Measuring Unipolar Traits With Continuous Response Items: Some Methodological and Substantive Developments.

In recent years, some models for binary and graded format responses have been proposed to assess unipolar variables or "quasi-traits." These studies have mainly focused on clinical variables that have traditionally been treated as bipolar traits. In the present study, we have made a proposal for unipolar traits measured with continuous response items. The proposed log-logistic continuous unipolar model (LL-C) is remarkably simple and is more similar to the original binary formulation than the graded extensions, which is an advantage. Furthermore, considering that irrational, extreme, or polarizing beliefs could be another domain of unipolar variables, we have applied this proposal to an empirical example of superstitious beliefs. The results suggest that, in certain cases, the standard linear model can be a good approximation to the LL-C model in terms of parameter estimation and goodness of fit, but not trait estimates and their accuracy. The results also show the importance of considering the unipolar nature of this kind of trait when predicting criterion variables, since the validity results were clearly different.

Assessing the Relationship between Surgical Timing and Postoperative Seizure Outcomes in Cavernoma-Related Epilepsy: A Single-Institution Retrospective Analysis of 63 Patients with a Review of the Literature.

Background: Patients with supratentorial cavernous malformations (SCMs) commonly present with seizures. First-line treatments for cavernoma-related epilepsy (CRE) include conservative management (antiepileptic drugs (AEDs)) and surgery. We compared seizure outcomes of CRE patients after early (≤6 months) vs. delayed (>6 months) surgery. Methods: We compared outcomes of CRE patients with SCMs surgically treated at our large-volume cerebrovascular center (1 January 2010-31 July 2020). Patients with 1 sporadic SCM and ≥1-year follow-up were included. Primary outcomes were International League Against Epilepsy (ILAE) class 1 seizure freedom and AED independence. Results: Of 63 CRE patients (26 women, 37 men; mean ± SD age, 36.1 ± 14.6 years), 48 (76%) vs. 15 (24%) underwent early (mean ± SD, 2.1 ± 1.7 months) vs. delayed (mean ± SD, 6.2 ± 7.1 years) surgery. Most (32 (67%)) with early surgery presented after 1 seizure; all with delayed surgery had ≥2 seizures. Seven (47%) with delayed surgery had drug-resistant epilepsy. At follow-up (mean ± SD, 5.4 ± 3.3 years), CRE patients with early surgery were more likely to have ILAE class 1 seizure freedom and AED independence than those with delayed surgery (92% (44/48) vs. 53% (8/15), p = 0.002; and 65% (31/48) vs. 33% (5/15), p = 0.03, respectively). Conclusions: Early CRE surgery demonstrated better seizure outcomes than delayed surgery. Multicenter prospective studies are needed to validate these findings.

Determining Sample Size Requirements in EFA Solutions: A Simple Empirical Proposal.

In unrestricted or exploratory factor analysis (EFA), there is a wide range of recommendations about the size samples should be to attain correct and stable solutions. In general, however, these recommendations are either rules of thumb or based on simulation results. As it is hard to establish the extent to which a particular data set suits the conditions used in a simulation study, the advice produced by simulation studies is not direct enough to be of practical use. Instead of trying to provide general and complex recommendations, in this article, we propose to estimate the sample size that is needed to analyze a data set at hand. The estimation takes into account the specified EFA model. The proposal is based on an intensive simulation process in which the sample correlation matrix is used as a basis for generating data sets from a pseudo-population in which the parent correlation holds exactly, and the criterion for determining the size required is a threshold that quantifies the closeness between the pseudo-population and the sample reproduced correlation matrices. The simulation results suggest that the proposal works well and that the determinants identified agree with those in the literature.

Psychometric Properties and Measurement Invariance of the Herth Hope Index in Spanish Cancer Patients.

BACKGROUND: The aim of this study was to evaluate the psychometric properties, differential item functioning, factorial invariance, and convergent validity of the Spanish version of the Herth Hope Index (HHI) in patients with cancer. METHOD: Exploratory and confirmatory factor analyses were conducted to explore the scale, dimensionality, functioning of items, test for strong measurement invariance across sex, age, tumor site, and expected survival, and an extended structural equation model to assess external validity in a cross-sectional, multicenter, prospective study of 863 cancer patients from 15 Spanish hospitals. RESULTS: The results do not support the original 3-factor scale but instead suggest a one-factor structure, which explained 62% of the common variance. Scores from the unidimensional structure exhibited satisfactory reliability (ω = .88). A strong invariance solution demonstrated excellent fit across sex, age, tumor site, and survival. HHI exhibited substantial associations with resilience coping strategies and spiritual well-being. CONCLUSIONS: The findings of our study contribute to the diversity of earlier empirical findings regarding the construct of hope. Despite this, our results indicate that the Spanish version of the HHI is a short, easy-to-administer, valid, reliable tool for evaluating cancer patients' levels of hope.

