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Gender differences in item nonresponse are well-documented in high-stakes achievement tests, where female students are shown to omit more items than male students. These gender differences in item nonresponse are often linked to differential risk-taking strategies, with females being risk-averse and unwilling to guess on an item, even if it could gain them credits. In low-stakes settings, similar trends should not apply, as the students carry no consequence for their performance. Instead, test-taking motivation is argued to be the pivoting factor, with female students seen as more motivated and omitting fewer items than male students. In contrast to the high- and low-stakes achievement tests, less is known about gender differences in item nonresponse in student background questionnaires. Using cross-classified mixed effects models, we examined gender differences in item nonresponse on the Programme for International Student Assessment (PISA) 2018 student questionnaire across 80 countries and 71 scales. On average, the odds of male students omitting a questionnaire item were double the odds of female students, consistent with the expected trend in the low-stakes setting. However, we show that gender differences in item nonresponse are not merely a function of the stakes involved for individual students but a more complex phenomenon that is context-dependent and not necessarily stable across countries, scales' formats, and contents. We argue that examining differences in item nonresponse patterns could serve as a source of additional information about the students' test-taking behaviour and the quality of the questionnaire.

We investigated two research questions: which students are more likely to respond inconsistently to mixed-worded questionnaire scales, and which country samples have larger shares of inconsistent respondents? We defined an inconsistent response as strongly agreeing or disagreeing with both positively and negatively worded items of the same scale. Since we assumed that inconsistent responding occurs due to a lack of carefulness, reading, or cognitive skills, we expected to find that inconsistent responding was associated with lower achievement, younger age, being a nonnative speaker, and being a boy. We used data from all 38 countries that participated in the fourth- and eighth-grade assessments of TIMSS (Trends in International Mathematics and Science Study) 2019. Using the mean absolute difference method, we identified shares of 1-21% inconsistent respondents across samples. The results generally supported our hypotheses, especially the hypothesis that inconsistent responding is more common among students and countries with lower mathematics achievement levels.

This study examined the impact of two questionnaire characteristics, scale position and questionnaire length, on the prevalence of random responders in the TIMSS 2015 eighth-grade student questionnaire. While there was no support for an absolute effect of questionnaire length, we did find a positive effect for scale position, with an increase of 5% in random responding over the course of the questionnaire (in both the shorter and the longer version). However, scale character turned out to be an unexpected but more important determinant. Scales about students' confidence in mathematics or science showed an increase of 9% in random responding, which is double the impact of scale position. Potential mechanisms underlying the confidence case and general implications of the results for questionnaire design are discussed.

Questionnaires in educational research assessing students' attitudes and beliefs are low-stakes for the students. As a consequence, students might not always consistently respond to a questionnaire scale but instead provide more random response patterns with no clear link to items' contents. We study inter-individual differences in students' intra-individual random responding profile across 19 questionnaire scales in the TIMSS 2015 eighth-grade student questionnaire in seven countries. A mixture IRT approach was used to assess students' random responder status on a questionnaire scale. A follow-up latent class analysis across the questionnaire revealed four random responding profiles that generalized across countries: A majority of consistent nonrandom responders, intermittent moderate random responders, frequent random responders, and students that were exclusively triggered to respond randomly on the confidence scales in the questionnaire. We discuss the implications of our findings in light of general data-quality concerns and the potential ineffectiveness of early-warning monitoring systems in computer-based surveys.

Despite the sensitivity of fit indices to various model and data characteristics in structural equation modeling, these fit indices are used in a rigid binary fashion as a mere rule of thumb threshold value in a search for model adequacy. Here, we address the behavior and interpretation of the popular Comparative Fit Index (CFI) by stressing that its metric for model assessment is the amount of misspecification in a baseline model and by further decomposition into its fundamental components: sample size, number of variables and the degree of multivariate dependence in the data. Simulation results show how these components influence the performance of CFI and its rule of thumb in practice. We discuss the usefulness of additional qualifications when applying the CFI rule of thumb and potential adjustments to its threshold value as a function of data characteristics. In conclusion, we at a minimum recommend a dual reporting strategy to provide the necessary context and base for meaningful interpretation and even more optimal, a move to using CFI as a real incremental fit index intended to evaluate the relative effect size of cumulative theoretically motivated model restrictions in terms of % reduction in misspecification as measured by the baseline model.

