Construct Validity, Longitudinal Measurement Invariance, Incremental Validity, and Predictive Validity of the Original Grit Scale in Chinese Young Adults.

Although many studies have attempted to validate grit scales because of the construct's popularity, most have considered the shorter rather than the longer Original Grit Scale (Grit-O). We examined the Grit-O's construct validity, longitudinal measurement invariance, incremental validity for academic performance, and longitudinal predictive validity for subjective well-being among young Chinese. We used a cross-sectional sample of 3,322 college students and a longitudinal sample of 1,884 college students, tested twice over 10 months. The first-order factor model fit the data better than other models and showed partial configural and metric measurement invariance over time. Grit and its two facets longitudinally predicted subjective well-being (i.e., life satisfaction, happiness, positive affect, negative affect, and depression) but had negligible incremental validity for two semesters' grades after controlling for conscientiousness. So, while the Grit-O could be a useful construct for young adults, its predictive value overlaps with a better-established construct, conscientiousness.

Body mass predicts personality development across 18 years in middle to older adulthood.

OBJECTIVE: Various personality traits have longitudinal relations with body mass index (BMI), a measure of body weight and a risk factor for numerous health concerns. We tested these associations' compatibility with causality in either direction. METHOD: Using three waves of the Wisconsin Longitudinal Study (N = 12,235, Mage  = 53.33 at baseline), we tested how accurately the Five-Factor Model personality domains and their items could collectively predict BMI and change in it with elastic net models. With multilevel models, we tested (a) bidirectional and (b) within-person associations between BMI and personality traits. RESULTS: The five domains were able to predict concurrent (r = 0.08), but not future BMI. Twenty-nine personality items predicted concurrent and future BMI at r = 0.21 and r = 0.16 to 0.25, respectively. Neither the domains nor items could collectively predict change in BMI. Similarly, no individual trait predicted change in BMI, but BMI predicted changes in Conscientiousness, Agreeableness, and several items (|b*| = 0.03 to 0.08). BMI had within-person correlations with these same traits; time-invariant third factors like genetics or childhood environments therefore could not (fully) account for their relations. CONCLUSIONS: Body weight may contribute to adults' personality development, but the reverse appears less likely.

Social expectations as a possible mechanism for adult personality change: Limited empirical evidence for the social investment principle.

OBJECTIVE: Personality traits change in both mean levels and variance across the life span but the mechanisms underlying these developmental trends remain unclear. Social Investment Principle (SIP) suggests that social expectations drive personality changes in adulthood. Accordingly, we tested whether differences between personality traits in social expectations for them can explain their different change trajectories in young adulthood. METHODS: A pool of 257 personality items was used to measure personality traits' means and variances (N = 1096), and levels expected by friends, partners and bosses/supervisors (N = 121). RESULTS: Raters were consistent in their expectations for how young adults should think, feel and behave. Traits under stronger expectations had higher mean levels and lower variances than traits under lower expectations; trait means and variances increased with age, but inconsistently with the SIP, these increases were unrelated to the traits' expected levels. CONCLUSION: Our results are only partially consistent with the SIP.

Social expectations and abilities to meet them as possible mechanisms of youth personality development.

OBJECTIVE: Personality traits change from childhood through late-adolescence, however the effects of social expectations and self-regulatory efforts remain unknown. This study aims to explore mechanisms underlying personality development by assessing mean levels personality traits from childhood to late-adolescence. METHOD: We used Common-Language California Child Q-Set to measure youths' (N = 11,000) mean personality trait levels; social expectations for these traits as perceived by parents (N = 47), teachers (N = 42) and students (N = 120); and self-regulatory efforts required for achieving the desired levels in these traits as perceived by parents (N = 27), teachers (N = 26), and students (N = 54). RESULTS: Expectations for youths' traits were consistent, regardless of raters' or youths' age. In our unique between-trait study design, traits' mean levels were positively associated with expectations for them, but age differences minimally tracked these expectations. Traits' required self-regulatory efforts were not associated with their developmental trends. CONCLUSIONS: Results were only partially consistent with existing developmental theories of personality development.

Test-Retest Reliability and Construct Validity of the Brief Dark Triad Measurements.