Psychometric Properties and Measurement Invariance of the Herth Hope Index in Spanish Cancer Patients / Propiedades Psicométricas y Medida de Invarianza del Índice de Esperanza de Herth en Pacientes Oncológicos Españoles

Background: The aim of this study was to evaluate the psychometric properties, differential item functioning, factorial invariance, and convergent validity of the Spanish version of the Herth Hope Index (HHI) in patients with cancer. Method: Exploratory and confirmatory factor analyses were conducted to explore the scale, dimensionality, functioning of items, test for strong measurement invariance across sex, age, tumor site, and expected survival, and an extended structural equation model to assess external validity in a cross-sectional, multicenter, prospective study of 863 cancer patients from 15 Spanish hospitals. Results: The results do not support the original 3-factor scale but instead suggest a one-factor structure, which explained 62% of the common variance. Scores from the unidimensional structure exhibited satisfactory reliability (ω= .88). A strong invariance solution demonstrated excellent fit across sex, age, tumor site, and survival. HHI exhibited substantial associations with resilience coping strategies and spiritual well-being. Conclusions: The findings of our study contribute to the diversity of earlier empirical findings regarding the construct of hope. Despite this, our results indicate that the Spanish version of the HHI is a short, easy-to-administer, valid, reliable tool for evaluating cancer patients’ levels of hope.(AU)

Antecedentes: El objetivo de este estudio fue evaluar las propiedades psicométricas, el funcionamiento de los ítems, la invariancia factorial y la validez convergente de la versión española del Herth Hope Index (HHI) en pacientes con cáncer. Método: Estudio transversal, multicéntrico, prospectivo de 863 pacientes con cáncer de 15 hospitales españoles. Se realizaron análisis factoriales exploratorios y confirmatorios para explorar la dimensionalidad, el funcionamiento de los ítems, la invariancia de medición según el sexo, la edad, el sitio del tumor y la supervivencia esperada, y la validez externa. Resultados: Los resultados obtenidos no respaldan la escala original de 3 factores y en cambio sugieren una estructura de un factor, que explicó el 62% de la varianza común, con una confiabilidad satisfactoria (ω = .88). Una solución de invariancia fuerte demostró un excelente ajuste en función del sexo, la edad, el sitio del tumor y la supervivencia. HHI reveló asociaciones sustanciales con la resiliencia y el bienestar espiritual. Conclusiones: Nuestros resultados indican que la versión en español del HHI es una herramienta corta, fácil de administrar, válida y confiable para evaluar el nivel de esperanza de los pacientes con cáncer.(AU)

Relaxation differences using EIS through bronchoscopy of healthy and pathological lung tissue.

The use of electrical impedance spectroscopy for lung tissue differentiation is an opportunity for the improvement of clinical diagnosis. The aim of this work is to distinguish among different lung tissue states by evaluating the differences among impedance spectrum parameters between two separate frequencies (15 kHz and 307 kHz) in the beta dispersion region. In previous studies we have used single frequency measurements for tissue differentiation. Differences (P < 0.05) are found between those tissues that undergo an increase in tissue density (neoplasm and fibrosis) and those tissues that lead to tissue destruction (emphysema). Electrical impedance spectroscopy shows its utility for lung tissue differentiation for diagnosis improvement among pathologies with different tissue structure. Further studies are necessary for the differentiation among those tissue states that are more similar to each other.Clinical Relevance- Expand the diagnostic tools currently available in bronchoscopy by using minimally-invasive bioimpedance measurements to differentiate between lung patterns.

