The Social Insurance Literacy Questionnaire (SILQ): Development and Psychometric Evaluation.

PURPOSE: For clients to understand social insurance decisions and processes, information from authorities needs to be comprehensible, and clients need sufficient individual abilities. These dimensions are captured by the concept social insurance literacy, which has been operationalized into a measure, the Social Insurance Literacy Questionnaire (SILQ). The aim of this study was to describe the development of the SILQ and evaluate its psychometric properties using Rasch measurement theory. METHODS: The development of the SILQ included a Delphi study and cognitive interviews. A preliminary version, divided on four scales corresponding to the domains of the concept (obtaining information, understanding information, acting on information, and system comprehensibility) was psychometrically evaluated according to Rasch measurement theory, in a survey to a stratified random sample of people on sick leave (n = 1151) sent out in the fall of 2020. RESULTS: Overall, the items in the final version of the SILQ demonstrated good fit to the Rasch model, and the response scale worked as intended. Unidimensionality was supported for all scales, but minor problems with local dependency was detected for three items. The person separation was 0.80 for the Obtain scale, 0.82 for the Understand scale, 0.68 for the Act scale, and 0.81 for the System scale. Corresponding ordinal alpha values were 0.91, 0.91, 0.86, and 0.91, respectively. CONCLUSION: This study is a first step toward exploring literacy in the social insurance field. The SILQ covers individual abilities and systems' comprehensibility, and the results show that it has acceptable psychometric properties.

Evaluating the impact of calibration of patient-reported outcomes measures on results from randomized clinical trials: a simulation study based on Rasch measurement theory.

BACKGROUND: Meaningfully interpreting patient-reported outcomes (PRO) results from randomized clinical trials requires that the PRO scores obtained in the trial have the same meaning across patients and previous applications of the PRO instrument. Calibration of PRO instruments warrants this property. In the Rasch measurement theory (RMT) framework, calibration is performed by fixing the item parameter estimates when measuring the targeted concept for each individual of the trial. The item parameter estimates used for this purpose are typically obtained from a previous "calibration" study. But imposing this constraint on item parameters, instead of freely estimating them directly in the specific sample of the trial, may hamper the ability to detect a treatment effect. The objective of this simulation study was to explore the potential negative impact of calibration of PRO instruments that were developed using RMT on the comparison of results between treatment groups, using different analysis methods. METHODS: PRO results were simulated following a polytomous Rasch model, for a calibration and a trial sample. Scenarios included varying sample sizes, with instrument of varying number of items and modalities, and varying item parameters distributions. Different treatment effect sizes and distributions of the two patient samples were also explored. Cross-sectional comparison of treatment groups was performed using different methods based on a random effect Rasch model. Calibrated and non-calibrated approaches were compared based on type-I error, power, bias, and variance of the estimates for the difference between groups. RESULTS: There was no impact of the calibration approach on type-I error, power, bias, and dispersion of the estimates. Among other findings, mistargeting between the PRO instrument and patients from the trial sample (regarding the level of measured concept) resulted in a lower power and higher position bias than appropriate targeting. CONCLUSIONS: Calibration does not compromise the ability to accurately assess a treatment effect using a PRO instrument developed within the RMT paradigm in randomized clinical trials. Thus, given its essential role in producing interpretable results, calibration should always be performed when using a PRO instrument developed using RMT as an endpoint in a randomized clinical trial.

Rasch Analysis of Patient- and Parent-Reported Outcome Measures in the International Consortium for Health Outcomes Measurement Standard Set for Cleft Lip and Palate.

