Sex differences in latent cognitive abilities ages 6 to 59: Evidence from the Woodcock–Johnson III tests of cognitive abilities

Multiple domain-general assessments of cognitive functions in elite athletes: Contrasting evidence for the influence of expertise, sport type and sex

Converging evidence has shown that domain-general cognitive abilities, especially executive functions (EF), tend to be superior in sport experts. However, recent studies have questioned this cognitive advantage and found inconsistent findings when comparing sport type and sex. This study aimed to compare the impact of sport expertise, sport type, and sex on various domains of cognitive functions. Two hundred and thirty elite athletes (nFemale = 124, nMale = 106) representing three sport categories (Team [n = 91], Precision-skill dependent [n = 63], and Speed-strength [n = 76] sports) were assessed using a computerized neuropsychological test battery including tests of EF (working memory, inhibition, cognitive flexibility and planning), as well as tests of selective and sustained attention. T-scores and raw values were used to analyze performance through t-tests and ANCOVA with age as covariate. Athletes demonstrated better performance than the normative mean on 5 out of 11 cognitive test variables (p < 0.005). However, their performance fell within the average range when considering the results along a normative scale, except for sustained attention and working memory where they performed just above average (<1 SD). There was a significant main effect of sport category on only one EF variable (p = 0.003). Males performed significantly faster than females on motor reaction time measures of attention and inhibition (all p < 0.001). In this study, the 'expert advantage' on domain-general cognitive tests was less prominent when utilizing a normative scale and controlling for age or speed-accuracy trade-offs, except for sustained attention and working-memory. Cognitive functions did not appear to differ meaningfully based on athletes' sport type or sex.

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.

Gender Differences in the Wechsler Intelligence Scale for Children in a Large Group of Italian Children with Attention Deficit Hyperactivity Disorder

Despite being repeatedly investigated in children with typical development, research on gender differences in intellectual abilities in specific groups of children, including children with attention deficit hyperactivity disorder (ADHD), has been scarce. In this paper, we evaluated the performance of a large group of Italian children with ADHD using the WISC-IV. We aimed at investigating the presence of gender differences using a multi-group confirmatory factor analysis approach. Results showed that the WISC is largely gender-invariant. However, some tasks present non-invariant patterns (block design and coding). Differences at the latent level also showed some differences (favoring boys) in the verbal comprehension index. Conversely, differences at the latent level were not found in the full-scale IQ or in the other main indices. These results have theoretical and practical implications.

The Nomological Net of Knowledge, Self-Reported Knowledge, and Overclaiming in Children

Research on self-reported knowledge and overclaiming in children is sparse. With the current study, we aim to close this gap by developing an overclaiming questionnaire measuring self-reported knowledge and overclaiming that is tailored to children. Moreover, we examine the nomological net of self-reported knowledge and overclaiming in childhood discussing three perspectives: Overclaiming as (a) a result of deliberate self-enhancement tendencies, (b) a proxy for declarative knowledge, and (c) an indicator of creative engagement. We juxtaposed overclaiming, as indicated by claiming familiarity with non-existent terms, and self-reported knowledge with fluid and crystallized intelligence, creativity, and personality traits in a sample of 897 children attending third grade. The results of several latent variable analyses were similar to findings known from adult samples: We found no strong evidence for any of the competing perspectives on overclaiming. Just like in adults, individual differences in self-reported knowledge were strongly inflated by overclaiming, and only weakly related to declarative knowledge.

Factorial Invariance of the Anadolu Sak Intelligence Scale Across Gender

The purpose of this study was to examine the factorial invariance of the ASIS (Anadolu Sak Intelligence Scale) across gender. Raw scores from the ASIS standardization study ( N = 4641) were used in the analyses. Factorial invariance was analyzed by gender across three age groups: 4–7 ( N = 2528), 8–9 ( N = 848), and 10–12 ( N = 1265) using the Multisample Confirmatory Factor Analysis. Six models were developed from unconstrained to more constrained to test the factorial invariance. Each model tested one hypothesis. The findings showed that the second-order g model of the ASIS was invariant in all age groups. In addition, the first-order and second-order factor loadings and g variance were invariant across gender. A partial subtest intercept invariance was found for ages 4–7. Findings imply that ASIS factor scores mean the same latent variable for boys and girls in different age groups.

