Validation of a patient-reported outcome measure for giant cell arteritis.

OBJECTIVES: GCA is systemic vasculitis manifesting as cranial, ocular or large vessel vasculitis. A prior qualitative study developed 40 candidate items to assess the impact of GCA on health-related quality of life (HRQoL). This study aimed to determine final scale structure and measurement properties of the GCA patient reported outcome (GCA-PRO) measure. METHODS: Cross-sectional study included UK patients with clinician-confirmed GCA. They completed 40 candidate items for the GCA-PRO at times 1 and 2 (3 days apart), EQ-5D-5L, ICECAP-A, CAT-PROM5 and self-report of disease activity. Rasch and exploratory factor analyses informed item reduction and established structural validity, reliability and unidimensionality of the final GCA-PRO. Evidence of validity was also established with hypothesis testing (GCA-PRO vs other PRO scores, and between participants with 'active disease' vs those 'in remission') and test-retest reliability. RESULTS: The study population consisted of 428 patients: mean (s.d.) age 74.2 (7.2), 285 (67%) female; 327 (76%) cranial GCA, 114 (26.6%) large vessel vasculitis and 142 (33.2%) ocular involvement. Rasch analysis eliminated 10 candidate GCA items and informed restructuring of response categories into four-point Likert scales. Factor analysis confirmed four domains: acute symptoms (eight items), activities of daily living (seven items), psychological (seven items) and participation (eight items). The overall scale had adequate Rasch model fit (χ2 = 25.219, degrees of freedom = 24, P = 0.394). Convergent validity with EQ5D-5L, ICECAP-A and Cat-PROM5 was confirmed through hypothesis testing. Internal consistency and test-retest reliability were excellent. CONCLUSION: The final GCA-PRO is a 30-item, four-domain scale with robust evidence of validity and reliability in measuring HRQoL in people with GCA.

Development and validation of a patient reported experience measure for experimental cancer medicines (PREM-ECM) and their carers (PREM-ECM-Carer).

BACKGROUND: Our aim was to develop a validated Patient Reported Experience Measure (PREM) to capture patient and carer experience during participation in experimental cancer medicine trials (ECM): called PREM-ECM. METHODS: Mixed method design, consisting of four stages. Questionnaire items were produced for both patients and carers using interviews, focus groups, and cognitive interviews with patients and carers separately. For both patient and carer PREMs, a cross-sectional questionnaire study was conducted to identify final items for inclusion using hierarchical item reduction and Rasch analysis. Questionnaire validity and reliability were assessed, including administration feasibility. RESULTS: Initial interview participants suggested the need for three PREMs, two specific to patients: (i) a 'prior' questionnaire that captured experiences of trial introduction, screening, consenting, and early trial experience (< 6 weeks post consent); and (ii) 'on-trial' that captured experiences of ongoing consent and trial participation; and (iii) a PREM specific for carers. The draft 25-item 'prior' questionnaire was completed by 162 patients and 162 patients completed the draft 35-item 'on-trial' questionnaire. Hierarchical and Rasch analysis produced a 14-item 'prior' list and a 15-item list for 'on-trial'. Both patient PREM's demonstrated a good fit to the Rasch model following Bonferroni correction (X2p = 0.008). The carer 34-draft item questionnaire was completed by 102 participants. Hierarchical and Rasch analysis produced a 13-item list for PREM-ECM-Carer, with good fit to the Rasch model ( X2p = 0.62). The pilot testing demonstrated the feasibility of all the PREMs in capturing patient and caregiver experiences in routine clinical settings. CONCLUSIONS: The three PREM-ECM questionnaires will be the first validated experience measures for ECM trial patients and their carers. These questionnaires may be used to assess patients' and their carers' experiences of ECM and enable robust comparisons across cancer trial units highlighting areas for service improvement.

Improving outcome measures in late onset Pompe disease: Modified Rasch-Built Pompe-Specific Activity scale.

