Test Of Theory Research Articles

Constraints on Einstein-dilaton Gauss-Bonnet gravity with Taiji

In the 2030s, space-based gravitational-wave (GW) detectors will exhibit unprecedented sensitivity in the millihertz frequency band, greatly expanding the potential for testing theories of gravity compared to ground-based GW detectors. Inspired by effective string theory, Einstein-dilaton Gauss–Bonnet (EdGB) gravity introduces an extra dilaton scalar field that is directly coupled to higher curvature terms. Here, we investigate the capability of Taiji to constrain the parameters of EdGB gravity by analyzing GWs from massive black hole binaries (MBHBs). We utilize the parameterized post-Einsteinian (ppE) waveform with the leading order EdGB corrections for the inspiral phase of MBHBs. The constraints on the coupling constants are obtained by performing Fisher matrix analysis. With different mass ratios and spins χi\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\chi _i$$\\end{document} at redshifts z=2,3,4,5\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$z=2,3,4,5$$\\end{document}, the 1σ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$1\\sigma $$\\end{document} bounds on the parameter α\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\alpha $$\\end{document} have the same order of magnitude: α∼107\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sqrt{\\alpha }\\sim 10^7$$\\end{document} m.

The relationship between public risk preference and the underuse or overuse of preventive health services in the information age

The underuse or overuse of preventive health services by individuals is an outward behavioural reflection of their attitude towards disease risk, and they are strongly influenced by their information-acquisition ability. Therefore, we try to explore the relationship among the public risk preference, information-acquisition ability and underuse or overuse of preventive health services, in order to provide decision-making basis in the Information Age. The survey surveyed 2,211 respondents aged ≥ 18 in China from September to December 2019. Taking cancer screening as an example, the multiple price list (MPL) test and item response theory (IRT) model were used to measure individual risk preference and information-acquisition ability. The Logit model and Tobit model were used to estimate the relationship between risk preference, information-acquisition ability and underuse or overuse of preventive health services. Risk-seeking individuals were more likely to underuse preventive health services, while risk-averse individuals were more likely to overuse such services. Information-acquisition ability may improve the underuse of preventive health services in risk-seeking individuals but exacerbate the overuse of preventive health services in risk-averse individuals. Among the investigated information channels, the Internet is the most effective way for the public to obtain information. It is necessary to change the public’s incorrect perception of disease risks and risks associated with preventive health services. In the rapid development of the Information Age, improving public information-acquisition ability is a practicable way to correct the negative relationship between risk preference and individuals’ underuse or overuse of preventive health services.

Persistence of Conceptual Errors in First-Year University Physics Course and Its Possible Relationship with Learning Styles

In this work, we study the persistence of some fundamental previous ideas in physics in a group of freshmen at the Universidad Politécnica de Madrid (Spain). For this purpose, we analyze the answers to a questionnaire consisted of 24 multiple-choice items, most of them borrowed from the Force Concept Inventory (FCI). Our study is performed in two different ways by using, on the one hand, classical test theory and, on the other hand, the Pearson product–moment correlation. The survivance of some of the previous ideas at the end of the course is assessed by comparing and critically analyzing the answers of the students to the same test at the beginning and the end of the term. A possible connection with Honey–Alonso learning styles (LS) is also discussed. The results yielded by our study demonstrate the persistence of some of the initial and previous ideas, no matter the students’ previous qualifications or their current LS.

One-step process for debromination and mineralization of tetrabromobisphenol a by a layered double oxide-supported sulfurized nanoscale zero-valent iron under ambient conditions

Tetrabromobisphenol A (TBBPA), currently the most widely used brominated flame retardant, has attracted significant attention. However, traditional methods for deep debromination or mineralization of TBBPA usually include multiple steps and require external oxidants. In this study, we report a complete degradation of TBBPA through a one-step process of only adding a layered double oxide-supported sulfurized nanoscale zero-valent iron (S-nZVI@LDO) under ambient conditions. TBBPA was rapidly removed by S-nZVI@LDO with an efficiency of 95.6 % (10 mg⋅L-1) within 12 h. The kinetic rate constant (0.0035 min−1) was greater when compared with traditional reductants. The produced Br- ion occupied 76.7 % of total Br content, and the concentration of total organic carbon decreased by over 50 %, suggesting a deep debromination and mineralization of TBBPA by S-nZVI@LDO. It is caused by the substantial improvement of electron transfer, O2 adsorption, and hydrophobicity of S-nZVI@LDO facilitating synchronous reductive debromination and O2 activation to produce ·O2– and ·OH, as approved by electrochemical test, O2-TPO analysis, EPR analysis, and density functional theory calculations. The enriched structural S(−II) and enhanced Fe(III)/Fe(II) redox cycling exerted vital roles in maintaining the reduction potential of the composite. The degradation pathways analysis confirmed that debromination-mineralization mechanisms dominated the complete degradation of TBBPA. This study demonstrates the feasibility of the one-step mineralization removal of TBBPA only using S-nZVI@LDO under ambient conditions and offers insight into external oxidant-free in-situ elimination of halogenated persistent organic pollutants in a natural environment.