Latent structure of cognitive tests is invariant in men and women with schizophrenia

Studies comparing the cognitive functioning of men and women with schizophrenia have produced conflicting results which could arise from sex-based differences in the latent structure of cognitive abilities. The current study used multigroup confirmatory factor analysis to examine invariance in latent structure of cognitive abilities to between men and women with schizophrenia. Confirmatory factor analysis of an initial neurocognitive assessment (men n = 612, women n = 201) and cross-validation using second assessment (men n = 549, women n = 198) demonstrated that a bifactor seven-factor model fit the data best for both men and women. Invariance analyses further indicated this model was invariant across men and women at both assessments. Group comparisons indicated women had significantly higher scores for Semantic Memory, Verbal Memory, and General Cognitive factors, whereas men exhibited better performance on the Vigilance factor. Results indicate that cognition in SZ is characterized by both a general cognitive factor and specific domains for both men and women. Invariance analysis provides evidence that cognitive differences between men and women do not result from sex-based differences in the latent structure of cognitive abilities. Current results also indicate small but statistically significant neurocognitive differences between men and women with schizophrenia.

The Impasse on Gender Differences in Intelligence: a Meta-Analysis on WISC Batteries

This meta-analysis reviews 79 studies (N = 46,605) that examined the existence of gender difference on intelligence in school-aged children. To do so, we limited the literature search to works that assessed the construct of intelligence through the Wechsler Intelligence Scales for Children (WISC) batteries, evaluating eventual gender differences in indices and subtests. The theoretical framework we adopted is the cross-battery approach which locates cognitive abilities into different levels, also considering the possible mediating effect of the version of the WISC being used. As for broad abilities, a notable discrepancy emerged in favour of males for visual and crystallized intelligence, while female/male differences on fluid intelligence were negligible. Conversely, females’ performance on the processing speed factor was superior. Interesting results emerged at the subtest levels, albeit with less pronounced differences in performance. Results generally showed that older versions of WISC batteries displayed larger gender differences compared to the most recent ones.

The sexual brain, genes, and cognition: A machine-predicted brain sex score explains individual differences in cognitive intelligence and genetic influence in young children

Sex impacts the development of the brain and cognition differently across individuals. However, the literature on brain sex dimorphism in humans is mixed. We aim to investigate the biological underpinnings of the individual variability of sexual dimorphism in the brain and its impact on cognitive performance. To this end, we tested whether the individual difference in brain sex would be linked to that in cognitive performance that is influenced by genetic factors in prepubertal children (N = 9,658, ages 9-10 years old; the Adolescent Brain Cognitive Development study). To capture the interindividual variability of the brain, we estimated the probability of being male or female based on the brain morphometry and connectivity features using machine learning (herein called a brain sex score). The models accurately classified the biological sex with a test ROC-AUC of 93.32%. As a result, a greater brain sex score correlated significantly with greater intelligence (p_fdr  < .001, η p 2 $$ {\eta}_p^2 $$  = .011-.034; adjusted for covariates) and higher cognitive genome-wide polygenic scores (GPSs) (p_fdr  < .001, η p 2 $$ {\eta}_p^2 $$  < .005). Structural equation models revealed that the GPS-intelligence association was significantly modulated by the brain sex score, such that a brain with a higher maleness score (or a lower femaleness score) mediated a positive GPS effect on intelligence (indirect effects = .006-.009; p = .002-.022; sex-stratified analysis). The finding of the sex modulatory effect on the gene-brain-cognition relationship presents a likely biological pathway to the individual and sex differences in the brain and cognitive performance in preadolescence.

