aim to understand whether CTP reduces acute malnutrition and its known risk factors. Methods/design A non-randomised, cluster-controlled trial will assess the impact of an unconditional cash transfer of US$84 per month for 5 months, a single non-food items kit, and free piped water on the risk of acute malnutrition in children, aged 6–59 months. The study will take place in camps for internally displaced persons (IDP in peri-urban Mogadishu, Somalia. A cluster will consist of one IDP camp and 10 camps will be allocated to receive the intervention based on vulnerability targeting criteria. The control camps will then be selected from the same geographical area. Needs assessment data indicates small differences in vulnerability between camps. In each trial arm, 120 households will be randomly sampled and two detailed household surveys will be implemented at baseline and 3 months after the initiation of the cash transfer. The survey questionnaire will cover risk factors for malnutrition including household expenditure, assets, food security, diet diversity, coping strategies, morbidity, WASH, and access to health care. A community surveillance system will collect monthly mid-upper arm circumference measurements from all children aged 6–59 months in the study clusters to assess the incidence of acute malnutrition over the duration of the intervention. Process evaluation data will be compiled from routine quantitative programme data and primary qualitative data collected using key informant interviews and focus group discussions. The UK Department for International Development will provide

  9. The REFANI-S study protocol: a non-randomised cluster controlled trial to assess the role of an unconditional cash transfer, a non-food item kit, and free piped water in reducing the risk of acute malnutrition among children aged 6-59 months living in camps for internally displaced persons in the Afgooye corridor, Somalia.

    Science.gov (United States)

    Jelle, Mohamed; Grijalva-Eternod, Carlos S; Haghparast-Bidgoli, Hassan; King, Sarah; Cox, Cassy L; Skordis-Worrall, Jolene; Morrison, Joanna; Colbourn, Timothy; Fottrell, Edward; Seal, Andrew J

    2017-07-06

    The prevalence of acute malnutrition is often high in emergency-affected populations and is associated with elevated mortality risk and long-term health consequences. Increasingly, cash transfer programmes (CTP) are used instead of direct food aid as a nutritional intervention, but there is sparse evidence on their nutritional impact. We aim to understand whether CTP reduces acute malnutrition and its known risk factors. A non-randomised, cluster-controlled trial will assess the impact of an unconditional cash transfer of US$84 per month for 5 months, a single non-food items kit, and free piped water on the risk of acute malnutrition in children, aged 6-59 months. The study will take place in camps for internally displaced persons (IDP) in peri-urban Mogadishu, Somalia. A cluster will consist of one IDP camp and 10 camps will be allocated to receive the intervention based on vulnerability targeting criteria. The control camps will then be selected from the same geographical area. Needs assessment data indicates small differences in vulnerability between camps. In each trial arm, 120 households will be randomly sampled and two detailed household surveys will be implemented at baseline and 3 months after the initiation of the cash transfer. The survey questionnaire will cover risk factors for malnutrition including household expenditure, assets, food security, diet diversity, coping strategies, morbidity, WASH, and access to health care. A community surveillance system will collect monthly mid-upper arm circumference measurements from all children aged 6-59 months in the study clusters to assess the incidence of acute malnutrition over the duration of the intervention. Process evaluation data will be compiled from routine quantitative programme data and primary qualitative data collected using key informant interviews and focus group discussions. The UK Department for International Development will provide funding for this study. The European Civil Protection and

  10. Epilogue: Reading Comprehension Is Not a Single Ability--Implications for Assessment and Instruction

    Science.gov (United States)

    Kamhi, Alan G.; Catts, Hugh W.

    2017-01-01

    Purpose: In this epilogue, we review the 4 response articles and highlight the implications of a multidimensional view of reading for the assessment and instruction of reading comprehension. Method: We reiterate the problems with standardized tests of reading comprehension and discuss the advantages and disadvantages of recently developed…

  11. Correlation between Single Assessment Numerical Evaluation score and Lysholm score in primary total knee arthroplasty patients

    Directory of Open Access Journals (Sweden)

    Ted Sueyoshi, ATC, PES

    2018-03-01

    Conclusions: The results of the investigation showed that there was a statistically significant, however relatively weak, correlation between SANE score and Lysholm score. SANE score may serve as an alternative method to assess TKA patients' subjective post-operative outcomes to Lysholm score.

  12. The reliability and criterion validity of 2D video assessment of single leg squat and hop landing.

    Science.gov (United States)

    Herrington, Lee; Alenezi, Faisal; Alzhrani, Msaad; Alrayani, Hasan; Jones, Richard

    2017-06-01

    The objective was to assess the intra-tester, within and between day reliability of measurement of hip adduction (HADD) and frontal plane projection angles (FPPA) during single leg squat (SLS) and single leg landing (SLL) using 2D video and the validity of these measurements against those found during 3D motion capture. 15 healthy subjects had their SLS and SLL assessed using 3D motion capture and video analysis. Inter-tester reliability for both SLS and SLL when measuring FPPA and HADD show excellent correlations (ICC 2,1 0.97-0.99). Within and between day assessment of SLS and SLL showed good to excellent correlations for both variables (ICC 3,1 0.72-91). 2D FPPA measures were found to have good correlation with knee abduction angle in 3-D (r=0.79, p=0.008) during SLS, and also to knee abduction moment (r=0.65, p=0.009). 2D HADD showed very good correlation with 3D HADD during SLS (r=0.81, p=0.001), and a good correlation during SLL (r=0.62, p=0.013). All other associations were weak (r<0.4). This study suggests that 2D video kinematics have a reasonable association to what is being measured with 3D motion capture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Reliability assessment of single-phase grid-connected PV microinverters considering mission profile and uncertainties

    DEFF Research Database (Denmark)

    Zare, Mohammad Hadi; Mohamadian, Mustafa; Wang, Huai

    2017-01-01

    Microinverters usually connect a PV panel to a Single-phase power grid. In such system, the input power is constant while the output power oscillates twice the line frequency. Thus, the input and output power differences should be stored in a storage component, which is typically an electrolytic...... capacitor. However, electrolytic capacitors are usually blamed for their short lifetime. Recently, some active power decoupling methods are introduced in the literature which can takes advantage of high reliable film capacitors. However, some extra switches and diodes are added to the microinverter which...... can influence the microinverter lifetime. This paper investigates the microinverter reliability according to mission profile where it is installed. To get more accurate results, uncertainties in both lifetime model and manufacturing process are considered. The effect of ambient temperature and solar...

  14. Siting analysis and risk assessment for small single-purpose heating reactors

    International Nuclear Information System (INIS)

    Tarjanne, R.

    1979-04-01

    Two alternative sites both 10km away from the centre of Helsinki are considered for reactor unit sizes of 400mw and 800mw. The risks associated with a small single-purpose heating reactor is evaluated for normal operation and accident conditions. The evaluation for accident condition is performed for three characteristics accidents. Three pathways are considered in the calculation of the radiation exposure: direct external gamma dose from the release plume, direct gamma radiation from deposited activity on the ground and dose due to inhalation. The risks are compared with the risks from alternative conventional fossil fuelled district heat production methods. The results show that the heating reactor alternative causes an unsignificant risk, which is far less than the risk caused by the fossil-fuelled alternatives

  15. Amino acid profiles and presumptive nutritional assessment of single-cell protein from certain lactobacilli.

    Science.gov (United States)

    Erdman, M D; Bergen, W G; Reddy, C A

    1977-04-01

    The amino acid profiles, modified essential amino acid (MEAA) indexes, and in vitro pepsin digestibilities were determined for single-cell protein (SCP) from certain industrially important lactobacilli. For the three parameters examined, substantial differences were seen between different Lactobacillus species and between strains with a given species. SCP from all of the lactobacilli examined appeared relatively high in MEAA indexes and pepsin digestibility. SCP from L. acidophilus 3205 and L. fermenti 3954 had the highest MEAA indexes, whereas L. bulgaricus 2217 and L. thermophilus 3863 had the highest percentage of digestible crude protein. SCP from L. plantarum strains had the lowest MEAA indexes. The essential amino acid compositions of SCP from different lactobacilli appear comparable to that of Food and Agriculture Organization reference protein and SCP from other sources.

  16. Preliminary performance assessment strategy for single-shell tank waste disposal

    International Nuclear Information System (INIS)

    Sonnichsen, J.C. Jr.

    1991-10-01

    The disposal of the waste stored in single-shell tanks at the Hanford Site is recognized as a major environmental concern. A comprehensive program has been initiated to evaluate the various alternatives available for disposal of these wastes. Theses wastes will be disposed of in a manner consistent with applicable laws and regulations. Long-term waste isolation is one measure of performance that will be used for purposes of selection. The performance of each disposal alternative will be simulated using numerical models. Contained herein is a discussion of the strategy that has and continues to evolve to establish a general analytical framework to evaluate this performance. This general framework will be used to construct individual models of each waste disposal alternative selected for purposes of evaluation. 30 refs., 3 figs

  17. The contribution of single photon emission computed tomography in the clinical assessment of Alzheimer type dementia

    International Nuclear Information System (INIS)

    Boudousq, V.; Collombier, L.; Kotzki, P.O.

    1999-01-01

    Interest of brain single-photon emission computed tomography to support clinical diagnosis of Alzheimer-type dementia is now established. Numerous studies have reported a decreased perfusion in the association cortex of the parietal lobe and the posterior temporal regions. In patients with mild cognitive complaints, the presence of focal hypoperfusion may increase substantially the probability of the disease. In addition, emission tomography emerges as a helpful tool in situation in which there is diagnostic doubt. In this case, the presence of temporo-parietal perfusion deficit associated with hippocampal atrophy on MRI or X-ray computed tomography contributes to diagnostic accuracy. However, some studies suggest that emission tomography may be useful for preclinical prediction of Alzheimer's disease and to predict cognitive decline. (author)

  18. Comparative assessment of single-dose and fractionated boron neutron capture therapy

    International Nuclear Information System (INIS)

    Coderre, J.A.; Micca, P.L.; Fisher, C.D.

    1995-01-01

    The effects of fractionating boron neutron capture therapy (BNCT) were evaluated in the intracerebral rat 9L gliosarcoma and rat spinal cord models using the Brookhaven Medical Research Reactor (BMRR) thermal neutron beam. The amino acid analog p-boronophenylalanine (BPA) was administered prior to each exposure to the thermal neutron beam. The total physical absorbed dose to the tumor during BNCT using BPA was 91% high-linear energy transfer (LET) radiation. Two tumor doses of 5.2 Gy spaced 48 h apart (n = 14) or three tumor doses of 5.2 Gy, each separated by 48 h (n = 10), produced 50 and 60% long-term (>1 year) survivors, respectively. The outcome of neither the two nor the three fractions of radiation was statistically different from that of the corresponding single-fraction group. In the rat spinal cord, the ED 50 for radiation myelopathy (as indicated by limb paralysis within 7 months) after exposure to the thermal beam alone was 13.6 ± 0.4 Gy. Dividing the beam-only irradiation into two or four consecutive daily fractions increased the ED 50 to 14.7 ± 0.2 Gy and 15.5 ± 0.4 Gy, respectively. Thermal neutron irradiation in the presence of BPA resulted in an ED 50 for myelopathy of 13.8 ± 0.6 Gy after a single fraction and 14.9 ± 0.9 Gy after two fractions. An increase in the number of fractions to four resulted in an ED 50 of 14.3 ± 0.6 Gy. The total physical absorbed dose to the blood in the vasculature of the spinal cord during BNCT using BPA was 80% high-LET radiation. It was observed that fractionation was of minor significance in the amelioration of damage to the normal central nervous system in the rat after boron neutron capture irradiation. 30 refs., 5 figs., 3 tabs

  19. Assessment of nitrification potential in ground water using short term, single-well injection experiments.

    Science.gov (United States)

    Smith, R L; Baumgartner, L K; Miller, D N; Repert, D A; Böhlke, J K

    2006-01-01

    Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 microM) and ammonium (19 to 625 microM) and appeared to be a potentially active zone for nitrification. The tests were conducted by injecting a tracer solution (ambient ground water + added constituents) into selected locations within the gradients using multilevel samplers. After injection, the tracers moved by natural ground water flow and were sampled with time from the injection port. Rates of nitrification were determined from changes in nitrate and nitrite concentration relative to bromide. Initial tests were conducted with (15)N-enriched ammonium; subsequent tests examined the effect of adding ammonium, nitrite, or oxygen above background concentrations and of adding difluoromethane, a nitrification inhibitor. In situ net nitrate production exceeded net nitrite production by 3- to 6- fold and production rates of both decreased in the presence of difluoromethane. Nitrification rates were 0.02-0.28 mumol (L aquifer)(-1) h(-1) with in situ oxygen concentrations and up to 0.81 mumol (L aquifer)(-1) h(-1) with non-limiting substrate concentrations. Geochemical considerations indicate that the rates derived from single-well injection tests yielded overestimates of in situ rates, possibly because the injections promoted small-scale mixing within a transport-limited reaction zone. Nonetheless, these tests were useful for characterizing ground water nitrification in situ and for comparing potential rates of activity when the tracer cloud included non-limiting ammonium and oxygen concentrations.

  20. Assessment of nitrification potential in ground water using short term, single-well injection experiments

    Science.gov (United States)

    Smith, R.L.; Baumgartner, L.K.; Miller, D.N.; Repert, D.A.; Böhlke, J.K.

    2006-01-01

    Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 μM) and ammonium (19 to 625 μM) and appeared to be a potentially active zone for nitrification. The tests were conducted by injecting a tracer solution (ambient ground water + added constituents) into selected locations within the gradients using multilevel samplers. After injection, the tracers moved by natural ground water flow and were sampled with time from the injection port. Rates of nitrification were determined from changes in nitrate and nitrite concentration relative to bromide. Initial tests were conducted with 15N-enriched ammonium; subsequent tests examined the effect of adding ammonium, nitrite, or oxygen above background concentrations and of adding difluoromethane, a nitrification inhibitor. In situ net nitrate production exceeded net nitrite production by 3- to 6- fold and production rates of both decreased in the presence of difluoromethane. Nitrification rates were 0.02–0.28 μmol (L aquifer)−1 h−1 with in situ oxygen concentrations and up to 0.81 μmol (L aquifer)−1 h−1 with non-limiting substrate concentrations. Geochemical considerations indicate that the rates derived from single-well injection tests yielded overestimates of in situ rates, possibly because the injections promoted small-scale mixing within a transport-limited reaction zone. Nonetheless, these tests were useful for characterizing ground water nitrification in situ and for comparing potential rates of activity when the tracer cloud included non-limiting ammonium and oxygen concentrations.

