Pervasiveness of the IQ rise: a cross-temporal meta-analysis

Increasing IQ Test Scores and Decreasing g: The Flynn Effect and Decreasing Positive Manifold Strengths in Austria (2005-2018)

After almost a century of global generational IQ test score gains, the Flynn effect has, in the past decades, been observed to show stagnation and reversals in several countries. Tentative evidence from academic achievement data has suggested that these trajectory changes may be rooted in a decreasing strength of the positive manifold of intelligence due to increasing ability differentiation and specialization in the general population. Here, we provide direct evidence for generational IQ test score and positive manifold strength changes based on IQ test standardization data from 1392 Austrian residents between 2005 and 2018. Our analyses revealed positive Flynn effects across all domains of the IQ test (Cohen's d from 0.21 to 0.91) but a trend toward decreasing strength in the positive manifold of intelligence (R2 from .908 to .892), though these changes were not statistically significant. Our results are consistent with the idea that increasingly inconsistent Flynn effect trajectories may be attributed to increasing ability differentiation and specialization in the general population over time.

A Farewell to the Narcissism Epidemic? A Cross-Temporal Meta-Analysis of Global NPI Scores (1982-2023)

OBJECTIVE

Several recent accounts have failed to replicate the so-called Narcissism Epidemic, suggesting potential influences of the Global Financial Crisis (GFC) in 2008 as a reason for narcissism trend reversals. Here, we provide evidence for narcissism test score changes from 1982 to 2023.

METHODS

We investigated self-report data on the Narcissistic Personality Inventory (NPI) from 1105 studies (k = 1621, N = 546,225) using precision-weighted cross-temporal meta-analysis.

RESULTS

Data collection years were meaningfully negatively associated with narcissism scores in virtually all analyses (bs: -0.409 to -0.008; partial eta square's: < 0.001 to 0.118; ps: < 0.001 to 0.174), thus indicating cross-temporally decreasing narcissism self-report scores. Examination of regression segments pre- and post-dating the GFC and segmented line regressions indicated mostly stable narcissism scores during the 1980s and 1990s that subsequently showed negative slopes with somewhat differing decreases onsets according to analytical subsets.

CONCLUSIONS

Here, we provide evidence for negative cross-temporal changes in narcissism from 1982 to 2023 globally, thus contrasting the idea of a Narcissism Epidemic having taken place at any point during the past four decades. Changes appear to generalize across different regions and participant sex, although mean scores were differentiated, yielding higher narcissism values for North American and younger samples.

Increasingly capable at the ripe old age? Cognitive abilities from 2004 to 2013 in Germany, Spain, and Sweden

Background

Life expectancy is increasing in most high-income countries, but gains in life years are maximized if spent in good health and if cognitive abilities are maintained until old age. Age-related decline of cognitive abilities does nevertheless occur, but the pace of decline is decisive. This was the starting point for our study that aims to examine cohort effects of cognitive aging in women and men in Germany, Spain and Sweden by analyzing changes from 2004 to 2013 by estimating cohort effects within age groups starting from the age of 50 years.

Methods

A cohort study was conducted that was based on data of the surveys 2004 (N = 6,081) and 2013 (N = 8,650) from the Survey of Health, Ageing and Retirement in Europe (SHARE). The analyses were based on data of female and male respondents aged 50 years and older. Age-specific means of verbal fluency and delayed recall from the German, Spanish and Swedish samples were the cognitive domains considered in the study.

Results

In both domains of cognitive ability the achievements in the later surveys were higher than in the earlier ones. This was found in all countries, abut achievement levels increased markedly in the German and the Spanish samples, while the scores of the Swedish samples were not significantly different.

While the highest scores were found for Sweden, Germany ranked in the middle and the lowest scores were found in the Spanish samples. Over time, the scores of the German samples approached those of Sweden.

Conclusions

From the first to the second survey, improvements of older adults’ cognitive abilities were found for all countries considered. This may indicate improvements of the underlying educational systems, but also increasingly stimulating general living conditions.

A cross-temporal meta-analysis review of the personality of Chinese military personnel, 1991-2017

OBJECTIVE

The personality of military personnel is an important factor for their mental health. It has been revealed that military personnel's mental health has changed over the past decades. The objective of the present study was to examine the birth cohort changes in the personality of Chinese military personnel.

METHODS

To examine the birth cohort changes in the personality of Chinese military personnel, a cross-temporal meta-analysis of 53 studies that measured the personality of Chinese military personnel with the Eysenck Personality Questionnaire from 1991 to 2017 was conducted (61 data points, N = 55 708).

