Do sex differences in a faceted model of fluid and crystallized intelligence depend on the method applied?

Large-Scale Item-Level Analysis of the Figural Matrices Test in the Norwegian Armed Forces: Examining Measurement Precision and Sex Bias

Figural matrices tests are common in intelligence research and have been used to draw conclusions regarding secular changes in intelligence. However, their measurement properties have seldom been evaluated with large samples that include both sexes. Using data from the Norwegian Armed Forces, we study the measurement properties of a test used for selection in military recruitment. Item-level data were available from 113,671 Norwegian adolescents (32% female) tested between the years 2011 and 2017. Utilizing item response theory (IRT), we characterize the measurement properties of the test in terms of difficulty, discrimination, precision, and measurement invariance between males and females. We estimate sex differences in the mean and variance of the latent variable and evaluate the impact of violations to measurement invariance on the estimated distribution parameters. The results show that unidimensional IRT models fit well in all groups and years. There is little difference in precision and test difficulty between males and females, with precision that is generally poor on the upper part of the scale. In the sample, male latent proficiency is estimated to be slightly higher on average, with higher variance. Adjusting for measurement invariance generally reduces the sex differences but does not eliminate them. We conclude that previous studies using the Norwegian GMA data must be interpreted with more caution but that the test should measure males and females equally fairly.

Verbal and non-verbal skills in early childhood: dimensionality, developmental trajectories, and gender differences

This study examines the dimensionality of and relationships between two subscales from the British Ability Scales - Third Edition, measuring verbal (expressive vocabulary) and non-verbal (reasoning) cognitive skills for toddlers (age three) and preschoolers (age five), in a Norwegian context across genders. Descriptive statistics revealed item selection criteria that included specific items within each subscale. Subsequently, Confirmatory Factor Analysis established the subscales' dimensionality (Naming Vocabulary and Picture Similarities; N = 1094) and confirmed measurement invariance across genders. Further, the relationships between the verbal and non-verbal factors were investigated using correlation analysis and Structural Equation Modeling. The findings revealed that the verbal factor at age three strongly predicted the verbal factor at age five and significantly influenced the non-verbal factor at age five. The non-verbal factor at age three exhibited a moderate predictive relationship with the non-verbal factor at age five, and did not significantly predict the verbal factor at age five. In terms of gender differences, girls showed higher scores on the verbal factor at age three, and a stronger correlation between the non-verbal factor at age three and the verbal factor at age five. In summary, this research provides valuable insights into cognitive skill measurement and development in a Norwegian context and highlights possible variations across gender. The study's findings, limitations, and implications are discussed.

Intelligenz‍(tests) verstehen und missverstehen

Zusammenfassung. Die vorliegende Standortbestimmung zeigt die hohe wissenschaftliche Qualität der Intelligenzforschung und von Intelligenztests. Es werden aber auch mögliche Missverständnisse und Einseitigkeiten der Ergebnisrezeption und -interpretation thematisiert. Im Einzelnen werden (1) die hohe prognostische und kriterienbezogene Validität bei gleichzeitigen Vorbehalten wie teils niedriger Akzeptanz bzw. Augenscheinvalidität, (2) die Darstellung empirischer Befunde aus der Perspektive ausgewählter Theorien sowie (3) die Bedeutung von Umwelteinflüssen und hohen Erblichkeitskoeffizienten eingehender betrachtet. Für jeden dieser Bereiche wird verdeutlicht, dass vor allem Präzision bei der Rezeption und Darstellung von Forschungsergebnissen notwendig ist, um Einseitigkeiten, Missverständnisse und Instrumentalisierungen zu vermeiden. Der vorliegende Beitrag zeigt, dass einiges, was als Problem der Intelligenzforschung und von Intelligenztests kritisiert wird, letztendlich auf die dargestellten Missverständnisse zurückzuführen ist. Vor diesem Hintergrund wird der Unterschied zwischen der qualitativ hochwertigen Intelligenzforschung und Intelligenztestung einerseits sowie den Missverständnissen und Einseitigkeiten bei der Rezeption andererseits herausgearbeitet. Weiterhin werden berechtigte Kritikpunkte an der Intelligenzforschung und an Intelligenztests sowie Forschungsdesiderata benannt.

The neurocognitive correlates of brain entropy estimated by resting state fMRI

Resting state brain activity consumes most of brain energy, likely creating and maintaining a reserve of general brain functionality. The latent reserve if it exists may be reflected by the profound long-range fluctuations of resting brain activity. The long-range temporal coherence (LRTC) can be characterized by resting state fMRI (rsfMRI)-based brain entropy (BEN) mapping. While BEN mapping results have shown sensitivity to neuromodulations or disease conditions, the underlying neuromechanisms especially the associations of BEN or LRTC to neurocognition still remain unclear. To address this standing question and to test a novel hypothesis that resting BEN reflects a latent functional reserve through the link to general functionality, we mapped resting BEN of 862 young adults and comprehensively examined its associations to neurocognitions using data from the Human Connectome Project (HCP). Our results unanimously highlighted two brain circuits: the default mode network (DMN) and executive control network (ECN) through their negative associations of BEN to general functionality, which is independent of age and sex. While BEN in DMN/ECN increases with age, it decreases with education years. These results demonstrated the neurocognitive correlates of resting BEN in DMN/ECN and suggest resting BEN in DMN/ECN as a potential proxy of the latent functional reserve that facilitates general brain functionality and may be enhanced by education.