Cronbach’s Alpha: Genesis, Issues and Alternatives

The most widely used metric for assessing a scale’s reliability is Cronbach’s alpha. Since its introduction in 1951 by Lee Cronbach, it has evolved into the accepted benchmark for scale reliability. A quick search for ‘Cronbach’s alpha’ in Google Scholar yields more than 8 hundred thousand results. By any measure, this is enormous, and the usage of alpha appears to be present in practically every domain of academics. The fact that alpha has been so successful is surprising, as researchers have consistently criticised and have pointed out a plethora of problems with it. For instance, is that Cronbach never suggested alpha as a reliability metric—rather he proposed alpha as an alternative measure for equivalency in a test-retest context. Another issue Cronbach never suggested the lower bound of 0.70 as a benchmark of reliability. However, the lower bound of 0.70 has become the holy grail of scale reliability. Alpha continues to lead all measures of scale reliability despite its numerous issues. This article examines the history of alpha, its derivations based on classical test theory, and its limitations. It then suggests three alternative measures, along with software procedures to calculate them: alpha with confidence interval, omega and greatest lower bound. The purpose of this article is to enable researchers to have a better idea about the limitations of Cronbach’s alpha, and to make them aware of other measures of reliability which are available. It is hoped that this article will help researchers report better and more accurate reliability measures in their research works alongside the alpha.

Improving the ability to discriminate medical multiple-choice questions through the analysis of the competitive examination to assign residency positions in Spain

IntroductionPsychometrics plays a vital role in evaluating educational research, including the analysis of multiple-choice exams. This study aims to improve the discriminatory ability of the “Médico Interno Residente” (MIR) medical exam in Spain, used to rank candidates for specialized healthcare training, through psychometric analysis.MethodsWe analyzed 2,890 MIR exam questions from 2009 to 2021 (totaling 147,214 exams), categorizing them based on methodology and response type. Evaluation employed classical test theory and item response theory (IRT). Classical test theory determined difficulty and discrimination indices, while IRT assessed the relationship between knowledge levels and question performance.ResultsQuestion distribution varied across categories and years. Frequently addressed knowledge areas included various medical specialties. Non-image-associated clinical cases were the easiest, while case-based clinical questions exhibited the highest discriminatory capacity, differing significantly from image-based case or negative questions. High-quality questions without images had longer stems but shorter answer choices. Adding images reduced discriminatory power and question difficulty, with image-based questions being easier. Clinical cases with images had shorter stems and longer answer choices.ConclusionsFor improved exam performance, we recommend using a clinical case format followed by direct short-answer questions. Questions should be of low difficulty, providing clear and specific answers based on scientific evidence and avoiding ambiguity. Typical clinical cases with key characteristic features should be presented, excluding uncertain boundaries of medical knowledge. Questions should have lengthy stems and concise answer choices, minimizing speculation. If images are used, they should be typical, clear, consistent with the exam, and presented within clinical cases using clinical semiotics and propaedeutics.

Chinese version of the simplified psychological flexibility scale-6 (C-Psy-Flex): Study of its psychometric properties from the perspective of classical test theory and network analysis