Is it quality, is it redundancy, or is model inadequacy? Some strategies for judging the ap-propriateness of high-discrimination items / ¿Es calidad, redundancia o inadecuación del modelo? Algunas estrategias para determinar la idoneidad de los ítems altamente discriminativos

Cuando se desarrollan nuevos cuestionarios, tradicionalmente se asume que los ítems deben ser lo más discriminativos posible, como si esto fuera siempre indicativo de su calidad. Pero en algunos casos estas discriminaciones elevadas pueden estar ocultando algunos problemas como redundancias, residuales compartidos, distribuciones sesgadas o limitaciones del modelo que pueden contribuir a inflar las estimaciones de la discriminación. Por lo tanto, la inspección de estos índices puede llevar a decisiones erróneas sobre qué ítems mantener o eliminar. Para ilustrar este problema, se describen dos escenarios diferentes con datos reales. El primero se centra en un cuestionario que contiene un ítem aparentemente muy discriminante, pero redundante. El segundo se centra en un cuestionario clínico administrado a una muestra comunitaria, lo que da lugar a distribuciones de respuesta de los ítems muy sesgadas y a índices de discriminación inflados, a pesar de que los ítems no discriminan bien entre la mayoría de los sujetos. Proponemos algunas estrategias y comprobaciones para identificar estas situaciones, para facilitar la identificación y eliminación de los ítems inapropiados. Por lo tanto, este artículo pretende promover una actitud crítica, que puede implicar ir en contra de los principios rutinarios establecidos cuando no son apropiados.(AU)

When developing new questionnaires, it is traditionally assumed that the items should be as discriminative as possible, as if this was always indicative of their quality. However, in some cases these high discrimina-tions may be masking some problems such as redundancies, shared residu-als, biased distributions, or model limitations which may contribute to in-flate the discrimination estimates. Therefore, the inspection of these indi-ces may lead to erroneous decisions about which items to keep or elimi-nate. Toillustrate this problem, two different scenarios with real data are described. The first focuses on a questionnaire that contains an item ap-parently highly discriminant, but redundant. The second focuses on a clini-cal questionnaire administered to a community sample, which gives place to highly right-skewed item response distributions and inflated discrimi-nant indices, despite the items do not discriminate well among the majority of participants. We propose some strategies and checks to identify these situations, so that the items that are inappropriate may be identified and removed. Therefore, this article seeks to promote a critical attitude, which may involve going against routine stablished principles when they are not appropriate.(AU)

Gulliksen's pool: A quick tool for preliminary detection of problematic items in item factor analysis.

Exploratory factor analysis is widely used for item analysis in the earlier stages of scale development, usually with large pools of items. In this scenario, the presence of inappropriate or ineffective items can hamper the process of analysis, making it very difficult to correctly assess dimensionality and structure. To minimize, this (quite frequent) problem, we propose and implement a simple procedure designed to flag potentially problematic items before we specify any particular factorial solution. The procedure defines regions of item appropriateness and efficiency based on the combined impact of two prior item features: extremeness and consistency. The general proposal is related to the most widely used frameworks for item analysis. The limits of the appropriateness regions are obtained by extensive simulation in conditions that mimic those found in applications. An Item Response Theory index of prior item efficiency is then defined, and a combined approach for selecting the most effective and problem-free item sub-set is proposed. The proposal is useful to normal-range measures, such as questionnaire surveys that elicit reports about non-extreme attitudes, facts, beliefs or states, or personality questionnaires that measure normal-range constructs. The procedure is implemented in a freeware software.

Differentiation using minimally-invasive bioimpedance measurements of healthy and pathological lung tissue through bronchoscopy.

Purpose: To use minimally-invasive transcatheter electrical impedance spectroscopy measurements for tissue differentiation among healthy lung tissue and pathologic lung tissue from patients with different respiratory diseases (neoplasm, fibrosis, pneumonia and emphysema) to complement the diagnosis at real time during bronchoscopic procedures. Methods: Multi-frequency bioimpedance measurements were performed in 102 patients. The two most discriminative frequencies for impedance modulus (|Z|), phase angle (PA), resistance (R) and reactance (Xc) were selected based on the maximum mean pair-wise Euclidean distances between paired groups. One-way ANOVA for parametric variables and Kruskal-Wallis for non-parametric data tests have been performed with post-hoc tests. Discriminant analysis has also been performed to find a linear combination of features to separate among tissue groups. Results: We found statistically significant differences for all the parameters between: neoplasm and pneumonia (p < 0.05); neoplasm and healthy lung tissue (p < 0.001); neoplasm and emphysema (p < 0.001); fibrosis and healthy lung tissue (p ≤ 0.001) and pneumonia and healthy lung tissue (p < 0.01). For fibrosis and emphysema (p < 0.05) only in |Z|, R and Xc; and between pneumonia and emphysema (p < 0.05) only in |Z| and R. No statistically significant differences (p > 0.05) are found between neoplasm and fibrosis; fibrosis and pneumonia; and between healthy lung tissue and emphysema. Conclusion: The application of minimally-invasive electrical impedance spectroscopy measurements in lung tissue have proven to be useful for tissue differentiation between those pathologies that leads increased tissue and inflammatory cells and those ones that contain more air and destruction of alveolar septa, which could help clinicians to improve diagnosis.

