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Rasch Analysis (rasch + analysis)
Selected AbstractsShortened questionnaire on quality of life for inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 4 2004M. J. Alcalá MD Abstract Questionnaires for measuring quality of life in patients with inflammatory bowel disease usually include a large number of items and are time-consuming for both administration and interpretation. Our aim was to elaborate and validate a short quality-of-life questionnaire with the most representative items from the Spanish version of the 36-item Inflammatory Bowel Disease Questionnaire (IBDQ-36) using the Rasch analysis. The responses to 311 IBDQ-36 questionnaires from 167 patients with ulcerative colitis (UC) and 144 with Crohn's disease (CD) were analyzed. IBDQ-36 was shortened with successive Rasch analyses until all the remaining items showed acceptable separation and goodness-of-fit properties. Validation of the short questionnaire was studied in a new group of 125 patients by determining its validity and reliability. A 9-item short questionnaire was obtained (IBDQ-9). Its correlation with IBDQ-36 was excellent (r = 0.91). Correlation between IBDQ-9 and clinical indices of activity was statistically significant in UC (r = 0.70) and CD (r = 0.70). IBDQ-9 score discriminates adequately between patients in clinical remission or relapse (P < 0.01). Sensitivity to change was determined in 14 patients who improved clinically, showing significant IBDQ-9 changes between both determinations (P < 0.01), with an effect size of ,2.67 in UC and ,5.29 in CD. IBDQ-9 was also homogeneous, with a Cronbach's , of 0.95 in UC and 0.91 in CD. In 35-clinically stable patients, test-retest reliability was good, with a statistically-significant correlation between both questionnaires (r = 0.76 in UC and 0.86 in CD, P < 0.01) and an intraclass correlation coefficient of 0.82 in UC and 0.84 in CD. In conclusion, a short and valid questionnaire to measure quality of life in patients with inflammatory bowel disease was obtained using a new measurement model. Its use should facilitate comprehension of the impact of inflammatory bowel disease. [source] Assessing autonomic symptoms of Parkinson's disease with the SCOPA-AUT: a new perspective from Rasch analysisEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2010M. J. Forjaz Background:, The Scale for Outcomes in Parkinson's disease (PD) for Autonomic Symptoms (SCOPA-AUT) is a specific scale to assess autonomic dysfunction in PD patients. It was developed and validated under the classic test theory approach. This study sought to test whether the SCOPA-AUT meets item response theory standards for reliability, internal construct validity, response category ordering, and differential item functioning by gender and age group. Method:, The Rasch measurement model was applied to a sample of 385 PD patients. Results:, Model fit was obtained after the response categories were rescored and item 10-Incomplete emptying deleted because of redundancy. Person separation index, a reliability measure, was 0.82. All but two items (2-Sialorrhea and 13-Nocturia) were free of gender- and age-related bias. The strict tests of unidimensionality were met, indicating the validity of the total sumscore. Scale targeting suggested the need for items representing milder autonomic symptoms. Conclusions:, Suggestions for improving the SCOPA-AUT include a shorter scale with a simpler response scheme and a combination of sexual items for men and women. The resulting SCOPA-AUT is a reliable scale, with good internal construct validity, providing Rasch transformed results on a linear metric scale. [source] Assessments of learning-related skills and interpersonal skills constructs within early childhood environments in SingaporeINFANT AND CHILD DEVELOPMENT, Issue 4 2010Sok Mui Lim Abstract Social skills are necessary for developing successful relationships and promoting learning. Interpersonal skills (IPS) are needed for maintaining friendships while learning-related skills (LRS) are required for positive classroom behaviours. In this study, we investigated the construct validity of LRS and IPS within two existing assessments: the Child Behavior Rating Scales (CBRS) and the Preschool and Kindergarten Behavior Scales,2nd edition (PKBS-2). Teachers completed the CBRS and PKBS-2 for 117 Singaporean children aged 3,6 years. Rasch analysis was used to identify items that fit the unidimensional constructs of LRS and IPS within each instrument. Specific items from within the CBRS were found to measure LRS and IPS. Within the PKBS-2, items were found to measure IPS and a new construct labelled Compliance. Instead of creating