OBJECTIVES: The aim of this study was to evaluate the psychometric performance of the patient- and parent-reported measures in the International Consortium for Health Outcomes Measurement (ICHOM) Standard Set for Cleft Care, and to identify ways of improving concept coverage. METHODS: Data from 714 patients with cleft lip and/or palate, aged 8 to 9, 10 to 12.5, and 22 years were collected between November 2015 and April 2019 at Erasmus University Medical Center, Boston Children's Hospital, Duke Children's Hospital, and from participating sites in the CLEFT-Q Phase 3 study. The Standard Set includes 9 CLEFT-Q scales, the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire, the Child Oral Health Impact Profile-Oral Symptoms Scale (COHIP-OSS), and the Intelligibility in Context Scale (ICS). Targeting, item-fit statistics, thresholds for item responses, and measurement precision (PSI) were analyzed using Rasch measurement theory. RESULTS: The proportion of the sample to score within each instruments range of measurement varied from 69% (ICS) to 92% (CLEFT-Q teeth and COHIP-OSS). Specific problems with individual items within the NOSE and COHIP-OSS questionnaires were noted, such as poor item fit to the Rasch model and disordered thresholds (6 of 10). Reliability measured with PSI was above 0.82 for the ICS and all but one CLEFT-Q scale (speech distress). PSIs were lowest for the COHIP-OSS (0.43) and NOSE questionnaire (0.35). CONCLUSION: The patient- and parent-reported components within the facial appearance, psychosocial function, and speech domains are valid measures; however, the facial function and oral health domains are not sufficiently covered by the CLEFT-Q eating and drinking, NOSE, and COHIP-OSS, and these questionnaires may not be accurate enough to stratify cleft-related outcomes.

Using the Rasch measurement theory to assess the psychometric properties of the Hopkins Symptom Checklist-10 in adolescents.

BACKGROUND: The Hopkins Symptom Checklist-10 (HSCL-10) is widely used to measure psychological distress in adolescents. To provide valid and reliable results and generate recommendations for practice and policies, instruments with sound psychometric properties are required. The purpose of this study is to use Rasch measurement theory to assess the psychometric properties of the HSCL-10 among adolescents aged 13-19. METHODS: In this cross-sectional study, 6445 adolescents responded to a web-based questionnaire. Data were collected from lower and upper secondary schools in Norway during 2018. The data were analysed using the partial credit parameterisation of the unidimensional Rasch model. RESULTS: HSCL-10 was found to be unidimensional and to have acceptable reliability. One pair of items showed response dependency. The targeting of the instrument could have been better. All items had ordered thresholds. Three items under-discriminated and three displayed differential item functioning regarding gender. CONCLUSIONS: HSCL-10 has potential for measuring psychological distress in adolescents, though there is room for improvement. To further improve this instrument, some items should be rephrased.

The Ms. Olsen test: Measurement properties of a short test of nursing staffs' competence in clinical decision-making.

AIMS: To assess the measurement properties of the Ms. Olsen test for registered nurses and assistant nurses, respectively, and suggest cut-off points between competence levels. DESIGN: Cross-sectional study. The results were analysed by implementing the Rasch Measurement Theory. METHODS: Nursing staff working in various health care settings participated (n = 757). To measure the competence of nursing staff in clinical decision-making, a 19-item scale from the Nursing Older People-Competence Evaluation Tool-the 'Ms. Olsen test'-was used. Data were collected in October 2017, 2018 and 2019. RESULTS: The Ms. Olsen test showed reasonably good measurement properties for registered nurses and assistant nurses respectively. Results show slightly better measurement properties for registered nurses than for assistant nurses. The cut-off for registered nurses, 0.62, corresponds to managing approximately two-thirds of the items while, for assistant nurses, the cut-off of 0.01 corresponds to managing approximately half of the items. CONCLUSION: The Ms. Olsen test is a short (7- to 10-min) test measuring competence in clinical decision-making among nursing staff working in older people nursing. Despite reasonably good measurement properties, this should be considered an initial validation in the development of a short test for assessing clinical decision-making among nursing staff in various health care setting. IMPACT: Several scales aiming to measure nursing competence have been developed over the last decade, but measurement properties (beyond classical test theory) are seldom evaluated, few scales concern other staff groups than registered nurses and few scales have proposed or established cut-offs for safe practice. The Ms. Olsen test is a short test of clinical decision-making that demonstrates reasonably good measurement properties. Cut-off points for registered nurses and assistant nurses were established. The Ms. Olsen test may be used to measure and evaluate competence in clinical decision-making among nursing staff working in older people nursing and educational settings.

Using Rasch measurement theory to assess the psychometric properties of a depressive symptoms scale in Norwegian adolescents.

