WorldWideScience

Sample records for subscale items loaded

  1. The development of the items-easy (Ie) and items-difficult (Id) subscales for the MMPI-A.

    Science.gov (United States)

    Krakauer, S Y; Archer, R P; Gordon, R A

    1993-06-01

    This research involves the development, validation, and cross-validation of the Items-Easy (Ie) and Items-Difficult (Id) subscales for the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; Butcher et al., 1992). These subscales were designed to assess the degree to which reading comprehension deficits may be responsible for significant elevations of validity Scale F and the standard clinical scales on adolescents' MMPI-A profiles. A difference score, bared on the two 13-item subscales, was created in order to compare subjects' responses to subsets of the more comprehensible (Ie) and less comprehensible (Id) items within the test. Hit rate, sensitivity, specificity, positive predictive power, and negative predictive power were calculated on the basis of simple (Id - Ie) and weighted (3Id - 1Ie) difference scores for the validation (N = 495) and cross-validation (N = 264) samples, and for specific high-F profile subsamples. Although some of the indices reflected classification accuracy as high as 95%, none of the indices yielded consistently high results across the various samples and subsamples. It has been concluded that the Ie and Id subscales should be used only for research purposes at this time.

  2. Item-level and subscale-level factoring of Biggs' Learning Process Questionnaire (LPQ) in a mainland Chinese sample.

    Science.gov (United States)

    Sachs, J; Gao, L

    2000-09-01

    The learning process questionnaire (LPQ) has been the source of intensive cross-cultural study. However, an item-level factor analysis of all the LPQ items simultaneously has never been reported. Rather, items within each subscale have been factor analysed to establish subscale unidimensionality and justify the use of composite subscale scores. It was of major interest to see if the six logically constructed items groups of the LPQ would be supported by empirical evidence. Additionally, it was of interest to compare the consistency of the reliability and correlational structure of the LPQ subscales in our study with those of previous cross-cultural studies. Confirmatory factor analysis was used to fit the six-factor item level model and to fit five representative subscale level factor models. A total of 1070 students between the ages of 15 to 18 years was drawn from a representative selection of 29 classes from within 15 secondary schools in Guangzhou, China. Males and females were almost equally represented. The six-factor item level model of the LPQ seemed to fit reasonably well, thus supporting the six dimensional structure of the LPQ and justifying the use of composite subscale scores for each LPQ dimension. However, the reliability of many of these subscales was low. Furthermore, only two subscale-level factor models showed marginally acceptable fit. Substantive considerations supported an oblique three-factor model. Because the LPQ subscales often show low internal consistency reliability, experimental and correlational studies that have used these subscales as dependent measures have been disappointing. It is suggested that some LPQ items should be revised and other items added to improve the inventory's overall psychometric properties.

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Lisa M Lix

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

  5. An Item Response Analysis of the Motor and Behavioral Subscales of the Unified Huntington's Disease Rating Scale in Huntington Disease Gene Expansion Carriers

    Science.gov (United States)

    Vaccarino, Anthony L.; Anderson, Karen; Borowsky, Beth; Duff, Kevin; Giuliano, Joseph; Guttman, Mark; Ho, Aileen K.; Orth, Michael; Paulsen, Jane S.; Sills, Terrence; van Kammen, Daniel P.; Evans, Kenneth R.

    2011-01-01

    Although the Unified Huntington's Disease Rating Scale (UHDRS) is widely used in the assessment of Huntington disease (HD), the ability of individual items to discriminate individual differences in motor or behavioral manifestations has not been extensively studied in HD gene expansion carriers without a motor-defined clinical diagnosis (i.e., prodromal-HD or prHD). To elucidate the relationship between scores on individual motor and behavioral UHDRS items and total score for each subscale, a non-parametric item response analysis was performed on retrospective data from two multicentre, longitudinal studies. Motor and Behavioral assessments were supplied for 737 prHD individuals with data from 2114 visits (PREDICT-HD) and 686 HD individuals with data from 1482 visits (REGISTRY). Option characteristic curves were generated for UHDRS subscale items in relation to their subscale score. In prHD, overall severity of motor signs was low and participants had scores of 2 or above on very few items. In HD, motor items that assessed ocular pursuit, saccade initiation, finger tapping, tandem walking, and to a lesser extent saccade velocity, dysarthia, tongue protrusion, pronation/supination, Luria, bradykinesia, choreas, gait and balance on the retropulsion test were found to discriminate individual differences across a broad range of motor severity. In prHD, depressed mood, anxiety, and irritable behavior demonstrated good discriminative properties. In HD, depressed mood demonstrated a good relationship with the overall behavioral score. These data suggest that at least some UHDRS items appear to have utility across a broad range of severity, although many items demonstrate problematic features. PMID:21370269

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

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    Susan C. Gillmor

    2015-01-01

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

  7. The patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF)

    DEFF Research Database (Denmark)

    Crossley, Kay M; Macri, Erin M; Cowan, Sallie M

    2017-01-01

    for patellofemoral pain have methodological limitations. This study aimed to develop a new subscale of the Knee injury and Osteoarthritis Outcome Score for patellofemoral pain and osteoarthritis (KOOS-PF), and evaluate its measurement properties. METHODS: Items were generated using input from 50 patients...... and interpretability of the final version of KOOS-PF and other KOOS subscales. RESULTS: From an initial 80 generated items, the final subscale included 11 items. KOOS-PF items loaded predominantly on one factor, pain during activities that load the patellofemoral joint. KOOS-PF had good internal consistency (Cronbach......'s α 0.86) and adequate test-retest reliability (intraclass correlation coefficient 0.86). Hypothesis testing supported convergent, divergent and known-groups validity. Responsiveness was confirmed, with KOOS-PF demonstrating a moderate correlation with Global Rating of Change scores (r 0.52) and large...

  8. Longitudinal Construct Validity of Brief Symptom Inventory Subscales in Schizophrenia

    Science.gov (United States)

    Long, Jeffrey D.; Harring, Jeffrey R.; Brekke, John S.; Test, Mary Ann; Greenberg, Jan

    2007-01-01

    Longitudinal validity of Brief Symptom Inventory subscales was examined in a sample (N = 318) with schizophrenia-related illness measured at baseline and every 6 months for 3 years. Nonlinear factor analysis of items was used to test graded response models (GRMs) for subscales in isolation. The models varied in their within-time and between-times…

  9. Exploring measurement invariance by gender in the profile of mood states depression subscale among cancer survivors.

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    Kim, Jihye; Smith, Tenbroeck

    2017-01-01

    The Profile of Mood States-Short Form (POMS-SF) is a well-validated tool commonly used in medical/clinical research. Less attention has been paid to the measurement invariance of the POMS-the degree to which the structure and items behave similarly for different groups (e.g., women and men). This study investigated the measurement invariance of the POMS Depression subscale across gender groups in a sample of cancer survivors. The POMS Depression subscale has 8 items (Unhappy, Sad, Blue, Hopeless, Discouraged, Miserable, Helpless, and Worthless). Invariance was measured using multigroup confirmatory factor analysis. This study used data from American Cancer Society Studies of Cancer Survivors-II, a population-based survey of adult cancer survivors (n = 9170). We found factor structures and factor loadings were invariant for gender groups, but moderate differential item functioning (DIF) in the question containing the word blue. With regard to cancer survivors' gender, we found the Depression subscale of the POMS-SF had configural invariance, and partial metric and scalar invariance. This suggests that results should be interpreted with caution, especially when gender is considered important. More broadly, our finding suggests that questions with the word blue may introduce DIF into other measures of depressive mood. More research is needed to replicate these findings in other samples and with other instruments.

  10. A medical risk attitude subscale for DOSPERT

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    Shoshana Butler

    2012-03-01

    Full Text Available Background: The Domain-Specific Risk Taking scale (DOSPERT is a widely used instrument that measures perceived risk and benefit and attitude toward risk for activities in several domains, but does not include medical risks. Objective: To develop a medical risk domain subscale for DOSPERT. Methods: Sixteen candidate risk items were developed through expert discussion. We conducted cognitive telephone interviews, an online survey, and a random-digit dialing (RDD telephone survey to reduce and refine the scale, explore its factor structure, and obtain estimates of reliability. Participants: Eight patients recruited from UIC medical center waiting rooms participated in 45-60 minute cognitive interviews. Thirty Amazon Mechanical Turk workers completed the online survey. One hundred Chicago-area residents completed the RDD telephone survey. Results: On the basis of cognitive interviews, we eliminated five items due to poor variance or participant misunderstanding. The online survey suggested that two additional items were negatively correlated with the scale, and we considered them candidates for removal. Factor analysis of the responses in the RDD telephone survey and non-statistical factors led us to recommend a final set of 6 items to represent the medical risk domain. The final set of items included blood donation, kidney donation, daily medication use for allergies, knee replacement surgery, general anesthesia in dentistry, and clinical trial participation. The interitem reliability (Cronbach's alpha of the final set of 6 items ranged from 0.57-0.59 depending on the response task. Older respondents gave lower overall ratings of expected benefit from the activities. Conclusion: We refined a set of items to measure risk and benefit perceptions for medical activities. Our next step will be to add these items to the complete DOSPERT scale, confirm the scale's psychometric properties, determine whether medical risks constitute a psychologically

  11. Measuring Cognitive Load in Test Items: Static Graphics versus Animated Graphics

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    Dindar, M.; Kabakçi Yurdakul, I.; Inan Dönmez, F.

    2015-01-01

    The majority of multimedia learning studies focus on the use of graphics in learning process but very few of them examine the role of graphics in testing students' knowledge. This study investigates the use of static graphics versus animated graphics in a computer-based English achievement test from a cognitive load theory perspective. Three…

  12. Functional autonomy measurement system: development of a social subscale.

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    Pinsonnault, E; Desrosiers, J; Dubuc, N; Kalfat, H; Colvez, A; Delli-Colli, N

    2003-01-01

    The purpose of this study was to develop a subscale assessing social functioning for the functional autonomy measurement system (SMAF). The development of this new dimension was based on consultations (focus groups and nominal groups) of experts from different health care disciplines in Quebec, Canada, and France. Two interrater reliability studies were carried out with older people presenting a loss of functional autonomy and living either in an institution or at home. With the focus groups, the experts clarified the definition of social functioning and identified the factors involved. The nominal groups were used to construct a subscale composed of six items. The results of the first interrater reliability study showed a mean agreement percentage of 60% for the subscale and an intraclass correlation coefficient (ICC) of 0.70 (CI: 0.57-0.80). The results of the second interrater reliability study showed higher coefficients with an agreement percentage of 74% for the subscale and an ICC of 0.83 (CI: 0.61-0.93). These preliminary results demonstrate that the new social functioning subscale has good reliability, but more studies are needed to show its validity. The new SMAF, including the social functioning subscale, should help clinicians and researchers to obtain a comprehensive profile of functional autonomy. It could also contribute to the improvement of health care for older people.

  13. Education does not equally influence all the Mini Mental State Examination subscales and items: inferences from a Brazilian community sample A educação não influencia igualmente todas subescalas e itens do Mini-Exame do Estado Mental: inferências de uma amostra comunitária brasileira

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    Jerson Laks

    2010-09-01

    Full Text Available OBJECTIVE: Mini-Mental State Examination cutoffs have been presented for schooling levels to screen cognitive impairment. However, items may behave differently with regards to education. The objective of this study was to examine the impact of education on MMSE subscales and items. METHOD: Community-dwelling participants aged 65 years or more (n = 990, females = 637, age = 74.1 years, range 65-108 were stratified as illiterate (n = 373, 1-8 (n = 540, 9-12 (n = 63, and more than 12 years of schooling (n = 14 and were screened with MMSE and Pfeffer Functional Activities Questionnaire. To make the Mini-Mental State Examination items comparable, each item was transformed into z scores. Multiple linear regression was used to estimate the effect of schooling on MMSE subs and items controlling for age, sex, and activities of daily life. RESULTS: Temporal and space orientation, attention/calculation, repetition, reading, writing, and drawing scores improved as education increased, but not memory registration, three step command, and naming. Reading and writing displayed the largest coefficients, whereas education exerted no influence on naming and three step command tasks. CONCLUSION: Education does not exert an important effect on naming, three step command, memory registration, and delayed recall. As memory is a key factor for diagnosing dementia, these items could be considered despite education.OBJETIVO: Vários pontos de corte foram propostos para o Mini Exame do Estado Mental para rastrear cognição. Entretanto, os itens podem se comportar diferentemente dependendo da educação. O objetivo deste estudo foi examinar o impacto da educação nas subescalas e itens do Mini Exame do Estado Mental. MÉTODO: Participantes com idade de 65 anos ou mais e residentes na comunidade (n = 990, feminino = 637, idade = 74,1 anos, 65-108 foram estratificados como analfabetos (n = 373, 1-8 (n = 540, 9-12 (n = 63, e mais de 12 anos de escolaridade (n = 14 e foram

  14. Integrated Inventory Routing Problem with Quality Time Windows and Loading Cost for Deteriorating Items under Discrete Time

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    Tao Jia

    2014-01-01

    Full Text Available We investigate an integrated inventory routing problem (IRP in which one supplier with limited production capacity distributes a single item to a set of retailers using homogeneous vehicles. In the objective function we consider a loading cost which is often neglected in previous research. Considering the deterioration in the products, we set a soft time window during the transportation stage and a hard time window during the sales stage, and to prevent jams and waiting cost, the time interval of two successive vehicles returning to the supplier’s facilities is required not to be overly short. Combining all of these factors, a two-echelon supply chain mixed integer programming model under discrete time is proposed, and a two-phase algorithm is developed. The first phase uses tabu search to obtain the retailers’ ordering matrix. The second phase is to generate production scheduling and distribution routing, adopting a saving algorithm and a neighbourhood search, respectively. Computational experiments are conducted to illustrate the effectiveness of the proposed model and algorithm.

  15. A3 Subscale Diffuser Test Article Design

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    Saunders, G. P.

    2009-01-01

    This paper gives a detailed description of the design of the A3 Subscale Diffuser Test (SDT) Article Design. The subscale diffuser is a geometrically accurate scale model of the A3 altitude rocket facility. It was designed and built to support the SDT risk mitigation project located at the E3 facility at Stennis Space Center, MS (SSC) supporting the design and construction of the A3 facility at SSC. The subscale test article is outfitted with a large array of instrumentation to support the design verification of the A3 facility. The mechanical design of the subscale diffuser and test instrumentation are described here

  16. Evaluation of the Construction of the Subscales for the Piers-Harris and Tennessee Inventories.

    Science.gov (United States)

    Thomas, Julia Anne

    A sample of 234 fifth- and 259 sixth-grade students scaled the items of the Piers-Harris, Tennessee, Coopersmith, and Lipsett self-concept measures. The scaling of the Piers-Harris and the Tennessee inventories was examined in reference to their subscales. The present technique placed items on a bivariate plane of two orthogonal dimensions…

  17. Subscale Test Program for the Orion Conical Ribbon Drogue Parachute

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    Sengupta, Anita; Stuart, Phil; Machin, Ricardo; Bourland, Gary; Schwing, Allen; Longmire, Ellen; Henning, Elsa; Sinclair, Rob

    2011-01-01

    A subscale wind tunnel test program for Orion's conical ribbon drogue parachute is under development. The desired goals of the program are to quantify aerodynamic performance of the parachute in the wake of the entry vehicle, including understanding of the coupling of the parachute and command module dynamics, and an improved understanding of the load distribution within the textile elements of the parachute. The test program is ten percent of full scale conducted in a 3x2.1 m (10x7 ft) closed loop subsonic wind tunnel. The subscale test program is uniquely suited to probing the aerodynamic and structural environment in both a quantitative and qualitative manner. Non-intrusive diagnostics, including Particle Image Velocimetry for wake velocity surveys, high speed pressure transducers for canopy pressure distribution, and a high speed photogrammetric reconstruction, will be used to quantify the parachute's performance.

  18. Subscale Acoustic Testing: Comparison of ALAT and ASMAT

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    Houston, Janice D.; Counter, Douglas

    2014-01-01

    The liftoff phase induces acoustic loading over a broad frequency range for a launch vehicle. These external acoustic environments are then used in the prediction of internal vibration responses of the vehicle and components which result in the qualification levels. Thus, predicting these liftoff acoustic environments is critical to the design requirements of any launch vehicle. If there is a significant amount of uncertainty in the predictions or if acoustic mitigation options must be implemented, a subscale acoustic test is a feasible pre-launch test option. This paper compares the acoustic measurements of two different subscale tests: the 2% Ares Liftoff Acoustic Test conducted at Stennis Space Center and the 5% Ares I Scale Model Acoustic Test conducted at Marshall Space Flight Center.

  19. Development and psychometric evaluation of a 10-item short form inventory of gambling situations.

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    Smith, Caitlin; Stewart, Sherry H; O'Connor, Roisin M; Collins, Pamela; Katz, Joel

    2011-03-01

    The Inventory of Gambling Situations (IGS-63; Turner and Littman-Sharp, Inventory of gambling situations users guide, 2006) is a 63-item measure of high-risk gambling situations. It assesses gambling across 10 situational subscales that load onto two higher-order factors: negative and positive situations (Stewart et al. Psychology of Addictive Behaviors, 22:257-268, 2008). While the IGS-63 has excellent psychometric properties (Littman-Sharp et al., The Inventory of Gambling Situations: Reliability, factor structure, and validity (IGS Technical Manual), in press) its length may preclude its use in time-limited contexts. The purpose of this study was to develop and validate a 10-item short-form of the IGS (IGS-10). Each IGS-10 item reflects one of the ten subscale categories from the IGS-63, with two items from the original subscales included as examples for each IGS-10 item. The IGS-10 was administered to 180 undergraduate gamblers along with the IGS-63 and the Problem Gambling Severity Index (PGSI; Ferris and Wynne, Canadian Problem Gambling Index: Final report, 2001). IGS-10 items showed convergent validity with the corresponding IGS-63 subscales (r's = .60-.73). Principal components analysis of the IGS-10 revealed two factors: negative (α = .84) and positive (α = .85). PGSI scores correlated significantly with all IGS-10 items (r's = .33-.58) and with both IGS-10 higher-order subscales (r's = .66 [negative] and .49 [positive]), supporting the criterion validity of the IGS-10. Since minimal information is lost when using the IGS-10, the short form may prove particularly useful when respondent burden prevents using the full IGS-63.

  20. The Subjective Index for Physical and Social Outcome (SIPSO in Stroke: investigation of its subscale structure

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    George Steve

    2010-04-01

    Full Text Available Abstract Background Short and valid measures of the impact of a stroke on integration are required in health and social settings. The Subjective Index of Physical and Social Outcome (SIPSO is one such measure. However, there are questions whether scores can be summed into a total score or whether subscale scores should be calculated. This paper aims to provide clarity on the internal construct validity of the subscales and the total scale. Methods SIPSO data were collected as part of two parallel surveys of the met and unmet needs of 445 younger people (aged 18-65 with non-recent stroke (at least one year and living at home. Factor, Mokken and Rasch analysis were used. Results Factor analysis supported a two factor structure (explaining 68% of the variance as did the Mokken analysis (overall Loevinger coefficient 0.77 for the Physical Integration subscale; 0.51 for the Social Integration subscale. Both subscales fitted the Rasch model (P > 0.01 after adjusting for some observed differential item functioning. The 10-items together did not fit the Rasch model. Conclusions The SIPSO subscales are valid for use with stroke patients of working age but the total SIPSO is not. The conversion table can be used by clinicians and researchers to convert ordinal data to interval level prior to mathematical operations and other parametric procedures. Further work is required to explore the occurrence of bias by gender for some of the items.

  1. Relating Unidimensional IRT Parameters to a Multidimensional Response Space: A Review of Two Alternative Projection IRT Models for Scoring Subscales

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    Kahraman, Nilufer; Thompson, Tony

    2011-01-01

    A practical concern for many existing tests is that subscore test lengths are too short to provide reliable and meaningful measurement. A possible method of improving the subscale reliability and validity would be to make use of collateral information provided by items from other subscales of the same test. To this end, the purpose of this article…

  2. Oxidation subscale of gamma-titanium aluminide

    NARCIS (Netherlands)

    Beye, R.; Verwerft, Marc; de Hosson, J.T.M.; Gronsky, R.

    1996-01-01

    The subscale formed during high temperature rapid oxidation of gamma-titanium aluminum is revealed by transmission electron microscopy and microanalysis to consist of two phases: one hexagonal with unit cell dimensions a = 0.58 nm, c = 0.47 nm (+/- 0.005 nm), and a composition close to Ti6Al3O4; the

  3. Ethical Perspectives: Leadership Subscales Applied to Education.

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    Gable, Sherry K.; Kavich, Larry L.

    Ethical perspectives are needed to gain insight into the history of leader behavior, especially as related to the current emphasis on contingency and Path-Goal Theories. An instrument to help select professionals who reflect ethical traits is the Leadership Behavior Description Questionnaire with 12 leadership subscales (LBDQ, Form XII). Selected…

  4. Wind Turbine Blade Design for Subscale Testing

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    Hassanzadeh, Arash; Naughton, Jonathan W.; Kelley, Christopher L.; Maniaci, David C.

    2016-09-01

    Two different inverse design approaches are proposed for developing wind turbine blades for sub-scale wake testing. In the first approach, dimensionless circulation is matched for full scale and sub-scale wind turbine blades for equal shed vorticity in the wake. In the second approach, the normalized normal and tangential force distributions are matched for large scale and small scale wind turbine blades, as these forces determine the wake dynamics and stability. The two approaches are applied for the same target full scale turbine blade, and the shape of the blades are compared. The results show that the two approaches have been successfully implemented, and the designed blades are able to produce the target circulation and target normal and tangential force distributions.

  5. Analysis of the Subscales of the Tennessee Self-Concept Scale.

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    Gellen, Murray I.; Hoffman, Roy A.

    1984-01-01

    Factor analyzed the item responses comprising each of the five external dimensions and the three internal dimensions of the Tennessee Self-Concept Scale. The results indicated that seven of the eight subscales are essentially single-factor scales. Implications for counseling are discussed. (Author)

  6. Subscales of the vestibular activities and participation questionnaire could be applied across cultures.

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    Mueller, Martin; Whitney, Susan L; Alghwiri, Alia; Alshebber, Kefah; Strobl, Ralf; Alghadir, Ahmad; Al-momani, Murad O; Furman, Joseph M; Grill, Eva

    2015-02-01

    The objective of this study was to assess the objectivity, cross-cultural validity, and convergent validity of the Vestibular Activities and Participation (VAP) questionnaire among four countries, Germany, United States, Jordan, and Saudi Arabia. This was a cross-sectional study conducted in four specialized outpatient dizziness clinics in Germany, United States, Jordan, and Saudi Arabia. A total of 453 participants were included in the study. The Rasch analysis revealed two separate subscales. Subscale 1 items included focusing attention, lying down, standing, bending, lifting and carrying objects, and sports. Subscale 2 items included walking long distances, climbing, running, moving around within buildings other than home, using transportation, and driving. The Pearson product-moment correlation between the Dizziness Handicap Inventory and the summary score of the VAP subscale 1 was 0.66 and was 0.64 for subscale 2. Owing to its shortness and intercultural adaptability, the new two-scale version of the VAP questionnaire lends itself to clinical practice and research across countries to estimate the effect of vertigo and dizziness on activity limitation and participation restrictions. Psychometrically sound summary scores can be calculated. More extended versions of the VAP can be used for comprehensive clinical assessment where summary scores are not needed or a more detailed documentation is warranted. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. [Measuring workplace climate: reliability and validity of the 12-item Organizational Climate Scale (OCS-12)].

    Science.gov (United States)

    Fukui, Satoe; Haratani, Takashi; Toshima, Yutaka; Shima, Satoru; Takahashi, Masaya; Nakata, Akinori; Fukasawa, Kenji; Ohba, Sayo; Sato, Emi; Hirota, Yasuko

    2004-11-01

    In order to investigate the reliability and validity of the short version of the 30-item Organizational Climate Scale (OCS-30; Toshima and Matsuda, 1992, 1995), a self-administered questionnaire was conducted in a sample of 819 employees of two medium-sized private companies in Japan by using the OCS-30, the Generic Job Stress Questionnaire (GJSQ), and the 12-item General Health Questionnaire (GHQ-12). The OCS has two subscales, i.e., the Tradition Scale (TS) and the Organizational Environment Scale (OES). The organizational climate perceived by each worker can be grouped into four categories based on the subscale scores: low TS and high OES (Active), high TS and high OES (Governed), low TS and low OES (Disorganized), and high TS and low OES (Reluctant). Principal component analysis for the OCS-30 was submitted (varimax rotation, the number of factors = 2), and 6 items for each factor, with factor loadings greater than 0.50, were selected for the short version, which constituted the 12-item Organizational Climate Scale (OCS-12). Cronbach's alpha reliability coefficients of the two subscales of the OCS-12 were acceptable; 0.63 for the TS and 0.71 for the OES. Both two subscales of the OCS-12 were significantly correlated with the GHQ-12 and many subscales of the GJSQ, which indicated the good constructive validity of the OCS-12. Among 4 types of organizational climate categorized by the OCS-12, the "Active" group showed the lowest job stress scores. It is suggested that the OCS-12 could be a reliable and valid instrument for assessing workers' perception of workplace climate.

  8. Item Banking.

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    Rudner, Lawrence

    1999-01-01

    Discusses the advantages and disadvantages of using item banks while providing useful information to those who are considering implementing an item banking project in their school district. The primary advantage of item banking is in test development. Also describes start-up activities in implementing item banking. (SLD)

  9. Development and validation of the functional assessment of cancer therapy-antiangiogenesis subscale.

    Science.gov (United States)

    Kaiser, Karen; Beaumont, Jennifer L; Webster, Kimberly; Yount, Susan E; Wagner, Lynne I; Kuzel, Timothy M; Cella, David

    2015-05-01

    The Functional Assessment of Cancer Therapy (FACT)-Antiangiogenesis (AntiA) Subscale was developed and validated to enhance treatment decision-making and side effect management for patients receiving anti-angiogenesis therapies. Side effects related to anti-angiogenesis therapies were identified from the literature, clinician input, and patient input. Fifty-nine possible patient expressions of side effects were generated. Patient and clinician ratings of the importance of these expressions led us to develop a 24-item questionnaire with clinical and research potential. To assess the scale's reliability and validity, 167 patients completed the AntiA Subscale, the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-Kidney Symptom Index (FKSI), the FACIT-Fatigue Subscale, the Global Rating of Change Scale (GRC), and the PROMIS Global Health Scale. Patient responses to the AntiA were analyzed for internal consistency, test-retest reliability, convergent and discriminant validity, and responsiveness to change in clinical status. All tested scales were found to have good internal consistency reliability (Cronbach's alpha 0.70-0.92). Test-retest reliability was also good (0.72-0.88) for total and subscale scores and lower for individual items. The total score, subscale scores, and all single items (except nosebleeds) significantly differentiated between groups defined by level of side effect bother. Evaluation of responsiveness to change in this study was not conclusive, suggesting an area for further research. The AntiA is a reliable and valid measure of side effects from anti-angiogenesis therapy. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  10. Development and validation of the functional assessment of cancer therapy–antiangiogenesis subscale

    Science.gov (United States)

    Kaiser, Karen; Beaumont, Jennifer L; Webster, Kimberly; Yount, Susan E; Wagner, Lynne I; Kuzel, Timothy M; Cella, David

    2015-01-01

    The Functional Assessment of Cancer Therapy (FACT)–Antiangiogenesis (AntiA) Subscale was developed and validated to enhance treatment decision-making and side effect management for patients receiving anti-angiogenesis therapies. Side effects related to anti-angiogenesis therapies were identified from the literature, clinician input, and patient input. Fifty-nine possible patient expressions of side effects were generated. Patient and clinician ratings of the importance of these expressions led us to develop a 24-item questionnaire with clinical and research potential. To assess the scale's reliability and validity, 167 patients completed the AntiA Subscale, the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-Kidney Symptom Index (FKSI), the FACIT-Fatigue Subscale, the Global Rating of Change Scale (GRC), and the PROMIS Global Health Scale. Patient responses to the AntiA were analyzed for internal consistency, test–retest reliability, convergent and discriminant validity, and responsiveness to change in clinical status. All tested scales were found to have good internal consistency reliability (Cronbach's alpha 0.70–0.92). Test–retest reliability was also good (0.72–0.88) for total and subscale scores and lower for individual items. The total score, subscale scores, and all single items (except nosebleeds) significantly differentiated between groups defined by level of side effect bother. Evaluation of responsiveness to change in this study was not conclusive, suggesting an area for further research. The AntiA is a reliable and valid measure of side effects from anti-angiogenesis therapy. PMID:25619758

  11. Results of subscale MTF compression experiments

    Science.gov (United States)

    Howard, Stephen; Mossman, A.; Donaldson, M.; Fusion Team, General

    2016-10-01

    In magnetized target fusion (MTF) a magnetized plasma torus is compressed in a time shorter than its own energy confinement time, thereby heating to fusion conditions. Understanding plasma behavior and scaling laws is needed to advance toward a reactor-scale demonstration. General Fusion is conducting a sequence of subscale experiments of compact toroid (CT) plasmas being compressed by chemically driven implosion of an aluminum liner, providing data on several key questions. CT plasmas are formed by a coaxial Marshall gun, with magnetic fields supported by internal plasma currents and eddy currents in the wall. Configurations that have been compressed so far include decaying and sustained spheromaks and an ST that is formed into a pre-existing toroidal field. Diagnostics measure B, ne, visible and x-ray emission, Ti and Te. Before compression the CT has an energy of 10kJ magnetic, 1 kJ thermal, with Te of 100 - 200 eV, ne 5x1020 m-3. Plasma was stable during a compression factor R0/R >3 on best shots. A reactor scale demonstration would require 10x higher initial B and ne but similar Te. Liner improvements have minimized ripple, tearing and ejection of micro-debris. Plasma facing surfaces have included plasma-sprayed tungsten, bare Cu and Al, and gettering with Ti and Li.

  12. Latent variable mixture models to test for differential item functioning: a population-based analysis.

    Science.gov (United States)

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

    2017-05-15

    Comparisons of population health status using self-report measures such as the SF-36 rest on the assumption that the measured items have a common interpretation across sub-groups. However, self-report measures may be sensitive to differential item functioning (DIF), which occurs when sub-groups with the same underlying health status have a different probability of item response. This study tested for DIF on the SF-36 physical functioning (PF) and mental health (MH) sub-scales in population-based data using latent variable mixture models (LVMMs). Data were from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective national cohort study. LVMMs were applied to the ten PF and five MH SF-36 items. A standard two-parameter graded response model with one latent class was compared to multi-class LVMMs. Multivariable logistic regression models with pseudo-class random draws characterized the latent classes on demographic and health variables. The CaMos cohort consisted of 9423 respondents. A three-class LVMM fit the PF sub-scale, with class proportions of 0.59, 0.24, and 0.17. For the MH sub-scale, a two-class model fit the data, with class proportions of 0.69 and 0.31. For PF items, the probabilities of reporting greater limitations were consistently higher in classes 2 and 3 than class 1. For MH items, respondents in class 2 reported more health problems than in class 1. Differences in item thresholds and factor loadings between one-class and multi-class models were observed for both sub-scales. Demographic and health variables were associated with class membership. This study revealed DIF in population-based SF-36 data; the results suggest that PF and MH sub-scale scores may not be comparable across sub-groups defined by demographic and health status variables, although effects were frequently small to moderate in size. Evaluation of DIF should be a routine step when analysing population-based self-report data to ensure valid comparisons amongst sub-groups.

  13. Simulation of a GOX-kerosene subscale rocket combustion chamber

    Science.gov (United States)

    Höglauer, Christoph; Kniesner, Björn; Knab, Oliver; Kirchberger, Christoph; Schlieben, Gregor; Kau, Hans-Peter

    2011-12-01

    In view of future film cooling tests at the Institute for Flight Propulsion (LFA) at Technische Universität München, the Astrium in-house spray combustion CFD tool Rocflam-II was validated against first test data gained from this rocket test bench without film cooling. The subscale rocket combustion chamber uses GOX and kerosene as propellants which are injected through a single double swirl element. Especially the modeling of the double swirl element and the measured wall roughness were adapted on the LFA hardware. Additionally, new liquid kerosene fluid properties were implemented and verified in Rocflam-II. Also the influences of soot deposition and hot gas radiation on the wall heat flux were analytically and numerically estimated. In context of reviewing the implemented evaporation model in Rocflam-II, the binary diffusion coefficient and its pressure dependency were analyzed. Finally simulations have been performed for different load points with Rocflam-II showing a good agreement compared to test data.

  14. The Mechanical Performance of Subscale Candidate Elastomer Docking Seals

    Science.gov (United States)

    Bastrzyk, Marta B.; Daniels, Christopher C.

    2010-01-01

    The National Aeronautics and Space Administration is developing a Low Impact Docking System (LIDS) for future exploration missions. The mechanism is a new state-of-the-art device for in-space assembly of structures and rendezvous of vehicles. At the interface between two pressurized modules, each with a version of the LIDS attached, a composite elastomer-metal seal assembly prevents the breathable air from escaping into the vacuum of space. Attached to the active LIDS, this seal mates against the passive LIDS during docking operation. The main interface seal assembly must exhibit low leak and outgas values, must be able to withstand various harsh space environments, must remain operational over a range of temperatures from -50 C to 75 C, and perform after numerous docking cycles. This paper presents results from a comprehensive study of the mechanical performance of four candidate subscale seal assembly designs at -50, 23, 50, and 75 C test temperatures. In particular, the force required to fully compress the seal during docking, and that which is required for separation during the undocking operation were measured. The height of subscale main interface seal bulbs, as well as the test temperature, were shown to have a significant effect on the forces the main interface seal of the LIDS may experience during docking and undocking operations. The average force values required to fully compress each of the seal assemblies were shown to increase with test temperature by approximately 50% from -50 to 75 C. Also, the required compression forces were shown to increase as the height of the seal bulb was increased. The seal design with the tallest elastomer seal bulb, which was 31% taller than that with the shortest bulb, required force values approximately 45% higher than those for the shortest bulb, independent of the test temperature. The force required to separate the seal was shown to increase with decreasing temperature after 15 hours of simulated docking. No adhesion

  15. [Turkish expressive and receptive language test: I. Standardization, reliability and validity study of the receptive vocabulary sub-scale].

    Science.gov (United States)

    Kazak Berument, Sibel; Güven, Ayşe Gül

    2013-01-01

    A reliable, valid and original test to assess the receptive vocabulary skills of children in Turkey was not available. Thus, the purpose of the current study was to develop a receptive vocabulary test for Turkish children based on the Turkish language. For the Receptive Vocabulary Sub-Scale (TIFALDI-RT) 242 concrete and abstract words were chosen from word frequency lists and a comprehensive Turkish Dictionary. Pilot data were collected from 648 children aged 2 to 13 from Ankara, and norm data were collected from a nationally representative sample of 3755 children. Item analysis (item difficulty, discrimination and distractor) was carried out on the pilot data and based on the results, the total item number was reduced to 157. Further, three parameter item analyses (IRT) were carried out on the norm data by using BILOG-MG (SSI, 2002), and the results indicated that the TIFALDI Receptive Vocabulary Sub-Scale could be reduced to 104 items to assess 2 to 12 year-old children's receptive vocabulary. Test-retest and internal consistency reliabilities were calculated for the whole sample and age groups separately, and all the coefficients were high. For the validity, the relationship between the WISC-R and Ankara Developmental Screening Inventory (AGTE) and Receptive Vocabulary Sub-Scale were investigated. Once again, the TIFALDI Receptive Vocabulary Sub-Scale scores were found to be significantly related to WISC-R and AGTE scores. The TIFALDI Receptive Vocabulary Sub-Scale was developed on the basis of the Turkish Language and norm data were collected from a nationally representative sample. The TIFALDI-RT also had a high reliability and validity. Thus, the TIFALDI-RT can be used to assess 2 to 12 year-old children's receptive vocabulary skills.

  16. 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.

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

    Science.gov (United States)

    Noor, Syed W.; Galos, Dylan L.; Simon Rosser, B. R.

    2017-01-01

    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 R2 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. PMID:26292840

  18. Measuring Neuroticism in Nepali: Reliability and Validity of the Neuroticism Subscale of the Eysenck Personality Questionnaire.

    Science.gov (United States)

    Manandhar, K; Risal, A; Linde, M; Koju, R; Steiner, T J; Holen, A

    2015-01-01

    The Neuroticism subscale of the Eysenck Personality Questionnaire Revised Short Form (12 items) (EPQRS-N) has proven to be a reliable and valid measure in multiple languages. To develop a single-factor Nepali-language version of the EPQRS-N for use in the adult population of Nepal. The original English version of EPQRS-N was translated into Nepali using a forward-backward translation protocol. The first set of translated items was modified after testing by factor analysis with principal component extraction in an outpatient sample. Items with low factor correlations or poor semantic consistencies were reworded to fit the gist of the original items in a Nepali cultural context; the revised version was then tested in a representative random sample from the general population. Again, the same statistical procedures were applied. The first trial gave three factors. Based on the factor distribution of the items or their semantic quality, five were reworded. In the second trial, a two-factor solution emerged; the second factor had only one item with high correlation, which also had modest correlation with the first factor. Accordingly, a forced one-factor solution was chosen. This gave an internal consistency (Cronbach's alpha) of 0.80, with item-to-factor correlations from 0.40 to 0.73, and item-to-sum correlations from 0.31 to 0.61. The final Nepali version of EPQRS-N achieved satisfactory internal consistency. The item distribution coincided with the original English version, providing acceptable construct validity. It is psychometrically adequate for use in capturing the personality trait of neuroticism, and has broad applicability to the adult population of Nepal because of the diversity of the participant samples in which it was developed.

  19. Airspace Simulation Through Indoor Operation of Subscale Flight Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An indoor environment for simulating airspace operations will be designed. Highly maneuverable subscale vehicles can be used to simulate the dynamics of full-scale...

  20. 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.

  1. The concurrent validity of the Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale in adolescent patients in an urban federally qualified health center.

    Science.gov (United States)

    Kelly, Sharon M; O'Grady, Kevin E; Gryczynski, Jan; Mitchell, Shannon Gwin; Kirk, Arethusa; Schwartz, Robert P

    2017-01-01

    The Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale has been validated with high school students, adolescents with criminal justice involvement, and adolescent substance use treatment samples using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R and DSM-IV. This study examines the concurrent validity of the POSIT's standard 17-item substance use/abuse subscale and a revised, shorter 11-item version using DSM-5 substance use disorder diagnoses. Adolescents (N = 525; 93% African American, 55% female) 12-17 years of age awaiting primary care appointments at a Federally Qualified Health Center in Baltimore, Maryland completed the 17-item POSIT substance use/abuse subscale and items from a modified World Mental Health Composite International Diagnostic Interview corresponding to DSM-5 alcohol use disorder (AUD) and cannabis use disorder (CUD). Receiver operating characteristic curves, sensitivities, and specificities were examined with DSM-5 AUD, CUD, and a diagnosis of either or both disorders for the standard and revised subscales using risk cutoffs of either 1 or 2 POSIT "yes" responses. For the 17-item subscale, sensitivities were generally high using either cutoff (range: 0.79-1.00), although a cutoff of 1 was superior (sensitivities were 1.00 for AUD, CUD, and for either disorder). Specificities were also high using either cutoff (range: 0.81-0.95) but were higher using a cutoff of 2. For the 11-item subscale, a cutoff of 1 yielded higher sensitivities than a cutoff of 2 (ranges for 1 and 2: 0.96-1.00 and 0.79-0.86, respectively). Specificities for this subscale were higher using a cutoff of 2 (ranges for 1 and 2: 0.82-0.89 and 0.89-0.96, respectively). Findings suggest that the POSIT's substance use/abuse subscale is a potentially useful tool for screening adolescents in primary care for AUD or CUD using a cutoff of 1 or 2. The briefer, revised subscale may be preferable to the standard subscale in

  2. Development and validation of subscales to assess perceived support for self-management of mood or emotional problems: Results from a randomized trial.

    Science.gov (United States)

    McCusker, Jane; Haggerty, Jeannie; De Raad, Manon; Belzile, Eric; Bouharaoui, Fatima; Beaulieu, Christine; Yaffe, Mark; Ciampi, Antonio

    2017-06-10

    To validate 2 new patient-reported measures of self-management support from health professionals for mood and emotional problems. The sample comprised primary care patients with chronic physical conditions and co-morbid depressive symptoms enrolled in a randomized trial of telephone coaching of a depression self-care intervention (n=120). At 6-month follow-up, patients completed 2 subscales with respect to support for self-management of their chronic physical condition(s): 1) Self-Management Information (SMInfo-Phys); and 2) Care Plan (CP-Phys) and equivalent subscales adapted to assess self-management support for mood and emotional problems: SMInfo-Mood and CP-Mood. Subscale scoring was assessed with Item Response Theory (IRT) analysis. Convergent validity of the mood subscales was assessed. The sensitivity of the mood and physical condition subscales to mental health interventions was assessed with generalized estimating equations (GEE). The mood subscales were associated with relevant measures of perceived unmet mental health needs. Both SMInfo-Mood and CP-Mood were sensitive to the coaching intervention; CP-Mood was also sensitive to receipt of depression treatment outside the trial. This study provides preliminary evidence for the validity of the 2 new subscales. The subscales may be used to assess perceived health professional support for self-management of mood and emotional problems. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Subscale Water Based Phase Change Material Heat Exchanger Development

    Science.gov (United States)

    Sheth, Rubik; Hansen, Scott

    2016-01-01

    Supplemental heat rejection devices are required in many spacecraft as the radiators are not sized to meet the full heat rejection demand. One means of obtaining additional heat rejection is through the use of phase change material heat exchangers (PCM HX's). PCM HX's utilize phase change to store energy in unfavorable thermal environments (melting) and reject the energy in favorable environments (freezing). Traditionally, wax has been used as a PCM on spacecraft. However, water is an attractive alternative because it is capable of storing about 40% more energy per unit mass due to its higher latent heat of fusion. The significant problem in using water as a PCM is its expansion while freezing, leading to structural integrity concerns when housed in an enclosed heat exchanger volume. Significant investigation and development has taken place over the past five years to understand and overcome the problems associated with water PCM HX's. This paper reports on the final efforts by Johnson Space Center's Thermal Systems Branch to develop a water based PCM HX. The test article developed and reported on is a subscale version of the full-scale water-based PCM HX's constructed by Mezzo Technologies. The subscale unit was designed by applying prior research on freeze front propagation and previous full-scale water PCM HX development. Design modifications to the subscale unit included use of urethane bladder, decreased aspect ratio, perforated protection sheet, and use of additional mid-plates. Testing of the subscale unit was successful and 150 cycles were completed without fail.

  4. Subscales of the Barratt Impulsiveness Scale differentially relate to the Big Five factors of personality.

    Science.gov (United States)

    Lange, Florian; Wagner, Adina; Müller, Astrid; Eggert, Frank

    2017-06-01

    The place of impulsiveness in multidimensional personality frameworks is still unclear. In particular, no consensus has yet been reached with regard to the relation of impulsiveness to Neuroticism and Extraversion. We aim to contribute to a clearer understanding of these relationships by accounting for the multidimensional structure of impulsiveness. In three independent studies, we related the subscales of the Barratt Impulsiveness Scale (BIS) to the Big Five factors of personality. Study 1 investigated the associations between the BIS subscales and the Big Five factors as measured by the NEO Five-Factor Inventory (NEO-FFI) in a student sample (N = 113). Selective positive correlations emerged between motor impulsiveness and Extraversion and between attentional impulsiveness and Neuroticism. This pattern of results was replicated in Study 2 (N = 132) using a 10-item short version of the Big Five Inventory. In Study 3, we analyzed BIS and NEO-FFI data obtained from a sample of patients with pathological buying (N = 68). In these patients, the relationship between motor impulsiveness and Extraversion was significantly weakened when compared to the non-clinical samples. At the same time, the relationship between attentional impulsiveness and Neuroticism was substantially stronger in the clinical sample. Our studies highlight the utility of the BIS subscales for clarifying the relationship between impulsiveness and the Big Five personality factors. We conclude that impulsiveness might occupy multiple places in multidimensional personality frameworks, which need to be specified to improve the interpretability of impulsiveness scales. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  5. Energy Cascade Analysis: from Subscale Eddies to Mean Flow

    Science.gov (United States)

    Cheikh, Mohamad Ibrahim; Wonnell, Louis; Chen, James

    2017-11-01

    Understanding the energy transfer between eddies and mean flow can provide insights into the energy cascade process. Much work has been done to investigate the energy cascade at the level of the smallest eddies using different numerical techniques derived from the Navier-Stokes equations. These methodologies, however, prove to be computationally inefficient when producing energy spectra for a wide range of length scales. In this regard, Morphing Continuum Theory (MCT) resolves the length-scales issues by assuming the fluid continuum to be composed of inner structures that play the role of subscale eddies. The current study show- cases the capabilities of MCT in capturing the dynamics of energy cascade at the level of subscale eddies, through a supersonic turbulent flow of Mach 2.93 over an 8× compression ramp. Analysis of the results using statistical averaging procedure shows the existence of a statistical coupling of the internal and translational kinetic energy fluctuations with the corresponding rotational kinetic energy of the subscale eddies, indicating a multiscale transfer of energy. The results show that MCT gives a new characterization of the energy cascade within compressible turbulence without the use of excessive computational resources. This material is based upon work supported by the Air Force Office of Scientific Research under Award Number FA9550-17-1-0154.

  6. Childhood depression subscales using repeated sessions on Children's Depression Rating Scale - revised (CDRS-R) scores.

    Science.gov (United States)

    Isa, Ameena; Bernstein, Ira; Trivedi, Madhukar; Mayes, Taryn; Kennard, Betsy; Emslie, Graham

    2014-08-01

    Although acute treatments have been shown to be effective in treating early-onset depression, only one-third or thereabouts reach a remission within 3 months. Unfortunately, delayed time to remission in early-onset depression leads to poorer therapeutic outcomes. Clearly, there is a need to identify, diagnose, and provide effective treatment of a depressed patient quickly. A sophisticated understanding of depression subscales and their change over time with treatment could enhance pathways to individualized treatment approaches for childhood depression. Previous studies have found that the clinician-measured instrument, Children's Depression Rating Scale-Revised (CDRS-R) measures multiple subscales (or components) of depression. The aim of this study was to see how these subscales may change over the course of a 12-week study. This knowledge will help determine if dimensions/subscales of childhood depression (paralleling the adult literature) using the subscales derived from factor analysis procedure is useful. We examined two clinical trials in which youth (n=234) with major depressive disorder (MDD) were treated openly with fluoxetine for eight sessions spread over 12 weeks. The CDRS-R was completed based on clinician interviews with parent and child at each session. Classical test theory and component analysis with associated parallel analysis (oblique rotation) were conducted on each week's scores. Although more factors were needed for the baseline and first two therapy sessions, a two-factor solution sufficed thereafter. Depressed facial affect, listless speech, and hypoactivity best defined Factor I, whereas sleep problems, appetite disturbance, physical symptoms, irritability, guilt, and weeping best defined Factor II. All other symptoms cross-loaded almost equally on the two factors. The scale's reliability (internal consistency) improved from baseline to exit sessions (α=0.65-0.91). As a result, the clinicians' assessments of the various symptoms became

  7. Changes to the subscales of two vision-related quality of life questionnaires are proposed.

    Science.gov (United States)

    de Boer, Michiel R; de Vet, Henrica C W; Terwee, Caroline B; Moll, Annette C; Völker-Dieben, Hennie J M; van Rens, Ger H M B

    2005-12-01

    Psychometrically sound questionnaires for the assessment of vision-related quality of life (QOL) are scarce. Therefore, the objective was to further validate two vision-related QOL questionnaires in a Dutch population of visually impaired elderly. A total of 329 visually impaired older persons referred to low vision services completed the low vision QOL (LVQOL) and Vision-Related Quality of Life Core Measure (VCM1) questionnaires at baseline, after 1-4 weeks (retest), and after 5 months. Confirmatory factor analyses were performed on baseline data. The smallest detectable change (SDC) was assessed, based on the standard error of measurement (SEM). Change scores between the baseline and 5 months follow-up data were related to a general transition question to assess the minimal important change (MIC). Furthermore, the MIC was related to the SDC, to examine whether the MICs were detectable beyond measurement error. The original factor structures could not be confirmed. After omitting items and remodeling, adequate fits were obtained. SDCs comprised at least one quarter of the scale for all scales and subscales on the individual level and exceeded the MICs on every occasion. We propose MICs of 5-10 points for the scales and subscales of the LVQOL and VCM1. The questionnaires are not useful in the follow-up of individual patients.