Despite the widespread use of the Dirty Dozen (DD) and Short Dark Triad (SD3) as inventories for antagonist personality constructs, appropriately powered studies on their test-retest reliability (rtt) are lacking. We report the 12-day rtt-s of the DD and SD3 scales. Leveraging the test-retest data, we also calculated their convergent and discriminant correlations while controlling for measurement error. Median rtt-s were .87 and .90 (N = 500) for the DD and SD3 scales, respectively, substantially higher than their internal consistencies. Convergent correlations were .77, .63 and .64 for Machiavellianism, Narcissism and Psychopathy, respectively. Discriminant correlations between the Machiavellianism and Psychopathy scales had a median of .65, pointing to their being effectively indistinguishable traits in the SD3 and DD. The DD and SD3 items had median rtt-s of .69 and .71, respectively. We emphasize the importance of the rtt for scale development and validation.

The finer details? The predictability of life outcomes from Big Five domains, facets, and nuances.

Associations between personality traits and life outcomes are usually studied using the Big Five domains and, occasionally, their facets. But recent research suggests these associations may be driven by the items (reflecting personality nuances) chosen to measure these traits. Using a large dataset (N = 6126), we examined associations with 53 self-reported outcomes using domains, facets and items (markers for nuances), training and validating models in different sample partitions. Facets better predicted outcomes than domains (on average, 18.0% versus 16.6% of variance explained), but items provided the most accurate predictions (on average 20.9%). Removing domain and facet variance from items had no effect on their predictive validity, suggesting that outcome-related information was often in items' unique variances (i.e., nuance-specific). Item-based prediction also showed the highest discriminant validity. These observations, replicating previous findings, suggest that personality traits' valid associations with outcomes are often driven by narrow personality nuances.

Two genetic analyses to elucidate causality between body mass index and personality.

BACKGROUND/OBJECTIVES: Many personality traits correlate with BMI, but the existence and direction of causal links between them are unclear. If personality influences BMI, knowing this causal direction could inform weight management strategies. Knowing that BMI instead influences personality would contribute to a better understanding of the mechanisms of personality development and the possible psychological effects of weight change. We tested the existence and direction of causal links between BMI and personality. SUBJECTS/METHODS: We employed two genetically informed methods. In Mendelian randomization, allele scores were calculated to summarize genetic propensity for the personality traits neuroticism, worry, and depressive affect and used to predict BMI in an independent sample (N = 3 541). Similarly, an allele score for BMI was used to predict eating-specific and domain-general phenotypic personality scores (PPSs; aggregate scores of personality traits weighted by BMI). In a direction of causation (DoC) analysis, twin data from five countries (N = 5424) were used to assess the fit of four alternative models: PPSs influencing BMI, BMI influencing PPSs, reciprocal causation, and no causation. RESULTS: In Mendelian randomization, the allele score for BMI predicted domain-general (ß = 0.05; 95% CI: 0.02, 0.08; P = 0.003) and eating-specific PPS (ß = 0.06; 95% CI: 0.03, 0.09; P < 0.001). The allele score for worry also predicted BMI (ß = -0.05; 95% CI: -0.08, -0.02; P < 0.001), while those for neuroticism and depressive affect did not (P ≥ 0.459). In DoC, BMI similarly predicted domain-general (ß = 0.21; 95% CI:, 0.18, 0.24; P < 0.001) and eating-specific personality traits (ß = 0.19; 95% CI:, 0.16, 0.22; P < 0.001), suggesting causality from BMI to personality traits. In exploratory analyses, links between BMI and domain-general personality traits appeared reciprocal for higher-weight individuals (BMI > ~25). CONCLUSIONS: Although both genetic analyses suggested an influence of BMI on personality traits, it is not yet known if weight management interventions could influence personality. Personality traits may influence BMI in turn, but effects in this direction appeared weaker.

Big Five facets' associations with pro-environmental attitudes and behaviors.

Climate change mandates us to understand why individuals do (not) behave pro-environmentally and personality traits are well suited for this purpose. Past research has mostly focused on how broad domain-level personality traits were associated with pro-environmental attitudes and behaviors. In two datasets (N = 501 and 287), we examined whether personality facets provided a more detailed picture of how personality traits were associated with pro-environmental attitudes and behaviors. It was found that some facets were the main drivers of domain-level associations. Furthermore, it was found that facets, collectively, predicted pro-environmental attitudes (r = .50 to .52) and behaviors (r = .29 to .42) in holdout datasets. This predictive ability was on par with the predictive ability of domains. Therefore, facets provided a greater understanding of how personality traits were associated with pro-environmental attitudes and behaviors. Furthermore, facets provided a similar predictive ability of pro-environmental attitudes and behaviors to that of domains.

Source method biases as implicit personality theory at the domain and facet levels.