RESULTS

The results showed that during this period, the respondents' personality traits changed significantly. Specifically, their levels of neuroticism and psychoticism decreased by 0.84 and 0.62 standard deviations respectively, and the younger participants exhibited higher levels of extraversion.

CONCLUSIONS

This study found that Chinese military personnel showed decreasing neuroticism and psychoticism from 1991 to 2017 and that younger participants exhibited higher levels of extraversion. © 2020 John Wiley & Sons, Ltd.

Episodic Memory and Verbal Fluency Tasks: Normative Data from Nine Nationally Representative Samples

OBJECTIVE

This study aims to generate country-specific norms for two episodic memory tasks and a verbal fluency test among middle-aged and older adults using nationally representative data from nine low-, middle-, and high-income countries.

METHOD

Data from nine countries in Africa, Asia, Europe, and Latin America were analyzed (n = 42,116; aged 50 years or older). Episodic memory was assessed with the word list memory (three trials of immediate recall) and word list recall (delayed recall). Verbal fluency was measured through the animal naming task. Multiple linear regression models with country-specific adjustments for gender, age, education, and residential area were carried out.

RESULTS

Both age and education showed high influence on test performance (i.e. lower cognitive performance with increasing age and decreasing years of education, respectively), while the effect of sex and residential area on cognitive function was neither homogeneous across countries nor across cognitive tasks.

CONCLUSIONS

Our study provided sex-, age-, education-, and residential area-specific regression-based norms that were obtained from one of the largest normative study worldwide on verbal recall and fluency tests to date. Findings derived from this study will be especially useful for clinicians and researchers based at countries where cognitive norms are limited.

One Century of Global IQ Gains: A Formal Meta-Analysis of the Flynn Effect (1909-2013)

The Flynn effect (rising intelligence test performance in the general population over time and generations) varies enigmatically across countries and intelligence domains; its substantive meaning and causes remain elusive. This first formal meta-analysis on the topic revealed worldwide IQ gains across more than one century (1909-2013), based on 271 independent samples, totaling almost 4 million participants, from 31 countries. Key findings include that IQ gains vary according to domain (estimated 0.41, 0.30, 0.28, and 0.21 IQ points annually for fluid, spatial, full-scale, and crystallized IQ test performance, respectively), are stronger for adults than children, and have decreased in more recent decades. Altogether, these findings narrow down proposed theories and candidate factors presumably accounting for the Flynn effect. Factors associated with life history speed seem mainly responsible for the Flynn effect's general trajectory, whereas favorable social multiplier effects and effects related to economic prosperity appear to be responsible for observed differences of the Flynn effect across intelligence domains.

Urban Older Adults Becoming Unhealthier in Modern China: A Cross-Temporal Meta-Analysis

This study investigated patterns of change in the health status of urban older adults in urban China from 2001 to 2013. A cross-temporal meta-analysis was applied to 111 selected studies in which the SF-36 had been administered to urban older adults in China. Scores from a total of 72,441 participants were analyzed. Correlations between the SF-36 scores and sampling years were examined. The self-reported health status of urban older adults in China has declined significantly in the past 13 years. The observed decline in the health status of older adults suggests that economic progress and a rapidly aging population have had more negative than positive effects on the health of this population.

Changes of anxiety in Chinese military personnels over time: a cross-temporal meta-analysis

Background

Previous cross-temporal meta-analyses have demonstrated that anxiety would get severer over time. The changes of anxiety in Chinese military personnels over time remain unclear.

Aim

To explore the changes of anxiety in Chinese military personnels over nearly past two decades.

Methods

Studies using the Chinese version of Spielberger’s State-Trait Anxiety Inventory (STAI) in Chinese serviceman on active duty were primarily collected. Mean, standard deviation and sample size of each study were extracted for meta-analysis. With sample size of each study as weighted least-squares weight, we regressed the mean scores on the data collection year to evaluate changes in anxiety from 1991 to 2011. Correlations between the anxiety scores and some social indicators were also examined.

Results

The final sample consisted of 45 separate studies with a total of 18,106 participants for state anxiety and 21,047 participants for trait anxiety. Both state anxiety and trait anxiety significantly increased over the past two decades. The effect sizes for state anxiety and trait anxiety were 0.88 and 0.63, respectively. Anxiety scores were significantly correlated with some social indicators (e.g., crime rate, unemployment rate) of the corresponding years or 5 years prior to the anxiety data collection.

Conclusions

Some measures must be taken to tackle the problem of the rising anxiety scores. Given that Chinese military personnels are continuing to experience high levels of anxiety, it is crucial to consider the implications for mental health care and treatment. More cross-temporal meta-analyses are needed to examine the changes of mental health in Chinese military personnels over time.

