Differential Item Functioning Analysis Research Articles

The Psychometric Properties of the ITP Life Quality Index Assessed in a Large Multinational “Real-World” Cohort of Immune Thrombocytopaenia Patients

Background Immune Thrombocytopenia (ITP) is an autoimmune disorder caused by immunologic destruction of otherwise normal platelets, most commonly occurring in response to an unknown stimulus. ITP is diagnosed after excluding other possible causes of disease, and symptoms can present across varying severities and treatments. The poor understanding of the symptoms and cause can result in both misdiagnosis and complex treatment patterns, which may significantly affect health related quality of life (HRQoL) in this patient population. There is currently no disease specific prospective tool in routine clinical practice to capture HRQoL in the adult ITP population. To help assess the impact of this condition on HRQOL, the ITP Life Quality Index (ILQI), a 10-item patient-reported outcome (PRO) measure was developed as a tool for clinical practice to aid discussions between patients and physicians about disease experience so to inform patient-centric treatment decisions. The ILQI was originally developed by clinical experts in the field of ITP and content validity was confirmed by conducting qualitative interviews with 15 adult patients with ITP. The ILQI was then cognitively debriefed patients with ITP and items refined following qualitative analysis and additional clinical input. The ILQI was included in the ITP World Impact Survey (I-WISh), a global observational study which collected data on the impact of ITP on patients' HRQoL. This large study provided an opportunity to assess the psychometric properties of the ILQI and confirm the scoring cut-offs. Methods The I-WISh survey resulted in data from 1,507 patients with ITP across 12 countries worldwide and was used to assess the structure, reliability and validity of the ILQI. The structure of the ILQI, how the items fit into total scores and subscales, was assessed by splitting the data into two datasets. One dataset was used for identifying the structure using exploratory factor analysis and one was used for checking the structure using confirmatory factor analysis. Validity, the ability of the ILQI to measure the correct construct, was assessed through known groups and convergent validity methods. Reliability, the consistency of the ILQI items and their ability to create reproducible scores, was assessed via internal consistency methods. To understand whether each ILQI item measured ITP in a similar way across countries, differential item functioning (DIF) was assessed using Cochran-Mantel-Haenszel test and Logistic regression. Finally, existing score cut-offs (20-"significantly impaired QoL"; 30 - "severely impaired QoL") were assessed using receiver operating characteristic (ROC) curves and a simulation study was conducted to develop rules for missing data. Results Results indicated that the ILQI has an essentially unidimensional structure, supporting the creation of a total score including all 10 items. The ILQI items work together to create a reproducible total score, usable for making judgements on an individual patient basis (Omega total and Cronbach's alpha coefficients ≥ 0.90). Known groups methods showed that ILQI monotonically increased with ITP severity (linear trends p's <0.001). Convergent validity methods confirmed hypothesized relationships between ILQI total/item scores and items which measure aspects of HRQOL, suggesting that the ILQI total score and its items measure the same concept of interest (i.e. HRQOL). DIF analyses showed that ILQI item responses were similar between the USA and Western countries. Some uniform DIF was discovered between the USA and other countries, and some non-uniform DIF was found between the USA and China for culturally relevant items as expected. The previous clinical cut-off of 20 for "significantly impaired QoL" was supported, but a cut-off 30 may be too conservative for assessing "severely impaired QoL". Missing data simulation suggests that a total score can be created even when some items are missing. Conclusion The ILQI is a valid and reliable, unidimensional measure to assess HRQoL of patients with ITP. Despite some variations in ILQI item responses between USA and China, adoption of the ILQI in routine care will improve consistency of patient-centric decision making and may lead to better outcomes for those patients whose HRQoL has been affected. The revised cut-off scores for the ILQI developed will also aid patient-centric decision making between patients and physician. Disclosures Griffiths: Adelphi Values Ltd: Employment; Novartis: Consultancy. Grant:Novartis: Consultancy; Adelphi Values Ltd: Employment. Bonner:Adelphi Values Ltd: Employment; Novartis: Consultancy. D'Alessio:Novartis: Employment, Equity Ownership. Hill:Apellis: Honoraria; Bioverativ, a Sanofi company: Honoraria; Novartis: Speakers Bureau; Alexion: Research Funding. Provan:Rigel ONO: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; UCB: Consultancy; MedImunne: Consultancy; ONO Pharmaceutical: Consultancy. Ghanima:Bayer: Honoraria, Research Funding; Amgen: Consultancy, Honoraria; Pfizer/BMS: Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Cooper:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Rigel: Consultancy, Membership on an entity's Board of Directors or advisory committees; Principia: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Viana:Novartis: Employment, Equity Ownership.

