Adapting cognitive diagnosis computerized adaptive testing item selection rules to traditional item response theory

Currently, there are two predominant approaches in adaptive testing. One, referred to as cognitive diagnosis computerized adaptive testing (CD-CAT), is based on cognitive diagnosis models, and the other, the traditional CAT, is based on item response theory. The present study evaluates the performance of two item selection rules (ISRs) originally developed in the CD-CAT framework, the double Kullback-Leibler information (DKL) and the generalized deterministic inputs, noisy and gate model discrimination index (GDI), in the context of traditional CAT. The accuracy and test security associated with these two ISRs are compared to those of the point Fisher information and weighted KL using a simulation study. The impact of the trait level estimation method is also investigated. The results show that the new ISRs, particularly DKL, could be used to improve the accuracy of CAT. Better accuracy for DKL is achieved at the expense of higher item overlap rate. Differences among the item selection rules become smaller as the test gets longer. The two CD-CAT ISRs select different types of items: items with the highest possible a parameter with DKL, and items with the lowest possible c parameter with GDI. Regarding the trait level estimator, expected a posteriori method is generally better in the first stages of the CAT, and converges with the maximum likelihood method when a medium to large number of items are involved. The use of DKL can be recommended in low-stakes settings where test security is less of a concern

Healthy orthorexia vs. orthorexia nervosa: Italian validation of the Teruel Orthorexia Scale (TOS)

Purpose: Orthorexia nervosa (OrNe) is a potentially pathological condition characterized by a fixation on healthy diet. An increasing number of studies have been conducted on this mental preoccupation, but the validity and reliability of some of the psychometric instruments employed in its assessment are still under debate. Among these measures, the Teruel Orthorexia Scale (TOS) seems to be promising, given that it allows to differentiate between OrNe and other non-problematic forms of interest with healthy eating, named as healthy orthorexia (HeOr). The aim of this study was to examine the psychometric properties of an Italian version of the TOS, by testing its factorial structure, internal consistency, test–retest reliability, and validity. Method: Through an online survey, we recruited 782 participants from different regions of Italy, asking them to complete the following self-report instruments: TOS, EHQ, EDI-3, OCI-R, and BSI-18. From the initial sample, 144 participants agreed to complete a second TOS administration 2 weeks later. Results: Data confirmed the validity of the 2-correlated factors structure of the TOS. The questionnaire also showed good reliability, both in terms of internal consistency and temporal stability. With regard to the TOS validity, results showed that OrNe was significantly and positively associated with measures of psychopathology and psychological distress, while HeOr showed no correlations or negative associations with the above-mentioned measures. Conclusion: Based on these results, the TOS can be considered a promising measure for the assessment of both pathological and non-problematic forms of orthorexic eating behavior also in Italian population. Level of evidence: Level V, descriptive cross-sectional study

Healthy Orthorexia vs. Orthorexia Nervosa: Italian validation of the Teruel Orthorexia Scale (TOS).

Purpose Orthorexia nervosa (OrNe) is a potentially pathological condition characterized by a fixation on healthy diet. An increasing number of studies have been conducted on this mental preoccupation, but the validity and reliability of some of the psychometric instruments employed in its assessment are still under debate. Among these measures, the Teruel Orthorexia Scale (TOS) seems to be promising, given that it allows to differentiate between OrNe and other non-problematic forms of interest with healthy eating, named as healthy orthorexia (HeOr). The aim of this study was to examine the psychometric properties of an Italian version of the TOS, by testing its factorial structure, internal consistency, test–retest reliability, and validity. Method Through an online survey, we recruited 782 participants from different regions of Italy, asking them to complete the following self-report instruments: TOS, EHQ, EDI-3, OCI-R, and BSI-18. From the initial sample, 144 participants agreed to complete a second TOS administration 2 weeks later. Results Data confirmed the validity of the 2-correlated factors structure of the TOS. The questionnaire also showed good reliability, both in terms of internal consistency and temporal stability. With regard to the TOS validity, results showed that OrNe was significantly and positively associated with measures of psychopathology and psychological distress, while HeOr showed no correlations or negative associations with the above-mentioned measures. Conclusion Based on these results, the TOS can be considered a promising measure for the assessment of both pathological and non-problematic forms of orthorexic eating behavior also in Italian population. Level of evidence Level V, descriptive cross-sectional study