  1. Assessing the Nonequilibrium Thermodynamics in a Quenched Quantum Many-Body System via Single Projective Measurements

    Science.gov (United States)

    Fusco, L.; Pigeon, S.; Apollaro, T. J. G.; Xuereb, A.; Mazzola, L.; Campisi, M.; Ferraro, A.; Paternostro, M.; De Chiara, G.

    2014-07-01

    We analyze the nature of the statistics of the work done on or by a quantum many-body system brought out of equilibrium. We show that, for the sudden quench and for an initial state that commutes with the initial Hamiltonian, it is possible to retrieve the whole nonequilibrium thermodynamics via single projective measurements of observables. We highlight, in a physically clear way, the qualitative implications for the statistics of work coming from considering processes described by operators that either commute or do not commute with the unperturbed Hamiltonian of a given system. We consider a quantum many-body system and derive an expression that allows us to give a physical interpretation, for a thermal initial state, to all of the cumulants of the work in the case of quenched operators commuting with the unperturbed Hamiltonian. In the commuting case, the observables that we need to measure have an intuitive physical meaning. Conversely, in the noncommuting case, we show that, although it is possible to operate fully within the single-measurement framework irrespectively of the size of the quench, some difficulties are faced in providing a clear-cut physical interpretation to the cumulants. This circumstance makes the study of the physics of the system nontrivial and highlights the nonintuitive phenomenology of the emergence of thermodynamics from the fully quantum microscopic description. We illustrate our ideas with the example of the Ising model in a transverse field showing the interesting behavior of the high-order statistical moments of the work distribution for a generic thermal state and linking them to the critical nature of the model itself.

  2. Single-well interference slug tests to assess the vertical hydraulic conductivity of unconsolidated aquifers

    Science.gov (United States)

    Paradis, Daniel; Lefebvre, René

    2013-01-01

    SummaryMeaningful understanding of flow and solute transport in general requires the knowledge of hydraulic conductivity and its anisotropy. Various field methods allow the measurement of the horizontal component (Kh), but vertical hydraulic conductivity (Kv) is rarely measured, for lack of practical field tests. This paper proposes vertical interference slug tests, an adaptation of inter-well interference slug tests to a single well, for the efficient field measurement of Kv. The test is carried out in a single well between a stress and an observation interval that are vertically isolated with a three-packer assembly. An instantaneous pressure pulse is induced in the stress interval and resulting drawdowns are recorded in both the stress and the observation intervals. In a proof-of-concept field study, 12 vertical interference tests were carried out sequentially along a fully-screened well across a moderately heterogeneous and highly anisotropic aquifer made up of littoral silts and sands. A direct-push method was used to install the well, which was completed without sand-pack to allow the natural collapse of sediments in the thin annular space around the screen. Direct-push wells allow the measurement of in situ hydraulic properties of sediments and minimize well construction interferences with hydraulic tests. Drawdowns measured in stress and observation intervals of multiple tests were simultaneously inverted numerically to reconstruct heterogeneous profiles of Kh, hydraulic conductivity anisotropy (Kv/Kh), and specific storage (Ss). Results were validated by comparison of observed versus predicted drawdowns and with field and laboratory measurements of Kh and Kv made along the tested well. Results indicate that the profile of Kv values obtained with vertical interference slug tests follows a similar pattern with depth than the profile with lab measurements made with a permeameter on soil samples collected in the same intervals as the interference tests, which

  3. Differential item functioning of the UWES-17 in South Africa

    Directory of Open Access Journals (Sweden)

    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.

  4. Obtaining a Proportional Allocation by Deleting Items

    NARCIS (Netherlands)

    Dorn, B.; de Haan, R.; Schlotter, I.; Röthe, J.

    2017-01-01

    We consider the following control problem on fair allocation of indivisible goods. Given a set I of items and a set of agents, each having strict linear preference over the items, we ask for a minimum subset of the items whose deletion guarantees the existence of a proportional allocation in the

  5. A Balance Sheet for Educational Item Banking.

    Science.gov (United States)

    Hiscox, Michael D.

    Educational item banking presents observers with a considerable paradox. The development of test items from scratch is viewed as wasteful, a luxury in times of declining resources. On the other hand, item banking has failed to become a mature technology despite large amounts of money and the efforts of talented professionals. The question of which…

  6. Clinical value of single versus composite provocative clinical tests in the assessment of painful shoulder.

    Science.gov (United States)

    Salaffi, Fausto; Ciapetti, Alessandro; Carotti, Marina; Gasparini, Stefania; Filippucci, Emilio; Grassi, Walter

    2010-04-01

    The aims of the present study were to investigate the clinical value of the provocative clinical tests and propose a composite index for the assessment of painful shoulder, using ultrasonography (US) as reference method. Two hundred three patients with painful shoulder underwent both clinical and US evaluations. The physical examination was carried out performing the Hawkins, Jobe, Patte, Gerber, and Speed tests. Each test was included in a composite index namely, SNAPSHOT (Simple Numeric Assessment of Pain by SHOulder Tests). The US examination was performed by a rheumatologist experienced in US and blinded to clinical findings. Sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratio of each clinical test were calculated. The receiver operating characteristic (ROC) curve analysis was used to assess the performance of the composite SNAPSHOT index. Sensitivity was low for the clinical diagnosis of all shoulder abnormalities. The highest sensitivity and smallest negative likelihood ratio were found for the Hawkins (63.88% and 0.50%) and Patte (62.21% and 0.52%) tests. Specificity was good for Speed (76.33%), Gerber (75.42%), and Patte (74.20%) tests. Patte and Speed tests were the most accurate (71.12% and 66.41%, respectively). The calculated area under the ROC curve related to the SNAPSHOT composite index was 0.881 +/- 0.026. With an optimal cut-off point of 3, the sensitivity and specificity were 75.8% and 87.5%, respectively. The results of the present study showed that SNAPSHOT is a feasible, informative and quantitative composite index for the assessment of painful shoulder in the clinical setting.

  7. Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brian B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lin, Yashen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gevorgian, Vahan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Purba, Victor [University of Minnesota; Dhople, Sairaj [University of Minnesota

    2017-09-28

    From the inception of power systems, synchronous machines have acted as the foundation of large-scale electrical infrastructures and their physical properties have formed the cornerstone of system operations. However, power electronics interfaces are playing a growing role as they are the primary interface for several types of renewable energy sources and storage technologies. As the role of power electronics in systems continues to grow, it is crucial to investigate the properties of bulk power systems in low inertia settings. In this paper, we assess the properties of coupled machine-inverter systems by studying an elementary system comprised of a synchronous generator, three-phase inverter, and a load. Furthermore, the inverter model is formulated such that its power rating can be scaled continuously across power levels while preserving its closed-loop response. Accordingly, the properties of the machine-inverter system can be assessed for varying ratios of machine-to-inverter power ratings and, hence, differing levels of inertia. After linearizing the model and assessing its eigenvalues, we show that system stability is highly dependent on the interaction between the inverter current controller and machine exciter, thus uncovering a key concern with mixed machine-inverter systems and motivating the need for next-generation grid-stabilizing inverter controls.

  8. Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brian B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lin, Yashen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gevorgian, Vahan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Purba, Victor [University of Minnesota; Dhople, Sairaj [University of Minnesota

    2017-11-16

    Synchronous machines have traditionally acted as the foundation of large-scale electrical infrastructures and their physical properties have formed the cornerstone of system operations. However, with the increased integration of distributed renewable resources and energy-storage technologies, there is a need to systematically acknowledge the dynamics of power-electronics inverters - the primary energy-conversion interface in such systems - in all aspects of modeling, analysis, and control of the bulk power network. In this paper, we assess the properties of coupled machine-inverter systems by studying an elementary system comprised of a synchronous generator, three-phase inverter, and a load. The inverter model is formulated such that its power rating can be scaled continuously across power levels while preserving its closed-loop response. Accordingly, the properties of the machine-inverter system can be assessed for varying ratios of machine-to-inverter power ratings. After linearizing the model and assessing its eigenvalues, we show that system stability is highly dependent on the inverter current controller and machine exciter, thus uncovering a key concern with mixed machine-inverter systems and motivating the need for next-generation grid-stabilizing inverter controls.

  9. Assessing motor, visual and language function using a single 5-minute fMRI paradigm: three birds with one stone.

    Science.gov (United States)

    Fiori, Simona; Zendler, Carolin; Hauser, Till-Karsten; Lidzba, Karen; Wilke, Marko

    2018-02-26

    Clinical functional Magnetic Resonance Imaging (fMRI) requires inferences on localization of major brain functions at the individual subject level. We hypothesized that a single "triple use" task would satisfy sensitivity and reliability requirements for successfully assessing the motor, visual and language domain in this context. This was tested here by the application in a group of healthy adults, assessing sensitivity and reliability at the individual subject level, separately for each domain.Our "triple use" task consisted of 2 conditions (condition 1, assessing motor and visual domain, and condition 2, assessing the language domain), serving mutually as active/control. We included 20 healthy adult subjects. Random effect analyses showed activation in primary motor, visual and language regions, as expected. Less expected regions were activated both for the motor and visual domains. Further, reliability of primary activation patterns was very high across individual subjects, with activation seen in 70-100% of subjects in primary motor, visual, and left-lateralized language regions.These findings suggest the "triple use" task to be reliable at the individual subject's level to assess motor, visual and language domains in the clinical fMRI context. Benefits of such an approach include shortening of acquisition time, simplicity of the task for each domain, and using a visual stimulus. Following establishment of reliability in adults, the task may also be a valuable addition in the pediatric clinical fMRI context, where each of these factors is of high relevance.

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

    Science.gov (United States)

    van Nispen, Ruth M A; Knol, Dirk L; Langelaan, Maaike; van Rens, Ger H M B

    2011-09-02

    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). 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-X(2)-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. 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. 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.

  11. New technologies for item monitoring

    International Nuclear Information System (INIS)

    Abbott, J.A.; Waddoups, I.G.

    1993-12-01

    This report responds to the Department of Energy's request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence ampersand Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet)

  12. Presenting a 4-Item Spiritual Well-Being Index (4-ISWBI

    Directory of Open Access Journals (Sweden)

    John Fisher

    2017-09-01

    Full Text Available Spiritual well-being is perceived to be reflected in the quality of relationships that people have in four areas, namely with God, others, nature, and self. Many spiritual well-being questionnaires exist, but not many provide an adequate assessment of these four relationships. As part of a survey of parental perceptions of holistic early childhood education in kindergartens in Hong Kong, 1383 parents and 165 teachers, from 22 kindergartens, completed a written survey questionnaire which helped to investigate the potential for a single question with four parts to provide a valid and reliable measure for spiritual well-being. Face, content, and construct validity were confirmed, together with Cronbach’s alpha providing a test for reliability. Similarity of findings from regression analysis of items in the 4-ISWBI with domains of spiritual well-being in the 20-item SHALOM, as well as partial discrimination by gender, reinforce the validity of the 4-ISWBI as a sound indicator of spiritual well-being and its four domains. In brief, the 4-Item Spiritual Well-Being Index (4-ISWBI promises to be a handy instrument to aid researchers looking for a convenient, concise, coherent indicator, but not an exhaustive measure, of spiritual well-being.

  13. The Body Appreciation Scale-2: item refinement and psychometric evaluation.

    Science.gov (United States)

    Tylka, Tracy L; Wood-Barcalow, Nichole L

    2015-01-01

    Considered a positive body image measure, the 13-item Body Appreciation Scale (BAS; Avalos, Tylka, & Wood-Barcalow, 2005) assesses individuals' acceptance of, favorable opinions toward, and respect for their bodies. While the BAS has accrued psychometric support, we improved it by rewording certain BAS items (to eliminate sex-specific versions and body dissatisfaction-based language) and developing additional items based on positive body image research. In three studies, we examined the reworded, newly developed, and retained items to determine their psychometric properties among college and online community (Amazon Mechanical Turk) samples of 820 women and 767 men. After exploratory factor analysis, we retained 10 items (five original BAS items). Confirmatory factor analysis upheld the BAS-2's unidimensionality and invariance across sex and sample type. Its internal consistency, test-retest reliability, and construct (convergent, incremental, and discriminant) validity were supported. The BAS-2 is a psychometrically sound positive body image measure applicable for research and clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. 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.

  15. Assessment of single-turn extraction for a superconducting separated-sector cyclotron

    Directory of Open Access Journals (Sweden)

    J.-W. Kim

    1999-04-01

    Full Text Available We have studied the beam dynamics in a high field separated-sector cyclotron to establish conditions required to achieve single-turn extraction. Extraction efficiency above 99% is aimed to avoid beam-induced damages. A sufficient last-turn separation and a preservation of beam quality throughout the acceleration are the prerequisites. The last-turn separation can be enhanced with the orbital precession induced by an off-centering injection as in existent lower field separated-sector cyclotrons. The beam qualities, on the other hand, are affected by the resonances traversed or approached during the acceleration. Acceleration of light nuclei to the energies of 300–400 MeV/u was especially disturbing because of the broadening of radial beamwidth upon crossing the ν_{r}=3/2 resonance. Tolerance to the third harmonic gradient field, which causes the resonance in lowest order, is set to be 0.1 G/cm. The integer resonance ν_{z}=1 can be avoided with a proper design of the yoke. The longitudinal space charge forces were also investigated to estimate the intensity limits determined by the energy spreads of beam assuming simplified charge distributions. Moreover, beam preparations for injection matching are described in view of reducing the beam losses into the extraction elements.

  16. Performance and risk assessment of subsurface barriers for single-shell tank waste retrieval

    Energy Technology Data Exchange (ETDEWEB)

    Bazinet, G.D.; Cruse, J.M.; Hampsten, K.L. [Westinghouse Hanford Co., Richland, WA (United States); Treat, R.L.