Compliance with COVID-19 Preventive Measures: The Role of Intelligence, the Dark Triad and Dysfunctional Impulsivity.

BACKGROUND: Although measures to prevent COVID-19 infection have been greatly relaxed in many countries, they are still quite stringent in others. However, not all citizens comply with them to the same extent. Many studies show the importance of personality traits in predicting compliance with these measures, but it is not so clear what the role of intelligence is. Therefore, we aimed to assess whether intelligence is related to compliance with these measures, and what its predictive role is when considered together with the dark triad and dysfunctional impulsivity. METHOD: A total of 786 participants answered four questionnaires. We performed correlations, multiple regression analysis, and structural equation analysis. RESULTS: Multiple regression analysis showed that psychopathy and dysfunctional impulsivity were the variables that contributed most to compliance, while intelligence contributed very little. The results of the structural equation modelling suggested that intelligence had only an indirect relationship with compliance, through its relationship with the negative personality traits dysfunctional impulsivity and the dark triad. CONCLUSIONS: Intelligence seems to modulate the relationship between negative personality traits and compliance. Therefore, more intelligent people with negative personality traits would not tend to have such low levels of compliance.

Are older teens more frustrated than younger teens by the covid-19 restrictions? The role of psychological maturity, personality traits, depression and life satisfaction.

Many studies have shown the negative impact of lockdowns on adolescents, but there is less evidence on how they are affected by other stages of the COVID-19 pandemic, and, especially, whether there are any differences between early and late adolescence. The current study focuses on the frustration felt by adolescents because of the severe COVID-19 restrictions in a non-lockdown situation. We aimed to (a) assess the role of maturity and two personality traits (emotional stability and extraversion) in predicting their frustration, and (b) compare the levels of frustration, depressive symptoms, and life satisfaction in older and younger adolescents. The sample of older adolescents was also compared with a paired sample of the same age collected in 2018, before the pandemic. The results suggest that maturity, extraversion and emotional stability are predictors of frustration in both older and younger adolescents, although older adolescents reported higher levels of frustration and depressive symptoms, and lower levels of life satisfaction. Older adolescents also reported higher levels of depressive symptoms than adolescents of the same age before the pandemic. These results show the negative impact of the pandemic, especially on older adolescents, and the important role of maturity and some personality traits in predicting their frustration.

Which profile of people tends to ignore preventive measures against COVID-19? The role of intelligence and the big five personality traits.

Although a considerable amount of research has been done on the role of personality traits in the prediction of compliance with COVID-19 preventive measures, the possible role of intelligence has been studied far less. For this reason, the main goal of the current study was to determine what the predictive role of intelligence is when considered together with the Big Five personality traits. A total of 404 participants answered three instruments: the Overall Personality Assessment Scale (OPERAS), which assesses personality traits, the COmpliance with pandemic COmmands Scale (COCOS), which assesses compliance, and the test of intelligence International Cognitive Ability Resource (ICAR Sample Test). The results show that all variables are correlated with compliance, although the weight of emotional stability on compliance was not significant. The only variable negatively related to compliance was extraversion. The results of the structural equation modelling suggest that intelligence has a direct relationship with compliance, and an indirect relationship through openness to experience. According to the results, intelligence is an important variable that should be considered in the prediction of compliance with these preventive measures.