BACKGROUND: Scales measuring depressive symptoms in adolescents and adults are widely used for epidemiological purposes. The purpose of this study is to use Rasch measurement theory to examine the psychometric properties of a six-item scale intended to measure depressive symptoms in Norwegian adolescents. METHODS: The study is based on cross-sectional data from Ungdata, a survey conducted by the Norwegian Social Research Institute in cooperation with Regional Centres for Drug Rehabilitation in 2017. The target group comprised 13- to 19-years olds in Norway. Six items with four response categories, intended to measure depressive symptoms, were analysed. The analysis focused on invariance, including differential item functioning across gender and school levels. In addition, targeting, possible multidimensionality, response dependency, and the categorisation of the items were analysed. RESULTS: The scale measuring depressive symptoms shows good reliability and, on the whole, the items work well. However, one item, 'had sleep problems', clearly misfit and another, 'worried too much about things', works differently for males and females. CONCLUSIONS: The scale has the potential to measure depressive symptoms in adolescents though there is room for improvement. To further improve the scale, the item concerning sleep problems should be rephrased.

Development and validation of the McGill body image concerns scale for use in head and neck oncology (MBIS-HNC): A mixed-methods approach.

OBJECTIVE: The aim of this study was to develop and validate a patient-reported outcome measure to evaluate body image concerns in head and neck cancer (HNC) patients. METHODS: Items were created using a combination of deductive (eg, US Food and Drug Administration Qualification of Clinical Outcome Assessments, literature review) and inductive approaches (eg, subject matter experts, HNC patients). Items were translated for use in both Canadian English and Canadian French using back-translation. A two-step empirical validation process using the Classical Test Theory (CTT) and Rasch Measurement Theory (RMT) was conducted with 224 and 258 HNC patients, respectively, having undergone disfiguring surgery within the past 3 years. RESULTS: Analyses suggest two subscales for MBIS-HNC: social discomfort (10 items) and negative self-image (11 items). The McGill Body Image Concerns Scale-Head and Neck Cancer (MBIS-HNC) is reliable with high internal consistency (0.98), high test-retest reliability over a two-week period (ICC = 0.88), moderate to high convergent validity (range r = 0.43-0.81), and divergent validity (range r = 0.12-0.15). RMT was used in addition to CTT. Disordered thresholds led to the modification of the number of response options, and items were deleted based on differential item functioning and high local dependency. Unidimensionality of both subscales and supporting a total score was confirmed. The measure was however characterized by the presence of an important floor effect, confirmed with poor targeting as demonstrated by the person-item threshold distribution. CONCLUSION: Evidence gathered from our theory-driven validation study using CTT and RMT provides practitioners and researchers with a useful and easy to use self-report measure.

DEMQOL and DEMQOL-Proxy: a Rasch analysis among those diagnosed with dementia.

BACKGROUND: In previous work we concluded that DEMQOL and DEMQOL-Proxy can provide robust measurement of HRQL in dementia when scores are derived from analysis using the Rasch model. As the study sample included people with mild cognitive impairment, we undertook a replication study in the subsample with a diagnosis of dementia (PWD). PWD constitute the population for whom DEMQOL and DEMQOL-Proxy were originally developed. METHODS: We conducted a Rasch model analysis using the RUMM2030 software to re-evaluate DEMQOL (441 PWD) and DEMQOL-Proxy (342 family carers). We evaluated scale to sample targeting, ordering of item thresholds, item fit to the model, and differential item functioning (sex, age, severity, relationship), local independence, unidimensionality and reliability. RESULTS: For both DEMQOL and DEMQOL-Proxy, results were highly similar to the results in the original sample. We found the same problems with content and response options. CONCLUSIONS: DEMQOL and DEMQOL-Proxy can provide robust measurement of HRQL in people with a diagnosis of dementia when scores are derived from analysis using the Rasch model. As in the wider sample, the problems identified with content and response options require qualitative investigation in order to improve the scoring of DEMQOL and DEMQOL-Proxy.

Cross-country comparisons of trends in adolescent psychosomatic symptoms - a Rasch analysis of HBSC data from four Nordic countries.