  8. Revisiting the internal consistency and factorial validity of the 8-item Morisky Medication Adherence Scale.

    Science.gov (United States)

    Zongo, Arsène; Guénette, Line; Moisan, Jocelyne; Guillaumie, Laurence; Lauzier, Sophie; Grégoire, Jean-Pierre

    2016-01-01

    To assess the internal consistency and factorial validity of the adapted French 8-item Morisky Medication Adherence Scale in assessing adherence to noninsulin antidiabetic drug treatment. In a cross-sectional web survey of individuals with type 2 diabetes of the Canadian province of Quebec, self-reported adherence to the antidiabetes drug treatment was measured using the Morisky Medication Adherence Scale-8. We assessed the internal consistency of the Morisky Medication Adherence Scale-8 with Cronbach's alpha, and factorial validity was assessed by identifying the underlying factors using exploratory factor analyses. A total of 901 individuals completed the survey. Cronbach's alpha was 0.60. Two factors were identified. One factor comprised five items: stopping medication when diabetes is under control, stopping when feeling worse, feeling hassled about sticking to the prescription, reasons other than forgetting and a cross-loading item (i.e. taking drugs the day before). The second factor comprised three other items that were all related to forgetfulness in addition to the cross-loading item. Cronbach's alpha of the adapted French Morisky Medication Adherence Scale-8 was below the acceptable value of 0.70. This observed low internal consistency of the scale is probably related to the causal nature of the items of the scale but not necessarily a lack of reliability. The results suggest that the adapted French Morisky Medication Adherence Scale-8 is a two-factor scale assessing intentional (first factor) and unintentional (second factor) non-adherence to the noninsulin antidiabetes drug treatment. The scale could be used to separately identify these outcomes using scores obtained on each of the sub-scales.

  9. Description and Operation of the A3 Subscale Facility

    Science.gov (United States)

    Saunders, G. P.; Varner, D. G.; Grover, J. B.

    2010-01-01

    The purpose of this paper is to give an overview of the general design and operation of the A3 Subscale test facility. The goal is to provide the reader with a general understanding of what the major facility systems are, where they are located, and how they are used to meet the objectives supporting the design of the A3 altitude rocket test facility. This paper also provides the reader with the background information prior to reading the subsequent papers detailing the design and test results of the various systems described herein.

  10. Factor Analysis of Multidimensional Polytomous Item Response Data Suffering from Ignorable Item Nonresponse.

    Science.gov (United States)

    Bernaards A., Coen; Sijtsma, Klaas

    1999-01-01

    Used simulation to study the problem of missing item responses in tests and questionnaires when factor analysis is used to study the structure of the items. Factor loadings based on the EM algorithm best approximated the loading structure, with imputation of the mean per person across the scores for that person being the best alternative. (SLD)

  11. 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.

  12. Psychometric properties of the Arabic version of the 12-item diabetes fatalism scale.

    Directory of Open Access Journals (Sweden)

    Ola Sukkarieh-Haraty

    Full Text Available There are widespread fatalistic beliefs in Arab countries, especially among individuals with diabetes. However, there is no tool to assess diabetes fatalism in this population. This study describes the processes used to create an Arabic version of the Diabetes Fatalism Scale (DFS and examine its psychometric properties.A descriptive correlational design was used with a convenience sample of Lebanese adults (N = 274 with type 2 diabetes recruited from a major hospital in Beirut, Lebanon and by snowball sampling. The 12- item Diabetes Fatalism Scale- Arabic (12-item DFS-Ar was back-translated from the original version, pilot tested on 22 adults with type 2 diabetes and then administered to 274 patients to assess the validity and reliability of the scale. Confirmatory factor analysis (CFA was used to test the hypothesized factor structure. Cronbach's alpha was used to test for reliability.CFA supported the existence of the three factor hypothesis of the original DFS scale. The five items measuring "emotional distress" loaded under Factor 1, the four items measuring "spiritual coping" loaded under factor 2 and the last three items measuring "perceived self-efficacy" of the original scale loaded under Factor 3 (p <0.001 for all three subscales. Goodness of fit indices confirmed adequateness of the CFA model (CFI = 0.97, TLI = 0.96, RMSEA = 0.067 and pclose = 0.05. The 12-item DFS-Ar showed good reliability (Cronbach's alpha of 0.86 and significantly predicted HbA1c (β = 0.20, p < 0.01. After adjusting for the demographic characteristics and the number of diabetes comorbid conditions, the 12-item DFS-Ar score was independently associated with HbA1c in a multivariable model (β = 0.16, p < 0.05.The 12-item DFS-Ar demonstrated good psychometric properties that are comparable to the original scale. It is a valid and reliable measure of diabetes fatalism. Further testing with larger and non-Lebanese Arabic population is needed.

  13. The technology - activities of daily living questionnaire: a version with a technology-related subscale.

    Science.gov (United States)

    Muñoz-Neira, Carlos; López, Oscar L; Riveros, Rodrigo; Núñez-Huasaf, Javier; Flores, Patricia; Slachevsky, Andrea

    2012-01-01

    Information and communication technology (ICT) has become an increasingly important part of daily life. The ability to use technology is becoming essential for autonomous functioning in society. Current functional scales for patients with cognitive impairment do not evaluate the use of technology. The objective of this study was to develop and validate a new version of the Activities of Daily Living Questionnaire (ADLQ) that incorporates an ICT subscale. A new technology-based subscale was incorporated into the Spanish version of the ADLQ (SV-ADLQ), entitled the Technology version of the ADLQ (T-ADLQ). The T-ADLQ was administered to 63 caregivers of dementia patients, 21 proxies of mild cognitive impairment patients and 44 proxies of normal elderly subjects (mean age of the sample ± SD: 73.5 ± 8.30 years). We analysed the convergent validity, internal consistency, reliability cut-off point, sensitivity and specificity of the T-ADLQ. The results of the T-ADLQ were compared to the SV-ADLQ. The T-ADLQ showed significant correlations with the Mini-Mental State Examination (MMSE), the Frontal Assessment Battery (FAB) as well as other measures of functional impairment and dementia severity (MMSE: r = -0.70; FAB: r = -0.65; Functional Assessment Questionnaire: r = 0.77; Instrumental Activities of Daily Living Scale: r = -0.75; Clinical Dementia Rating Scale: r = 0.72; p questions to the ADLQ, our experience suggested that this has to be done cautiously, since the sensitivity of these additional items could vary in different populations. The T-ADLQ needs to be validated in a different population of dementia subjects. Copyright © 2012 S. Karger AG, Basel.

  14. Prevalence of item level negative symptoms in first episode psychosis diagnoses.

    LENUS (Irish Health Repository)

    Lyne, John

    2012-03-01

    The relevance of negative symptoms across the diagnostic spectrum of the psychoses remains uncertain. The purpose of this study was to report on prevalence of item and subscale level negative symptoms across the first episode psychosis (FEP) diagnostic spectrum in an epidemiological sample, and to ascertain whether items and subscales were more prevalent in a schizophrenia spectrum diagnoses group compared to an \\'all other psychotic diagnoses\\' group. We measured negative symptoms in 330 patients presenting with FEP using the Scale for Assessment of Negative Symptoms (SANS), and ascertained diagnosis using the Structured Clinical Interview for DSM IV. Prevalence of SANS items and subscales were tabulated across all psychotic diagnoses, and logistic regression analysis determined which items and subscales were predictive of schizophrenia spectrum diagnoses. SANS items were most prevalent in schizophrenia spectrum conditions but frequently presented in other FEP diagnoses, particularly substance induced psychotic disorder and Major Depressive Disorder. Brief psychotic disorder and bipolar disorders had low levels of negative symptoms. SANS items and subscales which significantly predicted schizophrenia spectrum diagnoses, were also frequently present in some of the other psychotic diagnoses. Conclusions: SANS items have high prevalence in FEP, and while commonest in schizophrenia spectrum conditions are not restricted to this diagnostic subgroup.

  15. 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

    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...

  16. Automated Item Selection Using Item Response Theory.

    Science.gov (United States)

    Stocking, Martha L.; And Others

    This paper presents a new heuristic approach to interactive test assembly that is called the successive item replacement algorithm. This approach builds on the work of W. J. van der Linden (1987) and W. J. van der Linden and E. Boekkooi-Timminga (1989) in which methods of mathematical optimization are combined with item response theory to…

  17. SPE5 Sub-Scale Test Series Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, Kevin S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reeves, Robert V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DeHaven, Martin R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strickland, Shawn L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-14

    A series of 2 SPE5 sub-scale tests were performed to experimentally confirm that a booster system designed and evaluated in prior tests would properly initiate the PBXN-110 case charge fill. To conduct the experiments, a canister was designed to contain the nominally 50 mm diameter booster tube with an outer fill of approximately 150 mm diameter by 150 mm in length. The canisters were filled with PBXN-110 at NAWS-China Lake and shipped back to LLNL for testing in the High Explosives Applications Facility (HEAF). Piezoelectric crystal pins were placed on the outside of the booster tube before filling, and a series of piezoelectric crystal pins along with Photonic Doppler Velocimetry (PDV) probes were placed on the outer surface of the canister to measure the relative timing and magnitude of the detonation. The 2 piezoelectric crystal pins integral to the booster design were also utilized along with a series of either piezoelectric crystal pins or piezoelectric polymer pads on the top of the canister or outside case that utilized direct contact, gaps, or different thicknesses of RTV cushions to obtain time of arrival data to evaluate the response in preparation for the large-scale SPE5 test. To further quantify the margin of the booster operation, the 1st test (SPE5SS1) was functioned with both detonators and the 2nd test (SPE5SS2) was functioned with only 1 detonator. A full detonation of the material was observed in both experiments as observed by the pin timing and PDV signals. The piezoelectric pads were found to provide a greater measured signal magnitude during the testing with an RTV layer present, and the improved response is due to the larger measurement surface area of the pad. This report will detail the experiment design, canister assembly for filling, final assembly, experiment firing, presentation of the diagnostic results, and a discussion of the results.

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    Pollard Beth

    2012-12-01

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

  20. Helium-Cooled Black Shroud for Subscale Cryogenic Testing

    Science.gov (United States)

    Tuttle, James; Jackson, Michael; DiPirro, Michael; Francis, John

    2011-01-01

    This shroud provides a deep-space simulating environment for testing scaled-down models of passively cooling systems for spaceflight optics and instruments. It is used inside a liquid-nitrogen- cooled vacuum chamber, and it is cooled by liquid helium to 5 K. It has an inside geometry of approximately 1.6 m diameter by 0.45 m tall. The inside surfaces of its top and sidewalls have a thermal absorptivity greater than 0.96. The bottom wall has a large central opening that is easily customized to allow a specific test item to extend through it. This enables testing of scale models of realistic passive cooling configurations that feature a very large temperature drop between the deepspace-facing cooled side and the Sun/Earth-facing warm side. This shroud has an innovative thermal closeout of the bottom wall, so that a test sample can have a hot (room temperature) side outside of the shroud, and a cold side inside the shroud. The combination of this closeout and the very black walls keeps radiated heat from the sample s warm end from entering the shroud, reflecting off the walls and heating the sample s cold end. The shroud includes 12 vertical rectangular sheet-copper side panels that are oriented in a circular pattern. Using tabs bent off from their edges, these side panels are bolted to each other and to a steel support ring on which they rest. The removable shroud top is a large copper sheet that rests on, and is bolted to, the support ring when the shroud is closed. The support ring stands on four fiberglass tube legs, which isolate it thermally from the vacuum chamber bottom. The insides of the cooper top and side panels are completely covered with 25- mm-thick aluminum honeycomb panels. This honeycomb is painted black before it is epoxied to the copper surfaces. A spiral-shaped copper tube, clamped at many different locations to the outside of the top copper plate, serves as part of the liquid helium cooling loop. Another copper tube, plumbed in a series to the

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

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

    NARCIS (Netherlands)

    Scott, N.W.; Fayers, P.M.; Aaronson, N.K.; Bottomley, A.; de Graeff, A.; Groenvold, M.; Gundy, C.; Koller, M.; Petersen, M.A.; Sprangers, M.A.G.

    2010-01-01

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

  3. Examining unidimensionality and improving reliability for the eight subscales of the SF-36 in opioid-dependent patients using Rasch analysis.

    Science.gov (United States)

    Hsiao, Yu-Yu; Shih, Ching-Lin; Yu, Wan-Hui; Hsieh, Cheng-Hsi; Hsieh, Ching-Lin

    2015-02-01

    The Medical Outcome Study Short Form 36 (SF-36) is one of the most commonly used questionnaires for monitoring the Health-Related Quality of Life (HRQOL) of opioid-dependent patients. However, the unidimensionality and reliability of the SF-36 have not been verified in opioid-dependent patients. The aim of this study was to examine the unidimensionality and to improve the test reliability of the SF-36 for use in opioid-dependent patients. A total of 583 opioid-dependent patients were recruited in the study. Unidimensionality was examined by conducting unidimensional Rasch analysis. Item fit statistics and principle component analysis were used to check the item-model fit in each of the eight subscales of the SF-36. Reliability was evaluated by applying both unidimensional and multidimensional Rasch analyses. After three misfitting items were excluded, the remaining items of each subscale in the SF-36 represented a single construct. The test reliabilities (0.80-0.87) yielded by the multidimensional approach were much higher than those (0.68-0.82) produced by the unidimensional approach. The remaining 32 items of the SF-36 are appropriate for evaluating the HRQOL in opioid-dependent patients in terms of unidimensionality. Additionally, the test scores produced by the multidimensional approach were more accurate than those obtained by the unidimensional approach.

  4. Separating the Domains of Oppositional Behavior: Comparing Latent Models of the Conners’ Oppositional Subscale

    Science.gov (United States)

    Kuny, Ana V.; Althoff, Robert R.; Copeland, William; Bartels, Meike; Beijsterveldt, Van; Baer, Julie; Hudziak, James J.

    2012-01-01

    OBJECTIVE Although Oppositional Defiant Disorder (ODD) is usually considered the mildest of the disruptive behavior disorders, it is a key factor in predicting young adult anxiety and depression and is distinguishable from normal childhood behavior. In an effort to understand possible subsets of oppositional defiant behavior (ODB) which may differentially predict outcome, we used Latent Class Analysis (LCA) of mother’s report on the Conners’ Parent Rating Scales Revised Short Forms (CPRS-R:S). METHOD Data were obtained from mother’s report for Dutch twins (7 year-old [n = 7,597], 10 year-old [n = 6,548], and 12 year-old [n = 5,717]) from the Netherlands Twin Registry. Samples partially overlapped at ages 7 and 10 (19% overlapping) and at ages 10 and 12 (30% overlapping), but not at ages 7 and 12. Oppositional defiant behavior was measured using the 6-item Oppositional subscale of the CPRS-R:S. Multilevel LCA with robust standard error estimates was performed using Latent Gold to control for twin-twin dependence in the data. Class assignment across ages was determined and an estimate of heritability for each class was calculated. Comparisons to maternal report Child Behavior Checklist (CBCL) scores were examined using linear mixed models at each age, corrected for multiple comparisons. RESULTS The LCA identified an optimal solution of 4-classes across age groups: Class 1 was associated with no or low symptom endorsement (69–75% of the children), class 2 was characterized by defiance (11–12%), class 3 was characterized by irritability (9–11%), and class 4 was associated with elevated scores on all symptoms (5–8%). Odds ratios for twins being in the same class at each successive age point were higher within classes across ages than between classes. Heritability within the two “intermediate” classes was nearly as high as for the class with all symptoms, except for boys at age 12. Children in the Irritable Class were more likely to have mood symptoms

  5. Applying posttraumatic stress disorder MMPI subscale to World War II POW veterans.

    Science.gov (United States)

    Query, W T; Megran, J; McDonald, G

    1986-03-01

    In order to determine whether the MMPI-PTSD subscale has application for assessing DSM-III diagnosed PTSD among populations other than Vietnam veterans, a group of WWII POWs (N = 69) were given the subscale. Results indicated that the use of the PTSD subscale can be generalized to older veterans; in a small sample of Pacific POWs, PTSD is more common among those from the Pacific theater than those from Europe. However, the subscale fails to distinguish between Pacific and European POW veterans. Difficulties in sampling and confounding stressors are discussed, as well as implications for treatment of WWII veterans.

  6. Spearman's hypothesis tested comparing Libyan adults with various other groups of adults on the items of the Standard Progressive Matrices

    NARCIS (Netherlands)

    te Nijenhuis, J.; Al-Shahomee, A.A.; van den Hoek, M.; Grigoriev, A.; Repko, J.

    2015-01-01

    Spearman's hypothesis tested at the level of items states that differences between groups on the items of an IQ test are a function of the g loadings of these items, such that there are small differences between groups on items with low g loadings and large differences between groups on items with

  7. Subscale and Full-Scale Testing of Buckling-Critical Launch Vehicle Shell Structures

    Science.gov (United States)

    Hilburger, Mark W.; Haynie, Waddy T.; Lovejoy, Andrew E.; Roberts, Michael G.; Norris, Jeffery P.; Waters, W. Allen; Herring, Helen M.

    2012-01-01

    New analysis-based shell buckling design factors (aka knockdown factors), along with associated design and analysis technologies, are being developed by NASA for the design of launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s launch vehicle development and performance risks by reducing the reliance on testing, providing high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale level. This paper describes recent buckling test efforts at NASA on two different orthogrid-stiffened metallic cylindrical shell test articles. One of the test articles was an 8-ft-diameter orthogrid-stiffened cylinder and was subjected to an axial compression load. The second test article was a 27.5-ft-diameter Space Shuttle External Tank-derived cylinder and was subjected to combined internal pressure and axial compression.

  8. Measurement of aggressive behaviors in dementia: comparison of the physical aggression subscales of the Cohen-Mansfield Agitation Inventory and the Ryden Aggression Scale.

    Science.gov (United States)

    Whall, Ann L; Kim, Hyojeong; Colling, Kathleen Byrne; Hong, Gwi-Ryung; DeCicco, Barry; Antonakos, Cathy

    2013-07-01

    One of the central issues in the development of research-based interventions for aggressive behavior (AB) in late-stage dementia is the provision of precise measurement of the major dependent variable, in this case, AB levels. To advance the nursing goal of evidence-based practice, this article presents the characteristics of two research instruments: the Cohen-Mansfield Agitation Inventory (CMAI) aggressive behavior subscale (CMAI-ABS) and the Ryden Aggression Scale (RAS) physically aggressive behavior subscale (RAS-PABS). A total of 282 shower bath events (which are most associated with AB) were observed for 107 nursing home residents with dementia in nine randomly selected nursing homes. Then, we compared the psychometric properties of the CMAI-ABS and the RAS-PABS. Moderate to substantial agreements between the two instruments were identified using Cohen's Kappa. A similar percentage of AB was found on both subscales. Similar items on both subscales, such as hitting and pushing, were moderately correlated. Overall, the study results support that the CMAI-ABS and RAS-PABS measure a single but multifaceted construct-physically aggressive behavior in dementia. Copyright 2013, SLACK Incorporated.

  9. Classification of quality of life subscales within the ICF framework in burn research: identifying overlaps and gaps.

    Science.gov (United States)

    Meirte, J; van Loey, N E E; Maertens, K; Moortgat, P; Hubens, G; Van Daele, U

    2014-11-01

    Quality of life (QOL) is one of the leading outcomes in burn care research. This study classifies subscales of common QOL measures within the International Classification of Functioning disability and health (ICF) framework to determine to which extent the measures are complementary or overlapping and to investigate whether the instruments are able to describe the full spectrum of patients' functioning. A literature search was performed to determine the most frequently used questionnaires in burn research. The subscales of the three mostly used questionnaires were classified within the ICF framework. Two generic measures, the Short Form-36 items (SF-36) and the European Quality of Life 5 Dimensions (EQ-5D), and a disease specific measure, the Burn Specific Health Scale-Brief (BSHS-B), were analyzed. The BSHS-B covered most domains and was the only scale that included personal factors. The SF-36 included only one domain in the activity limitations and similar to the EQ-5D no contextual factors were included. Environmental factors were not addressed in the questionnaires, even though these may have an impact on the quality of life in patients with burns. To capture the full spectrum of dysfunctioning a combination of the BSHS-B with a generic questionnaire seems obligatory. However still some domains of functioning remain uncovered. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  10. Increasing the Precision of Subscale Scores by Using Out-of-Scale Information

    Science.gov (United States)

    Kahraman, Nilufer; Kamata, Akihito

    2004-01-01

    In this study, the precision of subscale score estimates was evaluated when out-of-scale information was incorporated. Procedures that incorporated out-of-scale information and only information within a subscale were compared through a series of simulations. It was revealed that more information (i.e., more precision) was always provided for…

  11. Vegetable parenting practices scale. Item response modeling analyses.

    Science.gov (United States)

    Chen, Tzu-An; O'Connor, Teresia M; Hughes, Sheryl O; Beltran, Alicia; Baranowski, Janice; Diep, Cassandra; Baranowski, Tom

    2015-08-01

    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 also tested for differences in the ways item function (called differential item functioning) across child's gender, ethnicity, age, and household income groups. Parents of 3-5 year old children completed a self-reported vegetable parenting practices scale online. Vegetable parenting practices consisted of 14 effective vegetable parenting practices and 12 ineffective vegetable parenting practices items, each with three subscales (responsiveness, structure, and control). Multidimensional polytomous item response modeling was conducted separately on effective vegetable parenting practices and ineffective vegetable parenting practices. One effective vegetable parenting practice item did not fit the model well in the full sample or across demographic groups, and another was a misfit in differential item functioning analyses across child's gender. Significant differential item functioning was detected across children's age and ethnicity groups, and more among effective vegetable parenting practices than ineffective vegetable parenting practices items. Wright maps showed items only covered parts of the latent trait distribution. The harder- and easier-to-respond ends of the construct were not covered by items for effective vegetable parenting practices and ineffective vegetable parenting practices, respectively. Several effective vegetable parenting practices and ineffective vegetable parenting practices scale items functioned differently on the basis of child's demographic characteristics; therefore, researchers should use these vegetable parenting practices scales with caution. Item response modeling should be incorporated in analyses of parenting practice questionnaires to better assess

  12. Fatigue life prediction of liquid rocket engine combustor with subscale test verification

    Science.gov (United States)

    Sung, In-Kyung

    Reusable rocket systems such as the Space Shuttle introduced a new era in propulsion system design for economic feasibility. Practical reusable systems require an order of magnitude increase in life. To achieve this improved methods are needed to assess failure mechanisms and to predict life cycles of rocket combustor. A general goal of the research was to demonstrate the use of subscale rocket combustor prototype in a cost-effective test program. Life limiting factors and metal behaviors under repeated loads were surveyed and reviewed. The life prediction theories are presented, with an emphasis on studies that used subscale test hardware for model validation. From this review, low cycle fatigue (LCF) and creep-fatigue interaction (ratcheting) were identified as the main life limiting factors of the combustor. Several life prediction methods such as conventional and advanced viscoplastic models were used to predict life cycle due to low cycle thermal stress, transient effects, and creep rupture damage. Creep-fatigue interaction and cyclic hardening were also investigated. A prediction method based on 2D beam theory was modified using 3D plate deformation theory to provide an extended prediction method. For experimental validation two small scale annular plug nozzle thrusters were designed, built and tested. The test article was composed of a water-cooled liner, plug annular nozzle and 200 psia precombustor that used decomposed hydrogen peroxide as the oxidizer and JP-8 as the fuel. The first combustor was tested cyclically at the Advanced Propellants and Combustion Laboratory at Purdue University. Testing was stopped after 140 cycles due to an unpredicted failure mechanism due to an increasing hot spot in the location where failure was predicted. A second combustor was designed to avoid the previous failure, however, it was over pressurized and deformed beyond repair during cold-flow test. The test results are discussed and compared to the analytical and numerical

  13. Sensitivity to changes during antidepressant treatment: a comparison of unidimensional subscales of the Inventory of Depressive Symptomatology (IDS-C) and the Hamilton Depression Rating Scale (HAMD) in patients with mild major, minor or subsyndromal depression.

    Science.gov (United States)

    Helmreich, Isabella; Wagner, Stefanie; Mergl, Roland; Allgaier, Antje-Kathrin; Hautzinger, Martin; Henkel, Verena; Hegerl, Ulrich; Tadić, André

    2012-06-01

    In the efficacy evaluation of antidepressant treatments, the total score of the Hamilton Depression Rating Scale (HAMD) is still regarded as the 'gold standard'. We previously had shown that the Inventory of Depressive Symptomatology (IDS) was more sensitive to detect depressive symptom changes than the HAMD17 (Helmreich et al. 2011). Furthermore, studies suggest that the unidimensional subscales of the HAMD, which capture the core depressive symptoms, outperform the full HAMD regarding the detection of antidepressant treatment effects. The aim of the present study was to compare several unidimensional subscales of the HAMD and the IDS regarding their sensitivity to changes in depression symptoms in a sample of patients with mild major, minor or subsyndromal depression (MIND). Biweekly IDS-C28 and HAMD17 data from 287 patients of a 10-week randomised, placebo-controlled trial comparing the effectiveness of sertraline and cognitive-behavioural group therapy in patients with MIND were converted to subscale scores and analysed during the antidepressant treatment course. We investigated sensitivity to depressive change for all scales from assessment-to-assessment, in relation to depression severity level and placebo-verum differences. The subscales performed similarly during the treatment course, with slight advantages for some subscales in detecting treatment effects depending on the treatment modality and on the items included. Most changes in depressive symptomatology were detected by the IDS short scale, but regarding the effect sizes, it performed worse than most subscales. Unidimensional subscales are a time- and cost-saving option in judging drug therapy outcomes, especially in antidepressant treatment efficacy studies. However, subscales do not cover all facets of depression (e.g. atypical symptoms, sleep disturbances), which might be important for comprehensively understanding the nature of the disease depression. Therefore, the cost-to-benefit ratio must be

  14. Psychometric properties of the Centers for Disease Control and Prevention Health-Related Quality of Life (CDC HRQOL items in adults with arthritis

    Directory of Open Access Journals (Sweden)

    DeVellis Robert

    2006-09-01

    Full Text Available Abstract Background Measuring health-related quality of life (HRQOL is important in arthritis and the SF-36v2 is the current state-of-the-art. It is only emerging how well the Centers for Disease Control and Prevention (CDC HRQOL measures HRQOL for people with arthritis. This study's purpose is to assess the psychometric properties of the 9-item CDC HRQOL (4-item Healthy Days Core Module and 5-item Healthy Days Symptoms Module in an arthritis sample using the SF-36v2 as a comparison. Methods In Fall 2002, a cross-sectional study acquired survey data including the CDC HRQOL and SF-36v2 from 2 North Carolina populations of adult patients reporting osteoarthritis, rheumatoid arthritis, and fibromyalgia; 2182 (52% responded. The first item of both the CDC HRQOL and the SF-36v2 was general health (GEN. All 8 other CDC HRQOL items ask for the number of days in the past 30 days that respondents experienced various aspects of HRQOL. Exploratory principal components analyses (PCA were conducted on each sample and the combined samples of the CDC HRQOL. The multitrait-multimethod matrix (MTMM was used to compute correlations between each trait (physical health and mental health and between each method of measurement (CDC HRQOL and SF36v2. The relative contribution of the CDC HRQOL in predicting the physical component summary (PCS and the mental component summary (MCS was determined by regressing the CDC HRQOL items on the PCS and MCS scales. Results All 9 CDC HRQOL items loaded primarily onto 1 factor (explaining 57% of the item variance representing a reasonable solution for capturing overall HRQOL. After rotation a 2 factor interpretation for the 9 items was clear, with 4 items capturing physical health (physical, activity, pain, and energy days and 3 items capturing mental health (mental, depression, and anxiety days. All of the loadings for these two factors were greater than 0.70. The CDC HRQOL physical health factor correlated with PCS (r = -.78, p 2

  15. An item response theory analysis of the narcissistic personality inventory.

    Science.gov (United States)

    Ackerman, Robert A; Donnellan, M Brent; Robins, Richard W

    2012-01-01

    This research uses item response theory methods to evaluate the Narcissistic Personality Inventory (NPI; Raskin & Terry, 1988). Analyses using the 2-parameter logistic model were conducted on the total score and the Corry, Merritt, Mrug, and Pamp (2008) and Ackerman et al. (2011) subscales for the NPI. In addition to offering precise information about the psychometric properties of the NPI item pool, these analyses generated insights that can be used to develop new measures of the personality constructs embedded within this frequently used inventory.

  16. The 12 item Social and Economic Conservatism Scale (SECS.

    Directory of Open Access Journals (Sweden)

    Jim A C Everett

    Full Text Available Recent years have seen a surge in psychological research on the relationship between political ideology (particularly conservatism and cognition, affect, behaviour, and even biology. Despite this flurry of investigation, however, there is as yet no accepted, validated, and widely used multi-item scale of conservatism that is concise, that is modern in its conceptualisation, and that includes both social and economic conservatism subscales. In this paper the 12-Item Social and Economic Conservatism Scale (SECS is proposed and validated to help fill this gap. The SECS is suggested to be an important and useful tool for researchers working in political psychology.

  17. Towards parsimony in habit measurement: Testing the convergent and predictive validity of an automaticity subscale of the Self-Report Habit Index

    Science.gov (United States)

    2012-01-01

    Background The twelve-item Self-Report Habit Index (SRHI) is the most popular measure of energy-balance related habits. This measure characterises habit by automatic activation, behavioural frequency, and relevance to self-identity. Previous empirical research suggests that the SRHI may be abbreviated with no losses in reliability or predictive utility. Drawing on recent theorising suggesting that automaticity is the ‘active ingredient’ of habit-behaviour relationships, we tested whether an automaticity-specific SRHI subscale could capture habit-based behaviour patterns in self-report data. Methods A content validity task was undertaken to identify a subset of automaticity indicators within the SRHI. The reliability, convergent validity and predictive validity of the automaticity item subset was subsequently tested in secondary analyses of all previous SRHI applications, identified via systematic review, and in primary analyses of four raw datasets relating to energy‐balance relevant behaviours (inactive travel, active travel, snacking, and alcohol consumption). Results A four-item automaticity subscale (the ‘Self-Report Behavioural Automaticity Index’; ‘SRBAI’) was found to be reliable and sensitive to two hypothesised effects of habit on behaviour: a habit-behaviour correlation, and a moderating effect of habit on the intention-behaviour relationship. Conclusion The SRBAI offers a parsimonious measure that adequately captures habitual behaviour patterns. The SRBAI may be of particular utility in predicting future behaviour and in studies tracking habit formation or disruption. PMID:22935297

  18. Towards parsimony in habit measurement: testing the convergent and predictive validity of an automaticity subscale of the Self-Report Habit Index.

    Science.gov (United States)

    Gardner, Benjamin; Abraham, Charles; Lally, Phillippa; de Bruijn, Gert-Jan

    2012-08-30

    The twelve-item Self-Report Habit Index (SRHI) is the most popular measure of energy-balance related habits. This measure characterises habit by automatic activation, behavioural frequency, and relevance to self-identity. Previous empirical research suggests that the SRHI may be abbreviated with no losses in reliability or predictive utility. Drawing on recent theorising suggesting that automaticity is the 'active ingredient' of habit-behaviour relationships, we tested whether an automaticity-specific SRHI subscale could capture habit-based behaviour patterns in self-report data. A content validity task was undertaken to identify a subset of automaticity indicators within the SRHI. The reliability, convergent validity and predictive validity of the automaticity item subset was subsequently tested in secondary analyses of all previous SRHI applications, identified via systematic review, and in primary analyses of four raw datasets relating to energy-balance relevant behaviours (inactive travel, active travel, snacking, and alcohol consumption). A four-item automaticity subscale (the 'Self-Report Behavioural Automaticity Index'; 'SRBAI') was found to be reliable and sensitive to two hypothesised effects of habit on behaviour: a habit-behaviour correlation, and a moderating effect of habit on the intention-behaviour relationship. The SRBAI offers a parsimonious measure that adequately captures habitual behaviour patterns. The SRBAI may be of particular utility in predicting future behaviour and in studies tracking habit formation or disruption.

  19. "Moved by the spirit": does spirituality moderate the interrelationships between subjective well-being subscales?

    Science.gov (United States)

    Schuurmans-Stekhoven, James

    2010-07-01

    Despite the recent escalation of research into the spirituality and well-being link, past efforts have been plagued by methodological problems. However, the potential for measurement error within psychometric instruments remains largely unexplored. After reviewing theory and evidence suggesting spirituality might represent an affective misattribution, moderation modeling-with each subjective well-being (SWB) subscale as a dependent variable as predicted by the remaining SWB subscales-is utilized to test the assumption of scale invariance. These interrelationships were shown to vary in conjunction with spirituality; that is the analysis revealed significant spirituality x subscale interactions. Importantly, in all models the spirituality main effect was either nonsignificant or accounted for by other predictors. In combination, the findings suggest the interrelationship between the subscales rather than the level of SWB varies systematically with spirituality and casts considerable doubt on the previously reported "belief-as-benefit" effect.

  20. Psychometric properties of the existence subscale of the purpose in life questionnaire for Chinese adolescents in Hong Kong.

    Science.gov (United States)

    Law, Ben M F

    2012-01-01

    The current study aims to test the psychometric properties of the Existence Subscale of the Purpose in Life Questionnaire (EPIL) for early adolescence. The Purpose in Life Questionnaire (PIL), originally created by Craumbaugh and Maholick, is a 20-item scale measuring different dimensions of life purposes. The current study selected seven items representative of the existence dimension to form another scale, the EPIL. The analysis was based on 2842 early adolescents, ranging from 11 to 14 years old. Principal axis factoring found one factor, with 60% variance being explained. Cronbach's alpha for the EPIL was 0.89, which was high. The factor structure was stable across genders. Criterion-related validity was determined when the scale was used to differentiate volunteers and nonvolunteers. Construct validity was found when the scale was associated with life satisfaction. The results give support to the fact that the EPIL could be used alone to measure the psychological well-being of early adolescents and the appropriateness of the EPIL in adolescent research.

  1. The Correlation of SCL-90-R Anxiety, Depression, Somatization Subscale Scores with Chronic Low Back Pain.

    Science.gov (United States)

    Adilay, Utku; Guclu, Bulent; Goksel, Murat; Keskil, Semih

    2017-02-07

    The aim of this study was to investigate the correlation of the Symptom Checklist-90-R (SCL-90-R) anxiety, depression, and somatization subscale scores with chronic low back pain. In this study, 75 patients admitted with the complaint of chronic low back pain (patient group) and 75 healthy persons (control group) were evaluated. SCL-90-R anxiety, depression, and somatization subscale scores of patients having chronic low back pain and healthy persons were measured. The mean values were paired and using two tailed t test they were statistically evaluated. The difference between SCL-90-R anxiety subscale subscores of patients having choronic low back pain and healthy persons was statistically non significant (p 0.05).The difference betweenSCL-90-R depression subscale subscores of patients having chronic low back pain and healthy persons was statistically non significant (p 0.05). The difference between SCL-90-R somatization subscale subscores of patients having chronic low back pain and healthy persons was statistically significant (p 0.05). Our data show that SCL-90-R somatization subscale subscores were higher in patients with low back pain. The treatment of low back pain can be more successful when combined with the treatment of somatization.

  2. Modeling variability in item parameters in item response models

    NARCIS (Netherlands)

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

    2001-01-01

    In some areas of measurement item parameters should not be modeled as fixed but as random. Examples of such areas are: item sampling, computerized item generation, measurement with substantial estimation error in the item parameter estimates, and grouping of items under a common stimulus or in a

  3. Diabetes fatalism and its emotional distress subscale are independent predictors of glycemic control among Lebanese patients with type 2 diabetes.

    Science.gov (United States)

    Sukkarieh-Haraty, Ola; Egede, Leonard E; Abi Kharma, Joelle; Bassil, Maya

    2017-09-04

    Achieving and sustaining optimal glycemic control in type 2 diabetes (T2DM) is difficult because of socio-cultural and psychosocial factors including diabetes fatalism. Diabetes fatalism is 'a complex psychological cycle characterized by perceptions of despair, hopelessness, and powerlessness'. The purpose of this paper is to explore whether diabetes fatalism and other psychosocial and socio-cultural variables are correlates of glycemic control in Lebanese population with T2DM. A convenience sample of 280 adult participants with T2DM were recruited from a major hospital in greater Beirut-Lebanon area and from the community. Diabetes fatalism was assessed using the Arabic version of 12-item Diabetes Fatalism Scale. Multiple linear regression models were used to assess the relationship between HbA1c and psychosocial and socio-cultural characteristics including diabetes fatalism. Four models were run to examine the independent association between HbA1c and diabetes fatalism and to identify which of the 3 subscales (emotional distress, spiritual coping and perceived self-efficacy) were associated with HbA1c. The mean age of the participants was 58.24(SD = 13.48) and the majority were females (53.76%), while 32.73% of the sample had diabetes for more than 10 years. Fully adjusted multiple linear regression models showed that higher scores on diabetes fatalism and the emotional distress subscale (P = 0.018) were significantly associated with higher HbA1c values. In addition, having diabetes for more than 11 years (P = 0.05) and a higher number of diabetes complications (P fatalism as an independent predictor of glycemic control among Lebanese. Future studies should further investigate this construct to guide interventions that can address it for better diabetes outcomes.

  4. Spearman's hypothesis tested comparing Libyan secondary school children with various other groups of secondary school children on the items of the Standard Progressive Matrices

    NARCIS (Netherlands)

    te Nijenhuis, J.; Al-Shahomee, A.A.; van den Hoek, M.; Allik, J.; Grigoriev, A.; Dragt, J.

    2015-01-01

    Spearman's hypothesis tested at the level of items states that differences between groups on the items of an IQ test are a function of the g loadings of these items, such that there are small differences between groups on items with low g loadings and large differences between groups on items with

  5. Evaluation of psychometric properties and differential item functioning of 8-item Child Perceptions Questionnaires using item response theory.

    Science.gov (United States)

    Yau, David T W; Wong, May C M; Lam, K F; McGrath, Colman

    2015-08-19

    Four-factor structure of the two 8-item short forms of Child Perceptions Questionnaire CPQ11-14 (RSF:8 and ISF:8) has been confirmed. However, the sum scores are typically reported in practice as a proxy of Oral health-related Quality of Life (OHRQoL), which implied a unidimensional structure. This study first assessed the unidimensionality of 8-item short forms of CPQ11-14. Item response theory (IRT) was employed to offer an alternative and complementary approach of validation and to overcome the limitations of classical test theory assumptions. A random sample of 649 12-year-old school children in Hong Kong was analyzed. Unidimensionality of the scale was tested by confirmatory factor analysis (CFA), principle component analysis (PCA) and local dependency (LD) statistic. Graded response model was fitted to the data. Contribution of each item to the scale was assessed by item information function (IIF). Reliability of the scale was assessed by test information function (TIF). Differential item functioning (DIF) across gender was identified by Wald test and expected score functions. Both CPQ11-14 RSF:8 and ISF:8 did not deviate much from the unidimensionality assumption. Results from CFA indicated acceptable fit of the one-factor model. PCA indicated that the first principle component explained >30 % of the total variation with high factor loadings for both RSF:8 and ISF:8. Almost all LD statistic dependency. Flat and low IIFs were observed in the oral symptoms items suggesting little contribution of information to the scale and item removal caused little practical impact. Comparing the TIFs, RSF:8 showed slightly better information than ISF:8. In addition to oral symptoms items, the item "Concerned with what other people think" demonstrated a uniform DIF (p < 0.001). The expected score functions were not much different between boys and girls. Items related to oral symptoms were not informative to OHRQoL and deletion of these items is suggested. The impact of

  6. Evaluation of Buss-Perry aggression Questionnaire with item response theory (IRT

    Directory of Open Access Journals (Sweden)

    Dinić Bojana

    2012-01-01

    Full Text Available The aim of this research was to examine the psychometric properties of the Buss-Perry Aggression Questionnaire on Serbian sample, using the IRT model for graded responses. AQ contains four subscales: Physical aggression, Verbal aggression, Hostility and Anger. The sample included 1272 participants, both gender and age ranged from 18 to 68 years, with average age of 31.39 (SD = 12.63 years. Results of IRT analysis suggested that the subscales had greater information in the range of above-average scores, namely in participants with higher level of aggressiveness. The exception was Hostilisty subscale, because it was informative in the wider range of trait. On the other hand, this subscale contains two items which violate assumption of homogenity. Implications for measurement of aggressiveness are discussed.

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  8. 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.

  9. Effects of zinc supplementation on subscales of anorexia in children: A randomized controlled trial.

    Science.gov (United States)

    Khademian, Majid; Farhangpajouh, Neda; Shahsanaee, Armindokht; Bahreynian, Maryam; Mirshamsi, Mehran; Kelishadi, Roya

    2014-01-01

    This study aims to assess the effects of zinc supplementation on improving the appetite and its subscales in children. This study was conducted in 2013 in Isfahan, Iran. It had two phases. At the first step, after validation of the Child Eating Behaviour Questionaire (CEBQ), it was completed for 300 preschool children, who were randomly selected. The second phase was conducted as a randomized controlled trial. Eighty of these children were randomly selected, and were randomly assigned to two groups of equal number receiving zinc (10 mg/day) or placebo for 12 weeks. Overall 77 children completed the trial (39 in the case and 3 in the control group).The results showed that zinc supplement can improve calorie intake in children by affecting some CEBQ subscales like Emotional over Eating and Food Responsible. Zinc supplementation had positive impact in promoting the calorie intake and some subscales of anorexia.

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  11. The Prediction of Paranoid Behavior: Comparative Validities of Obvious vs. Subtle MMPI Paranoia (Pa) Items.

    Science.gov (United States)

    Hovanitz, Christine A.; And Others

    1983-01-01

    Investigated the relationship between the Minnesota Multiphasic Personality Inventory paranoia subtle, neutral, and obvious subscales and criteria presumed to reflect various paranoid characteristics in a sample of male college students (N=100). Results showed that both the obvious and subtle Pa Items predicted various criteria. (Author/JAC)

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

    NARCIS (Netherlands)

    Scott, Neil W.; Fayers, Peter M.; Aaronson, Neil K.; Bottomley, Andrew; de Graeff, Alexander; Groenvold, Mogens; Gundy, Chad; Koller, Michael; Petersen, Morten A.; Sprangers, Mirjam A. G.

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

  13. Item-level and scale-level factor structures of the MMPI-A.

    Science.gov (United States)

    Archer, R P; Belevich, J K; Elkins, D E

    1994-04-01

    The Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A) is a 478-item test that represents a substantial revision of the original form of the MMPI. This investigation sought to identify the item-level factor structure of the MMPI-A and also examined the scale-level factor structure of the 69 scales and subscales of this instrument. The study utilized the 1,620 normal adolescents (805 boys and 815 girls) of the normative sample for the MMPI-A. These adolescents ranged in age from 14 to 18, inclusive, with a mean age of 15.54 for boys and 15.60 for girls. A principal factor analysis of item-level responses resulted in extraction of 14 factors that were subjected to promax (oblique) rotation procedures. These 14 factors incorporated 81% of the total MMPI-A item pool and accounted for 44% of the total item-level response variance. For the scale-level analysis, 8 factors were selected for extraction and submitted to promax rotation procedures. These eight factors accounted for a total of 93.5% of the total variance in MMPI-A scale and subscale raw scores. Item-level results were discussed in terms of areas of congruence and dissimilarities from previously reported MMPI factor analyses in adolescent and adult samples, and scale-level factor results were presented in terms of clinical implications for the interpretation of MMPI-A scales and subscales.

  14. Validation of the 4DSQ somatization subscale in the occupational health care setting as a screener.

    Science.gov (United States)

    de Vroege, Lars; Emons, Wilco H M; Sijtsma, Klaas; Hoedeman, Rob; van der Feltz-Cornelis, Christina M

    2015-03-01

    Somatoform disorders (physical symptoms without medical explanation that cause dysfunction) are prevalent in the occupational health (OH) care setting and are associated with functional impairment and absenteeism. Availability of psychometric instruments aimed at assessing somatoform disorders is limited. In the OH setting, so far only the Patient-Health-Questionnaire 15 has been validated as screener for somatoform disorder, and has been shown to have moderate validity. The Four-Dimensional Symptom Questionnaire (4DSQ) is frequently used in the OH setting but the Somatization subscale is not validated yet. The aim of this study is to validate the 4DSQ Somatization subscale as screener for DSM-IV somatoform disorder in the OH setting by using the MINI interview as gold standard. Employees absent from work due to physical symptoms, for a period longer than 6 weeks and shorter than 2 years, were asked to participate in this study. They filled out the 4DSQ and underwent a MINI interview by telephone for DSM-IV classification. Specificity and sensitivity scores were calculated for all possible cut-off scores and a receiver operator curve was computed for the Somatization subscale. 95 % confidence intervals (95 % CIs) were calculated for sensitivity and specificity. The Somatization subscale of the 4DSQ has an optimal cut point of 9, with specificity and sensitivity equal to 64.3 % [95 % CI (53.6; 73.7 %)] and 60.9 % [95 % CI (40.8; 77.8 %)], respectively. Receiver operator curves showed an area under the curve equal to 0.61 [SE = 0.07; 95 % CI (0.48; 0.75)] for the Somatization subscale of the 4DSQ. The 4DSQ Somatization subscale is a questionnaire of moderate sensitivity and specificity.

  15. 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.

  16. Acquiring negative polarity items

    NARCIS (Netherlands)

    Lin, J.

