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The history of the British Isles and Ireland is characterized by multiple periods of major cultural change, including the influential transformation after the end of Roman rule, which precipitated shifts in language, settlement patterns and material culture1. The extent to which migration from continental Europe mediated these transitions is a matter of long-standing debate2–4. Here we study genome-wide ancient DNA from 460 medieval northwestern Europeans—including 278 individuals from England—alongside archaeological data, to infer contemporary population dynamics. We identify a substantial increase of continental northern European ancestry in early medieval England, which is closely related to the early medieval and present-day inhabitants of Germany and Denmark, implying large-scale substantial migration across the North Sea into Britain during the Early Middle Ages. As a result, the individuals who we analysed from eastern England derived up to 76% of their ancestry from the continental North Sea zone, albeit with substantial regional variation and heterogeneity within sites. We show that women with immigrant ancestry were more often furnished with grave goods than women with local ancestry, whereas men with weapons were as likely not to be of immigrant ancestry. A comparison with present-day Britain indicates that subsequent demographic events reduced the fraction of continental northern European ancestry while introducing further ancestry components into the English gene pool, including substantial southwestern European ancestry most closely related to that seen in Iron Age France

As the world navigates unchartered territories and witnesses the overwhelming impact of COVID-19, investigators face important challenges to ensure continuity of research studies in a scientifically sound manner. Given the susceptibility of the older population to COVID-19, research in the field of ageing and dementia may be more severely impacted than other areas. With in-person testing halted, researchers are considering remote testing to collect data on questionnaires and functioning, including cognitive functioning. This is not without challenges. Here, we discuss psychometric properties of the scales that need to be considered and evaluated when implementing remote testing to ensure the quality of the studies is preserved. We encourage the community to join efforts to improve practice sharing and facilitating access to item level data.

Despite the widespread use of the HEXACO model as a descriptive taxonomy of personality traits, there remains limited information on the test-retest reliability of commonly-used inventories to measure its traits. Studies typically report internal consistency estimates, such as alpha or omega, as measures of reliability, but there are good reasons to believe that these do not accurately assess reliability. Therefore, we report 12-day test-retest correlations of the 100- and 60-item English HEXACO-Personality Inventory-Revised (HEXACO-100 and HEXACO-60) domains, facets, and items. In order to test the validity of test-retest reliability, we then compare these estimates to correlations between self- and informant- reports (also known as cross-rater agreement), a widely-used validity criterion, as well as to domain and facet internal consistencies. Median estimates of test-retest reliability were .88, .81, and .65 (N = 416) for domains, facets, and items, respectively. Facets' and items' test-retest reliabilities were highly correlated with their cross-rater agreement estimates, whereas alphas were not. Overall, the HEXACO-Personality Inventory-Revised demonstrates test-retest reliability similar to other contemporary measures. We recommend that short-term retest reliability should be routinely calculated to assess reliability.

The International Personality Item Pool (IPIP) five-factor model inventories are widely used for personality research and have been translated into multiple languages. However, the extent of the psychometric assessment of translated scales is variable, often minimal. The lack of psychometric scrutiny is particularly problematic because translation is an inherently complex process. Here, we present a structural analysis of one Spanish translation of the 50-item IPIP five-factor inventory in a sample of Peruvian, non-university educated, working adults (n = 778). A global confirmatory factor analytic (CFA) model of the a priori five factors failed to fit. So too did single factor models for four of the five factors, the exception being Neuroticism. Fit was improved via use of an exploratory structural equation measurement model, but the resultant solution showed very poor theoretical coherence. So, we explored the data for systematic measurement artefacts and sought to model them to improve the psychometric properties of the scale. Specifically, the pattern of factor loadings suggested that the lack of coherence might be due to the effects of the valence of item wording (i.e., positively or negatively worded items). CFA models including five substantive factors and a series of method factors modelling shared covariance based on item wording, improved fit and coherence. This investigation suggests that unless method factors are explicitly modelled the tested Spanish translation may not be suitable for use in certain Spanish-speaking countries or samples composed of non-university educated participants. More broadly, the study has implications for many translated scales, especially when used without thorough psychometric evaluation.

School-based psychosocial interventions are a widely used approach to preventing or reducing externalising behaviour. However, evaluating the effects of such interventions is complicated by the fact that the interventions may not only change the target behaviour, but also the way that informants report on that behaviour. For example, teachers may become more aware of bullying behaviour after delivering lessons on the topic, resulting in increased teacher reports of the behaviour. In this study, we used multi-group confirmatory factor analysis to evaluate whether teachers exposed to the Promoting Alternative Thinking Strategies (PATHS) intervention changed the way they reported on child externalising behaviour. Using data from the z-proso study (802 participants; 51% male; 69 teachers), teacher reports of aggressive behaviour, attention deficit hyperactivity disorder, and non-aggressive conduct disorder symptoms were compared pre- and post- intervention and across the intervention and control conditions. There was no evidence that teacher reporting was affected by exposure to the intervention. This helps bolster the interpretation of intervention effects as reflecting changes in child behaviour, rather than in the manner of informant reporting.

