Evidence Of Unidimensionality Research Articles

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

ABSTRACT 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.

Which fatigue scale should I use? A Rasch analysis of two fatigue scales in inflammatory conditions

Abstract Objectives This study aimed to assess the psychometric properties of two widely used fatigue scales in a sample of patients with inflammatory conditions. Methods Rasch analysis was used to examine scale reliability, item bias, unidimensionality and overall fit to the Rasch model. Subtest methodology was utilized to attempt to improve model fit for the Chalder Fatigue Scale (CFQ) and Bristol Rheumatoid Arthritis Fatigue Multidimensional Questionnaire (BRAF-MDQ). Results Initial analysis displayed strong reliability (person separation index 0.89–0.96) alongside a lack of item bias in both scales. However, evidence for unidimensionality was not found for either scale. Overall fit to the Rasch model was marginal for the CFQ and misfitting for the BRAF-MDQ. Local dependency was observed as well as significant item misfit for both scales. Subtest modifications resulted in the best model fit for the BRAF-MDQ [χ2(16) = 15.77, P = 0.469] and the CFQ [χ2(25) = 15.49, P = 0.929]. Modifications resulted in improved fit, reductions in measurement error and the production of ordinal-to-interval conversion tables for both scales. Conversion tables apply the benefits of enhanced measurement accuracy, valid comparison of BRAF-MDQ and CFQ scores to other interval-level data, appropriate use in parametric statistics and enhanced precision in clinical cut-off scores—without the need to change administration format. Conclusion The BRAF-MDQ and CFQ are valid, reliable tools for fatigue assessment. Psychometric indices and content factors suggest the CFQ is suited to measuring general fatigue, particularly when response burden is a concern, while the BRAF-MDQ should be used in clinical presentations where other symptoms are severe and the impact of fatigue on daily living and emotional and social well-being is of interest.

ASSESSMENT OF THE PSYCHOMETRIC PROPERTIES OF ATTITUDE TOWARDS ASSESSMENT TEST (ATAT)

This study is on the assessment of the psychometric properties of Attitude Towards Assessment Test (ATAT). Four research questions guided the study. An instrumentation research design was adopted. The population consisted of secondary school students in Delta State, Nigeria. The sample size comprised 1,000 students, selected through simple random and non-probability cluster sampling techniques. The test under assessment was developed by Megbele, et al. (2023). The Rasch Rating Scale Model was used to answer research 1, which assessed person and item reliability, item statistics, and ordering of response categories. Two fit indices including the infit and outfit mean square (MNSQ) statistics were used to answer research question 2. The data that were used to answer research questions 1 and 2 were analysed with the aid of the Jmetrik IRT software. The Categorical Confirmatory Factor Analysis (CCFA) was used to answer research question 3 while Chi-Square Goodness of Fit Statistics was used to answer research question 4 on construct validity, evidence of unidimensionality, and local independence respectively. The findings of this study revealed that the three components of the scale had high values of item separation index and reliability as well as an acceptable range of Person separation index and reliability; the difficulty index of items in the test was within an acceptable range; Each of the components of the Attitude Towards Assessment Test (ATAT) (Cognitive, affective and behavioural) had one construct each, which is evidence of unidimensionality for the different components of the Attitude Towards Assessment Test. Based on the findings of the study, it was concluded that all items in the different components that made up the test are reliable, have adequate item difficulty infit, and outfit MNSQ estimates, with evidence of unidimensionality and local independence assumptions. The study recommended that the test can be used by examination bodies for the assessment of students in the affective domain.<p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/soc/0011/a.php" alt="Hit counter" /></p>

The Columbia-suicide severity rating scale: validity and psychometric properties of an online Spanish-language version in a Mexican population sample.