IntroductionUNICEF’s Education For All steers for equal opportunities for all students and diversity in the student population. In Ethiopia, affirmative action is the policy tool addressing equity in enrolment and admission to higher education, targeting underrepresented groups such as females and students from emerging regions.MethodsIn a cross-sectional study across two-levels of education, regional differences in enrolment and admission eligibility were explored for two census student cohorts at high school (n = 858,557 and n = 785,053) and at the university preparatory program (n = 199,899 and n = 211,706). These population-level data stem from governmental registers from the mandatory national exams. Enrolment and admission eligibility statistics were computed with special attention to gender imparity. The impact of affirmative action was studied by comparison to the corresponding projected statistics computed as if affirmative action did not apply.ResultsIn most regions, clearly more male than female students were enrolled across the different educational levels. Affirmative action benefitted a significant percentage of female and emerging-region students. The gender parity in eligibility rates for admission to preparatory program for most regions was restored, but not for admission to university.DiscussionBeing implemented as policy directive for nearly three decades, affirmative action at most maintained gender imparity levels in enrolment inherited from earlier educational stages but failed in redressing inequity across gender and regions. Policy implications of the results and recommendations are discussed in light of regional differences and the currently implemented type of affirmative action.

Background: COVID-19 patients frequently experience pulmonary embolism (PE), but its long-term consequences remain uncertain. Objectives: To assess the impact of PE in COVID-19 patients on health outcomes at 3 months after hospitalization. Methods: In this multicenter cross-sectional study, we aggregated data from existing databases to evaluate the impact of PE on health outcomes at 3 months after hospitalization. We assessed 1) questionnaires on health-related quality of life (5-level EuroQol 5-dimensional questionnaire [EQ-5D-5L] questionnaire), anxiety, depression, cognitive failure, and posttraumatic stress disorder; 2) pulmonary function tests (diffusing capacity of the lungs for carbon monoxide [DLCO] and spirometry); and 3) radiological abnormalities. We developed 3 models to assess the association between PE and the EQ-5D-5L index and the percentage of predicted DLCO (DLCO%): a crude model (model 1), adjusted for age, sex, and presence of comorbidities (model 2), and model 2 additionally adjusted for intensive care unit admission (model 3). Results: We included 465 patients who had been hospitalized for COVID-19, of whom 102 (21.9%) had developed a PE during admission. Patients with PE had poorer EQ-5D-5L index values, more impairment in pulmonary functions, and more frequent radiological abnormalities than patients without PE. Symptoms of anxiety, depression, cognitive failure, and posttraumatic stress disorder did not differ between the 2 groups. In model 2, PE was associated with lower EQ-5D-5L index and lower DLCO%. After additionally adjusting for intensive care unit admission, the association between PE and lower EQ-5D-5L index (mean difference = −0.069, [95% CI, −0.12 to −0.017]) remained but not between PE and DLCO%. Conclusion: Our findings suggest that PE in COVID-19 patients is associated with reduced health-related quality of life at 3 months after hospitalization. While PE may be a marker of COVID-19 severity, its presence during hospitalization could indicate potential long-term health issues, which may be considered during follow-up care.

Embedded Operating Systems (OSs) are often developed in the C programming language. Developers justify this choice by the performance that can be achieved, the low memory footprint, and the ease of mapping hardware to software, as well as the strong adoption by industry of this programming language. The downside is that C is prone to security vulnerabilities unknowingly introduced by the software developer. Examples of such vulnerabilities are use-after-free, and buffer overflows. Like C, Rust is a compiled programming language that guarantees memory safety at compile time by adhering to a set of rules. There already exist a few OSs and frameworks that are entirely written in Rust, targeting sensor nodes. In this work, we give an overview of these OSs and frameworks and compare them on the basis of the features they provide, such as application isolation, scheduling, inter-process communication, and networking. Furthermore, we compare the OSs on the basis of the performance they provide, such as cycles and memory usage.

A general validity and survey quality concern with student questionnaires under low-stakes assessment conditions is that some responders will not genuinely engage with the questionnaire, often with more random response patterns as a result. Using a mixture IRT approach and a meta-analytic lens across 22 educational systems participating in TIMSS 2015, we investigated whether the prevalence of random responders on six scales regarding students' engagement and attitudes toward mathematics and sciences was a function of grade, gender, socio-economic status, spoken language at home, or migration background. Among these common policy-relevant covariates in educational research, we found support for small group differences in prevalence of random responders (OR [greater than or equal to] 1.22] ) (average prevalence of 7%). In general, being a student in grade 8 (vs. grade 4), being male, reporting to have fewer books, or speaking a language different from the test language at home were all risk factors characterizing random responders. The expected generalization and implications of these findings are discussed based on the observed heterogeneity across educational systems and consistency across questionnaire scales.