COGNITIVE ABILITY OF PRESCHOOL, PRIMARY AND SECONDARY SCHOOL CHILDREN IN COSTA RICA

Cognitive abilities of children in Costa Rica and Austria were compared using three age groups (N=385/366). Cognitive ability tests (mental speed, culture reduced/fluid intelligence, literacy/crystallized intelligence) were applied that differed in the extent to which they refer to school-related knowledge. Preschool children (kindergarten, 5–6 years old,NCR=80,NAu=51) were assessed with the Coloured Progressive Matrices (CPM), primary school children (4th grade, 9–11 years old,NCR=71,NAu=71) with ZVT (a trail-making test), Standard Progressive Matrices (SPM) and items from PIRLS-Reading and TIMSS-Mathematics, and secondary school students (15–16 years old,NCR=48,NAu=48) with ZVT, Advanced Progressive Matrices (APM) and items from PISA-Reading and PISA-Mathematics. Additionally, parents and pupils were given questionnaires covering family characteristics and instruction. Average cognitive abilities were higher in Austria (Greenwich-IQMCR=87 andMAu=99,dIQ=12 points) and differences were smaller in preschool than in secondary school (dIQ=7 vs 20 points). Differences in crystallized intelligence were larger than in fluid intelligence (mental speed:dIQ=12, Raven:dIQ=10, student achievement tests:dIQ=17 IQ points). Differences were larger in comparisons at the level ofg-factors. Austrian children were also taller (6.80 cm,d=1.07 SD), but had lower body mass index (BMICR=19.35 vs BMIAu=17.59,d=−0.89 SD). Different causal hypotheses explaining these differences are compared.

Leveling the playing field: attention mitigates the effects of intelligence on memory

Effective attention and memory skills are fundamental to typical development and essential for achievement during the formal education years. It is critical to identify the specific mechanisms linking efficiency of attentional selection of an item and the quality of its memory retention. The present study capitalized on the spatial cueing paradigm to examine the role of selection via suppression in modulating children and adolescents' memory encoding. By varying a single parameter, the spatial cueing task can elicit either a simple orienting mechanism (i.e., facilitation) or one that involves both target selection and simultaneous suppression of competing information (i.e., IOR). We modified this paradigm to include images of common items in target locations. Participants were not instructed to learn the items and were not told they would be completing a memory test later. Following the cueing task, we imposed a 7-min delay and then asked participants to complete a recognition memory test. Results indicated that selection via suppression promoted recognition memory among 7-17year-olds. Moreover, individual differences in the extent of suppression during encoding predicted recognition memory accuracy. When basic cueing facilitated orienting to target items during encoding, IQ was the best predictor of recognition memory performance for the attended items. In contrast, engaging suppression (i.e., IOR) during encoding counteracted individual differences in intelligence, effectively improving recognition memory performance among children with lower IQs. This work demonstrates that engaging selection via suppression during learning and encoding improves memory retention and has broad implications for developing effective educational techniques.

Girl in the cellar: a repeated cross-sectional investigation of belief in conspiracy theories about the kidnapping of Natascha Kampusch

The present study utilized a repeated cross-sectional survey design to examine belief in conspiracy theories about the abduction of Natascha Kampusch. At two time points (October 2009 and October 2011), participants drawn from independent cross-sections of the Austrian population (Time Point 1, N = 281; Time Point 2, N = 277) completed a novel measure of belief in conspiracy theories concerning the abduction of Kampusch, as well as measures of general conspiracist ideation, self-esteem, paranormal and superstitious beliefs, cognitive ability, and media exposure to the Kampusch case. Results indicated that although belief in the Kampusch conspiracy theory declined between testing periods, the effect size of the difference was small. In addition, belief in the Kampusch conspiracy theory was significantly predicted by general conspiracist ideation at both time points. The need to conduct further longitudinal tests of conspiracist ideation is emphasized in conclusion.

The Increase in Colored Progressive Matrices Test Performance in Individuals With Down Syndrome: A Qualitative and Quantitative Review

It is well known that a normal population improves its IQ test scores by about 3 points per decade. This is called the Flynn effect and has been explained in different and sometimes contrasting ways. Few and ambiguous data are available on any Flynn effect in individuals with an atypical development, such as those with intellectual disabilities: some studies report evidence of the Flynn effect, whereas others do not. The main objective of the present study was to analyze the performance of individuals with Down syndrome (DS) compared with a sample of typically developing (TD) children in the Colored Progressive Matrices (CPM) test, which measures abstract reasoning and is commonly used to estimate IQ, to see whether a Flynn effect is present. Our results suggest that the Flynn effect in the DS population depends on the individual’s age.