The aim of this study was to evaluate the validity and psychometric properties in a Mexican sample of a Spanish-language online version of the Columbia-Suicide Severity Rating Scale (C-SSRS). Data were collected between May and October 2021 from 3,645 participants aged 18 years and over, who agreed to complete the questionnaire. Reliability analysis, confirmatory factor analysis (CFA), and psychometric properties were calculated using a two-parameter model. The results showed a reasonable level of reliability with a Cronbach's alpha of 0.814, and evidence of unidimensionality, and construct validity for suicide risk at three risk levels: low, medium, and high. Analysis of the items suggests that they are consistent with the proposed theoretical model. Our results also demonstrate that the parameters are stable and able to efficiently discriminate individuals at high risk of suicide. We propose the use of this version of the C-SSRS in the Spanish-speaking population, since it is a multifactorial assessment of suicide risk and the inclusion of other clinical and risk factor assessments for a more comprehensive evaluation.

The Revised American Occupational Therapy Association Fieldwork Performance Evaluations: Evaluation of Internal Structure, Response Processes, and Precision-Part 2.

There is an evidence-based need to assess the validity and reliability/precision of the revised American Occupational Therapy Association's Fieldwork Performance Evaluation (FWPE) items for the occupational therapy student (OTS) and the occupational therapy assistant student (OTAS). To evaluate evidence of validity in relation to response processes, internal structure, and precision of the FWPEs. Cross-sectional study design. OTS and OTAS fieldwork practice settings, United States. Two hundred sixty-seven fieldwork educators participated in total, providing 228 OTS evaluations and 39 OTAS evaluations. A Rasch model was used to evaluate aspects of validity and precision. The rating scales provided evidence of the tools' overall validity. Thirty-two of 37 items on the FWPE for the OTS, and 27 of 31 items on the FWPE for the OTAS demonstrated acceptable fit, but the evidence of unidimensionality in the subscales and in the total scales was not fully supported. The total/reduced FWPE scales were able to separate students into at least four distinct groups of fieldwork performance. The relationships between the current and revised FWPEs indicate that the new scales measure different but related constructs of student fieldwork performance, compared with the current version. The findings support that the revised FWPEs for the OTS and OTAS demonstrate preliminary evidence of internal structure, response processes, and precision, supporting evidence-based practice in fieldwork evaluations. What This Article Adds: This article highlights evidence demonstrating the validity and precision of the revised American Occupational Therapy Association's Fieldwork Performance Evaluation items and supports academic and fieldwork settings for occupational therapy students and occupational therapy assistant students.

Mental Health and Well-being Measures for Mean Comparison and Screening in Adolescents: An Assessment of Unidimensionality and Sex and Age Measurement Invariance.

Adolescence is a period of increased vulnerability for low well-being and mental health problems, particularly for girls and older adolescents. Accurate measurement via brief self-report is therefore vital to understanding prevalence, group trends, screening efforts, and response to intervention. We drew on data from the #BeeWell study (N = 37,149, aged 12-15) to consider whether sum-scoring, mean comparisons, and deployment for screening were likely to show bias for eight such measures. Evidence for unidimensionality, considering dynamic fit confirmatory factor models, exploratory graph analysis, and bifactor modeling, was found for five measures. Of these five, most showed a degree of non-invariance across sex and age likely incompatible with mean comparison. Effects on selection were minimal, except sensitivity was substantially lower in boys for the internalizing symptoms measure. Measure-specific insights are discussed, as are general issues highlighted by our analysis, such as item reversals and measurement invariance.

Establishing conversion of the 16-item Informant Questionnaire on Cognitive Decline in the Elderly scores into interval-level data across multiple samples using Rasch methodology.