BACKGROUND: To analyse the psychometric properties of the HBSC Symptom Checklist (HBSC-SCL) on psychosomatic symptoms with a focus on the operating characteristics of the items, and on the impacts of measurement distortions on the comparisons of person measures across time and between countries. METHODS: Data were collected in 1993/94, 1997/98, 2001/02, 2005/06, 2008/09, 2013/14 in Denmark, Finland, Norway and Sweden as part of the Health Behaviour in School-aged Children (HBSC) study. Data comprised 116,531 students 11, 13 and 15 years old. Rasch analysis was conducted of the HBSC-SCL consisting of eight items with a focus on Differential Item Functioning (DIF) and item threshold ordering. The impacts of DIF and threshold disordering on trend analyses were analysed in a subsample consisting of 15 years old students. RESULTS: One item shows evidence of severe DIF and the categorisation of some items does not seem to work as intended. Analyses of changes based on proportions of psychosomatic symptoms show that bad item functioning affects some comparisons between countries across time: A four percentage point difference between 15 years old girls in Finland and Sweden concerning the rate of increase of psychosomatic symptoms from 1994 to 2014 disappears when the problems with DIF and disordered item thresholds are taken into account. Although the proportions of students with psychosomatic symptoms are clearly higher 2014 than 1994 in all four countries the shape of most trends is nonlinear. CONCLUSIONS: Some of the cross-country comparisons were distorted because of DIF and problems related to disordering of the item thresholds. The comparisons among girls between Finland and Sweden were affected by the problems pertaining to the original measure of psychosomatic symptoms, while the trend patterns among boys were not much affected. In addition to confirming increasing rates of adolescent mental health problems in the Nordic countries, the substantive analyses in the current study show that Finland is joining Sweden in having the sharpest increase among older adolescents, in particular among girls. To improve the functioning of the scale the DIF item could be removed or replaced and response categories collapsed in post hoc analyses.

DEMQOL and DEMQOL-Proxy: a Rasch analysis.

BACKGROUND: DEMQOL and DEMQOL-Proxy are widely used patient reported outcome measures (PROMs) of health related quality of life in people with dementia (PWD). Growing interest in routine use of PROMs in health care calls for more robust instruments that are potentially fit for reliable and valid comparisons at the micro-level (patients) and meso-level (clinics, hospitals, care homes). METHODS: We used modern psychometric methods (based on the Rasch model) to re-evaluate DEMQOL (1428 PWDs) and DEMQOL-Proxy (1022 carers) to ensure they are fit for purpose. We evaluated scale to sample targeting, ordering of item thresholds, item fit to the model, and differential item functioning (sex, age, relationship), local independence, unidimensionality and reliability on the full set of items and a smaller item set. RESULTS: For both DEMQOL and DEMQOL-Proxy the smaller item set performed better than the original item set. We developed revised scores using the items from the smaller set. CONCLUSIONS: We have improved the scoring of DEMQOL and DEMQOL-Proxy using the Rasch measurement model. Future work should focus on the problems identified with content and response options.

Development of a new Rasch-based scoring algorithm for the National Eye Institute Visual Functioning Questionnaire to improve its interpretability.

BACKGROUND: The NEI VFQ-25 has undergone psychometric evaluation in patients with varying ocular conditions and the general population. However, important limitations which may affect the interpretation of clinical trial results have been previously identified, such as concerns with reliability and validity. The purpose of this study was to evaluate the National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) and make recommendations for a revised scoring structure, with a view to improving its psychometric performance and interpretability. METHODS: Rasch Measurement Theory analyses were conducted in two stages using pooled baseline NEI VFQ-25 data for 2487 participants with retinal diseases enrolled in six clinical trials. In stage 1, we examined: scale-to-sample targeting; thresholds for item response options; item fit statistics; stability; local dependence; and reliability. In stage 2, a post-hoc revision of the scoring structure (VFQ-28R) was created and psychometrically re-evaluated. RESULTS: In stage 1, we found that the NEI VFQ-25 was mis-targeted to the sample, and had disordered response thresholds (15/25 items) and mis-fitting items (8/25 items). However, items appeared to be stable (differential item functioning for three items), have minimal item dependency (one pair of items) and good reliability (person-separation index, 0.93). In stage 2, the modified Rasch-scored NEI VFQ-28-R was assessed. It comprised two broad domains: Activity Limitation (19 items) and Socio-Emotional Functioning (nine items). The NEI VFQ-28-R demonstrated improved performance with fewer disordered response thresholds (no items), less item misfit (three items) and improved population targeting (reduced ceiling effect) compared with the NEI VFQ-25. CONCLUSIONS: Compared with the original version, the proposed NEI VFQ-28-R, with Rasch-based scoring and a two-domain structure, appears to offer improved psychometric performance and interpretability of the vision-related quality of life scale for the population analysed.