    1995-02-01

    Subsurface barriers are among various alternatives under evaluation to mitigate the threat of leakage from the Hanford Site`s 149 single-shell high-level radioactive waste tanks. The Tank Waste Remediation System (TWRS) division of Westinghouse Hanford Company is conducting this evaluation of subsurface barriers and other alternatives, focusing on risk and cost as performance measures. A number of alternative retrieval/closure approaches were evaluated in terms of risks (carcinogenic and toxicological) to a postulated maximally exposed individual. In addition, worker and accident risks were evaluated and factors developed for each alternative on a relative basis. The work performed to date indicates the use of subsurface barriers may potentially reduce public risk by limiting contamination of groundwater below the Hanford Site; however, the cost in terms of actual funding and in elevated worker risk is significant. The analyses also assume certain performance levels for technologies that have not been demonstrated in field conditions similar to Hanford Site tank farms. The evaluations summarized herein are being used to support a decision by representatives of the US Department of Energy, Richland Operations Office, the Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA) regarding potential further development of subsurface barrier technology.

  17. Performance and risk assessment of subsurface barriers for single-shell tank waste retrieval

    International Nuclear Information System (INIS)

    Bazinet, G.D.; Cruse, J.M.; Hampsten, K.L.; Treat, R.L.

    1995-02-01

    Subsurface barriers are among various alternatives under evaluation to mitigate the threat of leakage from the Hanford Site's 149 single-shell high-level radioactive waste tanks. The Tank Waste Remediation System (TWRS) division of Westinghouse Hanford Company is conducting this evaluation of subsurface barriers and other alternatives, focusing on risk and cost as performance measures. A number of alternative retrieval/closure approaches were evaluated in terms of risks (carcinogenic and toxicological) to a postulated maximally exposed individual. In addition, worker and accident risks were evaluated and factors developed for each alternative on a relative basis. The work performed to date indicates the use of subsurface barriers may potentially reduce public risk by limiting contamination of groundwater below the Hanford Site; however, the cost in terms of actual funding and in elevated worker risk is significant. The analyses also assume certain performance levels for technologies that have not been demonstrated in field conditions similar to Hanford Site tank farms. The evaluations summarized herein are being used to support a decision by representatives of the US Department of Energy, Richland Operations Office, the Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA) regarding potential further development of subsurface barrier technology

  18. Elastographic assessment of liver fibrosis in children: A prospective single center experience

    Energy Technology Data Exchange (ETDEWEB)

    Marginean, Cristina Oana, E-mail: marginean.oana@gmail.com [Department of Paediatrics, University of Medicine and Pharmacy of Tg. Mures (Romania); Marginean, Claudiu, E-mail: marginean.claudiu@gmail.com [Department of Obstetrics and Gynecology, University of Medicine and Pharmacy of Tg. Mures (Romania)

    2012-08-15

    Background: The assessment of liver damage in various disease states relies on a combination of clinical findings, biochemical parameters and invasive tests such as liver biopsy. The ultrasound elastography has emerged as a potential alternative test, providing quantifiable information on the elasticity/stiffness of the examined-tissues. We assessed the performance of ultrasound elastography using real-time Acoustic Radiation Force Imaging (ARFI) technology in evaluating the degree of liver fibrosis in children with and without liver disease. Methods: Children aged 0-18 years, hospitalized in the Emergency Clinical County Hospital Tg. Mures, Romania, between September 15, 2010 and January 15, 2011, were eligible for the study. Four groups were recruited as follow: patients with liver disease in the setting of various malignant disorders, children with non-malignant liver disease, overweight and obese children and healthy controls. The liver tissue elasticity was assessed in each individual using Shear Wave Velocity (SWV). Biochemical tests included transaminase levels. 19 children with chronic liver disease underwent biopsies. SWV was measured globally and separately for the liver-segments 1 and 8. Correlations between the SWV and laboratory test were established using non-parametric Spearman correlation test. Results: A total of 103 children underwent liver ultrasound elastographic assessments. Of these, 39 had malignancies, 19 had various chronic liver diseases, 13 had nonalcoholic fatty liver disease (NAFLD), and 32 were healthy controls. The transaminase values differed significantly between children with liver diseases and controls. In normal controls SWV values in the 1st segment were significantly lower compared to those in the in 8th segment of the liver (p = 0.0216). In the group with hepatic steatosis, the SWV values were statistically higher compared to those in healthy controls. Positive statistical correlations have been established between AST and SWV

  19. Elastographic assessment of liver fibrosis in children: A prospective single center experience

    International Nuclear Information System (INIS)

    Marginean, Cristina Oana; Marginean, Claudiu

    2012-01-01

    Background: The assessment of liver damage in various disease states relies on a combination of clinical findings, biochemical parameters and invasive tests such as liver biopsy. The ultrasound elastography has emerged as a potential alternative test, providing quantifiable information on the elasticity/stiffness of the examined-tissues. We assessed the performance of ultrasound elastography using real-time Acoustic Radiation Force Imaging (ARFI) technology in evaluating the degree of liver fibrosis in children with and without liver disease. Methods: Children aged 0–18 years, hospitalized in the Emergency Clinical County Hospital Tg. Mures, Romania, between September 15, 2010 and January 15, 2011, were eligible for the study. Four groups were recruited as follow: patients with liver disease in the setting of various malignant disorders, children with non-malignant liver disease, overweight and obese children and healthy controls. The liver tissue elasticity was assessed in each individual using Shear Wave Velocity (SWV). Biochemical tests included transaminase levels. 19 children with chronic liver disease underwent biopsies. SWV was measured globally and separately for the liver-segments 1 and 8. Correlations between the SWV and laboratory test were established using non-parametric Spearman correlation test. Results: A total of 103 children underwent liver ultrasound elastographic assessments. Of these, 39 had malignancies, 19 had various chronic liver diseases, 13 had nonalcoholic fatty liver disease (NAFLD), and 32 were healthy controls. The transaminase values differed significantly between children with liver diseases and controls. In normal controls SWV values in the 1st segment were significantly lower compared to those in the in 8th segment of the liver (p = 0.0216). In the group with hepatic steatosis, the SWV values were statistically higher compared to those in healthy controls. Positive statistical correlations have been established between AST and

  20. A Generalized Logistic Regression Procedure to Detect Differential Item Functioning among Multiple Groups

    Science.gov (United States)

    Magis, David; Raiche, Gilles; Beland, Sebastien; Gerard, Paul

    2011-01-01

    We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence…

  1. Single, repeated dose toxicity and genotoxicity assessment of herb formula KIOM2012H

    Directory of Open Access Journals (Sweden)

    Hwayong Park

    2017-12-01

    Full Text Available Background: Traditional medicine and herbal prescriptions are becoming more popular, and they account for a large share of the world’s healthcare research studies, developments, and market demands. Increasing scientific evidence of the substantive efficacies such as preventive health keeping pharmaceutical materials and dietary supplements can be found elsewhere. Above all, safety should be the critical premise for considering developmental materials such as pharmaceuticals without side effects and toxicity. Methods: The authors formulated KIOM2012H (K2H using four herbs that were reported to have medicinal effects—including anticancer, antiaging, antimicrobial, inflammation, and neuroprotective properties. In order to examine the toxicity, single and repeated dose toxicity, and genotoxicities of bacterial mutation, micronucleus, and chromosomal aberration assays were conducted. Results: All experimental observations and results showed normal findings. Toxicities or abnormal signs were not observed in all experimental assays, including oral administration, animal behavior, clinical findings, and changes in body weight in vivo. In vitro bacterial cultures produced no revertant colonies, and no increased numbers of structural or numerical aberrant metaphases were found in the metaphase chromosomes examined. Moreover, no significant increased frequency of micronucleus was observed in any of the doses used. Overall, no acute toxicity or genotoxicity was found in all analysis parameters in all the assays conducted. Conclusion: Reviewing the results as a whole, K2H extract was regarded as a safe material with no toxicity, and can be applied for the research and development of complementary and alternative medicines with improved efficacy in current therapeutic healthcare, based on traditional medicine and herb resources. Keywords: genotoxicity, herb, toxicity, traditional medicine

  2. Development of six PROMIS pediatrics proxy-report item banks.

    Science.gov (United States)

    Irwin, Debra E; Gross, Heather E; Stucky, Brian D; Thissen, David; DeWitt, Esi Morgan; Lai, Jin Shei; Amtmann, Dagmar; Khastou, Leyla; Varni, James W; DeWalt, Darren A

    2012-02-22

    Pediatric self-report should be considered the standard for measuring patient reported outcomes (PRO) among children. However, circumstances exist when the child is too young, cognitively impaired, or too ill to complete a PRO instrument and a proxy-report is needed. This paper describes the development process including the proxy cognitive interviews and large-field-test survey methods and sample characteristics employed to produce item parameters for the Patient Reported Outcomes Measurement Information System (PROMIS) pediatric proxy-report item banks. The PROMIS pediatric self-report items were converted into proxy-report items before undergoing cognitive interviews. These items covered six domains (physical function, emotional distress, social peer relationships, fatigue, pain interference, and asthma impact). Caregivers (n = 25) of children ages of 5 and 17 years provided qualitative feedback on proxy-report items to assess any major issues with these items. From May 2008 to March 2009, the large-scale survey enrolled children ages 8-17 years to complete the self-report version and caregivers to complete the proxy-report version of the survey (n = 1548 dyads). Caregivers of children ages 5 to 7 years completed the proxy report survey (n = 432). In addition, caregivers completed other proxy instruments, PedsQL™ 4.0 Generic Core Scales Parent Proxy-Report version, PedsQL™ Asthma Module Parent Proxy-Report version, and KIDSCREEN Parent-Proxy-52. Item content was well understood by proxies and did not require item revisions but some proxies clearly noted that determining an answer on behalf of their child was difficult for some items. Dyads and caregivers of children ages 5-17 years old were enrolled in the large-scale testing. The majority were female (85%), married (70%), Caucasian (64%) and had at least a high school education (94%). Approximately 50% had children with a chronic health condition, primarily asthma, which was diagnosed or treated within 6

  3. Losing Items in the Psychogeriatric Nursing Home

    Directory of Open Access Journals (Sweden)

    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.

  4. Bile Gastritis Following Laparoscopic Single Anastomosis Gastric Bypass: Pilot Study to Assess Significance of Bilirubin Level in Gastric Aspirate.

    Science.gov (United States)

    Shenouda, Michael M; Harb, Shady ElGhazaly; Mikhail, Sameh A A; Mokhtar, Sherif M; Osman, Ayman M A; Wassef, Arsany T S; Rizkallah, Nayer N H; Milad, Nader M; Anis, Shady E; Nabil, Tamer Mohamed; Zaki, Nader Sh; Halepian, Antoine

    2018-02-01

    Laparoscopic single anastomosis gastric bypass (SAGB) is increasingly performed for morbidly obese patients. This pilot study aims primarily at evaluating the incidence of bile gastritis after SAGB. The occurrence of reflux oesophagitis and reflux symptoms were also assessed. This study included 20 patients having no reflux symptoms. All patients underwent a SAGB as a primary bariatric procedure by a single surgeon. Patients included consented to have an upper GI endoscopy done at 6 months postoperatively. Gastric aspirate was sent for bilirubin level assessment. Gastric and esophageal biopsies were submitted for histopathology and campylobacter-like organism (CLO) test. In our study, the rate of bile gastritis was 30%. In 18 patients, the level of bilirubin in gastric aspirate seems to be related to the degree of mucosal inflammation. The remaining two patients had microscopic moderate to severe gastritis with normal aspirate bilirubin level. Two patients with bilirubin level in aspirate more than 20 mg/dl had severe oesophagitis, gastritis with erosions, and metaplasia. Relationship between bilirubin level and histopathological findings of gastric biopsy examination was statistically significant with a P value of 0.001. The incidence of bile gastritis in this cohort is higher than reported in the literature, and this may be worrying. The correlation between endoscopic findings and patients' symptoms is poor. Bilirubin level and pH in aspirate might be useful tools to confirm alkaline reflux. Its level might help to choose candidates for revision surgery after SAGB. This needs further validation with larger sample size.

  5. Epilogue: Reading Comprehension Is Not a Single Ability-Implications for Assessment and Instruction.

    Science.gov (United States)

    Kamhi, Alan G; Catts, Hugh W

    2017-04-20

    In this epilogue, we review the 4 response articles and highlight the implications of a multidimensional view of reading for the assessment and instruction of reading comprehension. We reiterate the problems with standardized tests of reading comprehension and discuss the advantages and disadvantages of recently developed authentic tests of reading comprehension. In the "Instruction" section, we review the benefits and limitations of strategy instruction and highlight suggestions from the response articles to improve content and language knowledge. We argue that the only compelling reason to administer a standardized test of reading comprehension is when these tests are necessary to qualify students for special education services. Instruction should be focused on content knowledge, language knowledge, and specific task and learning requirements. This instruction may entail the use of comprehension strategies, particularly those that are specific to the task and focus on integrating new knowledge with prior knowledge.

  6. Comparison of single- and double-assessor scoring designs for the assessment of accomplished teaching.

    Science.gov (United States)

    Engelhard, George; Myford, Carol M

    2009-01-01

    This article is based on a more extensive research report (Engelhard, Myford and Cline, 2000) prepared for the National Board for Professional Teaching Standards (NBPTS) concerning the Early Childhood/Generalist and Middle Childhood/Generalist assessment systems. The report is available from the Educational Testing Service (ETS). An earlier version of the article was presented at the American Educational Research Association Conference in New Orleans in 2000. We would like to acknowledge the helpful advice of Mike Linacre regarding the use of the FACETS computer program and the assistance of Fred Cline in analyzing these data. The material contained in this article is based on work supported by the NBPTS. Any opinions, findings, conclusions, and recommendations expressed herein are those of the authors and do not necessarily reflect the views of the NBPTS, Emory University, ETS, or the University of Illinois at Chicago.

  7. Improving assessment of daily energy expenditure by identifying types of physical activity with a single accelerometer.