Item-level psychometrics of a brief self-reported memory problem screening measure in breast cancer survivors

Background: We previously developed and psychometrically validated a self-reported memory problem (SRMP) measure using principal component analysis. In the present study, we applied item response theory (IRT) analysis to further examined the construct validity and determine item-level psychometric properties for the SRMP.Methods: The sample included 530 female breast cancer survivors (61% non-Hispanic White, mean age = 57 years) who were recruited from community-based organizations and large health care systems. We examined the construct validity, item-level psychometric properties, and differential item functioning (DIF) of the SRMP using confirmatory factor analysis (CFA), IRT and logistic regression analysis models.Results: The CFA confirmed a one-factor structure for the SRMP (comparative fit index [CFI] = 0.996, root-mean-square-error-approximation [RMSEA] = 0.059). As expected, SRMP scores correlated significantly with pain, mood, and fatigue; but not spiritual health locus of control (SPR). DIF analysis showed no measurement differences based on race/ethnicity and age groups.Conclusion: The CFA and DIF analysis supported the construct validity of the SRMP and its use in an ethnically diverse breast cancer population. These findings provide further evidence of the generalizability for the SRMP, and support its utilization as a psychometrically valid and reliable screening measure of cancer and treatment-related memory difficulties.

TESTING THE RELIABILITY AND VALIDITY OF THE RESIDENT SATISFACTION INDEX

Understanding residents’ life satisfaction in assisted living (AL) is essential for creating supportive environments that are targeted toward the needs and desires of residents. Unfortunately, few measures have been developed and tested to evaluate residents’ life satisfaction in AL. The purpose of this study was to test the reliability and validity of the Resident Satisfaction Index (RSI) which was designed to measure residents’ life satisfaction in AL. Baseline data was used from a study testing the Dissemination and Implementation of Function Focused Care in AL. A total of 501 residents from 54 AL facilities were included in the sample. Based on Rasch analysis, there was evidence of internal consistency with an alpha coefficient of 0.95 and validity based on INFIT and OUTFIT statistics which ranged from 0.4 to 1.6. Item mapping showed the easiest item to endorse was item 10 which referred to perceptions of staff’s kindness. The hardest item to endorse was item 17 which asked about staff’s responsiveness to residents’ needs. Differential item functioning (DIF) analysis was done to examine differences in item responses by age, gender, and cognitive status. The measure was equally appropriate for those with and without mild to moderate cognitive impairment and between males and females, 5 out of 22 items were answered differently based on gender. 117 (23%) participants scored so high in satisfaction that they could not be differentiated. Findings support the reliability and validity of the measure although we recommend adding more difficult items to better differentiate between residents.

Psychometric Properties and Differential Item Functioning of a Web-Based Assessment of Children’s Emotion Recognition Skill

Emotion recognition (ER) involves understanding what others are feeling by interpreting nonverbal behavior, including facial expressions. The purpose of this study is to evaluate the psychometric properties of a web-based social ER assessment designed for children in kindergarten through third grade. Data were collected from two separate samples of children. The first sample included 3,224 children and the second sample included 4,419 children. Data were calibrated using Rasch dichotomous model. Differential item and test functioning were also evaluated across gender and ethnicity. Across both samples, we found consistent item fit, unidimensional item structure, and adequate item targeting. Analyses of differential item functioning (DIF) found six out of 111 items displaying DIF across gender and no items demonstrating DIF across ethnicity. The analyses of person measure calibrations with and without DIF items yielded no evidence of differential test functioning (DTF) across gender and ethnicity groups in both samples.

Investigation of Finnish and German 9th grade students’ personal meaning with relation to mathematics

This study focuses on a comparison of personal meanings that students from Finland (FIN) and Germany (GER) assign to (learning) mathematics. Participants are 256 Finnish and 276 German ninth graders. The survey consists of 18 scales that are based on the theory of personal meaning. The original German version was translated into Finnish. Using item response theory (IRT) partial credit models, the psychometric properties of the scales were found to be good. As statistical procedure, Differential Item Functioning (DIF) analysis and mean comparisons were conducted to compare the two groups’ (FIN and GER) responses. Indicators of educational system and curriculum could be found in students’ responses to explain similarities and differences between the two samples. In both countries, social inclusion is meaningful for most of the students (Support by teacher, Experience of relatedness, and Emotional-affective relation to teacher). In addition, it is personally meaningful for Finnish students to do well in mathematics. This shows a link to identity-related questions such as confirming important aspects of the self. Hence, personal meanings related to mathematics are more common in Finland than in Germany (Active practice of mathematics, Cognitive challenge, and Self-perfection).