Occipitofrontal circumference in newborns of betamethasone treated mothers

Peer Reviewe

A school-based program implemented by community providers previously trained for the prevention of eating and weight-related problems in secondary-school adolescents : the MABIC study protocol

Background: The prevention of eating disorders and disordered eating are increasingly recognized as public health priorities. Challenges in this field included moving from efficacy to effectiveness and developing an integrated approach to the prevention of a broad spectrum of eating and weight-related problems. A previous efficacy trial indicated that a universal disordered eating prevention program, based on the social cognitive model, media literacy educational approach and cognitive dissonance theory, reduced risk factors for disordered eating, but it is unclear whether this program has effects under more real-world conditions. The main aim of this effectiveness trial protocol is to test whether this program has effects when incorporating an integrated approach to prevention and when previously-trained community providers implement the intervention. Methods/design: The research design involved a multi-center non-randomized controlled trial with baseline, post and 1-year follow-up measures. Six schools from the city of Sabadell (close to Barcelona) participated in the intervention group, and eleven schools from four towns neighboring Sabadell participated in the control group. A total of 174 girls and 180 boys in the intervention group, and 484 girls and 490 boys in the control group were registered in class lists prior to baseline. A total of 18 community providers, secondary-school class tutors, nurses from the Catalan Government's Health and School Program, and health promotion technicians from Sabadell City Council were trained and delivered the program. Shared risk factors of eating and weight-related problems were assessed as main measures. Discussion: It will be vital for progress in disordered eating prevention to conduct effectiveness trials, which test whether interventions are effective when delivered by community providers under ecologically valid conditions, as opposed to tightly controlled research trials. The MABIC project will provide new contributions in this transition from efficacy to effectiveness and new data about progress in the integrated approach to prevention. Pending the results, the effectiveness trial meets the effectiveness standards set down by the Society for Prevention Research. This study will provide new evidence to improve and enhance disordered eating prevention programs

Extracting the Evaluations of Stereotypes: Bi-factor Model of the Stereotype Content Structure

Stereotype dimensions-competence, morality and sociability-are fundamental to studying the perception of other groups. These dimensions have shown moderate/high positive correlations with each other that do not reflect the theoretical expectations. The explanation for this (e.g., halo effect) undervalues the utility of the shared variance identified. In contrast, in this work we propose that this common variance could represent the global evaluation of the perceived group. Bi-factor models are proposed to improve the internal structure and to take advantage of the information representing the shared variance among dimensions. Bi-factor models were compared with first order models and other alternative models in three large samples (300-309 participants). The relationships among the global and specific bi-factor dimensions with a global evaluation dimension (measured through a semantic differential) were estimated. The results support the use of bi-factor models rather than first order models (and other alternative models). Bi-factor models also show a greater utility to directly and more easily explore the stereotype content including its evaluative content

Iteration of Partially Specified Target Matrices: Application to the Bi-Factor Case

<p>The current study proposes a new bi-factor rotation method, Schmid-Leiman with iterative target rotation (SLi), based on the iteration of partially specified target matrices and an initial target constructed from a Schmid-Leiman (SL) orthogonalization. SLi was expected to ameliorate some of the limitations of the previously presented SL bi-factor rotations, SL and SL with target rotation (SLt), when the factor structure either includes cross-loadings, near-zero loadings, or both. A Monte Carlo simulation was carried out to test the performance of SLi, SL, SLt, and the two analytic bi-factor rotations, bi-quartimin and bi-geomin. The results revealed that SLi accurately recovered the bi-factor structures across the majority of the conditions, and generally outperformed the other rotation methods. SLi provided the biggest improvements over SL and SLt when the bi-factor structures contained cross-loadings and pure indicators of the general factor. Additionally, SLi was superior to bi-quartimin and bi-geomin, which performed inconsistently across the types of factor structures evaluated. No method produced a good recovery of the bi-factor structures when small samples (N = 200) were combined with low factor loadings (0.30–0.50) in the specific factors. Thus, it is recommended that larger samples of at least 500 observations be obtained.</p