Psychometric evaluation of the WHOQOL-BREF and its shorter versions for general Thai population: confirmatory factor analysis and Rasch analysis.

PURPOSE: Rasch analysis was employed to validate the World Health Organization Quality of Life-BREF (WHOQOL-BREF) and its existing shorter versions in the general Thai population. METHODS: 1200 respondents were randomly selected to complete the questionnaire. Confirmatory factor analysis (CFA) was employed to test the structure of the WHOQOL-BREF and its shorter versions with the random sub-sample of 900 respondents, while Rasch analysis was performed with a random sub-sample of 300 respondents. RESULTS: The CFA confirmed the factor structure of WHOQOL-BREF and its shorter versions. The Rasch analysis revealed that the WHOQOL-BREF, when a four-domain structure was tested using a subtest approach, achieved acceptable model fit to the Rasch model and met the expectations of unidimensionality with high reliability (PSI = 0.87). Individual domain models were also unidimensional, but reliability of the 3-item social domain was inadequate. While the 8-item EUROHIS-QOL-8 and 5-item WHOQOL-5 achieved an overall acceptable fit and met the expectations of unidimensionality, the reliability of the WHOQOL-5 was below the acceptable threshold (PSI = 0.66). Reliability of the EUROHIS-QOL-8 was satisfactory (PSI = 0.79). CONCLUSIONS: The WHOQOL-BREF is a valid instrument for use in the Thai general population, both as a total score as well as individual subscales. Rasch analysis also supports the use of EUROHIS-QOL-8, but the WHOQOL-5 lacks good reliability. While the reliability of the EUROHIS-QOL-8 is sufficiently high for between-group analysis, the Thai WHOQOL-BREF total score can also be used for within-participant analyses. Rasch investigation with a more varied health conditions of general Thai samples or patient groups is encouraged for future studies.

Development and Validation of a Physical Food Security Tool for Older Adults.

BACKGROUND: Current measures of food insecurity focus on economic access to food, but not on the physical aspect of food insecurity that captures the inability to access food or prepare meals. This is particularly relevant among the older adult population who are at a high risk of functional impairments. OBJECTIVES: To develop a short-form physical food security (PFS) tool among older adults using statistical methods based on the Item Response Theory (Rasch) model. METHODS: Pooled data from adults aged ≥60 y of the NHANES (2013-2018) (n = 5892) were used. The PFS tool was derived from the physical limitation questions included in the physical functioning questionnaire of NHANES. Item severity parameters, fit and reliability statistics, and residual correlation between items were estimated using the Rasch model. The construct validity of the tool was assessed by examining associations with the Healthy Eating Index (HEI)-2015 scores, self-reported health, self-reported diet quality, and economic food insecurity, using weighted multivariable linear regression analysis, controlling for potential confounders. RESULTS: A 6-item scale was developed, which had adequate fit statistics and high reliability (0.62). It was categorized based on raw score severity into high, marginal, low, and very low PFS. Very low PFS was associated with respondent's self-reported poor health (OR = 23.8; 95% CI: 15.3, 36.9; P < 0.0001), self-reported poor diet (OR = 3.9; 95% CI: 2.8, 5.5; P < 0.0001), low and very low economic food security (OR = 6.08; 95% CI: 4.23, 8.76; P < 0.0001), and with lower mean HEI-2015 index score, in comparison to older adults with high PFS (54.5 compared with 57.5, P = 0.022). CONCLUSIONS: The proposed 6-item PFS scale captures a new dimension of food insecurity that can inform on how older adults experience food insecurity. The tool will require further testing and evaluation in larger and different contexts to demonstrate its external validity.

Environmental health knowledge of healthcare professionals: Instrument development and validation using the Rasch model.