Existing measures of psychological flexibility have demonstrated certain limitations, highlighting the critical need for the development of a more comprehensive assessment tool that encompasses all facets of psychological flexibility. In response to this necessity, we have developed the 6-item Psychological Flexibility Scale (C-Psy-Flex) as a concise instrument designed to evaluate individuals' psychological flexibility comprehensively. The objective of this study was to assess the reliability and validity of the Psy-Flex among Chinese college students and teachers. A total of 1511 valid responses were collected, and participants completed the Chinese version of the Psy-Flex, along with several other questionnaires. Exploratory factor analysis with 6 factors and 6 items was conducted on Sample 1 (n = 756). Confirmatory factor analysis on Sample 2 (n = 755) demonstrated good fit for a single-factor structure (χ2 = 21.17, df = 8, P < 0.001, CFI = 0.989, TLI = 0.980, RMSEA = 0.047, RMSEA 90% CI [0.023, 0.071], SRMR = 0.020). Measurement invariance testing indicated strict equivalence of the Chinese version of Psy-Flex across different gender and sample groups. Psychological flexibility was significantly positively associated with life satisfaction, indicators of physical and mental health, and value questionnaire scores, and significantly negatively associated with negative emotions (depression, anxiety, stress) and experiential avoidance. Network analysis visualization techniques were used to further confirm the factor structure of the scale, providing additional evidence of the scale's structural consistency and internal coherence. The Chinese version of the psychological flexibility scale demonstrated good internal consistency, with a Cronbach's α coefficient of 0.82, 95% CI [0.810, 0.840], and a McDonald's ω coefficient of 0.83, 95% CI [0.811, 0.841]. Overall, the study found that the Chinese version of the Psychological Flexibility Scale demonstrated good reliability and validity.

Development and validation of the patient-reported outcome for older people living with HIV/AIDS in China (PROHIV-OLD)

BackgroundThe involvement of quality of life as the UNAIDS fourth 90 target to monitor the global HIV response highlighted the development of patient-reported outcome (PRO) measures to help address the holistic needs of people living with HIV/AIDS (PLWHA) beyond viral suppression. This study developed and tested preliminary measurement properties of a new patient-reported outcome (PROHIV-OLD) measure designed specifically to capture influences of HIV on patients aged 50 and older in China.MethodsNinety-three older people living with HIV/AIDS (PLWHA) were interviewed to solicit items and two rounds of patient cognitive interviews were conducted to modify the content and wording of the initial items. A validation study was then conducted to refine the initial instrument and evaluate measurement properties. Patients were recruited between February 2021 and November 2021, and followed six months later after the first investigation. Classical test theory (CTT) and item response theory (IRT) were used to select items using the baseline data. The follow-up data were used to evaluate the measurement properties of the final instrument.ResultsA total of 600 patients were recruited at the baseline. Of the 485 patients who completed the follow-up investigation, 483 were included in the validation sample. The final scale of PROHIV-OLD contained 25 items describing five dimensions (physical symptoms, mental status, illness perception, family relationship, and treatment). All the PROHIV-OLD dimensions had satisfactory reliability with Cronbach’s alpha coefficient, McDonald’s ω, and composite reliability of each dimension being all higher than 0.85. Most dimensions met the test-retest reliability standard except for the physical symptoms dimension (ICC = 0.64). Confirmatory factor analysis supported the structural validity of the final scale, and the model fit index satisfied the criterion. The correlations between dimensions of PROHIV-OLD and MOS-HIV met hypotheses in general. Significant differences on scores of the PROHIV-OLD were found between demographic and clinical subgroups, supporting known-groups validity.ConclusionsThe PROHIV-OLD was found to have good feasibility, reliability and validity for evaluating health outcome of Chinese older PLWHA. Other measurement properties such as responsiveness and interpretability will be further examined.

FACE-Q for Measuring Patient-reported Outcomes after Facial Skin Cancer Surgery: Cross-cultural Validation.

Facial skin cancer and its surgical treatment can affect health-related quality of life. The FACE-Q Skin Cancer Module is a patient-reported outcome measure that measures different aspects of health-related quality of life and has recently been translated into Dutch. This study aimed to evaluate the performance of the translated version in a Dutch cohort using modern psychometric measurement theory (Rasch). Dutch participants with facial skin cancer were prospectively recruited and asked to complete the translated FACE-Q Skin Cancer Module. The following assumptions of the Rasch model were tested: unidimensionality, local independence, and monotonicity. Response thresholds, fit statistics, internal consistency, floor and ceiling effects, and targeting were assessed for all scales and items within the scales. Responsiveness was tested for the "cancer worry" scale. In total, 259 patients completed the preoperative questionnaire and were included in the analysis. All five scales assessed showed a good or sufficient fit to the Rasch model. Unidimensionality and monotonicity were present for all scales. Some items showed a local dependency. Most of the scales demonstrate ordered item thresholds and appropriate fit statistics. The FACE-Q Skin Cancer Module is a well-designed patient-reported outcome measure that shows psychometric validity for the translated version in a Dutch cohort, using classical and modern test theory.