Rasch analysis of the Italian Lower Extremity Functional Scale: insights on dimensionality and suggestions for an improved 15-item version.

OBJECTIVE: To investigate dimensionality and the measurement properties of the Italian Lower Extremity Functional Scale using both classical test theory and Rasch analysis methods, and to provide insights for an improved version of the questionnaire. DESIGN: Rasch analysis of individual patient data. SETTING: Rehabilitation centre. PARTICIPANTS: A total of 135 patients with musculoskeletal diseases of the lower limb. RESULTS: Patients were assessed with the Lower Extremity Functional Scale before and after the rehabilitation. Rasch analysis showed some problems related to rating scale category functioning, items fit, and items redundancy. After an iterative process, which resulted in the reduction of rating scale categories from 5 to 4, and in the deletion of 5 items, the psychometric properties of the Italian Lower Extremity Functional Scale improved. The retained 15 items with a 4-level response format fitted the Rasch model (internal construct validity), and demonstrated unidimensionality and good reliability indices (person-separation reliability 0.92; Cronbach's alpha 0.94). Then, the analysis showed differential item functioning for six of the retained items. The sensitivity to change of the Italian 15-item Lower Extremity Functional Scale was nearly equal to the one of the original version (effect size: 0.93 and 0.98; standardized response mean: 1.20 and 1.28, respectively for the 15-item and 20-item versions). CONCLUSION: The Italian Lower Extremity Functional Scale had unsatisfactory measurement properties. However, removing five items and simplifying the scoring from 5 to 4 levels resulted in a more valid measure with good reliability and sensitivity to change.

Clinical outcome measurement: Models, theory, psychometrics and practice.

In the last decade much has been made of the role that models play in the epistemology of measurement. Specifically, philosophers have been interested in the role of models in producing measurement outcomes. This discussion has proceeded largely within the context of the physical sciences, with notable exceptions considering measurement in economics. However, models also play a central role in the methods used to develop instruments that purport to quantify psychological phenomena. These methods fall under the umbrella term 'psychometrics'. In this paper, we focus on Clinical Outcome Assessments (COAs) and discuss two measurement theories and their associated models: Classical Test Theory (CTT) and Rasch Measurement Theory. We argue that models have an important role to play in coordinating theoretical terms with empirical content, but to do so they must serve: 1) as a representation of the measurement interaction; and 2) in conjunction with a theory of the attribute in which we are interested. We conclude that Rasch Measurement Theory is a more promising approach than CTT in these regards despite the latter's popularity with health outcomes researchers.

A review of empirical research related to the use of small quantitative samples in clinical outcome scale development.

INTRODUCTION: There has been a notable increase in the advocacy of using small-sample designs as an initial quantitative assessment of item and scale performance during the scale development process. This is particularly true in the development of clinical outcome assessments (COAs), where Rasch analysis has been advanced as an appropriate statistical tool for evaluating the developing COAs using a small sample. METHODS: We review the benefits such methods are purported to offer from both a practical and statistical standpoint and detail several problematic areas, including both practical and statistical theory concerns, with respect to the use of quantitative methods, including Rasch-consistent methods, with small samples. CONCLUSIONS: The feasibility of obtaining accurate information and the potential negative impacts of misusing large-sample statistical methods with small samples during COA development are discussed.

Lending a hand: can DASH items help ABILHAND improve manual ability measurement in multiple sclerosis?

BACKGROUND: Our examination in multiple sclerosis (MS) of the ABILHAND, a patient-reported outcome (PRO) instrument measuring manual ability, identified limited measurement range and precision. These deficiencies could lead to type II errors in clinical trials. OBJECTIVES: This paper aims to determine if ABILHAND's measurement performance in MS can be improved by adding relevant items from the Disabilities of the Arm, Shoulder and Hand scale (DASH). METHODS: The 23-item ABILHAND and 30-item DASH were administered to 461 people with MS. Data from the ABILHAND were combined with 16 DASH items to create a 39-item scale (AD-39). Using Rasch Measurement Theory methods, we compared the psychometric properties of AD-39 with ABILHAND. RESULTS: Data were analysed from 300 people. AD-39 performed robustly as a measure and had greater measurement range, lower floor and ceiling effects, and higher reliability (person separation index 0.97) than ABILHAND. Surprisingly, AD-39 appeared no better than ABILHAND at detecting group differences in self-reported hand function. CONCLUSION: Despite improving some psychometric properties, adding 16 DASH items to the ABILHAND did not improve its measurement performance to the degree expected. Our explanations for this anomaly emphasise the importance of evidence-based, conceptually driven scale modifications guided by hypothesis testing psychometric methods.