OBJECTIVE: We tested predictions about the structure and magnitude of method biases in single-source personality trait assessments. We expected a large number of distinct biases that would parallel the observed structure of traits, at both facet and item levels. METHOD: We analyzed multimethod ratings on the Estonian NEO Personality Inventory-3 in a sample of 3,214 adults. By subtracting informant ratings from self-reports, we eliminated true score variance and analyzed the size and structure of the residual method biases. We replicated analyses using data (N = 709) from the Czech Revised NEO Personality Inventory. RESULTS: The magnitude of method biases was consistent with predictions by McCrae (2018, Psychological Assessment). Factor analyses at the facet level showed a clear replication of the normative Five-Factor Model structure in both samples. Item factor analyses within domains showed that facet-level method biases mimicked the facet structure of the instrument. CONCLUSIONS: Method biases apparently reflect implicit personality theory (IPT)-beliefs about how traits and trait indicators covary. We discuss the (collective) accuracy and possible origins of IPT. Because method biases limit the accuracy of single-source assessments, we recommend assessments that combine information from two or more informants.

Intelligence as a predictor of social mobility in Estonia.

The purpose of this study was to explore how individual and environmental predictors of intergenerational social mobility intersect in rarely studied post-communist developing society of Estonia. We used a contemporary cross-sectional dataset (n = 759) to assess the influence of cognitive ability and parental socioeconomic status to the participants' educational and occupational attainment. Our results indicated that cognitive ability and one's own educational level mediated the association of parental socioeconomic status with one's own occupational success. Analysis of separate components of cognitive ability indicated that verbal ability had the highest influence on occupational status. We concluded that both individual-level and environmental factors have a predictive effect on educational and occupational attainment.

The Gaussian Graphical Model in Cross-Sectional and Time-Series Data.

We discuss the Gaussian graphical model (GGM; an undirected network of partial correlation coefficients) and detail its utility as an exploratory data analysis tool. The GGM shows which variables predict one-another, allows for sparse modeling of covariance structures, and may highlight potential causal relationships between observed variables. We describe the utility in three kinds of psychological data sets: data sets in which consecutive cases are assumed independent (e.g., cross-sectional data), temporally ordered data sets (e.g., n = 1 time series), and a mixture of the 2 (e.g., n > 1 time series). In time-series analysis, the GGM can be used to model the residual structure of a vector-autoregression analysis (VAR), also termed graphical VAR. Two network models can then be obtained: a temporal network and a contemporaneous network. When analyzing data from multiple subjects, a GGM can also be formed on the covariance structure of stationary means-the between-subjects network. We discuss the interpretation of these models and propose estimation methods to obtain these networks, which we implement in the R packages graphicalVAR and mlVAR. The methods are showcased in two empirical examples, and simulation studies on these methods are included in the supplementary materials.

Educational Attainment and Personality Are Genetically Intertwined.

Heritable variance in psychological traits may reflect genetic and biological processes that are not necessarily specific to these particular traits but pertain to a broader range of phenotypes. We tested the possibility that the personality domains of the five-factor model and their 30 facets, as rated by people themselves and their knowledgeable informants, reflect polygenic influences that have been previously associated with educational attainment. In a sample of more than 3,000 adult Estonians, education polygenic scores (EPSs), which are interpretable as estimates of molecular-genetic propensity for education, were correlated with various personality traits, particularly from the neuroticism and openness domains. The correlations of personality traits with phenotypic educational attainment closely mirrored their correlations with EPS. Moreover, EPS predicted an aggregate personality trait tailored to capture the maximum amount of variance in educational attainment almost as strongly as it predicted the attainment itself. We discuss possible interpretations and implications of these findings.

Personality and Risk of Frailty: the English Longitudinal Study of Ageing.

BACKGROUND: There is evidence that the personality traits conscientiousness, extraversion and neuroticism are associated with health behaviours and with risk of various health outcomes. We hypothesised that people who are lower in conscientiousness or extraversion or higher in neuroticism may be at greater risk of frailty in later life. METHODS: We used general linear models to examine the prospective relation between personality, assessed using the Midlife Development Inventory, and change in frailty, modelled by a frailty index, in 5314 men and women aged 60 to over 90 years from the English Longitudinal Study of Ageing. RESULTS: Men and women with higher levels of neuroticism or lower levels of extraversion or conscientiousness had an increased frailty index score at follow-up. After adjustment for potential confounding or mediating variables, including frailty index score at baseline, the frailty index score at follow-up-which potentially ranges from 0 to 1-was higher by 0.035 (95 % confidence interval 0.018, 0.052) for a standard deviation increase in neuroticism and lower by 0.061 (0.031, 0.091) or 0.045 (0.020, 0.071) for a standard deviation increase in extraversion or conscientiousness, respectively. There was some evidence that the association between extraversion and frailty may be due to reverse causation whereby poorer health affected responses to items in the personality inventory. CONCLUSIONS: Higher levels of neuroticism or lower levels of conscientiousness or extraversion may be risk factors for the onset or progression of frailty. Future studies need to replicate these observations in other populations and explore the mechanisms underlying these associations.