    2015-01-01

    Negative Polarity Items (NPIs) are words or expressions that exhibit a restricted distribution to certain negative contexts only. For example, yet is an NPI and must appear in the scope of a negation: Mary has *(not) finished yet. The existence of NPIs such as yet gives rise to a learnability

  17. Investigating an Invariant Item Ordering for Polytomously Scored Items

    Science.gov (United States)

    Ligtvoet, Rudy; van der Ark, L. Andries; te Marvelde, Janneke M.; Sijtsma, Klaas

    2010-01-01

    This article discusses the concept of an invariant item ordering (IIO) for polytomously scored items and proposes methods for investigating an IIO in real test data. Method manifest IIO is proposed for assessing whether item response functions intersect. Coefficient H[superscript T] is defined for polytomously scored items. Given that an IIO…

  18. Psychometric analysis of the Ten-Item Perceived Stress Scale.

    Science.gov (United States)

    Taylor, John M

    2015-03-01

    Although the 10-item Perceived Stress Scale (PSS-10) is a popular measure, a review of the literature reveals 3 significant gaps: (a) There is some debate as to whether a 1- or a 2-factor model best describes the relationships among the PSS-10 items, (b) little information is available on the performance of the items on the scale, and (c) it is unclear whether PSS-10 scores are subject to gender bias. These gaps were addressed in this study using a sample of 1,236 adults from the National Survey of Midlife Development in the United States II. Based on self-identification, participants were 56.31% female, 77% White, 17.31% Black and/or African American, and the average age was 54.48 years (SD = 11.69). Findings from an ordinal confirmatory factor analysis suggested the relationships among the items are best described by an oblique 2-factor model. Item analysis using the graded response model provided no evidence of item misfit and indicated both subscales have a wide estimation range. Although t tests revealed a significant difference between the means of males and females on the Perceived Helplessness Subscale (t = 4.001, df = 1234, p < .001), measurement invariance tests suggest that PSS-10 scores may not be substantially affected by gender bias. Overall, the findings suggest that inferences made using PSS-10 scores are valid. However, this study calls into question inferences where the multidimensionality of the PSS-10 is ignored. 2015 APA, all rights reserved

  19. Less Is More: Using Static-2002R Subscales to Predict Violent and General Recidivism Among Sexual Offenders.

    Science.gov (United States)

    Babchishin, Kelly M; Hanson, R Karl; Blais, Julie

    2016-04-01

    Given that sexual offenders are more likely to reoffend with a nonsexual offense than a sexual offense, it is useful to have risk scales that predict general recidivism among sexual offenders. In the current study, we examined the extent to which two commonly used risk scales for sexual offenders (Static-99R and Static-2002R) predict violent and general recidivism, and whether it would be possible to improve predictive accuracy for these outcomes by revising their items. Based on an aggregated sample of 3,536 adult male sex offenders from Canada, the United States, and Europe (average age of 39 years), we found that a scale created from the Age at Release item and the General Criminality subscale of Static-2002R predicted nonsexual violent, any violent, and general recidivism significantly better than Static-99R or Static-2002R total scores. The convergent validity of this new scale (Brief Assessment of Recidivism Risk-2002R [BARR-2002R]) was examined in a new, independent data set of Canadian high-risk adult male sex offenders (N = 360) where it was found to be highly correlated with other risk assessment tools for general recidivism and the Psychopathy Checklist-Revised (PCL-R), as well as demonstrated similar discrimination and calibration as in the development sample. Instead of using total scores from the Static-99R or Static-2002R, we recommend that evaluators use the BARR-2002R for predicting violent and general recidivism among sex offenders, and for screening for the psychological dimension of antisocial orientation. © The Author(s) 2015.

  20. Chilean experimental version of the State-Trait Depression Questionnaire (ST-DEP: Trait sub-scale (T-DEP

    Directory of Open Access Journals (Sweden)

    Pablo Vera-Villarroel

    2008-01-01

    Full Text Available This instrumental study presents the first validity and reliability data for the Trait subscale (T-DEP of the Chilean experimental version of the State and Trait Depression Inventory (ST-DEP: Euthymia and Dysthymia. The data were obtained from a sample of 300 university students. The internal consistency values for the TDEP were high (.90. The test-retest values from eight weeks time interval (fifty six days were elevated (.78. A factorial analysis of the principal components revealed a principal factor for all of the constructed items in this experimental version of the TDEP. The last, promax rotation showed two clear main factors similar in size: negative affectivity (Dysthymia and positive affectivity (Euthymia. The convergent validity indexes for the Beck Depression Inventory and the Zung Self Rating Depression Scale, were also high, with indexes ranging from .64 to .71. The correlation between State- Trait Anxiety Inventory and the depression scales used in this study was high (between .63 and .78, once again indicating the usual overlapping between anxiety and depression seen in most depression inventories.

  1. Comparative Responsiveness of the PROMIS Pain Interference Short Forms, Brief Pain Inventory, PEG, and SF-36 Bodily Pain Subscale.

    Science.gov (United States)

    Kean, Jacob; Monahan, Patrick O; Kroenke, Kurt; Wu, Jingwei; Yu, Zhangsheng; Stump, Tim E; Krebs, Erin E

    2016-04-01

    To compare the sensitivity to change and the responsiveness to intervention of the PROMIS Pain Interference short forms, Brief Pain Inventory (BPI), 3-item PEG scale, and SF-36 Bodily Pain subscale in a sample of patients with persistent musculoskeletal pain of moderate severity. Standardized response means, standardized effect sizes, and receiver operating curve analyses were used to assess change between baseline and 3-month assessments in 250 participants who participated in a randomized clinical effectiveness trial of collaborative telecare management for moderate to severe and persistent musculoskeletal pain. The BPI, PEG, and SF-36 Bodily Pain measures were more sensitive to patient-reported global change than the PROMIS Pain Interference short forms, especially for the clinically improved group, for which the change detected by the PROMIS short forms was not statistically significant. The BPI was more responsive to the clinical intervention than the SF-36 Bodily Pain and PROMIS Pain Interference measures. Post hoc analyses exploring these findings did not suggest that differences in content or rating scale structure (number of response options or anchoring language) adequately explained the observed differences in the detection of change. In this clinical trial, the BPI and PEG measures were better able to detect change than the SF-36 Bodily Pain and PROMIS Pain Interference measures.

  2. 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…

  3. Comparison of Child Behavior Checklist subscales in screening for obsessive-compulsive disorder

    DEFF Research Database (Denmark)

    Andersen, Pia Aaron Skovby; Bilenberg, Niels

    2012-01-01

    Obsessive-compulsive disorder (OCD) is a prevalent psychiatric disorder in children and adolescents associated with significant functional impairment. Early and correct diagnosis is essential for an optimal treatment outcome. The purpose of this study was to determine which of four subscales...... derived from the Child Behavior Checklist best discriminates OCD patients from clinical and population-based controls....

  4. Student-constructed examination items.

    Science.gov (United States)

    Hoffman, K I; Solinas, J; Marshall, G J

    1978-01-01

    Student-written items were compared with teacher-written items on an objective examination given to first year medical students. While student scores were higher on the student-written items than on teacher-written items, there was a positive correlation between the scores. Student items did not differ from teacher items in the course, according to student ratings of emphasis. As a by-product of this study, correlations were found which suggest that student scores on an item often reflect the degree of teaching emphasis given the content area of the item rather than the inherent difficulty of the content. It is suggested that further research is needed to determine whether students learn through the process of writing examination items. Therefore, if the process proves to be educational, this study indicates that it will be feasible to incorporate the student-constructed items in examinations.

  5. 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.

  6. What factors make science test items especially difficult for students from minority groups?

    Directory of Open Access Journals (Sweden)

    Are Turmo

    2012-06-01

    Full Text Available Substantial gaps in science performance between majority and minority students are often found instandardized tests used in primary school. But at the item level, the gaps may vary significantly. Theaims of this study are: (1 to identify features of the test items in science (grade 5 and grade 8 students that can potentially explain group differences; and (2 to analyze what factors make test itemsespecially difficult for minority students. Explanatory variables such as reading load, item difficulty,item writing load, and use of the multiple-choice format are found to be major factors. The analysis reveals no empirical relationships between performance gap and either item subject domain, item test location, or the number of illustrations used in the item. Subtle issues regarding the design ofitems may influence the size of the performance gap at item level over and above the main explanatory variables. The gap can be reduced significantly by choosing “minority friendly” items.

  7. 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…

  8. Thermodynamic analysis and subscale modeling of space-based orbit transfer vehicle cryogenic propellant resupply

    Science.gov (United States)

    Defelice, David M.; Aydelott, John C.

    1987-01-01

    The resupply of the cryogenic propellants is an enabling technology for spacebased orbit transfer vehicles. As part of the NASA Lewis ongoing efforts in microgravity fluid management, thermodynamic analysis and subscale modeling techniques were developed to support an on-orbit test bed for cryogenic fluid management technologies. Analytical results have shown that subscale experimental modeling of liquid resupply can be used to validate analytical models when the appropriate target temperature is selected to relate the model to its prototype system. Further analyses were used to develop a thermodynamic model of the tank chilldown process which is required prior to the no-vent fill operation. These efforts were incorporated into two FORTRAN programs which were used to present preliminary analyticl results.

  9. The measurement of alexithymia in children and adolescents: Psychometric properties of the Alexithymia Questionnaire for Children and the twenty-item Toronto Alexithymia Scale in different non-clinical and clinical samples of children and adolescents.

    Science.gov (United States)

    Loas, Gwenolé; Braun, Stéphanie; Delhaye, Marie; Linkowski, Paul

    2017-01-01

    This study had two aims. Firstly, the psychometric properties of the 20-item Toronto Alexithymia Scale (TAS-20) and the Alexithymia Questionnaire for Children (AQC) that measure the three dimensions of alexithymia (DIF, difficulty identifying feelings; DDF, difficulty describing feelings; EOT, externally-oriented thinking) were explored in various samples of children, adolescents or young adults to detect the best factor-structure and to examine if the Externally-Oriented Thinking (EOT) factor must be deleted or not. Secondly, the capacity for adolescents to distinguish between alexithymia and depression was studied using factorial analyses of items of self-report of alexithymia and depression scales. Four groups were examined (80 healthy children, 105 adolescents with various psychiatric disorders, 333 healthy older adolescents and 505 young adults recruited from universities). The first two groups filled out the AQC and the latter two the TAS-20. Confirmatory factorial analyses (CFA) showed that the two-factor model (DIF, DDF) provided acceptable fits and had significant advantages over the three-factor model (DIF, DDF, EOT). Low alpha coefficients for the EOT subscale were reported (range from 0.18-0.61). Except for the children sample, exploratory factorial analyses (EFA) were performed on the items of the TAS-20 or AQC without the EOT items and the Beck depression inventory-II (BDI-II) or the Zung Self-Rating Depression Scale (SDS). The items of the AQC and BDI-II or items of the TAS-20 and SDS loaded on separate factors with only a minor overlap suggesting that adolescents were able to differentiate alexithymia and depression when self-assessments were used. Alexithymia can be reliably assessed in adolescents using the TAS-20 or AQC without the eight items rating the EOT dimension.

  10. Psychometric validation of the Hopkins Symptom Checklist (SCL-90) subscales for depression, anxiety, and interpersonal sensitivity

    DEFF Research Database (Denmark)

    Bech, P; Bille, Jim; Møller, Stine Bjerrum

    2014-01-01

    patients with various diagnoses, was tested. RESULTS: The PCA of the SCL-D16 and the SCL-A14 separated the core depression items from the arousal items on the SCL-D16 and the psychic anxiety items from the somatic anxiety items on the SCL-A14. According to the Mokken analyses, only the SCL-D6, the SCL-ASS8...... and the IPS5 were unidimensional. Interestingly, the same three scales displayed discriminant validity for depression, anxiety disorders and personality disorders, respectively. LIMITATIONS: The study is based on data from Denmark. This may limit the validity of the results. CONCLUSIONS: Three unidimensional...

  11. A new look at the psychometrics of the parenting scale through the lens of item response theory.

    Science.gov (United States)

    Lorber, Michael F; Xu, Shu; Slep, Amy M Smith; Bulling, Lisanne; O'Leary, Susan G

    2014-01-01

    The psychometrics of the Parenting Scale's Overreactivity and Laxness subscales were evaluated using item response theory (IRT) techniques. The IRT analyses were based on 2 community samples of cohabiting parents of 3- to 8-year-old children, combined to yield a total sample size of 852 families. The results supported the utility of the Overreactivity and Laxness subscales, particularly in discriminating among parents in the mid to upper reaches of each construct. The original versions of the Overreactivity and Laxness subscales were more reliable than alternative, shorter versions identified in replicated factor analyses from previously published research and in IRT analyses in the present research. Moreover, in several cases, the original versions of these subscales, in comparison with the shortened versions, exhibited greater 6-month stabilities and correlations with child externalizing behavior and couple relationship satisfaction. Reliability was greater for the Laxness than for the Overreactivity subscale. Item performance on each subscale was highly variable. Together, the present findings are generally supportive of the psychometrics of the Parenting Scale, particularly for clinical research and practice. They also suggest areas for further development.

  12. Fewer study participants needed to demonstrate superior antidepressant efficacy when using the Hamilton melancholia subscale (HAM-D6) as outcome measure

    DEFF Research Database (Denmark)

    Østergaard, Søren Dinesen; Bech, Per; Miskowiak, Kamilla Woznica

    2016-01-01

    Background In the development of new antidepressant treatments, the failed study has unfortunately become a prevalent problem. The number of failed studies could probably be reduced significantly by applying more informative outcome measures. Previous studies have indicated that the 6-item melanc...... questions addressed in this study.  Conclusions Both for ethical and financial reasons it is of interest to minimize the number of participants in clinical trials. Therefore, we suggest employing the HAM-D6 as outcome measure in clinical trials of depression.......Background In the development of new antidepressant treatments, the failed study has unfortunately become a prevalent problem. The number of failed studies could probably be reduced significantly by applying more informative outcome measures. Previous studies have indicated that the 6-item...... melancholia subscale (HAM-D6) of the 17-item Hamilton Depression Rating Scale (HAM-D17) may be more informative than other scales, due to its superior psychometric properties. In the present study we investigated whether the HAM-D6 had higher informativeness than the HAM-D17 based on data from a randomized...

  13. Measurement characteristics for two health-related quality of life measures in older adults: The SF-36 and the CDC Healthy Days items.

    Science.gov (United States)

    Barile, John P; Horner-Johnson, Willi; Krahn, Gloria; Zack, Matthew; Miranda, David; DeMichele, Kimberly; Ford, Derek; Thompson, William W

    2016-10-01

    The Short Form Health Survey (SF-36) and the Centers for Disease Control and Prevention (CDC) Healthy Days items are well known measures of health-related quality of life. The validity of the SF-36 for older adults and those with disabilities has been questioned. Assess the extent to which the SF-36 and the Centers for Disease Control and Prevention (CDC) Healthy Days items measure the same aspects of health; whether the SF-36 and the CDC unhealthy days items are invariant across gender, functional status, or the presence of chronic health conditions of older adults; and whether each of the SF-36's eight subscales is independently associated with the CDC Healthy Days items. We analyzed data from 66,269 adult Medicare advantage members age 65 and older. We used confirmatory factor analyses and regression modeling to test associations between the CDC Healthy Days items and subscales of the SF-36. The CDC Healthy Days items were associated with the SF-36 global measures of physical and mental health. The CDC physically unhealthy days item was associated with the SF-36 subscales for bodily pain, physical role limitations, and general health, while the CDC mentally unhealthy days item was associated with the SF-36 subscales for mental health, emotional role limitations, vitality and social functioning. The SF-36 physical functioning subscale was not independently associated with either of the CDC Healthy Days items. The CDC Healthy Days items measure similar domains as the SF-36 but appear to assess HRQOL without regard to limitations in functioning. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Item Overexposure in Computerized Classification Tests Using Sequential Item Selection

    Directory of Open Access Journals (Sweden)

    Alan Huebner

    2012-06-01

    Full Text Available Computerized classification tests (CCTs often use sequential item selection which administers items according to maximizing psychometric information at a cut point demarcating passing and failing scores. This paper illustrates why this method of item selection leads to the overexposure of a significant number of items, and the performances of three different methods for controlling maximum item exposure rates in CCTs are compared. Specifically, the Sympson-Hetter, restricted, and item eligibility methods are examined in two studies realistically simulating different types of CCTs and are evaluated based upon criteria including classification accuracy, the number of items exceeding the desired maximum exposure rate, and test overlap. The pros and cons of each method are discussed from a practical perspective.

  15. Comparative, validity and responsiveness of the HOOS-PS and KOOS-PS to the WOMAC physical function subscale in total joint replacement for osteoarthritis

    DEFF Research Database (Denmark)

    Davis, A M; Perruccio, A V; Canizares, M

    2009-01-01

    OBJECTIVE: To evaluate the internal consistency of the Hip disability and Osteoarthritis Outcome Score-Physical Function Short-form (HOOS-PS) and the Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form (KOOS-PS) in total hip replacement (THR) and total knee (TKR) replacement....... Construct validity and responsiveness were compared to the Western Ontario McMaster Universities' Osteoarthritis Index (WOMAC) Likert 3.0 physical function (PF) subscale and the PF excluding the items in the short measures (PF-exclusions). METHODS: Participants completed the full HOOS or KOOS, measures...... of fatigue, anxiety, depression and the Chronic Pain Grade (CPG) pre-surgery and the HOOS or KOOS 6 months post-surgery. Internal consistency for the HOOS-PS and KOOS-PS was calculated using Cronbach's alpha. For construct validity, it was hypothesized that correlations between the HOOS-PS or KOOS-PS and PF...

  16. Validity of the definite and semidefinite questionnaire version of the Hamilton Depression Scale, the Hamilton subscale and the Melancholia Scale. Part I

    DEFF Research Database (Denmark)

    Hansen, Jesper Bent; Bech, Per

    2011-01-01

    , and their corresponding definite versions of the self-rating questionnaires DMQ and DHAM6 were accepted by the Rasch analysis, and only these four valid scales discriminated significantly between the effect of citalopram and placebo treatment. Our results are limited to patients with moderate depression. Two new self......-reporting versions (definitely and semidefinitely anchored) corresponding to the Hamilton Depression Scale (HAMD), the Hamilton Subscale (HAM6), and the Bech-Rafaelsen Melancholia Scale (MES) were compared to each other and the clinician-rated version. The unidimensional property of the sum score in each scale...... was tested by the item-response theory model ad modum Rasch. The scales were also tested for their sensitivity to discriminate between placebo and citalopram therapy. The sum scores and the sum score variances of the definite self-rating versions did not differ significantly from the sum scores...

  17. Evidence That the Clinical Impairment Assessment (CIA) Subscales Should Not Be Scored: Bifactor Modelling, Reliability, and Validity in Clinical and Community Samples.

    Science.gov (United States)

    Raykos, Bronwyn; Erceg-Hurn, David; McEvoy, Peter; Byrne, Susan M

    2017-09-01

    The Clinical Impairment Assessment (CIA 3.0) is the most widely used instrument assessing psychosocial impairment secondary to eating disorder symptoms. However, there is conflicting advice regarding the dimensionality and optimal method of scoring the CIA. We sought to resolve this confusion by conducting a comprehensive factor analytic study of the CIA in a community sample ( N = 301) and clinical sample comprising patients with a diagnosed eating disorder ( N = 209). Convergent and discriminant validity were also assessed. The CIA and measures of eating disorder symptoms were administered to both samples. Factor analyses indicated there is a general impairment factor underlying all items on the CIA that is reliably measured by the CIA Global score. CIA Global demonstrated good convergent and discriminant validity. CIA Global is a reliable and valid measure of psychosocial impairment secondary to eating disorder symptoms; however, subscale scores should not be computed.

  18. Adverse learning strategy: the Adelaide Diagnostic Learning Inventory and its subscale replicability in a medical student population.

    Science.gov (United States)

    Welch, G; Pearce, K; Lewis, M; Mellsop, G

    1990-03-01

    The Adelaide Diagnostic Learning Inventory (ADLIMS) is a measure of learning styles and learning pathologies that was designed to investigate the impact of traditional approaches to learning versus problem-based learning and to identify students whose approach to learning tasks predicted poor academic performance. In this study, some important psychometric properties of the ADLIMS were examined, including its factor structure. In this study, factor replicability across samples was argued to provide a more robust and psychologically meaningful factor solution than that which can be obtained using traditional mathematical criteria. The results of the factor analysis did not confirm the presence of the four factor solution earlier reported for the ADLIMS, but did identify three clear factors that had very high replicability. An inspection of the items comprising these three factors showed that factor 1 tapped subjective distress related to poor study habits, lack of motivation to study, and distraction from social activities. Factor 2 tapped distress arising from high achievement expectations that were hampered by superficial or disorganized study habits that did not enable the student to grasp the relationships between concepts and ideas. Factor 3 tapped positive feelings and a sense of satisfaction associated with a problem-based approach to the learning of new study material. Although the internal reliability of the ADLIMS subscales met the requirements of a measure to be used in general research such as in the investigation of correlates among groups of medical students, they did not meet the higher requirements of a measure to be used to identify or predict individuals with pathological learning styles.

  19. Domain-General and Domain-Specific Creative-Thinking Tests: Effects of Gender and Item Content on Test Performance

    Science.gov (United States)

    Hong, Eunsook; Peng, Yun; O'Neil, Harold F., Jr.; Wu, Junbin

    2013-01-01

    The study examined the effects of gender and item content of domain-general and domain-specific creative-thinking tests on four subscale scores of creative-thinking (fluency, flexibility, originality, and elaboration). Chinese tenth-grade students (234 males and 244 females) participated in the study. Domain-general creative thinking was measured…

  20. A study of the dimensionality and measurement precision of the SCL-90-R using item response theory

    NARCIS (Netherlands)

    Paap, Muirne C S; Meijer, Rob R; Van Bebber, Jan; Pedersen, Geir; Karterud, Sigmund; Hellem, Frøydis M; Haraldsen, Ira R.

    We used item response theory (IRT) to (a) investigate the dimensionality of the Symptom Checklist-90-Revised (SCL-90-R) in a severely disturbed patient group, (b) improve the subscales in a meaningful way and (c) investigate the measurement precision of the improved scales. The total sample

  1. Analysis of Item-Level Bias in the Bayley-III Language Subscales: The Validity and Utility of Standardized Language Assessment in a Multilingual Setting

    Science.gov (United States)

    Goh, Shaun K. Y.; Tham, Elaine K. H.; Magiati, Iliana; Sim, Litwee; Sanmugam, Shamini; Qiu, Anqi; Daniel, Mary L.; Broekman, Birit F. P.; Rifkin-Graboi, Anne

    2017-01-01

    Purpose: The purpose of this study was to improve standardized language assessments among bilingual toddlers by investigating and removing the effects of bias due to unfamiliarity with cultural norms or a distributed language system. Method: The Expressive and Receptive Bayley-III language scales were adapted for use in a multilingual country…

  2. Using data from Multidimensional Pain Inventory subscales to assess functioning in pain rehabilitation

    DEFF Research Database (Denmark)

    Harlacher, Uwe; Persson, Ann L; Rivano-Fischer, Marcelo

    2011-01-01

    The aim of this study was to examine whether Multidimensional Pain Inventory (MPI) subscale score changes can be used for monitoring interdisciplinary cognitive behavioural pain rehabilitation programmes, using the Psychological General Well-Being (PGWB) index as an independent variable...... of rehabilitation outcome. Data from 434 consecutively referred patients disabled by chronic pain were analysed. The intervention was a 4-week interdisciplinary pain rehabilitation group programme (5 h/day), based on biopsychosocial and cognitive behavioural principles. Mean PGWB total scores improved after...... rehabilitation (P...

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

    Directory of Open Access Journals (Sweden)

    Gideon P. De Bruin

    2004-10-01

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

  4. Neurotic tendencies among chronic pain patients: an MMPI item analysis.

    Science.gov (United States)

    Watson, D

    1982-01-01

    Previous research has shown chronic pain patients to have elevated scores on the Hypochondriasis (Hs), Depression (D), and Hysteria (Hy) scales of the MMPI. While high scores on these scales are generally considered to reflect neurotic symptomatology and emotional disturbance, their interpretation is more ambiguous within this patient population. Item-level and subscale analyses of these scales and the K scale (a measure of defensiveness) were performed in order to clarify the meaning of these elevated scores. In these analyses a pain group's endorsement of each item was compared with the responses of two control groups, one a general medical patient sample, the other consisting of first year college students. Items showing group endorsement differences of 10% or greater were interpreted as providing significant information about the pain sample. Analysis of the Hs items indicated that a significant portion of the pain group exhibited the vague and diffuse somatic complaining characteristic of hypochondriasis. While the D scale results revealed a considerable amount of depressive symptomatology (such as sleep disturbance, poor self-esteem, apathy, and feelings of unhappiness, anxiety, and dissatisfaction), they did not support the notion that pain patients have the personality characteristics associated with severe depression. Analyses of the Hy and K scales indicated that the pain patients were no more defensive than were either of the control groups, and that their responses did not conform to the classic hysterical pattern.

  5. Numerical Simulations of Subscale Wind Turbine Rotor Inboard Airfoils at Low Reynolds Number

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, Myra L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Thermal/ Fluid Sciences & Engineering Dept.; Maniaci, David Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Wind Energy Technologies Dept.; Resor, Brian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Wind Energy Technologies Dept.

    2015-04-01

    New blade designs are planned to support future research campaigns at the SWiFT facility in Lubbock, Texas. The sub-scale blades will reproduce specific aerodynamic characteristics of utility-scale rotors. Reynolds numbers for megawatt-, utility-scale rotors are generally above 2-8 million. The thickness of inboard airfoils for these large rotors are typically as high as 35-40%. The thickness and the proximity to three-dimensional flow of these airfoils present design and analysis challenges, even at the full scale. However, more than a decade of experience with the airfoils in numerical simulation, in the wind tunnel, and in the field has generated confidence in their performance. Reynolds number regimes for the sub-scale rotor are significantly lower for the inboard blade, ranging from 0.7 to 1 million. Performance of the thick airfoils in this regime is uncertain because of the lack of wind tunnel data and the inherent challenge associated with numerical simulations. This report documents efforts to determine the most capable analysis tools to support these simulations in an effort to improve understanding of the aerodynamic properties of thick airfoils in this Reynolds number regime. Numerical results from various codes of four airfoils are verified against previously published wind tunnel results where data at those Reynolds numbers are available. Results are then computed for other Reynolds numbers of interest.

  6. Practical Application of a Subscale Transport Aircraft for Flight Research in Control Upset and Failure Conditions

    Science.gov (United States)

    Cunningham, Kevin; Foster, John V.; Morelli, Eugene A.; Murch, Austin M.

    2008-01-01

    Over the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health monitoring, and reconfigurable control systems focused on flight regimes beyond the normal flight envelope. In recent years, there has been an increased emphasis on adaptive control technologies for recovery from control upsets or failures including damage scenarios. As part of these efforts, NASA has developed the Airborne Subscale Transport Aircraft Research (AirSTAR) flight facility to allow flight research and validation, and system testing for flight regimes that are considered too risky for full-scale manned transport airplane testing. The AirSTAR facility utilizes dynamically-scaled vehicles that enable the application of subscale flight test results to full scale vehicles. This paper describes the modeling and simulation approach used for AirSTAR vehicles that supports the goals of efficient, low-cost and safe flight research in abnormal flight conditions. Modeling of aerodynamics, controls, and propulsion will be discussed as well as the application of simulation to flight control system development, test planning, risk mitigation, and flight research.

  7. The use of Spielberger's State-Trait Personality Inventory (trait anxiety subscale) with naval subaquatic specialists.

    Science.gov (United States)

    Van Wijk, Charles H

    2014-12-01

    Panic behavior poses a particular threat to the health and safety of subaquatic occupational specialists. Trait anxiety has previously been identified as a marker of panic behavior under water, and Spielberger's State-Trait Personality Inventory (trait anxiety subscale) has been previously used to measure trait anxiety among subaquatic specialists. Using archived data, the trait anxiety scores of subaquatic specialists were analyzed to meet 3 objectives: 1stly - to develop a trait anxiety profile of subaquatic specialists; 2ndly - to investigate the predictive value of trait anxiety measures upon entering an occupational field; and 3rdly - to establish the reliability of these scores over time. Archival trait-anxiety data from 322 subjects were analyzed statistically. Analysis of the available scores revealed a highly homogenous as well as a very low trait anxiety profile for the investigated occupational group. Additionally, low trait anxiety was somewhat associated with success during specialist training: fewer candidates with high trait anxiety scores completed their qualification. Moreover, measurement of trait anxiety was stable over time, which suggests that when scores for this occupational group are screened, deviations from previous scores could signify a potential need for referral to an intervention from health professionals. Using the trait anxiety subscale as part of occupational health surveillance of subaquatic specialists could support prevention of accidents by identifying high-risk candidates during their annual health assessments, and referral for timeous intervention.

  8. Topographic effect of Sub-scale Mountains around the main Tibetan Plateau on Asian climate

    Science.gov (United States)

    Sha, Yingying; Shi, Zhengguo

    2017-04-01

    As one of the most important tectonic events in Cenozoic, the uplift of the Tibetan Plateau (TP) is considered to have profound influences on the evolution of Asian climate.However, the potential influence from the sub-scale mountains around the main TP is largely neglected. In actual, these sub-scale mountains may affect some climate systems, which facilitates from their sensitive locations. Taking the Mongolian Plateau (MP) and Yunnan-Guizhou Plateau (YGP, SW China) as examples, they are located at the core paths of mid-latitude winter westerly and Indian summer southwesterly monsoon, respectively, and seem to significantly block the eastward propagation of these systems from modern climatological data. In this study, general circulation model experiments with and without mountains are employed to evaluate the topographic effect of MP and YGP on the Asian climate. The results show that, the MP, despite its smaller size, exerts a great influence on the strengthened winter climate over East Asia, including the East Asian trough, the subtropical westerly jet and the winter monsoon. The YGP, however, plays an opposite role in the Indian monsoon change, compared to the main TP. It weakens the Indian summer monsoon circulation and associated precipitation. Thus, the response of Asian climate to the mountain uplift depends closely on the actual distributions of topography rather than a simplified bulk of main TP.

  9. WOMAC-pf as a measure of physical function in patients with Parkinson's disease and late-onset sequels of poliomyelitis: unidimensionality and item behaviour.

    Science.gov (United States)

    Steultjens, Martijn P M; Stolwijk-Swüste, Janneke; Roorda, Leo D; Dallmeijer, Annet J; van Dijk, Gabriella M; Post, Bart; Dekker, Joost

    2012-01-01

    To assess psychometric properties of the Western Ontario and MacMasters Universities Osteoarthritis Index (WOMAC)-pf, an osteoarthritis (OA)-specific questionnaire used to establish the level of physical functioning in patients with late-onset sequels of poliomyelitis (LOSP) and Parkinson's disease (PD). Unidimensionality (using principal component analyses [PCA] and Rasch analyses) was separately established for three diagnostic groups: OA (n = 288), LOSP (n = 168) and PD (n = 200). Additionally, differential item functioning (DIF) among the three diagnostic groups was assessed using ordinal regression (Polytomous Universal Model) analyses. Baseline data were used from an ongoing cohort study of these three patient populations. Unidimensionality was adequate, with all items loading on the first principal component. The Rasch analyses revealed that item fit was generally good. Uniform and non-uniform DIF were found to be present among the three diagnostic groups in three and one of the 17 physical functioning subscale (WOMAC-pf) items, respectively. The WOMAC-pf is a unidimensional measure of physical functioning in patients with LOSP and PD, in addition to its established use in OA. [ • Disability in physical functioning related to mobility(walking, stair climbing, etc.) is a common feature of many chronic diseases, including osteoarthritis, late-onset sequels of poliomyelitis and Parkinson's disease.• In this study, the Western Ontario and MacMasters Universities Osteoarthritis Index-pf was shown to bea useful and adequate tool to assess physical functioning in these patient groups.• The study highlighted that, despite differences in diagnosis,history and course of the disease, patients with different conditions experience similar disabilities in their physical functioning.

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

    African Journals Online (AJOL)

    The results showed a significant difference between the difficulty levels of test items in WAEC and NECO mathematics objective test instruments, with NECO having more difficulty level in their instruments, as reflected in the item characteristic curves. Thus, the NECO examination mathematics objective test was more difficult ...

  11. A mathematical theory of ability measure based on partial credit item responses.

    Science.gov (United States)

    Kong, Nan L

    2015-01-01

    This paper defines a measure of examinees' abilities using additivity, the fundamental property of a measure, based on the partially-credited item responses. The fundamental properties of this newly-defined ability measure are demonstrated using mathematical proofs. This paper also shows that interactive ability and conditional ability are measurable with additivity. Finally, the paper looks at the ability measures associated with subscales and their decompositions.

  12. Development of an instrument to measure staff-reported resident-to-resident elder mistreatment (R-REM) using item response theory and other latent variable models.

    Science.gov (United States)

    Teresi, Jeanne A; Ocepek-Welikson, Katja; Ramirez, Mildred; Eimicke, Joseph P; Silver, Stephanie; Van Haitsma, Kimberly; Lachs, Mark S; Pillemer, Karl A

    2014-06-01

    Although numerous studies have measured behaviors among individuals in congregate settings, few have focused on resident-to-resident elder mistreatment (R-REM). To our knowledge, there is no psychometrically developed measure of R-REM extant. The quantitative development of a measure of staff-reported R-REM is described. The design was a prevalent cohort study of residents of 5 long-term care facilities. The primary certified nursing assistant was interviewed about R-REM. Advanced measurement methods were used to develop a measure of R-REM. The loadings on the general factor for the final 11-item scale were greater than those on the group factor except for the item "other physical behavior" (0.63 vs. 0.74), suggesting essential unidimensionality. Although the bifactor model fit was slightly better than that of the unidimensional model, the difference was trivial (bifactor comparative fit index [CFI] = 0.997, root mean square error of approximation [RMSEA] = 0.013, unidimensional CFI = 0.979, and RMSEA = 0.030). However, modest support was provided for use of verbal and physical subscales. The explained common variance statistics were 0.76 for the bifactor model compared with 0.63 for the unidimensional model. The development of this R-REM measure will help to advance the measurement and ultimately evaluation of interventions associated with this important and under recognized problem facing residents in long-term care settings.

  13. Testing whether patients with diabetes and healthy people perceive the meaning of the items in the Persian version of the SF-36 questionnaire similarly: a differential item functioning analysis.

    Science.gov (United States)

    Bagheri, Zahra; Jafari, Peyman; Mahmoodi, Marzieh; Dabbaghmanesh, Mohammad Hossein

    2017-04-01

    It has been rarely studied whether observed disparity in health-related quality-of-life (HRQoL) scores between patients with diabetes and healthy individuals is due to differential item functioning (DIF) or a true difference in the underlying construct. This study aimed to examine DIF in the SF-36 questionnaire and its effect on comparing HRQoL scores between patients with diabetes and healthy people. The sample consisted of 230 patients with type 2 diabetes and 642 healthy individuals who filled out the Persian version of the SF-36 questionnaire. To detect DIF across patients with diabetes and healthy individuals, multiple-group multiple-indicator multiple-causes model was used. In addition, item calibration strategy was used to determine whether the effect of item-level DIF was transferred to the scale level. Nine out of thirty-six (25 %) items were detected as DIF, of which one item (11 %) was flagged as uniform and eight items (89 %) as non-uniform DIF. Most of the DIF items were detected in the mental health component which includes vitality, perceived mental health and social functioning subscales rather than in physical health component. Moreover, nonsignificant latent mean differences for general health perception and social functioning subscales became significant after DIF calibration. The findings of the present study show that patients with diabetes and healthy individuals perceived some items in the SF-36 questionnaire differently. More importantly, in some subscales, the effect of item-level DIF was transferred to the scale level. Consequently, considerable caution should be taken in comparing HRQoL scores between patients with diabetes and healthy individuals.

  14. Bundle pricing with comparable items

    NARCIS (Netherlands)

    Grigoriev, Alexander; van Loon, Joyce; Sviridenko, Maxim; Uetz, Marc Jochen; Vredeveld, Tjark; Arge, L.; Hoffmann, M.; Welzl, E.

    2007-01-01

    We consider a revenue maximization problem where we are selling a set of items, each available in a certain quantity, to a set of bidders. Each bidder is interested in one or several bundles of items. We assume the bidders’ valuations for each of these bundles to be known. Whenever bundle prices are

  15. Change of International Restless Legs Syndrome Study Group Rating Scale subscales with treatment and placebo: a pilot study

    Directory of Open Access Journals (Sweden)

    Mitchell UH

    2014-02-01

    Full Text Available Ulrike H Mitchell,1 Sterling C Hilton2 1Brigham Young University, Department of Exercise Sciences, 2Department of Educational Leadership and Foundations, Provo, UT, USA Background: In 2003, the 10-question International Restless Legs Syndrome Study Group Rating Scale (IRLS was developed as a means of assessing the severity of restless legs syndrome. Two subscales were identified: symptom severity (SS 1 and symptom impact (SS 2. Only one study has investigated the subscales' responsiveness to a 12-week treatment with ropinirole. This current study was undertaken to assess the impact of a 4-week, non-pharmaceutical treatment on the two subscales and to explore whether or not both subscales were impacted by the observed placebo effect. Methods: The pooled data from questionnaires of 58 patients (41 from both treatment groups and 17 from the sham treatment control group, who participated in two clinical studies, were reviewed. Their change in score over a 4-week trial was computed. The average change in both subscales in both groups was computed and t-tests were performed. Results: In the treatment group, the average scores of both subscales changed significantly from baseline to week 4 (P<0.005 for both. Compared to the control, SS 1 changed (P<0.001, but not SS 2 (P=0.18. In the sham treatment group, the scores for SS 1 changed significantly (P=0.002, but not for SS 2 (P=0.2. Conclusion: This study corroborated findings from an earlier study in which both subscales changed with a 12-week drug treatment. It also showed that the observed placebo effect is attributed to a small but significant change in symptom severity, but not symptom impact. Keywords: restless legs syndrome, RLS severity scale, IRLS subscales, symptom impact, symptom severity

  16. 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.

  17. 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

  18. A Mixed Effects Randomized Item Response Model

    Science.gov (United States)

    Fox, J.-P.; Wyrick, Cheryl

    2008-01-01

    The randomized response technique ensures that individual item responses, denoted as true item responses, are randomized before observing them and so-called randomized item responses are observed. A relationship is specified between randomized item response data and true item response data. True item response data are modeled with a (non)linear…

  19. Stability of memories of parental rearing among psychiatric inpatients: a replication based on EMBU subscales.

    Science.gov (United States)

    Richter, J; Eisemann, M

    2001-01-01

    With regard to information about parental rearing, retrospective data are exclusively available among adults. These data are vulnerable due to various biases. This study was performed in order to replicate the findings of overall stability of three perceived parental rearing factors of the EMBU (Swedish acronym for 'own memories of childhood upbringing') based on 14 rather detailed subscales. A consecutive sample of 220 depressive inpatients were investigated on admission and at discharge by means of the EMBU, the Beck Depression Inventory and the Dysfunctional Attitude Scale. Perceived parental rearing scores showed high stability despite clinically significant changes in the severity of depression, except for 'tolerance', 'guilt engendering', 'performance orientation' and 'shaming' parenting with probable gender-specific effects which were found to covary with dysfunctional attitudes. Recall of parenting should be taken as a subjective truth when it is assessed by standardised behaviour-oriented questionnaires like the EMBU. Copyright 2002 S. Karger AG, Basel

  20. Anxiety Sensitivity Index (ASI-3) subscales predict unique variance in anxiety and depressive symptoms.

    Science.gov (United States)

    Olthuis, Janine V; Watt, Margo C; Stewart, Sherry H

    2014-03-01

    Anxiety sensitivity (AS) has been implicated in the development and maintenance of a range of mental health problems. The development of the Anxiety Sensitivity Index - 3, a psychometrically sound index of AS, has provided the opportunity to better understand how the lower-order factors of AS - physical, psychological, and social concerns - are associated with unique forms of psychopathology. The present study investigated these associations among 85 treatment-seeking adults with high AS. Participants completed measures of AS, anxiety, and depression. Multiple regression analyses controlling for other emotional disorder symptoms revealed unique associations between AS subscales and certain types of psychopathology. Only physical concerns predicted unique variance in panic, only cognitive concerns predicted unique variance in depressive symptoms, and social anxiety was predicted by only social concerns. Findings emphasize the importance of considering the multidimensional nature of AS in understanding its role in anxiety and depression and their treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2015-01-01

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

  2. Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

    KAUST Repository

    Gasda, S. E.

    2009-04-23

    Large-scale implementation of geological CO2 sequestration requires quantification of risk and leakage potential. One potentially important leakage pathway for the injected CO2 involves existing oil and gas wells. Wells are particularly important in North America, where more than a century of drilling has created millions of oil and gas wells. Models of CO 2 injection and leakage will involve large uncertainties in parameters associated with wells, and therefore a probabilistic framework is required. These models must be able to capture both the large-scale CO 2 plume associated with the injection and the small-scale leakage problem associated with localized flow along wells. Within a typical simulation domain, many hundreds of wells may exist. One effective modeling strategy combines both numerical and analytical models with a specific set of simplifying assumptions to produce an efficient numerical-analytical hybrid model. The model solves a set of governing equations derived by vertical averaging with assumptions of a macroscopic sharp interface and vertical equilibrium. These equations are solved numerically on a relatively coarse grid, with an analytical model embedded to solve for wellbore flow occurring at the sub-gridblock scale. This vertical equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid refinement for sub-scale features. Through a series of benchmark problems, we show that VESA compares well with traditional numerical simulations and to a semi-analytical model which applies to appropriately simple systems. We believe that the VESA model provides the necessary accuracy and efficiency for applications of risk analysis in many CO2 sequestration problems. © 2009 Springer Science+Business Media B.V.

  3. Is a single-item visual analogue scale as valid, reliable and responsive as multi-item scales in measuring quality of life?

    Science.gov (United States)

    de Boer, A G E M; van Lanschot, J J B; Stalmeier, P F M; van Sandick, J W; Hulscher, J B F; de Haes, J C J M; Sprangers, M A G

    2004-03-01

    To compare the validity, reliability and responsiveness of a single, global quality of life question to multi-item scales. Data were obtained from 83 consecutive patients with oesophageal adenocarcinoma undergoing either transhiatal or transthoracic oesophagectomy. Quality of life was measured at baseline, 5 weeks, 3 and 12 months post-operatively with a single-item Visual Analogue Scale (VAS) ranging from 0 to 100, the multi-item Medical Outcomes Study Short Form-20 (MOS SF-20) and Rotterdam Symptom Check-List (RSCL). Convergent and discriminant validity, test-retest reliability and both distribution-based and anchor-based responsiveness were evaluated. At baseline and at 5 weeks, the VAS showed high correlations with the MOS SF-20 health perceptions scale (r = 0.70 and 0.72) and moderate to high correlations with all other subscales of the MOS SF-20 and RSCL (r = 0.29-0.70). The test-retest reliability intra-class correlation for the VAS was 0.87. At 5 weeks post-operatively, the distribution-based responsiveness was moderate for the VAS (standardised response mean: -0.47; effect size: -0.56), high for the physical subscales of the MOS SF-20 and RSCL (-1.08 to -1.51) and low for the psychological subscales (0.11 to -0.25). Five weeks post-operatively, anchor-based responsiveness was highest for the VAS (r = 0.54). The VAS is an instrument with good validity, excellent reliability, moderate distribution-based responsiveness and good anchor-based responsiveness compared to multi-item questionnaires. Its use is recommended in clinical trials to assess global quality of life.

  4. A Replication of the MMPI-A PSY-5 Scales and Development of Facet Subscales

    Science.gov (United States)

    Bolinskey, P. Kevin; Arnau, Randolph C.; Archer, Robert P.; Handel, Richard W.

    2004-01-01

    McNulty, Harkness, Ben-Porath and Williams recently developed Personality Psychopathology Five (PSY-5) scales for the Minnesota Multiphasic Personality Inventory A (MMPI-A). This study examined these new scales in a sample of 545 adolescents receiving inpatient psychiatric treatment. Item-level principal components analyses were employed to…

  5. Counting Frequencies from Zotero Items

    Directory of Open Access Journals (Sweden)

    Spencer Roberts

    2013-04-01

    Full Text Available In Counting Frequencies you learned how to count the frequency of specific words in a list using python. In this lesson, we will expand on that topic by showing you how to get information from Zotero HTML items, save the content from those items, and count the frequencies of words. It may be beneficial to look over the previous lesson before we begin.

  6. Maximizing measurement efficiency of behavior rating scales using Item Response Theory: An example with the Social Skills Improvement System - Teacher Rating Scale.

    Science.gov (United States)

    Anthony, Christopher J; DiPerna, James C; Lei, Pui-Wa

    2016-04-01

    Measurement efficiency is an important consideration when developing behavior rating scales for use in research and practice. Although most published scales have been developed within a Classical Test Theory (CTT) framework, Item Response Theory (IRT) offers several advantages for developing scales that maximize measurement efficiency. The current study provides an example of using IRT to maximize rating scale efficiency with the Social Skills Improvement System - Teacher Rating Scale (SSIS - TRS), a measure of student social skills frequently used in practice and research. Based on IRT analyses, 27 items from the Social Skills subscales and 14 items from the Problem Behavior subscales of the SSIS - TRS were identified as maximally efficient. In addition to maintaining similar content coverage to the published version, these sets of maximally efficient items demonstrated similar psychometric properties to the published SSIS - TRS. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  7. An Item Gains and Losses Analysis of False Memories Suggests Critical Items Receive More Item-Specific Processing than List Items

    Science.gov (United States)

    Burns, Daniel J.; Martens, Nicholas J.; Bertoni, Alicia A.; Sweeney, Emily J.; Lividini, Michelle D.

    2006-01-01

    In a repeated testing paradigm, list items receiving item-specific processing are more likely to be recovered across successive tests (item gains), whereas items receiving relational processing are likely to be forgotten progressively less on successive tests. Moreover, analysis of cumulative-recall curves has shown that item-specific processing…

  8. A scaling method for combustion stability rating of coaxial gas liquid injectors in a subscale chamber

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chae Hoon; Kim, Young Jun [Sejong Univ., Seoul (Korea, Republic of); Kim, Young Mog [Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Pikalov, Valery P. [Research Institute of Chemical Machine Building, Sergiev Posad (Russian Federation)

    2012-11-15

    A scaling method to examine combustion stability characteristics of a coaxial injector is devised based on the acoustics and combustion dynamics in a chamber. The method is required for a subscale test of stability rating with a model chamber, which is cost effective compared with an actual full scale test. First, scaling and similarity rules are considered for stability rating and thereby, three conditions of acoustic, hydrodynamic, and flame condition similarities are proposed. That is, for acoustic similarity, the natural or resonant frequencies in the actual chamber should be maintained in the model chamber. And, two parameters of density ratio and velocity ratio are derived for the requirement of hydrodynamic and flame condition similarities between the actual and the model conditions. Next, one example of an actual combustion chamber with high performance is selected and the proposed scaling method is applied to the chamber for understanding of the method. The design operating condition for a model test is presented by mass flow rates of propellants. Stability boundaries can be identified on the coordinate plane of chamber pressure and mixture ratio of fuel and oxidizer by applying the scaling method.

  9. Static Aeroelastic Scaling and Analysis of a Sub-Scale Flexible Wing Wind Tunnel Model

    Science.gov (United States)

    Ting, Eric; Lebofsky, Sonia; Nguyen, Nhan; Trinh, Khanh

    2014-01-01

    This paper presents an approach to the development of a scaled wind tunnel model for static aeroelastic similarity with a full-scale wing model. The full-scale aircraft model is based on the NASA Generic Transport Model (GTM) with flexible wing structures referred to as the Elastically Shaped Aircraft Concept (ESAC). The baseline stiffness of the ESAC wing represents a conventionally stiff wing model. Static aeroelastic scaling is conducted on the stiff wing configuration to develop the wind tunnel model, but additional tailoring is also conducted such that the wind tunnel model achieves a 10% wing tip deflection at the wind tunnel test condition. An aeroelastic scaling procedure and analysis is conducted, and a sub-scale flexible wind tunnel model based on the full-scale's undeformed jig-shape is developed. Optimization of the flexible wind tunnel model's undeflected twist along the span, or pre-twist or wash-out, is then conducted for the design test condition. The resulting wind tunnel model is an aeroelastic model designed for the wind tunnel test condition.