Objective: Sex differences in personality are a matter of continuing debate. In a study on the US standardization sample of Cattell’s 16PF (fifth edition), Del Giudice and colleagues (2012; PLoS ONE, 7, e29265) estimated global sex differences in personality with multigroup covariance and mean structure analysis (MG-CMSA). The study found a surprisingly large multivariate effect, D = 2.71. Here we replicated the original analysis with an open online dataset employing an equivalent version of the 16PF. Method: We closely replicated the original MG-MCSA analysis on N = 21,567 US participants (63% females, age 16-90); for robustness, we also analyzed N = 31,637 participants across English-speaking countries (61% females, age 16-90). Results: The size of global sex differences was D = 2.06 in the US and D = 2.10 across English speaking countries. Parcel-allocation variability analysis showed that results were robust to changes in parceling (US: median D = 2.09, IQR [1.89, 2.37]; English-speaking countries: median D = 2.17, IQR [1.98, 2.47]). Conclusions: Our results corroborate the original study (with a comparable if somewhat smaller effect size) and provide new information on the impact of parcel allocation. We discuss the implications of these and similar findings for the psychology of sex differences.

Objective Mean speed of responding is the most commonly used measure in the assessment of reaction time (RT). An alternative measure is intraindividual variability (IIV): the inconsistency of responding across multiple trials of a test. IIV has been suggested as an important indicator of central nervous system functioning, and as such, there has been increasing interest in the associations between IIV and brain imaging metrics. Results however, have been inconsistent. The present seeks to provide a comprehensive evaluation of the associations between a variety of measures of brain white matter integrity and individual differences in choice RT (CRT) IIV. Method MRI brain scans of members of the Lothian Birth Cohort 1936 were assessed to obtain measures of the volume and severity of white matter hyperintensities, and the integrity of brain white matter tracts. CRT was assessed with a 4 CRT task on a separate occasion. Data were analyzed using multiple regression (N range = 358-670). Results Greater volume of hyperintensities and more severe hyperintensities in frontal regions were associated with higher CRT IIV. White matter tract integrity, as assessed by both fractional anisotropy and mean diffusivity, showed the smallest effect sizes in associations with CRT IIV. Associations with hyperintensities were attenuated and no longer significant after controlling for M CRT. Conclusions Taken together, the results of the present study suggested that IIV was not incrementally predictive of white matter integrity over mean speed. This is in contrast to previous reports, and highlights the need for further study. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Background: Previous studies have hinted at sex differences in developmental trajectories in ADHD symptoms; however, little is known about the nature or cause of these differences and their implications for clinical practice.Method: We used growth mixture modelling in a community-ascertained cohort of n=1571 participants to study sex differences in ADHD symptom developmental trajectories across the elementary and secondary school years. Participants were measured at ages 7, 8, 9, 10, 11, 12, 13, and 15.Results: We found that females were more likely to show large symptom increases in early adolescence while males were more likely to show elevated symptoms from childhood. For both males and females, early adolescence represented a period of vulnerability characterised by relatively sudden symptom increases. Conclusions: Females affected by hyperactivity/impulsivity may be more likely to be excluded from diagnosis due to current age of onset criteria. More attention should be paid to early adolescence as a period of risk for hyperactivity/impulsivity symptom onset or worsening.

Establishing the neural bases of individual differences in personality has been an enduring topic of interest. However, while a growing literature has sought to characterise grey matter correlates of personality traits, little attention to date has been focused on regional white matter correlates of personality, especially for the personality traits agreeableness, conscientiousness, and openness. To rectify this gap in knowledge we used a large sample (n>550) of older adults who provided data on both personality (International Personality Item Pool: IPIP) and white matter tract-specific fractional anisotropy (FA) from diffusion tensor MRI. Results indicated that conscientiousness was associated with greater FA in the left uncinate fasciculus (β = .17, p < .001). We also examined links between FA and the personality meta-trait ‘stability’, which is defined as the common variance underlying agreeableness, conscientiousness, and neuroticism/emotional stability. We observed an association between left uncinate fasciculus FA and stability (β = .27, p

