Response Category Functioning Research Articles

Development and Validation of the Youth Back Activity Questionnaire: A Measure of Function for Adolescents with Low Back Pain.

Psychometric study. To develop a reliable and valid patient-reported outcome measure to assess functional ability in adolescents with low back pain (LBP) using the Rasch model. LBP is quite common in adolescence. Currently, no method adequately measures the functional ability of adolescents with LBP. Widely used outcome measures for LBP are problematic in adolescents, with significant ceiling/floor effects. Two hundred adolescents (15.4 ± 1.9 years; 56% female) with LBP. This study was comprised of two parts: Part 1: Development of the Youth Back Activity Questionnaire (YouthBAQ) (n = 75), and Part 2: Psychometric evaluation of the newly designed YouthBAQ using the Rasch Model (n = 125). Participants also completed the Oswestry Disability Index (ODI) and Micheli Functional Scale (MFS), Data Analysis: Reliability and construct validity of the YouthBAQ were assessed using Rasch analyses. Correlations with the ODI and MFS were used to determine the convergent validity of the YouthBAQ. Part 1: Based on the results of the Rasch analysis, 31 items were reduced to 14. Part 2. The 14-item YouthBAQ demonstrated good reliability and construct validity, with good item fit (>0.7 and <1.3), acceptable item hierarchy and spacing, response category functioning, unidimensionality (ratio >3:1), local independence (<0.30). The MFS demonstrated unacceptable reliability (person reliability = 0.62) and was not compared against the YouthBAQ. The ODI demonstrated acceptable reliability (person reliability =0.70), but poor construct validity among adolescents with LBP. The YouthBAQ demonstrated a moderate correlation with the ODI (r = 0.4). The YouthBAQ is a quick and easily understood measure of function with good validity and reliability in adolescents with LBP. The YouthBAQ is a more appropriate measure of functional ability than the ODI or MFS in this population.

Development and validation of the 5-Dimension Comprehensive Assessment Scale (5DCAS) for assessing physical function and health in axial spondyloarthritis.

To describe the development and validation of a novel patient reported scale, which is a comprehensive assessment of the physical function and health specific for patients with axial spondyloarthritis (axSpA). This is a multiphase, mixed methods study. Based on opinion collection and discussions of multidisciplinary consensus meetings and patients, an initial item pool covering all of the ranges of functioning was generated. The item optimization, model fit, response category functioning, differential item functioning, reliability, structure validity, and unidimensionality were tested by confirmatory factor analysis and Rasch measurement theory framework. After the consensus meeting and the two rounds of surveys in patients with axSpA, the initial pool of 135 items was reduced to 25 items formed in five dimensions, which exhibited preferable item reliability, item fit, and person fit to the Rasch model. The Five-Dimensional Comprehensive Assessment Scale (5DCAS) had the best reliability and validity (Kaiser-Meyer-Olkin was 0.919, and the standardized Cronbach's α coefficient was 0.932). The final version of 5DCAS had good unidimensionality, and the Person Separation Index ranged from 0.77 to 0.85. 5DCAS significantly correlated with ASAS-HI, SF-36, BASFI, and disease activity with p values of < 0.001. 5DCAS is a novel patient-reported outcome specific to axSpA, and it forms five dimensions providing a linear sum score of 25 items. 5DCAS comprehensively and significantly represents the physical function and health status of patients with axSpA, although its performance needs further validation in future clinical practices. Key Points • The primary goal in the management of axial spondyloarthritis is to maximize health-related quality of life. Except for the current instruments of ASAS-HI, BASFI, or SF-36, the heterogeneous clinical symptoms and rapid updated treat-to-target concept require a new instrument which can comprehensive and significant evaluate the changes of physical function and health-related quality of life due to disease. • 5DCAS is a novel patient-reported outcome specific to axSpA, and it forms five dimensions providing a linear sum score of 25 items, which contained aspect of pain involvement, spine mobility, global body performance and activity, social participation and environment, and mental health. All of the items were set to a 4-point semantic rating scale measuring severity, frequency, or interference from score 0 to 3. Total 5DCAS score ranges from 0 to 75; higher scores represented greater symptom burden and worse physical function. • 5DCAS is a comprehensive, multidisciplinary, and convenient disease outcome measurement specific for axSpA. It provides a new evaluation instrument in clinical trial and treat-to-target clinical remission for patients and physicians, and also provides a sensitive and accurate assessment standard for optimized health benefits.