INTRODUCTION: environmental risk factors constitute a major public health issue, calling for preventive actions and interventions at multiple levels. An important step in this direction is increasing the environmental health (EH) knowledge of the healthcare professionals. In this context, tools designed to measure such knowledge are of imperative importance. The aim of the present study was to develop an EH knowledge tool for healthcare professionals. METHODS: a group of experts defined the knowledge areas of the EH tool and their corresponding items. An online pilot and a validation study were performed. Internal consistency reliability was measured with the Kuder-Richardson 20 (KR-20) estimate, the construct validity and uni-dimensionality of the tool were assessed with the Rasch model. Known-groups validity was analysed with the two-sample t-test. RESULTS: a total of n = 151 and n = 444 healthcare professionals and end-year medical and nursing students, participated in the pilot and the validation study, respectively. The resulting 33-item EH knowledge questionnaire for healthcare professionals (EHKQ-HP) obtained a KR-20 = 0.82. The scale is uni-dimensional. Its construct validity was verified, and its items cover a wide range of difficulties. Separation statistics were adequate and known-groups behaved as hypothesized. CONCLUSIONS: the EHKQ-HP is a valuable resource for measuring the EH knowledge of the healthcare professionals. As such it will be useful in detecting EH knowledge gaps, and helping public health agents in making informed decisions when developing interventions for increasing this very knowledge. This would consequently help in improving the health of the general population.

A phubbing scale tested in Bangladesh, Iran, and Pakistan: confirmatory factor, network, and Rasch analyses.

BACKGROUND: Phubbing, a phenomenon of ignoring others in face-to-face conversations due to mobile phone use, can be assessed using a Phubbing Scale (PS). Recently, the PS has been shortened into an eight-item version, the PS-8. However, psychometric properties of the PS-8 among Iranian, Bangladeshi and Pakistani individuals remain understudied, especially using advanced psychometric testing, such as Rasch and network analyses. METHODS: Participants residing in Iran, Bangladesh, and Pakistan (n = 1902; 50.4% females; mean age = 26.3 years) completed the PS-8 and the Internet Disorder Scale-Short Form (IDS9-SF) via an online survey. Network analysis was used to examine if PS-8 items were differentiated from IDS9-SF items; confirmatory factor analysis (CFA) was used to examine the factor structure and measurement invariance of the PS-8; Rasch modeling was used to examine the dimensionality of the PS-8 and differential item functioning (DIF). RESULTS: Network analysis showed that PS-8 items were clustered together with a distance to the IDS9-SF items. The CFA results supported a two-factor structure of the PS-8, and the two-factor structure was found to be invariant across countries and women and men. Rasch model results indicated that the two PS-8 subscales were both unidimensional and did not display DIF across countries and gender/sex. CONCLUSION: The PS-8 is a feasible and robust instrument for healthcare providers, especially mental health professionals, to quickly assess and evaluate individuals' phubbing behaviors.

Providing meaningful interpretation of performance outcome measures by co-calibration with patient-reported outcomes through the Rasch model: illustration with multiple sclerosis measures.

Performance outcome (PerfO) measures are based on tasks performed by patients in a controlled environment, making their meaningful interpretation challenging to establish. Co-calibrating PerfO and patient-reported outcome (PRO) measures of the same target concept allow for interpretation of the PerfO with the item content of the PRO. The Rasch model applied to the discretized PerfO measure together with the PRO items allows expressing parameters related to the PerfO measure in the PRO metric for it to be linked to the PRO responses. We applied this approach to two PerfO measures used in multiple sclerosis (MS) for walking and manual ability: the Timed 25-Foot Walk (T25FW) and the 9-Hole Peg Test (9HPT). To determine meaningful interpretation of these two PerfO measures, they were co-calibrated with two PRO measures of closely related concepts, the MS walking scale - 12 items (MSWS-12) and the ABILHAND, using the data of 2,043 subjects from five global clinical trials in MS. The probabilistic relationships between the PerfO measures and the PRO metrics were used to express the response pattern to the PRO items as a function of the unit of the PerfOs. This example illustrates the promises of the co-calibration approach for the interpretation of PerfO measures but also highlights the challenges associated with it, mostly related to the quality of the PRO metric in terms of coverage of the targeted concept. Co-calibration with PRO measures could also be an adequate solution for interpretation of digital sensor measures whose meaningfulness is also often questioned.