BACKGROUND AND PURPOSE: The Rasch-Built Pompe-Specific Activity (R-PAct) scale is a patient-reported outcome measure specifically designed to quantify the effects of Pompe disease on daily life activities, developed for use in Dutch- and English-speaking countries. This study aimed to validate the R-PAct for use in other countries. METHODS: Four other language versions (German, French, Italian, and Spanish) of the R-PAct were created and distributed among Pompe patients (≥16 years old) in Germany, France, Spain, Italy, and Switzerland and pooled with data of newly diagnosed patients from Australia, Belgium, Canada, the Netherlands, New Zealand, the USA, and the UK and the original validation cohort (n = 186). The psychometric properties of the scale were assessed by exploratory factor analysis and Rasch analysis. RESULTS: Data for 520 patients were eligible for analysis. Exploratory factor analysis suggested that the items separated into two domains: Activities of Daily Living and Mobility. Both domains independently displayed adequate Rasch model measurement properties, following the removal of one item ("Are you able to practice a sport?") from the Mobility domain, and can be added together to form a "higher order" factor as well. Differential item functioning (DIF)-by-language assessment indicated DIF for several items; however, the impact of accounting for DIF was negligible. We recalibrated the nomogram (raw score interval-level transformation) for the updated 17-item R-PAct scale. The minimal detectable change value was 13.85 for the overall R-PAct. CONCLUSIONS: After removing one item, the modified-R-PAct scale is a valid disease-specific patient-reported outcome measure for patients with Pompe disease across multiple countries.

Selecting PedsQL items to derive the PedsUtil health state classification system to measure health utilities in children.

BACKGROUND: There is a lack of preference-based health-related quality of life (HRQoL) measures that consistently value health across a full range of child age groups. The PedsQL is a generic HRQoL instrument validated for children 2-18 years, but it is not preference-based. The objective of this study was to derive the PedsUtil health state classification system from the PedsQL as a basis for a preference-based HRQoL measure for children. METHODS: A two-step process was used to select PedsQL items to include in the health state classification system: 1) exclude poorly functioning items according to Rasch analysis in each of the previously established seven dimensions of the PedsUtil health state classification system and 2) select a single item to represent each dimension based on Rasch and psychometric analyses, as well as input from child health experts and parents. All secondary analyses were conducted using data from the Longitudinal Study of Australian Children (LSAC). Analyses were stratified by age group (i.e., 2-5 years, 6-13 years, and 14-17 years) to represent the different developmental stages of children and to reflect the study design of the LSAC. Rasch analyses were also performed on five random subsamples for each age group to enhance robustness of results. RESULTS: Twelve items were excluded from the PedsUtil health state classification system after the first step of the item selection process. An additional four items were excluded in the second step, resulting in seven items that were selected to represent the seven dimensions of the PedsUtil health state classification system: Physical Functioning ("participating in sports activity or exercise"), Pain ("having hurts or aches"), Fatigue ("low energy level"), Emotional Functioning ("worrying about what will happen to them"), Social Functioning ("other kids not wanting to be their friend"), School Functioning ("keeping up with schoolwork"), and School Absence ("missing school because of not feeling well"). CONCLUSIONS: The PedsUtil health state classification system was derived from the PedsQL based on several criteria and was constructed to be applicable to children two years and older. Research is ongoing to elicit preferences for the PedsUtil health state classification system to construct the PedsUtil scoring system.

Rasch analysis of the new general self efficacy scale: an evaluation of its psychometric properties in older adults with low vision.