Development and quality assessment of the psychometric properties of the Self-Efficacy in Lifestyle Counselling scale (SELC 20 + 20) using Rasch analysis

BackgroundGlobally as well as in Sweden, diseases that are caused by unhealthy lifestyle habits are the most common causes of death and disability. Even though there are guidelines that oblige all health-care professionals to counsel patients about lifestyle, studies have shown that it is not prioritized within healthcare. One reason for this among nurses has been shown to be lack of confidence in knowledge and counselling skills. This study aimed to develop, and quality assess the psychometric properties of an instrument to measure self-efficacy in lifestyle counselling.MethodsAn instrument inspired by an American instrument, following Bandura’s recommendations for development of self-efficacy measures, was developed according to Swedish national guidelines for disease-prevention. The instrument was revised after cognitive interviews with nursing students, university teachers within health sciences, and clinical experts, then administrated to 310 nursing students at different levels in their education. The instrument was tested with Rasch Measurement Theory, with focus on dimensionality, local dependency, targeting, reliability, response category functioning, Rasch model fit, and differential item functioning by age, gender, educational level and previous health care education.ResultsThe development of the instrument resulted in 20 + 20 items, 20 items about self-efficacy in knowledge, and 20 items about self-efficacy in ability to counsel persons about their lifestyle. The analyses showed that knowledge and ability are two different, but related, constructs, where ability is more demanding than knowledge. The findings provide support (considering dimensionality and local dependency) for that all 20 items within the knowledge construct as well as the 20 items within the ability construct can be summed, achieving two separate but related total scores, where knowledge (reliability 0.81) is a prerequisite for ability (reliability 0.84). Items represented lower self-efficacy than reported by the respondents. Response categories functioned as expected, Rasch model fit was acceptable, and there was no differential item functioning.ConclusionsThe SELC 20 + 20 was found to be easy to understand with an acceptable respondent burden and the instrument showed good measurement properties.

Validation of a Sejahtera Living Index Using the Rasch Model

The Maqāṣid al-Sharī’ah is a framework of divine values and beliefs that govern the life of a Muslim person. It contains clear guidelines on how to live the good life the way the religion sees it and on what constitutes quality of life, happiness, and wellbeing for the Muslim. In more precise terms, the maqāṣid al-sharī’ah guides Muslim in regard to how they can achieve a sejahtera life. Although sejahtera living is a fundamental and a highly important concept, it is not widely researched or addressed in the current body of empirical literature. One can see that there is a paucity of empirical data on sejahtera living. To address this research gap, this study first developed a scale to measure sejahtera living and subsequently examined its validity. It also estimated the index scores of sejahtera living among students and employees of a public university in Malaysia. This paper reports on the findings of this validation exercise which involved a sample 1,057 lecturers, nonacademic staff, and postgraduate and undergraduate students. Data were collected using a content validated 34-item questionnaire created based on the dimensions of the maqāṣid al-sharī’ah. The results of the Rasch measurement analysis provided evidence for the validity of the sejahtera living construct in terms of the good fit of the items, reliability and separation indexes, response category functioning, dimensionality, and construct validity. The extracted logit interval scores were used to construct linear measures of the baseline sejahtera living index. The findings support the need for instructional interventions and training to sustain and improve the quality of sejahtera living among Muslims.

Measurement properties of the Falls Efficacy Scale-International (FES-I) in persons with late effects of polio: A cross-sectional study.