Psychometric properties of the Burnout Assessment Tool across four countries.

BACKGROUND: The Burnout Assessment Tool (BAT) is a new burnout measure developed to replace the Maslach Burnout Inventory (MBI). Studies have supported the psychometric properties and cross-cultural measurement invariance of the BAT. However, some unresolved questions remain. These questions are the appropriate level of score interpretation, convergent validity with the MBI, and measurement invariance using sample groups from countries outside of Europe. METHODS: We used a cross-sectional survey approach to obtain 794 participants from Australia (n = 200), the Netherlands (n = 199), South Africa (n = 197), and the United States (n = 198). In brief, we used bifactor modelling to investigate the appropriate score interpretation and convergent validity with the MBI. Hereafter, we used the Rasch model and ordinal logistic regression to investigate differential item functioning. RESULTS: The bifactor model showed a large general factor and four small group factors, which suggests calculating and interpreting a general burnout score. This model further shows that the BAT and MBI measure the same burnout construct but that the BAT is a more comprehensive burnout measure. Most items fit the Rasch model, and few showed non-negligible differential item functioning. CONCLUSIONS: Our results support the psychometric properties and cross-cultural measurement invariance of the BAT in Australia, the Netherlands, South Africa, and the United States. Furthermore, we provide some clarity on the three previously mentioned unresolved questions.

Is the performance at the implicit association test sensitive to feedback presentation? A Rasch-based analysis.

The Implicit Association Test (IAT) is commonly used for the indirect assessment of psychological constructs. While the features of the IAT that might influence the performance of the respondents have been extensively investigated, the effect of informing the respondents about the correctness of their responses (i.e., feedback presentation) has been poorly addressed so far. The study addresses this issue by presenting an across-domain (implicit prejudice and food preference) Rasch-based analysis of IAT data obtained with and without feedback presentation. Results showed that speed was influenced by the interaction between feedback presentation and associative condition, whereas accuracy was influenced by the associative condition. This result varied across-domain. Results suggested that IATs administered with feedback presentation provide more accurate information on the construct of interest.

Validation of a Modified Version of Interpersonal Reactivity Index for Medical Students Using Rasch Analysis.

Construct: Empathy has been accepted to interweave both cognitive aspects (the ability to put oneself in another person's place), and affective (or emotional) aspects, indicating an emotional reaction or response to another person's emotional state. Literature supports the positive influences of empathy on doctor-patient relationship, patient satisfaction, and positive clinical outcomes. Background: Many studies have dealt with the development of empathy measurement tools for physicians and medical students. A frequently used empathy measuring instrument for medical students is the "Interpersonal Reactivity Index" (IRI) which was designed to measure the multi-dimensional aspects of empathy in the general adult population. Most previous literature which validated IRI for medical students has used factor analysis, whilst studies applying Rasch models have been limited. Our study aimed to investigate the psychometric properties of a modified version of IRI for medical students using Rasch analysis. Approach: Medical students (1,293) from 15 medical schools in South Korea participated in an online questionnaire consisting of 28 items of the Korean translated version of IRI. We applied exploratory factor analysis (EFA) using polychoric correlation matrix to determine the optimal number of factors followed by Rasch analysis and McDonald's Omega calculation. Findings: The adapted IRI-MS (IRI for medical students) consisted of 17 items in four dimensions: empathic concern (5), fictitious situation (4), perspective taking (4), and personal distress (4). The overall fit of IRI-MS revealed an acceptable goodness-of-fit for all 17 items and a positive point measure correlation for all items. Reliability indices from the Rasch modeling and McDonald's Omega values of all four dimensions were satisfactory for research. We found the Wright-Andrich maps and category probability curves of the IRI's four dimensions to be less than optimal in measuring empathy levels with adequate precision. Conclusions: Rasch analysis of IRI-MS fell short from being able to prove satisfactory validity in measuring the multidimensional nature of empathy in medical students. However, our study applying Rasch analysis may serve as groundwork for future studies, to further develop from the shortcomings of our findings.Supplemental data for this article are available online at at www.tandfonline.com/htlm .