Age and Sex Invariance of the Woodcock-Johnson IV Tests of Cognitive Abilities: Evidence from Psychometric Network Modeling

The Woodcock-Johnson IV Tests of Cognitive Abilities (WJ IV COG) is a comprehensive assessment battery designed to assess broad and narrow cognitive abilities, as defined by the Cattell-Horn-Carroll (CHC) theory of intelligence. Previous studies examined the invariance of the WJ assessments across sex and age groups using factor analytic methods. Psychometric network modeling is an alternative methodology that can address both direct and indirect relationships among the observed variables. In this study, we employed psychometric network modeling to examine the invariance of the WJ IV COG across sex and age groups. Using a normative sample (n = 4212 participants) representative of the United States population, we tested the extent to which the factorial structure of the WJ IV COG aligned with CHC theory for the school-aged sample. Next, we used psychometric network modeling as a data-driven method to investigate whether the network structure of the WJ IV COG remains similar across different sex and age (age 6 to 19, inclusively) groups. Our results showed that the WJ IV COG maintained the same network structure across all age and sex groups, although the network structure at younger ages indicated weaker relationships among some subtests. Overall, the results provide construct validity evidence for the WJ IV COG, based on both theoretical and data-driven methods.

Twins Assessing Their Own and Parental Intelligence: Examining the Raters' Agreement and the Effect of Raters' and Targets' Gender

The goal of this study was to explore the raters' agreement and the effect of raters' and targets' gender on self- and parental intelligence assessments in the sample of Croatian twins. Twins were asked to assess their own and their parents' overall intelligence, as well as specific abilities from the Gardner's theory of multiple intelligences. Data was analysed to explore: i) twins' agreement in parental assessments and behavioural genetic analysis of the overall intelligence estimates; ii) gender differences in self- assessments; and iii) raters' and targets' gender effects on parental assessments. The twins' mean correlation in their assessments of overall parental intelligence was .60. The differences between monozygotic and dizygotic twin correlations were nonsignificant for all of the estimated abilities, and model fitting analysis indicates that hypothesis about genetic effect on parental assessment of intelligence should be rejected. The hypotheses about males' higher self-assessments for overall intelligence and for the masculine types of abilities - logical-mathematical, body-kinesthetic and spatial abilities - were confirmed. For the feminine types of abilities - verbal/linguistic, inter- and intra- personal intelligences - there were no significant gender effects. Both target and rater effect were found for the parental estimates of intelligence. Fathers were estimated higher on overall intelligence, logical-mathematical, body-kinesthetic and spatial abilities, while mothers were estimated higher on interpersonal and intrapersonal intelligence. The effect of the raters' gender was found for overall intelligence as well as for inter- and intra- personal intelligences, where males gave higher estimates of parental intelligences than females.

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.

Age and Gender Invariance in the Taiwan Wechsler Intelligence Scale for Children, Fifth Edition: Higher Order Five-Factor Model

This study investigated the factorial invariance of the Taiwan Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) across age and gender. A higher order five-factor model was tested on a nationally representative sample of 1,034 children aged 6–16 years. The results demonstrated full factorial invariance for Taiwan children of different ages and gender. The WISC-V subtests demonstrated the same underlying theoretical latent constructs, strength of relations among factors and subtests, validity of each first-order factor, and communalities, regardless of age and gender, which supported the same interpretive approach of the WISC-V. These results accord with findings in the United States, indicating a full factorial invariance of the WISC-V five-factor structure across ages and gender.