Sex Differences in Intelligence in Children Aged 2:6–7:7: Analysis of the Factor Structure and Measurement Invariance of the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition

The present study investigated gender differences in cognitive abilities for children aged 2–7 years on the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition (WPPSI-IV). WPPSI-IV data of 1,042 children (517 girls and 525 boys) were selected from the extended dataset of the German WPPSI-IV standardization sample. First of all, confirmatory factor analyses (CFAs) were used to verify the factor structure of the WPPSI-IV, which was proposed by the test developers. Then, multiple-group confirmatory factor models were implemented to explore measurement invariance across gender. Finally, mean differences in the subtests, index scores, as well as full scale IQ (FSIQ) were analyzed. The second-order three-factor model for age group 2:6–3:11 as well as the second-order five-factor model for age group 4:0–7:7 could be verified. For age group 2:6–3:11, full scalar invariance could be accepted, whereas partial scalar invariance could be established by freeing five nonequivalent subtest intercepts for age group 4:0–7:7. These findings support interpretable comparisons of the WPPSI-IV scores between girls and boys. For age group 4:0–7:7, partial invariance should be taken into account in these comparisons. Furthermore, girls aged 4:0–7:7 showed an advantage in processing speed (PS). Mean scores in any of the other cognitive abilities did not differ between girls and boys in both age groups. These results indicated measurement invariance across gender on the WPPSI-IV, so that the tests measure cognitive abilities in the same way for girls and boys. The current findings showed that gender differences in PS may emerge in early childhood, which might lead to gender differences in later educational skills.

Development of Subjective Well-Being in Adolescence

Despite the importance of subjective well-being (SWB) for students' mental and physical health, there is a lack of longitudinal studies investigating the development of SWB in adolescents and what factors are associated with it over time. The present study seeks to shed further light on this question by investigating adolescents longitudinally. A sample of German academic tracks students (N = 476) from five schools were followed longitudinally over a time period of 30 months with four measurement points from Grade 11 to Grade 13. Alongside the longitudinal assessment of SWB (mood and life satisfaction), a range of other factors were also assessed at t1 including; demographic factors (sex, age, socio-economic status (HISEI)), intelligence, grades (report cards provided by the schools), personality (neuroticism, extraversion) and perceived parental expectations and support. Latent growth curve models were conducted to investigate the development of SWB and its correlates. On average, mood and life satisfaction improved at the end of mandatory schooling. However, students significantly differed in this pattern of change. Students' life satisfaction developed more positively if students had good grades at t1. Furthermore, even though introverted students started with lower life satisfaction at t1, extraverts' life showed greater increases over time. Changes in mood were associated with socio-economic background; the higher the HISEI the more positive the change. As social comparisons in school performance are almost inevitable, schools should intervene to buffer the influence of school grades on students' SWB.

Why Time Constraints Increase the Gender Gap in Measured Numerical Intelligence in Academically High Achieving Samples

Abstract. Gender differences in the numerical domain vary greatly according to the assessment method used. We suggest that strict time constraints, as employed on most numerical intelligence tests but not on mathematical competency tests, unduly increase the gender gap in measured numerical intelligence if the test focuses reasoning. Two studies were conducted. First, 666 11th and 12th graders were randomly assigned to speeded or nonspeeded versions of verbal, figural, and numerical reasoning tests. Extending the test time reduced gender differences in numerical but not in verbal and figural reasoning. To rule out ceiling effects and to test for potential motivational and emotional effects on test performance, a second sample of 542 students completed both a speeded and a nonspeeded numerical reasoning test as well as several motivational and emotional questionnaires. In the nonspeeded condition, girls increased their performance more than boys. This effect was especially strong for female students with medium and high performances and was largely but not fully explained by emotional and motivational factors. We conclude that girls are prevented from showing their actual potential on speeded numerical reasoning tests.

Second language acquisition effects of a primary physical education intervention: A pilot study with young refugees

BACKGROUND

A physical education (PE) intervention for young refugees was designed combining physical activity within the context of primary PE games with second language learning activities in German. The intervention was based on theoretical implications from the field of second language acquisition and evidence for positive effects of physical activity on cognitive outcomes (e.g. language acquisition). The aim of this study was to analyze short term effects on second language acquisition.

METHODS

Sixty-one young refugees were included in the study (age: 8.5 ± 1.4 years). The intervention group participated in language-enriched PE lessons based on an elaborated approach to second language learning acquisition. The control group did not receive any treatment. Both groups were pre-and post-tested in domain specific vocabulary, listening comprehension and use of local prepositions within the context of primary PE games.