BACKGROUND: While general self-efficacy is known to relate to achievement in many areas, it has rarely been evaluated in individuals with low vision. Here we explore the psychometric properties and targeting of the New General Self Efficacy Scale (NGSES) using Rasch analysis in data collected from older adult clinical trial participants with low vision. METHODS: Participants (n = 121) completed pre-intervention telephone questionnaires (i.e., NGSES, Activity Inventory (AI), Beck Depression Inventory (BDI), SF-36, and the Telephone Interview for Cognitive Status (TICS). Rasch analysis using the Method of Successive Dichotomizations (MSD) was applied to NGSES, AI, and BDI datasets to estimate person and item measures, and ordered rating category thresholds. NGSES infit mean square statistics and standard errors were analyzed to test whether data fit Rasch model requirements, and targeting was assessed by comparing distributions of person and item measures. Multiple linear regression evaluated the influence of participant characteristics on NGSES person measures. RESULTS: There was a significant difference (p = 0.01) in the distributions of NGSES person measures (mean = 0.85, range -2.1-3.2) and item measures (mean = 0, range -1.0-0.72). Infit mean square statistics and standard errors for item and person measures conformed to expectations of the Rasch model. Greater NGSES person measure was related to lower BDI person measure (ß = -0.48, p < 0.0005, 95% CI -0.67--0.28) and higher AI person measure (ß = 0.11, p = 0.047, 95% CI 0.0013 - 0.22) after controlling for cognitive status (TICS). Other variables including SF-36, visual acuity, and patient demographics were not related to NGSES person measure. CONCLUSIONS: While NGSES person measures estimated from a low vision patient population conformed to basic Rasch model requirements, the significant differences in the person and item measure distributions indicate poor NGSES targeting, specifically a ceiling effect. Therefore, there is limited discrimination between persons at the upper end of the scale. While further work can evaluate how self-efficacy may be associated with other factors in the low vision patient population, the ceiling effect found in this study cautions interpretation of NGSES results for those with high general self-efficacy. TRIAL REGISTRATION: Pre-registered on clinicaltrials.gov, identifier NCT04926974.

A scoping review to create a framework for the steps in developing condition-specific preference-based instruments de novo or from an existing non-preference-based instrument: use of item response theory or Rasch analysis.

BACKGROUND: There is no widely accepted framework to guide the development of condition-specific preference-based instruments (CSPBIs) that includes both de novo and from existing non-preference-based instruments. The purpose of this study was to address this gap by reviewing the published literature on CSPBIs, with particular attention to the application of item response theory (IRT) and Rasch analysis in their development. METHODS: A scoping review of the literature covering the concepts of all phases of CSPBI development and evaluation was performed from MEDLINE, Embase, PsychInfo, CINAHL, and the Cochrane Library, from inception to December 30, 2022. RESULTS: The titles and abstracts of 1,967 unique references were reviewed. After retrieving and reviewing 154 full-text articles, data were extracted from 109 articles, representing 41 CSPBIs covering 21 diseases or conditions. The development of CSPBIs was conceptualized as a 15-step framework, covering four phases: 1) develop initial questionnaire items (when no suitable non-preference-based instrument exists), 2) establish the dimensional structure, 3) reduce items per dimension, 4) value and model health state utilities. Thirty-nine instruments used a type of Rasch model and two instruments used IRT models in phase 3. CONCLUSION: We present an expanded framework that outlines the development of CSPBIs, both from existing non-preference-based instruments and de novo when no suitable non-preference-based instrument exists, using IRT and Rasch analysis. For items that fit the Rasch model, developers selected one item per dimension and explored item response level reduction. This framework will guide researchers who are developing or assessing CSPBIs.

Measurement of visual functioning following first and second eye cataract surgery using Vision-Related Activity Limitation Item Bank.