    Science.gov (United States)

    Bonomi, A G; Plasqui, G; Goris, A H C; Westerterp, K R

    2009-09-01

    Accelerometers are often used to quantify the acceleration of the body in arbitrary units (counts) to measure physical activity (PA) and to estimate energy expenditure. The present study investigated whether the identification of types of PA with one accelerometer could improve the estimation of energy expenditure compared with activity counts. Total energy expenditure (TEE) of 15 subjects was measured with the use of double-labeled water. The physical activity level (PAL) was derived by dividing TEE by sleeping metabolic rate. Simultaneously, PA was measured with one accelerometer. Accelerometer output was processed to calculate activity counts per day (AC(D)) and to determine the daily duration of six types of common activities identified with a classification tree model. A daily metabolic value (MET(D)) was calculated as mean of the MET compendium value of each activity type weighed by the daily duration. TEE was predicted by AC(D) and body weight and by AC(D) and fat-free mass, with a standard error of estimate (SEE) of 1.47 MJ/day, and 1.2 MJ/day, respectively. The replacement in these models of AC(D) with MET(D) increased the explained variation in TEE by 9%, decreasing SEE by 0.14 MJ/day and 0.18 MJ/day, respectively. The correlation between PAL and MET(D) (R(2) = 51%) was higher than that between PAL and AC(D) (R(2) = 46%). We conclude that identification of activity types combined with MET intensity values improves the assessment of energy expenditure compared with activity counts. Future studies could develop models to objectively assess activity type and intensity to further increase accuracy of the energy expenditure estimation.

  8. Quantitative Analysis of Complex Multiple-Choice Items in Science Technology and Society: Item Scaling

    Directory of Open Access Journals (Sweden)

    Ángel Vázquez Alonso

    2005-05-01

    Full Text Available The scarce attention to assessment and evaluation in science education research has been especially harmful for Science-Technology-Society (STS education, due to the dialectic, tentative, value-laden, and controversial nature of most STS topics. To overcome the methodological pitfalls of the STS assessment instruments used in the past, an empirically developed instrument (VOSTS, Views on Science-Technology-Society have been suggested. Some methodological proposals, namely the multiple response models and the computing of a global attitudinal index, were suggested to improve the item implementation. The final step of these methodological proposals requires the categorization of STS statements. This paper describes the process of categorization through a scaling procedure ruled by a panel of experts, acting as judges, according to the body of knowledge from history, epistemology, and sociology of science. The statement categorization allows for the sound foundation of STS items, which is useful in educational assessment and science education research, and may also increase teachers’ self-confidence in the development of the STS curriculum for science classrooms.

  9. Investigating factors affecting students’ performance to PISA Science items

    Directory of Open Access Journals (Sweden)

    V. Hatzinikita

    2008-01-01

    Full Text Available The present paper aims to investigate, on the one hand, the extent to which PISA Science items validly assess the knowledge and skills of 15 year-old Greek students, while, on the other hand, to examine the effect of the following factors: student’s gender, scientific processes and contexts (situations on the students’ performance in these PISA items. The research used paper-and-pencil test with published PISA Science items, conducted individual semi-structured interviews with 15 year-old students and finally marked the students’ responses, according to the PISA marking guide. Τhe basic finding resulting from the data analysis is that the paper-and-pencil test with the PISA Science items does not tend, unlike the interview, to effectively record the Greek students’ Science knowledge and skills. Moreover, the analysis revealed that the performance of students in the PISA Science items (paper-and-pencil test and interview tend to be independent of the student’s gender and depend on the context in which the knowledge and processes are assessed. Additionally, the possible correlation between the students’ performance and the factor of scientific processes seems to depend on the setting in which the students provide their responses (paper-and-pencil test or interview.

  10. An item analysis of the Conditional Reasoning Test of Aggression.

    Science.gov (United States)

    DeSimone, Justin A; James, Lawrence R

    2015-11-01

    This manuscript uses item response theory (IRT) to estimate item characteristics of the Conditional Reasoning Test of Aggression (CRT-A). Using a sample size of 5,511 respondents, the present analysis provides an accurate assessment of the capability of the CRT-A to measure latent aggression. The one-parameter logistic (1PL) model, two-parameter logistic (2PL) model, and three-parameter logistic (3PL) model are compared before the item analysis. Results suggest that the 2PL model is the most appropriate dichotomous IRT model for describing the item characteristics of the CRT-A. Potential multdimensionality in the CRT-A is also examined. Results suggest that CRT-A items work as theoretically intended, with the probability of selecting an aggressive response increasing with latent trait levels. Information curves indicate that the CRT-A is best suited for use with individuals who are high on latent aggression. Exploratory analyses include an examination of polytomous IRT models and DIF comparing student and employee respondents. The results have implications for future research using the CRT-A as well as the identification of populations appropriate for measurement using this assessment tool. (c) 2015 APA, all rights reserved).

  11. RIM: A Random Item Mixture Model to Detect Differential Item Functioning

    Science.gov (United States)

    Frederickx, Sofie; Tuerlinckx, Francis; De Boeck, Paul; Magis, David

    2010-01-01

    In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is assumed for the item difficulties such that the…

  12. Detecting Differential Item Discrimination (DID) and the Consequences of Ignoring DID in Multilevel Item Response Models

    Science.gov (United States)

    Lee, Woo-yeol; Cho, Sun-Joo

    2017-01-01

    Cross-level invariance in a multilevel item response model can be investigated by testing whether the within-level item discriminations are equal to the between-level item discriminations. Testing the cross-level invariance assumption is important to understand constructs in multilevel data. However, in most multilevel item response model…

  13. Prevalence of single nucleotide polymorphism among 27 diverse alfalfa genotypes as assessed by transcriptome sequencing

    Directory of Open Access Journals (Sweden)

    Li Xuehui

    2012-10-01

    Full Text Available Abstract Background Alfalfa, a perennial, outcrossing species, is a widely planted forage legume producing highly nutritious biomass. Currently, improvement of cultivated alfalfa mainly relies on recurrent phenotypic selection. Marker assisted breeding strategies can enhance alfalfa improvement efforts, particularly if many genome-wide markers are available. Transcriptome sequencing enables efficient high-throughput discovery of single nucleotide polymorphism (SNP markers for a complex polyploid species. Result The transcriptomes of 27 alfalfa genotypes, including elite breeding genotypes, parents of mapping populations, and unimproved wild genotypes, were sequenced using an Illumina Genome Analyzer IIx. De novo assembly of quality-filtered 72-bp reads generated 25,183 contigs with a total length of 26.8 Mbp and an average length of 1,065 bp, with an average read depth of 55.9-fold for each genotype. Overall, 21,954 (87.2% of the 25,183 contigs represented 14,878 unique protein accessions. Gene ontology (GO analysis suggested that a broad diversity of genes was represented in the resulting sequences. The realignment of individual reads to the contigs enabled the detection of 872,384 SNPs and 31,760 InDels. High resolution melting (HRM analysis was used to validate 91% of 192 putative SNPs identified by sequencing. Both allelic variants at about 95% of SNP sites identified among five wild, unimproved genotypes are still present in cultivated alfalfa, and all four US breeding programs also contain a high proportion of these SNPs. Thus, little evidence exists among this dataset for loss of significant DNA sequence diversity from either domestication or breeding of alfalfa. Structure analysis indicated that individuals from the subspecies falcata, the diploid subspecies caerulea, and the tetraploid subspecies sativa (cultivated tetraploid alfalfa were clearly separated. Conclusion We used transcriptome sequencing to discover large numbers of SNPs

  14. Lipoprotein(a Is the Best Single Marker in Assessing Unstable Angina Pectoris

    Directory of Open Access Journals (Sweden)

    Vidosava B. Djordjević

    2011-01-01

    Full Text Available This study evaluated whether statin therapy changed a diagnostic validity of lipid and inflammatory markers in ischemic heart disease (IHD patients. Levels of lipids, lipoproteins, apolipoproteins, inflammatory markers, and atherogenic indexes were determined in 49 apparently healthy men and women, 82 patients having stable angina pectoris (SAP, 80 patients with unstable angina (USAP, and 106 patients with acute ST-elevation myocardial infarction (STEMI treated or not treated with statins. Diagnostic accuracy of markers was determined by ROC curve analysis. Significantly lower apoA-I in all statin-treated groups and significantly higher apoB in statin-treated STEMI group compared to non-statin-treated groups were observed. CRP showed the best ROC characteristics in the assessment of STEMI patients. Lp(a is better in the evaluation of SAP and USAP patients, considering that Lp(a showed the highest area under the curve (AUC. Regarding atherogenic indexes, the highest AUC in SAP group was obtained for TG/apoB and in USAP and STEMI patients for TG/HDL-c. Statins lowered total cholesterol, LDL-c, and TG but fail to normalize apoA-I in patients with IHD.

  15. The 10-item Remembered Relationship with Parents (RRP10) scale

    DEFF Research Database (Denmark)

    Denollet, Johan; Smolderen, Kim G E; van den Broek, Krista C

    2007-01-01

    Dysfunctional parenting styles are associated with poor mental and physical health. The 10-item Remembered Relationship with Parents (RRP(10)) scale retrospectively assesses Alienation (dysfunctional communication and intimacy) and Control (overprotection by parents), with an emphasis...... on deficiencies in empathic parenting. We examined the 2-factor structure of the RRP(10) and its relationship with adult depression....

  16. Professor-Student Rapport Scale: Six Items Predict Student Outcomes

    Science.gov (United States)

    Wilson, Janie H.; Ryan, Rebecca G.

    2013-01-01

    Rapport between students and teachers leads to numerous positive student outcomes, including attitudes toward the teacher and course, student motivation, and perceived learning. The recent development of a Professor-Student Rapport scale offers assessment of this construct. However, a Cronbach's [alpha] of 0.96 indicated item redundancy, and the…

  17. Small-Item Contact Test Method, FY11 Release

    Science.gov (United States)

    2012-07-01

    developmental and operational testing (DT/OT) activities , technology readiness assessments (TRA) to determine technology readiness level (TRL...or gas phase ( fumigants , including aerosols). decontamination process: The process of making any person, object, or area safe by absorbing...item. • For vaporous decontaminants: injection rate, flow rate, fumigant concentration, temperature, and relative humidity. • For liquid

  18. Beneficial effect of coronary artery bypass grafting as assessed by quantitative gated single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hida, Satoshi; Chikamori, Taishiro; Hirayama, Tetsuzo; Usui, Yasuhiro; Yanagisawa, Hidefumi; Morishima, Takayuki; Ishimaru, Shin; Yamashina, Akira [Tokyo Medical Coll. (Japan)

    2003-06-01

    The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50{+-}12{yields}53{+-}11%; p<0.05). In 107 revascularized territories, the average regional reversible defect score (0.8{+-}0.5{yields}0.2{+-}0.3; p<0.0001), average regional perfusion score at rest (0.6{+-}0.6{yields}0.3{+-}0.4; p<0.0001), average regional wall motion score (0.9{+-}0.7{yields}0.7{+-}0.5; p<0.05), and end-diastolic wall thickness (8.1{+-}1.3{yields}8.6{+-}1.5 mm; p<0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5{+-}0.7{yields}0.2{+-}0.5; p<0.03), average regional wall motion score (0.8{+-}1.1{yields}0.5{+-}1.0; p<0.03) and end-diastolic wall thickness (8.0{+-}1.4{yields}9.1{+-}2.0 mm; p<0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT. (author)

  19. Area-aggregated assessments of perceived environmental attributes may overcome single-source bias in studies of green environments and health: results from a cross-sectional survey in southern Sweden

    Directory of Open Access Journals (Sweden)

    Wadbro John

    2011-01-01

    Full Text Available Abstract Background Most studies assessing health effects of neighborhood characteristics either use self-reports or objective assessments of the environment, the latter often based on Geographical Information Systems (GIS. While objective measures require detailed landscape data, self-assessments may yield confounded results. In this study we demonstrate how self-assessments of green neighborhood environments aggregated to narrow area units may serve as an appealing compromise between objective measures and individual self-assessments. Methods The study uses cross-sectional data (N = 24,847 from a public health survey conducted in the county of Scania, southern Sweden, in 2008 and validates the Scania Green Score (SGS, a new index comprising five self-reported green neighborhood qualities (Culture, Lush, Serene, Spacious and Wild. The same qualities were also assessed objectively using landscape data and GIS. A multilevel (ecometric model was used to aggregate individual self-reports to assessments of perceived green environmental attributes for areas of 1,000 square meters. We assessed convergent and concurrent validity for self-assessments of the five items separately and for the sum score, individually and area-aggregated. Results Correlations between the index scores based on self-assessments and the corresponding objective assessments were clearly present, indicating convergent validity, but the agreement was low. The correlation was even more evident for the area-aggregated SGS. All three scores (individual SGS, area-aggregated SGS and GIS index score were associated with neighborhood satisfaction, indicating concurrent validity. However, while individual SGS was associated with vitality, this association was not present for aggregated SGS and the GIS-index score, suggesting confounding (single-source bias when individual SGS was used. Conclusions Perceived and objectively assessed qualities of the green neighborhood environment correlate

  20. Assessment of mixed-layer height estimation from single-wavelength ceilometer profiles

    Science.gov (United States)

    Knepp, Travis N.; Szykman, James J.; Long, Russell; Duvall, Rachelle M.; Krug, Jonathan; Beaver, Melinda; Cavender, Kevin; Kronmiller, Keith; Wheeler, Michael; Delgado, Ruben; Hoff, Raymond; Berkoff, Timothy; Olson, Erik; Clark, Richard; Wolfe, Daniel; Van Gilst, David; Neil, Doreen

    2017-10-01

    Differing boundary/mixed-layer height measurement methods were assessed in moderately polluted and clean environments, with a focus on the Vaisala CL51 ceilometer. This intercomparison was performed as part of ongoing measurements at the Chemistry And Physics of the Atmospheric Boundary Layer Experiment (CAPABLE) site in Hampton, Virginia and during the 2014 Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) field campaign that took place in and around Denver, Colorado. We analyzed CL51 data that were collected via two different methods (BLView software, which applied correction factors, and simple terminal emulation logging) to determine the impact of data collection methodology. Further, we evaluated the STRucture of the ATmosphere (STRAT) algorithm as an open-source alternative to BLView (note that the current work presents an evaluation of the BLView and STRAT algorithms and does not intend to act as a validation of either). Filtering criteria were defined according to the change in mixed-layer height (MLH) distributions for each instrument and algorithm and were applied throughout the analysis to remove high-frequency fluctuations from the MLH retrievals. Of primary interest was determining how the different data-collection methodologies and algorithms compare to each other and to radiosonde-derived boundary-layer heights when deployed as part of a larger instrument network. We determined that data-collection methodology is not as important as the processing algorithm and that much of the algorithm differences might be driven by impacts of local meteorology and precipitation events that pose algorithm difficulties. The results of this study show that a common processing algorithm is necessary for light detection and ranging (lidar)-based MLH intercomparisons and ceilometer-network operation, and that sonde-derived boundary layer heights are higher (10-15 % at midday) than lidar