Using classical test theory, item response theory, and Rasch measurement theory to evaluate patient-reported outcome measures: a comparison of worked examples.

OBJECTIVE: To provide comparisons and a worked example of item- and scale-level evaluations based on three psychometric methods used in patient-reported outcome development-classical test theory (CTT), item response theory (IRT), and Rasch measurement theory (RMT)-in an analysis of the National Eye Institute Visual Functioning Questionnaire (VFQ-25). METHODS: Baseline VFQ-25 data from 240 participants with diabetic macular edema from a randomized, double-masked, multicenter clinical trial were used to evaluate the VFQ at the total score level. CTT, RMT, and IRT evaluations were conducted, and results were assessed in a head-to-head comparison. RESULTS: Results were similar across the three methods, with IRT and RMT providing more detailed diagnostic information on how to improve the scale. CTT led to the identification of two problematic items that threaten the validity of the overall scale score, sets of redundant items, and skewed response categories. IRT and RMT additionally identified poor fit for one item, many locally dependent items, poor targeting, and disordering of over half the response categories. CONCLUSIONS: Selection of a psychometric approach depends on many factors. Researchers should justify their evaluation method and consider the intended audience. If the instrument is being developed for descriptive purposes and on a restricted budget, a cursory examination of the CTT-based psychometric properties may be all that is possible. In a high-stakes situation, such as the development of a patient-reported outcome instrument for consideration in pharmaceutical labeling, however, a thorough psychometric evaluation including IRT or RMT should be considered, with final item-level decisions made on the basis of both quantitative and qualitative results.

Is the Give Youth a Voice questionnaire an appropriate measure of teen-centred care in paediatric oncology: a Rasch measurement theory analysis.

BACKGROUND: Adolescents have their own views about the cancer care they receive and how they feel they are treated, but their opinions are rarely solicited. OBJECTIVE: To determine whether the 56-item Give Youth a Voice (GYV-56), its subscales and its 20-item short-form, are clinically meaningful and psychometrically sound instruments that can be used to measure teen-centred care (TCC) in paediatric oncology. DESIGN: Qualitative interviews and a questionnaire survey. SETTING AND PARTICIPANTS: Qualitative interviews with 38 childhood cancer survivors. GYV-56 data collected from 200 paediatric cancer patients and survivors. MAIN OUTCOME MEASURE: The GYV-56, which measures the following four aspects of service delivery: Supportive and respectful relationships; Information sharing and communication; Supporting independence; and Teen-centred services. RESULTS: Qualitative data provided broad support for the TCC conceptual framework and GYV-56 items. After post-hoc reduction of the response options from 7 to 3 (to correct for disordered thresholds), fit to the Rasch model was good, most items showed acceptable fit residuals and chi-square P-values, scale reliability were supported and item locations defined a continuum for TCC that was well-targeted to the sample. By calibrating the items for each subscale and the short-form to the full scale, the scores obtained on each measure are directly comparable. CONCLUSION: Our study found initial support for use of the GYV with a reduced response option format for examining TCC in the adolescent oncology patients. in this paediatric population. Further research using the GYV is needed to elaborate upon our findings.

Emotional vitality in caregivers: application of Rasch Measurement Theory with secondary data to development and test a new measure.