PURPOSE: This study aims to compare visual functioning (VF) after first or second eye cataract surgery using the vision-related activity limitation (VRAL) item bank. METHODS: This prospective, interventional study included 787 patients (mean age, 58.2 years) with cataract undergoing cataract surgery (first eye surgery with/out ocular comorbidity, second eye surgery with/out ocular comorbidity) at a tertiary eye care center, South India, who were administered the item bank pre- and at 6 weeks postoperatively to assess change in VF. Rasch analysis was used to estimate VF at both time points, and responsiveness to cataract surgery was calculated as effect size (ES) which was interpreted as small (≤ 0.2), moderate (0.3-0.7), and large (≥ 0.8). RESULTS: Mean best-corrected logMAR VA in surgical eye improved significantly postoperatively compared to preoperative VA (0.20 ± 0.40 vs. 1.19 ± 0.96; P < 0.0001) across all groups. Patients reported significant and large improvements in VF postoperatively across all groups: largest ES for first eye surgery without comorbidity (1.87 [95% CI, 1.61, 2.13]) and smallest for second eye without ocular comorbidity (1.55 [95% CI, 1.22, 1.88]). Compared to patients undergoing second eye surgery, first eye surgery patients reported significantly lower VF preoperatively (-0.72 ± 2.39 vs. 0.17 ± 2.34 logits; P < 0.0001), and a larger change in VF postoperatively (3.71 ± 2.33 logits vs. 4.27 ± 2.83 vs.; P = 0.004). CONCLUSIONS: Cataract surgery resulted in large and significant improvements in VF, regardless of ocular comorbidity and first or second eye surgery. The VRAL item bank is a useful tool to measure responsiveness to cataract surgery.

Development and psychometric evaluation of the adjuvant endocrine therapy beliefs scale for breast cancer survivors.

PURPOSE: Adjuvant endocrine therapy has a vital role in reducing breast cancer mortality. The beliefs in adjuvant endocrine therapy is a very important factor in the medication adherence of breast cancer survivors. Therefore, it is necessary to develop a standardized scale for assessment of adjuvant endocrine therapy. The purpose of this study was to identify the attributes of adjuvant endocrine therapy beliefs, and to evaluate adjuvant endocrine therapy beliefs scale psychometric properties. METHODS: A hybrid model was applied to identify the concept of adjuvant endocrine therapy beliefs and measurement question were developed by the scale development process. Statistical analysis using validity analysis and Rasch analysis based on item response theory were performed. A total of 228 breast cancer survivors in South Korea participated in the study. RESULTS: The finally developed adjuvant endocrine therapy beliefs scale consisted of 22 items. The items extracted by 4 factors explained 59.72% of the total variance. The model fit showed an acceptable level. The adjuvant endocrine therapy beliefs scale was excellent in convergent and discriminant validity with reliability. CONCLUSION: This scale is expected to be practical and useful in identifying adjuvant endocrine therapy beliefs and developing intervention strategies to promote adjuvant endocrine therapy adherence. In addition, continuous education and support should be accompanied so that breast cancer survivors can maintain positive beliefs in adjuvant endocrine therapy adherence.

Chinese version of the Physical Resilience Scale (PRS): reliability and validity test based on Rasch analysis.

BACKGROUND: Physical resilience is known to minimize the adverse outcomes of health stressors for older people. However, validated instruments that assess physical resilience in older adults are rare. Therefore, the purpose of this study was to translate the Physical Resilience Scale (PRS) into Chinese and to validate its psychometric properties in a population of community-dwelling older adults following SARS-CoV-2 infection. METHODS: This study used a cross-sectional design and translated the Physical Resilience Scale into Chinese. A total of 426 older adults who had recovered from SARS-CoV-2 infection were chosen for assessment through convenience sampling. The measurement data were analyzed using the Rasch analysis. RESULTS: Rasch analysis indicates that the Physical Resilience Scale demonstrates excellent reliability, validity, and unidimensionality. The Infit MNSQ and Outfit MNSQ of each entry were 0.77 ~ 1.19, and the degree of fit of each entry to the scale was good. Person and item separation reliability support the internal consistency of the studied samples and PRS items. CONCLUSIONS: The Physical Resilience Scale has good reliability and is suitable for the assessment of physical resilience tests in older people. However, the overall difficulty of the scale is not suitable for older adults of all ability ranges, and it is possible to add higher and lower difficulty items and adjust the difficulty spacing between items in a later study.

Cross-cultural adaptation and validation of the caregiver self-efficacy in contributing to patient self-care scale in China.