Fear of falling (FoF) is very common in persons with late effects of polio (LEoP). An internationally recognized rating scale to assess FoF is the Falls Efficacy Scale-International (FES-I). Yet, there is limited knowledge about its measurement properties in persons with LEoP. To investigate the measurement properties of the FES-I (16-item version) and the short FES-I (7-item version) in persons with LEoP. Explorative factor analysis and Rasch model analysis of cross-sectional data. University hospital. A total of 321 persons with LEoP (mean age ± standard deviation [SD] 70 ± 10 years, 173 women). The FES-I and the short FES-I, comprising four response options about concerns of falling ranging from 1 (not at all concerned) to 4 (very concerned). Data were collected by a postal survey. First, a factor analysis was performed to investigate the unidimensionality of the scale. Thereafter, a Rasch model analysis was used to further analyze the measurement properties of the FES-I and the short FES-I, such as local dependency, targeting, hierarchical order of items, Differential Item Functioning (DIF), response category functioning and reliability (Person Separation Index, PSI). Raw score transformation to interval measurements was also performed. The factor analysis revealed that the FES-I was unidimensional, even though the Rasch analysis showed some misfit to the Rasch model and local dependency. Targeting for the FES-I and the short FES-I was somewhat suboptimal as the participants on average reported less FoF than expected. A negligible gender DIF was found for two items in the FES-I and for one item in the short FES-I. Reliability was high (PSI >0.86), and the response category thresholds worked as intended for both the FES-I and the short FES-I. The FES-I and the short FES-I have sufficient measurement properties in persons with LEoP. Both versions can be used to assess fear of falling (or FoF) in this population.

Validation of the English version of the arrhythmia-specific questionnaire in tachycardia and arrhythmia (ASTA): a Rasch evaluation study

BackgroundPatient-reported outcome measures are important in person-centered care, providing valuable information about patients’ experiences. Disease-specific questionnaires add important information about a certain disease in comparison to generic questionnaires. Questionnaires need to be validated in the targeted population to achieve reliable data. The purpose with the study was to use Rasch measurement theory to evaluate the English version of the ASTA questionnaire.MethodsThe Rasch model theory was used to evaluate global and item fit, targeting, response category functioning, local independency, unidimensionality, differential item functioning (DIF) for gender and age, and reliability.ResultsThe study included 202 patients undergoing DC conversion or catheter ablation at the Centre for Heart Rhythm Disorders at the University of Adelaide, Australia. The mean age was 67 years and 30% were women. Most patients had atrial fibrillation (n = 179), others had atrial flutter or had a combination. One of nine items demonstrated unsatisfactory model fit in the ASTA Symptom scale and two of 13 in the ASTA Health-Related Quality of Life (HRQoL) scale. Unidimensionality was supported for both scales. The targeting was acceptable except for the lower end of the scales. Both scales showed reversed thresholds for the response categories “quite a lot” and “a lot” (eight of ASTA symptoms and 12 of ASTA HRQoL items). Some problems with local dependency were detected in both scales. The reliability (person separation index) was satisfactory: 0.75 for the ASTA symptom scale and 0.77 for the ASTA HRQoL scale. No DIF for gender and age were detected.ConclusionsThe English version of the ASTA questionnaire demonstrated satisfactory measurement properties according to the Rasch model. However, it needs to be evaluated in patients with other arrhythmias. The response categories should be considered as well as DIF in further validation. The ASTA questionnaire can be used for assessments of symptoms and HRQoL between groups of different ages and genders in patients with arrhythmia.

The modified COVID-19 Yorkshire Rehabilitation Scale (C19-YRSm) patient-reported outcome measure for Long Covid or Post-COVID-19 syndrome.