Nonparametric procedure for comparing the performance of divisions of a network organization

To solve the problem of comparative efficiency analysis of branch operations for a small volume of randomly observed data, a non-parametric approach is relevant, since it does not require a probabilistic model of observations. Comparing the results of the non-parametric approach with the results obtained within the traditionally used Gaussian model is also relevant. Additionally, obtaining a consistent comparison of a group (of no less than three) branches is important. Currently, the non-parametric approach and the corresponding comparison with the known results of solving the problem considered in this work obtained within the framework of the normal model are absent. In addition, insufficient attention is paid to the search for methods of obtaining consistent solutions. This work to some extent fills these gaps. This work uses non-parametric statistical methods and theory of simultaneous hypothesis testing to address these problems. This paper proposes a procedure for comparative analysis of the efficiency of several units within a network organization with a small volume of observations based on the Mann–Whitney tests. We carry out a comparison of the results obtained from the proposed non-parametric procedure with results based on extensions of Student’s t-tests. We propose a method for reducing the number of compatibility problems based on the search for an appropriate significance level. We provide an example of a fully consistent comparison of the efficiency of branch operations.

Item Test Analyze of Entrepreneurship Readiness Instrument for Vocational School Students in East Java Indonesia

Vocational High Schools (SMK), recognized as a solution to address unemployment in Indonesia, simultaneously face the challenge of having the highest open unemployment rate (TPT) compared to other educational levels, standing at 10.38%. Enhancing the quality of questions assessing entrepreneurial readiness is a pivotal approach in tackling this issue. Various factors contribute to students' preparedness for entrepreneurship. This study aims to identify these components by surveying 176 respondents. Employing the Entrepreneurial Readiness Test and analyzing it through Classical Test Theory (CTT) and the Rasch Analysis Model, the research revealed that entrepreneurial mental attitude, risk-taking ability, creativity, motivation, and entrepreneurial skills significantly influence students' readiness for entrepreneurship. The analysis yielded IMS (Infit mean-square) scores ranging from 0.88 to 1.17 and OMS (Outfit mean-square) values between 0.86 to 1.35, indicating a fit for all 50 items in the entrepreneurial readiness test.

Item Statistics of Multiple Choice Physics Achievement Test Using Classic Test Theory and Item Response Theory

This study examine the comparability of item statistics generated from the frameworks of classical test theory (CTT) and 2-parameter model of item response theory (IRT). A 40-item Physics Achievement Test was developed and administered to 600 senior secondary school two students, who were randomly selected from 12 senior secondary schools in Taraba State, Nigeria. Results showed that item statistics obtained from both frameworks were relatively similar. However, item statistics obtained from IRT 2-parameter model looked balanced than those from CTT. In addition, for item selection process, IRT 2-parameter model retained more items than CTT model. This result implies that test developers and public examining bodies should integrate IRT model into their test development processes. Through IRT model, test constructors would be able to generate stable items than in the CTT model used at present and at the end, the test scores of examinees will be more reliably estimated.

Item response theory and computer adaptive testing of the sexual knowledge scale of the sexual knowledge and attitude test in a college sample

ABSTRACT Our study addresses the limited availability of well-validated scales for assessing general sexual knowledge among college populations. To fill this gap, we examined the psychometric properties of a 41-item sexual knowledge scale derived from the Sexual Knowledge and Attitudes Test – Adolescents (SKAT-A) in a sample of young adults aged 18–25 (N = 1,291). We employed classical test theory (CTT) procedures, followed by item response theory (IRT) and computerized adaptive testing (CAT), to refine the SKAT-A knowledge scale. Both CTT and IRT analyses identified six items for removal due to poor discrimination and difficulty parameters. A confirmatory factor analysis supported a well-defined unidimensional latent trait of sexual knowledge. The results of CAT simulations using dynamic item administration demonstrated the scale’s measurement precision, with moderate test reliability and relatively low standard errors. On average, there was a 54.3% reduction in the number of items administered without compromising scale reliability. This study concludes that the SKAT-A efficiently assesses a unidimensional trait of sexual knowledge in college-attending young adults. It highlights that only a subset of items from the full test bank is necessary to achieve this, providing a practical and reliable tool for assessing sexual knowledge in this population.