The 16-item Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE-16) is a well-validated and widely-used measure of cognitive changes (CCs) among older adults. This study aimed to use Rasch methodology to establish psychometric properties of the IQCODE-16 and validate the existing ordinal-to-interval transformation algorithms across multiple large samples. A Partial Credit Rasch model was employed to examine psychometric properties of the IQCODE-16 using data (n=918) from two longitudinal studies of participants aged 57-99 years: the Older Australian Twins Study (n=450) and the Canberra Longitudinal Study (n=468), and reusing the Sydney Memory and Ageing Study (MAS) sample (n=400). Initial analyses indicated good reliability for the IQCODE-16 (Person Separation Index range: 0.82-0.90). However, local dependency was identified between items, with several items showing misfit to the model. Replicating the existing Rasch solution could not reproduce the best Rasch model fit for all samples. Combining locally dependent items into three testlets resolved all misfit and local dependency issues and resulted in the best Rasch model fit for all samples with evidence of unidimensionality, strong reliability, and invariance across person factors. Accordingly, new ordinal-to-interval transformation algorithms were produced to convert the IQCODE-16 ordinal scores into interval data to improve the accuracy of its scores. The findings of this study support the reliability and validity of the IQCODE-16 in measuring CCs among older adults. New ordinal-to-interval conversion tables generated using samples from multiple independent datasets are more generalizable and can be used to enhance the precision of the IQCODE-16 without changing its original format. An easy-to-use converter has been made available for clinical and research use.

The Ego Resiliency Scale-Revised: Confirmatory Factor Analysis and Rasch Models

This study examined the psychometric properties of the Ego Resiliency Scale-Revised (ER89-R). Though support exists for a multidimensional conceptualisation using classical test theory approaches (i.e., a higher-order model comprising Openness to Life Experiences and Optimal Regulation factors), this measure has not been subjected to Rasch analysis. Accordingly, this paper evaluated the higher-order model via confirmatory factor analysis (CFA) before assessing Openness to Life Experiences and Optimal Regulation components using Rasch analysis. CFA, using a general population sample ( N = 2009), supported the higher-order factor structure. Openness to Life Experiences and Optimal Regulation scales met Rasch model assumptions. Specifically, good item/person fit and item/person reliability, and evidence of unidimensionality. Moreover, most items displayed gender invariance. Overall, findings supported the higher-order conceptualisation of the ER89-R, and indicated that the Openness to Life Experiences and Optimal Regulation scales are relatively useful measures of ego resiliency components in a general population sample.

Norms According to Age and Gender for the Spanish Version of the Inventory of Depression and Anxiety Symptoms (IDAS-II).

Inventory of Depression and Anxiety Symptoms-II (IDAS-II) constitutes a useful measurement tool with demonstrated psychometric properties that is contributing to the advancement of knowledge of emotional disorders within transdiagnostic models. To implement its use in clinical settings it is important that the scores can be interpreted in order to guide clinical decisions. This study aims to develops normative data for the Spanish version of the IDAS-II. An anonymous online survey was applied to 1,072 subjects, recruited through a stratified random sampling procedure taking into account population gender, age, and geographical region of Spain. Results show that women tend to score higher than men, particularly on the Dysphoria, General Depression, Appetite Gain, and Lassitude scales. Largest effect sizes for differences in the scores according to age were found for Lassitude, Dysphoria, and General Depression. Therefore, normative data according to gender and age group for each IDAS-II scale is provided. The norms provided in this work complement those already available, facilitating the decision-making of clinical professionals. Evidence of unidimensionality is provided for the 19 IDAS-II scales that allows researchers and clinicians to use specific IDAS-II scales independently.

Development and validity assessment of a Japanese version of the Exercise Adherence Rating Scale in participants with musculoskeletal disorders