BackgroundThe C19‐YRS is the literature's first condition‐specific, validated scale for patient assessment and monitoring in Post‐COVID‐19 syndrome (PCS). The 22‐item scale's subscales (scores) are symptom severity (0–100), functional disability (0–50), additional symptoms (0–60), and overall health (0–10).ObjectivesThis study aimed to test the scale's psychometric properties using Rasch analysis and modify the scale based on analysis findings, emerging information on essential PCS symptoms, and feedback from a working group of patients and professionals.MethodsData from 370 PCS patients were assessed using a Rasch Measurement Theory framework to test model fit, local dependency, response category functioning, differential item functioning, targeting, reliability, and unidimensionality. The working group undertook iterative changes to the scale based on the psychometric results and including essential symptoms.ResultsSymptom severity and functional disability subscales showed good targeting and reliability. Post hoc rescoring suggested that a 4‐point response category structure would be more appropriate than an 11‐point response for both subscales. Symptoms with binary responses were placed in the other symptoms subscale. The overall health single‐item subscale remained unchanged.ConclusionA 17‐item C19‐YRSm was developed with subscales (scores): symptom severity (0–30), functional disability (0–15), other symptoms (0–25), and overall health (0–10).

The Reliability and Validity of the Korean Version of Hospital Anxiety and Depression Scale Using Rasch Measurement Theory in Patients with Parkinson’s Disease

Background: Depression and anxiety are prevalent and can cause suffering in patients with Parkinson’s disease (PD). The Korean version of the Hospital Anxiety and Depression Scale (K-HADS) has been widely used to assess depression and anxiety symptoms in Korean patient with PD. The present study aimed to assess the reliability and validity of the K-HADS using Rasch measurement analysis.Methods: A total of 106 PD patients (54 males, 52 females) who met the diagnostic criteria of the United Kingdom Brain Bank were recruited. Unidimensionality, the Rasch model fit, response category functioning, patient-item distribution, and the separation reliability of the K-HADS depression (K-HADS-D) and anxiety (K-HADS-A) subscales were statistically evaluated.Results: The mean K-HADS-D and K-HADS-A scores were 8.08±4.69 (mean±standard deviation) and 5.44±4.18, respectively. Cronbach’s α coefficients of the K-HADS-D and K-HADS-A were 0.82 and 0.83. The Rasch analysis revealed that the K-HADS-D and K-HADS-A showed unidimensionality and no disordered functioning was observed in the 4-point polytomous scale. However, both K-HADS-D and K-HADS-A exhibited suboptimal separation reliability, while the K-HADS-A showed inadequate scale targeting with floor effect.Conclusions: The present study comprises the first validation of the K-HADS using the Rasch measurement model, suggesting that the K-HADS-D and K-HADS-A are clinimetrically acceptable and reliable scales for use in Korean patients with PD. However, the moderate person separation indices implicate the relatively low discriminatory ability of the K-HADS in our study patients.

Investigating psychometric properties of the arm activity measure \u2013 Thai version (ArmA-TH) sub\u2010scales using the Rasch model

BackgroundThis study investigated the ArmA-TH sub-scale measurement properties based on item response theory using the Rasch model.MethodsPatients with upper limb hemiplegia resulting from cerebrovascular and other brain disorders were asked to complete the ArmA-TH questionnaire. Rasch analysis was performed to test how well the ArmA-TH passive and active function sub-scales fit the Rasch model by investigating unidimensionality, response category functioning, reliability of person and item, and differential item functioning (DIF) for age, sex, and education.ResultsParticipants had stroke or other acquired brain injury (n = 185), and the majority were men (126, 68.1 %), with a mean age of 55 (SD 22). Most patients (91, 49.2 %) had graduated from elementary/primary school. For the ArmA-TH passive function scale, all items had acceptable fit statistics. The scale’s unidimensionality and local independence were supported. The reliability was acceptable. A disordered threshold was found for five items, and none indicated DIF. For the ArmA-TH active function scale, one item was misfit and three were locally dependent. The reliability was good. No items showed DIF. All items had disordered thresholds, and the data fitted the Rasch model better after rescoring.ConclusionsBoth sub-scales of ArmA-TH fitted the Rasch model and were valid and reliable. The disordered thresholds should be further investigated.

Item banks for measurement of refractive error-specific quality of life.