When self-report items with a Likert-type scale include a middle response option (e.g., Unsure, Neither agree nor disagree, or ?), this middle option is assumed to measure a level of the trait intermediate between the high and low response categories. In this study, we tested this assumption in the 16 Personality Factor Questionnaire, Version 5 (16PF5) by fitting Bock's nominal response model in the U.S. and UK standardization samples of the 16PF5. We found that in many cases, the middle option was indicative of higher levels of the latent trait than the ostensibly highest response option. In certain other cases, it was indicative of lower levels of the latent trait than the ostensibly lowest response option. This undermines the use of a simple successive integer scoring scheme where responses in adjacent response categories are assigned scores of 0, 1, and 2. Recommendations for alternative scoring schemes are provided. Results also suggested that certain personality traits, especially neurotic traits, are associated with a tendency toward selecting the middle option.

Highlights • We assessed Perivascular Spaces (PVS) computationally in the centrum semiovale. • We measured total PVS volume and count, and individual PVS length, width, size. • Computational PVS measures correlated positively with PVS ratings. • PVS were associated with hypertension stroke and white matter hyperintensities., Background and Purpose Perivascular Spaces (PVS), also known as Virchow-Robin spaces, seen on structural brain MRI, are important fluid drainage conduits and are associated with small vessel disease (SVD). Computational quantification of visible PVS may enable efficient analyses in large datasets and increase sensitivity to detect associations with brain disorders. We assessed the associations of computationally-derived PVS parameters with vascular factors and white matter hyperintensities (WMH), a marker of SVD. Participants Community dwelling individuals (n = 700) from the Lothian Birth Cohort 1936 who had multimodal brain MRI at age 72.6 years (SD = 0.7). Methods We assessed PVS computationally in the centrum semiovale and deep corona radiata on T2-weighted images. The computationally calculated measures were the total PVS volume and count per subject, and the mean individual PVS length, width and size, per subject. We assessed WMH by volume and visual Fazekas scores. We compared PVS visual rating to PVS computational metrics, and tested associations between each PVS measure and vascular risk factors (hypertension, diabetes, cholesterol), vascular history (cardiovascular disease and stroke), and WMH burden, using generalized linear models, which we compared using coefficients, confidence intervals and model fit. Results In 533 subjects, the computational PVS measures correlated positively with visual PVS ratings (PVS count r = 0.59; PVS volume r = 0.61; PVS mean length r = 0.55; PVS mean width r = 0.52; PVS mean size r = 0.47). PVS size and width were associated with hypertension (OR 1.22, 95% CI [1.03 to 1.46] and 1.20, 95% CI [1.01 to 1.43], respectively), and stroke (OR 1.34, 95% CI [1.08 to 1.65] and 1.36, 95% CI [1.08 to 1.71], respectively). We found no association between other PVS measures and diabetes, hypercholesterolemia or cardiovascular disease history. Computational PVS volume, length, width and size were more strongly associated with WMH (PVS mean size versus WMH Fazekas score β = 0.66, 95% CI [0.59 to 0.74] and versus WMH volume β = 0.43, 95% CI [0.38 to 0.48]) than computational PVS count (WMH Fazekas score β = 0.21, 95% CI [0.11 to 0.3]; WMH volume β = 0.14, 95% CI [0.09 to 0.19]) or visual score. Individual PVS size showed the strongest association with WMH. Conclusions Computational measures reflecting individual PVS size, length and width were more strongly associated with WMH, stroke and hypertension than computational count or visual PVS score. Multidimensional computational PVS metrics may increase sensitivity to detect associations of PVS with risk exposures, brain lesions and neurological disease, provide greater anatomic detail and accelerate understanding of disorders of brain fluid and waste clearance., Graphical abstract Image, graphical abstract

Both anxiety and aggression commonly co-occur with ADHD symptoms. Two competing hypotheses describing the role of anxiety in aggression associated with ADHD symptoms have previously been advanced. The exacerbation hypothesis proposes that the presence of anxiety increases the risk of aggression in the context of ADHD symptoms. The attenuation hypothesis proposes that the presence of anxiety protects against aggression in the context of ADHD symptoms. We tested these hypotheses using moderated cross-lagged panel models in the Zurich project on social development from childhood to adulthood (z-proso) sample using both self-report (3 waves) and informant-report (8 waves) data spanning ages 7–17. We found evidence that anxiety protects against both reactive and proactive aggression; however, the effect was direct: there was no evidence for anxiety moderating the strength of ADHD symptom-aggression links. Results suggest that anxiety likely plays an important role in inhibiting aggression but does not interact with ADHD symptoms in the manner predicted by either the exacerbation or attenuation hypothesis.