BACKGROUND: Caregiver self-efficacy is crucial in improving patient outcomes and caregiver well-being, but there is a lack of suitable scales to assess this concept within the context of Chinese culture. This study aimed to cross-culturally translate the Caregiver Self-Efficacy in Contributing to Patient Self-Care (CSE-CSC) Scale and evaluate its psychometric properties using classical test theory and item response theory. METHODS: The CSE-CSC scale was adapted using Brislin's translation model after obtaining authorization from the original author. A multicenter, cross-sectional study was conducted to assess the psychometric properties of this scale. Classical test theory was used to evaluate reliability (internal consistency, test-retest reliability), validity (content validity, structural validity, convergent validity), and floor and ceiling effects. Item response theory was employed to assess the fit of the rating scale model, reliability, item difficulties, and measurement invariance. RESULTS: The translation and cultural adaptation process was completed. Classical test theory demonstrated good internal consistency (Cronbach's α = 0.935) and test-retest reliability (ICC from 0.784 to 0.829, p<0.001). The I-CVI and K* of each item ranged from 0.875 to 1.00 and 0.871 to 1.00. The first-order 2-factor model fit well (χ2/df = 3.71, RMSEA = 0.082, SRMR = 0.032, CFI = 0.973, TLI = 0.60). Convergent validity showed that the CSE-CSC scores had a strong positive correlation with three separate scales of the CC-SC-CII. There was no floor and ceiling effect in this scale. Rasch analysis showed that the CSE-CSC scale demonstrated a good fit to the rating scale model and exhibited excellent reliability (person/item separation index>2, person/item reliability coefficients>0.8). The Wright map showed that item difficulty matched the respondents' measured abilities. The analysis of differential item functioning (DIF) showed that all items were comparable in gender. CONCLUSIONS: This study indicated that the CSE-CSC scale had good reliability, validity, difficulty degree, and measurement invariance. The CSE-CSC scale can be used to measure caregiver self-efficacy of Chinese patients with multiple chronic conditions.

Rasch Analysis of the Chinese Version of the Nociception Coma Scale-Revised in Patients with Prolonged Disorders of Consciousness.

OBJECTIVES: The aim of this study was to analyze the Chinese version of the Nociception Coma Scale-Revised in patients with prolonged disorders of consciousness within the framework of Rasch modeling, including investigating the invariance of total scores across different etiologies of disorders of consciousness. DESIGN: Prospective psychometric study. PARTICIPANTS: Patients with prolonged disorders of consciousness from the Rehabilitation and Neurology units in hospital. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The Nociception Coma Scale-Revised was undertaken by trained raters and the Coma Recovery Scale-Revised was used to assess patients' consciousness. The psychometric properties within the Rasch model including item-person targeting, reliability and separation, item fit, unidimensionality, and differential item functioning were assessed. RESULTS: 84 patients with prolonged disorders of consciousness (mean age 53 years; mean injury 5 months; 42 with Minimally Conscious State and 42 with Unresponsive Wakefulness Syndrome) of 252 observations were enrolled in the study. Through the procedure of repeated assessment and differential item function, a lower item bias Rasch set was purified. The Rasch model assumptions were examined and met, with item reliability and validity meeting the recommended threshold. CONCLUSIONS: The Chinese version of the Nociception Coma Scale-Revised demonstrated unidimensionality, good reliability and separation, and good item fit, but dissatisfied person fit and item-person targeting. The verbal subscale showed a notable discrepancy between person responses and the difficulty of the items, suggesting limited clinical significance.

The Fremantle Back Awareness Questionnaire: cross-cultural adaptation, reliability, and validity of the Italian version in people with chronic low back pain.