To evaluate the psychometric properties of refractive error-specific quality of life (QoL) item banks and assess their performance using computerised adaptive testing (CAT) simulations. In this cross-sectional study a 392-item questionnaire, grouped under 11 QoL domains, was interviewer-administered to 305 people with refractive error [mean age±S.D., 30.5±14.1 (range (18 to 83) years; male, 50.5%; mean±S.D. spherical equivalent refractive error -2.4±2.9 (range: -15.0 to +11.0) Dioptres; spectacles (n=257), contact lens (n=37), refractive surgery (n=25), uncorrected refractive error (n=57)]. Rasch analysis was conducted on each QoL domain using the Andrich rating scale model to investigate parameters including response category functioning, person- and item-reliability, infit and outfit statistics, unidimensionality, targeting, differential item functioning and local item dependency. The resulting item banks underwent CAT simulations in 1,000 cases with 'high' and 'moderate' precision stopping rules. Rasch analysis iterations resulted in 13 refractive error-specific item banks (Convenience, Health concerns, Economic, Activity limitation, Mobility, Emotional, Social, Visual symptoms frequency, Visual symptoms severity, Visual symptoms bothersome, Comfort symptoms frequency, Comfort symptoms severity and Comfort symptoms bothersome), containing a total of 366 items. The item banks had good psychometric properties including satisfactory measurement precision, infit and outfit statistics and unidimensionality. In CAT simulations, the mean number of items required to achieve high and moderate measurement precision was 9.4 and 4.7, respectively. Overall, refractive error-specific QoL item banks show promise in their ability to comprehensively and precisely evaluate a range of quality of life parameters. These items banks when administered using a CAT system offer unique outcome tools for implementation in clinical trials, healthcare and research.

Development of the Vision Impairment in Low Luminance Questionnaire.

PurposeThe purpose of this study was to design and evaluate an instrument for assessing vision-related quality of life appropriate for the specific visual impairment characteristic for all stages of age-related macular degeneration (AMD), with a focus on the low luminance deficit in early/intermediate stages.MethodsA standardized questionnaire was developed in three steps with participants with early, intermediate, and late AMD: (1) based on in-depth interviews (n = 19) and two focus group discussions (n = 5 each), content was developed followed by 2. (2) The questionnaire development using cognitive debriefing interviews (n = 3) and leading to a preliminary version of the questionnaire. (3) This version was then administered to 127 participants with early, intermediate, and late AMD. Psychometric properties, such as response category functioning (floor and ceiling effects) and targeting of item difficulty to patient ability of the pilot Vision Impairment in Low Luminance (VILL) questionnaire were evaluated using Rasch analysis.ResultsThe preliminary VILL questionnaire consisted of 68 items with a 5-step response scale. Several items were removed based on floor/ceiling effects or misfit and a final pool of 37 items remained. The response scale was collapsed to four categories as one category was underutilized. The targeting of the instrument was good with minimal difference in person and item means (0.52 logits). Precision was also good with a person separation index of 3.55 and reliability of 0.93. There was evidence of multidimensionality (eigenvalue of the first contrast = 5.95) in the scale, which could be resolved by splitting the items into subscales including a reading, mobility, and emotional well-being subscale.ConclusionsIndividuals with AMD report difficulties with vision-related activities and functioning under visually challenging conditions at all stages of the disease. These aspects were considered when developing the 37-item VILL, which demonstrates promising psychometric characteristics. Further assessments of reliability and validity are warranted.Translational RelevanceThe VILL questionnaire is a new patient-reported outcome (PRO) measure developed for future use in AMD studies.

The impact of vision impairment on vision-related quality of life of patients with neovascular age-related macular degeneration.