Psychometric properties of the European Portuguese version of the Perceived Risk of HIV Scale in the general population and HIV-uninfected partners from sero-different couples

BackgroundPerceived risk of HIV plays an important role in the adoption of protective behaviours and HIV testing. However, few studies have used multiple-item measures to assess this construct. The Perceived Risk of HIV Scale (PRHS) is an 8-item measure that assesses how people think and feel about their risk of HIV infection. This cross-sectional study aimed to assess the psychometric properties (reliability and validity) of the European Portuguese version of the PRHS, including the ability of this scale to discriminate between individuals from the general population and HIV-uninfected partners from sero-different couples on their perceived risk of HIV infection (known-groups validity).MethodsThis study included 917 individuals from the general population (sample 1) to assess the psychometric properties of the PRHS. To assess the known-groups validity, the sample comprised 445 participants from the general population who were in an intimate relationship (sub-set of sample 1) and 42 HIV-uninfected partners from sero-different couples (sample 2). All participants filled out a set of questionnaires, which included a self-reported questionnaire on sociodemographic information, sexual behaviours, HIV testing and the PRHS. Sample 1 also completed the HIV Knowledge Questionnaire – 18-item version.ResultsThe original unidimensional structure was reproduced both in exploratory and confirmatory factor analyses, and the PRHS demonstrated good reliability (α = .78; composite reliability = .82). The differential item functioning analyses indicated that the items of the PRHS, in general, did not function differently for men and women or according to HIV testing. Significant associations with sexual risk behaviours and HIV testing provided evidence for criterion validity. The known-groups validity was supported.ConclusionsThe PRHS is a suitable scale in the evaluation of the perceived risk of HIV, and its psychometric characteristics validate its use in the Portuguese population. Furthermore, the present study suggests that interventions improving individuals’ HIV risk perceptions may be important since they were associated with different sexual behaviours and the likelihood of HIV testing.

Using Weighted Sum Scores to Close the Gap Between DIF Practice and Theory

AbstractWe make a distinction between the operational practice of using an observed score to assess differential item functioning (DIF) and the concept of departure from measurement invariance (DMI) that conditions on a latent variable. DMI and DIF indices of effect sizes, based on the Mantel‐Haenszel test of common odds ratio, converge under restricted conditions if a simple sum score is used as the matching or conditioning variable in a DIF analysis. Based on theoretical results, we demonstrate analytically that matching on a weighted sum score can significantly reduce the difference between DIF and DMI measures over what can be achieved with a simple sum score. We also examine the utility of binning methods that could facilitate potential operational use of DIF with weighted sum scores. A real data application was included to show this feasibility.

Improving the Measurement of School Climate Using Item Response Theory

AbstractThe U.S. government has become increasingly focused on school climate, as recently evidenced by its inclusion as an accountability indicator in the Every Student Succeeds Act. Yet, there remains considerable variability in both conceptualizing and measuring school climate. To better inform the research and practice related to school climate and its measurement, we leveraged item response theory (IRT), a commonly used psychometric approach for the design of achievement assessments, to create a parsimonious measure of school climate that operates across varying individual characteristics. Students (n = 69,513) in 111 secondary schools completed a school climate assessment focused on three domains of climate (i.e., safety, engagement, and environment), as defined by the U.S. Department of Education. Item and test characteristics were estimated using the mirt package in R using unidimensional IRT. Analyses revealed measurement difficulties that resulted in a greater ability to assess less favorable perspectives on school climate. Differential item functioning analyses indicated measurement differences based on student academic success. These findings support the development of a broad measure of school climate but also highlight the importance of work to ensure precision in measuring school climate, particularly when considering use as an accountability measure.