  10. The impact of item-writing flaws and item complexity on examination item difficulty and discrimination value

    National Research Council Canada - National Science Library

    Bonnie R Rush; David C Rankin; Brad J White

    2016-01-01

    .... This study evaluated faculty-authored examinations to determine the impact of item-writing flaws and item complexity on the difficulty and discrimination value of examination items used to assess...

  11. Identification of developmentally appropriate screening items for disruptive behavior problems in preschoolers.

    Science.gov (United States)

    Studts, Christina R; van Zyl, Michiel A

    2013-08-01

    Screening preschool-aged children for disruptive behavior disorders is a key step in early intervention. The study goal was to identify screening items with excellent measurement properties at sub-clinical to clinical levels of disruptive behavior problems within the developmental context of preschool-aged children. Parents/caregivers of preschool-aged children (N = 900) were recruited from four pediatric primary care settings. Participants (mean age = 31, SD = 8) were predominantly female (87 %), either white (55 %) or African-American (42 %), and biological parents (88 %) of the target children. In this cross-sectional survey, participants completed a sociodemographic questionnaire and two parent-report behavioral rating scales: the PSC-17 and the BPI. Item response theory analyses provided item parameter estimates and information functions for 18 externalizing subscale items, revealing their quality of measurement along the continuum of disruptive behaviors in preschool-aged children. Of 18 investigated items, 5 items measured only low levels of disruptive behaviors among preschool-aged children. The remaining 13 items measured sub-clinical to clinical levels of disruptive behavior problems (i.e., >1.5 SD); however, 5 of these items offered less information, suggesting unreliable measurement. The remaining 8 items had high discrimination and difficulty parameters, offering considerable measurement information at sub-clinical to clinical levels of disruptive behavior problems. Behaviors measured by the 8 selected parent-report items were consistent with those identified in recent efforts to distinguish developmentally typical misbehaviors from clinically concerning behaviors among preschool-aged children. These items may have clinical utility in screening young children for disruptive behavior disorders.

  12. Caries Risk Assessment Item Importance

    Science.gov (United States)

    Chaffee, B.W.; Featherstone, J.D.B.; Gansky, S.A.; Cheng, J.; Zhan, L.

    2016-01-01

    Caries risk assessment (CRA) is widely recommended for dental caries management. Little is known regarding how practitioners use individual CRA items to determine risk and which individual items independently predict clinical outcomes in children younger than 6 y. The objective of this study was to assess the relative importance of pediatric CRA items in dental providers’ decision making regarding patient risk and in association with clinically evident caries, cross-sectionally and longitudinally. CRA information was abstracted retrospectively from electronic patient records of children initially aged 6 to 72 mo at a university pediatric dentistry clinic (n = 3,810 baseline; n = 1,315 with follow-up). The 17-item CRA form included caries risk indicators, caries protective items, and clinical indicators. Conditional random forests classification trees were implemented to identify and assign variable importance to CRA items independently associated with baseline high-risk designation, baseline evident tooth decay, and follow-up evident decay. Thirteen individual CRA items, including all clinical indicators and all but 1 risk indicator, were independently and statistically significantly associated with student/resident providers’ caries risk designation. Provider-assigned baseline risk category was strongly associated with follow-up decay, which increased from low (20.4%) to moderate (30.6%) to high/extreme risk patients (68.7%). Of baseline CRA items, before adjustment, 12 were associated with baseline decay and 7 with decay at follow-up; however, in the conditional random forests models, only the clinical indicators (evident decay, dental plaque, and recent restoration placement) and 1 risk indicator (frequent snacking) were independently and statistically significantly associated with future disease, for which baseline evident decay was the strongest predictor. In this predominantly high-risk population under caries-preventive care, more individual CRA items

  13. Australian Item Bank Program: Social Science Item Bank.

    Science.gov (United States)

    Australian Council for Educational Research, Hawthorn.

    After vigorous review, editing, and trial testing, this item bank was compiled to help secondary school teachers construct objective tests in the social sciences. Anthropology, economics, ethnic and cultural studies, geography, history, legal studies, politics, and sociology are among the topics represented. The bank consists of multiple choice…

  14. A proposal for a new Brazilian six-item version of the Edinburgh Postnatal Depression Scale

    Directory of Open Access Journals (Sweden)

    Maicon Rodrigues Albuquerque

    Full Text Available Abstract Introduction: Factor analysis of the Edinburgh Postnatal Depression Scale (EPDS could result in a shorter and easier to handle screening tool. Therefore, the aim of this study was to check and compare the metrics of two different 6-item EPDS subscales. Methods: We administered the EPDS to a total of 3,891 women who had given birth between 1 and 3 months previously. We conducted confirmatory and exploratory factor analyses and plotted receiver-operating characteristics (ROC curves to, respectively, determine construct validity, scale items' fit to the data, and ideal cutoff scores for the short versions. Results: A previously defined 6-item scale did not exhibit construct validity for our sample. Nevertheless, we used exploratory factor analysis to derive a new 6-item scale with very good construct validity. The area under the ROC curve of the new 6-item scale was 0.986 and the ideal cutoff score was ≥ 6. Conclusions: The new 6-item scale has adequate psychometric properties and similar ROC curve values to the10-item version and offers a means of reducing the cost and time taken to administer the instrument.

  15. An item response theory analysis of Harter’s self-perception profile for children or why strong clinical scales should be distrusted

    NARCIS (Netherlands)

    Egberink, I.J.L.; Meijer, R.R.

    2011-01-01

    The authors investigated the psychometric properties of the subscales of the Self-Perception Profile for Children with item response theory (IRT) models using a sample of 611 children. Results from a nonparametric Mokken analysis and a parametric IRT approach for boys (n = 268) and girls (n = 343)

  16. An Item Response Theory Analysis of Harter's Self-Perception Profile for Children or Why Strong Clinical Scales Should Be Distrusted

    Science.gov (United States)

    Egberink, Iris J. L.; Meijer, Rob R.

    2011-01-01

    The authors investigated the psychometric properties of the subscales of the Self-Perception Profile for Children with item response theory (IRT) models using a sample of 611 children. Results from a nonparametric Mokken analysis and a parametric IRT approach for boys (n = 268) and girls (n = 343) were compared. The authors found that most scales…

  17. An item response theory analysis of Harter's Self-Perception Profile for Children or why strong clinical scales should be distrusted

    NARCIS (Netherlands)

    Egberink, Iris J. L.; Meijer, Rob R.

    The authors investigated the psychometric properties of the subscales of the Self-Perception Profile for Children with item response theory (IRT) models using a sample of 611 children. Results from a nonparametric Mokken analysis and a parametric IRT approach for boys (n = 268) and girls (n = 343)

  18. Confirmatory Factor Analysis of the PKBS-2 Subscales for Assessing Social Skills and Behavioral Problems in Preschool Education

    Science.gov (United States)

    Fernandez, Maria; Benitez, Juan L.; Pichardo, M. Carmen; Fernandez, Eduardo; Justicia, Fernando; Garcia, Trinidad; Garcia-Berben, Ana; Justicia, Ana; Alba, Guadalupe

    2010-01-01

    Introduction: Different research studies point out the importance of social competence as a protective factor against antisocial behavior. They likewise alert us of the importance of having valid, reliable instruments that measure these constructs in early childhood. Method: The objective of this research is to validate the subscales of the…

  19. Validity of the Sleep Subscale of the Diagnostic Assessment for the Severely Handicapped-II (DASH-II)

    Science.gov (United States)

    Matson, Johnny L.; Malone, Carrie J.

    2006-01-01

    Currently there are no available sleep disorder measures for individuals with severe and profound intellectual disability. We, therefore, attempted to establish the external validity of the "Diagnostic Assessment for the Severely Handicapped-II" (DASH-II) sleep subscale by comparing daily observational sleep data with the responses of…

  20. Comparison of behavioral activation subscales of Gray’s original reinforcement sensitivity theory in opioid and methamphetamine dependent patients

    Directory of Open Access Journals (Sweden)

    Amir Ghaderi

    2017-10-01

    Results: The methamphetamine-dependents group had a higher BAS-DR subscale score than the opioid dependent group (P0.05. The BAS-RR scores of the methamphetamine-dependents group were higher than the other two groups (P

  1. The genetic and environmental structure of the character sub-scales of the temperament and character inventory in adolescence.

    Science.gov (United States)

    Lester, Nigel; Garcia, Danilo; Lundström, Sebastian; Brändström, Sven; Råstam, Maria; Kerekes, Nóra; Nilsson, Thomas; Cloninger, C Robert; Anckarsäter, Henrik

    2016-01-01

    The character higher order scales (self-directedness, cooperativeness, and self-transcendence) in the temperament and character inventory are important general measures of health and well-being [Mens Sana Monograph 11:16-24 (2013)]. Recent research has found suggestive evidence of common environmental influence on the development of these character traits during adolescence. The present article expands earlier research by focusing on the internal consistency and the etiology of traits measured by the lower order sub-scales of the character traits in adolescence. The twin modeling analysis of 423 monozygotic pairs and 408 same sex dizygotic pairs estimated additive genetics (A), common environmental (C), and non-shared environmental (E) influences on twin resemblance. All twins were part of the on-going longitudinal Child and Adolescent Twin Study in Sweden (CATSS). The twin modeling analysis suggested a common environmental contribution for two out of five self-directedness sub-scales (0.14 and 0.23), for three out of five cooperativeness sub-scales (0.07-0.17), and for all three self-transcendence sub-scales (0.10-0.12). The genetic structure at the level of the character lower order sub-scales in adolescents shows that the proportion of the shared environmental component varies in the trait of self-directedness and in the trait of cooperativeness, while it is relatively stable across the components of self-transcendence. The presence of this unique shared environmental effect in adolescence has implications for understanding the relative importance of interventions and treatment strategies aimed at promoting overall maturation of character, mental health, and well-being during this period of the life span.

  2. How did Danish students solve the PISA CBAS items?

    DEFF Research Database (Denmark)

    Sørensen, Helene; Andersen, Annemarie Møller

    2009-01-01

    The intention by introducing Computer-based Assessment in Science (CBAS) was to reduce the reading load and to retain the science content. CBAS succeeded in doing this but in the CBAS test results showed a significant gender difference in favour of males. This means that the computer-based test...... is not gender-neutral to the same extent as the paper-and-pencil test. Instead of that the items appear to be more difficult for girls than boys in all three countries which went through CBAS. Within the Danish context we have classified the different items and compared the results with patterns in girls...... explanation for the bigger gender difference in CBAS. The items mediate a gendered impression which influences girls more than boys. This together with the social settings around the test requires a high self confidence to score high in the test....

  3. Analysis of Correlation between an Accelerometer-Based Algorithm for Detecting Parkinsonian Gait and UPDRS Subscales

    Directory of Open Access Journals (Sweden)

    Alejandro Rodríguez-Molinero

    2017-09-01

    Full Text Available BackgroundOur group earlier developed a small monitoring device, which uses accelerometer measurements to accurately detect motor fluctuations in patients with Parkinson’s (On and Off state based on an algorithm that characterizes gait through the frequency content of strides. To further validate the algorithm, we studied the correlation of its outputs with the motor section of the Unified Parkinson’s Disease Rating Scale part-III (UPDRS-III.MethodSeventy-five patients suffering from Parkinson’s disease were asked to walk both in the Off and the On state while wearing the inertial sensor on the waist. Additionally, all patients were administered the motor section of the UPDRS in both motor phases. Tests were conducted at the patient’s home. Convergence between the algorithm and the scale was evaluated by using the Spearman’s correlation coefficient.ResultsCorrelation with the UPDRS-III was moderate (rho −0.56; p < 0.001. Correlation between the algorithm outputs and the gait item in the UPDRS-III was good (rho −0.73; p < 0.001. The factorial analysis of the UPDRS-III has repeatedly shown that several of its items can be clustered under the so-called Factor 1: “axial function, balance, and gait.” The correlation between the algorithm outputs and this factor of the UPDRS-III was −0.67 (p < 0.01.ConclusionThe correlation achieved by the algorithm with the UPDRS-III scale suggests that this algorithm might be a useful tool for monitoring patients with Parkinson’s disease and motor fluctuations.

  4. 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

  5. Unidimensional Interpretations for Multidimensional Test Items

    Science.gov (United States)

    Kahraman, Nilufer

    2013-01-01

    This article considers potential problems that can arise in estimating a unidimensional item response theory (IRT) model when some test items are multidimensional (i.e., show a complex factorial structure). More specifically, this study examines (1) the consequences of model misfit on IRT item parameter estimates due to unintended minor item-level…

  6. The impact of item-writing flaws and item complexity on examination item difficulty and discrimination value.

    Science.gov (United States)

    Rush, Bonnie R; Rankin, David C; White, Brad J

    2016-09-29

    Failure to adhere to standard item-writing guidelines may render examination questions easier or more difficult than intended. Item complexity describes the cognitive skill level required to obtain a correct answer. Higher cognitive examination items promote critical thinking and are recommended to prepare students for clinical training. This study evaluated faculty-authored examinations to determine the impact of item-writing flaws and item complexity on the difficulty and discrimination value of examination items used to assess third year veterinary students. The impact of item-writing flaws and item complexity (cognitive level I-V) on examination item difficulty and discrimination value was evaluated on 1925 examination items prepared by clinical faculty for third year veterinary students. The mean (± SE) percent correct (83.3 % ± 17.5) was consistent with target values in professional education, and the mean discrimination index (0.18 ± 0.17) was slightly lower than recommended (0.20). More than one item-writing flaw was identified in 37.3 % of questions. The most common item-writing flaws were awkward stem structure, implausible distractors, longest response is correct, and responses are series of true-false statements. Higher cognitive skills (complexity level III-IV) were required to correctly answer 38.4 % of examination items. As item complexity increased, item difficulty and discrimination values increased. The probability of writing discriminating, difficult examination items decreased when implausible distractors and all of the above were used, and increased if the distractors were comprised of a series of true/false statements. Items with four distractors were not more difficult or discriminating than items with three distractors. Preparation of examination questions targeting higher cognitive levels will increase the likelihood of constructing discriminating items. Use of implausible distractors to complete a five-option multiple choice

  7. Psychometric validation of the Taiwan Chinese version of the 25-Item National Eye Institute Visual Functioning Questionnaire.

    Science.gov (United States)

    Lin, Jen-Chieh; Chie, Wei-Chu

    2010-06-01

    To evaluate the reliability and construct validity of a Taiwan Chinese version of the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ 25) in patients with visual impairment. The NEI-VFQ 25 was translated and adapted into the Taiwan Chinese version. In total, 222 patients responded to the questionnaire. To examine reliability, Cronbach's alpha for each subscale was used as an index of internal consistency. Test-retest reliability was evaluated with intraclass correlation coefficients. Regarding construct validity, both convergent and discriminant validities were calculated by means of multi-trait analysis. Clinical validity was examined by correlation of clinical measurements and subscale scores and known-groups comparison. Finally, correlation between different subscales was examined to evaluate hypothetical relationship between subscales. Five patient groups were studied, each including participants with a single cause of visual impairment. Group 1 consisted of 53 cataract patients; group 2 included 51 subjects with glaucoma; group 3 included 36 subjects with age-related macular degeneration (ARMD); and group 4 included 48 subjects with diabetic retinopathy. Thirty-four individuals with uncorrected refractive error comprised the control group. NEI-VFQ scores (mean +/- SD) for the cataract, glaucoma, ARMD, diabetic retinopathy and control groups were: 73.5 +/- 17.1, 69.2 +/- 20.4, 62.3 +/- 23.7, 63.7 +/- 20.8 and 80.7 +/- 12.0, respectively. Item analysis revealed moderate data skewing. Cronbach's alpha coefficients of subscales ranged from 0.956 (mental health) to 0.964 (near activities). Intraclass correlation coefficients ranged from 0.41 (driving) to 0.846 (distance activities). All items passed the convergent and discriminant validity tests. Moderate correlations were detected between visual acuity and the 'general vision', 'distance activities' and 'near activities' subscales. Significant correlations were detected between visual

  8. Using a single item to measure burnout in primary care staff: a psychometric evaluation.

    Science.gov (United States)

    Dolan, Emily D; Mohr, David; Lempa, Michele; Joos, Sandra; Fihn, Stephan D; Nelson, Karin M; Helfrich, Christian D

    2015-05-01

    Burnout affects nearly half of all U.S. nurses and physicians, and has been linked to poor outcomes such as worse patient safety. The most common measure of burnout is the well-validated Maslach Burnout Inventory (MBI). However, the MBI is proprietary and carries licensing fees, posing challenges to routine or repeated assessment. To compare a non-proprietary, single-item burnout measure to a single item from the MBI Emotional Exhaustion (MBI:EE) subscale that has been validated as a standalone burnout measure. Cross-sectional online survey. A sample of primary care providers (PCPs), registered nurses, clinical associates (e.g., licensed practical nurses (LPNs), medical technicians), and administrative clerks in the Veterans Health Administration surveyed in 2012. We compared a validated one-item version of the MBI:EE and a non-proprietary single-item burnout measure used in the Physician Work Life Study. We calculated kappa statistics, sensitivity and specificity, positive predictive (PPV) and negative predictive values (NPV), and area under the receiver operator curve (AUC). We conducted analyses stratified by occupation to determine the stability of the correlation between the two measures. We analyzed responses from 5,404 participants, including 1,769 providers and 1,380 registered nurses. The prevalence of burnout was 36.7% as measured on the single MBI:EE item and 38.5% as measured on the non-proprietary single-item measure. Relative to the MBI:EE, the non-proprietary single-item measure had a correlation of 0.79, sensitivity of 83.2%, specificity of 87.4%, and AUC of 0.93 (se = 0.004). Results were similar when stratified by respondent occupation. A non-proprietary single-item measure served as a reliable substitute for the MBI:EE across occupations. Because it is non-proprietary and easy to interpret, it has logistical advantages over the one-item MBI.

  9. 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

  10. The 12-item well-being questionnaire. An evaluation of its validity and reliability in Dutch people with diabetes

    DEFF Research Database (Denmark)

    Pouwer, F; Van Der Ploeg, Henk M; Adér, Herman J

    1999-01-01

    /psychiatrist. CONCLUSIONS: The W-BQ12 appeared to be a reliable and valid measure of psychological well-being. This short instrument is easy to administer and may be considered a useful tool for both clinicians and researchers to assess the psychological well-being of patients with diabetes....... overall scale General Well-Being (GWB). RESEARCH DESIGN AND METHODS: A total of 1,472 patients with diabetes completed the W-BQ12, the Hospital Anxiety and Depression scale, and the State Trait Anxiety Inventory. Statistics covered Cronbach's alpha, Pearson's correlation, t tests, and logistic regression......OBJECTIVE: The objective of this study was to investigate the validity and reliability of the short-form 12-Item Well-Being Questionnaire (W-BQ12). The 12 items were used to construct the three 4-item subscales Negative Well-Being (NWB), Energy (ENE), and Positive Well-Being (PWB), and the 12-item...

  11. Development of a Low-Cost, Subscale Test System to Evaluate Particle Impingement Erosion in Nozzle Ablative Materials

    Science.gov (United States)

    Lansing, Matthew D.; Lawrence, Timothy W.; Gordon, Gail H. (Technical Monitor)

    2001-01-01

    This viewgraph presentation gives an overview on the development of a low-cost, subscale test system to evaluate particle impingement erosion in nozzle ablative materials. Details are given on the need for a new test bed, solid fuel torch components, solid fuel torch test, additional uses for the solid fuel torch, the development of a supersonic blast tube (SSBT), and particle impingement material discrimination.

  12. The use of Spielberger’s State-Trait Personality Inventory (trait anxiety subscale) with naval subaquatic specialists

    OpenAIRE

    Van Wijk, Charles H

    2014-01-01

    Objectives: Panic behavior poses a particular threat to the health and safety of subaquatic occupational specialists. Trait anxiety has previously been identified as a marker of panic behavior under water, and Spielberger’s State-Trait Personality Inventory (trait anxiety subscale) has been previously used to measure trait anxiety among subaquatic specialists. Using archived data, the trait anxiety scores of subaquatic specialists were analyzed to meet 3 objectives: 1stly – to develop a trait...

  13. Diagnostic Accuracy of the CASI-4R Psychosis Subscale for Children Evaluated in Pediatric Outpatient Clinics.

    Science.gov (United States)

    Rizvi, Sabeen H; Salcedo, Stephanie; Youngstrom, Eric A; Freeman, Lindsey K; Gadow, Kenneth D; Fristad, Mary A; Birmaher, Boris; Kowatch, Robert A; Horwitz, Sarah M; Frazier, Thomas W; Arnold, L Eugene; Taylor, H Gerry; Findling, Robert L

    2018-01-26

    Diagnostic accuracy of the Diagnostic and Statistical Manual of Mental Disorders-oriented Child and Adolescent Symptom Inventory (CASI-4R) Psychotic Symptoms scale was tested using receiver operating characteristic analyses to identify clinically significant psychotic symptoms. Participants were new outpatients (N = 700), ages 6.0 to 12.9 years (M = 9.7, SD = 1.8) at 9 child outpatient mental health clinics, who participated in the Longitudinal Assessment of Manic Symptoms (LAMS) Study baseline assessment. Because LAMS undersampled participants with low mania scores by design, present analyses weighted low scorers to produce unbiased estimates. Psychotic symptoms, operationally defined as a score of 3 or more for hallucinations or 4 or more for delusions based on the Schedule for Affective Disorders and Schizophrenia (K-SADS) psychosis items, occurred in 7% of youth. K-SADS diagnoses for those identified with psychotic symptoms above threshold included major depressive disorder, bipolar spectrum disorder, attention deficit/hyperactivity disorder, posttraumatic stress disorder, psychotic disorders, and autism spectrum disorder. The optimal psychosis screening cut score (maximizing sensitivity and specificity) was 2.75+ (corresponding diagnostic likelihood ratio [DiLR] = 4.29) for the parent version and 3.50+ (DiLR = 5.67) for the teacher version. The Area under the Curve for parent and teacher report was .83 and .74 (both p clinically useful for identifying psychotic symptoms in children because of its brevity and accuracy.

  14. The Child Behavior Checklist-Obsessive-Compulsive Subscale Detects Severe Psychopathology and Behavioral Problems Among School-Aged Children.

    Science.gov (United States)

    Saad, Laura O; do Rosario, Maria C; Cesar, Raony C; Batistuzzo, Marcelo C; Hoexter, Marcelo Q; Manfro, Gisele G; Shavitt, Roseli G; Leckman, James F; Miguel, Eurípedes C; Alvarenga, Pedro G

    2017-05-01

    The aims of this study were (1) to assess obsessive-compulsive symptoms (OCS) dimensionally in a school-aged community sample and to correlate them with clinical and demographical variables; (2) to determine a subgroup with significant OCS ("at-risk for OCD") using the Child Behavior Checklist (CBCL-OCS) and (3) to compare it with the rest of the sample; (4) To review the CBCL-OCS subscale properties as a screening tool for pediatric OCD. Data from the Brazilian High Risk Cohort were analyzed. The presence and severity of OCS were assessed through the CBCL-OCS subscale. DSM-IV psychiatric diagnoses were obtained by the Developmental and Well-Being Assessment. Behavioral problems were assessed using the Strengths and Difficulties Questionnaire, the Youth Strengths Inventory, and the CBCL internalizing and externalizing behavior subscales. A total of 2512 (mean age: 8.86 ± 1.84 years; 55.0% male) children were included. Moderate correlations were found between OCS severity and functional impairment (r = 0.36, p behavioral problems (p behavioral patterns and psychiatric comorbidities (e.g., tics [odds ratios, OR = 6.41, p approach suggests that the presence of OCS in children is associated with higher rates of comorbidity, behavioral problems, and impairment. The "at-risk for OCD" group defined by the CBCL revealed a group of patients phenotypically similar to full blown OCD.

  15. Sharing the cost of redundant items

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moulin, Hervé

    2014-01-01

    are network connectivity problems when an existing (possibly inefficient) network must be maintained. We axiomatize a family cost ratios based on simple liability indices, one for each agent and for each item, measuring the relative worth of this item across agents, and generating cost allocation rules......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...... additive in costs....

  16. Intact Transition Epitope Mapping (ITEM)

    Science.gov (United States)

    Yefremova, Yelena; Opuni, Kwabena F. M.; Danquah, Bright D.; Thiesen, Hans-Juergen; Glocker, Michael O.

    2017-08-01

    Intact transition epitope mapping (ITEM) enables rapid and accurate determination of protein antigen-derived epitopes by either epitope extraction or epitope excision. Upon formation of the antigen peptide-containing immune complex in solution, the entire mixture is electrosprayed to translate all constituents as protonated ions into the gas phase. There, ions from antibody-peptide complexes are separated from unbound peptide ions according to their masses, charges, and shapes either by ion mobility drift or by quadrupole ion filtering. Subsequently, immune complexes are dissociated by collision induced fragmentation and the ion signals of the "complex-released peptides," which in effect are the epitope peptides, are recorded in the time-of-flight analyzer of the mass spectrometer. Mixing of an antibody solution with a solution in which antigens or antigen-derived peptides are dissolved is, together with antigen proteolysis, the only required in-solution handling step. Simplicity of sample handling and speed of analysis together with very low sample consumption makes ITEM faster and easier to perform than other experimental epitope mapping methods.

  17. Multilayered elastic analysis formulation for surface moment loading

    CSIR Research Space (South Africa)

    Maina, JW

    2006-01-01

    Full Text Available into consideration surface moment loading. GOVERNING EQUATIONS The governing equations may be presented by using cylindrical coordinate system and assume that a circular load, with radius a , is acting on the pavement surface and the magnitude of the load varies... of Equation (1a) is the uniformly distributed vertical load, while the second item represents the load, which is anti-symmetric about the y - axis. The loading distribution obtained from Equation (1a) is a sum of uniformly distributed load and the load...

  18. Item Analysis in Introductory Economics Testing.

    Science.gov (United States)

    Tinari, Frank D.

    1979-01-01

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

  19. Towards an authoring system for item construction

    NARCIS (Netherlands)

    Rikers, Jos H.A.N.

    1988-01-01

    The process of writing test items is analyzed, and a blueprint is presented for an authoring system for test item writing to reduce invalidity and to structure the process of item writing. The developmental methodology is introduced, and the first steps in the process are reported. A historical

  20. Real and Artificial Differential Item Functioning

    Science.gov (United States)

    Andrich, David; Hagquist, Curt

    2012-01-01

    The literature in modern test theory on procedures for identifying items with differential item functioning (DIF) among two groups of persons includes the Mantel-Haenszel (MH) procedure. Generally, it is not recognized explicitly that if there is real DIF in some items which favor one group, then as an artifact of this procedure, artificial DIF…

  1. FACTOR STRUCTURE OF MF SCALES AND ITEMS.

    Science.gov (United States)

    LUNNEBORG, CLIFFORD E.; LUNNEBORG, PATRICIA W.

    FACTOR ANALYSES WERE PERFORMED UPON FOUR MASCULINITY-FEMINITY (MF) SCALES AND UPON THE 136-ITEMS COMPRISING THESE SCALES. RESULTS OF THE FIRST ANALYSIS ILLUSTRATED THE DIFFICULTY OF INTERPRETING FACTORS BASED ON HETEROGENEOUS SCALES. THE ITEM FACTORING REVEALED THE MULTIDIMENSIONALITY OF MF. CERTAIN ITEM FACTORS WERE UNCORRELATED WITH SEX STATUS…

  2. Modeling and simulation of a GOX/kerosene subscale rocket combustion chamber with film cooling

    Science.gov (United States)

    Höglauer, C.; Kniesner, B.; Knab, O.; Schlieben, G.; Kirchberger, C.; Silvestri, S.; Haidn, O. J.

    2015-12-01

    Detailed knowledge on the heat transfer mechanisms is crucial for the design of reliable and efficient rocket engines. Due to the high heat loads of the combustion chamber walls and the corrosive hot gases, film cooling is often applied supplementary or even as a primary cooling technique. Nevertheless, the dominating processes determining the film effectiveness under the conditions representative for rocket combustors are still not fully understood. In context of the national research program Transregio SFB/TRR-40, TEKAN and TARES, the Institute for Flight Propulsion (LFA) of the Technische Universität München (TUM) and Airbus Defence and Space carry out experimental and numerical investigations on heat transfer and film cooling techniques at application-relevant combustion pressures and temperatures. In this paper, results from film cooling experiments and numerical simulations with liquid and transcritical kerosene films in a water-cooled GOX/kerosene rocket combustion chamber are presented. The tests have been performed at two different combustion chamber pressures and with two different throat diameters to study the influence of Reynolds and Mach number. In the numerical investigations, a major issue has been the modeling of kerosene films in sub- and transcritical state. For the modeling Airbus Defence and Space's in-house tool, Rocflam-II has been applied. The main goal of Rocflam-II is to provide a tool package for the simulation of a wide range of rocket combustion devices, validated against experimental data. This includes the modeling of propellant injection, atomization, mixing, combustion, wall heat transfer, film modeling as well as the conjugate heat transfer into the chamber wall and the cooling channels.

  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. A Risk-Based Approach to Variable Load Configuration Validation in Steam Sterilization: Application of PDA Technical Report 1 Load Equivalence Topic.

    Science.gov (United States)

    Pavell, Anthony; Hughes, Keith A

    2010-01-01

    This article describes a method for achieving the load equivalence model, described in Parenteral Drug Association Technical Report 1, using a mass-based approach. The item and load bracketing approach allows for mixed equipment load size variation for operational flexibility along with decreased time to introduce new items to the operation. The article discusses the utilization of approximately 67 items/components (Table IV) identified for routine sterilization with varying quantities required weekly. The items were assessed for worst-case identification using four temperature-related criteria. The criteria were used to provide a data-based identification of worst-case items, and/or item equivalence, to carry forward into cycle validation using a variable load pattern. The mass approach to maximum load determination was used to bracket routine production use and allows for variable loading patterns. The result of the item mapping and load bracketing data is "a proven acceptable range" of sterilizing conditions including loading configuration and location. The application of these approaches, while initially more time/test-intensive than alternate approaches, provides a method of cycle validation with long-term benefit of ease of ongoing qualification, minimizing time and requirements for new equipment qualification for similar loads/use, and for rapid and rigorous assessment of new items for sterilization.

  5. Assessing the item response theory with covariate (IRT-C) procedure for ascertaining differential item functioning

    NARCIS (Netherlands)

    Tay, L.; Vermunt, J.K.; Wang, C.

    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

  6. 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…

  7. The quadratic relationship between difficulty of intelligence test items and their correlations with working memory.

    Science.gov (United States)

    Smolen, Tomasz; Chuderski, Adam

    2015-01-01

    Fluid intelligence (Gf) is a crucial cognitive ability that involves abstract reasoning in order to solve novel problems. Recent research demonstrated that Gf strongly depends on the individual effectiveness of working memory (WM). We investigated a popular claim that if the storage capacity underlay the WM-Gf correlation, then such a correlation should increase with an increasing number of items or rules (load) in a Gf-test. As often no such link is observed, on that basis the storage-capacity account is rejected, and alternative accounts of Gf (e.g., related to executive control or processing speed) are proposed. Using both analytical inference and numerical simulations, we demonstrated that the load-dependent change in correlation is primarily a function of the amount of floor/ceiling effect for particular items. Thus, the item-wise WM correlation of a Gf-test depends on its overall difficulty, and the difficulty distribution across its items. When the early test items yield huge ceiling, but the late items do not approach floor, that correlation will increase throughout the test. If the early items locate themselves between ceiling and floor, but the late items approach floor, the respective correlation will decrease. For a hallmark Gf-test, the Raven-test, whose items span from ceiling to floor, the quadratic relationship is expected, and it was shown empirically using a large sample and two types of WMC tasks. In consequence, no changes in correlation due to varying WM/Gf load, or lack of them, can yield an argument for or against any theory of WM/Gf. Moreover, as the mathematical properties of the correlation formula make it relatively immune to ceiling/floor effects for overall moderate correlations, only minor changes (if any) in the WM-Gf correlation should be expected for many psychological tests.

  8. The quadratic relationship between difficulty of intelligence test items and their correlations with working memory

    Directory of Open Access Journals (Sweden)

    Tomasz eSmoleń

    2015-08-01

    Full Text Available Fluid intelligence (Gf is a crucial cognitive ability that involves abstract reasoning in order to solve novel problems. Recent research demonstrated that Gf strongly depends on the individual effectiveness of working memory (WM. We investigated a popular claim that if the storage capacity underlay the WM-Gf correlation, then such a correlation should increase with an increasing number of items or rules (load in a Gf test. As often no such link is observed, on that basis the storage-capacity account is rejected, and alternative accounts of Gf (e.g., related to executive control or processing speed are proposed. Using both analytical inference and numerical simulations, we demonstrated that the load-dependent change in correlation is primarily a function of the amount of floor/ceiling effect for particular items. Thus, the item-wise WM correlation of a Gf test depends on its overall difficulty, and the difficulty distribution across its items. When the early test items yield huge ceiling, but the late items do not approach floor, that correlation will increase throughout the test. If the early items locate themselves between ceiling and floor, but the late items approach floor, the respective correlation will decrease. For a hallmark Gf test, the Raven test, whose items span from ceiling to floor, the quadratic relationship is expected, and it was shown empirically using a large sample and two types of WMC tasks. In consequence, no changes in correlation due to varying WM/Gf load, or lack of them, can yield an argument for or against any theory of WM/Gf. Moreover, as the mathematical properties of the correlation formula make it relatively immune to ceiling/floor effects for overall moderate correlations, only minor changes (if any in the WM-Gf correlation should be expected for many psychological tests.

  9. From concepts to lexical items.

    Science.gov (United States)

    Bierwisch, M; Schreuder, R

    1992-03-01

    In this paper we address the question how in language production conceptual structures are mapped onto lexical items. First we describe the lexical system in a fairly abstract way. Such a system consists of, among other things, a fixed set of basic lexical entries characterized by four groups of information: phonetic form, grammatical features, argument structure, and semantic form. A crucial assumption of the paper is that the meaning in a lexical entry has a complex internal structure composed of more primitive elements (decomposition). Some aspects of argument structure and semantic form and their interaction are discussed with respect to the issue of synonymy. We propose two different mappings involved in lexical access. One maps conceptual structures to semantic forms, and the other maps semantic forms to conceptual structures. Both mappings are context dependent and are many-to-many mappings. We present an elaboration of Levelt's (1989) model in which these processes interact with the grammatical encoder and the mental lexicon. Then we address the consequences of decomposition for processing models, especially the nature of the input of lexical access and the time course. Processing models that use the activation metaphor may have difficulties accounting for certain phenomena where a certain lemma triggers not one, but two or more word forms that have to be produced with other word forms in between.

  10. Dental responsibility loadings and the relative value of dental services.

    Science.gov (United States)

    Teusner, D N; Ju, X; Brennan, D S

    2017-09-01

    To estimate responsibility loadings for a comprehensive list of dental services, providing a standardized unit of clinical work effort. Dentists (n = 2500) randomly sampled from the Australian Dental Association membership (2011) were randomly assigned to one of 25 panels. Panels were surveyed by questionnaires eliciting responsibility loadings for eight common dental services (core items) and approximately 12 other items unique to that questionnaire. In total, loadings were elicited for 299 items listed in the Australian Dental Schedule 9th Edition. Data were weighted to reflect the age and sex distribution of the workforce. To assess reliability, regression models assessed differences in core item loadings by panel assignment. Estimated loadings were described by reporting the median and mean. Response rate was 37%. Panel composition did not vary by practitioner characteristics. Core item loadings did not vary by panel assignment. Oral surgery and endodontic service areas had the highest proportion (91%) of services with median loadings ≥1.5, followed by prosthodontics (78%), periodontics (76%), orthodontics (63%), restorative (62%) and diagnostic services (31%). Preventive services had median loadings ≤1.25. Dental responsibility loadings estimated by this study can be applied in the development of relative value scales. © 2017 Australian Dental Association.

  11. Factor Analysis of the 12-Item Zarit Burden Interview in Caregivers of Persons Diagnosed With Dementia.

    Science.gov (United States)

    Branger, Camille; O'Connell, Megan E; Morgan, Debra Gail

    2016-05-01

    The Zarit Burden Interview (ZBI) is commonly used to measure dementia caregiver burden, but its factor structure is unclear. A two-factor structure for the 12-item ZBI, "personal strain" and "role strain," has been shown, but recent data suggest that an additional factor of "guilt" is embedded in the "role strain" items. The 12-item ZBI administered to 194 informal rural and urban caregivers of persons diagnosed with dementia was analyzed using exploratory factor analysis. A two-factor structure, with item loadings consistent with previously conceptualized constructs of "personal strain" and "role strain," was found. Moreover, this factor structure was invariant to caregiver subgroups. When the predictive value of these factors was explored, only "personal strain" was important in predicting caregiver psychological distress, measured with the Brief Symptom Inventory. However, "role strain," which included the hypothesized "guilt" items, did not appear to be an important predictor of caregiver distress. © The Author(s) 2014.

  12. Effective cutoffs for detecting random, partially random, and nonrandom 350-item MMPI--a short form protocols.

    Science.gov (United States)

    Pinsoneault, Terry B

    2014-06-01

    The ability of the 350-item short form Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; Butcher et al., 1992) validity scales to detect random protocols was investigated using samples of 250 nonrandom protocols, 250 half-random protocols, and 250 all-random protocols. As the manual warns, long form cutoffs of the Variable Response Inconsistency scale (VRIN) of 75T and the Infrequency scale (F) of 90T were ineffective in detecting random protocols. Alternative cutoffs for F₁ and the truncated VRIN and F scales were investigated. Short form subscales of VRIN and F were developed to improve detection of partially random protocols. An algorithm using alternative cutoffs for the scales and the new subscales was quite effective, detecting 95% of the all-random protocols, 87% of the half-random protocols, and 98% of the nonrandom protocols. A follow-up cross-validation study was conducted that confirmed the effectiveness of the algorithm.

  13. A comparative validation of the abbreviated Apathy Evaluation Scale (AES-10) with the Neuropsychiatric Inventory apathy subscale against diagnostic criteria of apathy.

    NARCIS (Netherlands)

    Leontjevas, R.; Evers-Stephan, A.; Smalbrugge, M.; Pot, A.M.; Thewissen, V.; Gerritsen, D.L.; Koopmans, R.T.C.M.

    2012-01-01

    OBJECTIVE: To compare the Neuropsychiatric Inventory apathy subscale (NPIa) with the abbreviated Apathy Evaluation Scale (AES-10) on discriminant validity and on their performance to distinguish residents as apathetic or nonapathetic. DESIGN: Cross-sectional design. SETTING: Nursing home.

  14. Age, criterion flexibility, and item recognition.

    Science.gov (United States)

    North, Lione J; Olfman, Darlene; Caldera, Daniel R; Munoz, Emily; Light, Leah L

    2017-04-26

    We examined young and older adults' ability to flexibly adapt response criterion on a recognition test when the probability that a test item had been studied was cued by test color. One word color signaled that the probability of the test item being old was 70% and a second color signaled that the probability of the test item being new was 70%. Young and older adults demonstrated similar levels of criterion shifting in response to color cues. Moreover, although both young and older adults were slowed when test-item color incorrectly predicted test-item status, the extent of slowing did not differ across age group. Putative measures of cognitive control predicted recognition accuracy but not the degree to which criterion changed with test-item color. These results suggest that adaptive criterion shifting does not tax cognitive control or, if it does require effort, may be no more onerous for older than for young adults.

  15. Heuristics for container loading of furniture

    DEFF Research Database (Denmark)

    Egeblad, Jens; Garavelli, Claudio; Lisi, Stefano

    2010-01-01

    . In the studied company, the problem arises hundreds of times daily during transport planning. Instances may contain more than one hundred different items with irregular shapes. To solve this complex problem we apply a set of heuristics successively that each solve one part of the problem. Large items...... are combined in specific structures to ensure proper protection of the items during transportation and to simplify the problem. The solutions generated by the heuristic has an average loading utilization of 91.3% for the most general instances with average running times around 100 seconds....

  16. Development and psychometric properties of the 12-item diabetes fatalism scale.

    Science.gov (United States)

    Egede, Leonard E; Ellis, Charles

    2010-01-01

    This study describes the development and validation of the Diabetes Fatalism Scale (DFS) in adults with type 2 diabetes. Thirty-five items were derived from focus groups, literature review, and expert opinion. The items were pilot tested on 20 adults with diabetes and then administered to 216 primary care patients with type 2 diabetes to assess the validity and reliability of the scale. Exploratory factor analysis (Principal Component Analysis with Varimax rotation) yielded a 12-item scale with three subscales. Pearson's correlation was used to test the DFS's association with diabetes self-care, HbA1c and quality of life. Multiple linear regression was used to assess association between the DFS and HbA1c controlling for demographics, comorbidity and insulin use. Cronbach's alpha for the 12-item DFS scale was 0.804 indicating internal consistency. The DFS is scored in such a way that higher scores represent greater diabetes fatalism. The DFS scores were not significantly correlated with age, years of education, or diabetes duration. Whites, men, those with government or no insurance, and those with 3+ comorbid conditions had significantly higher DFS scores. DFS was significantly correlated with self management understanding (r = -0.35, p fatalism. Diabetes fatalism is associated with self-care problems, poor glycemic control, and decreased quality of life.

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

    Science.gov (United States)

    Scott, Neil W; Fayers, Peter M; Aaronson, Neil K; Bottomley, Andrew; de Graeff, Alexander; Groenvold, Mogens; Gundy, Chad; Koller, Michael; Petersen, Morten A; Sprangers, Mirjam A G

    2009-03-01

    Differential item functioning (DIF) analyses are increasingly used to evaluate health-related quality of life (HRQoL) instruments, which often include relatively short subscales. Computer simulations were used to explore how various factors including scale length affect analysis of DIF by ordinal logistic regression. Simulated data, representative of HRQoL scales with four-category items, were generated. The power and type I error rates of the DIF method were then investigated when, respectively, DIF was deliberately introduced and when no DIF was added. The sample size, scale length, floor effects (FEs) and significance level were varied. When there was no DIF, type I error rates were close to 5%. Detecting moderate uniform DIF in a two-item scale required a sample size of 300 per group for adequate (>80%) power. For longer scales, a sample size of 200 was adequate. Considerably larger sample sizes were required to detect nonuniform DIF, when there were extreme FEs or when a reduced type I error rate was required. The impact of the number of items in the scale was relatively small. Ordinal logistic regression successfully detects DIF for HRQoL instruments with short scales. Sample size guidelines are provided.

  18. An item response theory analysis of the Parenting Stress Index-Short Form with parents of children with autism spectrum disorders.

    Science.gov (United States)

    Zaidman-Zait, Anat; Mirenda, Pat; Zumbo, Bruno D; Wellington, Stephen; Dua, Vikram; Kalynchuk, Karen

    2010-11-01

    The Parenting Stress Index-Short Form (PSI-SF) is one of the most widely used instruments for measuring parenting stress in families of children with autism spectrum disorders (ASD). However, no research to date has examined the psychometric properties of the PSI-SF in a sample of parents of young children with ASD. In this regard, item response theory (IRT) can be used to estimate how much information or discrimination each item of a scale offers across the entire range of the latent variable being measured, by creating individual item information curves or profiles. The purpose of this study was to use IRT to examine the discriminability of PSI-SF items in a sample of parents of young children with ASD who experience varying levels of parental stress. The study involved the parents of 141 children with autism spectrum disorders (91.4% mothers; mean age 36.2 years) who completed the PSI-SF following diagnosis. Item characteristic curves were constructed for each of the PSI-SF items and examined with regard to item functioning. Results indicated that, for the most part, changes in parental distress severity were reflected in changes on item scores. However, several items on the subscales measuring parent-child dysfunctional interactions and child behavior difficulty functioned poorly to discriminate parents across a range of total stress severity. The parent-child dysfunctional interaction and difficult child subscales of the PSI-SF scale should be used with caution with parents of young children with ASD. More research is required to examine PSI-SF content validity, at least among parents of children with ASD and perhaps parents of children with other disabilities as well. © 2010 The Authors. Journal of Child Psychology and Psychiatry © 2010 Association for Child and Adolescent Mental Health.

  19. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan

    2014-01-01

    ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

  20. Design and Analysis of Subscale and Full-Scale Buckling-Critical Cylinders for Launch Vehicle Technology Development

    Science.gov (United States)

    Hilburger, Mark W.; Lovejoy, Andrew E.; Thornburgh, Robert P.; Rankin, Charles

    2012-01-01

    NASA s Shell Buckling Knockdown Factor (SBKF) project has the goal of developing new analysis-based shell buckling design factors (knockdown factors) and design and analysis technologies for launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale levels. This paper describes the design and analysis of three different orthogrid-stiffeNed metallic cylindrical-shell test articles. Two of the test articles are 8-ft-diameter, 6-ft-long test articles, and one test article is a 27.5-ft-diameter, 20-ft-long Space Shuttle External Tank-derived test article.

  1. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  2. Role of the Dorsal Hippocampus in Object Memory Load

    Science.gov (United States)

    Sannino, Sara; Russo, Fabio; Torromino, Giulia; Pendolino, Valentina; Calabresi, Paolo; De Leonibus, Elvira

    2012-01-01

    The dorsal hippocampus is crucial for mammalian spatial memory, but its exact role in item memory is still hotly debated. Recent evidence in humans suggested that the hippocampus might be selectively involved in item short-term memory to deal with an increasing memory load. In this study, we sought to test this hypothesis. To this aim we developed…

  3. A study of the dimensionality and measurement precision of the SCL-90-R using item response theory.

    Science.gov (United States)

    Paap, Muirne C S; Meijer, Rob R; Van Bebber, Jan; Pedersen, Geir; Karterud, Sigmund; Hellem, Frøydis M; Haraldsen, Ira R

    2011-09-01

    We used item response theory (IRT) to (a) investigate the dimensionality of the Symptom Checklist-90-Revised (SCL-90-R) in a severely disturbed patient group, (b) improve the subscales in a meaningful way and (c) investigate the measurement precision of the improved scales. The total sample comprised 3078 patients (72% women, mean age=35±9) admitted to 14 different day hospitals participating in the Norwegian Network of Personality-focused Treatment Programmes. Mokken Scale Analysis was used to investigate the dimensionality of the SCL-90-R and improve the subscales. This analysis was theory-driven: the scales were built on two start items that reflected the content of the disorder that corresponds with the specific scale. The Graded Response Model was employed to determine measurement precision. Our theory-driven IRT approach resulted in a new seven-factor solution including 60 of the 90 items clustered in seven scales: depression, agoraphobia, physical complaints, obsessive-compulsive, hostility (unchanged), distrust and psychoticism. Most of the new scales discriminated reliably between patients with moderately low scores to moderately high scores. In conclusion, we found support for the multidimensionality of the SCL-90-R in a large sample of severely disturbed patients. Copyright © 2011 John Wiley & Sons, Ltd.

  4. Reliability estimation for single dichotomous items

    NARCIS (Netherlands)

    Meijer, R.R.; Sijtsma, Klaas; Molenaar, Ivo W.