BACKGROUND AND AIM: There is evidence to suggest that assessing back-specific altered self-perception may be useful when seeking to understand and manage low back pain (LBP). The Fremantle Back Awareness Questionnaire (FreBAQ) is a patient-reported measure of back-specific body perception that has never been adapted and psychometrically analysed in Italian. Hence, the objectives of this research were to cross-culturally adapt and validate the Italian version of this outcome measure (namely, the FreBAQ-I), to make it available for use with Italians suffering from chronic LBP. METHODS: The FreBAQ-I was developed by forward and backward translation, review by a committee skilled in patient-reported measures and test of the pre-final version to assess its clarity, acceptability, and relevance. The statistical analyses examined: structural validity based on Rasch analysis; hypotheses testing by investigating correlations of the FreBAQ-I with the Roland Morris Disability Questionnaire (RMDQ), a pain intensity numerical rating scale (PI-NRS), the Pain Catastrophising Scale (PCS), and the Tampa Scale of Kinesiophobia (TSK) (Pearson's correlations); reliability by internal consistency (Cronbach's alpha) and test-retest repeatability (intraclass correlation coefficient, ICC (2,1)); and measurement error by determining the minimum detectable change (MDC). After the development of a consensus-based translation of the FreBAQ-I, the new outcome measure was delivered to 100 people with chronic LBP. RESULTS: Rasch analysis confirmed the substantial unidimensionality and the structural validity of the FreBAQ-I. Hypothesis testing was considered good as at least 75% of the hypotheses were confirmed; correlations: RMDQ (r = 0.35), PI-NRS (r = 0.25), PCS (r = 0.41) and TSK (r = 0.38). Internal consistency was acceptable (alpha = 0.82) and test-retest repeatability was excellent (ICC (2,1) = 0.88, 95% CI: 0.83, 0.92). The MDC95 corresponded to 6.7 scale points. CONCLUSION: The FreBAQ-I was found to be a unidimensional, valid, and reliable outcome measure in Italians with chronic LBP. Its application is advised for clinical and research use within the Italian speaking community.

The Participation Assessment with Recombined Tools-Objective (PART-O): measurement properties of the Norwegian version after traumatic brain injury.

OBJECTIVE: To translate and evaluate the validity of the Participation Assessment with Recombined Tools-Objective (PART-O) in a Norwegian context. METHODS: One hundred and twenty persons with TBI with verified intracranial lesions and persistent symptoms lasting more than 2 years, included in a randomized controlled trial, rated their participation using the PART-O at baseline. The PART-O with its three subscales (Productivity, Out and About, and Social Relations) was translated to Norwegian. Descriptive statistics, Cronbach's alpha, Rasch analysis, and correlation analysis were applied. RESULTS: The Rasch analysis indicated a unidimensional construct of PART-O and its subscales (χ2 < 12.69, p > 0.28). The internal consistency was moderate (Cronbach's alpha 0.48-0.52) and there was a need to reduce scaling options for most of the items. The Out and About and Productivity subscales had considerable floor effects. PART-O showed moderate positive correlation to TBI-related quality of life and global functioning. CONCLUSIONS: PART-O and its subscales reflect unidimensional aspects of participation. In the present Norwegian TBI population the original scaling of PART-O was too detailed for all subscales. The floor effects and suboptimal targeting between items and subjects participation level of the Out and About subscale is a matter of concern.

The Perceived Weight Stigma Scale and Weight Self-Stigma Questionnaire: Rasch analysis, confirmatory factor analysis, and network analysis among Chinese adolescents.

OBJECTIVES: The objectives of the present study were to (i) re-evaluate and expand the psychometric properties of two weight stigma instruments-the Perceived Weight Stigma Scale (PWSS) and the Weight Self-Stigma Questionnaire (WSSQ) among a large sample of adolescents using advanced psychometric methods and (ii) examine how the different types of weight stigma (i.e., PWSS and WSSQ) are associated with psychological distress. STUDY DESIGN: Cross-sectional study. METHODS: In September 2023, a cross-sectional survey utilising convenience sampling was used to recruit 9995 adolescents (mean age = 16.36 years [standard deviation = 0.78]; 57.8% males). They completed the PWSS, WSSQ, and a measure on psychological distress. The data were analysed using Rasch analysis, confirmatory factor analysis (CFA), structural equation modelling (SEM), and network analysis. RESULTS: The CFA and Rasch model results showed acceptable psychometric properties regarding factor structure, factor loading, difficulty, and infit and outfit mean squares (except Items 4 and 7 of the PWSS). There was no substantial differential item functioning for any tested items across the sex and weight categories. The CFA and SEM results showed promising validity indices with significant associations between both weight stigma scales and psychological distress (i.e., depression, anxiety, and stress). Network analysis showed inter-variable connectivity between nodes PWSS3 ("People act as if they are afraid of you") and WSSQF7 ("I feel insecure about others' opinions of me"). CONCLUSIONS: Both weight stigma scales had acceptable psychometric properties and were significantly associated with psychological distress, although each assessed different types of weight stigma. This suggests that researchers and clinicians can use these scales to reliably and validly assess weight stigmas among adolescents.

