Sex/gender differences in general cognitive abilities: an investigation using the Leiter-3.

Research has shown that differences between males and females are not in general intelligence, but only in some specific factors and tasks. We used the Italian standardization of the Leiter-3, which is a completely nonverbal cognitive battery, to investigate the nature of sex/gender (we used sex/gender to reflect the awareness that the effects of biological 'sex' and socially constructed 'gender' cannot be easily separated and that most individuals' identities are informed by both sex and gender) differences. In doing so we used a multigroup confirmatory factor analysis approach. Results confirmed that males and females perform similarly in general intelligence, but present with some specificities. Males perform better on some, but not all, tasks requiring the spatial manipulation of the stimuli, but females consistently outperform males in tasks such as the nonverbal Stroop, requiring inhibition and attention control to a larger extent. The clinical and practical implications of our findings are considerable. The identification of specific cognitive strengths and weaknesses in males and females underscores the importance of tailored approaches in clinical assessments and interventions.

The Intellectual Profile of Adults with Specific Learning Disabilities.

Despite growing research on adults with specific learning disabilities (SLDs), evidence concerning their intellectual profile remains scarce. The present study examined the results of the administration of the Wechsler Adult Intelligence Scale-Fourth Edition to 301 adults diagnosed with SLDs and compared them to the results obtained from previous studies with a large sample of children with SLDs. The results showed that: (1) as observed among children, adults with SLDs also presented higher scores in the subtests implying reasoning (associated with the General Ability Index, GAI) and lower scores in the subtests involving working memory and processing speed; (2) the discrepancy between full-scale IQ and the GAI had a good predictive value in discriminating adults with and without SLDs; (3) the four-factor hierarchical structure of intelligence proposed for the general adult population held for adults with SLDs as well, even though there were substantial differences in the loadings and a five-factor structure could be more appropriate; (4) similarities as well as strong differences were present between adults and children with SLDs. In adults, scores on subtests were generally lower, particularly in working memory and processing speed. However, in some cases, scores were equal or even higher (as in the "Similarity" subtest) among adults, meaning that the discrepancy between the full scale and the GAI was accentuated.

Oral language interventions can improve language outcomes in children with neurodevelopmental disorders: A systematic review and meta-analysis.

Background: Young people who fail to develop language as expected face significant challenges in all aspects of life. Unfortunately, language disorders are common, either as a distinct condition (e.g., Developmental Language Disorder) or as a part of another neurodevelopmental condition (e.g., autism). Finding ways to attenuate language problems through intervention has the potential to yield great benefits not only for the individual but also for society as a whole. Objectives: This meta-analytic review examined the effect of oral language interventions for children with neurodevelopmental disorders. Search Methods: The last electronic search was conducted in April 2022. Selection Criteria: Intervention studies had to target language skills for children from 2 to 18 years of age with Developmental Language Disorder, autism, intellectual disability, Down syndrome, Fragile X syndrome, and Williams syndrome in randomised controlled trials or quasi-experimental designs. Control groups had to include business-as-usual, waiting list, passive or active conditions. However, we excluded studies in which the active control group received a different type, delivery, or dosage of another language intervention. Eligible interventions implemented explicit and structured activities (i.e., explicit instruction of vocabulary, narrative structure or grammatical rules) and/or implicit and broad activities (i.e., shared book reading, general language stimulation). The intervention studies had to assess language skills in receptive and/or expressive modalities. Data Collection and Analysis: The search provided 8195 records after deduplication. Records were screened by title and abstract, leading to full-text examinations of 448 records. We performed Correlated and Hierarchical Effects models and ran a retrospective power analysis via simulation. Publication bias was assessed via p-curve and precision-effect estimate. Main Results: We examined 38 studies, with 46 group comparisons and 108 effects comparing pre-/post-tests and eight studies, with 12 group comparisons and 21 effects at follow-up. The results showed a mean effect size of d = 0.27 at the post-test and d = 0.18 at follow-up. However, there was evidence of publication bias and overestimation of the mean effects. Effects from the meta-analysis were significantly related to these elements: (1) receptive vocabulary and omnibus receptive measures showed smaller effect sizes relative to expressive vocabulary, grammar, expressive and receptive discourse, and omnibus expressive tests; and (2) the length of the intervention, where longer sessions conducted over a longer period of time were more beneficial than brief sessions and short-term interventions. Neither moderators concerning participants' characteristics (children's diagnosis, diagnostic status, age, sex, and non-verbal cognitive ability and severity of language impairment), nor those regarding of the treatment components and implementation of the language interventions (intervention content, setting, delivery agent, session structure of the intervention or total number of sessions) reached significance. The same occurred to indicators of study quality. The risk of bias assessment showed that reporting quality for the studies examined in the review was poor. Authors' Conclusions: In sum, the current evidence base is promising but inconclusive. Pre-registration and replication of more robust and adequately powered trials, which include a wider range of diagnostic conditions, together with more long-term follow-up comparisons, are needed to drive evidence-based practice and policy.