Utility of a multimodal computer-based assessment format for assessment with a higher degree of reliability and validity.

Multiple choice questions (MCQs) suffer from cueing, item quality and factual knowledge testing. This study presents a novel multimodal test containing alternative item types in a computer-based assessment (CBA) format, designated as Proxy-CBA. The Proxy-CBA was compared to a standard MCQ-CBA, regarding validity, reliability, standard error of measurement, and cognitive load, using a quasi-experimental crossover design. Biomedical students were randomized into two groups to sit a 65-item formative exam starting with the MCQ-CBA followed by the Proxy-CBA (group 1, n = 38), or the reverse (group 2, n = 35). Subsequently, a questionnaire on perceived cognitive load was taken, answered by 71 participants. Both CBA formats were analyzed according to parameters of the Classical Test Theory and the Rasch model. Compared to the MCQ-CBA, the Proxy-CBA had lower raw scores (p < 0.001, η2 = 0.276), higher reliability estimates (p < 0.001, η2 = 0.498), lower SEM estimates (p < 0.001, η2 = 0.807), and lower theta ability scores (p < 0.001, η2 = 0.288). The questionnaire revealed no significant differences between both CBA tests regarding perceived cognitive load. Compared to the MCQ-CBA, the Proxy-CBA showed increased reliability and a higher degree of validity with similar cognitive load, suggesting its utility as an alternative assessment format.

Using a Non-Contact Sensor to Delineate Management Zones in Vineyards and Validation with the Rasch Model.

The production of high-quality wines is one of the primary goals of modern oenology. In this regard, it is known that the potential quality of a wine begins to be determined in the vineyard, where the quality of the grape, initially, and later that of the wine, will be influenced by the soil properties. Given the spatial variability of the fundamental soil properties related to the potential grape production, such as texture, soil organic matter content, or cation exchange capacity, it seems that a uniform management of a vineyard is not the most optimal way to achieve higher grape quality. In this sense, the delineation of zones with similar soil characteristics to implement site-specific management is essential, reinforcing the interest in incorporating technologies and methods to determine these homogeneous zones. A case study was conducted in a 3.3 ha vineyard located near Évora, south of Portugal. A non-contact sensor (DUALEM 1S) was used to measure soil apparent electrical conductivity (ECa) in the vineyard, and later, a kriged ECa map was generated. ECa and elevation maps were utilised to delineate homogeneous zones (management zones, MZs) in the field through a clustering process. MZs were validated using some soil properties (texture; pH; organic matter-OM; phosphorous-P2O5; potassium-K2O; the sum of the exchange bases-SEB; and cation exchange capacity-CEC), which were determined from 20 soil samples taken in the different MZs. Validation was also performed using Rasch measures, which were defined based on the formulation of the objective and probabilistic Rasch model, integrating the information from the aforementioned soil properties at each sampling location. The comparison of the MZs was more evident with the use of the Rasch model, as only one value was to be employed in each MZ. Finally, an additional validation was conducted using a vegetation index to consider the plant response, which was different in each MZ. The use of a non-contact sensor to measure ECa constitutes an efficient technological tool for implementing site-specific management in viticulture, which allows for the improvement of decision-making processes by considering the inherent spatial variability of the soil.

Item-Level Psychometrics of the Meaningful Activity Participation Assessment (MAPA) Scale.