Assessing menopause symptoms in women with traumatic brain injury: the development and initial testing of a new scale.

With greater survival rates after catastrophic injury, more women with traumatic brain injury (TBI) are living longer than ever. However, knowledge about this transition in these women is largely unexamined and there are no scales that have been developed to assess the experience of symptoms. To address this gap, we developed and tested a new scale of menopause symptoms in midlife women with TBI. We selected candidate items from two existing measures based on feedback from focus group discussions with seven women with TBI. Twenty candidate items were tested in cognitive interviews with six women with TBI/1 non-TBI. Then, these were field tested with 221 participants (TBI, n = 68; non-TBI, n = 153) recruited from registries. Rasch analysis and convergent validity testing were used to evaluate the new scale. Results of the Rasch analysis indicate that overall, the scale fits well the Rasch model with evidence for unidimensionality. Differential item functioning indicated that the scale performed equally well for women with and without TBI and distinguished pre- and post-menopausal states. Convergent validity was found in the expected directions. These findings support further development of the new scale to understand the experience of menopause symptoms among women with TBI.

Assessing the Performance of a Nutrition Knowledge Questionnaire With a Low Socioeconomic Status Population Using Rasch Analysis.

Parents and preschool teachers play a key role in shaping children's dietary behaviors. Knowledge of nutrition and healthy dietary choices is a key component to improve dietary habits and reduce the prevalence of obesity and associated co-morbidities. Using valid and reliable instruments is necessary for accurate assessment of knowledge to tailor interventions and measure effectiveness specific to the population of interest. The objectives of this paper are to (1) identify potential gaps in the baseline nutrition knowledge among parents and teachers using a previously validated questionnaire prior to a preschool obesity prevention intervention; and (2) assess the instrument's reliability and construct validity for a low socioeconomic status population using a post hoc Rasch analysis. Participants included 177 parents and 75 teachers who participated in a Head Start intervention study. Knowledge scores, instrument reliability, and item fit and difficulty were assessed using a Rasch analysis; t-tests were used to determine differences in scores between parents and teachers. Parents answered 38% of questions correctly while teachers correctly answered 46% of the questions. Adequate item fit and reliability were indicated for Sections 1 and 2 of the Nutrition Knowledge Questionnaire (NKQ). Section 3 demonstrated less adequate reliability. The items were found to adequately and reliably define the unidimensional measures of the three components of knowledge represented in this instrument, providing evidence of construct validity. However, Rasch measures indicated the NKQ overall was difficult for participants. Recommendations for improving the instrument for nutrition education/intervention and research practice areas related to obesity and obesity-related conditions are addressed.

Rasch analysis of the carpal tunnel syndrome instrument.

BACKGROUND: The carpal tunnel syndrome instrument (CTSI) is the most widely used patient-reported outcome measure (PROM) in carpal tunnel syndrome (CTS). However, CTSI is an ordinal-type questionnaire and might have caused misinterpretations of the PROM between surgical outcomes of CTS (Camitz and extra/open carpal tunnel release). PURPOSE: This study aims to convert the CTSI to an interval scale using Rasch analysis (RA) and evaluate the outcome differences between the original and transformed scales. STUDY DESIGN: Prospective control study. METHODS: Four hundred twenty-four patients with 567 CTSs had been interviewed for CTSI perioperatively and treated with either endoscopic/open carpal tunnel release or Camitz tendon transfer. Each CTSI was analyzed for dimensionality, fit statistics, and a transformation of the ordinal-to-interval scale by RA. We compared the two groups perioperative scores of three CTSI versions (original 11-item, modified 8-item, and transformed 8-item). RESULTS: Based on the RA, the original CTSI was not unidimensional. We identified two dimensions. After removing misfit items, the perioperative course of each score by three versions of each dimension was compared (Repeated 2-factor analysis of variance). The transformed interval scales of CTSI provided different assessments of score changes from the ordinal scale of CTSI analyses. CONCLUSIONS: Original CTSI consisted of ordinal scale items that yielded different conclusions than scores converted to interval scale by Rasch analysis. CTSI should convert into an interval scale after reclassifying dimensionality by Latent Factor Analysis and removing misfit items.