To investigate the validity and reliability of the Greek Impact of Vision Impairment Questionnaire (IVI) and to explore the predictors of vision-related quality of life (VRQoL) in individuals with neovascular age-related macular degeneration (nAMD). About 191 patients completed the IVI and the SF-12 Health Survey, and were assessed on visual exams. A random group of 20 participants completed the IVI twice with a 2 weeks interval, to assess test-retest reliability. About 102 patients completed the IVI 1 year later in a follow-up examination. Rasch analysis was used to evaluate response category functioning, scale precision, unidimensionality, scale targeting and differential item functioning. Stepwise multiple linear regression analyses identified predictors of VRQoL. Test-retest reliability of IVI items was calculated from 0.86 to 0.98. The six response categories were merged into four to figure out disordered thresholds. Rasch analysis concluded in three scales: Mobility and Independence, Reading and Accessing Information, and Emotional Wellbeing. Regarding convergent validity, the IVI scores had significant associations with SF-12 components (ρ = 0.28-0.47) and measurements of visual acuity (ρ = 0.39-0.66). Worse VRQoL at 1 year follow-up was correlated with decline in distance and near VA. Distance VA and the SF-12 components were common predictors for all three subscales. The duration of disease was a significant predictor for the emotional subscale. The Greek IVI was found to assess AMD patients' perceptions of VRQoL in a valid, reliable and responsive to eyesight manner. VRQoL was mainly established by patients' distance VA and mental health.

Psychometric Properties of the Walking Impact Scale (Walk-12) in Persons with Late Effects of Polio.

Many persons with late effects of polio (LEoP) perceive walking limitations in everyday life. A common rating scale to assess walking limitations is the Walking Impact Scale (Walk-12). However, there is limited knowledge about its psychometric properties. To investigate the psychometric properties of Walk-12 in persons with LEoP. Rasch model analysis of cross-sectional data. University hospital. A total of 325 persons with LEoP (175 women; mean age 70 ± 10 years). The Walk-12, comprising 12 items with five response categories ranging from 1 (not at all) to 5 (extremely). Data of Walk-12 were collected by a postal survey. The Rasch model analysis was used to analyze unidimensionality of the scale, local dependency, targeting, hierarchical order of items, Differential Item Functioning (DIF), response category functioning, and reliability (Person Separation Index, PSI). Raw score transformation to interval measurements was also performed. The analysis revealed that Walk-12 was multidimensional and suffered from some local dependency. Targeting was compromised among persons with less and more walking limitations. Hierarchically, the most difficult item to perform was "running" and the easiest was "walking indoors with support". There was a minor DIF for gender in one item ("support when walking outdoors"). Reliability was high (PSI = 0.94). Disordered response category thresholds were found for three items; when merging the middle response categories for these items model fit slightly improved and unidimensionality was achieved. The Walk-12, in its current version, does not fully meet the rigorous psychometric Rasch measurement standards in persons with LEoP. Further development of the scale is warranted, including merging response categories and complementing Walk-12 with objective measures of gait in order to improve targeting. As these limitations can be considered minor, the current version of Walk-12 can still be useful for research and clinical practice.

The Monotonic Polynomial Graded Response Model: Implementation and a Comparative Study.

We present a monotonic polynomial graded response (GRMP) model that subsumes the unidimensional graded response model for ordered categorical responses and results in flexible category response functions. We suggest improvements in the parameterization of the polynomial underlying similar models, expand upon an underlying response variable derivation of the model, and in lieu of an overall discrimination parameter we propose an index to aid in interpreting the strength of relationship between the latent variable and underlying item responses. In applications, the GRMP is compared to two approaches: (a) a previously developed monotonic polynomial generalized partial credit (GPCMP) model; and (b) logistic and probit variants of the heteroscedastic graded response (HGR) model that we estimate using maximum marginal likelihood with the expectation-maximization algorithm. Results suggest that the GRMP can fit real data better than the GPCMP and the probit variant of the HGR, but is slightly outperformed by the logistic HGR. Two simulation studies compared the ability of the GRMP and logistic HGR to recover category response functions. While the GRMP showed some ability to recover HGR response functions and those based on kernel smoothing, the HGR was more specific in the types of response functions it could recover. In general, the GRMP and HGR make different assumptions regarding the underlying response variables, and can result in different category response function shapes.

Constructs Evaluation of Student Attitudes towards Science

Students' attitudes towards science (SAS) is a prominent research area as evident in the science education literature. Many SAS studies incorporated science confidence (SC), science enjoyment (SE) and importance of science (IS) into the study of SAS. However, the incorporation of these constructs often depends on the subjective judgment of the researchers. This study examines the incorporation of the three constructs in the measure of SAS based on the Asian Student Attitudes Towards Science Class (ASATSC) instrument. A total of 1,133 7th to 11th graders from China completed a survey of the three constructs. Data was collectively assessed in terms of fit to the Rasch model that requires invariant and consistent response category functioning. Results indicated that SC was not correlated well with IS whilst SC and SE were consistent with each other in the measure of SAS. Recommendations were provided on how constructs on the measurement of SAS can be better designed.