BackgroundExercise adherence is important for achieving a long-term effect from musculoskeletal management. The Exercise Adherence Rating Scale (EARS), which was developed in 2017 as a patient reported outcome measure to assess exercise adherence in those with chronic low back pain in the UK, has demonstrated acceptable validity and reliability and is a robust measure of exercise adherence. This study aimed to undertake cross-cultural adaptation of the EARS into Japanese and investigate its structural validity in participants with musculoskeletal disorders.MethodsThe current study was composed of two phases, where a provisional Japanese version of the EARS was developed employing an international guideline for cross-cultural adaptation (Phase A), and structural validity was then evaluated using the Rasch analysis (Phase B). Participants with musculoskeletal disorders who have individualized home exercises prescribed by a physical therapist were recruited.ResultsIn Phase A, the pilot testing was conducted twice because the initial testing detected some uncertainty revealed in comments from 17 participants (5 males and 12 females, 18–79 years of age) about which activities and exercises were supposed to be included. We therefore modified the draft by identifying a person who prescribed/recommended activities and exercises as per the Working Alliance Inventory. The second pilot testing using this draft recruited 30 participants (6 males and 24 females, 18–79 years of age), who provided no further comments, demonstrating the Japanese version of the EARS (EARS-J) had been successfully developed. In Phase B, data from 200 participants who completed the EARS-J (63 males and 127 females, mean ± SD of age = 53.6 ± 17.0) were analyzed using the Andrich's Rating Scale Model. Rasch statics indicated unidimensionality of the six items of the EARS-J. The Cronbach α was 0.77. Substantial ceiling effect (21.0%) was observed, with no floor effect (0.5%).ConclusionsA Japanese version of the EARS has been developed, which demonstrated acceptable structural validity with the evidence of unidimensionality in the Rasch analysis in Japanese people with musculoskeletal disorders who were prescribed individualized home exercises. However, there was a substantial ceiling effect and further studies are required to comprehensively establish validity and reliability of the EARS-J.

A Rasch analysis of the self-administered Foot Health Assessment Instrument (S-FHAI)

BackgroundReliable and valid measurement is the foundation of evidence-based practice. The self-administered Foot Health Assessment Instrument (S-FHAI) was recently developed to measure patients’ evaluations of their own foot health. Evidence regarding the psychometric properties of the S-FHAI is limited. The aim of this study was to investigate those properties by using a Rasch analysis.MethodsThis methodological study analysed secondary data that was collected from nurses (n = 411) in 2015. The psychometric properties of the S-FHAI were evaluated using the Rasch model. Unidimensionality was analysed first, followed by item functioning, person misfit and differential item functioning (DIF).ResultsThe S-FHAI demonstrated evidence of unidimensionality, with an acceptable item fit according to the Rasch model. Person fit and person separation were low, however, indicating restricted separation among different respondents. Item separation was high, demonstrating clear discrimination between the items. No DIF was detected in relation to gender, but significant DIF was demonstrated in relation to age for 6 of the 25 items.ConclusionsThe S-FHAI has potential for use in investigating self-reported foot health. The Rasch analysis revealed that the psychometric properties of the instrument were acceptable, although some issues should be addressed to improve the scale. In future, it may be beneficial to analyse the sensitivity of the items and to test the S-FHAI in more diverse patient populations.

Development and validation of behavioral intention measures of an E-vapor product: intention to try, use, dual use, and switch

BackgroundThe harm caused by tobacco use is primarily attributable to cigarette smoking. Switching completely to non-combustible products may reduce disease risks in adult cigarette smokers who are unable or unwilling to quit. Before a new tobacco product can enter the market or can be marketed as a modified risk tobacco product, the manufacturer must determine the impact that the product will have on the likelihood of changes in tobacco use behavior among both tobacco users and nonusers. One way to estimate change in tobacco use behavior is to assess tobacco users’ and nonusers’ behavioral intentions toward the product and its marketing, including intentions to try, use, dual use, and switch to the product from cigarettes. The purpose of this study was to develop and validate behavioral intention metrics appropriate for use with current, former, and never adult tobacco users.MethodsPreliminary items were subjected to cognitive testing with adult (1) smokers planning to quit cigarettes in the next 30 days, (2) smokers not planning to quit cigarettes in the next 30 days, (3) e-vapor users, (4) former tobacco users, and (5) never tobacco users. Items were iteratively revised based on feedback during cognitive testing, and surviving items were administered to a large sample of adults (N = 2943) representing the aforementioned sub-groups. Rating scale functioning, reliability, validity, bias, and ability to detect change were evaluated.ResultsExamination of the response category thresholds generated by the Rasch model provided evidence that the rating scales were functioning appropriately. Results revealed good stability and excellent internal consistency and person reliability and provided evidence of unidimensionality and convergent validity. Estimates of reliability and validity were similar across sub-groups. A cross-validation sample generally confirmed findings from the validation sample. No items were discarded due to differential item function. Exploratory analyses provided support for ability to detect change.ConclusionsResults from this rigorous, empirical evaluation using large validation and cross-validation samples provide strong support for the psychometric properties of the Intention to Try, Use, Dual Use, and Switch scales with current, former, and never adult tobacco users.