Measuring palliative care self-efficacy of intellectual and developmental disability staff using Rasch models.

OBJECTIVES: The objectives of this study were to evaluate the psychometric properties of a palliative care self-efficacy instrument developed for intellectual and developmental disability (IDD) staff using Rasch analysis and assess the change in palliative care self-efficacy between 2 time points using Rasch analysis of stacked data. METHODS: Staff from 4 nonprofit IDD services organizations in a US Midwestern state (n = 98) answered 11 questions with Likert-style responses at baseline and 1-month follow-up post training. Rasch analysis was performed to examine rating scale structure, unidimensionality, local independence, overall model fit, person and item reliability and separation, targeting, individual item and personal fit, differential item functioning (DIF), and change in palliative care self-efficacy between 2 time points. RESULTS: The rating scale structure improved when 5 response categories were collapsed to 3. With the revised 3 response categories, the instrument demonstrated good psychometric properties. Principal components analysis of Rasch residuals supported the assumption of unidimensionality. Model fit statistics indicated an excellent fit of the data to the Rasch model. The instrument demonstrated good person and item reliability and separation. Gender-related DIF was found in 1 item, and work tenure-related DIF in 3 items. Overall palliative care self-efficacy improved between 2 time points. SIGNIFICANCE OF RESULTS: Rasch analysis allowed for a more thorough examination of this palliative care self-efficacy instrument than classical test theory and provided information on rating scale structure, targeting, DIF, and individual persons and items. These recommendations can improve this instrument for research and practical contexts.

Rasch analysis of Morse Fall Scale among the older adults with cognitive impairment in nursing homes.

This is a cross-sectional study to investigate the efficacy of Morse Fall Scale (MFS) in nursing homes for older adults with cognitive impairment. According to Rasch analysis, the person separation index was 0.95 (person reliability 0.48), and the item separation index was 9.23 (item reliability 0.99). Wright map showed all items can be considered appropriately directed to the older adults, but the items mainly located at both ends with the center missing. Each item was accepted with good infit and outfit statistics with positive PTMEA CORR. values from 0.49 to 0.68. Two items could be significant differential item functioning (DIF) between the two groups of different fall experience in the past year (item 1 and item 3). In conclusion, nursing assistant could adopt MFS to evaluate fall risk of older adults with cognitive impairment, but the risk grades are still not precise enough. In the future, MFS should be explored and refined further.

Rasch analysis of a palliative care self-efficacy instrument for nursing assistants.

This study used Rasch models to evaluate the psychometric properties of a self-efficacy instrument focused on psychosocial aspects of palliative care developed for nursing assistants (NAs). NAs from 6 skilled nursing facilities in Illinois, U.S. (n=102) were divided into intervention and control groups and answered 16 questions at baseline and 1-month follow-up. A total of 84 NAs completed assessments at both times. The rating scale structure improved when 3 instead of 5 response categories were used. After removing 4 items, the instrument demonstrated unidimensionality and local independence. A person-item threshold map indicated a ceiling effect. For the intervention group, 2 items and 1 item became easier and more difficult respectively post-training. With adjustments, the 12-item instrument became an adequate measure of palliative care self-efficacy. By using PCSE-NA as a tool to assess palliative care self-efficacy of NAs, geriatric nurses can identify weaknesses of and ways to improve training for NAs.