  1. Assessment of mixed-layer height estimation from single-wavelength ceilometer profiles

    Directory of Open Access Journals (Sweden)

    T. N. Knepp

    2017-10-01

    Full Text Available Differing boundary/mixed-layer height measurement methods were assessed in moderately polluted and clean environments, with a focus on the Vaisala CL51 ceilometer. This intercomparison was performed as part of ongoing measurements at the Chemistry And Physics of the Atmospheric Boundary Layer Experiment (CAPABLE site in Hampton, Virginia and during the 2014 Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ field campaign that took place in and around Denver, Colorado. We analyzed CL51 data that were collected via two different methods (BLView software, which applied correction factors, and simple terminal emulation logging to determine the impact of data collection methodology. Further, we evaluated the STRucture of the ATmosphere (STRAT algorithm as an open-source alternative to BLView (note that the current work presents an evaluation of the BLView and STRAT algorithms and does not intend to act as a validation of either. Filtering criteria were defined according to the change in mixed-layer height (MLH distributions for each instrument and algorithm and were applied throughout the analysis to remove high-frequency fluctuations from the MLH retrievals. Of primary interest was determining how the different data-collection methodologies and algorithms compare to each other and to radiosonde-derived boundary-layer heights when deployed as part of a larger instrument network. We determined that data-collection methodology is not as important as the processing algorithm and that much of the algorithm differences might be driven by impacts of local meteorology and precipitation events that pose algorithm difficulties. The results of this study show that a common processing algorithm is necessary for light detection and ranging (lidar-based MLH intercomparisons and ceilometer-network operation, and that sonde-derived boundary layer heights are higher (10–15 % at

  2. Benefits Assessment for Single-Airport Tactical Runway Configuration Management Tool (TRCM)

    Science.gov (United States)

    Oseguera-Lohr, Rosa; Phojanamonogkolkij, Nipa; Lohr, Gary W.

    2015-01-01

    -level or generic in nature (not focusing on specific airports), and benefits were aggregated for the entire NAS, with relatively low fidelity simulation of SORM functions and aircraft trajectories. For SORM research, a more detailed benefits assessment of RCM and CADRS for specific airports or metroplexes is needed.

  3. Psychometric aspects of item mapping for criterion-referenced interpretation and bookmark standard setting.

    Science.gov (United States)

    Huynh, Huynh

    2010-01-01

    Locating an item on an achievement continuum (item mapping) is well-established in technical work for educational/psychological assessment. Applications of item mapping may be found in criterion-referenced (CR) testing (or scale anchoring, Beaton and Allen, 1992; Huynh, 1994, 1998a, 2000a, 2000b, 2006), computer-assisted testing, test form assembly, and in standard setting methods based on ordered test booklets. These methods include the bookmark standard setting originally used for the CTB/TerraNova tests (Lewis, Mitzel, Green, and Patz, 1999), the item descriptor process (Ferrara, Perie, and Johnson, 2002) and a similar process described by Wang (2003) for multiple-choice licensure and certification examinations. While item response theory (IRT) models such as the Rasch and two-parameter logistic (2PL) models traditionally place a binary item at its location, Huynh has argued in the cited papers that such mapping may not be appropriate in selecting items for CR interpretation and scale anchoring.

  4. Application of Benchmark Examples to Assess the Single and Mixed-Mode Static Delamination Propagation Capabilities in ANSYS

    Science.gov (United States)

    Krueger, Ronald

    2012-01-01

    The application of benchmark examples for the assessment of quasi-static delamination propagation capabilities is demonstrated for ANSYS. The examples are independent of the analysis software used and allow the assessment of the automated delamination propagation in commercial finite element codes based on the virtual crack closure technique (VCCT). The examples selected are based on two-dimensional finite element models of Double Cantilever Beam (DCB), End-Notched Flexure (ENF), Mixed-Mode Bending (MMB) and Single Leg Bending (SLB) specimens. First, the quasi-static benchmark examples were recreated for each specimen using the current implementation of VCCT in ANSYS . Second, the delamination was allowed to propagate under quasi-static loading from its initial location using the automated procedure implemented in the finite element software. Third, the load-displacement relationship from a propagation analysis and the benchmark results were compared, and good agreement could be achieved by selecting the appropriate input parameters. The benchmarking procedure proved valuable by highlighting the issues associated with choosing the input parameters of the particular implementation. Overall the results are encouraging, but further assessment for three-dimensional solid models is required.

  5. Quantification of a single score (1+) in the Modified Ashworth Scale (MAS), a clinical assessment of spasticity.

    Science.gov (United States)

    Ewoldt, Jourdan K; Lazzaro, Emily C; Roth, Elliot J; Suresh, Nina L

    2016-08-01

    The Modified Ashworth Scale (MAS) is an assessment that is often used by clinicians to grade spasticity in the affected limbs of stroke survivors. The MAS is a function of the angle at which the clinician perceives a resistance to stretch and/or a `catch' during a passive joint rotation. The qualitative nature of the assessment in combination with the low resolution of the scale could result in varied grouping of spastic patients, even for a single score. The objective of this pilot study was to develop a method for the quantification of the MAS, which could provide greater resolution and could eventually guide better informed therapeutic interventions. The MAS assessment at the elbow joint for four stroke survivors with the same clinical MAS score of 1+ was performed by a clinician and quantified using signals from surface electromyography (EMG) and an electrogoniometer. The subjects were tested on both the affected and contralateral upper limbs. The findings from this study show a varied set of signal outputs across four stroke survivors, all graded at 1+. The quantification provides insight as to the mechanisms underlying the passive resistance.

  6. Single-compound and cumulative risk assessment of mycotoxins present in breakfast cereals consumed by children from Lisbon region, Portugal.

    Science.gov (United States)

    Assunção, Ricardo; Vasco, Elsa; Nunes, Baltazar; Loureiro, Susana; Martins, Carla; Alvito, Paula

    2015-12-01

    Humans can be exposed to multiple chemicals, but current risk assessment is usually carried out on one chemical at a time. Mycotoxins are commonly found in a variety of foods including those intended to consumption by children namely breakfast cereals. The present study aims to perform, the risk assessment of single and multiple mycotoxins present in breakfast cereals consumed by children (1-3 years old) from Lisbon region, Portugal. Daily exposure of children to ochratoxin A, fumonisins and trichothecenes showed no health risks to the children population considering individual mycotoxins, while exposure to aflatoxin B1 (AFB1) suggested a potential health concern for the high percentiles of intake (P90, P95 and P99). The combined exposure to fumonisins and trichothecenes are not expected to be of health concern. The combined margin of exposure (MoET) for the aflatoxins group could constitute a potential health concern and AFB1 was the main contributor for MoET. Legal limits and control strategies regarding the presence of multiple mycotoxins in foodstuffs is an urgent need. To the best of our knowledge, this is the first time a cumulative risk assessment was performed on multiple mycotoxins present in breakfast cereals consumed by children. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. International Semiotics: Item Difficulty and the Complexity of Science Item Illustrations in the PISA-2009 International Test Comparison

    Science.gov (United States)

    Solano-Flores, Guillermo; Wang, Chao; Shade, Chelsey

    2016-01-01

    We examined multimodality (the representation of information in multiple semiotic modes) in the context of international test comparisons. Using Program of International Student Assessment (PISA)-2009 data, we examined the correlation of the difficulty of science items and the complexity of their illustrations. We observed statistically…

  8. Net and Global Differential Item Functioning in PISA Polytomously Scored Science Items: Application of the Differential Step Functioning Framework

    Science.gov (United States)

    Akour, Mutasem; Sabah, Saed; Hammouri, Hind

    2015-01-01

    The purpose of this study was to apply two types of Differential Item Functioning (DIF), net and global DIF, as well as the framework of Differential Step Functioning (DSF) to real testing data to investigate measurement invariance related to test language. Data from the Program for International Student Assessment (PISA)-2006 polytomously scored…

  9. Automated single-trial assessment of laser-evoked potentials as an objective functional diagnostic tool for the nociceptive system.

    Science.gov (United States)

    Hatem, S M; Hu, L; Ragé, M; Gierasimowicz, A; Plaghki, L; Bouhassira, D; Attal, N; Iannetti, G D; Mouraux, A

    2012-12-01

    To assess the clinical usefulness of an automated analysis of event-related potentials (ERPs). Nociceptive laser-evoked potentials (LEPs) and non-nociceptive somatosensory electrically-evoked potentials (SEPs) were recorded in 37 patients with syringomyelia and 21 controls. LEP and SEP peak amplitudes and latencies were estimated using a single-trial automated approach based on time-frequency wavelet filtering and multiple linear regression, as well as a conventional approach based on visual inspection. The amplitudes and latencies of normal and abnormal LEP and SEP peaks were identified reliably using both approaches, with similar sensitivity and specificity. Because the automated approach provided an unbiased solution to account for average waveforms where no ERP could be identified visually, it revealed significant differences between patients and controls that were not revealed using the visual approach. The automated analysis of ERPs characterized reliably and objectively LEP and SEP waveforms in patients. The automated single-trial analysis can be used to characterize normal and abnormal ERPs with a similar sensitivity and specificity as visual inspection. While this does not justify its use in a routine clinical setting, the technique could be useful to avoid observer-dependent biases in clinical research. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Personality in remitted major depressive disorder with single and recurrent episodes assessed with the Temperament and Character Inventory.

    Science.gov (United States)

    Teraishi, Toshiya; Hori, Hiroaki; Sasayama, Daimei; Matsuo, Junko; Ogawa, Shintaro; Ishida, Ikki; Nagashima, Anna; Kinoshita, Yukiko; Ota, Miho; Hattori, Kotaro; Higuchi, Teruhiko; Kunugi, Hiroshi

    2015-01-01

    Previous studies consistently reported increased harm avoidance (HA) assessed with the Temperament and Character Inventory (TCI) in patients with major depressive disorder (MDD). However, such findings may have been related with depression severity and number of depressive episodes. The aims of the present study were twofold: to examine TCI personality profile in remitted MDD (DSM-IV) patients and to compare TCI personality between MDD patients with single episode (SGL-MDD) and those with recurrent episodes (REC-MDD) in order to elucidate personality profile associated with recurrence. TCI was administered to 86 outpatients with remitted SGL-MDD (12 male and 17 female patients; mean age 43.2 ± 12.1 years) and REC-MDD (26 male and 31 female patients; 40.3 ± 11.6 years), and 529 healthy controls (225 men and 304 women; 43.4 ± 15.5 years), matched for age, sex and education years. Logistic regression analyses were performed in which single/recurrent episodes of depression were the dependent variable and age, sex, age of onset, family history of psychiatric disease and TCI scores were entered as possible predictors. The remitted MDD patients had significantly higher scores on HA (P personality profile between remitted MDD patients and controls, and between remitted REC-MDD and SGL-MDD patients, suggesting that they are trait markers. HA and fatigability might be useful to assess risk for recurrence of depression. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  11. Financial incentives for smoking cessation in pregnancy: a single-arm intervention study assessing cessation and gaming

    Science.gov (United States)

    Ierfino, Diana; Mantzari, Eleni; Hirst, Julie; Jones, Tina; Aveyard, Paul; Marteau, Theresa M

    2015-01-01

    Aims Financial incentives were the single most effective intervention for smoking cessation in pregnancy in a recent Cochrane Review, but based on a few small trials in the United States using only 7-day point prevalence measures of cessation. This study estimates (a) prolonged cessation in an unselected population of English pregnant smokers who are offered financial incentives for quitting and (b) ‘gaming’, i.e. false reporting of smoking status to enter the scheme or gain an incentive. Design Single-arm intervention study Setting Antenatal clinic and community Participants A total of 239 pregnant smokers enrolled into the financial incentive scheme, attending for maternity care at one hospital in an area of high deprivation in England over a 42-week period. Measurements Smoking cessation at delivery and 6 months postpartum, assessed using salivary cotinine; gaming assessed using urinary and salivary cotinine at enrolment, 28 and 36 weeks gestation, and 2 days and 6 months postpartum. Findings Thirty-nine per cent (239 of 615) of smokers were enrolled into the scheme, 60% (143 of 239) of whom made a quit attempt. Of those enrolled, 20% [48 of 239; 95% confidence interval (CI) = 14.9%, 25.1%] were quit at delivery and 10% (25 of 239; 95% CI = 6.2%, 13.8%) at 6 months postpartum. There was no evidence that women gamed to enter the scheme, but evidence that 4% (10 of 239) of those enrolled gamed on one or more occasions to gain vouchers. Conclusions Enrolment on an incentive scheme in an unselected English cohort of pregnant smokers was associated with prolonged cessation rates comparable to those reported in US trials. Rates of gaming were arguably insufficiently high to invalidate the use of such schemes. PMID:25727238

  12. A single product perishing inventory model with demand interaction ...

    African Journals Online (AJOL)

    The paper describes a single perishing product inventory model in which items deteriorate in two phases and then perish. An independent demand takes place at constant rates for items in both phases. A demand for an item in Phase I not satisfied may be satisfied by an item in Phase II, based on a probability measure.