Investigating Psychometric Properties of the Self-Compassion Scale Using Rasch Methodology

The 26-item Self-Compassion Scale (SCS) and its short 12-item version (SCS-SF) were reported to have acceptable psychometric properties, and both scales are widely used to assess self-compassion in individuals. However, recent investigations were inconsistent regarding factor structure of the SCS, and psychometric properties of the scale were not tested for consistency with principles of fundamental measurement using appropriate methodology such as Rasch analysis. A partial credit Rasch model was used to evaluate psychometric properties of the SCS and SCS-SF with the sample of 743 respondents randomly divided into two equal subsamples (A and B) to replicate the results for the purpose of robustness. Initially, there were no misfitting items but the local dependency between various items affected Rasch model fit. This issue was resolved by combining locally dependent items into four super-items resulting in the best fit to the Rasch model of both SCS and SCS-SF, with evidence of unidimensionality and an excellent sample targeting. Although both scale versions had strong reliability satisfactory for individual and group assessment, the original SCS demonstrated superior psychometric properties reflected by higher reliability indicated by Person Separation Index (PSI) of 0.90 compared to the SCS-SF (PSI = 0.85). These analyses were replicated with the sample B for both scale versions, resulting in equally good fit. This permitted generating ordinal-to-interval conversion tables based on Rasch model estimates. The current study supported the reliability and internal validity of both the SCS and SCS-SF. Accuracy of these assessment instruments can be further improved by using the ordinal-to-interval conversion tables published here.

Propriedades Psicométricas do Personality Inventory for DSM-5 (PID-5) em Amostras Brasileiras

Abstract This study aimed to investigate the psychometric properties of the Personality Inventory for DSM-5 (PID-5) in Brazilian community and clinical samples. This research included 1,210 people, 554 of them with psychopathology indicators. The participants answered the PID-5 and the Self-Reporting Questionnaire, in addition to a sociodemographic and health data questionnaire that included the six items of the suicidality module of the Mini International Neuropsychiatric Interview. The results showed that the 25 facets of the PID-5 had adequate reliability coefficients and evidence of unidimensionality. The instrument’s five-factor structure was replicated with high levels of congruence with the representative sample from North America. PID-5 scores were statistically different between clinical and community groups and were positively correlated with measures of suicide risk and psychopathological symptoms. This study presents the psychometric properties of PID-5 and its suitability for use in the Brazilian population.

An investigation of the measurement properties of the de Morton Mobility Index for measuring mobility capacity in hospital patients with Parkinson’s disease

Objective: To examine the measurement properties of the de Morton Mobility Index (DEMMI), a performance-based clinical outcome assessment of mobility capacity, in hospital patients with Parkinson’s disease. Design: Cross-sectional study. Participants: Hospital patients with Parkinson’s disease. Main outcome measure(s): Structural validity and unidimensionality (Rasch analysis), construct validity, internal consistency reliability, and inter-rater reliability of the de Morton Mobility Index (scale range: 0–100 points) were established. The minimal detectable change, the 95% limits of agreement and possible floor and ceiling effects were calculated to indicate interpretability. Results: We analysed validity (n = 100; mean age: 70 years; 71% male) and reliability (n = 47; mean age: 71 years; 68% male) in two samples. The mean Hoehn and Yahr stage was 3.2 and the mean disease duration was 12 years in both samples. Rasch analysis indicated unidimensionality with an overall fit to the model (chi-square = 21.49, P = 0.122). Seventy-three percent of hypotheses on construct validity were confirmed. Internal consistency reliability (Cronbach’s alpha = 0.91) and inter-rater reliability (intraclass correlation coefficient = 0.88; 95% confidence interval: 0.80 to 0.93) were sufficient. The minimal detectable change with 90% confidence was 17.5 points and the limits of agreement were 31%. No floor or ceiling effects were observed. The mean administration time was 6.6 minutes. Conclusion: This study provides evidence of unidimensionality, sufficient internal consistency reliability, inter-rater reliability, construct validity, and feasibility of the de Morton Mobility Index in hospital patients with Parkinson’s disease. Trial registration: German Clinical Trials Register (DRKS00004681). Registered May 6, 2013.