OBJECTIVES: It is well-known that in cross-sectional analyses, agreement between informants is modest as best when rating attention-deficit/hyperactivity disorder and other disruptive behaviour disorder symptoms. We here aimed to develop recommendations for the use of multi-informant data in the context of longitudinal developmental analyses that examine symptom trajectories over time. METHOD: Using parallel process modelling, we estimated parent-teacher agreement in inattention and hyperactivity/impulsivity symptom initial levels and slopes across the elementary school years (ages 7, 9, and 11) for a community sample of n = 1,388 youth. We also used these models to examine whether initial levels and slopes differed significantly across informants. RESULTS: Informant agreement was low to moderate and higher for inattention slopes (r = .47) than for hyperactivity/impulsivity slopes (r = .23). Parents and teachers reported opposite developmental trends for inattention with teachers reporting declines and parents reporting increases over time. Parents reported overall higher levels of hyperactivity/impulsivity, but there were no average informant differences in slopes. CONCLUSION: Of the options available, we recommend specifying separate but correlated factors for different informants in developmental analyses of attention-deficit/hyperactivity disorder. This can be achieved within latent growth curve and growth mixture models.

In the current study, we fit confirmatory bi-factor models to the items of the Autism Spectrum Quotient (AQ) and Autism Spectrum Quotient Short Form (AQ-S) in order to assess the extents to which the items of each reflect general versus specific factors. The models were fit in a combined sample of individuals with and without a clinical diagnosis of autism spectrum disorders. Results indicated that, with the exception of the Attention to Details factor in the AQ and the Numbers/Patterns factors in the AQ-S, items primarily reflected a general factor. This suggests that when attempting to estimate an association between a specific symptom measured by the AQ or AQ-S and some criterion, associations will be confounded by the general factor. To resolve this, we recommend using a bi-factor measurement model or factor scores from a bi-factor measurement whenever hypotheses about specific symptoms are being assessed.

Cerebral small vessel disease (SVD) may cause cognitive dysfunction. We tested the association between the combined presence of magnetic resonance imaging (MRI) features of SVD and cognitive ability in older age. Cognitive testing and brain MRI were performed in 680 older participants. MRI presence of lacunes, white matter hyperintensities, microbleeds, and perivascular spaces were summed in a score of 0–4 representing all SVD features combined. We also applied latent variable modeling to test whether the 4 MRI features form a unitary SVD construct. The SVD score showed significant associations with general cognitive ability. Latent variable modeling indicated that the 4 MRI markers formed a unitary construct, which showed consistent associations with cognitive ability compared with the SVD score. Total MRI load of SVD is associated with lower general cognitive ability in older age. The total SVD score performed consistently with the more complex latent variable model, suggesting validity and potential utility in future research for determining total SVD load.

There are concerns that females with autism spectrum disorders (ASD) may be underidentified because of factors such as better camouflaging and poorer recognition of the signs of ASD in females. One stage at which females may be underidentified is during screening. In this study, we, therefore, evaluated whether the autism spectrum quotient (AQ-10), a brief recommended screening instrument for ASD in adults suspected of having ASD, showed any evidence of underestimating symptoms in females. Our results broadly replicate those of an earlier study in finding no strong evidence that the AQ-10 is biased against females. However, to achieve better performance in females, we suggest that one item be replaced with an item measuring more “female” manifestations of ASD.

Objective To assess brain structural connectivity in relation to cognitive abilities in healthy ageing, and the mediating effects of white matter hyper‐intensity (WMH) volume. Methods MRI data were analysed in 558 members of the Lothian Birth Cohort 1936. Brains were segmented into 85 regions and combined with tractography to generate structural connectomes. WMH volume was quantified. Relationships between whole‐brain connectivity, assessed using graph theory metrics, and four major domains of cognitive ability (visuospatial reasoning, verbal memory, information processing speed and crystallized ability) were investigated, as was the mediating effects of WMH volume on these relationships. Results Visuospatial reasoning was associated with network strength, mean shortest path length, and global efficiency. Memory was not associated with any network connectivity metric. Information processing speed and crystallized ability were associated with all network measures. Some relationships were lost when adjusted for mean network FA. WMH volume mediated 11%–15% of the relationships between most network measures and information processing speed, even after adjusting for mean network FA. Conclusion Brain structural connectivity relates to visuospatial reasoning, information processing speed and crystallized ability, but not memory, in this relatively healthy age‐homogeneous cohort of 73 year olds. When adjusted for mean FA across the network, most relationships are lost, except with information processing speed suggesting that the underlying topological network structure is related to this cognitive domain. Moreover, the connectome‐processing speed relationship is partly mediated by WMH volume in this cohort. Hum Brain Mapp 39:622–632, 2018. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9-85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large "mega-family". We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. © 2014 Elsevier Inc.