new assessment tools to measure new constructs, this study innovatively demonstrated how Rasch analysis can be used to document the existence of new constructs within already existing tools. The identification of new constucts and the use of these tools in an Asian context are presented. Copyright © 2010 John Wiley & Sons, Ltd. [source] Shortened questionnaire on quality of life for inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 4 2004M. J. Alcalá MD Abstract Questionnaires for measuring quality of life in patients with inflammatory bowel disease usually include a large number of items and are time-consuming for both administration and interpretation. Our aim was to elaborate and validate a short quality-of-life questionnaire with the most representative items from the Spanish version of the 36-item Inflammatory Bowel Disease Questionnaire (IBDQ-36) using the Rasch analysis. The responses to 311 IBDQ-36 questionnaires from 167 patients with ulcerative colitis (UC) and 144 with Crohn's disease (CD) were analyzed. IBDQ-36 was shortened with successive Rasch analyses until all the remaining items showed acceptable separation and goodness-of-fit properties. Validation of the short questionnaire was studied in a new group of 125 patients by determining its validity and reliability. A 9-item short questionnaire was obtained (IBDQ-9). Its correlation with IBDQ-36 was excellent (r = 0.91). Correlation between IBDQ-9 and clinical indices of activity was statistically significant in UC (r = 0.70) and CD (r = 0.70). IBDQ-9 score discriminates adequately between patients in clinical remission or relapse (P < 0.01). Sensitivity to change was determined in 14 patients who improved clinically, showing significant IBDQ-9 changes between both determinations (P < 0.01), with an effect size of ,2.67 in UC and ,5.29 in CD. IBDQ-9 was also homogeneous, with a Cronbach's , of 0.95 in UC and 0.91 in CD. In 35-clinically stable patients, test-retest reliability was good, with a statistically-significant correlation between both questionnaires (r = 0.76 in UC and 0.86 in CD, P < 0.01) and an intraclass correlation coefficient of 0.82 in UC and 0.84 in CD. In conclusion, a short and valid questionnaire to measure quality of life in patients with inflammatory bowel disease was obtained using a new measurement model. Its use should facilitate comprehension of the impact of inflammatory bowel disease. [source] Three sides of the same coin: measuring global cognitive impairment with the MMSE, ADAS-cog and CAMCOGINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2010Hans Wouters Abstract Objective The total scores of the ADAS-cog, MMSE and CAMCOG, comprising various cognitive tasks, are widely used to measure a dimension of global cognitive impairment. It is unknown, however, whether this dimension is common to these instruments. This hampers comparisons when either of these instruments is used. The extent to which these instruments share a common dimension of global cognitive impairment and how their scores relate was examined. Methods Rasch analysis of CAMCOG and MMSE data of participants from a population based study and two memory clinics pooled with ADAS-cog and MMSE data of participants from three RCTs (overall N,=,1566) to estimate a common dimension of global cognitive impairment and to examine the goodness of fit of the individual items to this dimension. Results Using the estimated common dimension of global cognitive impairment, the total scores of the instruments could be related, e.g. a mean level of global cognitive impairment corresponded to a predicted score of 11.4 (ADAS-cog), 72.6 (CAMCOG) and 22.2 (MMSE). When revised according to The Rasch validity analyses, every individual item could be fitted to the dimension. Conclusions The MMSE, ADAS-cog and CAMCOG reflect a valid common dimension of global cognitive impairment, which enables comparisons of RCTs that use the ADAS-cog and observational studies that use the CAMCOG and MMSE. Copyright © 2009 John Wiley & Sons, Ltd. [source] The Stability of Rater Severity in Large-Scale Assessment ProgramsJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 2 2000Peter J. Congdon The purpose of this study was to investigate the stability of rater severity over an extended rating period. Multifaceted Rasch analysis was applied to ratings of 16 raters on writing performances of 8, 285 elementary school students. Each performance was rated by two trained raters over a period of seven rating days. Performances rated on the first day were re-rated at the end of the rating period. Statistically significant differences between raters were found within each day and in all days combined. Daily estimates of the