Development and initial validation of the Hopelessness Inventory for Later Life (HILL)

Objectives Hopelessness is associated with depression, physical illness, and mortality. It is a key risk factor for suicidality in later life. Limitations have been identified in available hopelessness assessment measures regarding their use with older adults. The current study describes the development and initial psychometric evaluation of a content-valid, self-report scale for late-life hopelessness (i.e. the Hopelessness Inventory for Later Life; HILL). Methods A sample of 265 older adults (ages 60–99, M = 71.1, SD = 6.7) was recruited through a combination of in-person, online, and mailed solicitations. Participants completed a survey battery containing the preliminary HILL and measures of related constructs (e.g. depression, anxiety, suicide risk, social support) to examine its psychometric properties. Results Multiple analytic item selection strategies resulted in two viable versions of the scale: the HILL and the HILL-Shortened (HILL-S). Both exhibited strong item response characteristics and preliminary evidence of unidimensionality (via factor analysis), internal consistency (α = .96 and α = .89, respectively), and construct validity (via correlations with related constructs). Conclusion Findings provide preliminary psychometric support for both the HILL and HILL-S. Advantages for use of the HILL and the HILL-S over existing measures of hopelessness are discussed.

Validation of the patient activation measure in patients at discharge from hospitals and at distance from hospital care in Sweden

BackgroundThe Patient Activation Measure (PAM) is a recognized measure of how active patients are in their care, and has been translated into several languages and cultural contexts. Patient activity, self-care, and health literacy have become increasingly important aspects of health care, and thus reliable measures of these are needed. However, a Swedish translation of PAM is currently lacking. The aim of the study was to translate and assess the validity and reliability of the Swedish PAM-13.MethodsA self-report questionnaire was handed out to 521 patients at ten medical, geriatric, and surgical wards, and one Virtual Health Room. The Rasch model was employed, using the partial credit model, to assess the functioning of the PAM scale, item fit, targeting, unidimensionality, local independence, differential item functioning (DIF), and person-separation index. Evidence of substantive, content, structural, and external validity was examined.ResultsOf the 521 patients who were consecutively handed a questionnaire, 248 consented to participate, yielding a response rate of 47.6%. The average measure for each category advanced monotonically. The difficulty of the PAM items ranged from − 1.55 to 1.26. The infit and outfit values for the individual items were acceptable. Items 1, 2, and 4 showed disordered thresholds. The mean person location was 1.48 (SD = 1.66). The person-item map revealed that there were no item representations at the top of the scale. The evidence for unidimensionality was ambiguous and response dependency was seen in some items. DIF was found for age. The person separation index was 0.85.ConclusionThe Swedish PAM-13 was reliable, but was not conclusively found to represent one underlying construct. It seems that the Swedish PAM-13 lacks strong evidence for substantive, content, and structural validity. Although valid and reliable measures of ability for activation in self-care among patients are highly warranted, we recommend further development of PAM-13 before application in everyday clinical care.

The Trauma and Suicide Potential Index–5: Psychometric Evaluation in College Samples