RESULTS

Results from linear mixed-effect modelling suggest that the intervention group significantly improved domain specific vocabulary and listening comprehension in comparison to the control group.

CONCLUSIONS

The intervention was successful since the PE lessons contributed to the second language acquisition of young refugees. Therefore, this learning approach might also be useful for physical activity based second language learning activities in other PE contexts for early second language learners in primary school.

Personality and Intelligence Interact in the Prediction of Academic Achievement

Personality predicts academic achievement above and beyond intelligence. However, studies investigating the possible interaction effects between personality and intelligence when predicting academic achievement are scarce, as is the separate investigation of broad personality factors versus narrow personality facets in this context. Two studies with 11th grade students (Study 1: N = 421; Study 2: N = 243) were conducted to close this research gap. The students completed the Intelligence-Structure-Test 2000 R measuring general reasoning ability, and a well-established personality inventory based on the Five Factor Model. Academic achievement was operationalized via Grade Point Average. Using hierarchical regression and moderation analyses, Study 1 revealed that Conscientiousness interacted with intelligence when predicting academic achievement: there was a stronger association between intelligence and academic achievement when students scored higher on the Conscientiousness scale. Study 2 confirmed the findings from Study 1 and also found a moderation effect of Neuroticism (stronger association between intelligence and academic achievement with lower values on the Neuroticism scale). Analyses at the facet level revealed much more differentiated results than did analyses at the domain level, suggesting that investigating personality facets should be preferred over investigating personality domains when predicting academic achievement.

Sex differences in the intellectual functioning of early school-aged children in rural China

Background

Gender disparities in China are concentrated in poor rural areas and among poor households. The difference in intelligence between boys and girls is less clear in rural China. The purpose of this paper was to assess sex differences in the intellectual function of early school-aged children in rural China.

Methods

One thousand seven hundred forty four early school-aged offspring of women who had participated in a prenatal supplementation trial with different combinations of micronutrients and continued to reside in two rural counties in China were followed. We measured their Full-Scale IQ (FSIQ), Verbal Comprehension Index (VCI), Working Memory Index (WMI), Perceptual Reasoning Index (PRI) and Processing Speed Index (PSI) using the Wechsler Intelligence Scale for Children (WISC-IV). Multilevel analyses were used to assess sex differences in intellectual functioning in 7-10-year-old children in rural China.

Results

Boys’ adjusted mean FSIQ score was 0.97 points higher (95 % CI: -2.22 − 0.28) than that of girls. Girls obtained higher mean WMI and PSI scores, with 1.32 points (95 % CI: 0.14 − 2.51) and 3.10 points (95 % CI: 1.82–4.38) higher adjusted means, respectively. Boys’ adjusted mean VCI and PRI scores were significantly higher than those of girls, and the mean differences were 2.44 points (95 % CI: 0.95 − 3.94) and 3.68 points (95 % CI: 2.36 − 5.01), respectively.

Conclusions

There is no evidence to suggest sex differences in the general intelligence of early school-aged children in rural China. However, a difference in general intelligence between 10-year-old boys and girls was evident. Girls and boys in rural China tended to show different specific cognitive abilities.

Are gifted adolescents more satisfied with their lives than their non-gifted peers?

Studies investigating the life satisfaction of intellectually gifted and non-gifted students are scarce and often suffer from methodological shortcomings. We examined the life satisfaction of gifted and non-gifted adolescents using a rather unselected sample of N = 655 German high-school students (n = 75 gifted), adequate comparison groups of non-gifted students, and a clear definition of giftedness (general intelligence g > 2 SD above the mean). There was no difference in life satisfaction between gifted and non-gifted adolescents (d < |0.1|). Girls reported somewhat lower life satisfaction scores than boys (d = 0.24). However, this result was not specific to giftedness but was instead found across the entire sample. Thus, gifted girls were not found to be especially unsatisfied with their lives. Our findings support previous research showing that giftedness is not a risk factor for impaired psycho-social well-being of boys or girls.

Sex differences in general knowledge: meta-analysis and new data on the contribution of school-related moderators among high-school students

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge.

The Relationship Between Cognitive Ability and Demographic Factors in Late Midlife

Objective: The aim of the article is to analyze associations between sex, age, education, and social class and cognitive ability in late midlife and to evaluate differences in cognitive ability among the three Copenhagen Aging and Midlife Biobank (CAMB) cohorts. Method: The sample comprised 5,417 CAMB participants from three cohorts with scores on the Intelligenz-Struktur-Test 2000 R (I-S-T 2000 R). Results: Independent associations of cognitive ability with age, sex, education, and occupational social class were observed. Particularly, strong associations with cognitive ability were obtained for school education, and consistent sex differences were observed with higher cognitive ability in men. Differences in cognitive ability among the three cohorts were small and primarily reflected demographic differences. Discussion: Late-midlife cognitive ability is associated with a number of demographic factors, and demographic differences may contribute to individual differences in health and early aging. In analyses of cognitive ability, the three CAMB cohorts can be combined provided the relevant demographic variables are included as covariates.