Testing Differential Item Functioning in Small Samples

Differential item functioning (DIF) is a pernicious statistical issue that can mask true group differences on a target latent construct. A considerable amount of research has focused on evaluating methods for testing DIF, such as using likelihood ratio tests in item response theory (IRT). Most of this research has focused on the asymptotic properties of DIF testing, in part because many latent variable methods require large samples to obtain stable parameter estimates. Much less research has evaluated these methods in small sample sizes despite the fact that many social and behavioral scientists frequently encounter small samples in practice. In this article, we examine the extent to which model complexity—the number of model parameters estimated simultaneously—affects the recovery of DIF in small samples. We compare three models that vary in complexity: logistic regression with sum scores, the 1-parameter logistic IRT model, and the 2-parameter logistic IRT model. We expected that logistic regression with sum scores and the 1-parameter logistic IRT model would more accurately estimate DIF because these models yielded more stable estimates despite being misspecified. Indeed, a simulation study and empirical example of adolescent substance use show that, even when data are generated from / assumed to be a 2-parameter logistic IRT, using parsimonious models in small samples leads to more powerful tests of DIF while adequately controlling for Type I error. We also provide evidence for minimum sample sizes needed to detect DIF, and we evaluate whether applying corrections for multiple testing is advisable. Finally, we provide recommendations for applied researchers who conduct DIF analyses in small samples.

A Propensity Score Method for Investigating Differential Item Functioning in Performance Assessment.

This study introduces a novel differential item functioning (DIF) method based on propensity score matching that tackles two challenges in analyzing performance assessment data, that is, continuous task scores and lack of a reliable internal variable as a proxy for ability or aptitude. The proposed DIF method consists of two main stages. First, propensity score matching is used to eliminate preexisting group differences before the test, ideally creating equivalent groups as in a randomized experimental study. Then, linear mixed effects models are adopted to perform DIF analysis based on the matched data set. We demonstrate this propensity DIF method using a high-stakes functional English language proficiency test. DIF due to education was investigated in the writing component, which consists of two continuously scored performance-based tasks. Although the proposed method is demonstrated in the context of language testing, it can be applied to other types of performance assessments.

Assessment of Authorial Voice Strength in L2 Argumentative Written Task Performances: Contributions of Voice Components to Text Quality

The purpose of this study was twofold: (a) to examine the level of authorial voice strength among Iranian second language (L2) writers; and (b) to investigate the relationship between L2 learners’ authorial voice strength and the quality of their argumentative written task performances. Argumentative writing samples were elicited from 129 upper-intermediate L2 learners in writing courses. To quantify learners’ voice strength, these samples were scored by two raters using an analytic voice rubric. Raters also provided a holistic rating of the overall authorial voice strength in written argumentations. The quality of argumentations was measured using the TOEFL scoring rubric. While descriptive results indicated that learners demonstrated a low level of voice strength in their argumentations, results from Multiple Regression Analysis (MRA) suggested positive associations between voice strength along with two of its dimensions and the quality of writings. Moreover, results from Multiple Correspondence Analysis (MCA) pointed to the association of low and mid-level of writing quality and low voice strength, and the prevalence of high and mid voice strength in learners with high proficiency in writing. Finally, while an Item Response Theory (IRT) analysis revealed that the ‘presence’ dimension of authorial voice was the most difficult one for L2 learners, a Differential Item Functioning (DIF) analysis showed that the difficulty of the three voice dimensions did not differ significantly across genders. The findings were discussed regarding English L2 writing within the Iranian context.

An Item Response Theory Analysis of the Korean Version of the CRAFFT Scale for Alcohol Use Among Adolescents in Korea

PurposeThis study aimed to validate the psychometric properties of the CRAFFT (Car, Relax, Alone, Forget, Family/Friends, Trouble) by using item response theory (IRT) and further examine gender differences in item-level responses. MethodsThis study used the 13th (2017) Korea Youth Risk Behavior Survey data conducted by the Korean Centers for Disease and Prevention and analyzed data of 8,568 students who reported drinking alcohol in the previous 30 days. IRT assumptions including unidimensionality, local independence, and monotonicity were tested. A one-factor two-parameter IRT model was fitted for item parameterization (M2 = 76.92, 20 df, p < .001, root mean square error of approximation = 0.02). Graphics for item characteristic curves and item and test information curves were provided. Differential item functioning (DIF) analysis was evaluated to measure item equivalence between boys and girls. ResultsUnidimensionality and local independence were satisfied, and the dominant factor eigenvalue and variance were 2.48 and 41.3% in boys and 2.08 and 34.7% in girls, respectively, and residual correlations in paired items were less than .2. The discrimination parameters were estimated as 1.32–3.59 for boys and 1.30–3.64 for girls. The severity parameters estimated verity as −0.23 to 1.67 for boys and −0.32 to 2.17 for girls. DIF was detected for four of six items, “Car,” “Relax,” “Forget,” and “Family/friends.” However, its impact on the total score was negligible. ConclusionThe CRAFFT is a valid and reliable screening tool to identify alcohol use problems for both boys and girls, exhibiting good discrimination, good coverage of severity, and negligible DIF.