  13. Assessment of left ventricular function with single breath-hold highly accelerated cine MRI combined with guide-point modeling

    International Nuclear Information System (INIS)

    Heilmaier, Christina; Nassenstein, Kai; Nielles-Vallespin, Sonia; Zuehlsdorff, Sven; Hunold, Peter; Barkhausen, Joerg

    2010-01-01

    Purpose: To prospectively assess the performance of highly accelerated cine MRI in multi-orientations combined with a new guide-point modeling post-processing technique (GPM approach) for assessment of left ventricular (LV) function compared to the standard summation of slices method based on a stack of short axis views (SoS approach). Materials and methods: 33 consecutive patients were examined on a 1.5 T scanner with a standard steady state free precession (SSFP) sequence (TR, 3.0 ms; TE, 1.5 m; flip angle (FA), 60 o ; acceleration factor (AF), 2) analyzed with the SoS method and a highly accelerated, single breath-hold temporal parallel acquisition SSFP sequence (TR, 4.6 ms; TE, 1.1 ms; AF, 3) post-processed with the GPM method. LV function values were measured by two independent readers with different experience in cardiac MRI and compared by using the paired t-test and F-test. Inter- and intraobserver agreements were calculated using Bland-Altman-Plots. Results: Mean acquisition and post-processing time was significantly shorter with the GPM approach (15 s/3 min versus 360 s/6 min). For all LV function parameters interobserver agreement between the experienced and non-experienced reader was significantly improved when the GPM approach was used. However, end-diastolic and end-systolic volumes were larger for the GPM technique when compared to the SoS method (P 0.121). In both readers and for all parameters variances did not differ significantly (P ≥ 0.409) and the two approaches showed an excellent linear correlation (r > 0.951). Conclusion: Due to its accurate, fast and reproducible assessment of LV function parameters highly accelerated MRI combined with the GPM technique may become the technique of first choice for assessment of LV function in clinical routine.

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

    Science.gov (United States)

    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.

  15. Trends in Sodium Content of Menu Items in Large Chain Restaurants in the U.S.

    Science.gov (United States)

    Wolfson, Julia A; Moran, Alyssa J; Jarlenski, Marian P; Bleich, Sara N

    2018-01-01

    Consuming too much sodium is associated with increased risk for cardiovascular disease, and restaurant foods are a primary source of sodium. This study assessed recent trends in sodium content of menu items in U.S. chain restaurants. Data from 21,557 menu items in 66 top-earning chain restaurants available from 2012 to 2016 were obtained from the MenuStat project and analyzed in 2017. Generalized linear models were used to examine changes in calorie-adjusted, per-item sodium content of menu items offered in all years (2012-2016) and items offered in 2012 only compared with items newly introduced in 2013, 2014, 2015, and 2016. Overall, calorie-adjusted sodium content in newly introduced menu items declined by 104 mg from 2012 to 2016 (prestaurant type; sodium content, particularly for main course items, was high. Sodium declined by 83 mg in fast food restaurants, 19 mg in fast casual restaurants, and 163 mg in full service restaurants. Sodium in appetizer and side items newly introduced in 2016 increased by 266 mg compared with items on the menu in 2012 only (prestaurants. However, sodium content of core and new menu items remain high, and reductions are inconsistent across menu categories and restaurant types. Copyright © 2018 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  16. Using Automated Processes to Generate Test Items And Their Associated Solutions and Rationales to Support Formative Feedback

    Directory of Open Access Journals (Sweden)

    Mark Gierl

    2015-08-01

    Full Text Available Automatic item generation is the process of using item models to produce assessment tasks using computer technology. An item model is similar to a template that highlights the elements in the task that must be manipulated to produce new items. The purpose of our study is to describe an innovative method for generating large numbers of diverse and heterogeneous items along with their solutions and associated rationales to support formative feedback. We demonstrate the method by generating items in two diverse content areas, mathematics and nonverbal reasoning

  17. The PROMIS Physical Function item bank was calibrated to a standardized metric and shown to improve measurement efficiency

    DEFF Research Database (Denmark)

    Rose, Matthias; Bjørner, Jakob; Gandek, Barbara

    2014-01-01

    OBJECTIVE: To document the development and psychometric evaluation of the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) item bank and static instruments. STUDY DESIGN AND SETTING: The items were evaluated using qualitative and quantitative methods. A total...... of 16,065 adults answered item subsets (n>2,200/item) on the Internet, with oversampling of the chronically ill. Classical test and item response theory methods were used to evaluate 149 PROMIS PF items plus 10 Short Form-36 and 20 Health Assessment Questionnaire-Disability Index items. A graded...... response model was used to estimate item parameters, which were normed to a mean of 50 (standard deviation [SD]=10) in a US general population sample. RESULTS: The final bank consists of 124 PROMIS items covering upper, central, and lower extremity functions and instrumental activities of daily living...

  18. Longitudinal investigation of source memory reveals different developmental trajectories for item memory and binding

    OpenAIRE

    Riggins, Tracy

    2013-01-01

    The present study used a cohort-sequential design to examine developmental changes in children's ability to bind items in memory during early and middle childhood. Three cohorts of children (aged 4, 6, or 8 years) were followed longitudinally for three years. Each year, children completed a source memory paradigm assessing memory for items and binding. Results suggest linear increases in memory for individual items (facts or sources) between 4 and 10 years of age, but that memory for correct ...

  19. A method of assessment of sustainability of social and labor relations of a city-forming enterprise and a single-industry town

    Directory of Open Access Journals (Sweden)

    Roshina Irina

    2016-01-01

    Full Text Available In this article we consider one of the tools for managing a single-industry town – a method of assessment of its social and labor relations sustainability. We describe a mathematical model of calculating the integrated index and give instant assessment examples.

  20. Is the Assessment of 5 Meters of Gait with a Single Body-Fixed-Sensor Enough to Recognize Idiopathic Parkinson's Disease-Associated Gait?

    NARCIS (Netherlands)

    Micó-Amigo, M E; Kingma, I; Faber, G S; Kunikoshi, A.; van Uem, J. M T; van Lummel, R C; Maetzler, W.; van Dieën, J H

    Quantitative assessment of gait in patients with Parkinson's disease (PD) is an important step in addressing motor symptoms and improving clinical management. Based on the assessment of only 5 meters of gait with a single body-fixed-sensor placed on the lower back, this study presents a method for

  1. 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.)

  2. Modeling rule-based item generation

    NARCIS (Netherlands)

    Geerlings, Hanneke; Glas, Cornelis A.W.; van der Linden, Willem J.

    2011-01-01

    An application of a hierarchical IRT model for items in families generated through the application of different combinations of design rules is discussed. Within the families, the items are assumed to differ only in surface features. The parameters of the model are estimated in a Bayesian framework,

  3. Bayesian Estimation of Item Response Curves.

    Science.gov (United States)

    Tsutakawa, Robert K.; Lin, Hsin Ying

    1986-01-01

    Item response curves for a set of binary responses are studied from a Bayesian viewpoint of estimating the item parameters. For the two-parameter logistic model with normally distributed ability, restricted bivariate beta priors are used to illustrate the computation of the posterior mode via the EM algorithm. (Author/LMO)

  4. Binomial test models and item difficulty

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1979-01-01

    In choosing a binomial test model, it is important to know exactly what conditions are imposed on item difficulty. In this paper these conditions are examined for both a deterministic and a stochastic conception of item responses. It appears that they are more restrictive than is generally

  5. Item Information in the Rasch Model

    NARCIS (Netherlands)

    Engelen, Ron J.H.; van der Linden, Willem J.; Oosterloo, Sebe J.

    1988-01-01

    Fisher's information measure for the item difficulty parameter in the Rasch model and its marginal and conditional formulations are investigated. It is shown that expected item information in the unconditional model equals information in the marginal model, provided the assumption of sampling

  6. Development of an item bank and computer adaptive test for role functioning.

    Science.gov (United States)

    Anatchkova, Milena D; Rose, Matthias; Ware, John E; Bjorner, Jakob B

    2012-11-01

    Role functioning (RF) is a key component of health and well-being and an important outcome in health research. The aim of this study was to develop an item bank to measure impact of health on role functioning. A set of different instruments including 75 newly developed items asking about the impact of health on role functioning was completed by 2,500 participants. Established item response theory methods were used to develop an item bank based on the generalized partial credit model. Comparison of group mean bank scores of participants with different self-reported general health status and chronic conditions was used to test the external validity of the bank. After excluding items that did not meet established requirements, the final item bank consisted of a total of 64 items covering three areas of role functioning (family, social, and occupational). Slopes in the bank ranged between .93 and 4.37; the mean threshold range was -1.09 to -2.25. Item bank-based scores were significantly different for participants with and without chronic conditions and with different levels of self-reported general health. An item bank assessing health impact on RF across three content areas has been successfully developed. The bank can be used for development of short forms or computerized adaptive tests to be applied in the assessment of role functioning as one of the common denominators across applications of generic health assessment.

  7. Performance of Thallium-201 Electrocardiography-gated Myocardial Perfusion Single Photon Emission Computed Tomography to Assess Left Ventricular Function

    Directory of Open Access Journals (Sweden)

    Guang-Uei Hung

    2005-05-01

    Full Text Available This study evaluated the performance of gated single photon emission computed tomography (SPECT with thallium-201 (201Tl in assessing left ventricular ejection fraction (LVEF, end-diastolic volume (EDV, and end-systolic volume (ESV in Taiwanese by determining repeatability and correlation with two-dimensional (2D echocardiography. A total of 18 patients underwent two sequential gated SPECT acquisitions within 30 minutes in the resting state to assess repeatability. Another 28 patients who underwent gated SPECT and 2D echocardiography within 7 days were included for comparison. The two sequential measurements were well correlated with respect to LVEF, EDV, and ESV (r = 0.97, 0.95, and 0.97, respectively, all p < 0.0001. Bland-Altman analysis revealed that two standard deviations of the absolute difference between the two sequential measurements for LVEF, EDV, and ESV were 6.4%, 16.8 mL, and 8.6 mL, respectively. For LVEF, EDV, and ESV, correlations between redistribution 201Tl-gated SPECT and echocardiography were also excellent (all r = 0.83, p < 0.0001. LVEF was similar with 201Tl-gated SPECT and echocardiography, but EDV and ESV were significantly higher with echocardiography (p < 0.05. Our study revealed that 201Tl-gated SPECT has high repeatability and excellent correlation with echocardiography for the assessment of LVEF and volumes in Taiwanese. These results support the clinical application of gated SPECT in routine 201Tl myocardial perfusion imaging in Taiwanese.

  8. Comparison of single- or multifrequency bioelectrical impedance analysis and spectroscopy for assessment of appendicular skeletal muscle in the elderly.

    Science.gov (United States)

    Yamada, Yosuke; Watanabe, Yuya; Ikenaga, Masahiro; Yokoyama, Keiichi; Yoshida, Tsukasa; Morimoto, Taketoshi; Kimura, Misaka

    2013-09-01

    Bioelectrical impedance analysis (BIA) is used to assess skeletal muscle mass, although its application in the elderly has not been fully established. Several BIA modalities are available: single-frequency BIA (SFBIA), multifrequency BIA (MFBIA), and bioelectrical impedance spectroscopy (BIS). The aim of this study was to examine the difference between SFBIA, MFBIA, and BIS for assessment of appendicular skeletal muscle strength in the elderly. A total of 405 elderly (74.2 ± 5.0 yr) individuals were recruited. Grip strength and isometric knee extension strength were measured. Segmental SFBIA, MFBIA, and BIS were measured for the arms and upper legs. Bioelectrical impedance indexes were calculated by squared segment length divided by impedance (L2/Z). Impedance at 5 and 50 kHz (Z5 and Z50) was used for SFBIA. Impedance of the intracellular component was calculated from MFBIA (Z250-5) and BIS (RICW). Correlation coefficients between knee extension strength and L2/Z5, L2/Z50, L2/RICW, and L2/Z250-5 of the upper legs were 0.661, 0.705, 0.790, and 0.808, respectively (P < 0.001). Correlation coefficients were significantly greater for MFBIA and BIS than SFBIA. Receiver operating characteristic curves showed that L2/Z250-5 and L2/RICW had significantly larger areas under the curve for the diagnosis of muscle weakness compared with L2/Z5 and L2/Z50. Very similar results were observed for grip strength. Our findings suggest that MFBIA and BIS are better methods than SFBIA for assessing skeletal muscle strength in the elderly.

  9. Development of a lack of appetite item bank for computer-adaptive testing (CAT).

    Science.gov (United States)

    Thamsborg, Lise Holst; Petersen, Morten Aa; Aaronson, Neil K; Chie, Wei-Chu; Costantini, Anna; Holzner, Bernhard; Verdonck-de Leeuw, Irma M; Young, Teresa; Groenvold, Mogens

    2015-06-01

    A significant proportion of oncological patients experiences lack of appetite. Precise measurement is relevant to improve the management of lack of appetite. The so-called computer-adaptive test (CAT) allows for adaptation of the questionnaire to the individual patient, thereby optimizing measurement precision. The EORTC Quality of Life Group is developing a CAT version of the widely used EORTC QLQ-C30 questionnaire. Here, we report on the development of the lack of appetite CAT. The EORTC approach to CAT development comprises four phases: literature search, operationalization, pre-testing, and field testing. Phases 1-3 are described in this paper. First, a list of items was retrieved from the literature. This was refined, deleting redundant and irrelevant items. Next, new items fitting the "QLQ-C30 item style" were created. These were evaluated by international samples of experts and cancer patients. The literature search generated a list of 146 items. After a comprehensive item selection procedure, the list was reduced to 24 items. These formed the basis for 21 new items fitting the QLQ-C30 item style. Expert evaluations (n = 10) and patient interviews (n = 49) reduced the list to 12 lack of appetite items. Phases 1-3 resulted in 12 lack of appetite candidate items. Based on a field testing (phase 4), the psychometric characteristics of the items will be assessed and the final item bank will be generated. This CAT item bank is expected to provide precise and efficient measurement of lack of appetite while still being backward compatible to the original QLQ-C30 scale.

  10. An Item Analysis and Validity Investigation of Bender Visual Motor Gestalt Test Score Items

    Science.gov (United States)

    Lambert, Nadine M.

    1971-01-01

    This investigation attempted to demonstrate the utility of standard item analysis procedures for selecting the most reliable and valid items for scoring Bender Visual Motor Gestalt Test test records. (Author)

  11. Assessing the Test Information Function and Differential Item Functioning for the "TOEFL Junior"® Standard Test. Research Report. ETS RR-13-17. "TOEFL Junior"® Research Report. TOEFL JR-01

    Science.gov (United States)

    Young, John W.; Morgan, Rick; Rybinski, Paul; Steinberg, Jonathan; Wang, Yuan

    2013-01-01

    The "TOEFL Junior"® Standard Test is an assessment that measures the degree to which middle school-aged students learning English as a second language have attained proficiency in the academic and social English skills representative of English-medium instructional environments. The assessment measures skills in three areas: listening…

  12. An improved labeling strategy enables automated detection of single-virus fusion and assessment of HIV-1 protease activity in single virions.