Measuring Anxiety in Patients With Early-Stage Parkinson's Disease: Rasch Analysis of the State-Trait Anxiety Inventory.

The State-Trait Anxiety Inventory (STAI), composed of two 20-item subscales (STAI-state and STAI-trait), has been increasingly used to assess anxiety symptoms in patients with Parkinson's disease (PD). However, the clinimetric attributes of the STAI under the statistical framework of the item-response theory (IRT) have not been fully elucidated within this population to date. We performed an IRT-based Rasch analysis of the STAI outcomes of patients with de novo PD from the Parkinson's Progression Markers Initiative database. The unidimensionality, Rasch model fit, scale targeting, separation reliability, differential item functioning, and response category utility of the STAI were statistically evaluated. A total of 326 (209 males, 117 females) patients without cognitive dysfunction were enrolled in our study. The original versions of the STAI-state and STAI-trait had acceptable separation reliability but lacked appropriate response category functioning, exhibited scale off-targeting, and several items demonstrated poor fit to the Rasch model. The response categories were reduced from four to three, and the rescored three-point TASI-trait demonstrated a marked improvement in clinimetric properties without a significant impact on unidimensionality and separation reliability. The rescored three-point version of the STAI-state required the additional removal of four misfitting items in order to improve the Rasch model fit. To our knowledge, this is the first study to assess the measurement properties based on the IRT of the STAI in patients with PD. Our Rasch analysis identified the components requiring possible amendments in order to improve the clinimetric attributes of the STAI.

Assessment of Psychometric Properties of an Oral Health Care Measure of Cultural Competence Among Dental Students Using Rasch Partial Credit Model.

Reliability, validity, and feasibility of the only validated oral health care measure of cultural competence, the Knowledge, Efficacy, and Practices Instrument (KEPI), have been confirmed. However, the instrument's psychometric properties including item and person reliability, category response functioning, and scale targeting, as well as differential scale functioning for subgroups, have not yet been examined. The aim of this study was to test the psychometric properties of KEPI among dental students using Rasch Partial Credit Model to determine if this model provided broader valid information that cannot be demonstrated according to Classical Test Theory. A total 1,290 dental students in the first or final semester at four U.S. dental schools were invited to participate in the study in 2016. Of those, 1,231 individuals completed the survey, for a 95.4% response rate. The participants were 613 males and 618 females and 889 non-underrepresented minority (URM) and 342 URM students. The Rasch Partial Credit Model assessed the psychometric properties of KEPI's 20 items/three subscales. Differential scale functioning was found in the Culture-Centered Practice and Efficacy of Assessment subscales. Four items were endorsed differentially by gender; four items were endorsed differentially by URM/non-URM students. This study examined the psychometric properties of the KEPI using Rasch analysis to assess differential item functioning by dental student gender and race. The results provided valid evidence for the high internal reliability, measurement properties, and unidimensionality for the KEPI domains, ideal targeting, and well response category functioning, showing that the KEPI is a reliable instrument for measuring the subscales Knowledge of Diversity, Culture-Centered Practice skills, and Efficacy of Assessment for health care providers.