Compliance with COVID-19 Preventive Measures: The Role of Intelligence, the Dark Triad and Dysfunctional Impulsivity / Cumplimiento de Medidas Preventivas Asociadas a la COVID-19: El Rol de la Inteligencia, la Triada Oscura y la Impulsividad Disfuncional

Background: Although measures to prevent COVID-19 infection have been greatly relaxed in many countries, theyare still quite stringent in others. However, not all citizens comply with them to the same extent. Many studies showthe importance of personality traits in predicting compliance with these measures, but it is not so clear what the roleof intelligence is. Therefore, we aimed to assess whether intelligence is related to compliance with these measures,and what its predictive role is when considered together with the dark triad and dysfunctional impulsivity. Method:A total of 786 participants answered four questionnaires. We performed correlations, multiple regression analysis,and structural equation analysis. Results: Multiple regression analysis showed that psychopathy and dysfunctionalimpulsivity were the variables that contributed most to compliance, while intelligence contributed very little. The resultsof the structural equation modelling suggested that intelligence had only an indirect relationship with compliance,through its relationship with the negative personality traits dysfunctional impulsivity and the dark triad. Conclusions:Intelligence seems to modulate the relationship between negative personality traits and compliance. Therefore, moreintelligent people with negative personality traits would not tend to have such low levels of compliance.(AU)

Antecedentes: Las medidas para controlar la COVID-19 se han relajado en muchos países, pero algunos todavíamantienen medidas estrictas, aunque hay ciudadanos que las incumplen. Muchos estudios muestran la relevancia de losrasgos de personalidad en la predicción del cumplimiento, pero no está tan claro cuál es el rol de la inteligencia. Por eso,los objetivos eran evaluar si la inteligencia está relacionada con el cumplimiento, y cuál es su papel predictivo cuandose considera junto con la tríada oscura y la impulsividad disfuncional. Método: 786 participantes respondieron cuatrocuestionarios. Se realizaron correlaciones, regresión múltiple y análisis de ecuaciones estructurales. Resultados: Elanálisis de regresión mostró que la psicopatía y la impulsividad eran las variables con una mayor contribución, mientrasque la inteligencia contribuía de forma pobre. Los resultados del modelo de ecuaciones estructurales sugieren que lainteligencia tiene una relación indirecta con el cumplimiento, a través de su relación con la impulsividad disfuncionaly la tríada oscura. Conclusiones: La inteligencia parece modular la relación entre los rasgos negativos de personalidady el cumplimiento de las medidas preventivas, por lo que las personas más inteligentes, pero con rasgos negativos depersonalidad, no tenderían a tener niveles tan bajos de cumplimiento.(AU)

Development of a Revised Version of the Statistical Anxiety Scale.

BACKGROUND: Statistics anxiety is a common problem in students taking statistics courses in the social sciences. It is most widely measured by the statistical anxiety scale. The various adaptations of this instrument have shown certain problems in the replication of its factorial structure and do not have a system to control possible response bias effects. The objective of our study was to propose a short test to measure statistical anxiety that also includes a scale to control social desirability bias. METHOD: We developed a revised version of the statistical anxiety scale using procedures for controlling response biases and examined its factorial structure using exploratory and confirmatory analysis in a sample of 531 students. RESULTS: The revised version showed a clear four-factor structure in exploratory and confirmatory factor analyses with the expected three content factors plus one social desirability factor. The scales showed no acquiescence effects and moderate social desirability effects, and had a clear relationship with academic success. CONCLUSIONS: The revised version of the statistical anxiety scale improves on the psychometric properties of the original version and may overcome the problems detected in some adaptations of the previous version.

Measurement properties of the Spanish version of the brief resilient coping scale (BRCS) in cancer patients

Background/Objective: Resilience is the capacity to adaptively confront stress. The aim of this study was to evaluate the psychometric properties, convergent validity, and factorial invariance of the Spanish version of the Brief Resilient Coping Scale (BRCS).Method: Exploratory and confirmatory factor analyses based on a cross-validation were conducted to explore the scale's dimensionality and test for strong (scalar) measurement invariance across gender, age, tumor site, and survival, by fitting multiple-group confirmatory solutions. An extended structural equation model was used to assess external validity. Prospective, multicenter cohort study of 636 patients who completed the BRCS, Satisfaction with Life Scale (SWLS), and Spiritual well‐being (FACIT-sp) scales.Results: The data supported a unidimensional structure. The BRCS is a very short, narrow bandwidth measure, with items demonstrating high discriminating power. A strong invariance solution demonstrated excellent fit across gender, age, tumor site, and survival. Scores derived from the unidimensional structure exhibited satisfactory degrees of reliability (ω = .86) and determinacy (FDI = .94). BRCS revealed substantial associations with satisfaction with life and spirituality well-being (all p < .001), factors widely related to resilience, particularly in cancer patients.Conclusions: The Spanish version of the BRCS is a reliable, valid resilience measure in advanced cancer. (AU)

Measurement properties of the Spanish version of the brief resilient coping scale (BRCS) in cancer patients.