Brain tissue deterioration is a significant contributor to lower cognitive ability in later life; however, few studies have appropriate data to establish how much influence prior brain volume and prior cognitive performance have on this association. We investigated the associations between structural brain imaging biomarkers, including an estimate of maximal brain volume, and detailed measures of cognitive ability at age 73 years in a large (N = 620), generally healthy, community-dwelling population. Cognitive ability data were available from age 11 years. We found positive associations (r) between general cognitive ability and estimated brain volume in youth (male, 0.28; females, 0.12), and in measured brain volume in later life (males, 0.27; females, 0.26). Our findings show that cognitive ability in youth is a strong predictor of estimated prior and measured current brain volume in old age but that these effects were the same for both white and gray matter. As 1 of the largest studies of associations between brain volume and cognitive ability with normal aging, this work contributes to the wider understanding of how some early-life factors influence cognitive aging.

Screening tools can provide an indication of whether a child may have an intellectual disability (ID). Item response theory (IRT) analyses can be used to assess whether the statistical properties of the tools are such that their utility extends beyond their use as a screen for ID. We used non-parametric IRT scaling analyses to investigate whether the Child and Adolescent Intellectual Disability Screening Questionnaire (CAIDS-Q) possessed the statistical properties that would suggest its use could be extended to estimate levels of functional ability and to estimate which (if any) features associated with intellectual impairment are consistently indicative of lower or higher levels of functional ability. The validity of the two proposed applications was assessed by evaluating whether the CAIDS-Q conformed to the properties of the Monotone Homogeneity Model (MHM), characterised by uni-dimensionality, local independence and latent monotonicity and the Double Monotone Model (DMM), characterised by the assumptions of the MHM and, in addition, of non-intersecting item response functions. We analysed these models using CAIDS-Q data from 319 people referred to child clinical services. Of these, 148 had a diagnosis of ID. The CAIDS-Q was found to conform to the properties of the MHM but not the DMM. In practice, this means that the CAIDS-Q total scores can be used to quickly estimate the level of a person's functional ability. However, items of the CAIDS-Q did not show invariant item ordering, precluding the use of individual items in isolation as accurate indices of a person's level of functional ability.

BackgroundThe present study aimed to investigate whether there is an association between type of living environment (urban versus rural) and anxiety, depression and psychosis in the Scottish population.MethodsData were obtained from the Scottish Neighbourhood Statistics database on Scottish Index of Multiple Deprivation and urban–rural classifications for 6505 data zones across Scotland. Multiple regression was used to test the association between prescriptions for psychotropic medication for anxiety, depression and psychosis, and type of living environment according to urban–rural classification, controlling for a range of socio-economic factors.ResultsUrban–rural classification significantly predicted poorer mental health both before (β=−.29) and after (β=−.20) controlling for a large number of socio-economic variables, with more urban areas having higher rates of prescription for psychotropic medication for anxiety, depression and psychosis.LimitationsThe current study focussed on macro-level variables and did not include individual level data. As such, the study did not include data on individual diagnoses, but instead used drug prescriptions for anxiety, depression and psychosis as a proxy for level of affective disorders within data zones.ConclusionMore urban living environments in Scotland are associated with higher rates of prescription for psychotropic medication for anxiety, depression and psychosis.

Associations between brain cortical tissue volume and cognitive function in old age are frequently interpreted as suggesting that preservation of cortical tissue is the foundation of successful cognitive aging. However, this association could also, in part, reflect a lifelong association between cognitive ability and cortical tissue. We analyzed data on 588 subjects from the Lothian Birth Cohort 1936 who had intelligence quotient (IQ) scores from the same cognitive test available at both 11 and 70 years of age as well as high-resolution brain magnetic resonance imaging data obtained at approximately 73 years of age. Cortical thickness was estimated at 81 924 sampling points across the cortex for each subject using an automated pipeline. Multiple regression was used to assess associations between cortical thickness and the IQ measures at 11 and 70 years. Childhood IQ accounted for more than two-third of the association between IQ at 70 years and cortical thickness measured at age 73 years. This warns against ascribing a causal interpretation to the association between cognitive ability and cortical tissue in old age based on assumptions about, and exclusive reference to, the aging process and any associated disease. Without early-life measures of cognitive ability, it would have been tempting to conclude that preservation of cortical thickness in old age is a foundation for successful cognitive aging when, instead, it is a lifelong association. This being said, results should not be construed as meaning that all studies on aging require direct measures of childhood IQ, but as suggesting that proxy measures of prior cognitive function can be useful to take into consideration.