OBJECTIVE: To describe the practical steps in identifying items and evaluating scoring strategies for a new measure of emotional vitality in informal caregivers of individuals who have experienced a significant health event. DESIGN: The psychometric properties of responses to selected items from validated health-related quality of life and other psychosocial questionnaires administered four times over a one-year period were evaluated using Rasch Measurement Theory. SETTING: Community. SUBJECTS: A total of 409 individuals providing informal care at home to older adults who had experienced a recent stroke. MAIN MEASURES: Rasch Measurement Theory was used to test the ordering of response option thresholds, fit, spread of the item locations, residual correlations, person separation index, and stability across time. RESULTS: Based on a theoretical framework developed in earlier work, we identified 22 candidate items from a pool of relevant psychosocial measures available. Of these, additional evaluation resulted in 19 items that could be used to assess the five core domains. The overall model fit was reasonable (χ(2) = 202.26, DF = 117, p = 0.06), stable across time, with borderline evidence of multidimensionality (10%). Items and people covered a continuum ranging from -3.7 to +2.7 logits, reflecting coverage of the measurement continuum, with a person separation index of 0.85. Mean fit of caregivers was lower than expected (-1.31 ±1.10 logits). CONCLUSION: Established methods from the Rasch Measurement Theory were applied to develop a prototype measure of emotional vitality that is acceptable, reliable, and can be used to obtain an interval level score for use in future research and clinical settings.

Adapting a self-efficacy scale to the task of teaching scientific reasoning: collecting evidence for its psychometric quality using Rasch measurement.

Besides teachers' professional knowledge, their self-efficacy is a crucial aspect in promoting students' scientific reasoning (SR). However, because no measurement instrument has yet been published that specifically refers to self-efficacy beliefs regarding the task of teaching SR, we adapted the Science Teaching Efficacy Belief Instrument (STEBI) accordingly, resulting in the Teaching Scientific Reasoning Efficacy Beliefs Instrument (TSR-EBI). While the conceptual framework of the TSR-EBI is comparable to that of the STEBI in general terms, it goes beyond it in terms of specificity, acknowledging the fact that teaching SR requires very specific knowledge and skills that are not necessarily needed to the same extent for promoting other competencies in science education. To evaluate the TSR-EBI's psychometric quality, we conducted two rounds of validation. Both samples (N1 = 114; N2 = 74) consisted of pre-service teachers enrolled in university master's programs in Germany. The collected data were analyzed by applying Rasch analysis and known-group comparisons. In the course of an analysis of the TSR-EBI's internal structure, we found a 3-category scale to be superior to a 5-category structure. The person and item reliability of the scale proved to be satisfactory. Furthermore, during the second round of validation, it became clear that the results previously found for the 3-category scale were generally replicable across a new (but comparable) sample, which clearly supports the TSR-EBI's psychometric quality. Moreover, in terms of test-criterion relationships, the scale was also able to discriminate between groups that are assumed to have different levels of self-efficacy regarding teaching SR. Nonetheless, some findings also suggest that the scale might benefit from having the selection of individual items reconsidered (despite acceptable item fit statistics). On balance, however, we believe that the TSR-EBI has the potential to provide valuable insights in future studies regarding factors that influence teachers' self-efficacy, such as their professional experiences, prior training, or perceived barriers to effective teaching.

Can the ABILHAND handle manual ability in MS?

BACKGROUND: Hand dysfunction is common in multiple sclerosis (MS). Recent interest has focused on incorporating patient-reported outcome (PRO) instruments into clinical trials. Nevertheless, examinations are rare in MS of existing manual ability measures. OBJECTIVES: The objective of this paper is to evaluate the 23-item ABILHAND, developed for use after stroke, in people with MS, comparing the findings from two psychometric approaches. METHODS: We analysed ABILHAND data from 300 people with MS using: 1) traditional psychometric methods (data completeness, scaling assumptions, reliability, internal and external construct validity); and 2) Rasch measurement methods (including targeting, item response category ordering, data fit to the Rasch model, spread of item locations, item scoring bias, item stability, reliability, person response validity). RESULTS: Traditional psychometric methods implied ABILHAND was reliable and valid in this sample. Rasch measurement methods supported this finding. The three-category scoring function worked as intended and item fit to Rasch model expectations was acceptable. The 23 items (location range -3.16 to +2.73 logits) mapped a continuum of manual ability. Reliability was high (Person Separation Index (PSI) = 0.95). CONCLUSION: Both psychometric evaluations supported ABILHAND as a robust manual ability PRO measure for MS. Rasch measurement methods were more informative and, consistent with its role of detecting anomalies, identified ways of advancing further ABILHAND's measurement performance to reduce any potential for type II errors in clinical trials.