Background/Objective: Resilience is the capacity to adaptively confront stress. The aim of this study was to evaluate the psychometric properties, convergent validity, and factorial invariance of the Spanish version of the Brief Resilient Coping Scale (BRCS). Method: Exploratory and confirmatory factor analyses based on a cross-validation were conducted to explore the scale's dimensionality and test for strong (scalar) measurement invariance across gender, age, tumor site, and survival, by fitting multiple-group confirmatory solutions. An extended structural equation model was used to assess external validity. Prospective, multicenter cohort study of 636 patients who completed the BRCS, Satisfaction with Life Scale (SWLS), and Spiritual well-being (FACIT-sp) scales. Results: The data supported a unidimensional structure. The BRCS is a very short, narrow bandwidth measure, with items demonstrating high discriminating power. A strong invariance solution demonstrated excellent fit across gender, age, tumor site, and survival. Scores derived from the unidimensional structure exhibited satisfactory degrees of reliability (ω = .86) and determinacy (FDI = .94). BRCS revealed substantial associations with satisfaction with life and spirituality well-being (all p < .001), factors widely related to resilience, particularly in cancer patients. Conclusions: The Spanish version of the BRCS is a reliable, valid resilience measure in advanced cancer.

The Role of Psychological Maturity and the Big Five Personality Traits in the Victimization Through Indirect Aggression.

BACKGROUND: Peer victimization is a problem that affects adolescents worldwide. Since so few studies have been made on the relationship between maturity and indirect peer victimization, the main objective of this study was to determine if maturity provides incremental validity beyond the personality traits when predicting indirect victimization. Another objective was to test a model of how all these variables are related to depressive symptomatology and life satisfaction. METHOD: 548 high school students completed five questionnaires. We performed correlations, multiple regression analysis and structural equation analysis. RESULTS: The hierarchical regression analyses show that maturity has incremental validity in predicting indirect peer victimization. Two personality traits (emotional stability and agreeableness) and two maturity factors (identity and self-reliance) were major predictors of indirect peer victimization. The hierarchical regression analyses also show that major predictors were the same for girls and boys. The Structural Equation Model tested had a good fit, which suggests that indirect victimization increases depressive symptomatology and decreases life satisfaction. CONCLUSIONS: The results suggest that both personality traits and psychological maturity have to be taken into account when predicting indirect peer victimization. The study also shows the emotional suffering related to this victimization.

Translation, adaptation and psychometric properties of the Arabic version of the numerical rating scale when used with children and adolescents.

OBJECTIVE: The 0-10 Numerical Rating Scale (NRS-11) is widely used with Arabic-speaking pediatric populations. However, there is no data about its validity or reliability. Thus, the aims of this research were to translate the NRS-11 into Arabic and study its dimensionality and construct (convergent and discriminant) validity, and reliability. METHODS: A group of 190 Lebanese students between 8 and 18 years old participated. Participants were interviewed online and asked to imagine themselves in a hypothetical painful situation and rate the expected pain intensity using the NRS-11-Arabic and an Arabic version of the Visual Analogue Scale (VAS-Arabic). They were also requested to respond to the pediatric Arabic version of the Pain Catastrophizing Scale (PCS-Arabic). Data collection lasted for a month. RESULTS: Data showed that the NRS-11-Arabic and the VAS-Arabic scores measure the same common construct. In addition, they showed strong statistically significant correlations between NRS-11 and VAS (ranging from 0.83 for the whole sample and 0.83 and 0.84 for the 8-12-year-olds and the 13-18-year-olds, which support its construct validity). These correlations were higher than those between the NRS-11-Arabic and the PCS-Arabic, which support the discriminant validity of NRS-11-Arabic scores. Test-retest reliability was 0.86 for the whole sample, and 0.89 and 0.82 for the 8-12-year-olds and the 13-18-year-olds, respectively, which shows the reliability of the NRS-11-Arabic scores. CONCLUSIONS: The data provide preliminary evidence of the unidimensionality, validity and reliability of the NRS-11-Arabic scores, thus supporting its use in clinical and research activities involving Arabic-speaking pediatric samples.