Abstract A general validity and survey quality concern with student questionnaires under low-stakes assessment conditions is that some responders will not genuinely engage with the questionnaire, often with more random response patterns as a result. Using a mixture IRT approach and a meta-analytic lens across 22 educational systems participating in TIMSS 2015, we investigated whether the prevalence of random responders on six scales regarding students’ engagement and attitudes toward mathematics and sciences was a function of grade, gender, socio-economic status, spoken language at home, or migration background. Among these common policy-relevant covariates in educational research, we found support for small group differences in prevalence of random responders ( $${\text {OR}}\ge 1.22$$ OR ≥ 1.22 ) (average prevalence of 7%). In general, being a student in grade 8 (vs. grade 4), being male, reporting to have fewer books, or speaking a language different from the test language at home were all risk factors characterizing random responders. The expected generalization and implications of these findings are discussed based on the observed heterogeneity across educational systems and consistency across questionnaire scales.

Abstract Background Pregnancy and the transition to parenthood are accompanied by multiple changes and stress exposure. Resilience has the potential to counteract the negative impact of stress and can be a protective factor against mental health problems. To date, the use of a theoretical framework in the development or application of resilience interventions during pregnancy up to one year postpartum is missing. The aim of this study is to develop an intervention to enhance resilience for pregnant women up to one year postpartum. Methods A systematic and theory-based approach informed by the Behaviour Change Wheel framework and the theoretical model of perinatal resilience was applied. The development took place in three phases and during the process, the target group, researchers and clinicians were involved. Results A combination of resilience-enhancing exercises, group sessions and an online support platform, including follow-up at six and twelve months after delivery, was designed to enhance resilience during pregnancy and up to one year postpartum. This intervention incorporates 5 intervention functions delivered by 18 behaviour change techniques. Conclusions This study responds to the need for theory-based intervention programs aiming to enhance resilience to improve the psychological health of pregnant women. We developed a multicomponent resilience-enhancing intervention for pregnant women up to one year postpartum.

Environmental monitoring is essential for safeguarding the health of our planet and protecting human health and well-being. Without trust, the effectiveness of environmental monitoring and the ability to address environmental challenges are significantly compromised. In this paper, we present a sensor platform capable of performing authenticated and trustworthy measurements, together with a lightweight security protocol for sending the data from the sensor to a central server anonymously. Besides presenting a new and very efficient symmetric-key-based protocol, we also demonstrate on real hardware how existing embedded security modules can be utilized for this purpose. We provide an in-depth evaluation of the performance and a detailed security analysis.

Typically, nano-emulsions are prepared in batch high-speed homogenization or ultrasound processes and polymerized afterwards in batch reactors. However, fully continuous processes have the potential to decrease production costs and energy consumption compared to batch processes. This research thus focuses on implementing ultrasound into a fully continuous emulsification and nano-emulsion polymerization process to obtain latex nano-particles from butylmethacrylate and ethylene glycol dimethacrylate. The goal of this research is to produce nano-emulsions and nano-particles with the smallest obtainable size and polydispersity in a fully continuous two-stage process. In the first stage or emulsification stage, parameters like flowrate, residence time and acoustic power are varied to influence and determine the optimal energy density. In second stage or reaction stage, residence time and reaction temperature are studied to obtain particles of monodisperse sizes. Samples produced in both stages are analysed with Dynamic Light Scattering to measure the average size and polydispersity (PdI) of the emulsion droplets and particles. Emulsification results indicate that droplet size and PdI decreases at increasing energy densities (J/ml) until 60 J/ml after which a constant droplet size of 150 nm and PdI of 0.230 are reached. Furthermore, a particle size of 50 nm and PdI of 0.080 were achieved in both batch and continuous polymerization reactors after 5 min at 85 °C. By implementing the most optimal process parameters, small emulsion droplets and particles were obtained more energy efficient in a shorter emulsification and reaction time compared to literature ultrasound assisted nano-emulsion polymerization processes.

Questionnaire scales that are mixed-worded, i.e. include both positively and negatively worded items, often suffer from issues like low reliability and more complex latent structures than intended. Part of the problem might be that some responders fail to respond consistently to the mixed-worded items. We investigated the prevalence and impact of inconsistent responders in 37 primary education systems participating in the joint PIRLS/TIMSS 2011 assessment. Using the mean absolute difference method and three mixed-worded self-concept scales, we identified between 2%-36% of students as inconsistent responders across education systems. Consistent with expectations, these students showed lower average achievement scores and had a higher risk of being identified as inconsistent on more than one scale. We also found that the inconsistent responders biased the estimated dimensionality and reliability of the scales. The impact on external validity measures was limited and unsystematic. We discuss implications for the use and development of questionnaire scales.

The low-stakes character of international large-scale educational assessments implies that a participating student might at times provide unrelated answers as if s/he was not even reading the items and choosing a response option randomly throughout. Depending on the severity of this invalid response behavior, interpretations of the assessment results are at risk of being invalidated. Not much is known about the prevalence nor impact of such "random responders" in the context of international large-scale educational assessments. Following a mixture item response theory (IRT) approach, an initial investigation of both issues is conducted for the Confidence in and Value of Mathematics/Science (VoM/VoS) scales in the Trends in International Mathematics and Science Study (TIMSS) 2015 student questionnaire. We end with a call to facilitate further mapping of invalid response behavior in this context by the inclusion of instructed response items and survey completion speed indicators in the assessments and a habit of sensitivity checks in all secondary data studies.