    Science.gov (United States)

    Sood, Chetan; Francis, Ashwanth C; Desai, Tanay M; Melikyan, Gregory B

    2017-12-08

    Enveloped viruses transfer their genomes into host cells by fusing their membrane to that of the cell. To visualize single-virus fusion in living cells, researchers take advantage of the proteolytic maturation of HIV, type 1 (HIV-1), which can generate free fluorescent proteins within the viral particle. Co-labeling viruses with a content marker and a fluorescently tagged Vpr (a viral core protein) enables detection of single-virus fusions, but a major limitation of this approach is that not all viral particles incorporate both markers. Here we designed a labeling strategy based on the bifunctional mCherry-2xCL-YFP-Vpr construct, in which 2xCL denotes a tandem cleavage site for the viral protease. This bifunctional marker was efficiently cleaved during virus maturation, producing free mCherry and the core-associated YFP-Vpr. A nearly perfect colocalization of these two markers in virions and their fixed 1:1 ratio enabled automated detection of single-particle fusion in both fixed and live cells based on loss of the mCherry signal. Furthermore, a drop in FRET efficiency between YFP and mCherry because of cleavage of the bifunctional marker, which manifested as a marked shift in the normalized YFP/mCherry fluorescence ratio, reliably predicted viral protease activity in single virions. This feature could discriminate between the particles containing free mCherry, and therefore likely representing mature viruses, and immature particles whose fusion cannot be detected. In summary, our new labeling strategy offers several advantages compared with previous approaches, including increased reliability and throughput of detection of viral fusion. We anticipate that our method will have significant utility for studying viral fusion and maturation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Assessment of paraspinal muscle hardness in subjects with a mild single scoliosis curve: a preliminary myotonometer study.

    Science.gov (United States)

    Oliva-Pascual-Vaca, Ángel; Heredia-Rizo, Alberto Marcos; Barbosa-Romero, Alejandro; Oliva-Pascual-Vaca, Jesús; Rodríguez-Blanco, Cleofás; Tejero-García, Sergio

    2014-06-01

    The purpose of this study was to evaluate the hardness of the paraspinal muscles in the convexity and concavity of patients with scoliosis curvatures and in the upper trapezius (UT) muscle in subjects with mild idiopathic scoliosis (IS) and to observe the correlation between the myotonometer (MYO) measurements and the value of body mass index (BMI) and the Cobb angle. The sample included 13 patients with a single-curve mild IS (Risser sign ≤ 4) at thoracic, lumbar, or thoracolumbar level (mean Cobb angle of 11.53º). Seven females and 6 males were recruited, with a mean age of 12.84 ± 3.06 (9-18) years. A MYO was used to examine the differences in muscle hardness on both sides of the scoliosis curvature at several points: (a) apex of the curve, (b) upper and lower limits of the curve, and (c) the midpoint between the apex and the upper limit and between the apex and the lower limit. The UT was also explored. Although the MYO recorded lower values in all points on the concave side of the scoliosis, there were no significant differences in the comparison between sides (P > .05). No association was observed between BMI and MYO values, whereas the Cobb angle negatively correlated with muscle hardness only at 2 points on the convex side. The preliminary findings show that, in subjects with a single-curve mild IS, muscular hardness in the UT and paraspinal muscles, as assessed using a MYO, was not found to differ between the concave and the convex sides at different reference levels. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  14. In vitro genotoxic effects of hard metal particles assessed by alkaline single cell gel and elution assays.

    Science.gov (United States)

    Anard, D; Kirsch-Volders, M; Elhajouji, A; Belpaeme, K; Lison, D

    1997-01-01

    Hard metals (WC-Co) are made of a mixture of cobalt metal (Co, 5-10%) and tungsten carbide particles (WC, >80%). Excessive inhalation of WC-Co is associated with the occurrence of different lung diseases including an excess of lung cancers. The elective toxicity of hard metal is based on a physico-chemical interaction between cobalt metal and tungsten carbide particles to produce activated oxygen species. The aim of the present study was to assess the genotoxic activity of hard metal particles as compared with Co and WC alone. In human peripheral lymphocytes incubated with Co or WC-Co, a dose- and time-dependent increased production of DNA single strand breaks (ssb) was evidenced by alkaline single cell gel electrophoresis (SCGE) and modified alkaline elution (AE) assays. Addition of 1 M formate, a hydroxyl radical scavenger, had a protective effect against the production of ssb by both WC-Co or Co alone. On the basis of an equivalent cobalt-content, WC-Co produced significantly more ssb than Co. WC alone did not produce DNA ssb detectable by the AE assay, but results obtained with the SCGE assay may suggest that it either allows some uncoiling of the chromatin loops or induces the formation of slowly migrating fragments. Overall, this in vitro study is the first demonstration of the clastogenic property of cobalt metal-containing dusts. The results are consistent with the implication of an increased production of hydroxyl radicals when Co is mixed with WC particles. The SCGE results also suggest that WC may modify the structure of the chromatin, leading to an increased DNA sensitivity to clastogenic effects. Both mechanisms are not mutually exclusive and may concurrently contribute to the greater clastogenic activity of WC-Co dust. This property of WC-Co particles may account for the excess of lung cancers observed in hard metal workers.

  15. A unified factor-analytic approach to the detection of item and test bias: Illustration with the effect of providing calculators to students with dyscalculia

    Directory of Open Access Journals (Sweden)

    Lee, M. K.

    2016-01-01

    Full Text Available An absence of measurement bias against distinct groups is a prerequisite for the use of a given psychological instrument in scientific research or high-stakes assessment. Factor analysis is the framework explicitly adopted for the identification of such bias when the instrument consists of a multi-test battery, whereas item response theory is employed when the focus narrows to a single test composed of discrete items. Item response theory can be treated as a mild nonlinearization of the standard factor model, and thus the essential unity of bias detection at the two levels merits greater recognition. Here we illustrate the benefits of a unified approach with a real-data example, which comes from a statewide test of mathematics achievement where examinees diagnosed with dyscalculia were accommodated with calculators. We found that items that can be solved by explicit arithmetical computation became easier for the accommodated examinees, but the quantitative magnitude of this differential item functioning (measurement bias was small.

  16. Software Note: Using BILOG for Fixed-Anchor Item Calibration

    Science.gov (United States)

    DeMars, Christine E.; Jurich, Daniel P.

    2012-01-01

    The nonequivalent groups anchor test (NEAT) design is often used to scale item parameters from two different test forms. A subset of items, called the anchor items or common items, are administered as part of both test forms. These items are used to adjust the item calibrations for any differences in the ability distributions of the groups taking…

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

    Science.gov (United States)

    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…

  18. A Regional and Local Item Response Theory Based Test Item Bank System.

    Science.gov (United States)

    Hathaway, Walter; And Others

    This report describes the development, operation, maintenance, and future prospects of the item banks pioneered by the Portland (Oregon) School District. At the time of this report, there were 3,500 mathematics, 2,200 reading, and 2,300 language usage items calibrated under the fixed parameter model of item response theory (IRT) for Grades 3-8.…

  19. 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

  20. RIM: A random item mixture model to detect Differential Item Functioning

    NARCIS (Netherlands)

    Frederickx, S.; Tuerlinckx, T.; de Boeck, P.; Magis, D.

    2010-01-01

    In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is

  1. The Generalized Logit-Linear Item Response Model for Binary-Designed Items

    Science.gov (United States)

    Revuelta, Javier

    2008-01-01

    This paper introduces the generalized logit-linear item response model (GLLIRM), which represents the item-solving process as a series of dichotomous operations or steps. The GLLIRM assumes that the probability function of the item response is a logistic function of a linear composite of basic parameters which describe the operations, and the…

  2. Item Purification in Differential Item Functioning Using Generalized Linear Mixed Models

    Science.gov (United States)

    Liu, Qian

    2011-01-01

    For this dissertation, four item purification procedures were implemented onto the generalized linear mixed model for differential item functioning (DIF) analysis, and the performance of these item purification procedures was investigated through a series of simulations. Among the four procedures, forward and generalized linear mixed model (GLMM)…

  3. 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…

  4. The Predictive Validity of the Beck Depression Inventory Suicide Item.

    Science.gov (United States)

    Green, Kelly L; Brown, Gregory K; Jager-Hyman, Shari; Cha, Jason; Steer, Robert A; Beck, Aaron T

    2015-12-01

    The current study examines the predictive validity of the Beck Depression Inventory (BDI) suicide item for death by suicide and suicide attempts. The study included 2 samples: (1) 5,200 psychiatric outpatients who were evaluated between 1975 and 1995 and followed prospectively for up to 20 years (all psychiatric diagnoses based on DSM-III and DSM-III-R), and (2) 119 patients who, between 2000 and 2004, participated in a randomized controlled trial of outpatient Cognitive Therapy for Suicide Prevention after a suicide attempt and were followed for 18 months (all psychiatric diagnoses based on DSM-IV-TR). All patients completed structured diagnostic interviews, as well as the BDI and Scale for Suicide Ideation. Cox regression models demonstrated that the BDI suicide item significantly predicted both deaths by suicide (Wald χ(2)1 = 35.67; P < .001 [N = 5,200]) and repeat suicide attempts (Wald χ(2)1 = 8.82; P < .01 [N = 119]), with each successive rating on the item conferring greater risk. Using receiver operating characteristic (ROC) curves, optimal cutoff scores of 1 and above for suicide and 2 and above for suicide attempts were identified as providing the best balance between sensitivity and specificity. The BDI suicide item is associated with both risk of repeat suicide attempts and death by suicide. The use of the item as a brief, efficient screen for suicide risk in routine clinical care is recommended. Clinicians would then conduct a comprehensive suicide risk assessment in response to a positive screen. Future research examining the item's performance in other at-risk groups (ie, older adults, adolescents, inpatients, etc) is encouraged. © Copyright 2015 Physicians Postgraduate Press, Inc.

  5. 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.

  6. Dependability and Treatment Sensitivity of Multi-Item Direct Behavior Rating Scales for Interpersonal Peer Conflict

    Science.gov (United States)

    Daniels, Brian; Volpe, Robert J.; Briesch, Amy M.; Gadow, Kenneth D.

    2017-01-01

    Direct behavior rating (DBR) represents a feasible method for monitoring student behavior in the classroom; however, limited work to date has focused on the use of multi-item scales. The purposes of the study were to examine the (a) dependability of data obtained from a multi-item DBR designed to assess peer conflict and (b) treatment sensitivity…

  7. Linguistic Simplification of Mathematics Items: Effects for Language Minority Students in Germany

    Science.gov (United States)

    Haag, Nicole; Heppt, Birgit; Roppelt, Alexander; Stanat, Petra

    2015-01-01

    In large-scale assessment studies, language minority students typically obtain lower test scores in mathematics than native speakers. Although this performance difference was related to the linguistic complexity of test items in some studies, other studies did not find linguistically demanding math items to be disproportionally more difficult for…

  8. Longitudinal Investigation of Source Memory Reveals Different Developmental Trajectories for Item Memory and Binding

    Science.gov (United States)

    Riggins, Tracy

    2014-01-01

    The present study used a cohort-sequential design to examine developmental changes in children's ability to bind items in memory during early and middle childhood. Three cohorts of children (aged 4, 6, or 8 years) were followed longitudinally for 3 years. Each year, children completed a source memory paradigm assessing memory for items and…

  9. The measurement of tritium in Canadian food items

    International Nuclear Information System (INIS)

    Brown, R.M.

    1995-03-01

    Food items locally grown near Perth, Ontario and grocery store produce and locally grown items from the Pickering-Ajax area in the vicinity of the Pickering Nuclear Generating Station (PNGS) have been analyzed for free water tritium (HTO) and organically bound tritium (OBT). The technique of measuring 3 He ingrowth in samples by mass spectrometry has been used because of its sensitivity and freedom from opportunity for contamination during processing and measurement. Concentrations observed at each site were of the order expected on the basis of known levels of tritium in the local atmosphere and precipitation. There was considerable variation between different materials and limited correlation between materials of a single type. (author). 10 refs., 8 tabs., 4 figs

  10. Assessment of treatment options for rectosigmoid cancer: single-incision plus one port laparoscopic surgery, single-incision laparoscopic surgery, and conventional laparoscopic surgery.

    Science.gov (United States)

    Liu, Ruoyan; Wang, Yanan; Zhang, Ze; Li, Tingting; Liu, Hao; Zhao, Liying; Deng, Haijun; Li, Guoxin

    2017-06-01

    The advantages of reduced-port laparoscopic surgery (RPLS) for rectosigmoid cancer treatment have been disputed. This study evaluated the outcomes of RPLS compared to conventional laparoscopic surgery (CLS) for rectosigmoid cancer. Data from 211 patients who underwent a selective sigmoidectomy or anterior resection from August 2011 to June 2014 at a single institution were collected and analyzed via propensity score matching. Operative outcomes, inflammatory responses, pain intensity, oncologic outcomes, quality of life, and cosmetic results were compared between groups. After matching, 96 patients (48 CLS and 48 RPLS) were evaluated. Sixteen RPLS cases underwent single-incision laparoscopic surgery (SILS), and 32 underwent single-incision plus one port laparoscopic surgery (SILS + 1). Baseline clinical characteristics were comparable between the RPLS and the CLS groups. Morbidity, pathologic outcomes, and 3-year disease-free survival and overall survival rates were also comparable between the 2 groups. Compared with the CLS group, the RPLS group had a shorter total incision length (p time to liquid diet (p = 0.027), ambulation (p = 0.026), and discharge (p times, C-reactive protein levels at 24 h and 96 h, and interleukin-6 levels at 24 h postoperatively were significantly lower in the SILS + 1 group than those in the CLS and SILS groups (p cosmetic results, and both groups showed better results than the CLS group (p < 0.001). RPLS for rectosigmoid cancer is feasible, with short-term safety and long-term oncological safety comparable to that of CLS. Better cosmesis and accelerated recovery can be expected. SILS + 1 is a better choice than CLS or SILS for rectosigmoid cancer because it minimizes invasiveness and reduces technical difficulties.