    1994-01-01

    Three methods for the estimation of the reliability of single dichotomous items are discussed. All methods are based on the assumptions of nondecreasing and nonintersecting item response functions and the Mokken model of double monotonicity. Based on analytical and Monte Carlo studies, it is

  5. Restricted Interests and Teacher Presentation of Items

    Science.gov (United States)

    Stocco, Corey S.; Thompson, Rachel H.; Rodriguez, Nicole M.

    2011-01-01

    Restricted and repetitive behavior (RRB) is more pervasive, prevalent, frequent, and severe in individuals with autism spectrum disorders (ASDs) than in their typical peers. One subtype of RRB is restricted interests in items or activities, which is evident in the manner in which individuals engage with items (e.g., repetitious wheel spinning),…

  6. 38 CFR 3.1606 - Transportation items.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Transportation items. 3... Burial Benefits § 3.1606 Transportation items. The transportation costs of those persons who come within... shipment. (6) Cost of transportation by common carrier including amounts paid as Federal taxes. (7) Cost of...

  7. Accuracy in Rating and Recommending Item Features

    NARCIS (Netherlands)

    L. Rutledge (Lloyd); N. Stash; Y. Wang (Yanjing); L. Aroyo

    2008-01-01

    textabstractThis paper discusses accuracy in processing ratings of and recommendations for item features. Such processing facilitates featurebased user navigation in recommender system interfaces. Item features, often in the form of tags, categories or meta-data, are becoming important hypertext

  8. Evaluating model assumptions in item response theory

    NARCIS (Netherlands)

    Tijmstra, J.

    2013-01-01

    This dissertation deals with the evaluation of model assumptions in the context of item response theory. Item response theory, also known as modern test theory, provides a statistical framework for the measurement of psychological constructs that cannot by observed directly, such as intelligence or

  9. The 24-item Brief HEXACO Inventory (BHI)

    NARCIS (Netherlands)

    de Vries, R.E.

    2013-01-01

    Up until now, no really short instrument that measures the six personality dimensions of the HEXACO model has been available. In two studies, I report the construction of the Brief HEXACO Inventory (BHI), which represents the 24 HEXACO facets with 1 item per facet (i.e., 4 items per domain) and

  10. Invariant Ordering of Item-Total Regressions

    Science.gov (United States)

    Tijmstra, Jesper; Hessen, David J.; van der Heijden, Peter G. M.; Sijtsma, Klaas

    2011-01-01

    A new observable consequence of the property of invariant item ordering is presented, which holds under Mokken's double monotonicity model for dichotomous data. The observable consequence is an invariant ordering of the item-total regressions. Kendall's measure of concordance "W" and a weighted version of this measure are proposed as measures for…

  11. Double Modals as Single Lexical Items.

    Science.gov (United States)

    Di Paolo, Marianna

    1989-01-01

    Study of East and West Texans' (N=62) use of double modals as single lexical items and their syntactic and semantic characteristics found that neither Aux nor subcategorization analysis could account for both single-modal and double-modal dialects. Double modals, however, could conceivably be analyzed as two-word lexical items such as idioms or…

  12. Recovery of unrehearsed items in connectionist models.

    NARCIS (Netherlands)

    Murre, J.M.J.; Atkins, P.W.B.

    1998-01-01

    When gradient-descent models with hidden units are retrained on a portion of a previously learned set of items, performance on both the relearned and unrelearned items improves. Previous explanations of this phenomenon have not adequately distinguished recovery, which is dependent on original

  13. Recovery of unrehearsed items in connectionist models

    NARCIS (Netherlands)

    Murre, J.M.J.; Atkins, P.W.B.

    1998-01-01

    When gradient-descent models with hidden units are retrained on a portion of a previously learned set of items, performance on both the relearned and unrelearned items improves. Previous explanations of this phenomenon have not adequately distinguished recovery, which is dependent on original

  14. Factoring handedness data: I. Item analysis.

    Science.gov (United States)

    Messinger, H B; Messinger, M I

    1995-12-01

    Recently in this journal Peters and Murphy challenged the validity of factor analyses done on bimodal handedness data, suggesting instead that right- and left-handers be studied separately. But bimodality may be avoidable if attention is paid to Oldfield's questionnaire format and instructions for the subjects. Two characteristics appear crucial: a two-column LEFT-RIGHT format for the body of the instrument and what we call Oldfield's Admonition: not to indicate strong preference for handedness item, such as write, unless "... the preference is so strong that you would never try to use the other hand unless absolutely forced to...". Attaining unimodality of an item distribution would seem to overcome the objections of Peters and Murphy. In a 1984 survey in Boston we used Oldfield's ten-item questionnaire exactly as published. This produced unimodal item distributions. With reflection of the five-point item scale and a logarithmic transformation, we achieved a degree of normalization for the items. Two surveys elsewhere based on Oldfield's 20-item list but with changes in the questionnaire format and the instructions, yielded markedly different item distributions with peaks at each extreme and sometimes in the middle as well.

  15. Comparison on Computed Tomography using industrial items

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    2014-01-01

    In a comparison involving 27 laboratories from 8 countries, measurements on two common industrial items, a polymer part and a metal part, were carried out using X-ray Computed Tomography. All items were measured using coordinate measuring machines before and after circulation, with reference...

  16. 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.

  17. Reaction time in adolescence, cumulative allostatic load, and symptoms of anxiety and depression in adulthood: the West of Scotland Twenty-07 Study.

    Science.gov (United States)

    Gale, Catharine R; Batty, G David; Cooper, Sally-Ann; Deary, Ian J; Der, Geoff; McEwen, Bruce S; Cavanagh, Jonathan

    2015-06-01

    To examine the relation between reaction time in adolescence and subsequent symptoms of anxiety and depression and investigate the mediating role of sociodemographic measures, health behaviors, and allostatic load. Participants were 705 members of the West of Scotland Twenty-07 Study. Choice reaction time was measured at age 16. At age 36 years, anxiety and depression were assessed with the 12-item General Health Questionnaire (GHQ) and the Hospital Anxiety and Depression Scale (HADS), and measurements were made of blood pressure, pulse rate, waist-to-hip ratio, and total and high-density lipoprotein cholesterol, C-reactive protein, albumin, and glycosolated hemoglobin from which allostatic load was calculated. In unadjusted models, longer choice reaction time at age 16 years was positively associated with symptoms of anxiety and depression at age 36 years: for a standard deviation increment in choice reaction time, regression coefficients (95% confidence intervals) for logged GHQ score, and square-root-transformed HADS anxiety and depression scores were 0.048 (0.016-0.080), 0.064 (0.009-0.118), and 0.097 (0.032-0.163) respectively. Adjustment for sex, parental social class, GHQ score at age 16 years, health behaviors at age 36 years and allostatic load had little attenuating effect on the association between reaction time and GHQ score, but weakened those between reaction time and the HADS subscales. Part of the effect of reaction time on depression was mediated through allostatic load; this mediating role was of borderline significance after adjustment. Adolescents with slower processing speed may be at increased risk for anxiety and depression. Cumulative allostatic load may partially mediate the relation between processing speed and depression.

  18. Elaborate Item Count Questioning: Why Do People Underreport in Item Count Responses?

    National Research Council Canada - National Science Library

    Takahiro Tsuchiya; Yoko Hirai

    2010-01-01

    ... `applies/does not apply' responses to each item. Because this inconsistency, which we refer to as the underreporting effect, often disturbs proper item count estimates, the causes of this effect are explored in this paper...

  19. 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.

  20. Effects of spacing of item repetitions in continuous recognition memory: does item retrieval difficulty promote item retention in older adults?

    Science.gov (United States)

    Kılıç, Aslı; Hoyer, William J; Howard, Marc W

    2013-01-01

    BACKGROUND/STUDY CONTEXT: Older adults exhibit an age-related deficit in item memory as a function of the length of the retention interval, but older adults and young adults usually show roughly equivalent benefits due to the spacing of item repetitions in continuous memory tasks. The current experiment investigates the seemingly paradoxical effects of retention interval and spacing in young and older adults using a continuous recognition memory procedure. Fifty young adults and 52 older adults gave memory confidence ratings to words that were presented once (P1), twice (P2), or three times (P3), and the effects of the lag length and retention interval were assessed at P2 and at P3, respectively. Response times at P2 were disproportionately longer for older adults than for younger adults as a function of the number of items occurring between P1 and P2, suggestive of age-related loss in item memory. Ratings of confidence in memory responses revealed that older adults remembered fewer items at P2 with a high degree of certainty. Confidence ratings given at P3 suggested that young and older adults derived equivalent benefits from the spacing between P1 and P2. Findings of this study support theoretical accounts that suggest that recursive reminding and/or item retrieval difficulty promote item retention in older adults.

  1. 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.

  2. Psychometric properties of the Arabic version of the 12-item diabetes fatalism scale.

    Science.gov (United States)

    Sukkarieh-Haraty, Ola; Egede, Leonard E; Abi Kharma, Joelle; Bassil, Maya

    2018-01-01

    There are widespread fatalistic beliefs in Arab countries, especially among individuals with diabetes. However, there is no tool to assess diabetes fatalism in this population. This study describes the processes used to create an Arabic version of the Diabetes Fatalism Scale (DFS) and examine its psychometric properties. A descriptive correlational design was used with a convenience sample of Lebanese adults (N = 274) with type 2 diabetes recruited from a major hospital in Beirut, Lebanon and by snowball sampling. The 12- item Diabetes Fatalism Scale- Arabic (12-item DFS-Ar) was back-translated from the original version, pilot tested on 22 adults with type 2 diabetes and then administered to 274 patients to assess the validity and reliability of the scale. Confirmatory factor analysis (CFA) was used to test the hypothesized factor structure. Cronbach's alpha was used to test for reliability. CFA supported the existence of the three factor hypothesis of the original DFS scale. The five items measuring "emotional distress" loaded under Factor 1, the four items measuring "spiritual coping" loaded under factor 2 and the last three items measuring "perceived self-efficacy" of the original scale loaded under Factor 3 (p fatalism. Further testing with larger and non-Lebanese Arabic population is needed.

  3. 48 CFR 252.211-7003 - Item identification and valuation.

    Science.gov (United States)

    2010-10-01

    ... to a class of items with the same form, fit, function, and interface. Parent item means the item..., and parts embedded within delivered items as specified in Attachment Number __. (2) The unique item... item identifier is used). (10) Government's unit acquisition cost. (11) Unit of measure. (e) For...

  4. 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…

  5. Designing P-Optimal Item Pools in Computerized Adaptive Tests with Polytomous Items

    Science.gov (United States)

    Zhou, Xuechun

    2012-01-01

    Current CAT applications consist of predominantly dichotomous items, and CATs with polytomously scored items are limited. To ascertain the best approach to polytomous CAT, a significant amount of research has been conducted on item selection, ability estimation, and impact of termination rules based on polytomous IRT models. Few studies…

  6. 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…

  7. AN ITEM RESPONSE MODEL WITH SINGLE PEAKED ITEM CHARACTERISTIC CURVES - THE PARELLA MODEL

    NARCIS (Netherlands)

    HOIJTINK, H; MOLENAAR, [No Value

    In this paper an item response model (the PARELLA model) designed specifically for the measurement of attitudes and preferences will be introduced. In contrast with the item response models currently used (e.g. the Rasch model and, the two and three parameter logistic model) the item characteristic

  8. 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…

  9. 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.…

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

    African Journals Online (AJOL)

    ... when using BILOG-MG V3.0. Five items fitted 2-parameter models in IRTPRO. It was recommended that the use of more than one IRT software programme offers more useful information for the choice of model that fit the data. KEYWORDS: Item Level, Diagnostics, Statistics, Model - Data Fit, Item Response Theory (IRT).

  11. Interactions Between Item Content And Group Membership on Achievement Test Items.

    Science.gov (United States)

    Linn, Robert L.; Harnisch, Delwyn L.

    The purpose of this investigation was to examine the interaction of item content and group membership on achievement test items. Estimates of the parameters of the three parameter logistic model were obtained on the 46 item math test for the sample of eighth grade students (N = 2055) participating in the Illinois Inventory of Educational Progress,…

  12. 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

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

    Science.gov (United States)

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

    2012-11-01

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

  14. Item response theory for measurement validity.

    Science.gov (United States)

    Yang, Frances M; Kao, Solon T

    2014-06-01

    Item response theory (IRT) is an important method of assessing the validity of measurement scales that is underutilized in the field of psychiatry. IRT describes the relationship between a latent trait (e.g., the construct that the scale proposes to assess), the properties of the items in the scale, and respondents' answers to the individual items. This paper introduces the basic premise, assumptions, and methods of IRT. To help explain these concepts we generate a hypothetical scale using three items from a modified, binary (yes/no) response version of the Center for Epidemiological Studies-Depression scale that was administered to 19,399 respondents. We first conducted a factor analysis to confirm the unidimensionality of the three items and then proceeded with Mplus software to construct the 2-Parameter Logic (2-PL) IRT model of the data, a method which allows for estimates of both item discrimination and item difficulty. The utility of this information both for clinical purposes and for scale construction purposes is discussed.

  15. Measuring student learning with item response theory

    Science.gov (United States)

    Lee, Young-Jin; Palazzo, David J.; Warnakulasooriya, Rasil; Pritchard, David E.

    2008-06-01

    We investigate short-term learning from hints and feedback in a Web-based physics tutoring system. Both the skill of students and the difficulty and discrimination of items were determined by applying item response theory (IRT) to the first answers of students who are working on for-credit homework items in an introductory Newtonian physics course. We show that after tutoring a shifted logistic item response function with lower discrimination fits the students’ second responses to an item previously answered incorrectly. Student skill decreased by 1.0 standard deviation when students used no tutoring between their (incorrect) first and second attempts, which we attribute to “item-wrong bias.” On average, using hints or feedback increased students’ skill by 0.8 standard deviation. A skill increase of 1.9 standard deviation was observed when hints were requested after viewing, but prior to attempting to answer, a particular item. The skill changes measured in this way will enable the use of IRT to assess students based on their second attempt in a tutoring environment.

  16. Confirmatory Factor Analysis and Multiple Linear Regression of the Neck Disability Index: Assessment If Subscales Are Equally Relevant in Whiplash and Nonspecific Neck Pain.

    Science.gov (United States)

    Croft, Arthur C; Milam, Bryce; Meylor, Jade; Manning, Richard

    2016-06-01

    Because of previously published recommendations to modify the Neck Disability Index (NDI), we evaluated the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. The purpose of the present study was to evaluate the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. Subjects who had sustained whiplash injuries of grade 2 or higher completed an NDI questionnaire. There were 123 subjects (55% female, of which 36% had recovered and 64% had chronic symptoms. NDI subscales were analyzed using confirmatory factor analysis, considering only the subscales and, secondly, using sex as an 11th variable. The subscales were also tested with multiple linear regression modeling using the total score as a target variable. When considering only the 10 NDI subscales, only a single factor emerged, with an eigenvalue of 5.4, explaining 53.7% of the total variance. Strong correlation (> .55) (P Multiple linear regression modeling revealed high internal consistency with all coefficients reaching significance (P < .0001). The 4 NDI subscales exerting the greatest effect were, in decreasing order, Sleeping, Lifting, Headaches, and Pain Intensity. A 2-factor model of the NDI is not justified based on our results, and in this population of whiplash subjects, the NDI was unidimensional, demonstrating high internal consistency and supporting the original validation study of Vernon and Mior.

  17. Elaborate Item Count Questioning: Why Do People Underreport in Item Count Responses?

    Directory of Open Access Journals (Sweden)

    Takahiro Tsuchiya

    2010-12-01

    Full Text Available The item count technique, used often to investigate illegal or socially undesirable behaviours, requires respondents to indicate merely the number of applicable items from among a list. However, the number of applicable items indicated via the item count question tends to be smaller than when it is calculated from the direct `applies/does not apply' responses to each item. Because this inconsistency, which we refer to as the underreporting effect, often disturbs proper item count estimates, the causes of this effect are explored in this paper. Web survey results revealed that the order of the response alternatives is irrelevant to the underreporting effect, and that the underreporting effect is caused by the response format in which the item count question requests merely the number of applicable items and not the number of non-applicable items. It is also shown that the magnitude of the underreporting effect decreases when the respondents are asked to indicate the numbers of both applicable and non-applicable items, which we refer to as elaborate item count questioning.

  18. NHRIC (National Health Related Items Code)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Health Related Items Code (NHRIC) is a system for identification and numbering of marketed device packages that is compatible with other numbering...

  19. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  20. Extending item response theory to online homework

    Directory of Open Access Journals (Sweden)

    Gerd Kortemeyer

    2014-05-01

    Full Text Available Item response theory (IRT becomes an increasingly important tool when analyzing “big data” gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for scientists and engineers, the study compares outcomes from IRT analyses of exam and homework data, and then proceeds to investigate the effects of each confounding factor introduced in the online realm. It is found that IRT yields the correct trends for learner ability and meaningful item parameters, yet overall agreement with exam data is moderate. It is also found that learner ability and item discrimination is robust over a wide range with respect to model assumptions and introduced noise. Item difficulty is also robust, but over a narrower range.

  1. 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.

  2. Clinical utility of the MMPI-A content scales and Harris-Lingoes subscales in the assessment of suicidal risk factors in psychiatric adolescents.

    Science.gov (United States)

    Kopper, B A; Osman, A; Osman, J R; Hoffman, J

    1998-02-01

    This study of 143 inpatient adolescents (68 boys and 75 girls) investigated the clinical utility of the MMPI-A in assessing suicidal risk factors by examining the unique contribution of the content scales and Harris-Lingoes subscales beyond what is provided by the basic clinical scales. The results of the regression analyses indicated that for boys, the Depression, Psychopathic Deviate and Hypomania scales; Alienation and Anxiety content scales: and Subjective Depression. Self Alienation, Imperturbability, and Amorality Harris-Lingoes subscales contributed significantly to the prediction of suicide probability. For girls, the Depression, Psychopathic Deviate, and Hypomania scales; Family Problems, Conduct Problems, School Problems, Depression, and Social Discomfort content scales; and the Subjective Depression, Self Alienation, Psychomotor Acceleration, and Imperturbability Harris-Lingoes subscales contributed significantly to the prediction of suicide probability.

  3. The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly

    Science.gov (United States)

    2000-01-01

    The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly over a dry lakebed runway during a captive-carry test flight from NASA's Dryden Flight Research Center, Edwards, California. The X-40 is attached to a sling which is suspended from the CH-47 by a 110-foot-long cable during the tests, while a small parachute trails behind to provide stability. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. The X-37 will be carried into space aboard a space shuttle and then released to perform various maneuvers and a controlled re-entry through the Earth's atmosphere to an airplane-style landing on a runway, controlled entirely by pre-programmed computer software.

  4. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    Directory of Open Access Journals (Sweden)

    Canfield T.R.

    2011-01-01

    Full Text Available We have extended the Sub-Scale Dynamics (SSD closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  5. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  6. Analysis of the laser ignition of methane/oxygen mixtures in a sub-scale rocket combustion chamber

    Science.gov (United States)

    Wohlhüter, Michael; Zhukov, Victor P.; Sender, Joachim; Schlechtriem, Stefan

    2017-06-01

    The laser ignition of methane/oxygen mixtures in a sub-scale rocket combustion chamber has been investigated numerically and experimentally. The ignition test case used in the present paper was generated during the In-Space Propulsion project (ISP-1), a project focused on the operation of propulsion systems in space, the handling of long idle periods between operations, and multiple reignitions under space conditions. Regarding the definition of the numerical simulation and the suitable domain for the current model, 2D and 3D simulations have been performed. Analysis shows that the usage of a 2D geometry is not suitable for this type of simulation, as the reduction of the geometry to a 2D domain significantly changes the conditions at the time of ignition and subsequently the flame development. The comparison of the numerical and experimental results shows a strong discrepancy in the pressure evolution and the combustion chamber pressure peak following the laser spark. The detailed analysis of the optical Schlieren and OH data leads to the conclusion that the pressure measurement system was not able to capture the strong pressure increase and the peak value in the combustion chamber during ignition. Although the timing in flame development following the laser spark is not captured appropriately, the 3D simulations reproduce the general ignition phenomena observed in the optical measurement systems, such as pressure evolution and injector flow characteristics.

  7. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Alan K [Los Alamos National Laboratory; Shashkov, Mikhail J [Los Alamos National Laboratory; Fung, Jimmy [Los Alamos National Laboratory; Canfield, Thomas R [Los Alamos National Laboratory; Kamm, James R [SNLA

    2010-10-14

    We have extended the Sub-Scale Dynamics (SSD) closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT) approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  8. Psychometric properties of the 7-item game addiction scale among french and German speaking adults.

    Science.gov (United States)

    Khazaal, Yasser; Chatton, Anne; Rothen, Stephane; Achab, Sophia; Thorens, Gabriel; Zullino, Daniele; Gmel, Gerhard

    2016-05-10

    The 7-item Game Addiction Scale (GAS) is a used to screen for addictive game use. Both cross cross-linguistic validation and validation in French and German is needed in adult samples. The objective of the study is to assess the factorial structure of the French and German versions of the GAS among adults. Two samples of men from French (N = 3318) and German (N = 2665) language areas of Switzerland were assessed with the GAS, the Major Depression Inventory (MDI), the Brief Sensation Seeking Scale, and the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ-50-cc). They were also assessed for cannabis and alcohol use. The internal consistency of the scale was satisfactory (Cronbach α = 0.85). A one-factor solution was found in both samples. Small and positive associations were found between GAS scores and the MDI, as well as the Neuroticism-Anxiety and Aggression-Hostility subscales of the ZKPQ-50-cc. A small negative association was found with the ZKPQ-50-cc Sociability subscale. The GAS, in its French and German versions, is appropriate for the assessment of game addiction among adults.

  9. Prevalence and predictors of orthorexia nervosa among German students using the 21-item-DOS.

    Science.gov (United States)

    Depa, Julia; Schweizer, Jenny; Bekers, Sandra-Kristin; Hilzendegen, Carolin; Stroebele-Benschop, Nanette

    2017-03-01

    Orthorexia nervosa (ON) describes the constant pathological preoccupation with "healthy" nutrition. The current results regarding the prevalence of ON differ widely possibly because of invalid measurement tools. This study aimed to investigate ON prevalence in a sample of German students and to examine age, gender, semester, and nutritional knowledge as potential predictors of ON by comparing nutrition science (NS) with economics (ES) students. A total of 446 university students participated in the survey (NS 188, ES 268). ON was determined using the 21-item-DOS, which is a well-constructed, validated, and reliability-tested questionnaire. Age, gender, and semester were also assessed. Of the total sample, 3.3 % were classified as having ON and 9.0 % were at risk of developing ON. Older students scored significantly higher on the subscale "avoidance of additives" compared with younger students and students of lower semester suffered significantly more often from ON than students of higher semester. In addition, comparing field of study showed no significant difference in the prevalence of ON or the risk of developing ON between female NS and ES students. However, mean values for the three DOS subscales were higher among female NS students, albeit far below values indicating pathological behavior. The prevalence of ON appears to be low in this sample of German university students. Female NS students do not seem to have higher prevalence of ON or risk of developing ON.

  10. 49 CFR 575.103 - Truck-camper loading.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Truck-camper loading. 575.103 Section 575.103... Items § 575.103 Truck-camper loading. (a) Scope. This section requires manufacturers of slide-in campers... also requires manufacturers of trucks that would accommodate slide-in campers to specify the cargo...

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

    Directory of Open Access Journals (Sweden)

    Yoon Soo ePark

    2016-02-01

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

  12. Working memory load attenuates emotional enhancement in recognition memory

    Directory of Open Access Journals (Sweden)

    Ewa Aurelia Miendlarzewska

    2013-03-01

    Full Text Available Emotionally arousing stimuli are perceived and remembered better than neutral stimuli. Under threat, this negativity bias is further increased. We investigated whether working memory load can attenuate incidental memory for emotional images. Two groups of participants performed the N-back task with two working memory load levels. In one group, we induced anxiety using a threat-of-shock paradigm to increase attentional processing of negative information. During task performance we incidentally and briefly flashed emotional distracter images which prolonged response times in both load conditions. A subsequent unannounced immediate recognition memory test revealed that when load at exposure had been low, recognition was better for negative items in both participant groups. This enhancement, however, was attenuated under high load, leaving performance on neutral items unchanged regardless of the threat-of-shock manipulation. We conclude that both in threat and in normal states working memory load at exposure can attenuate immediate emotional memory enhancement.

  13. Using Deterministic, Gated Item Response Theory Model to detect test cheating due to item compromise.

    Science.gov (United States)

    Shu, Zhan; Henson, Robert; Luecht, Richard

    2013-07-01

    The Deterministic, Gated Item Response Theory Model (DGM, Shu, Unpublished Dissertation. The University of North Carolina at Greensboro, 2010) is proposed to identify cheaters who obtain significant score gain on tests due to item exposure/compromise by conditioning on the item status (exposed or unexposed items). A "gated" function is introduced to decompose the observed examinees' performance into two distributions (the true ability distribution determined by examinees' true ability and the cheating distribution determined by examinees' cheating ability). Test cheaters who have score gain due to item exposure are identified through the comparison of the two distributions. Hierarchical Markov Chain Monte Carlo is used as the model's estimation framework. Finally, the model is applied in a real data set to illustrate how the model can be used to identify examinees having pre-knowledge on the exposed items.

  14. A strategy for optimizing item-pool management

    NARCIS (Netherlands)

    Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

    2006-01-01

    Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

  15. Loglinear multidimensional IRT models for polytomously scired Items

    NARCIS (Netherlands)

    Kelderman, Henk

    1988-01-01

    A loglinear item response theory (IRT) model is proposed that relates polytomously scored item responses to a multidimensional latent space. Each item may have a different response function where each item response may be explained by one or more latent traits. Item response functions may follow a

  16. Subscale Carbon-Carbon Nozzle Extension Development and Hot Fire Testing in Support of Upper Stage Liquid Rocket Engines

    Science.gov (United States)

    Gradl, Paul; Valentine, Peter; Crisanti, Matthew; Greene, Sandy Elam

    2016-01-01

    Upper stage and in-space liquid rocket engines are optimized for performance through the use of high area ratio nozzles to fully expand combustion gases to low exit pressures increasing exhaust velocities. Due to the large size of such nozzles and the related engine performance requirements, carbon-carbon (C/C) composite nozzle extensions are being considered for use in order to reduce weight impacts. NASA and industry partner Carbon-Carbon Advanced Technologies (C-CAT) are working towards advancing the technology readiness level of large-scale, domestically-fabricated, C/C nozzle extensions. These C/C extensions have the ability to reduce the overall costs of extensions relative to heritage metallic and composite extensions and to decrease weight by 50%. Material process and coating developments have advanced over the last several years, but hot fire testing to fully evaluate C/C nozzle extensions in relevant environments has been very limited. NASA and C-CAT have designed, fabricated and hot fire tested multiple subscale nozzle extension test articles of various C/C material systems, with the goal of assessing and advancing the manufacturability of these domestically producible materials as well as characterizing their performance when subjected to the typical environments found in a variety of liquid rocket and scramjet engines. Testing at the MSFC Test Stand 115 evaluated heritage and state-of-the-art C/C materials and coatings, demonstrating the capabilities of the high temperature materials and their fabrication methods. This paper discusses the design and fabrication of the 1.2k-lbf sized carbon-carbon nozzle extensions, provides an overview of the test campaign, presents results of the hot fire testing, and discusses potential follow-on development work.

  17. 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.

  18. Measurement equivalence of seven selected items of posttraumatic growth between black and white adult survivors of Hurricane Katrina.

    Science.gov (United States)

    Rhodes, Alison M; Tran, Thanh V

    2013-02-01

    This study examined the equivalence or comparability of the measurement properties of seven selected items measuring posttraumatic growth among self-identified Black (n = 270) and White (n = 707) adult survivors of Hurricane Katrina, using data from the Baseline Survey of the Hurricane Katrina Community Advisory Group Study. Internal consistency reliability was equally good for both groups (Cronbach's alphas = .79), as were correlations between individual scale items and their respective overall scale. Confirmatory factor analysis of a congeneric measurement model of seven selected items of posttraumatic growth showed adequate measures of fit for both groups. The results showed only small variation in magnitude of factor loadings and measurement errors between the two samples. Tests of measurement invariance showed mixed results, but overall indicated that factor loading, error variance, and factor variance were similar between the two samples. These seven selected items can be useful for future large-scale surveys of posttraumatic growth.

  19. Complex Relationships Among Masculine Norms and Health/Well-Being Outcomes: Correlation Patterns of the Conformity to Masculine Norms Inventory Subscales.

    Science.gov (United States)

    Gerdes, Zachary T; Levant, Ronald F

    2018-03-01

    The Conformity to Masculine Norms Inventory (CMNI) is a widely used multidimensional scale. Studies using the CMNI most often report only total scale scores, which are predominantly associated with negative outcomes. Various studies since the CMNI's inception in 2003 using subscales have reported both positive and negative outcomes. The current content analysis examined studies ( N = 17) correlating the 11 subscales with 63 criterion variables across 7 categories. Most findings were consistent with past research using total scale scores that reported negative outcomes. For example, conformity to masculine norms has been inversely related to help-seeking and positively correlated with concerning health variables, such as substance use. Nonetheless, past reliance on total scores has obscured the complexity of associations with the CMNI in that 30% of the findings in the present study reflected positive outcomes, particularly for health promotion. Subscales differed in their relationships with various outcomes: for one subscale they were predominantly positive, but six others were mostly negative. The situational and contextual implications of conformity to masculine norms and their relationships to positive and negative outcomes are discussed.

  20. Toward defining a cutoff score for elevated fear of hypoglycemia on the hypoglycemia fear survey worry subscale in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Hajós, Tibor R S; Polonsky, William H; Pouwer, Frans

    2014-01-01

    OBJECTIVE To determine a cutoff score for clinically meaningful fear of hypoglycemia (FoH) on the Hypoglycemia Fear Survey Worry subscale (HFS-W). RESEARCH DESIGN AND METHODS Data on the HFS-W, history of hypoglycemia, emotional well-being (World Health Organization-5 well-being index...

  1. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  2. An item selection procedure to maximise scale reliability and validity

    Directory of Open Access Journals (Sweden)

    J. Raubenheimer

    2004-10-01

    Full Text Available Wille (1996 proposed an item selection strategy which may be used to maximise, first, the internal consistency and, next, the convergent and discriminant validity of items in multi-dimensional Likert-type questionnaires or scales. In terms of his strategy, the latter aspects of validity are maximised by means of exploratory factor analyses. In this article, it is done by means of Tateneni, Mels, Cudeck and Browne’s (2001 Comprehensive Exploratory Factor Analysis (CEFA program which implements exploratory factor analysis, but provides the advantages of standard confirmatory factor analysis (e.g., the computation of the standard errors of the rotated factor loadings and measures of “model" fit. The benefits that accrue by using this incremental approach are demonstrated in terms of Allport and Ross’ (1967 Religious Orientation Scale, a widely-used psychological instrument. Opsomming Wille (1996 het ’n itemseleksiestrategie voorgestel om eerstens die interne konsekwentheid, en tweedens die konvergente en divergente geldigheid van items in multidimensionele Likert-tipe vraelyste of skale te maksimeer. Volgens sy strategie word laasgenoemde aspekte van geldigheid deur middel van eksploratiewe faktorontledings gemaksimeer. In hierdie artikel, sal dit gedoen word deur Tateneni, Mels, Cudeck en Browne (2001 se program vir Omvattende Eksploratiewe Faktorontleding (CEFA te gebruik, wat eksploratiewe faktorontleding aanwend, maar ook die voordele van gewone, bevestigende faktorontleding (bv., die berekening van die standaardfoute van die geroteerde faktorbeladings en indekse van modelpassing bied. Die voordele wat spruit uit die toepassing van hierdie inkrementele benadering word gedemonstreer aan die hand van Allport en Ross (1967 se Religious Orientation Scale, ’n gewilde sielkundige meetintrument.

  3. Item diagnostics in multivariate discrete data.

    Science.gov (United States)

    Maydeu-Olivares, Alberto; Liu, Yang

    2015-06-01

    Researchers who evaluate the fit of psychometric models to binary or multinomial items often look at univariate and bivariate residuals to determine how a poorly fitting model can be improved. There is a class of z statistics and also a class of generalized X₂ statistics that can be used for examining these marginal fits. We describe these statistics and compare them with regard to the control of Type I error and statistical power. We show how the class of z statistics can be extended to accommodate items with multinomial response options. We provide guidelines for the use of these statistics, including how to control for multiple testing, and present 2 detailed examples. Using the root mean square error of approximation (RMSEA) for discrete data to adjudge fit, the examples illustrate how the use of these methods can dramatically improve the fit of item response theory models to widely used measures in personality and clinical psychology. (c) 2015 APA, all rights reserved).

  4. Control of Suspect/Counterfeit and Defective Items

    Energy Technology Data Exchange (ETDEWEB)

    Sheriff, Marnelle L.

    2013-09-03

    This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

  5. Development and assessment of floor and ceiling items for the PROMIS physical function item bank.

    Science.gov (United States)

    Bruce, Bonnie; Fries, James; Lingala, Bharathi; Hussain, Yusra Nazar; Krishnan, Eswar

    2013-10-03

    Disability and Physical Function (PF) outcome assessment has had limited ability to measure functional status at the floor (very poor functional abilities) or the ceiling (very high functional abilities). We sought to identify, develop and evaluate new floor and ceiling items to enable broader and more precise assessment of PF outcomes for the NIH Patient-Reported-Outcomes Measurement Information System (PROMIS). We conducted two cross-sectional studies using NIH PROMIS item improvement protocols with expert review, participant survey and focus group methods. In Study 1, respondents with low PF abilities evaluated new floor items, and those with high PF abilities evaluated new ceiling items for clarity, importance and relevance. In Study 2, we compared difficulty ratings of new floor items by low functioning respondents and ceiling items by high functioning respondents to reference PROMIS PF-10 items. We used frequencies, percentages, means and standard deviations to analyze the data. In Study 1, low (n = 84) and high (n = 90) functioning respondents were mostly White, women, 70 years old, with some college, and disability scores of 0.62 and 0.30. More than 90% of the 31 new floor and 31 new ceiling items were rated as clear, important and relevant, leaving 26 ceiling and 30 floor items for Study 2. Low (n = 246) and high (n = 637) functioning Study 2 respondents were mostly White, women, 70 years old, with some college, and Health Assessment Questionnaire (HAQ) scores of 1.62 and 0.003. Compared to difficulty ratings of reference items, ceiling items were rated to be 10% more to greater than 40% more difficult to do, and floor items were rated to be about 12% to nearly 90% less difficult to do. These new floor and ceiling items considerably extend the measurable range of physical function at either extreme. They will help improve instrument performance in populations with broad functional ranges and those concentrated at one or the other extreme ends of

  6. Graphical modeling for item difficulty in medical faculty exams ...

    African Journals Online (AJOL)

    charts. Conclusion: The control charts have the advantage for classifying items as acceptable or unacceptable based on item difficulty criteria. Key words: Item difficulty, quality control, statistical process control, variable control charts ...

  7. 10-MWe solar-thermal central-receiver pilot plant, solar-facilities design integration: plant-support subsystem procurement documentation (RADL Item 7-44D)

    Energy Technology Data Exchange (ETDEWEB)

    1980-09-01

    Purchase specifications are given for the specific long lead items to be procured for the 10 MWe Solar Pilot Plant. The hardware is grouped into two categories: 480 Volt Load Center and 480 Volt Motor Control Centers; and Power, Control and Instrumentation Cable. The purchase orders for each procurement are included. Need dates for each item are identified. (LEW)

  8. Algorithmic test design using classical item parameters

    OpenAIRE

    van der Linden, Willem J.; Adema, Jos J.

    1988-01-01

    Two optimalization models for the construction of tests with a maximal value of coefficient alpha are given. Both models have a linear form and can be solved by using a branch-and-bound algorithm. The first model assumes an item bank calibrated under the Rasch model and can be used, for instance, when classical test theory has to serve as an interface between the item bank system and a user not familiar with modern test theory. Maximization of alpha was obtained by inserting a special constra...

  9. Using structural equation modeling to detect response shifts and true change in discrete variables: an application to the items of the SF-36.

    Science.gov (United States)

    Verdam, Mathilde G E; Oort, Frans J; Sprangers, Mirjam A G

    2016-06-01

    The structural equation modeling (SEM) approach for detection of response shift (Oort in Qual Life Res 14:587-598, 2005. doi: 10.1007/s11136-004-0830-y ) is especially suited for continuous data, e.g., questionnaire scales. The present objective is to explain how the SEM approach can be applied to discrete data and to illustrate response shift detection in items measuring health-related quality of life (HRQL) of cancer patients. The SEM approach for discrete data includes two stages: (1) establishing a model of underlying continuous variables that represent the observed discrete variables, (2) using these underlying continuous variables to establish a common factor model for the detection of response shift and to assess true change. The proposed SEM approach was illustrated with data of 485 cancer patients whose HRQL was measured with the SF-36, before and after start of antineoplastic treatment. Response shift effects were detected in items of the subscales mental health, physical functioning, role limitations due to physical health, and bodily pain. Recalibration response shifts indicated that patients experienced relatively fewer limitations with "bathing or dressing yourself" (effect size d = 0.51) and less "nervousness" (d = 0.30), but more "pain" (d = -0.23) and less "happiness" (d = -0.16) after antineoplastic treatment as compared to the other symptoms of the same subscale. Overall, patients' mental health improved, while their physical health, vitality, and social functioning deteriorated. No change was found for the other subscales of the SF-36. The proposed SEM approach to discrete data enables response shift detection at the item level. This will lead to a better understanding of the response shift phenomena at the item level and therefore enhances interpretation of change in the area of HRQL.

  10. Food item use by coyote sex and age classes

    Energy Technology Data Exchange (ETDEWEB)

    Cypher, B.L.; Spencer, K.A.; Scrivner, J.H.

    1995-10-01

    Food item use by coyotes was compared between sexes and among age classes at the Naval Petroleum Reserves, California. Item use did not differ significantly between males and females. Although leporid was the item most frequently used by all age classes, item use differed significantly between pups (< 1 year), yearlings (1 year), and adults (> 1 year), probably due to differential use of secondary items. Variation in item use among age classes could potentially bias results of coyote food habit studies.

  11. Assessing Scientific Reasoning: A Comprehensive Evaluation of Item Features That Affect Item Difficulty

    Science.gov (United States)

    Stiller, Jurik; Hartmann, Stefan; Mathesius, Sabrina; Straube, Philipp; Tiemann, Rüdiger; Nordmeier, Volkhard; Krüger, Dirk; Upmeier zu Belzen, Annette

    2016-01-01

    The aim of this study was to improve the criterion-related test score interpretation of a text-based assessment of scientific reasoning competencies in higher education by evaluating factors which systematically affect item difficulty. To provide evidence about the specific demands which test items of various difficulty make on pre-service…

  12. A Comparison of the 27-Item and 12-Item Intolerance of Uncertainty Scales

    Science.gov (United States)

    Khawaja, Nigar G.; Yu, Lai Ngo Heidi

    2010-01-01

    The 27-item Intolerance of Uncertainty Scale (IUS) has become one of the most frequently used measures of Intolerance of Uncertainty. More recently, an abridged, 12-item version of the IUS has been developed. The current research used clinical (n = 50) and non-clinical (n = 56) samples to examine and compare the psychometric properties of both…

  13. Evaluating Item Discrimination Power of WHOQOL-BREF from an Item Response Model Perspectives

    Science.gov (United States)

    Lin, Ting Hsiang; Yao, Grace

    2009-01-01

    Quality of life (QOL) has become an important component of health. By using the methodology of psychometric theory, we examine the item properties of the WHOQOL-BRIEF. Samejima's graded response model with natural metrics of the logistic response function was fitted. The results showed items with negative natures were less discriminating. Items…

  14. Modeling Local Item Dependence in Cloze and Reading Comprehension Test Items Using Testlet Response Theory

    Science.gov (United States)

    Baghaei, Purya; Ravand, Hamdollah

    2016-01-01

    In this study the magnitudes of local dependence generated by cloze test items and reading comprehension items were compared and their impact on parameter estimates and test precision was investigated. An advanced English as a foreign language reading comprehension test containing three reading passages and a cloze test was analyzed with a…

  15. Developing Multidimensional Likert Scales Using Item Factor Analysis: The Case of Four-Point Items

    Science.gov (United States)

    Asún, Rodrigo A.; Rdz-Navarro, Karina; Alvarado, Jesús M.

    2016-01-01

    This study compares the performance of two approaches in analysing four-point Likert rating scales with a factorial model: the classical factor analysis (FA) and the item factor analysis (IFA). For FA, maximum likelihood and weighted least squares estimations using Pearson correlation matrices among items are compared. For IFA, diagonally weighted…

  16. Construct Validity and Reliability of the SARA Gait and Posture Sub-scale in Early Onset Ataxia

    Directory of Open Access Journals (Sweden)

    Tjitske F. Lawerman

    2017-12-01

    Full Text Available Aim: In children, gait and posture assessment provides a crucial marker for the early characterization, surveillance and treatment evaluation of early onset ataxia (EOA. For reliable data entry of studies targeting at gait and posture improvement, uniform quantitative biomarkers are necessary. Until now, the pediatric test construct of gait and posture scores of the Scale for Assessment and Rating of Ataxia sub-scale (SARA is still unclear. In the present study, we aimed to validate the construct validity and reliability of the pediatric (SARAGAIT/POSTURE sub-scale.Methods: We included 28 EOA patients [15.5 (6–34 years; median (range]. For inter-observer reliability, we determined the ICC on EOA SARAGAIT/POSTURE sub-scores by three independent pediatric neurologists. For convergent validity, we associated SARAGAIT/POSTURE sub-scores with: (1 Ataxic gait Severity Measurement by Klockgether (ASMK; dynamic balance, (2 Pediatric Balance Scale (PBS; static balance, (3 Gross Motor Function Classification Scale -extended and revised version (GMFCS-E&R, (4 SARA-kinetic scores (SARAKINETIC; kinetic function of the upper and lower limbs, (5 Archimedes Spiral (AS; kinetic function of the upper limbs, and (6 total SARA scores (SARATOTAL; i.e., summed SARAGAIT/POSTURE, SARAKINETIC, and SARASPEECH sub-scores. For discriminant validity, we investigated whether EOA co-morbidity factors (myopathy and myoclonus could influence SARAGAIT/POSTURE sub-scores.Results: The inter-observer agreement (ICC on EOA SARAGAIT/POSTURE sub-scores was high (0.97. SARAGAIT/POSTURE was strongly correlated with the other ataxia and functional scales [ASMK (rs = -0.819; p < 0.001; PBS (rs = -0.943; p < 0.001; GMFCS-E&R (rs = -0.862; p < 0.001; SARAKINETIC (rs = 0.726; p < 0.001; AS (rs = 0.609; p = 0.002; and SARATOTAL (rs = 0.935; p < 0.001]. Comorbid myopathy influenced SARAGAIT/POSTURE scores by concurrent muscle weakness, whereas comorbid myoclonus predominantly influenced

  17. TARGET/CRYOCHIL - THERMODYNAMIC ANALYSIS AND SUBSCALE MODELING OF SPACE-BASED ORBIT TRANSFER VEHICLE CRYOGENIC PROPELLANT RESUPPLY

    Science.gov (United States)

    Defelice, D. M.

    1994-01-01

    The resupply of the cryogenic propellants is an enabling technology for space-based transfer vehicles. As part of NASA Lewis's ongoing efforts in micro-gravity fluid management, thermodynamic analysis and subscale modeling techniques have been developed to support an on-orbit test bed for cryogenic fluid management technologies. These efforts have been incorporated into two FORTRAN programs, TARGET and CRYOCHIL. The TARGET code is used to determine the maximum temperature at which the filling of a given tank can be initiated and subsequently filled to a specified pressure and fill level without venting. The main process is the transfer of the energy stored in the thermal mass of the tank walls into the inflowing liquid. This process is modeled by examining the end state of the no-vent fill process. This state is assumed to be at thermal equilibrium between the tank and the fluid which is well mixed and saturated at the tank pressure. No specific assumptions are made as to the processes or the intermediate thermodynamic states during the filling. It is only assumed that the maximum tank pressure occurs at the final state. This assumption implies that, during the initial phases of the filling, the injected liquid must pass through the bulk vapor in such a way that it absorbs a sufficient amount of its superheat so that moderate tank pressures can be maintained. It is believed that this is an achievable design goal for liquid injection systems. TARGET can be run with any fluid for which the user has a properties data base. Currently it will only run for hydrogen, oxygen, and nitrogen since pressure-enthalpy data sets have been included for these fluids only. CRYOCHIL's primary function is to predict the optimum liquid charge to be injected for each of a series of charge-hold-vent chilldown cycles. This information can then be used with specified mass flow rates and valve response times to control a liquid injection system for tank chilldown operations. This will

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    OBJECTIVE: To improve measurement precision, the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group is developing an item bank for computerized adaptive testing (CAT) of emotional functioning (EF). The item bank will be within the conceptual framework...... of the widely used EORTC Quality of Life questionnaire (QLQ-C30). STUDY DESIGN AND SETTING: On the basis of literature search and evaluations by international samples of experts and cancer patients, 38 candidate items were developed. The psychometric properties of the items were evaluated in a large...... that 24 items could be included in a unidimensional IRT model. DIF did not seem to have any significant impact on the estimation of EF. Evaluations indicated that the CAT measure may reduce sample size requirements by up to 50% compared to the QLQ-C30 EF scale without reducing power. CONCLUSION...

  19. Aging and Confidence Judgments in Item Recognition

    Science.gov (United States)

    Voskuilen, Chelsea; Ratcliff, Roger; McKoon, Gail

    2018-01-01

    We examined the effects of aging on performance in an item-recognition experiment with confidence judgments. A model for confidence judgments and response time (RTs; Ratcliff & Starns, 2013) was used to fit a large amount of data from a new sample of older adults and a previously reported sample of younger adults. This model of confidence…

  20. Items of interest from recent ornithological literature

    African Journals Online (AJOL)

    hereby introduce a new feature for Scopus: Items of interest from recent ornithological literature. We hope to have this feature in all forthcoming issues of Scopus, switching between topics based on interest and articles received. Besides the Editorial Board occasionally soliciting articles, we welcome pieces from interested ...

  1. The Fantastic Four of Mathematics Assessment Items

    Science.gov (United States)

    Greenlees, Jane

    2011-01-01

    In this article, the author makes reference to four comic book characters to make the point that together they are a formidable team, but on their own they are vulnerable. She examines the four components of mathematics assessment items and the need for implicit instruction within the classroom for student success. Just like the "Fantastic Four"…

  2. Modeling the Discrimination Power of Physics Items

    Science.gov (United States)

    Mesic, Vanes

    2011-01-01

    For the purposes of tailoring physics instruction in accordance with the needs and abilities of the students it is useful to explore the knowledge structure of students of different ability levels. In order to precisely differentiate the successive, characteristic states of student achievement it is necessary to use test items that possess…

  3. Item-Specific Gender Differences in Confidence.

    Science.gov (United States)

    Foote, Chandra J.