We provide a brief description of the development of the Trauma and Suicide Potential Index–5 (TSPI-5) and report on the psychometric properties of scores from the new instrument. The TSPI-5 is designed to assess an individual’s desire to attempt suicide due to experiencing a trauma. We examined the structure of the instrument in two independent undergraduate samples. Study 1 (N = 415) examined the structure of the TSPI-5 using exploratory structural equation modeling. Study 2 (N = 538) reexamined the instrument structure using the same modeling strategy and also examined other validity estimates. Study 1 demonstrated an adequate fit to the sample data (χ2 [1, N = 415] = 215.99, p < .001, comparative fit index (CFI ) = .969, Tucker-Lewis non-normed fit index (TLI) = .939, root mean squared error of approximation (RMSEA) = .319 [90% confidence interval (CI) = .283, .356], p < .001) and suggested evidence for unidimensionality. Study 2 confirmed the unidimensionality of the TSPI-5 as shown by acceptable fit estimates to the sample data, χ2 (5, N = 538) = 80.45, p < .001, CFI = .996, TLI = .99, RMSEA = .17 (90% CI = .140, .200), p < .001. Scale reliability estimates for the TSPI-5 were good in Study 1 (omega = .94) and Study 2 (omega = .96). The TSPI-5 is a brief unidimensional instrument and its scores demonstrated good reliability and validity for assessing suicide-related behaviors due to experiencing a trauma in undergraduate samples.

Validation of the WHOQOL-BREF and Shorter Versions Using Rasch Analysis in Traumatic Brain Injury and Orthopedic Populations

ObjectiveTo use Rasch analysis to validate the World Health Organization Quality of Life-BREF (WHOQOL-BREF) and existing short versions in individuals with traumatic brain injury and orthopedic injuries, with comparisons to a general population group. DesignThe Partial Credit Rasch model was applied to evaluate the WHOQOL-BREF as well as shortened versions using a cross-sectional study design. SettingRegional hospital, and national electoral sample in New Zealand. ParticipantsIndividuals with traumatic brain injury (n=74), individuals with orthopedic injuries (n=114), general population (n=140). InterventionsNone. Main Outcome MeasureWHOQOL-BREF. ResultsThe WHOQOL-BREF met expectations of the unidimensional Rasch model and demonstrated good reliability (person separation index [PSI] =0.82) when domain items were combined into physical-psychological, social, and environmental superitems. Analysis of shorter versions, the EUROHIS-QOL-8 and World Health Organization Quality of Life-5 (WHOQOL-5), indicated overall acceptable fit to the Rasch model and evidence of unidimensionality. The EUROHIS-QOL-8 showed good reliability (PSI=0.81); however, reliability of the WHOQOL-5 (PSI=0.68) was below acceptable standards for group comparisons, in addition to demonstrating poor person-item targeting. ConclusionsThe WHOQOL-BREF and the 8-item EUROHIS-QOL-8 version are both reliable and valid in the assessment of quality of life in both injury and general populations. Ordinal-interval conversion tables published for these validated scales as well as for the WHOQOL-5 can be used to improve precision of assessment. The transformation of ordinal scale scores into an interval measure of health-related quality of life also permits the calculation of a single summary score for the WHOQOL-BREF, which will be useful in a wide range of clinical and research contexts. Further validation work of the WHOQOL-5 is needed to ascertain its psychometric properties.

Confirmation of the unidimensional structure of the Oral Health Literacy Adults Questionnaire

The Oral Health Literacy Adults Questionnaire (OHL-AQ) was designed to test functional oral health literacy in general populations. Exploratory analyses suggested a unidimensional structure rather than the four constructs proposed (reading comprehension, numeracy, listening and decision-making). The purpose of this study was to conduct a confirmatory analysis of the OHL-AQ. A cross-sectional study design used a stratified multistage sampling strategy in 22 districts of Tehran, Iran. The OHL-AQ was administered verbally in its original Persian language. Confirmatory analyses replicated the previous exploratory analyses to determine dimensionality and internal consistency. Data were then randomly assigned to two data sets and item analyses were performed to test reliability. Evidence of unidimensionality was confirmed as the exploratory factor analysis could replicate previous results in a different population. In a confirmatory factor analysis, model fit indicators were mixed because chi-square results were statistically significant and the standard root mean square residual (SRMR) neared guideline values. The comparative fit index (CFI) and the Tucker-Lewis index (TLI) did not meet recommended values but the root mean square error of approximation (RMSEA) was well within standards. Both score validity and reliability were adequate. While findings overall support that OHL measured using the OHL-AQ can be considered unidimensional and therefore OHL can be characterised with one score, further dimensionality studies are needed to investigate populations in which OHL is low.