There is a need for brief screening instruments for autistic spectrum disorders (ASD) that can be used by frontline healthcare professionals to aid in the decision as to whether an individual should be referred for a full diagnostic assessment. In this study we evaluated the ability of a short form of the autism spectrum quotient (AQ) questionnaire, the 10 item AQ-10, to correctly classify individuals as having or not having ASD. In a sample of 149 individuals with ASD and 134 controls without an ASD diagnosis, we found that the full AQ (AQ-50) abridged AQ (AQ-S) and AQ-10 all performed well as a screen for ASD. ROC analysis indicated that sensitivity, specificity and area under the curve were very similar at suggested cut-off's for ASD across measures, with little difference in performance between the AQ-10 and full AQ-50. Results indicate the potential usefulness of the AQ-10 as a brief screen for ASD.

It has been suggested that how individuals respond to self-report items relies on cognitive processing. We hypothesized that an individual's level of cognitive ability may influence these processes such that, if there is a hierarchy of items within a particular questionnaire, as demonstrated by Mokken scaling, the strength of that hierarchy will vary according to cognitive ability. Using data on 8,643 men and women from the National Child Development Survey (1958 birth cohort; Power, & Elliott, 2006), we investigated, using Mokken scaling, whether the 14 items that make up the Warwick-Edinburgh Mental Well-Being Scale (Tennant et al., 2007)-completed when the participants were 50 years of age-form a hierarchy and whether that hierarchy varied according to cognitive ability at age 11 years. Among the sample as a whole, we found a moderately strong unidimensional hierarchy of items (Loevinger's coefficient [H] = 0.48). We split participants into 3 groups according to cognitive ability and analyzed the Mokken scaling properties of each group. Only the medium and high cognitive ability groups had acceptable (≥0.3) invariant item ordering (assessed using the HT statistic). This pattern was also found when the 3 cognitive ability groups were assessed within men and women separately. Greater attention should be paid to the content validity of questionnaires to ensure they are applicable across the spectrum of mental ability. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

The primary aim of this article was to provide a structural validation of the 28-item Autism Spectrum Quotient–Short Form questionnaire in a sample of adults with clinically diagnosed autism spectrum disorders ( n = 148). Confirmatory factor analysis demonstrated that the proposed structure, comprising a second-order Social Skills factor subsuming first-order factors of Social Skills, Routine, Switching and Imagination, and a Numbers/Patterns factor showed good acceptable fit to the data ( χ2 = 464.27(345), p < .05; comparative fit index = .91; Tucker Lewis index = .90; root mean squared error of approximation = .048; weighted root mean square residual = 0.98). Summed mean scores for the total sample, and males and females separately, showed no significant differences to previously reported means, with the exception of Numbers/Patterns, for which the current sample reported significantly lower means in both males ( t = 3.37, p < 0.001) and females ( t = 2.33, p < 0.05). The results provide support for both the proposed structure of the AQ-S and the stability of total and subscale mean scores in different samples of participants with autism spectrum disorder diagnoses.

Background: Information on childhood determinants of frailty or allostatic load in later life is sparse. We investigated whether lower intelligence and greater socioeconomic disadvantage in childhood increased the risk of frailty and higher allostatic load and explored the mediating roles of adult socioeconomic position, educational attainment and health behaviours. Methods: Participants were 876 members of the Lothian Birth Cohort 1936 whose intelligence was assessed at age 11. At age 70, frailty was assessed using the Fried criteria. Measurements were made of fibrinogen, triglyceride, total and high-density lipoprotein cholesterol, albumin, glycated haemoglobin, C-reactive protein, BMI, and blood pressure from which an allostatic load score was calculated. Results: In sex-adjusted analyses, lower intelligence and lower social class in childhood were associated with an increased risk of frailty: relative risks (95% confidence intervals) were 1.57 (1.21, 2.03) for a standard deviation decrease in intelligence and 1.48 (1.12, 1.96) for a category decrease in social class. In the fully-adjusted model, both associations ceased to be significant: relative risks were 1.13 (0.83, 1.54) and 1.19 (0.86, 1.61) respectively. Educational attainment had a significant mediating effect. Lower childhood intelligence in childhood, but not social class, was associated with higher allostatic load. The sex-adjusted coefficient for allostatic load for a standard deviation decrease in intelligence was 0.10 (0.07, 0.14). In the fully-adjusted model, this association was attenuated but remained significant (0.05 (0.01, 0.09)). Conclusion: Further research will need to investigate the mechanisms whereby lower childhood intelligence is linked to higher allostatic load in later life.