    Very little research has been performed which examines gender differences in confidence in highly specified situations. More generalized studies consistently suggest that women are less confident than men (i.e. Sadker and Sadker, 1994). The few studies of gender differences in item-specific conditions indicate that men tend to be more confident in…

  4. Guide to Mathematics Released Items: Understanding Scoring

    Science.gov (United States)

    Partnership for Assessment of Readiness for College and Careers, 2017

    2017-01-01

    The Partnership for Assessment of Readiness for College and Careers (PARCC) mathematics items measure critical thinking, mathematical reasoning, and the ability to apply skills and knowledge to real-world problems. Students are asked to solve problems involving the key knowledge and skills for their grade level as identified by the Common Core…

  5. Algorithmic test design using classical item parameters

    NARCIS (Netherlands)

    van der Linden, Willem J.; Adema, Jos J.

    Two optimalization models for the construction of tests with a maximal value of coefficient alpha are given. Both models have a linear form and can be solved by using a branch-and-bound algorithm. The first model assumes an item bank calibrated under the Rasch model and can be used, for instance,

  6. Item Feature Effects in Evolution Assessment

    Science.gov (United States)

    Nehm, Ross H.; Ha, Minsu

    2011-01-01

    Despite concerted efforts by science educators to understand patterns of evolutionary reasoning in science students and teachers, the vast majority of evolution education studies have failed to carefully consider or control for item feature effects in knowledge measurement. Our study explores whether robust contextualization patterns emerge within…

  7. Guideline Implementation: Prevention of Retained Surgical Items.

    Science.gov (United States)

    Fencl, Jennifer L

    2016-07-01

    A surgical item unintentionally retained in a patient after an operative or other invasive procedure is a serious, preventable medical error with the potential to cause the patient great harm. Perioperative RNs play a key role in preventing retained surgical items (RSIs). The updated AORN "Guideline for prevention of retained surgical items" provides guidance for implementing a consistent, multidisciplinary approach to RSI prevention; accounting for surgical items; preventing retention of device fragments; reconciling count discrepancies; and using adjunct technologies to supplement manual count procedures. This article focuses on key points of the guideline to help perioperative personnel provide optimal care during a procedure. Key points addressed include taking responsibility for RSI prevention as a team; minimizing distractions, noise, and interruptions during counts; using consistent counting methods; reconciling discrepancies; and participating in performance-improvement activities. Perioperative RNs should review the complete guideline for additional information and for guidance in writing and updating policies and procedures. Copyright © 2016 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  8. 47 CFR 32.7600 - Extraordinary items.

    Science.gov (United States)

    2010-10-01

    ... or Account 4110, Net current deferred nonoperating income taxes for the income tax effects (Federal... account shall also include the related income tax effect of the extraordinary items. (b) This account... Account 4070, Income taxes—accrued, shall be credited or charged for all current income tax effects...

  9. Local Development of Subject Area Item Banks.

    Science.gov (United States)

    Ward, Annie W.; Barlow, Gene

    1984-01-01

    It is feasible for school districts to develop and use subject area tests as reliable as those previously available only from commercial publishers. Three projects in local item development in a large school district are described. The first involved only Algebra 1. The second involved life science and career education at the elementary level; and…

  10. Nonlinear Analysis and Scaling Laws for Noncircular Composite Structures Subjected to Combined Loads

    Science.gov (United States)

    Hilburger, Mark W.; Rose, Cheryl A.; Starnes, James H., Jr.

    2001-01-01

    Results from an analytical study of the response of a built-up, multi-cell noncircular composite structure subjected to combined internal pressure and mechanical loads are presented. Nondimensional parameters and scaling laws based on a first-order shear-deformation plate theory are derived for this noncircular composite structure. The scaling laws are used to design sub-scale structural models for predicting the structural response of a full-scale structure representative of a portion of a blended-wing-body transport aircraft. Because of the complexity of the full-scale structure, some of the similitude conditions are relaxed for the sub-scale structural models. Results from a systematic parametric study are used to determine the effects of relaxing selected similitude conditions on the sensitivity of the effectiveness of using the sub-scale structural model response characteristics for predicting the full-scale structure response characteristics.

  11. Why item parcels are (almost) never appropriate: two wrongs do not make a right--camouflaging misspecification with item parcels in CFA models.

    Science.gov (United States)

    Marsh, Herbert W; Lüdtke, Oliver; Nagengast, Benjamin; Morin, Alexandre J S; Von Davier, Matthias

    2013-09-01

    The present investigation has a dual focus: to evaluate problematic practice in the use of item parcels and to suggest exploratory structural equation models (ESEMs) as a viable alternative to the traditional independent clusters confirmatory factor analysis (ICM-CFA) model (with no cross-loadings, subsidiary factors, or correlated uniquenesses). Typically, it is ill-advised to (a) use item parcels when ICM-CFA models do not fit the data, and (b) retain ICM-CFA models when items cross-load on multiple factors. However, the combined use of (a) and (b) is widespread and often provides such misleadingly good fit indexes that applied researchers might believe that misspecification problems are resolved--that 2 wrongs really do make a right. Taking a pragmatist perspective, in 4 studies we demonstrate with responses to the Rosenberg Self-Esteem Inventory (Rosenberg, 1965), Big Five personality factors, and simulated data that even small cross-loadings seriously distort relations among ICM-CFA constructs or even decisions on the number of factors; although obvious in item-level analyses, this is camouflaged by the use of parcels. ESEMs provide a viable alternative to ICM-CFAs and a test for the appropriateness of parcels. The use of parcels with an ICM-CFA model is most justifiable when the fit of both ICM-CFA and ESEM models is acceptable and equally good, and when substantively important interpretations are similar. However, if the ESEM model fits the data better than the ICM-CFA model, then the use of parcels with an ICM-CFA model typically is ill-advised--particularly in studies that are also interested in scale development, latent means, and measurement invariance.

  12. Solving the non-oriented three-dimensional bin packing problem with stability and load bearing constraints

    DEFF Research Database (Denmark)

    Hansen, Jesper

    2003-01-01

    The three-dimensional bin packing problem is concerned with packing a given set of rectangular items into rectangular bins. We are interested in solving real-life problems where rotations of items are allowed and the packings must be packable and stable. Load bearing of items is taken into account...

  13. Electrical load detection aparatus

    DEFF Research Database (Denmark)

    2010-01-01

    A load detection technique for a load comprising multiple frequency-dependant sub-loads comprises measuring a representation of the impedance characteristic of the load; providing stored representations of a multiplicity of impedance characteristics of the load; each one of the stored representat...

  14. Psychometric Properties of Disaster Event Reaction Items From the Crisis Counseling Individual/Family Encounter Log.

    Science.gov (United States)

    Uekawa, Kazuaki; Higgins, William Bryan; Golenbock, Samuel; Mack, Amy R; Bellamy, Nikki D

    2016-12-01

    The purpose of this article was to examine the psychometric properties of the Crisis Counseling Assistance and Training Program (CCP) data collection instrument, the Individual/Family Encounter Log (IFEL). Data collected from disaster survivors included how they reacted to events in emotional, behavioral, physical, and cognitive domains. These domains are based on conceptual categorization of event reactions and allow CCP staff to provide survivors with referrals to appropriate behavioral health support resources, if warranted. This study explored the factor structure of these survey items to determine how best to use the available information as a screen of disaster-related behavioral health indicators. Specifically, our first research question explored and confirmed the optimal factor structure of the event reaction items, and our second question examined whether the new factor structure was similar across disaster types: hurricanes, tornadoes, floods, and wildfires. Using a factor analytic technique, we tested whether our event reaction outcomes achieved consistent and reliable measurement across different disaster situations. Finally, we assessed how the new subscales were correlated with the type of risk to which CCP disaster survivors were exposed. Our analyses revealed 3 factors: (1) depressive-like, (2) anxiety-like, and (3) somatic. In addition, we found that these factors were coherent for hurricanes, floods, and wildfires, although the basic factor structure was not equivalent for tornadoes. Implications for use of the IFEL in disaster preparedness, response, and recovery are discussed. (Disaster Med Public Health Preparedness. 2016;10:822-831).

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

    Science.gov (United States)

    Scott, Neil W; Fayers, Peter M; Aaronson, Neil K; Bottomley, Andrew; de Graeff, Alexander; Groenvold, Mogens; Gundy, Chad; Koller, Michael; Petersen, Morten A; Sprangers, Mirjam A G

    2010-08-04

    Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application. A review of logistic regression DIF analyses in HRQoL was undertaken. Methodological articles from other fields and using other DIF methods were also included if considered relevant. There are many competing approaches for the conduct of DIF analyses and many criteria for determining what constitutes significant DIF. DIF in short scales, as commonly found in HRQL instruments, may be more difficult to interpret. Qualitative methods may aid interpretation of such DIF analyses. A number of methodological choices must be made when applying logistic regression for DIF analyses, and many of these affect the results. We provide recommendations based on reviewing the current evidence. Although the focus is on logistic regression, many of our results should be applicable to DIF analyses in general. There is a need for more empirical and theoretical work in this area.

  16. 41 CFR 101-30.701-2 - Item standardization code.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Item standardization code. 101-30.701-2 Section 101-30.701-2 Public Contracts and Property Management Federal Property Management....7-Item Reduction Program § 101-30.701-2 Item standardization code. Item standardization code (ISC...

  17. Empirical Appraisal of Items for Innovative Teacher Tests.

    Science.gov (United States)

    Sinclair, Norma; Pecheone, Raymond L.

    The impact of test item multidimensionality was examined as it affected fitting items on a teacher licensure test to an item response theory (IRT) model. Test item data from the 1990 study of G. W. Guiton and G. Delandshere are used. The Connecticut Elementary Certification Test (CONNECT) is a licensure examination designed to assess the subject…

  18. Latent and Manifest Monotonicity in Item Response Models.

    Science.gov (United States)

    Junker, Brian W.; Sijtsma, Klaas

    2000-01-01

    Presents results from two methods of evaluating monotonicity in item response models: regressing individual item scores on the total test score and on the "rest" score obtained by omitting the selected items from the total test score. Discusses implications for exploratory analysis of dichotomous item response data and the application of…

  19. 10 CFR 835.605 - Labeling items and containers.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Labeling items and containers. 835.605 Section 835.605... items and containers. Except as provided at § 835.606, each item or container of radioactive material... information to permit individuals handling, using, or working in the vicinity of the items or containers to...

  20. Defining Deficient Items by IRT Analysis of Calibration Data.

    Science.gov (United States)

    Krass, Iosif A.; Thomasson, Gary L.

    New items are being calibrated for the next generation of the computerized adaptive (CAT) version of the Armed Services Vocational Aptitude Battery (ASVAB) (Forms 5 and 6). The requirements that the items be "good" three-parameter logistic (3-PL) model items and typically "like" items in the previous CAT-ASVAB tests have…

  1. Differential Responses of Female Forgers to MMPI Items.

    Science.gov (United States)

    Owens, Robert G.; Harms, Laura O.

    1993-01-01

    Compared Minnesota Multiphasic Personality Inventory (MMPI) items for 128 females convicted of forgery against items for 128 females from age-matched normative sample. Thirty-three items were significant at 0.0001 level. Significant items were categorized as value system, relations with family, uncertainty, appearance of perfectionism,…

  2. The quadratic relationship between difficulty of intelligence test items and their correlations with working memory

    OpenAIRE

    Smolen, Tomasz; Chuderski, Adam

    2015-01-01

    Fluid intelligence (Gf) is a crucial cognitive ability that involves abstract reasoning in order to solve novel problems. Recent research demonstrated that Gf strongly depends on the individual effectiveness of working memory (WM). We investigated a popular claim that if the storage capacity underlay the WM-Gf correlation, then such a correlation should increase with an increasing number of items or rules (load) in a Gf test. As often no such link is observed, on that basis the storage-capaci...

  3. Item Screening in Graphical Loglinear Rasch Models

    DEFF Research Database (Denmark)

    Kreiner, Svend; Christensen, Karl Bang

    2011-01-01

    In behavioural sciences, local dependence and DIF are common, and purification procedures that eliminate items with these weaknesses often result in short scales with poor reliability. Graphical loglinear Rasch models (Kreiner & Christensen, in Statistical Methods for Quality of Life Studies, ed....... by M. Mesbah, F.C. Cole & M.T. Lee, Kluwer Academic, pp. 187–203, 2002) where uniform DIF and uniform local dependence are permitted solve this dilemma by modelling the local dependence and DIF. Identifying loglinear Rasch models by a stepwise model search is often very time consuming, since...... the initial item analysis may disclose a great deal of spurious and misleading evidence of DIF and local dependence that has to disposed of during the modelling procedure. Like graphical models, graphical loglinear Rasch models possess Markov properties that are useful during the statistical analysis...

  4. Distribution load estimation (DLE)

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Lehtonen, M. [VTT Energy, Espoo (Finland)

    1998-08-01

    The load research has produced customer class load models to convert the customers` annual energy consumption to hourly load values. The reliability of load models applied from a nation-wide sample is limited in any specific network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to find improvements to the load models or, in general, improvements to the load estimates. In Distribution Load Estimation (DLE) the measurements from the network are utilized to improve the customer class load models. The results of DLE will be new load models that better correspond to the loading of the distribution network but are still close to the original load models obtained by load research. The principal data flow of DLE is presented

  5. Examining the Role of Predictor Variables of Mental Health and Personality Subscales in Internet Addiction of Students in Medical and non-Medical Universities of Sanandaj in 2014

    Directory of Open Access Journals (Sweden)

    Afshin Salahian

    2015-12-01

    Full Text Available Background and objective: According to the high and increasing prevalence of internet addiction, and the fact that little research has been done on the predictors of internet addiction in Iran, the purpose of this study was to examine the role of predictor variables of mental health and personality subscales in internet addiction of students in medical and non-medical universities of Sanandaj in 2014. Methods: The Method of this research was correlation and the statistical population were all of medical and non-medical students of Sanandaj Universities in 2014. In this study, 250 students (125 female and 125 male, were randomly selected, and completed the checklist of mental health symptoms, NEO personality questionnaire, and internet addiction questionnaire. Data were analyzed using Pearson Correlation, stepwise regression, and T test by SPSS software version 20. Results: The results indicated that obsession-compulsion, openness, consciousness, aggression and somatization subscales had predictor roles in internet addiction, and totally 51 percent of variances predicted the internet addiction (F=29.97; P=0.001. Conclusion: The internet addiction of university students is dependent upon their mental health and personality, and one can predict the internet addiction of students via subscales of mental health and personality.

  6. In competition for the attentional template: can multiple items within visual working memory guide attention?

    Science.gov (United States)

    van Moorselaar, Dirk; Theeuwes, Jan; Olivers, Christian N L

    2014-08-01

    Recent studies have revealed that the deployment of attention can be biased by the content of visual working memory (VWM), but that stored memories do not always interact with attention. This has led to a model which proposes a division within VWM between a single active template that interacts with perception and multiple accessory representations that do not. The present study was designed to study whether multiple memory representations are able to bias attention. Participants performed a visual search task while maintaining a variable number of colors in VWM. Consistent with earlier findings, we observed increased attentional capture by memory related distractors when VWM was filled with a single item. However, memory related capture was no longer present for memory loads beyond a single item. The absence of memory related capture at higher VWM loads was independent of individual VWM capacity, nor was it attributable to weaker encoding, forgetting, or reduced precision of memory representations. When analyses were limited to those trials in which participants had a relatively precise memory, there was still no sign of attentional guidance at higher loads. However, when observers were cued toward a specific memory item after encoding, interference with search returned. These results are consistent with a distinction within VWM between representations that interact with perception and those that do not, and show that only a single VWM representation at a time can interact with visual attention.

  7. 17 CFR 260.7a-16 - Inclusion of items, differentiation between items and answers, omission of instructions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Inclusion of items, differentiation between items and answers, omission of instructions. 260.7a-16 Section 260.7a-16 Commodity and... INDENTURE ACT OF 1939 Formal Requirements § 260.7a-16 Inclusion of items, differentiation between items and...

  8. Distribution load estimation - DLE

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland)

    1996-12-31

    The load research project has produced statistical information in the form of load models to convert the figures of annual energy consumption to hourly load values. The reliability of load models is limited to a certain network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to make improvements in the load models. Distribution load estimation (DLE) is the method developed here to improve load estimates from the load models. The method is also quite cheap to apply as it utilises information that is already available in SCADA systems

  9. 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.

  10. Developing Items to Measure Theory of Planned Behavior Constructs for Opioid Administration for Children: Pilot Testing.

    Science.gov (United States)

    Vincent, Catherine; Riley, Barth B; Wilkie, Diana J

    2015-12-01

    The Theory of Planned Behavior (TpB) is useful to direct nursing research aimed at behavior change. As proposed in the TpB, individuals' attitudes, perceived norms, and perceived behavior control predict their intentions to perform a behavior and subsequently predict their actual performance of the behavior. Our purpose was to apply Fishbein and Ajzen's guidelines to begin development of a valid and reliable instrument for pediatric nurses' attitudes, perceived norms, perceived behavior control, and intentions to administer PRN opioid analgesics when hospitalized children self-report moderate to severe pain. Following Fishbein and Ajzen's directions, we were able to define the behavior of interest and specify the research population, formulate items for direct measures, elicit salient beliefs shared by our target population and formulate items for indirect measures, and prepare and test our questionnaire. For the pilot testing of internal consistency of measurement items, Cronbach alphas were between 0.60 and 0.90 for all constructs. Test-retest reliability correlations ranged from 0.63 to 0.90. Following Fishbein and Ajzen's guidelines was a feasible and organized approach for instrument development. In these early stages, we demonstrated good reliability for most subscales, showing promise for the instrument and its use in pain management research. Better understanding of the TpB constructs will facilitate the development of interventions targeted toward nurses' attitudes, perceived norms, and/or perceived behavior control to ultimately improve their pain behaviors toward reducing pain for vulnerable children. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  11. Prolonged-release fampridine treatment improved subject-reported impact of multiple sclerosis: Item-level analysis of the MSIS-29.

    Science.gov (United States)

    Gasperini, Claudio; Hupperts, Raymond; Lycke, Jan; Short, Christine; McNeill, Manjit; Zhong, John; Mehta, Lahar R

    2016-11-15

    Prolonged-release (PR) fampridine is approved to treat walking impairment in persons with multiple sclerosis (MS); however, treatment benefits may extend beyond walking. MOBILE was a phase 2, 24-week, double-blind, placebo-controlled exploratory study to assess the impact of 10mg PR-fampridine twice daily versus placebo on several subject-assessed measures. This analysis evaluated the physical and psychological health outcomes of subjects with progressing or relapsing MS from individual items of the Multiple Sclerosis Impact Scale (MSIS-29). PR-fampridine treatment (n=68) resulted in greater improvements from baseline in the MSIS-29 physical (PHYS) and psychological (PSYCH) impact subscales, with differences of 89% and 148% in mean score reduction from baseline (n=64) at week 24 versus placebo, respectively. MSIS-29 item analysis showed that a higher percentage of PR-fampridine subjects had mean improvements in 16/20 PHYS and 6/9 PSYCH items versus placebo after 24weeks. Post hoc analysis of the 12-item Multiple Sclerosis Walking Scale (MSWS-12) improver population (≥8-point mean improvement) demonstrated differences in mean reductions from baseline of 97% and 111% in PR-fampridine MSIS-29 PHYS and PSYCH subscales versus the overall placebo group over 24weeks. A higher percentage of MSWS-12 improvers treated with PR-fampridine showed mean improvements in 20/20 PHYS and 8/9 PSYCH items versus placebo at 24weeks. In conclusion, PR-fampridine resulted in physical and psychological benefits versus placebo, sustained over 24weeks. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Assessment of quality of life in patients receiving palliative care: comparison of measurement tools and single item on subjective well-being.

    Science.gov (United States)

    Stiel, Stephanie; Psych, Dipl; Kues, Katharina; Krumm, Norbert; Radbruch, Lukas; Elsner, Frank

    2011-05-01

    Many quality-of-life assessment tools are not feasible in palliative care settings because of the severe impairment of the physical, cognitive, and psychological status of patients. This study investigated whether comprehensive instruments can be replaced by a single item concerning the well-being of patients. From April to December 2008 patients receiving palliative care in three different settings (palliative care unit, inpatient unit of the department of radiotherapy, inpatient hospice) were asked to answer the assessment tools Functional Assessment of Chronic Illness Treatment (FACIT-G), European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30), Schedule for the Evaluation of the Individual Quality of Life (SEIQoL), and the Minimal Documentation System (MIDOS) including a single item on well-being. Correlations of sum and specific domain scores were used for correlational analysis. Datasets of 72 patients were collected. The MIDOS single item on well-being correlated significantly with the QoL indexes of the EORTC (Spearman rank correlation r = -0.563) and FACIT-G (0.527). SEIQoL had low to moderate correlations with the other assessment tools. Subscales on physical functioning from the FACIT-G (r = 0.583) and the EORTC-QLQ-C30 (r = 0.385) had the highest correlation with the single item on well-being. Well-being correlated higher with nonphysical subscales of the QoL instruments for patients in the palliative care unit than in the radiotherapy department. The single item is unable to completely replace comprehensive questionnaires, but it is useful to initiate communication on QoL and can be recommended as a substitute for physical-functional aspects of QoL assessment in the palliative care setting.

  13. Pengendalian Persediaan Primary Items dalam Logistik Konstruksi

    Directory of Open Access Journals (Sweden)

    Lady Lisya

    2016-09-01

    Full Text Available Construction logistics are activities that consist of ordering, storage and transportation of materials of construction projects. Storage material is logistics activity that ensure the availability of materials in project site. Generally, material storage activities have been conducted at the project site. Logistics construction is aimed to support the project activities that the completion schedule has been set. Construction logistics issues is determining the schedule of ordering materials so that the project can be implemented on schedule. The purpose of research is to determine the optimum ordering period for the primary items on the main building structure construction and designing inventory control cards as a mechanism for monitoring procurement of materials. This research has been obtained optimal ordering period for the primary items of main building structure with elements of the work using Fixed Period Requirement method. Inventories were already meet the material requirement of each period. Material management has been conducted based grouping approach as many as 31 groups. In addition, this research has proposed the inventory control cards as an instrument for material procurement monitoring. The implications of inventory control cards are coordinate contracting parties with vendors to plan the replenishment  of materials to meet the work schedule. Further research can be developed with other aspects such as integrated material order system between contractors and vendors to consider the safety stock. In addition, the information system for planning material is an important consideration for construction projects with large scale so that the companies can plan primary items inventory and other materials in the projects completion more easily, quickly and accurately.

  14. Fuzzy stochastic inventory model for deteriorating item

    Directory of Open Access Journals (Sweden)

    Waliv Rahul H.

    2017-01-01

    Full Text Available A multi item profit maximization inventory model is developed in fuzzy stochastic environment. Demand is taken as Stock dependent demand. Available storage space is assumed to be imprecise and vague in nature. Impreciseness has been expressed by linear membership function. Purchasing cost and investment constraint are considered to be random and their randomness is expressed by normal distribution. The model has been formulated as a fuzzy stochastic programming problem and reduced to corresponding equivalent fuzzy linear programming problem. The model has been solved by using fuzzy linear programming technique and illustrated numerically.

  15. Maternal Antenatal Attachment Scale (MAAS): adaptation to Spanish and proposal for a brief version of 12 items.

    Science.gov (United States)

    Navarro-Aresti, Lucía; Iraurgi, Ioseba; Iriarte, Leire; Martínez-Pampliega, Ana

    2016-02-01

    The psychometric properties of the adapted Spanish version of the Maternal Antenatal Attachment Scale were examined. The main goal was to investigate the reliability and construct validity of the conceptual structure of Condon's proposal. Five hundred twenty-five pregnant women, attending maternal education classes in Bizkaia (Spain), answered the translated and back-translated version of the Maternal Antenatal Attachment Scale. This scale comprises 19 items with five answer choices divided into two subscales: quality of attachment and intensity of attachment. Participants also answered a questionnaire about the reproductive history that was developed ad hoc for the present study. The Spanish adaptation of the Maternal Antenatal Attachment Scale final version comprises 12 items: seven items have been removed due to their inadequate psychometric properties. Internal consistency of the inventory is moderate-high (.73) and it ranges from .68 (intensity of attachment) to .75 (quality of attachment) for the dimensions. Three alternative structural models were proven using a confirmatory factor analysis. Lastly, the two-related-factor model was chosen, as it obtained suitable fit indexes (χ (2) = 102.28; p Attachment Scale can be proposed as a suitable instrument for the purpose of measuring antenatal attachment. The study of antenatal attachment helps to detect possible difficulties for the mother in establishing an affective relationship with the foetus. This may affect the foetus growth, delivery and the future mother-child relationship.

  16. Self-Harm Subscale of the Schedule for Nonadaptive and Adaptive Personality (SNAP): Predicting Suicide Attempts Over 8 Years of Follow-Up

    Science.gov (United States)

    Yen, Shirley; Shea, M. Tracie; Walsh, Zach; Edelen, Maria O.; Hopwood, Christopher J.; Markowitz, John C.; Ansell, Emily B.; Morey, Leslie C.; Grilo, Carlos M.; Sanislow, Charles A.; Skodol, Andrew E.; Gunderson, John G.; Zanarini, Mary C.; McGlashan, Thomas H.

    2013-01-01

    Objective We examined the predictive power of the self-harm subscale of the Schedule for Nonadaptive and Adaptive Personality (SNAP) to identify suicide attempters in the Collaborative Longitudinal Study of Personality Disorders (CLPS). Method The SNAP, a self-report personality inventory, was administered to 733 CLPS participants at baseline, of whom 701 (96%) had at least 6 months of follow-up data. Cox proportional hazards regression analyses were performed to examine the SNAP–self-harm subscale (SNAP-SH) in predicting the 129 suicide attempters over 8 years of follow-up. Possible moderators of prediction were examined, including borderline personality disorder, major depressive disorder (MDD), and substance use disorder. We also compared baseline administration of the SNAP-SH to subsequent administrations more proximal to the suicide attempt, and to a higher-order SNAP-negative temperament (SNAP-NT) subscale. Receiver operating characteristic analyses were conducted using suicide attempts (n = 58) over the first year of follow-up to provide reference points for sensitivity and specificity. Results The SNAP-SH demonstrated good predictive power for suicide attempts (hazard ratio = 1.28, P < .001) and appeared relatively consistent across borderline personality disorder, MDD, and substance use disorder diagnoses. Using more proximal scores did not increase predictive power. The SNAP-SH compared favorably to the predictive power of the higher-order SNAP-NT. Receiver operating characteristic analyses indicate several cutoff scores on the SNAP-SH that yield moderate to high sensitivity and specificity for predicting suicide attempts over the first year of follow-up. Conclusions The SNAP-SH may be a useful screening instrument for risk of suicide attempts in nonpsychotic psychiatric patients. PMID:21294991

  17. Evaluation of Neuropsychiatric Function in Phenylketonuria: Psychometric Properties of the ADHD Rating Scale-IV and Adult ADHD Self-Report Scale Inattention Subscale in Phenylketonuria.

    Science.gov (United States)

    Wyrwich, Kathleen W; Auguste, Priscilla; Yu, Ren; Zhang, Charlie; Dewees, Benjamin; Winslow, Barbara; Yu, Shui; Merilainen, Markus; Prasad, Suyash

    2015-06-01

    Previous qualitative research among adults and parents of children with phenylketonuria (PKU) has identified inattention as an important psychiatric aspect of this condition. The parent-reported ADHD Rating Scale-IV (ADHD RS-IV) and the Adult ADHD Self-Report Scale (ASRS) have been validated for measuring inattention symptoms in persons with attention-deficit/hyperactivity disorder (ADHD); however, their psychometric attributes for measuring PKU-related inattention have not been established. The primary objective of this investigation was to demonstrate the reliability, validity, and responsiveness of the ADHD RS-IV and ASRS inattention symptoms subscales in a randomized controlled trial of patients with PKU aged 8 years or older. A post hoc analysis investigated the psychometric properties (Rasch model fit, reliability, construct validity, and responsiveness) of the ADHD RS-IV and ASRS inattention subscales using data from a phase 3b, double-blind, placebo-controlled clinical trial in those with PKU aged 8 years or older. The Rasch results revealed good model fit, and reliability analyses revealed strong internal consistency reliability (α ≥ 0.87) and reproducibility (intraclass correlation coefficient ≥ 0.87) for both measures. Both inattention measures demonstrated the ability to discriminate between known groups (P < 0.001) created by the Clinical Global Impression-Severity scale. Correlations between the ADHD RS-IV and the ASRS with the Clinical Global Impression-Severity scale and the age-appropriate Behavior Rating Inventory of Executive Function Working Memory subscale were consistently moderate to strong (r ≥ 0.56). Similarly, results of the change score correlations were of moderate magnitude (r ≥ 0.43) for both measures when compared with changes over time in Behavior Rating Inventory of Executive Function Working Memory subscales. These findings of reliability, validity, and responsiveness of both the ADHD RS-IV and the ASRS inattention scales

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

    Science.gov (United States)

    Scott, Neil W; Fayers, Peter M; Aaronson, Neil K; Bottomley, Andrew; de Graeff, Alexander; Groenvold, Mogens; Gundy, Chad; Koller, Michael; Petersen, Morten A; Sprangers, Mirjam A G

    2009-04-01

    Differential item functioning (DIF) analyses can be used to explore translation, cultural, gender or other differences in the performance of quality of life (QoL) instruments. These analyses are commonly performed using "baseline" or pretreatment data. We previously reported DIF analyses to examine the pattern of item responses for translations of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 QoL instrument, using only data collected prior to cancer treatment. We now compare the consistency of these results with similar analyses of on-treatment and off-treatment assessments and explore whether item relationships differ from those at baseline. Logistic regression DIF analyses were used to examine the translation of each item in each multi-item scale at the three time points, after controlling for the overall scale score and other covariates. The consistency of results at the three time points was explored. For most EORTC QLQ-C30 subscales, the DIF results were very consistent across the three time points. Results for the Nausea and Vomiting scale varied the most across assessments. The results indicated that DIF analyses were stable across each time point and that the same DIF effects were usually found regardless of the treatment status of the respondent.

  19. Development of the PROMIS Social Motivations for Smoking item banks.

    Science.gov (United States)

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

    2014-09-01

    Smoking behavior is influenced by social motivations such as the expected social benefits of smoking and the social cues that induce craving. This paper describes development of the PROMIS Social Motivations for Smoking item banks, which will serve to standardize assessment of these social motivations among daily and nondaily smokers. Daily (N = 4,201) and nondaily (N =1,183) smokers completed an online survey. Item factor analyses, item response theory analyses, and differential item functioning analyses were conducted to identify a unidimensional set of items for each group. Short forms (SFs) and computer adaptive tests (CATs) were evaluated as tools for more efficiently assessing this construct. A total of 15 items were included in the item banks (9 items common to daily and nondaily smokers, 3 unique to daily, 3 unique to nondaily). Scores based on full item banks are highly reliable (reliability = 0.90-0.91). Additionally, the item banks are strongly unidimensional and perform similarly across gender, age, and race/ethnicity groups. A fixed SF for use with both daily and nondaily smokers consists of 4 items (reliability = 0.80). Results from simulated CATs showed that, on average, fewer than 5 items are needed to assess this construct with adequate precision using the item banks. A new set of items has been identified for assessing the social motivations for smoking in a reliable, standardized manner for daily and nondaily smokers. In addition to using the full item banks, efficient assessment can be achieved by using SFs, employing CATs, or selecting 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.

  20. Development and Design of a Dynamic Multimedia Item Generation Mechanism

    Science.gov (United States)

    Weng, Ting-Sheng

    2012-01-01

    This research applies multimedia technology to design a dynamic item generation method that can adaptively adjust the difficulty level of items according to the level of the testee. The method is based on interactive testing software developed by Flash Actionscript, and provides a testing solution for users by automatically distributing items of…

  1. DIF Detection and Effect Size Measures for Polytomously Scored Items

    Science.gov (United States)

    Kim, Seock-Ho; Cohen, Allan S.; Alagoz, Cigdem; Kim, Sukwoo

    2007-01-01

    Data from a large-scale performance assessment (N = 105,731) were analyzed with five differential item functioning (DIF) detection methods for polytomous items to examine the congruence among the DIF detection methods. Two different versions of the item response theory (IRT) model-based likelihood ratio test, the logistic regression likelihood…

  2. Comparative Racial Analysis of Enlisted Advancement Exams: Item Differentiation

    Science.gov (United States)

    1977-01-01

    homogeneity may be the types of items that besc contribute to predicting job-relevant performance by an external criterion. Thus, until externa ...the item itself (Nunnally, 1967). (Obviously, the size of this artifact will vary inversely with the number of items in the test/section.) Also, if a

  3. The 10-Item Substance Use Disorder Outcome Scale: Psychometric evaluation.

    Science.gov (United States)

    Westermeyer, Joseph; Yoon, Gihyun; Thuras, Paul; Batres-Y-Carr, Tegan; McNairy, Scott; Swanson, Heather

    2017-01-01

    The current study describes the psychometric properties of a scale (entitled "Substance Use Disorder Outcome Scale-10 items" or 10-Item Substance Use Disorder Outcome Scale) designed for longitudinal studies. Sixteen male veterans attending a substance use disorder recovery clinic were studied over a 2-year period. The attending nurse and physician conducted four, 10-Item Substance Use Disorder Outcome Scale scale ratings, each encompassing a 6-month period, for each participant. Analyses involved scale descriptive results, Cronbach alpha scores, effects of deleting the item on Cronbach alpha scores for the remaining items, and item-to-scale correlations across the four periods, plus three exploratory studies. Scale scores showed skewness p ≤ 1.0 and Cronbach alphas of 0.89 to 0.93. Six of 10 items correlated with total scale scores at 3 or 4 rating periods at p ≤ 0.005. Two items showed p ≤ 0.005 correlations only in the first two periods, and two items showed p ≤ 0.005 correlations only in the last two periods. Exploratory analyses revealed some item convergence over time plus non-significant associations with long-standing demographic and clinical variables. Desirable 10-Item Substance Use Disorder Outcome Scale psychometric properties included normal distribution, excellent Cronbach alphas, and high item-to-score correlations, all of which persisted over time.

  4. Optimal Test Design with Rule-Based Item Generation

    Science.gov (United States)

    Geerlings, Hanneke; van der Linden, Wim J.; Glas, Cees A. W.

    2013-01-01

    Optimal test-design methods are applied to rule-based item generation. Three different cases of automated test design are presented: (a) test assembly from a pool of pregenerated, calibrated items; (b) test generation on the fly from a pool of calibrated item families; and (c) test generation on the fly directly from calibrated features defining…

  5. Optimal test design with rule-based item generation

    NARCIS (Netherlands)

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

    2013-01-01

    Optimal test-design methods are applied to rule-based item generation. Three different cases of automated test design are presented: (a) test assembly from a pool of pregenerated, calibrated items; (b) test generation on the fly from a pool of calibrated item families; and (c) test generation on the

  6. A Mixture Rasch Model with Item Response Time Components

    Science.gov (United States)

    Meyer, J. Patrick

    2010-01-01

    An examinee faced with a test item will engage in solution behavior or rapid-guessing behavior. These qualitatively different test-taking behaviors bias parameter estimates for item response models that do not control for such behavior. A mixture Rasch model with item response time components was proposed and evaluated through application to real…

  7. Guide to good practices for the development of test items

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    While the methodology used in developing test items can vary significantly, to ensure quality examinations, test items should be developed systematically. Test design and development is discussed in the DOE Guide to Good Practices for Design, Development, and Implementation of Examinations. This guide is intended to be a supplement by providing more detailed guidance on the development of specific test items. This guide addresses the development of written examination test items primarily. However, many of the concepts also apply to oral examinations, both in the classroom and on the job. This guide is intended to be used as guidance for the classroom and laboratory instructor or curriculum developer responsible for the construction of individual test items. This document focuses on written test items, but includes information relative to open-reference (open book) examination test items, as well. These test items have been categorized as short-answer, multiple-choice, or essay. Each test item format is described, examples are provided, and a procedure for development is included. The appendices provide examples for writing test items, a test item development form, and examples of various test item formats.

  8. 31 CFR 50.14 - Separate line item.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Separate line item. 50.14 Section 50... PROGRAM Disclosures as Conditions for Federal Payment § 50.14 Separate line item. An insurer is deemed to be in compliance with the requirement of providing disclosure on a “separate line item in the policy...

  9. Mokken Scale Analysis for Dichotomous Items Using Marginal Models

    Science.gov (United States)

    van der Ark, L. Andries; Croon, Marcel A.; Sijtsma, Klaas

    2008-01-01

    Scalability coefficients play an important role in Mokken scale analysis. For a set of items, scalability coefficients have been defined for each pair of items, for each individual item, and for the entire scale. Hypothesis testing with respect to these scalability coefficients has not been fully developed. This study introduces marginal modelling…

  10. DIF Trees: Using Classification Trees to Detect Differential Item Functioning

    Science.gov (United States)

    Vaughn, Brandon K.; Wang, Qiu

    2010-01-01

    A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…

  11. Graphical modeling for item difficulty in medical faculty exams

    African Journals Online (AJOL)

    Conclusion: The control charts have the advantage for classifying items as acceptable or unacceptable based on item difficulty criteria. Key words: Item difficulty, quality control, statistical process control, variable control charts. Date of Acceptance: 26-Jun-2015. Address for correspondence: Dr. L Tomak,. Department of ...

  12. ASCAL: A Microcomputer Program for Estimating Logistic IRT Item Parameters.

    Science.gov (United States)

    Vale, C. David; Gialluca, Kathleen A.

    ASCAL is a microcomputer-based program for calibrating items according to the three-parameter logistic model of item response theory. It uses a modified multivariate Newton-Raphson procedure for estimating item parameters. This study evaluated this procedure using Monte Carlo Simulation Techniques. The current version of ASCAL was then compared to…

  13. Higher-Order Item Response Models for Hierarchical Latent Traits

    Science.gov (United States)

    Huang, Hung-Yu; Wang, Wen-Chung; Chen, Po-Hsi; Su, Chi-Ming

    2013-01-01

    Many latent traits in the human sciences have a hierarchical structure. This study aimed to develop a new class of higher order item response theory models for hierarchical latent traits that are flexible in accommodating both dichotomous and polytomous items, to estimate both item and person parameters jointly, to allow users to specify…

  14. A simple and fast item selection procedure for adaptive testing

    NARCIS (Netherlands)

    Veerkamp, W.J.J.; Veerkamp, Wim J.J.; Berger, Martijn; Berger, Martijn P.F.

    1994-01-01

    Items with the highest discrimination parameter values in a logistic item response theory (IRT) model do not necessarily give maximum information. This paper shows which discrimination parameter values (as a function of the guessing parameter and the distance between person ability and item

  15. The Development of Practical Item Analysis Program for Indonesian Teachers

    Science.gov (United States)

    Muhson, Ali; Lestari, Barkah; Supriyanto; Baroroh, Kiromim

    2017-01-01

    Item analysis has essential roles in the learning assessment. The item analysis program is designed to measure student achievement and instructional effectiveness. This study was aimed to develop item-analysis program and verify its feasibility. This study uses a Research and Development (R & D) model. The procedure includes designing and…

  16. 7 CFR 65.220 - Processed food item.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Processed food item. 65.220 Section 65.220 Agriculture..., PEANUTS, AND GINSENG General Provisions Definitions § 65.220 Processed food item. Processed food item... other covered commodity or other substantive food component (e.g., chocolate, breading, tomato sauce...

  17. Multistage Computerized Adaptive Testing with Uniform Item Exposure

    Science.gov (United States)

    Edwards, Michael C.; Flora, David B.; Thissen, David

    2012-01-01

    This article describes a computerized adaptive test (CAT) based on the uniform item exposure multi-form structure (uMFS). The uMFS is a specialization of the multi-form structure (MFS) idea described by Armstrong, Jones, Berliner, and Pashley (1998). In an MFS CAT, the examinee first responds to a small fixed block of items. The items comprising…

  18. 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...

  19. Verification of Differential Item Functioning (DIF) Status of West ...

    African Journals Online (AJOL)

    This study investigated test item bias and Differential Item Functioning (DIF) of West African Senior School Certificate Examination (WASSCE) in chemistry. The major objective was to examine how WASSCE items in chemistry function differentially with respect to gender and location. In Aba education zone of Abia, ...

  20. Examining differential item functioning due to difficulty and alternative attractiveness

    NARCIS (Netherlands)

    Westers, Paul; Kelderman, Henk

    1992-01-01

    A method for analyzing test item responses is proposed to examine differential item functioning (DIF) in multiple-choice items through a combination of the usual notion of DIF, for correct/incorrect responses and information about DIF contained in each of the alternatives. The proposed method uses

  1. A scale purification procedure for evaluation of differential item functioning

    NARCIS (Netherlands)

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

    2014-01-01

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

  2. 48 CFR 1852.246-73 - Human space flight item.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Human space flight item... 1852.246-73 Human space flight item. As prescribed in 1845.370(b), insert the following clause: Human Space Flight Item (MAR 1997) The Contractor shall include the following statement in all subcontracts...

  3. 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.

  4. A Comparison of Methods for Nonparametric Estimation of Item Characteristic Curves for Binary Items

    Science.gov (United States)

    Lee, Young-Sun

    2007-01-01

    This study compares the performance of three nonparametric item characteristic curve (ICC) estimation procedures: isotonic regression, smoothed isotonic regression, and kernel smoothing. Smoothed isotonic regression, employed along with an appropriate kernel function, provides better estimates and also satisfies the assumption of strict…

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

    Science.gov (United States)

    Berger, Moritz; Tutz, Gerhard

    2016-01-01

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

  6. Item Discrimination and Type I Error in the Detection of Differential Item Functioning

    Science.gov (United States)

    Li, Yanju; Brooks, Gordon P.; Johanson, George A.

    2012-01-01

    In 2009, DeMars stated that when impact exists there will be Type I error inflation, especially with larger sample sizes and larger discrimination parameters for items. One purpose of this study is to present the patterns of Type I error rates using Mantel-Haenszel (MH) and logistic regression (LR) procedures when the mean ability between the…

  7. The Effect of Differential Item Functioning in Anchor Items on Population Invariance of Equating

    Science.gov (United States)

    Huggins, Anne Corinne

    2014-01-01

    Invariant relationships in the internal mechanisms of estimating achievement scores on educational tests serve as the basis for concluding that a particular test is fair with respect to statistical bias concerns. Equating invariance and differential item functioning are both concerned with invariant relationships yet are treated separately in the…

  8. Analysis of Item Response and Differential Item Functioning of Alcohol Expectancies in Middle School Youths

    Science.gov (United States)

    McCarthy, Denis M.; Pedersen, Sarah L.; D'Amico, Elizabeth J.

    2009-01-01

    Drinking behavior in preadolescence is a significant predictor of both short- and long-term negative consequences. This study examined the psychometric properties of 1 known risk factor for drinking in this age group, alcohol expectancies, within an item response theory framework. In a sample of middle school youths (N = 1,273), the authors tested…

  9. Factor- and Item-Level Analyses of the 38-Item Activities Scale for Kids-Performance

    Science.gov (United States)

    Bagley, Anita M.; Gorton, George E.; Bjornson, Kristie; Bevans, Katherine; Stout, Jean L.; Narayanan, Unni; Tucker, Carole A.

    2011-01-01

    Aim: Children and adolescents highly value their ability to participate in relevant daily life and recreational activities. The Activities Scale for Kids-performance (ASKp) instrument measures the frequency of performance of 30 common childhood activities, and has been shown to be valid and reliable. A revised and expanded 38-item ASKp (ASKp38)…

  10. Detecting a Gender-Related Differential Item Functioning Using Transformed Item Difficulty

    Science.gov (United States)

    Abedalaziz, Nabeel; Leng, Chin Hai; Alahmadi, Ahlam

    2014-01-01

    The purpose of the study was to examine gender differences in performance on multiple-choice mathematical ability test, administered within the context of high school graduation test that was designed to match eleventh grade curriculum. The transformed item difficulty (TID) was used to detect a gender related DIF. A random sample of 1400 eleventh…

  11. Dependability of technical items: Problems of standardization

    Science.gov (United States)

    Fedotova, G. A.; Voropai, N. I.; Kovalev, G. F.

    2016-12-01

    This paper is concerned with problems blown up in the development of a new version of the Interstate Standard GOST 27.002 "Industrial product dependability. Terms and definitions". This Standard covers a wide range of technical items and is used in numerous regulations, specifications, standard and technical documentation. A currently available State Standard GOST 27.002-89 was introduced in 1990. Its development involved a participation of scientists and experts from different technical areas, its draft was debated in different audiences and constantly refined, so it was a high quality document. However, after 25 years of its application it's become necessary to develop a new version of the Standard that would reflect the current understanding of industrial dependability, accounting for the changes taking place in Russia in the production, management and development of various technical systems and facilities. The development of a new version of the Standard makes it possible to generalize on a terminological level the knowledge and experience in the area of reliability of technical items, accumulated over a quarter of the century in different industries and reliability research schools, to account for domestic and foreign experience of standardization. Working on the new version of the Standard, we have faced a number of issues and problems on harmonization with the International Standard IEC 60500-192, caused first of all by different approaches to the use of terms and differences in the mentalities of experts from different countries. The paper focuses on the problems related to the chapter "Maintenance, restoration and repair", which caused difficulties for the developers to harmonize term definitions both with experts and the International Standard, which is mainly related to differences between the Russian concept and practice of maintenance and repair and foreign ones.

  12. A Nonlinear Dynamic Subscale Model for Partially Resolved Numerical Simulation (PRNS)/Very Large Eddy Simulation (VLES) of Internal Non-Reacting Flows

    Science.gov (United States)

    Shih, Tsan-Hsing; Liu, nan-Suey

    2010-01-01

    A brief introduction of the temporal filter based partially resolved numerical simulation/very large eddy simulation approach (PRNS/VLES) and its distinct features are presented. A nonlinear dynamic subscale model and its advantages over the linear subscale eddy viscosity model are described. In addition, a guideline for conducting a PRNS/VLES simulation is provided. Results are presented for three turbulent internal flows. The first one is the turbulent pipe flow at low and high Reynolds numbers to illustrate the basic features of PRNS/VLES; the second one is the swirling turbulent flow in a LM6000 single injector to further demonstrate the differences in the calculated flow fields resulting from the nonlinear model versus the pure eddy viscosity model; the third one is a more complex turbulent flow generated in a single-element lean direct injection (LDI) combustor, the calculated result has demonstrated that the current PRNS/VLES approach is capable of capturing the dynamically important, unsteady turbulent structures while using a relatively coarse grid.

  13. Association between somatization subscale score and serotonin transporter availability in healthy volunteers--a single photon emission computed tomography study with [¹²³I] ADAM.

    Science.gov (United States)

    Chou, Ming Hui; Chen, Kao Chin; Yeh, Tzung Lieh; Lee, I Hui; Yao, Wei Jen; Chen, Po See; Chang, Kang-Wei; Liao, Mei-Hsiu; Yang, Yen Kuang

    2012-02-01

    Serotonin is one of the key neuromodulators involved in fundamental cerebral functions and behaviors. Previous study has demonstrated that somatization symptoms are probably associated with central serotonergic circuits, which are implicated in anxiety and nociception regulation. This study aims to examine the correlation between somatization subscale score and serotonin transporter (SERT) availability in healthy volunteers. Sixty-four healthy participants, 26 males and 38 females, were enrolled from the community and were administered the single somatization subscale of the Chinese symptom checklist 90 revised (SCL90-R). Single photon emission computed tomography with [(123)I] 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine was also performed to examine SERT availability. The somatization scores were negatively correlated with SERT availability (Spearman's ρ = -0.35, p = 0.005), particularly in males (Spearman's ρ = -0.54, p = 0.004). This result reconfirmed the correlation between central serotonergic activity and the intensity of somatization symptoms, even in healthy participants. However, a gender difference exists in this correlation.