Markers of Psychological Differences and Social and Health Inequalities: Possible Genetic and Phenotypic Overlaps.

Associations between markers of ostensible psychological characteristics and social and health inequalities are pervasive but difficult to explain. In some cases, there may be causal influence flowing from social and health inequalities to psychological differences, whereas sometimes it may be the other way around. Here, we focus on the possibility that some markers that we often consider as indexing different domains of individual differences may in fact reflect at least partially overlapping genetic and/or phenotypic bases. For example, individual differences in cognitive abilities and educational attainment appear to reflect largely overlapping genetic influences, whereas cognitive abilities and health literacy may be almost identical phenomena at the phenotypic, never mind genetic, level. We make the case for employing molecular genetic data and quantitative genetic techniques to better understand the associations of psychological individual differences with social and health inequalities. We illustrate these arguments by using published findings from the Lothian Birth Cohort and the Generation Scotland studies. We also present novel findings pertaining to longitudinal stability and change in older age personality traits and some correlates of the change, molecular genetic data-based heritability estimates of Neuroticism and Extraversion, and the genetic correlations of these personality traits with markers of social and health inequalities.

SNP-Based Heritability Estimates of Common and Specific Variance in Self- and Informant-Reported Neuroticism Scales.

OBJECTIVE: Our study aims to estimate the proportion of the phenotypic variance of Neuroticism and its facet scales that can be attributed to common single-nucleotide polymorphisms (SNPs) in two adult populations from Estonia (EGCUT; N = 3,292) and the Netherlands (Lifelines; N = 13,383). METHOD: Genomic-relatedness-matrix restricted maximum likelihood (GREML) using genome-wide complex trait analysis (GCTA) software was employed. To build upon previous research, we used self- and informant reports of the 30-facet NEO personality inventories and analyzed both the usual sum scores and the residual facet scores of Neuroticism. RESULTS: In the EGCUT cohort, the proportion of phenotypic variance explained by the additive effects of common genetic variants in self- and informant-reported Neuroticism domain scores was 15.2% (p = .070, SE = .11) and 6.2% (p = .293, SE = .12), respectively. The SNP-based heritability estimates at the level of Neuroticism facet scales differed greatly across cohorts and modes of measurement but were generally higher (a) for self- than for informant reports, and (b) for sum than for residual scores. CONCLUSIONS: Our findings indicate that a large proportion of the heritability of Neuroticism is not captured by additive genetic effects of common SNPs, with some evidence for Gene × Environment interaction across cohorts.

A bottom-up approach dramatically increases the predictability of body mass from personality traits.

Personality traits consistently relate to and allow predicting body mass index (BMI), but these associations may not be adequately captured with existing inventories' domains or facets. Here, we aimed to test the limits of how accurately BMI can be predicted from and described with personality traits. We used three large datasets (combined N ≈ 100,000) with nearly 700 personality assessment items to (a) empirically identify clusters of personality traits linked to BMI and (b) identify relatively small sets of items that predict BMI as accurately as possible. Factor analysis revealed 14 trait clusters showing well-established personality trait-BMI associations (disorganization, anger) and lesser-known or novel ones (altruism, obedience). Most of items' predictive accuracy (up to r = .24 here but plausibly much higher) was captured by relatively few items. Brief scales that predict BMI have potential clinical applications-for instance, screening for risk of excessive weight gain or related complications.

Most people's life satisfaction matches their personality traits: True correlations in multitrait, multirater, multisample data.

Despite numerous meta-analyses, the true extent to which life satisfaction reflects personality traits has remained unclear due to overreliance on a single method to assess both and insufficient attention to construct overlaps. Using data from three samples tested in different languages (Estonian, N = 20,886; Russian, N = 768; English, N = 600), we combined self- and informant-reports to estimate personality domains' and nuances' true correlations (rtrue) with general life satisfaction (LS) and satisfactions with eight life domains (DSs), while controlling for single-method and occasion-specific biases and random error, and avoiding direct construct overlaps. The associations replicated well across samples. The Big Five domains and nuances allowed predicting LS with accuracies up to rtrue ≈ .80-.90 in independent (sub)samples. Emotional stability, extraversion, and conscientiousness correlated rtrue ≈ .30-.50 with LS, while its correlations with openness and agreeableness were small. At the nuances level, low LS was most strongly associated with feeling misunderstood, unexcited, indecisive, envious, bored, used, unable, and unrewarded (rtrue ≈ .40-.70). Supporting LS's construct validity, DSs had similar personality correlates among themselves and with LS, and an aggregated DS correlated rtrue ≈ .90 with LS. LS's approximately 10-year stability was rtrue = .70 and its longitudinal associations with personality traits mirrored cross-sectional ones. We conclude that without common measurement limitations, most people's life satisfaction is highly consistent with their personality traits, even across many years. So, satisfaction is usually shaped by these same relatively stable factors that shape personality traits more broadly. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Self- and informant-reported personality traits and vaccination against COVID-19.