Communication of International Large-Scale Assessment (ILSA) results is dominated by reporting average country achievement scores that conceal individual differences between pupils, schools, and items. Educational research primarily focuses on examining differences between pupils and schools, while differences between items are overlooked. Using a variance components model on the Programme for International Student Assessment (PISA) 2018 cognitive domains of reading, mathematics, and science literacy, we estimated how much of the response variation can be attributed to differences between pupils, schools, and items. The results show that uniformly across domains and countries, it mattered more for the correctness of an item response which items were responded to by a pupil (27-35%) than which pupil responded to these items (10-12%) or which school the pupil attended (5-7%). Given the findings, we argue that differences between items in ILSAs constitute a source of substantial untapped potential for secondary research.

Poor metaphor comprehension was considered a hallmark of autism spectrum disorder (ASD), but recent research has questioned the extent and the sources of these difficulties. In this cross-sectional study, we compared metaphor comprehension in individuals with ASD (N = 29) and individuals with typical development (TD; N = 31), and investigated the relationship between core language and metaphor comprehension. Individuals with ASD showed more difficulty but also a more variable performance in both metaphor and literal items of the task used than individuals with TD did. This indicates that core language ability accounts for metaphor comprehension and should be considered in future research and interventions aiming to improve metaphor comprehension in individuals with ASD.

Internet of Things (IoT) has proved its applicability in numerous domains, such as healthcare, agriculture, automobile, industrial production, logistics, and supply chain management. Looking at the current trend, we expect a massive proliferation of such IoT devices all around us. However, one of the issues with the widespread use of IoT is the increasing complexity of the underlying architecture, which leads to difficulty in ensuring security compliance. Key refreshment, one of the critical aspects of key management, requires a regular update of the key used to provide strong security. However, in most cases, keys are not updated. If they are updated, the update logs (e.g., time of last key update) are not available for all entities to verify and establish trust in the system. Moreover, the rules for key refreshment are also not defined transparently. In this direction, the present work proposes a blockchain-regulated, secure, verifiable, and automatic key refreshment mechanism for IoT systems. The proposed mechanism enables users to verify the freshness of the security keys (being used), thereby relying on the data from IoT devices and establishing trust in an IoT system. The proposed mechanism is driven by blockchain technology and smart contract. As proof of concept, we have implemented the proposed solution using Ethereum and Hyperledger Fabric blockchains. Cost, scalability, and security (formal and informal) analyses have been carried out for performance analysis. The results show the economic viability and strong security of the proposed mechanism.

The objective of this document was to standardise published cardiopulmonary exercise testing (CPET) protocols for improved interpretation in clinical settings and multicentre research projects. This document: 1) summarises the protocols and procedures used in published studies focusing on incremental CPET in chronic lung conditions; 2) presents standard incremental protocols for CPET on a stationary cycle ergometer and a treadmill; and 3) provides patients' perspectives on CPET obtained through an online survey supported by the European Lung Foundation. We systematically reviewed published studies obtained from EMBASE, Medline, Scopus, Web of Science and the Cochrane Library from inception to January 2017. Of 7914 identified studies, 595 studies with 26 523 subjects were included. The literature supports a test protocol with a resting phase lasting at least 3 min, a 3-min unloaded phase, and an 8- to 12-min incremental phase with work rate increased linearly at least every minute, followed by a recovery phase of at least 2-3 min. Patients responding to the survey (n=295) perceived CPET as highly beneficial for their diagnostic assessment and informed the Task Force consensus. Future research should focus on the individualised estimation of optimal work rate increments across different lung diseases, and the collection of robust normative data.

We examined the concurrent relationship between narrative skills (the Renfrew Bus Story Test) and core language measures (vocabulary, grammar and verbal memory) at age 4 and the longitudinal relationship between core language and listening comprehension skills at age 7 in a sample of 215 children using latent variables and structural equation modelling. Our main purpose was to investigate to what extent narrative retell constitutes a unique influence on later language and listening comprehension skills. The results support a two-factor model of narrative retelling and core language representing different but related constructs at age 4. Narrative retell explained unique variance in later language skills but did not explain additional variance beyond the 58% explained by the age 4 language construct. Similarly, narrative retell predicted unique variance in later listening comprehension, but not beyond what was explained by core language skills at age 4. The strength of the relationship between narrative retelling at age 4 and the age 7 measures was not related to the level of narrative skills. The results indicate that age 4 traditional core language measures capture more of the skills that are important for later language and listening comprehension than narrative skills at the same age.