EFAS Score – Validation of Danish Version by the Score Committee of the European Foot and Ankle Society (EFAS)

BackgroundThe Score Committee of the European Foot and Ankle Society (EFAS) developed, validated, and published the EFAS Score in 13 languages. Currently, the Danish version completed data acquisition and underwent further validation. MethodsThe data were collected pre-operatively and post-operatively at a minimum follow-up of 3 months and mean follow-up of 6 months. Item reduction, scale exploration, confirmatory analyses and responsiveness were executed using classical test theory and item response theory. ResultsThe internal consistency was confirmed in the Danish version (Cronbach’s Alpha 0.88). The Standard Error of Measurement (SEM) was 0.31 and is similar to other language versions. Between baseline and follow-up, 77.2% of patients showed an improvement on their EFAS score, with adequate responsiveness (effect size 1.05). ConclusionsThe Danish EFAS Score version was successfully validated in patients with a wide variety of foot and ankle pathologies. All score versions are freely available at www.efas.net.

Theory of Mind and Social Informant Discrepancy in Autism.

When autistic youth are asked to assess their own social skills, they frequently rate themselves more favorably than their parents rate them. The magnitude of this informant discrepancy has been shown to relate to key clinical outcomes such as treatment response. It has been proposed that this discrepancy arises from difficulties with Theory of Mind. Participants were 167 youth 11 to 17years old; 72% male, and their parents. Youth completed self-report measures of social skills and social cognitive tasks, while their parents completed questionnaires regarding social skills. A repeated-measures ANOVA indicated both non-autistic and autistic youth rated themselves more favorably than their parents rated them across all measures. Zero-order correlations revealed that raw differences between parent- and participant-report were negatively correlated with scores on parent-reported Theory of Mind measures. However, polynomial analysis did not indicate interaction effects between parent- and participant-report on any of the measures used. Polynomial regression revealed that increases in parent-reported social skill predicted larger increases in parent-report Theory of Mind at low levels of parent-reported social skill compared to high levels of parent-reported social skill. Participant-report social skills predicted performance on a behavioral Theory of Mind test in a curvilinear fashion, such that the relationship was positive at low levels of participant-reported social skills, but negative at high levels. This study replicates the finding that raw difference score analyses may result in illusory effects that are not supported when using more contemporary analysis methods, and that more complex and subtle relationships between social insight and perspective-taking exist within autistic youth.

Seismic behavior test and plastic hinge theory for HRB500 prefabricated steel reinforcement cage-cast-in-situ concrete columns

An innovative method for constructing concrete columns has been proposed, namely utilizing the hot-forged double-lock mother combined mechanical sleeve connection for the HRB500 prefabricated steel reinforcement cage－cast-in-situ concrete (PRC-CISC) columns. The purpose of this method is to promote the industrialization of steel reinforcement projects and enhance the quality of structural construction. Two traditional reinforced concrete (RC) columns and four PRC-CISC columns were designed for quasi-static tests with design axial compression ratio (ACR) and reinforcement connection methods as parameters. Firstly, the results of the study showed that all specimens exhibited typical flexural failures, with well-rounded hysteresis curves, gradual stiffness degradation in the later stages, good ductility, and energy dissipation. Mechanical sleeve connections had a minor impact on the failure mode of PRC-CISC columns. Increasing the ACR improved the carrying capacity but reduced ductility, narrowed the hinge zone, and increased longitudinal bar stress. The effect of sleeve connection on energy dissipation, stiffness, ductility, and carrying capacity of the specimens was limited, and the overall behavior was stable and controllable. Furthermore, the carrying capacity and stress distribution of core area steel bars in traditional RC columns and PRC-CISC columns were further calculated to assess the differences. Finally, a two-stage plastic hinge calculation theory was formulated, which takes into account the influence of axial pressure, and construction recommendations for two types of PRC-CISC columns were provided.

Semantic-guided fuzzing for virtual testing of autonomous driving systems

Autonomous driving systems (ADS) have achieved spectacular development and have been utilized in numerous safety-critical tasks. Nonetheless, in spite of their considerable advancement, ADS perception components with high complexity and low interpretability often demonstrate unexpected corner-case behaviors. Several real-world accidents involving self-driving cars even lead to fatalities. Before rolling the autonomous vehicles out to the end-users, it is vital to test and guarantee the safety of ADS. As one of the most critical autonomous driving testing techniques, the prevailing virtual testing depends on the tester using tool-specific languages to code traffic simulation programs correctly. However, this process often requires plenty of effort, and it may fail to capture various rare events from complex driving situations that require sophisticated awareness of the surroundings.In this paper, we design and implement a semantic-guided scene fuzzing framework for autonomous driving systems, namely FuzzScene, based on the metamorphic testing theory. It employs driving scenario description language for scenario representation and equips a tree-based mutation strategy to generate tests with proper oracle information. To improve the testing efficiency and detect misbehaviors under different settings, we propose a unique sampling strategy and construct a testing guidance criterion to optimize FuzzScene. We experiment FuzzScene with multiple steering controllers to evaluate its performance on different tasks. The experiment results show that the semantic transformed driving scenarios generated by FuzzScene efficiently detect hundreds of inconsistent behaviors of ADS. Also, the results confirm that FuzzScene can improve steering precision by retraining with the generated scenes.