It has previously been noted that inventories measuring traits that originated in a psychopathological paradigm can often reliably measure only a very narrow range of trait levels that are near and above clinical cutoffs. Much recent work has, however, suggested that autism spectrum disorder traits are on a continuum of severity that extends well into the nonclinical range. This implies a need for inventories that can capture individual differences in autistic traits from very high levels all the way to the opposite end of the continuum. The Autism-Spectrum Quotient (AQ) was developed based on a closely related rationale, but there has, to date, been no direct test of the range of trait levels that the AQ can reliably measure. To assess this, we fit a bifactor item response theory model to the AQ. Results suggested that AQ measures moderately low to moderately high levels of a general autistic trait with good measurement precision. The reliable range of measurement was significantly improved by scoring the instrument using its 4-point response scale, rather than dichotomizing responses. These results support the use of the AQ in nonclinical samples, but suggest that items measuring very low and very high levels of autistic traits would be beneficial additions to the inventory. (PsycINFO Database Record

Diagnostic bias is a concern in autism spectrum conditions (ASC) where prevalence and presentation differ by sex. To ensure that females with ASC are not under-identified, it is important that ASC screening tools do not systematically underestimate autistic traits in females relative to males. We evaluated whether the AQ-10, a brief screen for ASC recommended by the National Institute of Clinical Excellence in cases of suspected ASC, exhibits such a bias. Using an item response theory approach, we evaluated differential item functioning and differential test functioning. We found that although individual items showed some sex bias, these biases at times favored males and at other times favored females. Thus, at the level of test scores the item-level biases cancelled out to give an unbiased overall score. Results support the continued use of the AQ-10 sum score in its current form; however, suggest that caution should be exercised when interpreting responses to individual items. The nature of the item level biases could serve as a guide for future research into how ASC affects males and females differently. Autism Res 2017, 10: 790-800. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

The Learning Disability Screening Questionnaire (LDSQ; McKenzie & Paxton, 2006) was developed as a brief screen for intellectual disability. Although several previous studies have evaluated the LDSQ with respect to its utility as a clinical and research tool, no studies have considered the fairness of the test across males and females. In the current study we, therefore, used a multi-group item response theory approach to assess differential item functioning across gender in a sample of 211 males and 132 females assessed in clinical and forensic settings. Although the test did not show evidence of differential item functioning by gender, it was necessary to exclude one item due to estimation problems and to combine two very highly related items (concerning reading and writing ability) into a single literacy item Thus, in addition to being generally supportive of the utility of the LDSQ, our results also highlight possible areas of weakness in the tool and suggest possible amendments that could be made to test content to improve the test in future revisions.

The current article compares the use of exploratory structural equation modeling (ESEM) as an alternative to confirmatory factor analytic (CFA) models in personality research. We compare model fit, factor distinctiveness, and criterion associations of factors derived from ESEM and CFA models. In Sample 1 ( n = 336) participants completed the NEO-FFI, the Trait Emotional Intelligence Questionnaire–Short Form, and the Creative Domains Questionnaire. In Sample 2 ( n = 425) participants completed the Big Five Inventory and the depression and anxiety scales of the General Health Questionnaire. ESEM models provided better fit than CFA models, but ESEM solutions did not uniformly meet cutoff criteria for model fit. Factor scores derived from ESEM and CFA models correlated highly (.91 to .99), suggesting the additional factor loadings within the ESEM model add little in defining latent factor content. Lastly, criterion associations of each personality factor in CFA and ESEM models were near identical in both inventories. We provide an example of how ESEM and CFA might be used together in improving personality assessment.

It is common to administer measures of autistic traits to those without autism spectrum disorders (ASDs) with, for example, the aim of understanding autistic personality characteristics in non-autistic individuals. Little research has examined the extent to which measures of autistic traits actually measure the same traits in the same way across those with and without an ASD. We addressed this question using a multi-group confirmatory factor invariance analysis of the Autism Quotient Short Form (AQ-S: Hoekstra et al. in J Autism Dev Disord 41(5):589–596, 2011) across those with (n = 148) and without (n = 168) ASD. Metric variance (equality of factor loadings), but not scalar invariance (equality of thresholds), held suggesting that the AQ-S measures the same latent traits in both groups, but with a bias in the manner in which trait levels are estimated. We, therefore, argue that the AQ-S can be used to investigate possible causes and consequences of autistic traits in both groups separately, but caution is due when combining or comparing levels of autistic traits across the two groups.