  14. Observed Agreement Problems between Sub-Scales and Summary Components of the SF-36 Version 2 - An Alternative Scoring Method Can Correct the Problem

    Science.gov (United States)

    Tucker, Graeme; Adams, Robert; Wilson, David

    2013-01-01

    Purpose A number of previous studies have shown inconsistencies between sub-scale scores and component summary scores using traditional scoring methods of the SF-36 version 1. This study addresses the issue in Version 2 and asks if the previous problems of disagreement between the eight SF-36 Version 1 sub-scale scores and the Physical and Mental Component Summary persist in version 2. A second study objective is to review the recommended scoring methods for the creation of factor scoring weights and the effect on producing summary scale scores Methods The 2004 South Australian Health Omnibus Survey dataset was used for the production of coefficients. There were 3,014 observations with full data for the SF-36. Data were analysed in LISREL V8.71. Confirmatory factor analysis models were fit to the data producing diagonally weighted least squares estimates. Scoring coefficients were validated on an independent dataset, the 2008 South Australian Health Omnibus Survey. Results Problems of agreement were observed with the recommended orthogonal scoring methods which were corrected using confirmatory factor analysis. Conclusions Confirmatory factor analysis is the preferred method to analyse SF-36 data, allowing for the correlation between physical and mental health. PMID:23593428

  15. Clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale change in relation to goal attainment in patients on cholinesterase inhibitors.

    Science.gov (United States)

    Rockwood, Kenneth; Howlett, Susan E; Hoffman, Deborah; Schindler, Rachel; Mitnitski, Arnold

    2017-10-01

    The clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) subscale change is disputed. We compared 2- to 4-point ADAS-Cog changes with changes in Goal Attainment Scaling (GAS) and everyday function across initial ADAS-Cog scores and treatment responses. This exploratory analysis evaluated mild-moderate Alzheimer's disease patients treated with donepezil (12 months) or galantamine (8 months). Clinical meaningfulness was defined as concomitant ADAS-Cog and GAS changes of ±3 points and/or functional improvement. Patients with ≥3-point ADAS-Cog improvement significantly improved on GAS but not on standard tests of everyday function. ADAS-Cog "no change" (≤±3 points) was seen with mean GAS improvement. Initial ADAS-Cog improvement made endpoint improvement (ADAS-Cog 3 points and GAS 1 point) more likely (odds ratio = 6.9; 95% confidence interval = 2.5-19.5). In contrast, initial deterioration made endpoint improvement unlikely (0.33; 0.14-0.64). ADAS-Cog improvement and no change were each associated with GAS improvement. Initial ADAS-Cog worsening was unlikely to result in later improvement. ISRCTN26167328. Copyright © 2017. Published by Elsevier Inc.

  16. The brain-derived neurotrophic factor (BDNF val66met polymorphism differentially affects performance on subscales of the Wechsler memory scale – third edition (WMS-III

    Directory of Open Access Journals (Sweden)

    Yvette Nicole Lamb

    2015-08-01

    Full Text Available Single nucleotide polymorphisms in the brain-derived neurotrophic factor (BDNF gene and the catechol-O-methyltransferase (COMT gene influence brain structure and function, as well as cognitive abilities. They are most influential in the hippocampus and prefrontal cortex (PFC, respectively. Recall and recognition are forms of memory proposed to have different neural substrates, with recall having a greater dependence on the PFC and hippocampus. This study aimed to determine whether the BDNF val66met or COMT val158met polymorphisms differentially affect recall and recognition, and whether these polymorphisms interact. A sample of 100 healthy adults was assessed on recall and familiarity-based recognition using the Faces and Family Pictures subscales of the Wechsler Memory Scale – Third Edition (WMS-III. COMT genotype did not affect performance on either task. The BDNF polymorphism (i.e. met carriers relative to val homozygotes was associated with poorer recall ability, while not influencing recognition. Combining subscale scores in memory tests such as the WMS might obscure gene effects. Our results demonstrate the importance of distinguishing between recall and familiarity-based recognition in neurogenetics research.

  17. Are great apes able to reason from multi-item samples to populations of food items?

    Science.gov (United States)

    Eckert, Johanna; Rakoczy, Hannes; Call, Josep

    2017-10-01

    Inductive learning from limited observations is a cognitive capacity of fundamental importance. In humans, it is underwritten by our intuitive statistics, the ability to draw systematic inferences from populations to randomly drawn samples and vice versa. According to recent research in cognitive development, human intuitive statistics develops early in infancy. Recent work in comparative psychology has produced first evidence for analogous cognitive capacities in great apes who flexibly drew inferences from populations to samples. In the present study, we investigated whether great apes (Pongo abelii, Pan troglodytes, Pan paniscus, Gorilla gorilla) also draw inductive inferences in the opposite direction, from samples to populations. In two experiments, apes saw an experimenter randomly drawing one multi-item sample from each of two populations of food items. The populations differed in their proportion of preferred to neutral items (24:6 vs. 6:24) but apes saw only the distribution of food items in the samples that reflected the distribution of the respective populations (e.g., 4:1 vs. 1:4). Based on this observation they were then allowed to choose between the two populations. Results show that apes seemed to make inferences from samples to populations and thus chose the population from which the more favorable (4:1) sample was drawn in Experiment 1. In this experiment, the more attractive sample not only contained proportionally but also absolutely more preferred food items than the less attractive sample. Experiment 2, however, revealed that when absolute and relative frequencies were disentangled, apes performed at chance level. Whether these limitations in apes' performance reflect true limits of cognitive competence or merely performance limitations due to accessory task demands is still an open question. © 2017 Wiley Periodicals, Inc.

  18. 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.

  19. A Comparison of Anchor-Item Designs for the Concurrent Calibration of Large Banks of Likert-Type Items

    Science.gov (United States)

    Garcia-Perez, Miguel A.; Alcala-Quintana, Rocio; Garcia-Cueto, Eduardo

    2010-01-01

    Current interest in measuring quality of life is generating interest in the construction of computerized adaptive tests (CATs) with Likert-type items. Calibration of an item bank for use in CAT requires collecting responses to a large number of candidate items. However, the number is usually too large to administer to each subject in the…

  20. SURFACE APPLICATION OF ANTIOZONANTS TO RUBBER ITEMS AND EVALUATION OF ANTIOZONANTS FOR PACKAGING RUBBER ITEMS IN PLASTIC BAGS

    Science.gov (United States)

    Research was conducted to develop methods of surface applications of antiozonants to rubber items and evaluate antiozonants for packaging rubber...items in plastic bags. The report covers (1) tests of packaging rubber items in polyethylene bags together with various antiozonants , and (2) tests of

  1. Confirmatory Factor Analysis of the M5-50: An Implementation of the International Personality Item Pool Item Set

    Science.gov (United States)

    Socha, Alan; Cooper, Christopher A.; McCord, David M.

    2010-01-01

    Goldberg's International Personality Item Pool (IPIP; Goldberg, 1999) provides researchers with public-domain, free-access personality measurement scales that are proxies of well-established published scales. One of the more commonly used IPIP sets employs 50 items to measure the 5 broad domains of the 5-factor model, with 10 items per factor. The…

  2. Do Images Influence Assessment in Anatomy? Exploring the Effect of Images on Item Difficulty and Item Discrimination

    Science.gov (United States)

    Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2013-01-01

    Anatomists often use images in assessments and examinations. This study aims to investigate the influence of different types of images on item difficulty and item discrimination in written assessments. A total of 210 of 460 students volunteered for an extra assessment in a gross anatomy course. This assessment contained 39 test items grouped in…

  3. The Development of Practical Item Analysis Program for Indonesian Teachers

    Directory of Open Access Journals (Sweden)

    Ali Muhson

    2017-04-01

    Full Text Available Item analysis has essential roles in the learning assessment. The item analysis program is designed to measure student achievement and instructional effectiveness. This study was aimed to develop item-analysis program and verify its feasibility. This study uses a Research and Development (R & D model. The procedure includes designing and developing a product, validating, and testing the product. The data were collected through documentations, questionnaires, and interviews. This study successfully developed item analysis program, namely AnBuso. It is developed based on classical test theory (CTT. It was practical and applicable for Indonesian teachers to analyse test items

  4. Carbohydrate-Loading Diet

    Science.gov (United States)

    ... of your calories from carbohydrates. The role of carbohydrates Carbohydrates, also known as starches and sugars, are ... to consume some energy sources during your event. Carbohydrate loading Carbohydrate loading is done the week before ...

  5. Measurement invariance across educational levels and gender in 12-item Zarit Burden Interview (ZBI) on caregivers of people with dementia.

    Science.gov (United States)

    Lin, Chung-Ying; Ku, Li-Jung Elizabeth; Pakpour, Amir H

    2017-11-01

    The Zarit Burden Interview (ZBI) is a commonly used self-report to assess caregiver burden. A 12-item short form of the ZBI has been developed; however, its measurement invariance has not been examined across some different demographics. It is unclear whether different genders and educational levels of a population interpret the ZBI items similarly. Therefore, this study aimed to examine the measurement invariance of the 12-item ZBI across gender and educational levels in a Taiwanese sample. Caregivers who had a family member with dementia (n = 270) completed the ZBI through telephone interviews. Three confirmatory factor analysis (CFA) models were conducted: Model 1 was the configural model, Model 2 constrained all factor loadings, Model 3 constrained all factor loadings and item intercepts. Multiple group CFAs and the differential item functioning (DIF) contrast under Rasch analyses were used to detect measurement invariance across males (n = 100) and females (n = 170) and across educational levels of junior high schools and below (n = 86) and senior high schools and above (n = 183). The fit index differences between models supported the measurement invariance across gender and across educational levels (∆ comparative fit index (CFI) = -0.010 and 0.003; ∆ root mean square error of approximation (RMSEA) = -0.006 to 0.004). No substantial DIF contrast was found across gender and educational levels (value = -0.36 to 0.29). The ZBI is appropriate for combined use and for comparisons in caregivers across gender and different educational levels in Taiwan.

  6. 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

  7. 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

  8. Aspects of alienation and symptom load among adolescents

    DEFF Research Database (Denmark)

    Rayce, Signe L B; Holstein, Bjørn E; Kreiner, Svend

    2009-01-01

    ) correlation between each of the index's items and the outcomes and (iv) no differential item functioning. The final index included three indicators of alienation: helplessness, feeling left out of things and lack of confidentiality with parents. Symptom load was measured by HBSC Symptom Checklist and divided......BACKGROUND: The purpose was to examine the association between aspects of alienation and symptom load among adolescents. Furthermore an integrated purpose was to construct and validate an index of alienation. METHODS: Cross-sectional data from 5205 school children aged 11-15 years from a random...... sample of schools in Denmark were used. Data stems from the Danish contribution to the cross-national study Health and Behaviour in School-aged Children (HBSC). Alienation was measured with a new index fulfilling four criteria: (i) theoretical foundation, (ii) inter-correlation between items, (iii...

  9. Psychometric Evaluation of Chinese-Language 44-Item and 10-Item Big Five Personality Inventories, Including Correlations with Chronotype, Mindfulness and Mind Wandering.

    Directory of Open Access Journals (Sweden)

    Richard Carciofo

    Full Text Available The 44-item and 10-item Big Five Inventory (BFI personality scales are widely used, but there is a lack of psychometric data for Chinese versions. Eight surveys (total N = 2,496, aged 18-82, assessed a Chinese-language BFI-44 and/or an independently translated Chinese-language BFI-10. Most BFI-44 items loaded strongly or predominantly on the expected dimension, and values of Cronbach's alpha ranged .698-.807. Test-retest coefficients ranged .694-.770 (BFI-44, and .515-.873 (BFI-10. The BFI-44 and BFI-10 showed good convergent and discriminant correlations, and expected associations with gender (females higher for agreeableness and neuroticism, and age (older age associated with more conscientiousness and agreeableness, and also less neuroticism and openness. Additionally, predicted correlations were found with chronotype (morningness positive with conscientiousness, mindfulness (negative with neuroticism, positive with conscientiousness, and mind wandering/daydreaming frequency (negative with conscientiousness, positive with neuroticism. Exploratory analysis found that the Self-discipline facet of conscientiousness positively correlated with morningness and mindfulness, and negatively correlated with mind wandering/daydreaming frequency. Furthermore, Self-discipline was found to be a mediator in the relationships between chronotype and mindfulness, and chronotype and mind wandering/daydreaming frequency. Overall, the results support the utility of the BFI-44 and BFI-10 for Chinese-language big five personality research.

  10. Psychometric Evaluation of Chinese-Language 44-Item and 10-Item Big Five Personality Inventories, Including Correlations with Chronotype, Mindfulness and Mind Wandering.

    Science.gov (United States)

    Carciofo, Richard; Yang, Jiaoyan; Song, Nan; Du, Feng; Zhang, Kan

    2016-01-01

    The 44-item and 10-item Big Five Inventory (BFI) personality scales are widely used, but there is a lack of psychometric data for Chinese versions. Eight surveys (total N = 2,496, aged 18-82), assessed a Chinese-language BFI-44 and/or an independently translated Chinese-language BFI-10. Most BFI-44 items loaded strongly or predominantly on the expected dimension, and values of Cronbach's alpha ranged .698-.807. Test-retest coefficients ranged .694-.770 (BFI-44), and .515-.873 (BFI-10). The BFI-44 and BFI-10 showed good convergent and discriminant correlations, and expected associations with gender (females higher for agreeableness and neuroticism), and age (older age associated with more conscientiousness and agreeableness, and also less neuroticism and openness). Additionally, predicted correlations were found with chronotype (morningness positive with conscientiousness), mindfulness (negative with neuroticism, positive with conscientiousness), and mind wandering/daydreaming frequency (negative with conscientiousness, positive with neuroticism). Exploratory analysis found that the Self-discipline facet of conscientiousness positively correlated with morningness and mindfulness, and negatively correlated with mind wandering/daydreaming frequency. Furthermore, Self-discipline was found to be a mediator in the relationships between chronotype and mindfulness, and chronotype and mind wandering/daydreaming frequency. Overall, the results support the utility of the BFI-44 and BFI-10 for Chinese-language big five personality research.

  11. Psychometric Evaluation of Chinese-Language 44-Item and 10-Item Big Five Personality Inventories, Including Correlations with Chronotype, Mindfulness and Mind Wandering

    Science.gov (United States)

    Carciofo, Richard; Yang, Jiaoyan; Song, Nan; Du, Feng; Zhang, Kan

    2016-01-01

    The 44-item and 10-item Big Five Inventory (BFI) personality scales are widely used, but there is a lack of psychometric data for Chinese versions. Eight surveys (total N = 2,496, aged 18–82), assessed a Chinese-language BFI-44 and/or an independently translated Chinese-language BFI-10. Most BFI-44 items loaded strongly or predominantly on the expected dimension, and values of Cronbach's alpha ranged .698-.807. Test-retest coefficients ranged .694-.770 (BFI-44), and .515-.873 (BFI-10). The BFI-44 and BFI-10 showed good convergent and discriminant correlations, and expected associations with gender (females higher for agreeableness and neuroticism), and age (older age associated with more conscientiousness and agreeableness, and also less neuroticism and openness). Additionally, predicted correlations were found with chronotype (morningness positive with conscientiousness), mindfulness (negative with neuroticism, positive with conscientiousness), and mind wandering/daydreaming frequency (negative with conscientiousness, positive with neuroticism). Exploratory analysis found that the Self-discipline facet of conscientiousness positively correlated with morningness and mindfulness, and negatively correlated with mind wandering/daydreaming frequency. Furthermore, Self-discipline was found to be a mediator in the relationships between chronotype and mindfulness, and chronotype and mind wandering/daydreaming frequency. Overall, the results support the utility of the BFI-44 and BFI-10 for Chinese-language big five personality research. PMID:26918618

  12. The implications of content versus item validity on science tests

    Science.gov (United States)

    Yarroch, William L.

    The use of content validity as the primary assurance of the measurement accuracy for science assessment examinations is questioned. An alternative accuracy measure, item validity, is proposed. Item validity is based on research using qualitative comparisons between (a) student answers to objective items on the examination, (b) clinical interviews with examinees designed to ascertain their knowledge and understanding of the objective examination items, and (c) student answers to essay examination items prepared as an equivalent to the objective examination items. Calculations of item validity are used to show that selected objective items from the science assessment examination overestimated the actual student understanding of science content. Overestimation occurs when a student correctly answers an examination item, but for a reason other than that needed for an understanding of the content in question. There was little evidence that students incorrectly answered the items studied for the wrong reason, resulting in underestimation of the students' knowledge. The equivalent essay items were found to limit the amount of mismeasurement of the students' knowledge. Specific examples are cited and general suggestions are made on how to improve the measurement accuracy of objective examinations.

  13. 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).

  14. Identifying Unbiased Items for Screening Preschoolers for Disruptive Behavior Problems.

    Science.gov (United States)

    Studts, Christina R; Polaha, Jodi; van Zyl, Michiel A

    2017-05-01

    Efficient identification and referral to behavioral services are crucial in addressing early-onset disruptive behavior problems. Existing screening instruments for preschoolers are not ideal for pediatric primary care settings serving diverse populations. Eighteen candidate items for a new brief screening instrument were examined to identify those exhibiting measurement bias (i.e., differential item functioning, DIF) by child characteristics. Parents/guardians of preschool-aged children ( N = 900) from four primary care settings completed two full-length behavioral rating scales. Items measuring disruptive behavior problems were tested for DIF by child race, sex, and socioeconomic status using two approaches: item response theory-based likelihood ratio tests and ordinal logistic regression. Of 18 items, eight were identified with statistically significant DIF by at least one method. The bias observed in 8 of 18 items made them undesirable for screening diverse populations of children. These items were excluded from the new brief screening tool.

  15. Methodology for developing and evaluating the PROMIS smoking item banks.

    Science.gov (United States)

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

    2014-09-01

    This article describes the procedures used in the PROMIS Smoking Initiative for the development and evaluation of item banks, short forms (SFs), and computerized adaptive tests (CATs) for the assessment of 6 constructs related to cigarette smoking: nicotine dependence, coping expectancies, emotional and sensory expectancies, health expectancies, psychosocial expectancies, and social motivations for smoking. Analyses were conducted using response data from a large national sample of smokers. Items related to each construct were subjected to extensive item factor analyses and evaluation of differential item functioning (DIF). Final item banks were calibrated, and SF assessments were developed for each construct. The performance of the SFs and the potential use of the item banks for CAT administration were examined through simulation study. Item selection based on dimensionality assessment and DIF analyses produced item banks that were essentially unidimensional in structure and free of bias. Simulation studies demonstrated that the constructs could be accurately measured with a relatively small number of carefully selected items, either through fixed SFs or CAT-based assessment. Illustrative results are presented, and subsequent articles provide detailed discussion of each item bank in turn. The development of the PROMIS smoking item banks provides researchers with new tools for measuring smoking-related constructs. The use of the calibrated item banks and suggested SF assessments will enhance the quality of score estimates, thus advancing smoking research. Moreover, the methods used in the current study, including innovative approaches to item selection and SF construction, may have general relevance to item bank development and evaluation. © The Author 2013. 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.

  16. 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

  17. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  18. Cognitive Load and Cooperation

    DEFF Research Database (Denmark)

    Døssing, Felix Sebastian; Piovesan, Marco; Wengström, Erik Roland

    2017-01-01

    We study the effect of intuitive and reflective processes on cooperation using cognitive load. Compared with time constraint, which has been used in the previous literature, cognitive load is a more direct way to block reflective processes, and thus a more suitable way to study the link between...... intuition and cooperation. Using a repeated public goods game, we study the effect of different levels of cognitive load on contributions. We show that a higher cognitive load increases the initial level of cooperation. In particular, subjects are significantly less likely to fully free ride under high...... cognitive load....

  19. Are critical items "critical" for the MMPI-A.

    Science.gov (United States)

    Archer, R P; Jacobson, J M

    1993-12-01

    This article examines one aspect of the potential usefulness of critical items to the: Minnesota Multiphasic Personality Inventory -Adolescent (MMPI-A). Endorsement frequency data are presented on the Koss-Butcher (1973) and the Lachar-Wrobeli (1979) critical items for Minnesota Multiphasic Personality Inventory-2 (MMPI-2) adult normative and clinical samples and for MMPI-A adolescent normative and clinical samples. Adolescents in both normal and clinical samples endorse critical items with a higher frequency than do normal adults. Further, results demonstrated that significant differences were uniformly found between the endorsement frequencies for normative versus clinical subjects for the MMPI-2 samples, whereas similar comparisons for the MMPI-A samples typically showed that adolescents in clinical setting did not endorse critical items more frequently than normal adolescents. These findings indicate that it may be difficult to construct critical item lists for adolescents based on the type of empirical methodology used with adults in which items are selected based on endorsement frequency differences found between comparison group. Beyond the issue of the technical difficulty in creating a critical item list for adolescents, several conceptual concerns are raised regarding the application of critical items to the MMPI-A. It was noted that the concept of "critical items" has not been we11 defined, and both the reliability and validity of critical items may be limited in adolescent populations.

  20. A survey of theory and methods of invariant item ordering.

    Science.gov (United States)

    Sijtsma, K; Junker, B W

    1996-05-01

    In many testing situations, ordering the items by difficulty is helpful in analysing the testing data; examples include intelligence testing, analysis of differential item functioning, person-fit analysis, and exploring hypotheses about the order in which cognitive operations are acquired by children. In each situation, interpretation and analysis are made easier if the items are ordered by difficulty in the same way for every individual taking the test, i.e. the item response functions do not cross. This is an invariant item ordering. In this paper we review a class of non-parametric unidimensional item response models in which the ordinal properties of items (and persons) can be studied, and survey both old and new methods for the investigation of invariant item ordering in empirical data sets. Our model formulation derives in particular from the work of Holland & Rosenbaum (1986), Junker (1993) and Mokken (1971). We survey methods based on the work of Mokken (1971), Rosenbaum (1987a, b), and Sijtsma & Meijer (1992), and we also discuss some new proposals for checking invariant item ordering. When violations are detected, these methods allow a rough assessment of where on the latent scale the item response functions cross. We also study similarities and differences between these various methods and provide guidelines for their use. Finally, the methods are illustrated with data from a developmental psychology experiment in which the ability to draw inferences about transitive relations is explored.

  1. Editorial Changes and Item Performance: Implications for Calibration and Pretesting

    Directory of Open Access Journals (Sweden)

    Heather Stoffel

    2014-11-01

    Full Text Available Previous research on the impact of text and formatting changes on test-item performance has produced mixed results. This matter is important because it is generally acknowledged that any change to an item requires that it be recalibrated. The present study investigated the effects of seven classes of stylistic changes on item difficulty, discrimination, and response time for a subset of 65 items that make up a standardized test for physician licensure completed by 31,918 examinees in 2012. One of two versions of each item (original or revised was randomly assigned to examinees such that each examinee saw only two experimental items, with each item being administered to approximately 480 examinees. The stylistic changes had little or no effect on item difficulty or discrimination; however, one class of edits -' changing an item from an open lead-in (incomplete statement to a closed lead-in (direct question -' did result in slightly longer response times. Data for nonnative speakers of English were analyzed separately with nearly identical results. These findings have implications for the conventional practice of repretesting (or recalibrating items that have been subjected to minor editorial changes.

  2. Quantification of experienced hearing problems with item response theory.

    Science.gov (United States)

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

    2013-12-01

    The purpose of this study was to improve the effectiveness of adult hearing screens and demonstrate that interventions assessment methods are needed that address the individual's experienced hearing. Item response theory, which provides a methodology for assessing patient-reported outcomes, is examined here to demonstrate its usefulness in hearing screens and interventions. The graded response model is applied to a scale of 11 items assessing perceived hearing functioning and 10 items assessing experienced social limitations completed by a sample of 212 persons age 55+ years. Fixed and variable slope models are compared. Discrimination and threshold parameters are estimated and information functions evaluated. Variable slope models for both scales provided the best fit. The estimated discrimination parameters for all items except for one in each scale were good if not excellent (1.5-3.4). Threshold values varied, demonstrating the complementary and supplementary value of items within a scale. The information provided by each item varies relative to trait values so that each scale of items provides information over a wider range of trait values. Item response theory methodology facilitates the comparison of items relative to their discriminative ability and information provided and thus provides a basis for the selection of items for application in a screening setting.

  3. A comparative validation of the abbreviated Apathy Evaluation Scale (AES-10) with the Neuropsychiatric Inventory apathy subscale against diagnostic criteria of apathy.

    Science.gov (United States)

    Leontjevas, Ruslan; Evers-Stephan, Alexandra; Smalbrugge, Martin; Pot, Anne Margriet; Thewissen, Viviane; Gerritsen, Debby L; Koopmans, Raymond T C M

    2012-03-01

    To compare the Neuropsychiatric Inventory apathy subscale (NPIa) with the abbreviated Apathy Evaluation Scale (AES-10) on discriminant validity and on their performance to distinguish residents as apathetic or nonapathetic. Cross-sectional design. Nursing home. 100 residents of 4 dementia special care units (n = 58) and 3 somatic units (n = 42). Primary professional caregivers were interviewed to score the AES-10 and NPIa. The elderly care physician and the psychologist of each unit examined residents for clinical apathy using diagnostic criteria. The AES-10 and NPIa correlated moderately with each other (r(s) = 0.62, P AES-10 correlated weakly (r(s) = 0.27, P = .024) and the NPIa moderately (r(s) = 0.46, P = .001) with the Cornell Scale for Depression in Dementia. Receiver operating characteristic analysis showed an area under the curve (AUC) of 0.72 (P AES-10 and 0.67 (P AES-10 produced higher sums of sensitivity and negative predictive value than the NPIa. Explorative analyses revealed that both instruments produced higher scores in dementia independently of having an apathy diagnosis, whereas AUCs were significant in nondementia (AES-10: AUC = 0.88, P AES-10 and NPIa may be used to distinguish apathetic from nonapathetic residents in a heterogeneous sample with and without dementia, or in residents without dementia. The AES-10 may be preferable to the NPIa apathy subscale when ruling out or screening for apathy. The performance of the scales against diagnostic criteria of apathy in dementia need to be further examined. Copyright © 2012 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

  4. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of capacity causes high peaks in the energy price in the electricity market. Load control either reduces the electricity consumption during peak consumption and peak price or moves electricity consumption to some other time. The project Optimisation of Load Control is a part of the EDISON research program for distribution automation. The following areas were studied: Optimization of space heating and ventilation, when electricity price is time variable, load control model in power purchase optimization, optimization of direct load control sequences, interaction between load control optimization and power purchase optimization, literature on load control, optimization methods and field tests and response models of direct load control and the effects of the electricity market deregulation on load control. An overview of the main results is given in this chapter

  5. The basics of item response theory using R

    CERN Document Server

    Baker, Frank B

    2017-01-01

    This graduate-level textbook is a tutorial for item response theory that covers both the basics of item response theory and the use of R for preparing graphical presentation in writings about the theory. Item response theory has become one of the most powerful tools used in test construction, yet one of the barriers to learning and applying it is the considerable amount of sophisticated computational effort required to illustrate even the simplest concepts. This text provides the reader access to the basic concepts of item response theory freed of the tedious underlying calculations. It is intended for those who possess limited knowledge of educational measurement and psychometrics. Rather than presenting the full scope of item response theory, this textbook is concise and practical and presents basic concepts without becoming enmeshed in underlying mathematical and computational complexities. Clearly written text and succinct R code allow anyone familiar with statistical concepts to explore and apply item re...

  6. 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.

  7. Effects of question formats on student and item performance.

    Science.gov (United States)

    Caldwell, David J; Pate, Adam N

    2013-05-13

    To determine the effect of 3 variations in test item format on item statistics and student performance. Fifteen pairs of directly comparable test questions were written to adhere to (standard scale) or deviate from (nonstandard scale) 3 specific item-writing guidelines. Differences in item difficulty and discrimination were measured between the 2 scales as a whole and for each guideline individually. Student performance was also compared between the 2 scales. The nonstandard scale was 12.7 points more difficult than the standard scale (p=0.03). The guideline to avoid "none of the above" was the only 1 of the 3 guidelines to demonstrate significance. Students scored 53.6% and 41.3% (pstudents to answer correctly than the standard test items, provided no enhanced ability to discriminate between higher- and lower-performing students, and resulted in poorer student performance. Item-writing guidelines should be considered during test construction.

  8. Scientific Items in Cyprus Turkish Tales

    Directory of Open Access Journals (Sweden)

    Sevilay Atmaca

    2013-05-01

    Full Text Available Folk literature, which is a production of daily life experiences transferred from mouth to mouth, encompasses many types such as epic, legend, folk poetry, mania, laments, songs, riddles, tales, folk story, anecdote, proverbs, idioms, rhymes, and etc. These products, which represent the oral tradition of the people, transfer numerous information regarding the life experiences, beliefs, and values of their communities to the next generation. Tales are more attractive since they depict extraordinary events and because of these characteristics they are very didactic. These are some reasons why tales have a very significant place in Turkish folk literature. People have documented tales successfully transferring from a nomadic life to a settled one. This study attempts to determine the scientific elements in Cyprus Turkish Tales, as sample in the scope of the Turkish Tales, through content analysis. Researchers in this study will examine the themes in the selected tales such as “Earth and Cosmos”, “Physical Event”, “Matter and Change”, and “Living Organisms and Life”. They will also provide a code-list according to the themes found in the tales. Researchers will do a content analysis in relation to the themes and code-listing activities in “Cyprus Turkish Tales” collected by Mustafa Gökçeoğlu, a well-known Cyprus Turkish folk literature writer. It is seen from the research that living organism and life (f: 25 and matter and change (f: 24 themes have very abundant coded. It is followed with an orderly physical events theme (f: 13 and earth and cosmos theme (f: 6. As a result, it is seen that in samples which are taken from Turkish Cypriot Tales, scientific items are widely used. It is believed that the results of the study will give different perspectives to Turkish Language, literature, science-technology, and classroom teacher providing them with interdisciplinary and rich materials.

  9. The Comparison between National Final Examination Test Items and English Teacher Made-Test Items of 2010 and 2011

    Directory of Open Access Journals (Sweden)

    Khairil Razali

    2015-02-01

    Full Text Available The objective of the paper is to determine the relevance between the scope of the national final examination test items in English lesson and the English teacher made test items. It is also to identify the relevance between the deepness of national final examination test items in English subject and the English teacher made test item. The finding showed that  more than fifty percents of tryout out test items are not relevant with the national test items. Meanwhile, the final national test items were design with higher cognitive domain than teacher made test items. It means the teacher made test items (tryout is more superficial than final national test items. It can be a reason why the students who are can pass the tryout test which is made in teacher cannot pass the national final examination test (standardized test. It is expected that this study provides empirical evidence to devise on their optimal uses in EFL teaching.  Copyright © 2015 by Al-Ta'lim All right reserved

  10. Verification of Item Usage Rules in Product Configuration

    OpenAIRE

    Voronov, Alexey; Tidstam, Anna; Åkesson, Knut; MALMQVIST, Johan

    2012-01-01

    Part 2: PLM Ecosystem; International audience; In the development of complex products product configuration systems are often used to support the development process. Item Usage Rules (IURs) are conditions for including specific items in products bills of materials based on a high-level product description. Large number of items and significant complexity of IURs make it difficult to maintain and analyze IURs manually. In this paper we present an automated approach for verifying IURs, which g...

  11. Algorithms for computerized test construction using classical item parameters

    OpenAIRE

    Adema, Jos J.; van der Linden, Willem J.

    1989-01-01

    Recently, linear programming models for test construction were developed. These models were based on the information function from item response theory. In this paper another approach is followed. Two 0-1 linear programming models for the construction of tests using classical item and test parameters are given. These models are useful, for instance, when classical test theory has to serve as an interface between an IRT-based item banking system and a test constructor not familiar with the und...

  12. Safety Evaluation for Packaging (onsite) T Plant Canyon Items

    Energy Technology Data Exchange (ETDEWEB)

    OBRIEN, J.H.

    2000-07-14

    This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments.

  13. Three controversies over item disclosure in medical licensure examinations

    Directory of Open Access Journals (Sweden)

    Yoon Soo Park

    2015-09-01

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

  14. Test equating in the presence of DIF items.

    Science.gov (United States)

    Chu, Kwang-lee; Kamata, Akihito

    2005-01-01

    This paper proposes a multilevel measurement model that controls for DIF effects in test equating. The accuracy and stability of item and ability parameter estimates under the proposed multilevel measurement model were examined using randomly simulated data. Estimates from the proposed model were compared with those resulting from two multiple-group concurrent equating designs, including 1) a design that replaced DIF-items with items with no DIF; and 2) a design that retained DIF items with no attempt to control for DIF. In most of the investigated conditions, the results indicated that the proposed multilevel measurement model performed better than the two comparison models.

  15. 16PF-E Structure using Radial Parcels Versus Items.

    Science.gov (United States)

    Hughey, Joseph; Burdsal, Charles

    1982-07-01

    The Sixteen Personality Factor Questionnaire (16PF) was factored with the use of groups of items called radial parcels and was subsequently compared with an item factoring of the same data. This was done in order to verify the 16PF (Form E) primary factors and to investigate the use of radial parcels in that process. Ss were 449 physically or mentally handicapped men and women who were part of a rehabilitation counseling process. Results indicated that with some familiar exceptions factor identification and verification were complete. Moreover, the use of radial parcels maintained the dimensionality found in the items. Also, rotation toward simple structure proceeded more rapidly with parcels than with items.

  16. The Coexistence of Coping Resources and Specific Coping Styles in Stress: Evidence from Full Information Item Bifactor Analysis

    Science.gov (United States)

    Cui, Meng; Wu, Qing; Zhu, Xia; Miao, Danmin; Zhang, Yan; Feng, Xi; Xiao, Wei

    2014-01-01

    Background Knowledge of coping styles is useful in clinical diagnosis and suggesting specific therapeutic interventions. However, the latent structures and relationships between different aspects of coping styles have not been fully clarified. A full information item bifactor model will be beneficial to future research. Objective One goal of this study is identification of the best fit statistical model of coping styles. A second goal is entails extended analyses of latent relationships among different coping styles. In general, such research should offer greater understanding of the mechanisms of coping styles and provide insights into coping with stress. Methods Coping Styles Questionnaire (CSQ) and Generalized Self-Efficacy Scale (GSES) were administrated to officers suffering from military stress. Confirmatory Factor Analyses was performed to indentify the best fit model. A hierarchical item response model (bifactor model) was adopted to analyze the data. Additionally, correlations among coping styles and self-efficacy were compared using both original and bifactor models. Results Results showed a bifactor model best fit the data. Item loadings on general and specific factors varied among different coping styles. All items loaded significantly on the general factor, and most items also had moderate to large loadings on specific factors. The correlation between coping styles and self-efficacy and the correlation among different coping styles changed significantly after extracting the general factor of coping stress using bifactor analysis. This was seen in changes from positive (r = 0.714, pcoping styles have a bifactor structure. They also provide direct evidence of coexisting coping resources and styles. This further clarifies that dimensions of coping styles should include coping resources and specific coping styles. This finding has implications for measurement of coping mechanisms, health maintenance, and stress reduction. PMID:24787952

  17. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  18. Electrical load modeling

    Energy Technology Data Exchange (ETDEWEB)

    Valgas, Helio Moreira; Pinto, Roberto del Giudice R.; Franca, Carlos [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Lambert-Torres, Germano; Silva, Alexandre P. Alves da; Pires, Robson Celso; Costa Junior, Roberto Affonso [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    Accurate dynamic load models allow more precise calculations of power system controls and stability limits, which are critical mainly in the operation planning of power systems. This paper describes the development of a computer program (software) for static and dynamic load model studies using the measurement approach for the CEMIG system. Two dynamic load model structures are developed and tested. A procedure for applying a set of measured data from an on-line transient recording system to develop load models is described. (author) 6 refs., 17 figs.

  19. Critical Axial Load

    Directory of Open Access Journals (Sweden)

    Walt Wells

    2008-01-01

    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  20. Conditional recall and the frequency effect in the serial recall task: an examination of item-to-item associativity.

    Science.gov (United States)

    Miller, Leonie M; Roodenrys, Steven

    2012-11-01

    The frequency effect in short-term serial recall is influenced by the composition of lists. In pure lists, a robust advantage in the recall of high-frequency (HF) words is observed, yet in alternating mixed lists, HF and low-frequency (LF) words are recalled equally well. It has been argued that the preexisting associations between all list items determine a single, global level of supportive activation that assists item recall. Preexisting associations between items are assumed to be a function of language co-occurrence; HF-HF associations are high, LF-LF associations are low, and mixed associations are intermediate in activation strength. This account, however, is based on results when alternating lists with equal numbers of HF and LF words were used. It is possible that directional association between adjacent list items is responsible for the recall patterns reported. In the present experiment, the recall of three forms of mixed lists-those with equal numbers of HF and LF items and pure lists-was examined to test the extent to which item-to-item associations are present in serial recall. Furthermore, conditional probabilities were used to examine more closely the evidence for a contribution, since correct-in-position scoring may mask recall that is dependent on the recall of prior items. The results suggest that an item-to-item effect is clearly present for early but not late list items, and they implicate an additional factor, perhaps the availability of resources at output, in the recall of late list items.

  1. Aspects of alienation and symptom load among adolescents.

    Science.gov (United States)

    Rayce, Signe L B; Holstein, Bjørn E; Kreiner, Svend

    2009-01-01

    The purpose was to examine the association between aspects of alienation and symptom load among adolescents. Furthermore an integrated purpose was to construct and validate an index of alienation. Cross-sectional data from 5205 school children aged 11-15 years from a random sample of schools in Denmark were used. Data stems from the Danish contribution to the cross-national study Health and Behaviour in School-aged Children (HBSC). Alienation was measured with a new index fulfilling four criteria: (i) theoretical foundation, (ii) inter-correlation between items, (iii) correlation between each of the index's items and the outcomes and (iv) no differential item functioning. The final index included three indicators of alienation: helplessness, feeling left out of things and lack of confidentiality with parents. Symptom load was measured by HBSC Symptom Checklist and divided into physical and psychological symptoms respectively. High symptom load was defined as experiencing at least one symptom on a daily basis. The odds-ratio (OR) for high symptom load increased with the degree of alienation. For students with all three indicators of alienation, the OR for high physical symptom load was 2.49 (1.05-5.87). The OR for high psychological symptom load for the corresponding degree of alienation was 6.50 (3.11-13.56). The index of alienation fulfilled psychometric criteria for scalability. Furthermore the analyses showed a graded and significant association between alienation and high symptom load. This suggests alienation to be taken into account in future health interventions among adolescents. In school settings this may be done using principles of empowerment.

  2. 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.

  3. Force limited vibration testing: an evaluation of the computation of C2 for real load and probabilistic source

    NARCIS (Netherlands)

    Wijker, Jacob J; de Boer, Andries; Ellenbroek, Marcellinus Hermannus Maria

    2015-01-01

    To prevent over-testing of the test-item during random vibration testing Scharton proposed and discussed the force limited random vibration testing (FLVT) in a number of publications. Besides the random vibration specification, the total mass and the turn-over frequency of the load (test item), is a

  4. Item Response Theory: Introduction and Bibliography. Research Report No. 196.

    Science.gov (United States)

    Hambleton, Ronald K.

    A brief overview of item response theory is provided, and a 186-item bibliography of books and articles on the subject dating from 1953 to June 1989 is presented. The overview includes a definition of the theory, a discussion of its development and application, and comparisons with classical test theory. All publications in the bibliography were…

  5. 75 FR 71491 - Designation of Biobased Items for Federal Procurement

    Science.gov (United States)

    2010-11-23

    ..., and life- cycle costs of even a very small percentage of all products that may exist within an item... measures and life-cycle costs (the ASTM Standard D7075, ``Standard Practice for Evaluating and Reporting... health benefits, and life-cycle costs for each of the designated items. Information on the availability...

  6. 17 CFR 229.407 - (Item 407) Corporate governance.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 407) Corporate governance. 229.407 Section 229.407 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION....407 (Item 407) Corporate governance. (a) Director independence. Identify each director and, when the...

  7. Mathematical-programming approaches to test item pool design

    NARCIS (Netherlands)

    Veldkamp, Bernard P.; van der Linden, Willem J.; Ariel, A.

    2002-01-01

    This paper presents an approach to item pool design that has the potential to improve on the quality of current item pools in educational and psychological testing andhence to increase both measurement precision and validity. The approach consists of the application of mathematical programming

  8. Description of a food parenting practice item bank

    Science.gov (United States)

    Several recent reviews have highlighted the large number of instruments currently available to assess food parenting practices (FPP). In order to foster development of instruments that assess behaviorally significant FPP domains with appropriate items, an item bank of FPP is being developed, populat...

  9. Item-Specific and Interitem Elaboration in Recall and Recognition

    Science.gov (United States)

    1984-07-01

    However, increasing task difficulty, resulting in a more istinctive encoding for items, plays a larger role in recognition. In a similar vein, Belleza ...and his collegues ( Belleza , Cheesman & Reddy 1977) have demonstrated that organizational strategies, such as the alphabet and story mnemonics, aid...specific semantic processing (Craik & Tulving, 1975). Presumably, some item-specific semantic processing occurs prior to or during organization ( Belleza

  10. Effects of Aging and IQ on Item and Associative Memory

    Science.gov (United States)

    Ratcliff, Roger; Thapar, Anjali; McKoon, Gail

    2011-01-01

    The effects of aging and IQ on performance were examined in 4 memory tasks: item recognition, associative recognition, cued recall, and free recall. For item and associative recognition, accuracy and the response time (RT) distributions for correct and error responses were explained by Ratcliff's (1978) diffusion model at the level of individual…

  11. Dissociation between source and item memory in Parkinson's disease.

    Science.gov (United States)

    Hu, Panpan; Li, Youhai; Ma, Huijuan; Xi, Chunhua; Chen, Xianwen; Wang, Kai

    2014-01-01

    Episodic memory includes information about item memory and source memory. Many researches support the hypothesis that these two memory systems are implemented by different brain structures. The aim of this study was to investigate the characteristics of item memory and source memory processing in patients with Parkinson's disease (PD), and to further verify the hypothesis of dual-process model of source and item memory. We established a neuropsychological battery to measure the performance of item memory and source memory. Totally 35 PD individuals and 35 matched healthy controls (HC) were administrated with the battery. Item memory task consists of the learning and recognition of high-frequency national Chinese characters; source memory task consists of the learning and recognition of three modes (character, picture, and image) of objects. Compared with the controls, the idiopathic PD patients have been impaired source memory (PD vs. HC: 0.65 ± 0.06 vs. 0.72 ± 0.09, P = 0.001), but not impaired in item memory (PD vs. HC: 0.65 ± 0.07 vs. 0.67 ± 0.08, P = 0.240). The present experiment provides evidence for dissociation between item and source memory in PD patients, thereby strengthening the claim that the item or source memory rely on different brain structures. PD patients show poor source memory, in which dopamine plays a critical role.

  12. 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 ...

  13. A Statistical Test for Differential Item Pair Functioning

    NARCIS (Netherlands)

    Bechger, T.M.; Maris, G.

    This paper presents an IRT-based statistical test for differential item functioning (DIF). The test is developed for items conforming to the Rasch (Probabilistic models for some intelligence and attainment tests, The Danish Institute of Educational Research, Copenhagen, 1960) model but we will

  14. Detection of differential item functioning using Lagrange multiplier tests

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    1996-01-01

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

  15. Algorithms for computerized test construction using classical item parameters

    NARCIS (Netherlands)

    Adema, Jos J.; van der Linden, Willem J.

    1989-01-01

    Recently, linear programming models for test construction were developed. These models were based on the information function from item response theory. In this paper another approach is followed. Two 0-1 linear programming models for the construction of tests using classical item and test

  16. Using response times for item selection in adaptive testing

    NARCIS (Netherlands)

    van der Linden, Willem J.

    2008-01-01

    Response times on items can be used to improve item selection in adaptive testing provided that a probabilistic model for their distribution is available. In this research, the author used a hierarchical modeling framework with separate first-level models for the responses and response times and a

  17. Limited Nomination Reliability Using Single- and Multiple-item Measures

    NARCIS (Netherlands)

    Babcock, B.; Marks, P.E.L.; Crick, N.R.; Cillessen, A.H.N.

    2014-01-01

    This article examines a variety of reliability issues as related to limited nomination sociometric measures. Peer nomination data were collected from 77 sixth grade classrooms. Results showed that, although some single-item peer nomination measures were relatively reliable, many single-item peer

  18. A person fit test for IRT models for polytomous items

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; Dagohoy, A.V.

    2007-01-01

    A person fit test based on the Lagrange multiplier test is presented for three item response theory models for polytomous items: the generalized partial credit model, the sequential model, and the graded response model. The test can also be used in the framework of multidimensional ability

  19. Editorial Changes and Item Performance: Implications for Calibration and Pretesting

    Science.gov (United States)

    Stoffel, Heather; Raymond, Mark R.; Bucak, S. Deniz; Haist, Steven A.

    2014-01-01

    Previous research on the impact of text and formatting changes on test-item performance has produced mixed results. This matter is important because it is generally acknowledged that "any" change to an item requires that it be recalibrated. The present study investigated the effects of seven classes of stylistic changes on item…

  20. Elu kui näitemäng / Helju Koger

    Index Scriptorium Estoniae

    Koger, Helju, 1943-

    2007-01-01

    VI kihelkonnapäevadest Juurus. Juuru Mihkli kirikus esines ansambel Resonabilis. Konverentsil räägiti Järlepa mõisast, Anu Allikvee pidas ettekande "August von Kotzebue elu nagu näitemäng" jm. Näitemängu "Pärmi Jaagu unenägu" nägi kohalike asjaarmastajate esituses

  1. A Primer on Ways To Explore Item Bias.

    Science.gov (United States)

    Cromwell, Susan

    This paper provides an introductory primer on methods for exploring item bias. The purposes of item bias analysis are to investigate whether test scores are affected by different sources of variance in the various subpopulations, and if different sources of variance are found, to determine if an unfair advantage exists. The review discusses three…

  2. 38 CFR 59.90 - Line item adjustments to grants.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Line item adjustments to grants. 59.90 Section 59.90 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) GRANTS TO STATES FOR CONSTRUCTION OR ACQUISITION OF STATE HOMES § 59.90 Line item adjustments to...

  3. Creating a Database for Test Items in National Examinations (pp ...

    African Journals Online (AJOL)

    Nekky Umera

    vested on computer programmers and the labour turnover of programming staff was usually very high. The implication of this ..... test items banking; skills in test development, test moderation, item analysis with a good programming practice are ..... “A Web-based System for Automatic Language Skill. Assessment: EVALING”.

  4. Nested Logit Models for Multiple-Choice Item Response Data

    Science.gov (United States)

    Suh, Youngsuk; Bolt, Daniel M.