Assessment and evaluation of prescribing competences: A systematic review and recommendations.

Since assessment of prescribing competence is a key promoter of student learning and achievement, we aim to summarize existing national-level approaches, provide a systematic review of current literature, indicate the frequency of various methodologies, and make recommendations to promote and extend existing practice. Regulatory body websites were accessed for details of national examinations. PubMed, Embase, the Allied and Complementary Medicine, and CINAHL databases were systematically searched in August 2023 for studies in English from Europe, North America, Australia and New Zealand reporting assessment of prescribing competencies among students/practitioners. Additional articles were identified through citation tracking. National approaches are described for several jurisdictions. A total of 20 514 articles were retrieved, of which 54 met the inclusion criteria. Most articles came from the UK, with medical students and qualified doctors most frequently featured. Multiple choice formats were most common, with short answer questions, calculations and scenario-based skills tests also featured. Direct observations of skills through Objective Structured Clinical Examinations and similar methods were less commonly described. Test reliability generally employed Classical Test Theory. Costs of developing and delivering assessments, differential attainment by demographics, and predictive validity were not indicated. We recommend measurement of the predictive validity of prescribing competence assessments, the routine inclusion of performance by demographic characteristics, extension of competence assessments to professions other than medicine, and structured reporting of methods and findings, including costs and cost-effectiveness. Situational judgement tests would be a valuable addition to assessment practices.

A unidimensional short form of the Beck Hopelessness Scale (BHS-7) derived using item response theory

The Beck Hopelessness Scale (BHS) is the most widely used measure of hopelessness, a key psychological construct linked with various mental health outcomes. In clinical settings, the BHS has proven a reliable tool for assessing hopelessness; however, there has been debate regarding the tool’s internal consistency among non-clinical populations. Most studies assessing the dimensionality of the BHS have relied on the use of classical test theory (CTT). The length of the BHS has also prompted concerns over its practicality. The BHS-9 was developed to address these critiques and formulated based on psychiatrically hospitalized adult patients. The current study investigates the dimensionality of the BHS-9 among a non-clinical sample using item response theory (Mokken scale analysis and Rasch) and CTT. The results confirm that the BHS-9 is essentially unidimensional. However, a salient finding was that Item 6 violated invariant item ordering. An exploratory factor analysis of the remaining eight items found that the items accounted for 48.05% of the variance. Further exploratory factor analyses, removing one item at a time, showed that the removal of item 18 would increase variance explained > 50%. The revised BHS-7 was found to be unidimensional and maintained strong internal consistency and criterion-related validity. This revised tool effectively captures the essence of hopelessness among a non-clinical population and presents a more refined option for the assessment of this construct.

Beyond Role Conflict and Ambiguity: A Global Measure of Role Stress among South African School Teachers

Background. Role stress is linked to reduced work performance, diminished organizational commitment, increased intention to leave a job, and negative physical and mental health effects. Given the significant implications of role stress, researchers have sought to understand and quantify the concept. The Role Conflict and Ambiguity (RCA) scales are widely utilized in job stress research as the predominant measurement tools. They were originally conceptualized as consisting of two independent dimensions: role conflict and role ambiguity. Objective. This study advances the validation research of the RCA scales by exploring its dimensionality through Mokken Scale Analysis (MSA) and Classical Test Theory (CTT). Method. South African school teachers responded to the RCA scales, Maslach Burnout Inventory, and Teaching Satisfaction Scale. Confirmatory Factor Analysis (CFA) and MSA were employed for data analysis. Results. The research determined that a second-order model provided the optimal fit, indicating that role ambiguity and role conflict are subordinate dimensions within the overarching construct of role stress. Conclusion. The findings from the CFA and supplementary bifactor indices reinforce the view that the instrument comprises 13 items, which assess a general dimension of role stress along with two sub-dimensions: role conflict and role ambiguity. Such specificity may lead to more effective strategies to mitigate role-related stress, thereby enhancing overall employee well-being, job satisfaction, and organizational productivity.