Sex Similarities and Differences in Intelligence in Children Aged Two to Eight: Analysis of SON-R 2-8 Scores

The aim of this study was to investigate sex similarities and differences in visuospatial and fluid abilities and IQ scores based on those abilities in children aged two to eight. Standardization data from the Snijders-Oomen Nonverbal Intelligence Test for Children aged 2-8 (SON-R 2-8) were used. A representative sample composed of 965 children from the Netherlands and 762 children from Germany was examined. Small but significant mean sex differences favoring girls were observed until age four. At ages six and seven, boys achieved similar cognitive development levels to girls regarding all abilities assessed and outperformed girls on the Mosaics subtest measuring visuospatial cognition. Boys also displayed higher variability rates in performance. The distribution of IQ scores, with the overrepresentation of girls scoring above mean and the overrepresentation of boys scoring below mean in early childhood, altered with age towards parity between the sexes. The results suggest that girls tend to mature earlier with respect to cognitive abilities. During the course of development, however, the differences between girls and boys may become negligible.

Geschlechtsinvarianz und Geschlechtsdifferenzen in der Intelligenzeinschätzung mit den Intelligence and Development Scales

Zusammenfassung. Die Studie untersucht die Messinvarianz über das Geschlecht und Geschlechtsdifferenzen in der Intelligenz mit den Intelligence and Development Scales-Preschool (IDS-P; Grob, Reimann, Gut & Frischknecht, 2013 ) und Intelligence and Development Scales (IDS; Grob, Meyer & Hagmann-von Arx, 2013 ). Die IDS-P (3.0 to 5.11) und IDS (5.0 to 10.11) erfassen die allgemeine Intelligenz anhand von 7 Untertests. Die Studie verwendete die Normierungsstichproben mit N(IDS-P) = 700 und N(IDS) = 1 330 (je 50 % Jungen). Beide Verfahren wiesen latente partielle Messinvarianz auf Ebene der Untertests sowie auf Ebene der allgemeinen Intelligenz auf. Auf manifester Ebene zeigten sich keine Mittelwertdifferenzen für die allgemeine Intelligenz. In einigen Untertests ergaben sich Unterschiede zwischen den Geschlechtern: Jungen zeigten im Durchschnitt in Denken Bildlich in beiden Verfahren, Mädchen in Aufmerksamkeit Selektiv und in Gedächtnis Auditiv bessere Leistungen in den IDS-P. Die manifesten Varianzen unterschieden sich nicht. Die Befunde belegen, dass die Verfahren invariant bezüglich ihrer Struktur über das Geschlecht sind und folglich eine faire Intelligenzeinschätzung für beide Geschlechter ermöglichen.

Does the Cognitive Reflection Test actually capture heuristic versus analytic reasoning styles in older adults?

Background/Study Context: This study evaluated adult age differences in the original three-item Cognitive Reflection Test (CRT; Frederick, 2005, The Journal of Economic Perspectives, 19, 25-42) and an expanded seven-item version of that test (Toplak et al., 2013, Thinking and Reasoning, 20, 147-168). The CRT is a numerical problem-solving test thought to capture a disposition towards either rapid, intuition-based problem solving (Type I reasoning) or a more thoughtful, analytical problem-solving approach (Type II reasoning). Test items are designed to induce heuristically guided errors that can be avoided if using an appropriate numerical representation of the test problems.

METHODS

We evaluated differences between young adults and old adults in CRT performance and correlates of CRT performance. Older adults (ages 60 to 80) were paid volunteers who participated in experiments assessing age differences in self-regulated learning. Young adults (ages 17 to 35) were students participating for pay as part of a project assessing measures of critical thinking skills or as a young comparison group in the self-regulated learning study.

RESULTS

There were age differences in the number of CRT correct responses in two independent samples. Results with the original three-item CRT found older adults to have a greater relative proportion of errors based on providing the intuitive lure. However, younger adults actually had a greater proportion of intuitive errors on the long version of the CRT, relative to older adults. Item analysis indicated a much lower internal consistency of CRT items for older adults.

CONCLUSION

These outcomes do not offer full support for the argument that older adults are higher in the use of a "Type I" cognitive style. The evidence was also consistent with an alternative hypothesis that age differences were due to lower levels of numeracy in the older samples. Alternative process-oriented evaluations of how older adults solve CRT items will probably be needed to determine conditions under which older adults manifest an increase in the Type I dispositional tendency to opt for superficial, heuristically guided problem representations in numerical problem-solving tasks.