To investigate and replicate a multisystem model of biological risk, or allostatic load, in a sample of generally healthy older adults.Multigroup confirmatory factor analysis (MG-CFA) was applied to data from the Lothian Birth Cohort 1936 (n = 726). Blood samples were taken at a physical examination. Three markers of inflammation (fibrinogen, interleukin-6, and C-reactive protein), five metabolic markers (high- and low-density lipoprotein, body mass index, glycated hemoglobin, and triglyceride), and blood pressure (mean sitting systolic and diastolic blood pressure) were used to estimate a second-order CFA model of allostatic load. Our sample was split into those taking antihypertensive, anti-inflammatory, lipid-lowering, and diabetes medications (n = 470), and those who were not (n = 256), in order to test the stability of the CFA model across groups.In the nonmedicated sample, a second-order allostatic load model showed good fit to the data. However, the second-order model failed to estimate in the medicated group. The factor correlations between blood pressure and inflammation and metabolism were smaller in magnitude in the medicated group. Invariance analysis on the first-order measurement model suggested significant differences across groups in the associations of low-density lipoprotein and HbA1c with metabolism.Reliable measurement of allostatic load is possible in ageing samples free of medications but is complicated in the presence of medications. MG-CFA represents a highly versatile method for the analysis of allostatic load.

The current study investigated the associations between thyroid stimulating hormone (TSH), free thyroxine (T(4)) and cognitive ability (general ability, memory and processing speed), in a large age homogenous sample (n=659) of generally healthy euthyroid older adults. Associations were considered both at baseline (mean age wave 1=69.5 years; SD=0.8 years) and approximately 3 years later (mean age wave 2=72.5 years; SD=0.7 years). Results indicated mean level decreases across waves in both TSH (t=10.99, p

Background: Sex differences in personality are believed to be comparatively small. However, research in this area has suffered from significant methodological limitations. We advance a set of guidelines for overcoming those limitations: (a) measure personality with a higher resolution than that afforded by the Big Five; (b) estimate sex differences on latent factors; and (c) assess global sex differences with multivariate effect sizes. We then apply these guidelines to a large, representative adult sample, and obtain what is presently the best estimate of global sex differences in personality. Methodology/Principal Findings: Personality measures were obtained from a large US sample (N = 10,261) with the 16PF Questionnaire. Multigroup latent variable modeling was used to estimate sex differences on individual personality dimensions, which were then aggregated to yield a multivariate effect size (Mahalanobis D). We found a global effect size D = 2.71, corresponding to an overlap of only 10% between the male and female distributions. Even excluding the factor showing the largest univariate ES, the global effect size was D = 1.71 (24% overlap). These are extremely large differences by psychological standards. Significance: The idea that there are only minor differences between the personality profiles of males and females should be rejected as based on inadequate methodology. © 2012 Del Giudice et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Allostatic load (AL) has been proposed as a general framework for understanding the cumulative effects of life stress on individuals. Despite growing interest in AL, limited research has been conducted on aging samples. We consider the association of AL (operationalized by a range of inflammatory, cardiovascular, and metabolic measures) with a range of brain volume measurements and cognitive ability in a large cohort sample of older adults (n ¼ 658, mean age ¼ 72.5 years, standard deviation ¼ 0.7) using structural equation modeling. AL was significantly inversely associated with total brain volume (range of stan- dardized b ¼� 0.16 to � 0.20) and white-matter volume (� 0.35 to � 0.36) and positively with hippo- campal volume (0.10e0.15) but not gray-matter volume (0.04). AL was also significantly inversely associated with general cognitive ability (range b ¼� 0.13 to � 0.20), processing speed (� 0.20 to � 0.22), and knowledge (� 0.18 to � 0.20) but not memory or nonverbal reasoning. The associations of AL with cognitive abilities were not mediated by these brain volume measures. AL did not predict cognitive change from age 11 to approximately age 73. The findings suggest a link between AL and later life brain health and cognitive functioning.

Cerebral white matter hyperintensities (WMH) reflect accumulating white matter damage with aging and impair cognition. The role of childhood intelligence is rarely considered in associations between cognitive impairment and WMH. We studied community-dwelling older people all born in 1936, in whom IQ had been assessed at age 11 years. We assessed medical histories, current cognitive ability and quantified WMH on MR imaging. Among 634 participants, mean age 72.7 (SD 0.7), age 11 IQ was the strongest predictor of late life cognitive ability. After accounting for age 11 IQ, greater WMH load was significantly associated with lower late life general cognitive ability (β = −0.14, p < 0.01) and processing speed (β = −0.19, p < 0.001). WMH were also associated independently with lower age 11 IQ (β = −0.08, p < 0.05) and hypertension. In conclusion, having more WMH is significantly associated with lower cognitive ability, after accounting for prior ability, age 11IQ. Early-life IQ also influenced WMH in later life. Determining how lower IQ in youth leads to increasing brain damage with aging is important for future successful cognitive aging.