relative severity of individual raters were found to differ significantly from single, on-average estimates for the whole rating period. For 10 raters, severity estimates on the last day were significantly different from estimates on the first day. These fndings cast doubt on the practice of using a single calibration of rater severity as the basis for adjustment of person measures. [source] Exploring alternative conceptions from Newtonian dynamics and simple DC circuits: Links between item difficulty and item confidenceJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 2 2006Maja Planinic Croatian 1st-year and 3rd-year high-school students (N,=,170) completed a conceptual physics test. Students were evaluated with regard to two physics topics: Newtonian dynamics and simple DC circuits. Students answered test items and also indicated their confidence in each answer. Rasch analysis facilitated the calculation of three linear measures: (a) an item-difficulty measure based upon all responses, (b) an item-confidence measure based upon correct student answers, and (c) an item-confidence measure based upon incorrect student answers. Comparisons were made with regard to item difficulty and item confidence. The results suggest that Newtonian dynamics is a topic with stronger students' alternative conceptions than the topic of DC circuits, which is characterized by much lower students' confidence on both correct and incorrect answers. A systematic and significant difference between mean student confidence on Newtonian dynamics and DC circuits items was found in both student groups. Findings suggest some steps for physics instruction in Croatia as well as areas of further research for those in science education interested in additional techniques of exploring alternative conceptions. © 2005 Wiley Periodicals, Inc. J Res Sci Teach 43: 150,171, 2006 [source] More than smile sheets: Rasch analysis of training reactions in a medical centerPERFORMANCE IMPROVEMENT QUARTERLY, Issue 3 2009Daniel McLinden EdD Reaction questionnaires administered at the conclusion of a training program are a common method of evaluation. Because such questionnaires are often constructed and analyzed in an ad hoc manner, their usefulness is often difficult to gauge. However, if properly constructed and analyzed, such instruments can help to make clear the strengths and weaknesses of programs. This article presents a framework for questionnaire development and analysis to ensure that such questionnaires are psychometrically sound and useful for decision making. The data used for this research were from over 5,000 questionnaires completed by individuals at the conclusion of educational programs. The Rasch model was used to evaluate the data. Results suggest that the posttraining questionnaire is a valid and reliable indicator of program quality. In addition, the Rasch analysis provided empirically based methods for diagnosing needed improvements to assessment instruments. [source] The use of the comprehensive International Classification of Functioning, Disability and Health Core Set for low back pain in clinical practice: a reliability studyPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 3 2009Roger Hilfiker Abstract Background and Purpose.,The comprehensive International Classification of Functioning, Disability and Health (ICF) Core Set for low back pain (LBP) can be used to describe functioning and the influence of the environment of patients with LBP with a selection of 78 categories, from the ICF components ,body functions', ,body structures', ,activities and participation' and ,environmental factors'. The reliability of the qualifiers' scale of the ICF Core Set for LBP has not yet been studied.,Methods.,Reliability study was conducted in three study centres in the German-speaking part of Switzerland. In the first step, two physiotherapists independently assessed 31 patients with LBP with the original qualifier scale of the 78 ICF categories from the comprehensive ICF Core Set for LBP. After the first 31 patients, inter-rater reliability was assessed and the response options were reduced based on a Rasch analysis. The second sample (n = 30) was assessed by the physiotherapists with the modified qualifier scale and inter-rater reliability was calculated again.,Results.,The percentage agreement for the ICF categories ranged from 19% to 87%, mean 44% (nominal kappa from ,0.73 to 0.54, median 0.22; weighted kappa ,0.2 to 0.69, median 0.38) in the first round with the original qualifier scale. In the second round with the reduced response options, the percentage agreement ranged from 23% to 90%, mean 49% (nominal kappa from ,0.15 to 0.71, median 0.24; weighted kappa ,0.16 