  11. Assessing single-stranded oligonucleotide drug-induced effects in vitro reveals key risk factors for thrombocytopenia.

    Directory of Open Access Journals (Sweden)

    Sabine Sewing

    Full Text Available Single-stranded oligonucleotides (ON comprise a promising therapeutic platform that enables selective modulation of currently undruggable targets. The development of novel ON drug candidates has demonstrated excellent efficacy, but in certain cases also some safety liabilities were reported. Among them are events of thrombocytopenia, which have recently been evident in late stage trials with ON drugs. The underlying mechanisms are poorly understood and the risk for ON candidates causing such events cannot be sufficiently assessed pre-clinically. We investigated potential thrombocytopenia risk factors of ONs and implemented a set of in vitro assays to assess these risks. Our findings support previous observations that phosphorothioate (PS-ONs can bind to platelet proteins such as platelet collagen receptor glycoprotein VI (GPVI and activate human platelets in vitro to various extents. We also show that these PS-ONs can bind to platelet factor 4 (PF4. Binding to platelet proteins and subsequent activation correlates with ON length and connected to this, the number of PS in the backbone of the molecule. Moreover, we demonstrate that locked nucleic acid (LNA ribosyl modifications in the wings of the PS-ONs strongly suppress binding to GPVI and PF4, paralleled by markedly reduced platelet activation. In addition, we provide evidence that PS-ONs do not directly affect hematopoietic cell differentiation in culture but at higher concentrations show a pro-inflammatory potential, which might contribute to platelet activation. Overall, our data confirm that certain molecular attributes of ONs are associated with a higher risk for thrombocytopenia. We propose that applying the in vitro assays discussed here during the lead optimization phase may aid in deprioritizing ONs with a potential to induce thrombocytopenia.

  12. Psychometric evaluation of the 10-item Short Opiate Withdrawal Scale-Gossop (SOWS-Gossop) in patients undergoing opioid detoxification.

    Science.gov (United States)

    Vernon, Margaret K; Reinders, Stefan; Mannix, Sally; Gullo, Kristen; Gorodetzky, Charles W; Clinch, Thomas

    2016-09-01

    The Short Opiate Withdrawal Scale (SOWS)-Gossop is a 10-item questionnaire developed to evaluate opioid withdrawal symptom severity. The scale was derived from the original 32-item Opiate Withdrawal Scale in order to reduce redundancy while providing an equally sensitive measure of opioid withdrawal symptom severity appropriate for research and clinical practice. The objective of this study was to examine the psychometric properties and provide score interpretation guidelines for the SOWS-Gossop 10-item version. Blinded, pooled data from two trials assessing the efficacy of lofexidine hydrochloride in reducing withdrawal symptoms in patients undergoing opioid detoxification were used to evaluate the quantitative psychometric properties and score interpretation of the SOWS-Gossop. Five hundred fifty-five (N=555) observations were available at baseline with numbers decreasing to n=213 at day 7. Mean (standard deviation) SOWS-Gossop scores were 10.4 (6.86) at baseline, 8.7 (6.49) on day 1, 10.5 (7.21) on day 2, and 3.1 (3.95) on day 7. Confirmatory factor analysis indicated that the SOWS-Gossop items loaded on a single factor consistent with a single total score. Intra-class correlations (95% confidence interval) were 0.78 (0.70-0.85) between baseline and day 1, 0.84 (0.79-0.89) between days 4 and 5, and 0.88 (0.83-0.91) between days 6 and 7, demonstrating good test-retest reliability. Mean SOWS-Gossop scores varied significantly (popioid withdrawal and has excellent psychometric properties. The SOWS-Gossop is an appropriate, precise, and sensitive measure to evaluate the symptoms of acute opioid withdrawal in research or clinical settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Alterations of Regional Cerebral Blood Flow in Tinnitus Patients as Assessed Using Single-Photon Emission Computed Tomography.

    Directory of Open Access Journals (Sweden)

    Takashi Ueyama

    Full Text Available Tinnitus is the perception of phantom sound without an external auditory stimulus. Using neuroimaging techniques, such as positron emission tomography, electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI, many studies have demonstrated that abnormal functions of the central nervous system are closely associated with tinnitus. In our previous research, we reported using resting-state fMRI that several brain regions, including the rectus gyrus, cingulate gyrus, thalamus, hippocampus, caudate, inferior temporal gyrus, cerebellar hemisphere, and medial superior frontal gyrus, were associated with tinnitus distress and loudness. To reconfirm these results and probe target regions for repetitive transcranial magnetic stimulation (rTMS, we investigated the regional cerebral blood flow (rCBF between younger tinnitus patients (<60 years old and the age-matched controls using single-photon emission computed tomography and easy Z-score imaging system. Compared with that of controls, the rCBF of tinnitus patients was significantly lower in the bilateral medial superior frontal gyri, left middle occipital gyrus and significantly higher in the bilateral cerebellar hemispheres and vermis, bilateral middle temporal gyri, right fusiform gyrus. No clear differences were observed between tinnitus patients with normal and impaired hearing. Regardless of the assessment modality, similar brain regions were identified as characteristic in tinnitus patients. These regions are potentially involved in the pathophysiology of chronic subjective tinnitus.

  14. Safety and efficacy assessment of carotid artery stenting in a high-risk population in a single-centre registry.

    Science.gov (United States)

    Kosowski, Michał; Zimoch, Wojciech; Gwizdek, Tomasz; Konieczny, Radosław; Kübler, Piotr; Telichowski, Artur; Jankowska, Ewa A; Reczuch, Krzysztof

    2014-01-01

    Ischaemic stroke is the primary cause of long-term disability and the third most common cause of death. Internal carotid artery stenosis is an important risk factor for stroke and transient ischaemic attack (TIA). European Society of Cardiology (ESC) and American Heart Association (AHA) guidelines allow carotid artery stenting (CAS) as an alternative to endarterectomy in centres with low rates of death or stroke. To assess the safety and efficacy of CAS in a single-centre observation. We performed a retrospective analysis of all patients treated with CAS between March 2008 and July 2012. Clinical data and outcomes in both asymptomatic and symptomatic patients were analysed. A total of 214 consecutive patients were included in the registry. Symptomatic patients accounted for 57% of the study group and were more likely to have a history of stroke and/or TIA that occurred more than 6 months before the procedure (50% vs. 8%, p likely to have a history of coronary artery disease (88% vs. 61%, p < 0.001), and the rates of previous acute coronary syndrome and revascularisation were also higher in this group (58% vs. 41% and 71% vs. 52%, respectively, both p < 0.05). The symptomatic group had higher incidence of stroke in periprocedural and 30-day observation (4% vs. 0%, p < 0.05). There was no difference in incidence of adverse events in long-term observation. Carotid artery stenting is a safe and efficacious procedure. Every centre performing CAS should monitor the rate of periprocedural complications.

  15. Empirical Comparison of Simple Sequence Repeats and Single Nucleotide Polymorphisms in Assessment of Maize Diversity and Relatedness

    Science.gov (United States)

    Hamblin, Martha T.; Warburton, Marilyn L.; Buckler, Edward S.

    2007-01-01

    While Simple Sequence Repeats (SSRs) are extremely useful genetic markers, recent advances in technology have produced a shift toward use of single nucleotide polymorphisms (SNPs). The different mutational properties of these two classes of markers result in differences in heterozygosities and allele frequencies that may have implications for their use in assessing relatedness and evaluation of genetic diversity. We compared analyses based on 89 SSRs (primarily dinucleotide repeats) to analyses based on 847 SNPs in individuals from the same 259 inbred maize lines, which had been chosen to represent the diversity available among current and historic lines used in breeding. The SSRs performed better at clustering germplasm into populations than did a set of 847 SNPs or 554 SNP haplotypes, and SSRs provided more resolution in measuring genetic distance based on allele-sharing. Except for closely related pairs of individuals, measures of distance based on SSRs were only weakly correlated with measures of distance based on SNPs. Our results suggest that 1) large numbers of SNP loci will be required to replace highly polymorphic SSRs in studies of diversity and relatedness and 2) relatedness among highly-diverged maize lines is difficult to measure accurately regardless of the marker system. PMID:18159250

  16. Assessment of performance and utility of mortality prediction models in a single Indian mixed tertiary intensive care unit.

    Science.gov (United States)

    Sathe, Prachee M; Bapat, Sharda N

    2014-01-01

    To assess the performance and utility of two mortality prediction models viz. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) in a single Indian mixed tertiary intensive care unit (ICU). Secondary objectives were bench-marking and setting a base line for research. In this observational cohort, data needed for calculation of both scores were prospectively collected for all consecutive admissions to 28-bedded ICU in the year 2011. After excluding readmissions, discharges within 24 h and age predicted mortality had strong association with true mortality (R (2) = 0.98 for APACHE II and R (2) = 0.99 for SAPS II). Both models performed poorly in formal Hosmer-Lemeshow goodness-of-fit testing (Chi-square = 12.8 (P = 0.03) for APACHE II, Chi-square = 26.6 (P = 0.001) for SAPS II) but showed good discrimination (area under receiver operating characteristic curve 0.86 ± 0.013 SE (P care and comparing performances of different units without customization. Considering comparable performance and simplicity of use, efforts should be made to adapt SAPS II.

  17. Validation of 5-item and 2-item questionnaires in Chinese version of Dizziness Handicap Inventory for screening objective benign paroxysmal positional vertigo.

    Science.gov (United States)

    Chen, Wei; Shu, Liang; Wang, Qian; Pan, Hui; Wu, Jing; Fang, Jie; Sun, Xu-Hong; Zhai, Yu; Dong, You-Rong; Liu, Jian-Ren

    2016-08-01

    As possible candidate screening instruments for benign paroxysmal positional vertigo (BPPV), studies to validate the Dizziness Handicap Inventory (DHI) sub-scale (5-item and 2-item) and total scores are rare in China. From May 2014 to December 2014, 108(55 with and 53 without BPPV) patients complaining of episodic vertigo in the past week from a vertigo outpatient clinic were enrolled for DHI evaluation, as well as demographic and other clinical data. Objective BPPV was subsequently determined by positional evoking maneuvers under the record of optical Frenzel glasses. Cronbach's coefficient α was used to evaluate the reliability of psychometric scales. The validity of DHI total, 5-item and 2-item questionnaires to screen for BPPV was assessed by receiver operating characteristic (ROC) curves. It revealed that the DHI 5-item questionnaire had good internal consistency (Cronbach's coefficient α = 0.72). Area under the curve of total DHI, 5-item and 2-item scores for discriminating BPPV from those without was 0.678 (95 % CI 0.578-0.778), 0.873(95 % CI 0.807-0.940) and 0.895(95 % CI 0.836-0.953), respectively. It revealed 74.5 % sensitivity and 88.7 % specificity in separating BPPV and those without, with a cutoff value of 12 in the 5-item questionnaire. The corresponding rate of sensitivity and specificity was 78.2 and 88.7 %, respectively, with a cutoff value of 6 in 2-item questionnaire. The present study indicated that both 5-item and 2-item questionnaires in the Chinese version of DHI may be more valid than DHI total score for screening objective BPPV and merit further application in clinical practice in China.

  18. Poisson and negative binomial item count techniques for surveys with sensitive question.

    Science.gov (United States)

    Tian, Guo-Liang; Tang, Man-Lai; Wu, Qin; Liu, Yin

    2017-04-01

    Although the item count technique is useful in surveys with sensitive questions, privacy of those respondents who possess the sensitive characteristic of interest may not be well protected due to a defect in its original design. In this article, we propose two new survey designs (namely the Poisson item count technique and negative binomial item count technique) which replace several independent Bernoulli random variables required by the original item count technique with a single Poisson or negative binomial random variable, respectively. The proposed models not only provide closed form variance estimate and confidence interval within [0, 1] for the sensitive proportion, but also simplify the survey design of the original item count technique. Most importantly, the new designs do not leak respondents' privacy. Empirical results show that the proposed techniques perform satisfactorily in the sense that it yields accurate parameter estimate and confidence interval.

  19. Small-Item Vapor Test Method, FY11 Release

    Science.gov (United States)

    2012-07-01

    technology (S&T), T&E, and developmental and operational testing (DT/OT) activities , technology readiness assessments (TRA) to determine technology...powders, wipes), or gas-phase ( fumigants , including aerosols). decontamination process: The process of making any person, object, or area safe by...delivered to item. ■ Vaporous decontaminants: injection rate, flow rate, fumigant concentration, temperature, and relative humidity. ■ Liquid

  20. Test-retest reliability of selected items of Health Behaviour in School-aged Children (HBSC survey questionnaire in Beijing, China

    Directory of Open Access Journals (Sweden)

    Liu Yang

    2010-08-01

    Full Text Available Abstract Background Children's health and health behaviour are essential for their development and it is important to obtain abundant and accurate information to understand young people's health and health behaviour. The Health Behaviour in School-aged Children (HBSC study is among the first large-scale international surveys on adolescent health through self-report questionnaires. So far, more than 40 countries in Europe and North America have been involved in the HBSC study. The purpose of this study is to assess the test-retest reliability of selected items in the Chinese version of the HBSC survey questionnaire in a sample of adolescents in Beijing, China. Methods A sample of 95 male and female students aged 11 or 15 years old participated in a test and retest with a three weeks interval. Student Identity numbers of respondents were utilized to permit matching of test-retest questionnaires. 23 items concerning physical activity, sedentary behaviour, sleep and substance use were evaluated by using the percentage of response shifts and the single measure Intraclass Correlation Coefficients (ICC with 95% confidence interval (CI for all respondents and stratified by gender and age. Items on substance use were only evaluated for school children aged 15 years old. Results The percentage of no response shift between test and retest varied from 32% for the item on computer use at weekends to 92% for the three items on smoking. Of all the 23 items evaluated, 6 items (26% showed a moderate reliability, 12 items (52% displayed a substantial reliability and 4 items (17% indicated almost perfect reliability. No gender and age group difference of the test-retest reliability was found except for a few items on sedentary behaviour. Conclusions The overall findings of this study suggest that most selected indicators in the HBSC survey questionnaire have satisfactory test-retest reliability for the students in Beijing. Further test-retest studies in a large