This study investigates the psychometric properties of the Meaningful Activity Participation Assessment-Meaning (MAPA-M) scale using the Rasch measurement model. For the psychometric properties of MAPA-M, principal component analysis, Rasch analysis, and differential item functioning analysis were conducted. Participants in this study were 480 older adults from the USC Well Elderly 2 study, recruited from 21 locations in the Los Angeles metropolitan area. There were eight items with DIF, but they were accepted because they assumed unidimensionality and showed good person invariance. The 25 items assuming unidimensionality of MAPA-M had values between 0.6 and 1.4 in infit and Outfit MnSq, and all ZSTD values were less than 2.0. The 25 items demonstrated a conceptual item-difficulty hierarchy. The person strata value was 2.68, which is equivalent to a reliability index value of .76. The findings indicate that the revised scale can accurately and reliably measure meaningful activities by older adults.

A Bayesian many-facet Rasch model with Markov modeling for rater severity drift.

Fair performance assessment requires consideration of the effects of rater severity on scoring. The many-facet Rasch model (MFRM), an item response theory model that incorporates rater severity parameters, has been widely used for this purpose. Although a typical MFRM assumes that rater severity does not change during the rating process, in actuality rater severity is known to change over time, a phenomenon called rater severity drift. To investigate this drift, several extensions of the MFRM have been proposed that incorporate time-specific rater severity parameters. However, these previous models estimate the severity parameters under the assumption of temporal independence. This introduces inefficiency into the parameter estimation because severities between adjacent time points tend to have temporal dependency in practice. To resolve this problem, we propose a Bayesian extension of the MFRM that incorporates time dependency for the rater severity parameters, based on a Markov modeling approach. The proposed model can improve the estimation accuracy of the time-specific rater severity parameters, resulting in improved estimation accuracy for the other rater parameters and for model fitting. We demonstrate the effectiveness of the proposed model through simulation experiments and application to actual data.

Semi-automated Rasch analysis with differential item functioning.

Rasch analysis is a procedure to develop and validate instruments that aim to measure a person's traits. However, manual Rasch analysis is a complex and time-consuming task, even more so when the possibility of differential item functioning (DIF) is taken into consideration. Furthermore, manual Rasch analysis by construction relies on a modeler's subjective choices. As an alternative approach, we introduce a semi-automated procedure that is based on the optimization of a new criterion, called in-plus-out-of-questionnaire log likelihood with differential item functioning (IPOQ-LL-DIF), which extends our previous criterion. We illustrate our procedure on artificially generated data as well as on several real-world datasets containing potential DIF items. On these real-world datasets, our procedure found instruments with similar clinimetric properties as those suggested by experts through manual analyses.

Objective measurement of Spanish emotion vocabulary.

Current research on emotion knowledge and competence emphasises the role of language. Emotion vocabulary is one of the indicators of emotion knowledge that can be objectively measured; however, the metric properties of the scores obtained in tests and tasks to measure it have seldom been adequate. In this study we designed and validated a Spanish emotion vocabulary test (MOVE) employing a corpus approach to construct cloze multiple-choice items, administered the test to a Spanish-speaking sample from two countries, Spain and Argentina, and analysed structural validity of the test items with the Rasch model measurement approach. Eighty-eight items showed adequate fit. Overall, a substantial percentage of variance was explained by a latent variable. Reliability indexes at the test, item, and person level were also adequate. As a vocabulary test, the MOVE can be used in psychological and neurological investigation, as well as in language learning research.

Psychometric Evaluation of the Spanish Families Importance in Nursing Care: Nurses' Attitudes Scale Through Classical Test Theory and Rasch Analysis.