As COVID-19 vaccines' accessibility has grown, so has the role of personal choice in vaccination, and not everybody is willing to vaccinate. Exploring personality traits' associations with vaccination could highlight some person-level drivers of, and barriers to, vaccination. We used self- and informant-ratings of the Five-Factor Model domains and their subtraits (a) measured approximately at the time of vaccination with the 100 Nuances of Personality (100NP) item pool (N = 56,575) and (b) measured on average ten years before the pandemic with the NEO Personality Inventory-3 (NEO-PI-3; N = 3,168). We tested individual domains' and either items' (in the 100NP sample) or facets' (in the NEO-PI-3 sample) associations with vaccination, as well as their collective ability to predict vaccination using elastic net models trained and tested in independent sample partitions. Although the NEO-PI-3 domains and facets did not predict vaccination ten years later, the domains correlated with vaccination in the 100NP sample, with vaccinated people scoring slightly higher on neuroticism and agreeableness and lower on openness, controlling for age, sex, and education. Collectively, the five domains predicted vaccination with an accuracy of r = .08. Associations were stronger at the item level. Vaccinated people were, on average, more science-minded, politically liberal, respectful of rules and authority, and anxious but less spiritual, religious, and self-assured. The 100NP items collectively predicted vaccination with r = .31 accuracy. We conclude that unvaccinated people may be a psychologically heterogeneous group and highlight some potential areas for action in vaccination campaigns.

Personality nuances and risk of dementia: Evidence from two longitudinal studies.

Personality traits are broad constructs composed of nuances, operationalized by personality items, that can provide a more granular understanding of personality associations with health outcomes. This study examined the associations between personality nuances and incident dementia and evaluated whether nuances associations replicate across two samples. Health and Retirement Study (HRS, N = 11,400) participants were assessed in 2006/2008, and the English Longitudinal Study of Ageing (ELSA, N = 7453) participants were assessed in 2010/2011 on personality and covariates. Dementia incidence was tracked for 14 years in the HRS and 8 years in ELSA. In both HRS and ELSA, higher neuroticism domain and nuances (particularly nervous and worry) were related to a higher risk of incident dementia, whereas higher conscientiousness domain and nuances (particularly responsibility and organization) were associated with a lower risk of dementia. To a lesser extent, higher extraversion (active), openness (broad-minded, curious, and imaginative), and agreeableness (helpful, warm, caring, and sympathetic) nuances were associated with a lower risk of dementia, with replicable effects across the two samples. A poly-nuance score, aggregating the effects of personality items, was associated with an increased risk of incident dementia in the HRS and ELSA, with effect sizes slightly stronger than those of the personality domains. Clinical, behavioral, psychological, and genetic covariates partially accounted for these associations. The present study provides novel and replicable evidence for specific personality characteristics associated with the risk of incident dementia.

Nuanced HEXACO: A Meta-Analysis of HEXACO Cross-Rater Agreement, Heritability, and Rank-Order Stability.

Most Five-Factor Model (FFM) questionnaire items contain unique variance that is partly heritable, stable, and consensually observable, demonstrates consistent associations with age and sex, and predicts life outcomes beyond higher order factors. Extending these findings to the HEXACO model, we meta-analyzed single-item cross-rater agreement, heritability, and 2-year stability using samples from six countries. We analyzed raw item scores and their residual variance and adjusted the estimates for measurement unreliability. The median cross-rater agreement, heritability, and stability estimates were, respectively, .30, .30, and .57, for raw items and .10, .16, and .39, for item residuals. Adjusted for reliability, the respective medians were .46 and .25 for cross-rater agreement, .46 and .39 for heritability, and .87 and .94 for stability. These results are strikingly consistent with FFM-based findings, providing nondismissible evidence that single items index a partly unique level of the trait hierarchy-personality nuances-with trait properties comparable to those of higher-order traits.