Construct Validity of the Spanish Versions of the Memorial Symptom Assessment Scale Short Form and Condensed Form: Rasch Analysis of Responses in Oncology Outpatients

ContextThe Memorial Symptom Assessment Scale (MSAS) is a self-rating instrument for the assessment of symptom distress in cancer patients. The Spanish version of the MSAS has recently been validated. However, we lack evidence of the internal construct validity of the shorter versions (short form [MSAS-SF] and condensed form [CMSAS]). In addition, rigorous testing of these scales with modern psychometric methods is needed. ObjectivesThe aim of this study was to evaluate the internal construct validity and reliability of the Spanish versions of the MSAS-SF and CMSAS in oncology outpatients using Rasch analysis. MethodsData from a convenience sample of oncology outpatients receiving chemotherapy (n = 306; mean age 60 years; 63% women) at a university hospital were analyzed. The Rasch unidimensional measurement model was used to examine response category functioning, item hierarchy, targeting, unidimensionality, reliability, and differential item functioning by age, gender, and marital status. ResultsThe response category structure of the symptom distress items was improved by collapsing two categories. The scales were adequately targeted to the study patients, showed overall Rasch model fit (mean Infit MnSq ranged from 0.98 to 1.05), met criteria for unidimensionality, and the reliability of scores was good (person reliability > 0.80), except for the CMSAS prevalence scale. Only four items showed differential item functioning. ConclusionThe present study demonstrated that the Spanish versions of the MSAS-SF and CMSAS have adequate psychometric properties to evaluate symptom distress in oncology outpatients. Additional studies of the CMSAS are recommended.

Validity of the school setting interview for students with special educational needs in regular high school \u2013 a Rasch analysis

BackgroundParticipation in education is a vital component of adolescents’ everyday life and a determinant of health and future opportunities in adult life. The School Setting Interview (SSI) is an instrument which assesses student-environment fit and reflects the potential needs for adjustments to enhance students’ participation in school activities. The aim of the study was to investigate the psychometric properties of the SSI for students with special educational needs in regular high school.MethodsA sample of 509 students with special educational needs was assessed with the SSI. The polytomous unrestricted Rasch model was used to analyze the psychometric properties of the SSI regarding targeting, model fit, differential item functioning (DIF), response category functioning and unidimensionality.ResultsThe SSI generally confirmed fit to assumptions of the Rasch model. Reliability was acceptable (0.73) and the SSI scale was able to separate students into three different levels of student-environment fit. DIF among gender was detected in item “Remember things” and in item “Homework” DIF was detected among students with or without diagnosis. All items had disordered thresholds. The SSI demonstrated unidimensionality and no response dependence was present among items.ConclusionThe results suggest that the SSI is valid for use among students with special educational needs in order to provide and evaluate environmental adjustments. However, the items with the detected DIF and the SSI rating scale with its disordered thresholds needs to be further scrutinized.

Reliability, validity and responsiveness of the Greek MacDQoL individualized measure of the impact of macular degeneration on quality of life.

To assess the psychometric properties of the Greek Macular Disease-Dependent Quality of Life Questionnaire (MacDQoL). The MacDQoL was translated in Greek and administered to 191 patients with neovascular age-related macular degeneration (AMD). To assess validity, all patients completed the Greek SF-12 health survey and underwent vision measurements. For test-retest reliability, a subset of twenty participants completed the MacDQoL twice, 2weeks apart. Responsiveness was assessed on 102 patients who completed the MacDQoL at a follow-up visit, 1year later. Rasch analysis was used to assess the Greek MacDQoL's response category functioning, precision, unidimensionality, targeting and differential item functioning. Internal and test-retest reliability of the average weighted impact (AWI) was 0.952 and 0.97, respectively. Test-retest reliability of MacDQoL items ranged from 0.78 to 0.99. Principal component analysis revealed three subscales (activities, embarrassment and family life), which were also confirmed by confirmatory factor analysis. Rasch analysis revealed poor functionality of response categories and that was resolved by collapsing response categories and using the impairment scores only. In terms of convergent validity, the AWI and revised MacDQoL scales showed significant correlations with SF-12 summary scales (ρ=0.21-0.30) and vision assessments (ρ=0.31-0.46). Poorer AMD-related QoL at 1-year follow-up was associated with deterioration in distance visual acuity and worse eye near visual acuity. The Greek MacDQoL is a reliable, valid and sensitive to change in vision instrument for assessing AMD patients' perceptions of QoL. However, Rasch analysis revealed that its multiplicative rating scale is flawed. Scientific measurement was restored with a number of revisions to the questionnaire.