to 0.81, median 0.25). The overall percentage agreement was 44% in the first round and 49% with the reduced response categories. The overall kappa value in the first round was 0.29 and in the second round 0.32. There was a small but statistically significant improvement in the agreement.,Conclusion.,The low-to-moderate reliability found in this study requires an improved operationalization (e.g. the definition and description of each response category) and improved instructions for the ICF Core Set for LBP. Copyright © 2009 John Wiley & Sons, Ltd. [source] Assessment of the upper limb in acute stroke: The validity of hierarchal scoring for the Motor Assessment ScaleAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 3 2010Rebekah L. Pickering Background/aim:, Stroke is the greatest contributor to disability in Australian adults and much of this disability results from a stroke-affected upper limb. This study aimed to determine the validity of hierarchal scoring for the upper limb subscale of the Motor Assessment Scale (UL-MAS) in acute stroke using Rasch analysis. Method:, This study applied Rasch analysis to 40 UL-MAS assessment results across 25 subjects to determine the validity of the hierarchy of the three upper limb subsets: upper arm function (six), hand movements (seven) and advanced hand activities (eight). Rasch analysis examines the relationship between ,item difficulty' and ,person ability' and produces an output which represents the difficulty of each item in relation to each other. Results:, As hypothesised, the hierarchy was upheld within subset 6. In subset 7, the hierarchy was not upheld. Results indicated that item 3 was the least difficult, followed by items 1, 4, 2, 5 and 6 in order of increasing difficulty. In subset 8 the hierarchy was not upheld. Results indicated that item 1 was the least difficult, followed by item 6, then 2 and 5 of equal value and then 3 and 4 of equal value. Conclusions:, The hierarchal scoring is not supported for subsets 7 and 8 and future research is required to explore the validity of alternate scoring methods. At present, the authors recommend that the UL-MAS should be scored non-hierarchally, meaning that every item within the subsets should be scored regardless of its place within the hierarchy (UL-MAS-NH). [source] Assessment of functional vision and its rehabilitationACTA OPHTHALMOLOGICA, Issue 2 2010August Colenbrander Abstract. This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time-consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow. [source] Efficient assessment of social problem-solving abilities in medical and rehabilitation settings: a rasch analysis of the social problem-solving inventory-revisedJOURNAL OF CLINICAL PSYCHOLOGY, Issue 7 2009Laura E. Dreer Abstract The Social Problem Solving Inventory-Revised Scale (SPSI-R) has been shown to be a reliable and valid self-report measure of social problem-solving abilities. In busy medical and rehabilitation settings, a brief and efficient screening version with psychometric properties similar to the SPSI-R would have numerous benefits including decreased patient and caregiver assessment burden and administration/scoring time. Thus, the aim of the current study was to identify items from the SPSI-R that would provide for a more efficient assessment of global social problem-solving abilities. This study consisted of three independent samples: 121 persons in low-vision rehabilitation (M age=71 years old, SD=15.53), 301 persons living with diabetes mellitus (M age=58, and SD=14.85), and 131 family caregivers of persons with severe disabilities (M age=56 years old, SD=12.15). All persons completed a version of the SPSI-R, Center for Epidemiological Studies Depression Scale (CES-D), and the Satisfaction with Life Scale (SWLS). Using Rasch scaling of the SPSI-R short-form, we identified a subset of 10 items that reflected the five-component model of social problem solving. The 10 items were separately validated on the sample of persons living with diabetes mellitus and the sample of family caregivers of persons with severe disabilities. Results indicate that the efficient 10-item version, analyzed separately for all three samples, demonstrated good reliability and validity characteristics similar to the established SPSI-R short form. The 10-item version of the SPSI-R represents a brief, effective way in which clinicians and researchers in busy health care settings can quickly assess global problem-solving abilities and identify those persons at-risk for complicated adjustment. Implications for the assessment of social problem-solving abilities are discussed. © 2009 Wiley Periodicals, Inc. J Clin Psychol 65: 1,15, 2009. [source] |