Nurses' attitudes toward families play an important role in improving relationships with patients' families. It is essential to have valid and reliable instruments to assess nurses' attitudes toward involving families. The aim of this study was to analyze the psychometric properties of the refined Spanish version of the Families' Importance in Nursing Care-Nurses' Attitudes (FINC-NA) according to classical test theory and the Rasch model (N = 263). Cronbach's alpha values were .73 to .87 and intraclass correlation coefficients ranged from .72 to .86. Rasch analysis results suggested that it was a multidimensional scale with four dimensions and a simpler response scheme than the original scale. Except for one item, the scale was free from bias regarding age and experience time. The FINC-NA is a reliable and valid measure showing a good fit to the Rasch model and is ready to map nurses' attitudes and measure the effectiveness of family nursing educational interventions.

Exploring a New Application of Construct Specification Equations (CSEs) and Entropy: A Pilot Study with Balance Measurements.

Both construct specification equations (CSEs) and entropy can be used to provide a specific, causal, and rigorously mathematical conceptualization of item attributes in order to provide fit-for-purpose measurements of person abilities. This has been previously demonstrated for memory measurements. It can also be reasonably expected to be applicable to other kinds of measures of human abilities and task difficulty in health care, but further exploration is needed about how to incorporate qualitative explanatory variables in the CSE formulation. In this paper we report two case studies exploring the possibilities of advancing CSE and entropy to include human functional balance measurements. In case study I, physiotherapists have formulated a CSE for balance task difficulty by principal component regression of empirical balance task difficulty values from Berg's Balance Scale transformed using the Rasch model. In case study II, four balance tasks of increasing difficulty due to diminishing bases of support and vision were briefly investigated in relation to entropy as a measure of the amount of information and order as well as physical thermodynamics. The pilot study has explored both methodological and conceptual possibilities and concerns to be considered in further work. The results should not be considered as fully comprehensive or absolute, but rather open up for further discussion and investigations to advance measurements of person balance ability in clinical practice, research, and trials.

Information from Noise: Measuring Dyslexia Risk Using Rasch-like Matrix Factorization with a Procedure for Equating Instruments.

This study examines the psychometric properties of a screening protocol for dyslexia and demonstrates a special form of matrix factorization called Nous based on the Alternating Least Squares algorithm. Dyslexia presents an intrinsically multidimensional complex of cognitive loads. By building and enforcing a common 6-dimensional space, Nous extracts a multidimensional signal for each person and item from test data that increases the Shannon entropy of the dataset while at the same time being constrained to meet the special objectivity requirements of the Rasch model. The resulting Dyslexia Risk Scale (DRS) yields linear equal-interval measures that are comparable regardless of the subset of items taken by the examinee. Each measure and cell estimate is accompanied by an efficiently calculated standard error. By incorporating examinee age into the calibration process, the DRS can be generalized to all age groups to allow the tracking of individual dyslexia risk over time. The methodology was implemented using a 2019 calibration sample of 828 persons aged 7 to 82 with varying degrees of dyslexia risk. The analysis yielded high reliability (0.95) and excellent receiver operating characteristics (AUC = 0.96). The analysis is accompanied by a discussion of the information-theoretic properties of matrix factorization.

Rasch analysis, reliability, and validity of the Turkish version of the Lumbar Spine Instability Questionnaire.

Background/aim: Lumbar instability is an important condition that can be seen frequently in people with low back pain, affecting both the progression and the choice of appropriate exercise. The Lumbar Spine Instability Questionnaire (LSIQ) is a simple and low-cost tool for evaluating disturbed back stability in people with low back pain. The aim of this study is to develop the Turkish version of the LSIQ (LSIQ-T) and to evaluate its psychometric properties using the Rasch model. Materials and methods: One hundred participants with chronic low back pain completed the LSIQ-T. The LSIQ-T was repeated for 30 participants after 1 week to establish its test-retest reliability. While internal and external construct validity were investigated using Rasch analysis and the Spearman correlation coefficient, respectively, reliability was evaluated in terms of internal consistency by Cronbach's alpha and the Person Separation Index (PSI). Results: All items of the LSIQ-T were found to fit the Rasch model (chi-square: 34.07 (df = 15), p = 0.0033). The internal construct validity was good, the overall mean item fit residual was 0 (SD: 0.765), and the mean person fit residual was 0.322 (SD: 1.123). Internal consistency reliability was low with a PSI of 0.63 although Cronbach's alpha was acceptable (0.68). When the test-retest reliability was examined via differential item functioning (DIF) by time, none of the items showed DIF. Conclusion: The LSIQ-T is a valid unidimensional scale for the Turkish population. Although the LSIQ-T had low internal consistency, it demonstrated unidimensionality and is appropriate for use. Therefore, the LSIQ-T can be used in clinical practice and scientific research.