A Comparison of Aggregation Rules for Selecting Anchor Items in Multigroup DIF Analysis

AbstractThis study addresses the topic of how anchoring methods for differential item functioning (DIF) analysis can be used in multigroup scenarios. The direct approach would be to combine anchoring methods developed for two‐group scenarios with multigroup DIF‐detection methods. Alternatively, multiple tests could be carried out. The results of these tests need to be aggregated to determine the anchor for the final DIF analysis. In this study, the direct approach and three aggregation rules are investigated. All approaches are combined with a variety of anchoring methods, such as the “all‐other purified” and “mean p‐value threshold” methods, in two simulation studies based on the Rasch model. Our results indicate that the direct approach generally does not lead to more accurate or even to inferior results than the aggregation rules. The min rule overall shows the best trade‐off between low false alarm rate and medium to high hit rate. However, it might be too sensitive when the number of groups is large. In this case, the all rule may be a good compromise. We also take a closer look at the anchor selection method “next candidate,” which performed rather poorly, and suggest possible improvements.

Psychometric properties of a Haitian Kreyòl version of the trauma symptom checklist

BackgroundIn this study, the first to examine psychometrics of a Haitian Kreyòl version of the Trauma Symptom Checklist-40 (TSC-40), we investigated trauma symptoms in survivors of Haiti's 2010 earthquake who reside in Haiti's Cité Soleil slum, a violent neighborhood where non-partner sexual violence (NPSV) is rampant and whose residents are historically underrepresented in research. Methods233 women and 280 men 18 years or older completed the TSC-40. Differential Item Function (DIF) analysis was performed on the TSC-40 responses for women and men. We examined symptom counts by gender, between NPSV victims and non-victims, and by interaction between gender and NPSV experience. ResultsWe identified a reduced pool of 17-items that exhibited no gender bias. This 17-item index showed acceptable internal consistency reliability (α = 0.87). Employing this index, average symptom counts for women (x¯ = 11.3) did not differ from men (x¯= 11.1). Average symptom counts for NPSV victims was greater (x¯ = 12.5) than for non-victims (x¯= 10.7). The gender by experience of NPSV interaction indicated that women victims had the highest symptom counts (x¯=14.0). LimitationsWe used non-probability sampling, and data were from self-reports collected in a cross-sectional survey. ConclusionsObserved differences in trauma burden are likely to be misleading if instruments are administered without regard to DIF. We contribute a Haitian Kreyòl Trauma Symptom 17-item index, which offers clinicians/practitioners in Haiti the opportunity to use a valid and reliable measure of enduring trauma symptoms validated in Haiti.

Successful use of the Unified Dyskinesia Rating Scale regardless of PD- or dyskinesia-duration

ObjectiveWe assessed differential item functioning (DIF) in the Unified Dyskinesia Rating Scale (UDysRS) to evaluate bias risk from the duration of Parkinson's Disease (PD) and duration of dyskinesia. BackgroundAssessing DIF is a core validation step for rating scales. If DIF is present for an item, interpretation must consider influences from the tested covariates. DIF can be uniform or non-uniform, depending on the consistency of influence from the given covariate across all levels of dyskinesia. MethodsUsing a large UDysRS database (N = 2313), uniform and non-uniform DIF related to the duration of PD and/duration of dyskinesia were tested. Unidimensionality of UDysRS was first confirmed using confirmatory factor analysis. DIF analysis was conducted using two independent latent models. DIF in an item was confirmed if both methods independently identified DIF at a significance level using Bonferroni correction. McFadden pseudo R^2 measured clinical relevancy of DIF magnitude (negligible, moderate, and large) for items identified with DIF, and items with DIF were considered clinically relevant if they exceeded a negligible designation. ResultsMost items did not show uniform or non-uniform DIF based on PD and dyskinesia duration in isolation or in combination. For all items where DIF was identified, the magnitude statistic was in the negligible range (McFadden pseudo R^2 < 0.035) and the combined impact of multiple identified DIF items on UDysRS likewise did not exceed the negligible designation. ConclusionThe absence of clinically relevant DIF suggests that the UDysRS can be applied across all patients regardless of their PD- or dyskinesia-duration.