Cognitive ability influences on written expression: Evidence for developmental and sex-based differences in school-age children

Some studies have demonstrated that the Cattell-Horn-Carroll (CHC) cognitive abilities influence writing; however, little research has investigated whether CHC cognitive abilities influence writing the same way for males and females across grades. We used multiple group structural equation models to investigate whether CHC cognitive ability influences on written expression differed between grades or sex using the Kaufman Assessment Battery for Children, Second Edition and the Kaufman Tests of Educational Achievement, Second Edition co-normed standardization sample data (N=2117). After testing for consistent measurement of cognitive abilities across grades and sex, we tested whether the cognitive ability influences on written expression were moderated by grade level or sex. An important developmental shift was observed equally across sex groups: Learning Efficiency (Gl) influences decreased whereas Crystallized Ability (Gc) influences increased after fourth grade. Further, Short-Term Memory (Gsm) and Retrieval Fluency (Gr) influences on written expression depended on sex at grades 1-4, with larger Gr influences for females and larger Gsm influences for males. We internally replicated our main findings using two different cognitive explanatory models, adding further support for the developmental and sex-based differential cognitive ability influences on writing. Explanatory cognitive models of writing need to incorporate development, and possibly, sex to provide an expanded understanding of writing development and guard against potential generalizability issues characteristic of special population (i.e., male-female) studies.

Interactions between Sex, Socioeconomic Level, and Children's Cognitive Performance

This study assesses the interactions between sex, socioeconomic level, and children’s cognitive performance. Cognitive performance was measured for a sample of 453 Portuguese children, aged between 4 and 10 years, with 218 boys and 235 girls; verbal and nonverbal cognitive ability and intelligence quotient were measured by the Cognitive Skills Scale for Children. Multivariate analysis of variance assessed the effects of sex and family’s socioeconomic level on intelligence quotient. A statistically significant interaction between sex and socioeconomic level was observed for nonverbal intelligence quotient, total intelligence quotient, and two subtests. Socioeconomic level had more influence than sex on most of the cognitive tests.

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.

Geschlechtseffekte bei Intelligenz- und Gedächtnisleistungen

Diese Studie untersucht die Zusammenhänge von Intelligenz- und Gedächtnisleistungen in der Wechsler Adult Intelligence Scale-IV und der Wechsler Memory Scale-IV unter Berücksichtigung des Geschlechts (N = 137 Gesunde, 63 w/74 m). Ein Vorteil der weiblichen Testpersonen im verbalen episodischen Gedächtnis sowie in einzelnen Aufgaben zur Verarbeitungsgeschwindigkeit konnte beobachtet werden. Die männlichen Testpersonen schnitten in den Untertests Allgemeines Wissen und Visuelle Puzzles besser ab. Wie gut Gedächtnisleistungen Intelligenzleistungen erklären beziehungsweise vorhersagen, ist aufgrund unserer Ergebnisse nicht nur abhängig von den Aufgaben, sondern auch vom Geschlecht.

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.

International note: what factors are associated with reading, mathematics, and science literacy of Indian adolescents? A multilevel examination

A sample of 15-year-olds in India took part in the Program for International Student Assessment (PISA) for the first time in 2010. The PISA reading, mathematics, and science literacy scores of Indian adolescents were considerably lower than their counterparts in most PISA participating countries. In order to explore potential reasons for this, the present study, therefore, drawing on data from the fourth cycle of PISA and employing multilevel modeling, examined the relations of student- and school-level factors to reading, mathematics, and science literacy among 4826 15-year-old students from 213 schools in India. Gender, metacognitive learning strategies, students' positive attitudes toward school, and students' positive perceptions of classroom climate were found to be significantly associated with Indian adolescents' performance on the PISA assessment.