    2010-01-01

    Nested logit item response models for multiple-choice data are presented. Relative to previous models, the new models are suggested to provide a better approximation to multiple-choice items where the application of a solution strategy precedes consideration of response options. In practice, the models also accommodate collapsibility across all…

  5. Data Visualization of Item-Total Correlation by Median Smoothing

    Science.gov (United States)

    Yu, Chong Ho; Douglas, Samantha; Lee, Anna; An, Min

    2016-01-01

    This paper aims to illustrate how data visualization could be utilized to identify errors prior to modeling, using an example with multi-dimensional item response theory (MIRT). MIRT combines item response theory and factor analysis to identify a psychometric model that investigates two or more latent traits. While it may seem convenient to…

  6. Studies on statistical models for polytomously scored test items

    NARCIS (Netherlands)

    Akkermans, Wies

    1998-01-01

    This dissertation, which is structured as a collection of self-contained papers, will be concerned mainly with di�erences between item response models. The purpose of item response theory (IRT) is estimation of a hypothesized latent variable, such as, for example, intelligence or ability in

  7. 17 CFR 229.406 - (Item 406) Code of ethics.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 406) Code of ethics. 229... 406) Code of ethics. (a) Disclose whether the registrant has adopted a code of ethics that applies to... code of ethics, explain why it has not done so. (b) For purposes of this Item 406, the term code of...

  8. Machine-Scored Testing, Part II: Creativity and Item Analysis.

    Science.gov (United States)

    Leuba, Richard J.

    1986-01-01

    Explains how multiple choice test items can be devised to measure higher-order learning, including engineering problem solving. Discusses the value and information provided in item analysis procedures with machine-scored tests. Suggests elements to consider in test design. (ML)

  9. Semiparametric Item Response Functions in the Context of Guessing

    Science.gov (United States)

    Falk, Carl F.; Cai, Li

    2016-01-01

    We present a logistic function of a monotonic polynomial with a lower asymptote, allowing additional flexibility beyond the three-parameter logistic model. We develop a maximum marginal likelihood-based approach to estimate the item parameters. The new item response model is demonstrated on math assessment data from a state, and a computationally…

  10. Capitalization on item calibration error in computer adaptive testing

    NARCIS (Netherlands)

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

    2006-01-01

    In adaptive testing, item selection is sequentially optimized during the test. Since the optimization takes place over a pool of items calibrated with estimation error, capitalization on these errors is likely to occur. How serious the consequences of this phenomenon are depends not only on the

  11. Capitalization on item calibration error in adaptive testing

    NARCIS (Netherlands)

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

    2000-01-01

    In adaptive testing, item selection is sequentially optimized during the test. Because the optimization takes place over a pool of items calibrated with estimation error, capitalization on chance is likely to occur.Howserious the consequences of this phenomenon are depends not only on the

  12. Capitalization on item calibration error in adaptive testing

    NARCIS (Netherlands)

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

    1998-01-01

    In adaptive testing, item selection is sequentially optimized during the test. Since the optimization takes place over a pool of items calibrated with estimation error, capitalization on these errors is likely to occur. How serious the consequences of this phenomenon are depends not only on the

  13. Creating a Database for Test Items in National Examinations ...

    African Journals Online (AJOL)

    This paper looks at how to generate questions for national and local examinations without putting such questions (Items) at risk of leakage; reduce cost and time taken for such activities like time consuming items analysis and moderation; and improve on the poor selection which often characterized manually generated ...

  14. Comparing optimization algorithms for item selection in Mokken scale analysis

    NARCIS (Netherlands)

    Straat, J.H.; van der Ark, L.A.; Sijtsma, K.

    2013-01-01

    Mokken scale analysis uses an automated bottom-up stepwise item selection procedure that suffers from two problems. First, when selected during the procedure items satisfy the scaling conditions but they may fail to do so after the scale has been completed. Second, the procedure is approximate and

  15. Distinguishing between Net and Global DIF in Polytomous Items

    Science.gov (United States)

    Penfield, Randall D.

    2010-01-01

    In this article, I address two competing conceptions of differential item functioning (DIF) in polytomously scored items. The first conception, referred to as net DIF, concerns between-group differences in the conditional expected value of the polytomous response variable. The second conception, referred to as global DIF, concerns the conditional…

  16. 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

  17. Load Induced Blindness

    Science.gov (United States)

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of…

  18. eHealth literacy in chronic disease patients: An item response theory analysis of the eHealth literacy scale (eHEALS).

    Science.gov (United States)

    Paige, Samantha R; Krieger, Janice L; Stellefson, Michael; Alber, Julia M

    2017-02-01

    Chronic disease patients are affected by low computer and health literacy, which negatively affects their ability to benefit from access to online health information. To estimate reliability and confirm model specifications for eHealth Literacy Scale (eHEALS) scores among chronic disease patients using Classical Test (CTT) and Item Response Theory techniques. A stratified sample of Black/African American (N=341) and Caucasian (N=343) adults with chronic disease completed an online survey including the eHEALS. Item discrimination was explored using bi-variate correlations and Cronbach's alpha for internal consistency. A categorical confirmatory factor analysis tested a one-factor structure of eHEALS scores. Item characteristic curves, in-fit/outfit statistics, omega coefficient, and item reliability and separation estimates were computed. A 1-factor structure of eHEALS was confirmed by statistically significant standardized item loadings, acceptable model fit indices (CFI/TLI>0.90), and 70% variance explained by the model. Item response categories increased with higher theta levels, and there was evidence of acceptable reliability (ω=0.94; item reliability=89; item separation=8.54). eHEALS scores are a valid and reliable measure of self-reported eHealth literacy among Internet-using chronic disease patients. Providers can use eHEALS to help identify patients' eHealth literacy skills. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. AVOID BECOMING A VICTIM OF COUNTERFEIT ITEMS

    Energy Technology Data Exchange (ETDEWEB)

    WARRINER RD

    2011-07-13

    In today's globalized economy, we cannot live without imported products. Most people do not realize how thin the safety net of regulation and inspection really is. Less than three percent of imported products receive any form of government inspection prior to sale. Avoid flea markets, street vendors and deep discount stores. The sellers of counterfeit wares know where to market their products. They look for individuals who are hungry for a brand name item but do not want to pay a brand name price for it. The internet provides anonymity to the sellers of counterfeit products. Unlike Europe, U.S. law does not hold internet-marketing organizations, responsible for the quality of the products sold on their websites. These organizations will remove an individual vendor when a sufficient number of complaints are lodged, but they will not take responsibility for the counterfeit products you may have purchased. EBay has a number of counterfeit product guides to help you avoid being a victim of the sellers of these products. Ten percent of all medications taken worldwide are counterfeit. If you do buy medications on-line, be sure that the National Association of Boards of Pharmacy Verified Internet Pharmacy Practice Sites (VIPPS) recommends the pharmacy you choose to use. Inspect all medication purchases and report any change in color, shape, imprinting or odor to your pharmacist. If you take generic medications these attributes may change from one manufacturer to another. Your pharmacist should inform you of any changes when you refill your prescription. If they do not, get clarification prior to taking the medication. Please note that the Federal Drug Administration (FDA) does not regulate supplements. The FDA only steps in when a specific supplement proves to cause physical harm or contains a regulated ingredient. Due to counterfeiting, Underwriters Laboratories (UL) changed their label design three times since 1996. The new gold label should be attached to the cord

  20. 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.

  1. Comparison of Polytomous Parametric and Nonparametric Item Response Theory Models

    Directory of Open Access Journals (Sweden)

    Özge BIKMAZ BİLGEN

    2017-12-01

    Full Text Available This research aimed to identify the effects of independent variables as sample size, sample distribution, the number of items in the test, and the number of response categories of items in the test on the estimations of Graded Response Model (GRM under Parametric Item Response Theory (PIRT and by Monotone Homogeneity Model (MHM under Non-Parametric Item Response Theory (NIRT for polytomously scored items. To achieve this aim, the research was performed as a fundamental study in which 192 simulation conditions were designed by the combination of sample size, sample distribution, the number of items, and the number of categories of items. Estimates by GRM and MHM were examined under different levels of sample size (N= 100, 250, 500, 1000, sample distribution (normal, skewed, the number of items (10, 20, 40, 80, and the number of categories of items (3, 5, 7 conditions, by respectively calculating model-data fit, reliability values, standart errors of parameters. As a result of the research, it was found that since the values used to evaluate model-data fit were influenced by the increase of variable while calculating model-data fit and since they can not be interpreted alone, it is difficult to compare and generalize the results. The practical calculation of model data fit, which can be interpreted without the need for another value, in MHM provides superiority over GRM. Another research result is that the reliability values give similar results for both models. The standard errors of the MHM parameter estimates is lower than the GRM estimates under small sample and few items conditions and the standard errors of the MHM parameter estimates are close to each other in all conditions.

  2. SPEARMAN'S HYPOTHESIS TESTED COMPARING SAUDI ARABIAN CHILDREN AND ADOLESCENTS WITH VARIOUS OTHER GROUPS OF CHILDREN AND ADOLESCENTS ON THE ITEMS OF THE STANDARD PROGRESSIVE MATRICES.

    Science.gov (United States)

    Te NijenhuiS, Jan; Batterjee, Adel A; Van Den Hoek, Michael; Allik, Jüri; Sukhanovskiy, Vladimir

    2017-09-01

    Spearman's hypothesis tested at the level of items states that differences between ethnic groups on the items of an IQ test are a function of the g loadings of these items, such that there are small differences between ethnic groups on items with low g loadings and large differences between ethnic groups on items with high g loadings; this has been confirmed in a limited number of studies. In this paper, Spearman's hypothesis was tested, comparing a group of Saudi children and adolescents (N=3209) with other groups of children and adolescents from Denmark, Cyprus, Croatia, Bosnia, South Africa, Estonia, Ukraine, Ireland, Russia and Chile (total N=9333). The analyses were carried out on twelve comparisons between the Saudi Arabian children and the other children. Spearman's hypothesis was confirmed less strongly than in other large-scale studies with a mean weighted r value of 0.44. The relevance of these findings for the discussion on the causes of group differences is discussed.

  3. Establishing a Common Metric for Physical Function: Linking the HAQ-DI and SF-36 PF Subscale to PROMIS(®) Physical Function.

    Science.gov (United States)

    Schalet, Benjamin D; Revicki, Dennis A; Cook, Karon F; Krishnan, Eswar; Fries, Jim F; Cella, David

    2015-10-01

    Physical function (PF) is a common health concept measured in clinical trials and clinical care. It is measured with different instruments that are not directly comparable, making comparative effectiveness research (CER) challenging when PF is the outcome of interest. Our goal was to establish a common reporting metric, so that scores on commonly used physical function measures can be converted into PROMIS scores. Following a single-sample linking design, all participants completed items from the NIH Patient Reported Outcomes Measurement Information System (PROMIS®) Physical Function (PROMIS PF) item bank and at least one other commonly used "legacy" measure: the Health Assessment Questionnaire (HAQ) or the Short Form-36 physical function ten-item PF scale (SF-36 PF). A common metric was created using analyses based on item response theory (IRT), producing score cross-walk tables. Participants (N = 733) were part of an internet panel, many of whom reported one or more chronic health conditions. PROMIS PF, SF-36 PF, and the HAQ-Disability Index (HAQ-DI). Our results supported the hypothesis that all three scales measure essentially the same concept. Cross-walk tables for use in CER are therefore justified. HAQ-DI and SF-36 PF results can be expressed on the PROMIS PF metric for the purposes of CER and other efforts to compare PF results across studies that utilize any one of these three measures. Clinicians seeking to incorporate PROs into their clinics can collect patient data on any one of these three instruments and estimate the equivalent on the other two.

  4. 41 CFR 101-26.605 - Items other than petroleum products and electronic items available from the Defense Logistics...

    Science.gov (United States)

    2010-07-01

    ... petroleum products and electronic items available from the Defense Logistics Agency. 101-26.605 Section 101... available from the Defense Logistics Agency. Agencies required to use GSA supply sources should also use... Logistics Agency, the catalog will contain only those items in Federal supply classification classes which...

  5. The use of predicted values for item parameters in item response theory models: An application in intelligence tests

    NARCIS (Netherlands)

    Matteucci, M.; S. Mignani, Prof.; Veldkamp, Bernard P.

    2012-01-01

    In testing, item response theory models are widely used in order to estimate item parameters and individual abilities. However, even unidimensional models require a considerable sample size so that all parameters can be estimated precisely. The introduction of empirical prior information about

  6. Generalizability and Dependability of Single-Item and Multiple-Item Direct Behavior Rating Scales for Engagement and Disruptive Behavior

    Science.gov (United States)

    Volpe, Robert J.; Briesch, Amy M.

    2012-01-01

    Direct behavior rating (DBR) has been described as a hybrid of systematic direct observation and behavior rating scales. Although single-item (DBR-SIS) and multi-item (DBR-MIS) methods have been advocated, the overwhelming majority of research attention has focused on DBR-SIS. This study employed generalizability theory to compare the…

  7. Exploring the Relevance of Items in the Communicative Participation Item Bank (CPIB) for Individuals With Hearing Loss

    Science.gov (United States)

    Baylor, Carolyn R.; Birch, Kristen; Yorkston, Kathryn M.

    2017-01-01

    Purpose The Communicative Participation Item Bank (CPIB) was developed to evaluate participation restrictions in communication situations for individuals with speech and language disorders. This study evaluated the potential relevance of CPIB items for individuals with hearing loss. Method Cognitive interviews were conducted with 17 adults with a range of treated and untreated hearing loss, who responded to 46 items. Interviews were continued until saturation was reached and prevalent trends emerged. A focus group was also conducted with 3 experienced audiologists to seek their views on the CPIB. Analysis of data included qualitative and quantitative approaches. Results The majority of the items were applicable to individuals with hearing loss; however, 12 items were identified as potentially not relevant. This was largely attributed to the items' focus on speech production rather than hearing. The results from the focus group were in agreement for a majority of items. Conclusions The next step in validating the CPIB for individuals with hearing loss is a psychometric analysis on a large sample. Possible outcomes could be that the CPIB is considered valid in its entirety or the creation of a new questionnaire or a hearing loss–specific short form with a subset of items is necessary. PMID:28114665

  8. The Academic Medical Center Linear Disability Score (ALDS) item bank: item response theory analysis in a mixed patient population

    NARCIS (Netherlands)

    Holman, Rebecca; Weisscher, Nadine; Glas, Cees A. W.; Dijkgraaf, Marcel G. W.; Vermeulen, Marinus; de Haan, Rob J.; Lindeboom, Robert

    2005-01-01

    BACKGROUND: Currently, there is a lot of interest in the flexible framework offered by item banks for measuring patient relevant outcomes. However, there are few item banks, which have been developed to quantify functional status, as expressed by the ability to perform activities of daily life. This

  9. The academic medical center linear disability score (ALDS) item bank: item response theory analysis in a mixed patient population

    NARCIS (Netherlands)

    Holman, Rebecca; Weisscher, Nadine; Glas, Cornelis A.W.; Dijkgraaf, Marcel G.W.; Vermeulen, Martinus; de Haan, Rob J.; Lindeboom, Robert

    2005-01-01

    Background: Currently, there is a lot of interest in the flexible framework offered by item banks for measuring patient relevant outcomes. However, there are few item banks, which have been developed to quantify functional status, as expressed by the ability to perform activities of daily life. This

  10. More is not Always Better: The Relation between Item Response and Item Response Time in Raven’s Matrices

    Directory of Open Access Journals (Sweden)

    Frank Goldhammer

    2015-03-01

    Full Text Available The role of response time in completing an item can have very different interpretations. Responding more slowly could be positively related to success as the item is answered more carefully. However, the association may be negative if working faster indicates higher ability. The objective of this study was to clarify the validity of each assumption for reasoning items considering the mode of processing. A total of 230 persons completed a computerized version of Raven’s Advanced Progressive Matrices test. Results revealed that response time overall had a negative effect. However, this effect was moderated by items and persons. For easy items and able persons the effect was strongly negative, for difficult items and less able persons it was less negative or even positive. The number of rules involved in a matrix problem proved to explain item difficulty significantly. Most importantly, a positive interaction effect between the number of rules and item response time indicated that the response time effect became less negative with an increasing number of rules. Moreover, exploratory analyses suggested that the error type influenced the response time effect.

  11. Do images influence assessment in anatomy? Exploring the effect of images on item difficulty and item discrimination.

    NARCIS (Netherlands)

    Vorstenbosch, M.A.T.M.; Klaassen, T.P.; Kooloos, J.G.M.; Bolhuis, S.M.; Laan, R.F.J.M.

    2013-01-01

    Anatomists often use images in assessments and examinations. This study aims to investigate the influence of different types of images on item difficulty and item discrimination in written assessments. A total of 210 of 460 students volunteered for an extra assessment in a gross anatomy course. This

  12. Creation of New Items and Forms for the Project A Assembling Objects Test

    Science.gov (United States)

    1994-08-01

    correct; D, a measure of item discrimination - the rpbi , between the item score (correct or incorrect) and the total score on the 36 original items...D2 another measure of item discrimination - the rpbis between the item score and the total score on the 18 original items of the same type (marked

  13. Remembered but Unused: The Accessory Items in Working Memory that Do Not Guide Attention

    Science.gov (United States)

    Peters, Judith C.; Goebel, Rainer; Roelfsema, Pieter R.

    2009-01-01

    If we search for an item, a representation of this item in our working memory guides attention to matching items in the visual scene. We can hold multiple items in working memory. Do all these items guide attention in parallel? We asked participants to detect a target object in a stream of objects while they maintained a second item in memory for…

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

    Science.gov (United States)

    Magis, David; Facon, Bruno

    2013-01-01

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

  15. Mechanism isolates load weighing cell during lifting of load

    Science.gov (United States)

    Haigler, J. S.

    1966-01-01

    Load weighing cell used in conjuction with a hoist is isolated during lifting and manipulation of the load. A simple mechanism, attached to a crane hook, provides a screw adjustment for engaging the load cell during weighing of the load and isolating it from lift forces during hoisting of the load.

  16. Load flow analysis using decoupled fuzzy load flow under critical ...

    African Journals Online (AJOL)

    user

    The conventional load flow methods like Newton-Raphson load flow (NRLF), Fast Decoupled load flow (FDLF) provide poor performance under critical conditions such as high R/X ratio, heavily loading condition etc. Exploiting the decoupling properties of power system, reliable fuzzy load flow is developed to overcome the ...

  17. Task Performance induced Work Load in Nursing

    Directory of Open Access Journals (Sweden)

    Shirazeh Arghami

    2015-12-01

    Full Text Available Background & objective: High workload may lead to increase human errors, compromise quality and safety of care, and reduce the nurses’ quality of working life. The aim of this study is to determine the task-induced workload in nursing. Methods: This is a descriptive analytical study. All of 214 nurses of one of the educational hospital took part in. After obtaining informed consent from participants, data were collected based on NASA-TLX questionnaire and the desired level assumed less than 50%. Analysis of data was performed by descriptive statistics and Anova in SPSS software (version 11. 0 at significant level of 0.05. Results: The results showed that perceived mental pressure for nurses is more than other NASA-TLX subscales (P< .001. Also, the mean perceived workload was more than 50%. However, mean workload score of NASA-TLX showed significant correlation with age (P< .001, work experience (P< .001, shift work (P< .02, and department (P< .001. Conclusion: The results show that effective programs will be required to reduce the work load, and to enhance nurses' performance

  18. Industrial application of fluidized bed combustion. Phase I, task 4: sub-scale unit testing and data analysis. Volume I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goodstine, S.L.; Accortt, J.I.; Harris, R.D.; Kantersaria, P.P.; Matthews, F.T.; Jones, B.C.; Jukkola, G.D.

    1979-12-01

    Combustion Engineering, under contract with the Department of Energy, has developed, designed, and is constructing a 50,000 lbs steam/hr Industrial FBC Demonstration Plant. The plant will provide steam for space heating at the Great Lakes Naval Base in North Chicago, Illinois. Its operation will enable industry to objectively appraise the performance, reliability, and economics of FBC technology. A hot sub-scale unit (SSU), simulating the operating conditions of the demonstration plant, has been constructed and operated at Combustion Engineering's Kreisinger Development Laboratory in Windsor, Connecticut. The SSU facility has served as a valuable developmental tool in establishing the performance characteristics of the FBC process and equipment as used in the larger Demonstration Plant. Experience gained during more than 2000 hours of operation, including the analytical results derived from an extensive test program of 1500 hours operation, has defined problems and identified solutions in engineering the larger FBC Demonstration Plant. This report presents documentation of the results of the SSU test program.

  19. Environmentally Responsible Aviation (ERA) Project - N+2 Advanced Vehicle Concepts Study and Conceptual Design of Subscale Test Vehicle (STV) Final Report

    Science.gov (United States)

    Bonet, John T.; Schellenger, Harvey G.; Rawdon, Blaine K.; Elmer, Kevin R.; Wakayama, Sean R.; Brown, Derrell L.; Guo, Yueping

    2011-01-01

    NASA has set demanding goals for technology developments to meet national needs to improve fuel efficiency concurrent with improving the environment to enable air transportation growth. A figure shows NASA's subsonic transport system metrics. The results of Boeing ERA N+2 Advanced Vehicle Concept Study show that the Blended Wing Body (BWB) vehicle, with ultra high bypass propulsion systems have the potential to meet the combined NASA ERA N+2 goals. This study had 3 main activities. 1) The development of an advanced vehicle concepts that can meet the NASA system level metrics. 2) Identification of key enabling technologies and the development of technology roadmaps and maturation plans. 3) The development of a subscale test vehicle that can demonstrate and mature the key enabling technologies needed to meet the NASA system level metrics. Technology maturation plans are presented and include key performance parameters and technical performance measures. The plans describe the risks that will be reduced with technology development and the expected progression of technical maturity.

  20. Sub-Scale Orion Parachute Test Results from the National Full-Scale Aerodynamics Complex 80- By 120-ft Wind Tunnel

    Science.gov (United States)

    Anderson, Brian P.; Greathouse, James S.; Powell, Jessica M.; Ross, James C.; Schairer, Edward T.; Kushner, Laura; Porter, Barry J.; Goulding, Patrick W., II; Zwicker, Matthew L.; Mollmann, Catherine

    2017-01-01

    A two-week test campaign was conducted in the National Full-Scale Aerodynamics Complex 80 x 120-ft Wind Tunnel in support of Orion parachute pendulum mitigation activities. The test gathered static aerodynamic data using an instrumented, 3-tether system attached to the parachute vent in combination with an instrumented parachute riser. Dynamic data was also gathered by releasing the tether system and measuring canopy performance using photogrammetry. Several canopy configurations were tested and compared against the current Orion parachute design to understand changes in drag performance and aerodynamic stability. These configurations included canopies with varying levels and locations of geometric porosity as well as sails with increased levels of fullness. In total, 37 runs were completed for a total of 392 data points. Immediately after the end of the testing campaign a down-select decision was made based on preliminary data to support follow-on sub-scale air drop testing. A summary of a more rigorous analysis of the test data is also presented.

  1. Development of a Parent-Report Cognitive Function Item Bank Using Item Response Theory and Exploration of its Clinical Utility in Computerized Adaptive Testing

    National Research Council Canada - National Science Library

    Lai, Jin-Shei; Butt, Zeeshan; Zelko, Frank; Cella, David; Krull, Kevin R; Kieran, Mark W; Goldman, Stewart

    2011-01-01

    .... A computerized adaptive testing (CAT) simulation was used to evaluate clinical utility. Results The final 43-item pedsPCF item bank demonstrates no item bias, has acceptable IRT parameters, and provides good prediction of related clinical problems...

  2. The Empirical Verification of an Assignment of Items to Subtests : The Oblique Multiple Group Method Versus the Confirmatory Common Factor Method

    NARCIS (Netherlands)

    Stuive, Ilse; Kiers, Henk A.L.; Timmerman, Marieke E.; ten Berge, Jos M.F.

    2008-01-01

    This study compares two confirmatory factor analysis methods on their ability to verify whether correct assignments of items to subtests are supported by the data. The confirmatory common factor (CCF) method is used most often and defines nonzero loadings so that they correspond to the assignment of

  3. Load Balancing Scientific Applications

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, Olga Tkachyshyn [Texas A & M Univ., College Station, TX (United States)

    2014-12-01

    The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

  4. Group differences in the heritability of items and test scores

    Science.gov (United States)

    Wicherts, Jelte M.; Johnson, Wendy

    2009-01-01

    It is important to understand potential sources of group differences in the heritability of intelligence test scores. On the basis of a basic item response model we argue that heritabilities which are based on dichotomous item scores normally do not generalize from one sample to the next. If groups differ in mean ability, the functioning of items at different ability levels may result in group differences in the heritability of items, even when these items function equivalently across groups and the heritability of the underlying ability is equal across groups. We illustrate this graphically, by computer simulation, and by focusing on several problems associated with a recent study by Rushton et al. who argued that the heritability estimates of items of Raven's Progressive Matrices test in North-American twin samples generalized to other population groups, and hence that the population group differences on this test of general mental ability (or intelligence) had a substantial genetic component. Our results show that item heritabilities are strongly dependent on the group on which the heritabilities were based. Rushton et al.'s results were artefactual and do not speak to the nature of population group differences in intelligence test performance. PMID:19403538

  5. Graphical modeling for item difficulty in medical faculty exams.

    Science.gov (United States)

    Tomak, L; Bek, Y; Cengiz, M A

    2016-01-01

    There are different indexes used in the evaluation of exam results. One important index is the difficulty level of the item that is also used in this study to obtain control charts. This article offers some suggestions for the improvement of multiple-choice tests using item analysis statistics. The graphical modeling is important for the rapid and comparative evaluation of test results. The control chart is a tool that can be used to sharpen our teaching and testing skills by inspecting the weaknesses of measurements and producing reliable items. The research data for the application of control charts were obtained using the results of the fourth and fifth-grade student's exams at Ondokuz Mayis University, Faculty of Medicine. I-chart or moving range chart (MR) is preferred for whole variable data. It is seen that all observations are within control limits for I-chart, but three points on MR-chart are settled on the LCL. Using X--chart with subgroups, it was determined that control measurements were within the upper and lower limits in both charts. The difficulty levels of items were examined by obtaining different variable control charts. The difficulty level of the two items exceeded the upper control limit in R- and S-charts. The control charts have the advantage for classifying items as acceptable or unacceptable based on item difficulty criteria.

  6. Bin-packing problems with load balancing and stability constraints

    DEFF Research Database (Denmark)

    Trivella, Alessio; Pisinger, David

    realistic constraints related to e.g. load balancing, cargo stability and weight limits, in the multi-dimensional BPP. The BPP poses additional challenges compared to the CLP due to the supplementary objective of minimizing the number of bins. In particular, in section 2 we discuss how to integrate bin......-packing and load balancing of items. The problem has only been considered in the literature in simplified versions, e.g. balancing a single bin or introducing a feasible region for the barycenter. In section 3 we generalize the problem to handle cargo stability and weight constraints....... is the Container Loading Problem (CLP), which addresses the optimization of a spacial arrangement of cargo inside a container or transportation vehicle, with the objective to maximize the value of the cargo loaded or the volume utilization. The CLP focuses on a single container, and has been extended...

  7. Monitoring Training Load and Fatigue in Rugby Sevens Players

    Science.gov (United States)

    Elloumi, Mohamed; Makni, Emna; Moalla, Wassim; Bouaziz, Taieb; Tabka, Zouhair; Lac, Gérard; Chamari, Karim

    2012-01-01

    Purpose Trainers and physical fitness coaches’ need a useful tool to assess training loads to avoid overtraining. However, perceived scales or questionnaires were required. Therefore, the purpose of this study was to assess whether a short 8-item questionnaire of fatigue could be a useful tool for monitoring changes in perceived training load and strain among elite rugby Sevens (7s) players during preparation for a major competition. Methods Sixteen elite rugby 7s players completed an 8-week training program composed of 6-week intense training (IT) and 2-week reduced training (RT). They were tested before (T0), after the IT (T1) and after the RT (T2). The quantification of the perceived training load and strain were performed by the session-RPE (rating of perceived exertion) method and concomitantly the 8-item questionnaire of fatigue was administered. Results Training load (TL) and strain (TS) and total score of fatigue (TSF from the 8-item questionnaire) increased during IT and decreased during RT. Simultaneously, physical performances decreased during IT and were improved after LT. The changes in TL, TS and TSF correlated significantly over the training period (r=0.63-0.83). Conclusions These findings suggest that the short questionnaire of fatigue could be a practical and a sensitive tool for monitoring changes in training load and strain in team-sport athletes. Accordingly, the simultaneous use of the short questionnaire of fatigue along with the session-RPE method for perceived changes in training load and strain during training could provide additional information on the athletes’ status, allowing coaches to prevent eventual states of overreaching or overtraining. PMID:23012637

  8. 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

  9. Line-item Budgeting and Film-Production

    DEFF Research Database (Denmark)

    Friis, Ivar; Hansen, Allan

    2015-01-01

    conducted a case study on the making of a Danish adventure film and analysed the role budgeting plays from the film director’s point of view. Findings – This paper suggests that the constraints of the line-item budget imposed on the director had positive effects in terms of the pre-commitments entailed...... of line-item budgeting, adding greater insight into the interrelations between creativity and control. By exploring the ways in which line-item budgeting might take on the role of pre-commitment advice and devices in the creative process, this paper further exposes the links between accounting constraints...

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

    Directory of Open Access Journals (Sweden)

    Vanes Mesic

    2011-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Hongmi Lee

    2012-10-01

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

  12. Deconstructing the architecture of alcohol abuse and dependence symptoms in a community sample of late adolescent and emerging adult women: an item response approach.

    Science.gov (United States)

    Duncan, Alexis E; Agrawal, Arpana; Bucholz, Kathleen K; Sartor, Carolyn E; Madden, Pamela A F; Heath, Andrew C

    2011-07-01

    The objective of this study was to examine the underlying factorial architecture of lifetime DSM-IV alcohol use disorder (AUD) criteria in a population-based sample of adolescent and emerging adult female twins who had ever used alcohol (n=2832; aged 18-25 years), and to determine whether thresholds and factor loadings differed by age. Item response modeling was applied to DSM-IV AUD criteria. Compound criteria (e.g., persistent desire or unsuccessful attempts to quit or cut down) were included as separate items. Of the remaining 16 items, tolerance and use despite physical problems were the most and least commonly endorsed items, respectively. Underlying the items was a single factor representing liability to AUDs. Factor loadings ranged from 0.67 for blackouts to 0.90 for time spent using/recovering from effects. Some items assessing different DSM-IV criteria had very similar measurement characteristics, while others assessing the same criterion showed markedly different thresholds and factor loadings. Compared to that of women aged 21-25 years, the threshold for hazardous use was higher in women aged 18-20 years, but lower for used longer than intended and persistent desire to cut down. After accounting for threshold differences, no variations in discrimination across age groups were observed. In agreement with the extant literature, our findings indicate that the factorial structure of AUD is unidimensional, with no support for the abuse/dependence distinction. Individual components of compound criteria may differ in measurement properties; therefore pooling information from such divergent items will reduce information about the AUD construct. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  13. LOADING SIMULATION PROGRAM C

    Data.gov (United States)

    U.S. Environmental Protection Agency — LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for...

  14. Plug Load Data

    Data.gov (United States)

    National Aeronautics and Space Administration — We provide MATLAB binary files (.mat) and comma separated values files of data collected from a pilot study of a plug load management system that allows for the...

  15. LOADING SIMULATION PROGRAM C

    Science.gov (United States)

    LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for simulating hydrology, sediment, and general water quality

  16. HIV Viral Load

    Science.gov (United States)

    ... Chains Sex Hormone Binding Globulin (SHBG) Shiga toxin-producing Escherichia coli Sickle Cell Tests Sirolimus Smooth Muscle ... used each time. Will exercise, nutrition, and other lifestyle modifications help decrease my HIV viral load? There ...

  17. Lumbriculus variegatus loading study

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from sediment bioaccumulation tests with Lumbriculus variegatus with evaluating the effects of organism loading density. This dataset is associated with the...

  18. Static Loads Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides the capability to perform large-scale structural loads testing on spacecraft and other structures. Results from these tests can be used to verify...

  19. Linking Physical and Mental Health Summary Scores from the Veterans RAND 12-Item Health Survey (VR-12) to the PROMIS(®) Global Health Scale.

    Science.gov (United States)

    Schalet, Benjamin D; Rothrock, Nan E; Hays, Ron D; Kazis, Lewis E; Cook, Karon F; Rutsohn, Joshua P; Cella, David

    2015-10-01

    Global health measures represent an attractive option for researchers and clinicians seeking a brief snapshot of a patient's overall perspective on his or her health. Because scores on different global health measures are not comparable, comparative effectiveness research (CER) is challenging. To establish a common reporting metric so that the physical and mental health scores on the Veterans RAND 12-Item Health Survey (VR-12 (©) ) can be converted into scores on the corresponding Patient Reported Outcomes Measurement Information System (PROMIS(®)) Global Health scores. Following a single-sample linking design, participants from an Internet panel completed items from the PROMIS Global Health and VR-12 Health Survey. A common metric was created using analyses based on item response theory (IRT), producing score cross-walk tables for the mental and physical health components of each measure. The linking relationships were evaluated by calculating the standard deviation of differences between the observed and linked PROMIS scores and estimating confidence intervals by sample size. Participants (N = 2025) were 49 % male and 73 % white; mean age was 46 years. Mental and physical health subscales of the PROMIS Global Health and the VR-12. The mean VR-12 physical component and mental component scores were 45.2 and 46.6, respectively; the mean PROMIS physical and mental health scores were 48.3 and 48.5, respectively. We found evidence that the combined set of VR-12 and PROMIS items were relatively unidimensional and that we could proceed with linking. Linking worked better between the physical health than mental health scores using VR-12 item responses (vs. linking based on algorithmic scores). For each of the cross-walks, users can minimize the impact of linking error with modest increases in sample sizes. VR-12 scores can be expressed on the PROMIS Global Health metric to facilitate the evaluation of treatment, including CER. Extending these results to other common

  20. Composite Load Model Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ning; Qiao, Hong (Amy)

    2007-09-30

    The WECC load modeling task force has dedicated its effort in the past few years to develop a composite load model that can represent behaviors of different end-user components. The modeling structure of the composite load model is recommended by the WECC load modeling task force. GE Energy has implemented this composite load model with a new function CMPLDW in its power system simulation software package, PSLF. For the last several years, Bonneville Power Administration (BPA) has taken the lead and collaborated with GE Energy to develop the new composite load model. Pacific Northwest National Laboratory (PNNL) and BPA joint force and conducted the evaluation of the CMPLDW and test its parameter settings to make sure that: • the model initializes properly, • all the parameter settings are functioning, and • the simulation results are as expected. The PNNL effort focused on testing the CMPLDW in a 4-bus system. An exhaustive testing on each parameter setting has been performed to guarantee each setting works. This report is a summary of the PNNL testing results and conclusions.

  1. 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.

  2. Load power device, system and method of load control and management employing load identification

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yi; Luebke, Charles John; Schoepf, Thomas J.

    2018-01-09

    A load power device includes a power input, at least one power output for at least one load, a plurality of sensors structured to sense voltage and current at the at least one power output, and a processor. The processor provides: (a) load identification based upon the sensed voltage and current, and (b) load control and management based upon the load identification.

  3. 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.

  4. Can the Focus of Attention Accommodate Multiple, Separate Items?

    Science.gov (United States)

    Gilchrist, Amanda L.; Cowan, Nelson

    2011-01-01

    Researchers of working memory currently debate capacity limits of the focus of attention, the proposed mental faculty in which items are most easily accessed. Cowan (1999) suggested that its capacity is about 4 chunks, whereas others have suggested that its capacity is only 1 chunk. Recently, Oberauer and Bialkova (2009) found evidence that 2 items could reside in the focus of attention, but only because they were combined into a single chunk. We modified their experimental procedure, which depends on a pattern of switch costs, to obtain a situation in which chunking was not likely to occur (i.e., each item remained a separate chunk), and still obtained results consistent with a capacity of at least 2 items. Therefore, either the focus of attention can hold multiple chunks, or the switch cost logic must be reconsidered. PMID:21767065

  5. Etendatakse 10-aastase kirjamehe näitemäng

    Index Scriptorium Estoniae

    2003-01-01

    Tartu katoliku kooli 3. klassi poisi Mario Raitari näitemäng "Kristoph Silvester von Tenderi lugu", mis on esimene lugu sarjast "Mario Raitari kroonika". Näidendit etendab Linnupuu Lastepereteatri trupp

  6. 75 FR 6795 - Designation of Biobased Items for Federal Procurement

    Science.gov (United States)

    2010-02-10

    ... procurement preference: Disposable tableware; expanded polystyrene foam recycling products; heat transfer... following items for preferred procurement: Disposable tableware; expanded polystyrene (EPS) foam recycling... (``expandable polystyrene foam recycling products'') is based on a single tested product. Given that only two...

  7. Modular Open-Source Software for Item Factor Analysis.

    Science.gov (United States)

    Pritikin, Joshua N; Hunter, Micheal D; Boker, Steven

    2015-06-01

    This paper introduces an Item Factor Analysis (IFA) module for OpenMx, a free, open-source, and modular statistical modeling package that runs within the R programming environment on GNU/Linux, Mac OS X, and Microsoft Windows. The IFA module offers a novel model specification language that is well suited to programmatic generation and manipulation of models. Modular organization of the source code facilitates the easy addition of item models, item parameter estimation algorithms, optimizers, test scoring algorithms, and fit diagnostics all within an integrated framework. Three short example scripts are presented for fitting item parameters, latent distribution parameters, and a multiple group model. The availability of both IFA and structural equation modeling in the same software is a step toward the unification of these two methodologies.

  8. Bayesian longitudinal item response modeling with restricted covariance pattern structures

    NARCIS (Netherlands)

    Azevedo, Caio L.N.; Fox, Gerardus J.A.; Andrade, Dalton F.

    2016-01-01

    Educational studies are often focused on growth in student performance and background variables that can explain developmental differences across examinees. To study educational progress, a flexible latent variable model is required to model individual differences in growth given longitudinal item

  9. 17 CFR 229.1111 - (Item 1111) Pool assets.

    Science.gov (United States)

    2010-04-01

    ... AND CONSERVATION ACT OF 1975-REGULATION S-K Asset-Backed Securities (Regulation AB) § 229.1111 (Item.... (vi) Finance charges, fees and other income earned. (vii) Balance reductions granted for refunds...

  10. Calibration of the Spanish PROMIS Smoking Item Banks

    Science.gov (United States)

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

    2016-01-01

    Introduction: The Patient-Reported Outcomes Measurement Information System (PROMIS) Smoking Initiative has developed item banks for assessing six smoking behaviors and biopsychosocial correlates of smoking among adult cigarette smokers. The goal of this study is to evaluate the performance of the Spanish version of the PROMIS smoking item banks as compared to the original banks developed in English. Methods: The six PROMIS banks for daily smokers were translated into Spanish and administered to a sample of Spanish-speaking adult daily smokers in the United States (N = 302). We first evaluated the unidimensionality of each bank using confirmatory factor analysis. We then conducted a two-group item response theory calibration, including an item response theory-based Differential Item Functioning (DIF) analysis by language of administration (Spanish vs. English). Finally, we generated full bank and short form scores for the translated banks and evaluated their psychometric performance. Results: Unidimensionality of the Spanish smoking item banks was supported by confirmatory factor analysis results. Out of a total of 109 items that were evaluated for language DIF, seven items in three of the six banks were identified as having levels of DIF that exceeded an established criterion. The psychometric performance of the Spanish daily smoker banks is largely comparable to that of the English versions. Conclusions: The Spanish PROMIS smoking item banks are highly similar, but not entirely equivalent, to the original English versions. The parameters from these two-group calibrations can be used to generate comparable bank scores across the two language versions. Implications: In this study, we developed a Spanish version of the PROMIS smoking toolkit, which was originally designed and developed for English speakers. With the growing Spanish-speaking population, it is important to make the toolkit more accessible by translating the items and calibrating the Spanish version to

  11. Development of six PROMIS pediatrics proxy-report item banks

    Directory of Open Access Journals (Sweden)

    Irwin Debra E

    2012-02-01

    Full Text Available Abstract Background 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. Methods 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. Results 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

  12. Calibration of the Spanish PROMIS Smoking Item Banks.

    Science.gov (United States)

    Huang, Wenjing; Stucky, Brian D; Edelen, Maria O; Tucker, Joan S; Shadel, William G; Hansen, Mark; Cai, Li

    2016-07-01

    The Patient-Reported Outcomes Measurement Information System (PROMIS) Smoking Initiative has developed item banks for assessing six smoking behaviors and biopsychosocial correlates of smoking among adult cigarette smokers. The goal of this study is to evaluate the performance of the Spanish version of the PROMIS smoking item banks as compared to the original banks developed in English. The six PROMIS banks for daily smokers were translated into Spanish and administered to a sample of Spanish-speaking adult daily smokers in the United States (N = 302). We first evaluated the unidimensionality of each bank using confirmatory factor analysis. We then conducted a two-group item response theory calibration, including an item response theory-based Differential Item Functioning (DIF) analysis by language of administration (Spanish vs. English). Finally, we generated full bank and short form scores for the translated banks and evaluated their psychometric performance. Unidimensionality of the Spanish smoking item banks was supported by confirmatory factor analysis results. Out of a total of 109 items that were evaluated for language DIF, seven items in three of the six banks were identified as having levels of DIF that exceeded an established criterion. The psychometric performance of the Spanish daily smoker banks is largely comparable to that of the English versions. The Spanish PROMIS smoking item banks are highly similar, but not entirely equivalent, to the original English versions. The parameters from these two-group calibrations can be used to generate comparable bank scores across the two language versions. In this study, we developed a Spanish version of the PROMIS smoking toolkit, which was originally designed and developed for English speakers. With the growing Spanish-speaking population, it is important to make the toolkit more accessible by translating the items and calibrating the Spanish version to be comparable with English-language scores. This study

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

    OpenAIRE

    Andi Ulfa Tenri Pada; Badrun Kartowagiran; Bambang Subali

    2016-01-01

    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 analyze...

  14. Analysis of Frequent Item set Mining on Variant Datasets

    OpenAIRE

    Henry Alexander; Rohit Bansal; Robin Singh Bhadoria

    2011-01-01

    Association rule mining is the process of discovering relationships among the data items in large database. It is one of the most important problems in the field of data mining. Finding frequent itemsets is one of the most computationally expensive tasks in association rule mining. The classical frequent itemset mining approaches mine the frequent itemsets from the database where presence of an item in a transaction is certain. Frequent itemset mining under uncertain data model is a new area ...

  15. Learning Item Trees for Probabilistic Modelling of Implicit Feedback

    OpenAIRE

    Mnih, Andriy; Teh, Yee Whye

    2011-01-01

    User preferences for items can be inferred from either explicit feedback, such as item ratings, or implicit feedback, such as rental histories. Research in collaborative filtering has concentrated on explicit feedback, resulting in the development of accurate and scalable models. However, since explicit feedback is often difficult to collect it is important to develop effective models that take advantage of the more widely available implicit feedback. We introduce a probabilistic approach to ...

  16. A Rasch Analysis of Grammatical Difficulty : What Influences Item Difficulty?

    OpenAIRE

    Atsuko, Nishitani; Kyoto Sangyo University

    2014-01-01

    This study investigated the difficulty order of 38 grammar structures obtained from an analysis of multiple-choice items using a Rasch analysis. The participants were 872 Japanese university students, whose TOEIC scores ranged from 200 to 875. The difficulty order of the 38 structures was displayed according to their Rasch difficulty estimates. This study also demonstrated the difficulty of writing items testing the knowledge of the same grammar point that show similar Rasch difficulty estima...

  17. Item response analysis of the inventory of depressive symptomatology

    OpenAIRE

    Bernstein, Ira H; Rush, A John; Carmody, Thomas J; Woo, Ada; Trivedi, Madhukar H

    2006-01-01

    Background: Both the clinician (IDS-C30) and self-report (IDS-SR30) versions of the 30-item Inventory of Depressive Symptomatology have acceptable psychiatric properties and have been used in various clinical studies. These two scales, however, have not been compared using item response theory (IRT) methods to determine whether the standard scoring methods are optimal. Methods: Data were derived from 428 adult public sector outpatients with nonpsychotic major depressive disorder. The IDS-C30 ...

  18. MMPI-2 Item Endorsements in Dissociative Identity Disorder vs. Simulators.

    Science.gov (United States)

    Brand, Bethany L; Chasson, Gregory S; Palermo, Cori A; Donato, Frank M; Rhodes, Kyle P; Voorhees, Emily F

    2016-03-01

    Elevated scores on some MMPI-2 (Minnesota Multiphasic Inventory-2) validity scales are common among patients with dissociative identity disorder (DID), which raises questions about the validity of their responses. Such patients show elevated scores on atypical answers (F), F-psychopathology (Fp), atypical answers in the second half of the test (FB), schizophrenia (Sc), and depression (D) scales, with Fp showing the greatest utility in distinguishing them from coached and uncoached DID simulators. In the current study, we investigated the items on the MMPI-2 F, Fp, FB, Sc, and D scales that were most and least commonly endorsed by participants with DID in our 2014 study and compared these responses with those of coached and uncoached DID simulators. The comparisons revealed that patients with DID most frequently endorsed items related to dissociation, trauma, depression, fearfulness, conflict within family, and self-destructiveness. The coached group more successfully imitated item endorsements of the DID group than did the uncoached group. However, both simulating groups, especially the uncoached group, frequently endorsed items that were uncommonly endorsed by the DID group. The uncoached group endorsed items consistent with popular media portrayals of people with DID being violent, delusional, and unlawful. These results suggest that item endorsement patterns can provide useful information to clinicians making determinations about whether an individual is presenting with DID or feigning. © 2016 American Academy of Psychiatry and the Law.

  19. Promoting cold-start items in recommender systems.

    Science.gov (United States)

    Liu, Jin-Hu; Zhou, Tao; Zhang, Zi-Ke; Yang, Zimo; Liu, Chuang; Li, Wei-Min

    2014-01-01

    As one of the major challenges, cold-start problem plagues nearly all recommender systems. In particular, new items will be overlooked, impeding the development of new products online. Given limited resources, how to utilize the knowledge of recommender systems and design efficient marketing strategy for new items is extremely important. In this paper, we convert this ticklish issue into a clear mathematical problem based on a bipartite network representation. Under the most widely used algorithm in real e-commerce recommender systems, the so-called item-based collaborative filtering, we show that to simply push new items to active users is not a good strategy. Interestingly, experiments on real recommender systems indicate that to connect new items with some less active users will statistically yield better performance, namely, these new items will have more chance to appear in other users' recommendation lists. Further analysis suggests that the disassortative nature of recommender systems contributes to such observation. In a word, getting in-depth understanding on recommender systems could pave the way for the owners to popularize their cold-start products with low costs.

  20. Promoting Cold-Start Items in Recommender Systems

    Science.gov (United States)

    Liu, Jin-Hu; Zhou, Tao; Zhang, Zi-Ke; Yang, Zimo; Liu, Chuang; Li, Wei-Min

    2014-01-01

    As one of the major challenges, cold-start problem plagues nearly all recommender systems. In particular, new items will be overlooked, impeding the development of new products online. Given limited resources, how to utilize the knowledge of recommender systems and design efficient marketing strategy for new items is extremely important. In this paper, we convert this ticklish issue into a clear mathematical problem based on a bipartite network representation. Under the most widely used algorithm in real e-commerce recommender systems, the so-called item-based collaborative filtering, we show that to simply push new items to active users is not a good strategy. Interestingly, experiments on real recommender systems indicate that to connect new items with some less active users will statistically yield better performance, namely, these new items will have more chance to appear in other users' recommendation lists. Further analysis suggests that the disassortative nature of recommender systems contributes to such observation. In a word, getting in-depth understanding on recommender systems could pave the way for the owners to popularize their cold-start products with low costs. PMID:25479013