A systematic comparison of three sadism measures and their ability to explain workplace mistreatment over and above the dark triad

The present study investigated a potential antecedent of workplace mistreatment, sadism, which represents the dispositional tendency to engage in cruel, demeaning, or harmful behavior for dominance or pleasure. Time-lagged data from 379 Amazon Mechanical Turk workers showed that sadism positively predicted interpersonal deviance, instigated incivility, and cyberbullying frequency above and beyond the dark triad. Moreover, relative weight analyses consistently identified sadism as the most important predictor of workplace mistreatment compared to other dark triad predictors. This study also sought to identify possible differences among three popular sadism scales. The three scales were interchangeable in terms of predicting the outcomes. Confirmatory factor analyses and differential item functioning analyses both revealed, however, that only the SSIS was invariant across sex groups.

Measurement equivalence of the Four-Dimensional Symptom Questionnaire (4DSQ) in adolescents and emerging adults.

The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report instrument measuring distress, depression, anxiety and somatization. The questionnaire has been developed and validated in adult samples. It is unknown whether adolescents and emerging adults respond to the 4DSQ items in the same way as adults do. The objective of the study was to examine measurement equivalence of the 4DSQ across adolescents, emerging adults and adults. 4DSQ data were collected in a primary care psychotherapy practice (N = 1349). Measurement equivalence was assessed using differential item and test functioning (DIF and DTF) analysis in an item response theory framework. DIF was compared across the following groups: adolescents (age 10–17), emerging adults (age 18–25), and adults (age 26–40). DIF was found in 9 items (out of 50) across adolescents and adults, and in 4 items across emerging adults and adults. The item with the largest DIF was ‘difficulty getting to sleep’, which was less severe for adolescents compared to adults. A likely explanation is that adolescents have a high base rate for problems with sleep initiation. The effect of DIF on the scale scores (DTF) was negligible. Adolescents and emerging adults score some 4DSQ items differently compared to adults but this had practically no effect on 4DSQ scale scores. 4DSQ scale scores from adolescents and emerging adults can be interpreted in the same way as 4DSQ scores from adults.

English

The aim of the study was to examine the psychometric properties and the differential items functioning of short version of Career Aspiration Scale (CAS) in a sample of 2700 of Omani high school students. The results of the total score of CAS showed acceptable internal consistency (Cronbach’s α=0.67). An exploratory factor analysis yielded a support for nine items version identifying single construct. Differential item functioning (DIF) analysis confirmed that there were differences on five items concerning gender. DIF analysis performed according to grade showed that the functioning of CAS items was consistent in both grades except for item four. Suggestions were provided for further psychometric investigation of the scale. Key words: Career aspiration scale, differential functioning, gender, grade

Preservice science teachers’ ecological value orientation: A comparative study between Indonesia and Korea

The current study aimed to examine differences in ecological values between Indonesian and Korean preservice science teachers. Fifteen items from revised-New Ecological Paradigm based on value orientations were used as the research instrument. Two hundred seventy-three preservice science teachers participated in the study. Rasch analyses of dimensionality, item fit, and differential item functioning were used to explore the validity of the instrument. The independent-sample T-test and Pearson’s correlation test were utilized to compare data from the two countries. Preservice science teachers from the two different countries showed significant differences in only one of the three value orientations, which is egoistic value. Relationships among cultural, educational, and economic factors, as well as environmental values in these countries are discussed to fully explore the findings.

The Teen Screen for Dating Violence: An Item Response Theory Analysis.

There continues to be a lack of fundamental knowledge regarding assessment, conceptualization, and treatment of teen dating violence (TDV). This deficiency of knowledge becomes even greater when examining gender differences in violence experience, perpetration, and perception. This article details the item response theory (IRT) analysis of the Teen Screen for Dating Violence (TSDV) and includes an assessment of differential item functioning (DIF) reported by gender. The TSDV examines adolescents' perception, experience, perpetration, and exposure to violence, while also exploring support systems. The study participants included males and females between 13 and 21 years of age. Further refinement of the TSDV contributes to a more accurate and comprehensive conceptualization of TDV measurement. The results of this study support the use of the TSDV to assess for TDV in the adolescent population. The DIF analysis reveals that many of the items function differently for males and females, which provides evidence indicating that how TDV is experienced, perceived, and perpetrated differs across gender. The TSDV can assist clinicians in early TDV prevention, intervention, and education for males and females. It can also assist researchers in more accurately estimating perpetration, experience, and conceptualization of the three violence facets (emotional, physical, and sexual) in males and females. To further expand TDV knowledge, we offer recommendations for the use of the TSDV in various settings. The TSDV is a vital tool for clinicians, supervisors, and researchers to implement to mitigate the TDV epidemic and help bridge the gap in mental health services.