Transformation of Rasch model logits for enhanced interpretability.

BACKGROUND: The Rasch model allows for linear measurement based on ordinal item responses from rating scales commonly used to assess health outcomes. Such linear measures may be inconvenient since they are expressed as log-odds units (logits) that differ from scores that users may be familiar with. It can therefore be desirable to transform logits into more user-friendly ranges that preserve their linear properties. In addition to user-defined ranges, three general transformations have been described in the literature: the least measurable difference (LMD), the standard error of measurement (SEM) and the least significant difference (LSD). The LMD represents the smallest possible meaningful unit, SEM relates the transformed scale values to measurement uncertainty (one unit on the transformed scale represents roughly one standard error), and LSD represents a lower bound for how coarse the transformed scale can be without loss of valid information. However, while logit transformations are relatively common in the health sciences, use of LMD, SEM and LSD transformations appear to be uncommon despite their potential role. METHODS: Logit transformations were empirically illustrated based on 1053 responses to the Epworth Sleepiness Scale. Logit measures were transformed according to the LMD, SEM and LSD, and into 0-10, 0-100, and the original raw score (0-24) ranges. These transformations were conducted using a freely available Excel tool, developed by the authors, that transforms logits into user-defined ranges along with the LMD, SEM and LSD transformations. RESULTS: Resulting LMD, SEM and LSD transformations ranged 0-34, 0-17 and 0-12, respectively. When considering these relative to the three user-defined ranges, it is seen that the 0-10 range is narrower than the LSD range (i.e., loss of valid information), and a 0-100 range gives the impression of better precision than there is, since it is considerably wider than the LMD range. However, the 0-24 transformation appears reasonable since it is wider than the LSD, but narrower than the LMD ranges. CONCLUSIONS: It is suggested that LMD, SEM and LSD transformations are valuable for benchmarking in deciding appropriate ranges when transforming logit measures. This process can be aided by the Excel tool presented and illustrated in this paper.

Novel insights regarding the measurement properties of the SCOPA-AUT.

BACKGROUND: The Scale for Outcomes in Parkinson's disease for Autonomic symptoms (SCOPA-AUT) is an instrument intended to assess overall and domain-specific autonomic symptom burden. In this study the SCOPA-AUT is translated into Swedish and its measurement properties are assessed. METHODS: Following translation the SCOPA-AUT was field-tested regarding comprehensibility, relevance, and respondent burden (n = 20). It was then tested according to Rasch measurement theory using data from 242 persons with PD, of whom 162 completed SCOPA-AUT at baseline and 1-2 years later, giving a total of 404 data points for analysis. RESULTS: The Swedish SCOPA-AUT took a mean of 6 min to complete and was considered easy to use and relevant by respondents. SCOPA-AUT exhibited acceptable Rasch model fit, represents more severe levels of dysautonomia than that reported by the sample, and response categories were not working as expected for 17 items. Local dependency was identified and followed a pattern resembling the suggested subscales. Accounting for the subscale structure eliminated local dependency and reduced the initially inflated reliability from 0.81 to 0.68. CONCLUSIONS: The SCOPA-AUT is useful as a clinical check-list but requires further developmental work in order to meet more rigorous standards as an outcome measurement instrument.