Maths anxiety and subjective perception of control, value and success expectancy in mathematics.

Mathematics anxiety (MA) is an academic anxiety related to doing, learning and testing mathematics. MA can negatively affect mathematics performance, motivation and maths-heavy science and technology-related career choices. Previous data suggest that subjective perceptions and interpretations of students are key in the genesis of MA. Here, based on expectancy-value and control-value theory, we aimed to identify potential, theoretically based subjective factors probably key to understanding MA. We analysed data from 151 745 fifteen-year-old children from 65 'countries and economies' from the Programme for International Student Assessment (PISA) 2012 dataset. Subjective self-perceptions had a stronger relationship with MA than maths achievement. We found that higher MA was associated with lower perceived control over maths activities and lower subjective expectation of success. Surprisingly, children with higher subjective valuation of maths had higher MA for similar levels of subjective control and success expectancy in maths. Results offer an improved understanding of potential antecedents of MA and suggest that effective interventions could be based on gradual confidence building in maths. These could primarily draw on a deeper understanding of the subject improving subjective success expectancy and feeling of control over maths activities. Cultural variation in findings is discussed.

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

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

Developmental profiles of young children with autism spectrum disorder and global developmental delay: A study with the Griffiths III scales.

The purpose of this study was to identify developmental profiles associated with autism spectrum disorder (ASD) and global developmental delay (DD) in pre-school aged Italian children. Developmental profiles were evaluated by means of a standardized tool widely used for the assessment of psychomotor development in early childhood, the Griffiths III scales, recently adapted and standardized for the Italian population. Specifically, we compared the Griffiths III profiles of children with ASD and DD (ASD + DD) with those of children with DD alone. Moreover, we inspected the psychometric function of single items by comparing children with ASD + DD and children with DD with typically developing (TD) children from the Griffiths III normative sample. In this way, we aimed to isolate the effects of each diagnostic class on psychomotor abilities and on the psychometric function of single items. The ASD + DD and DD groups were found to share the presence of lower age equivalent scores relative to their chronological age in all the developmental domains considered: Foundations of Learning, Language and Communication, Eye and Hand Coordination, Personal-Social-Emotional and Gross Motor Skills. However, the DD group displayed a homogeneous profile with similar levels of delay in all developmental domains, while children with ASD + DD exhibited relative weaknesses in the Language and Communication and Personal-Social-Emotional scales. The analysis of the psychometric function drawn for each item has confirmed different profiles in social-communicative and non-verbal items between the two diagnostic groups and in relation to TD normative sample. The Griffiths III is a valid psychometric tool for identifying atypical developmental profiles and its use may be recommended during the diagnostic process of ASD and DD, to detect specific strengths and weaknesses and guide person-centered treatment.

Navigability of Residential Care Homes From Residents', Family Members', and Staff's Points of View: The Residential Care Home Navigability Scale.

BACKGROUND AND OBJECTIVES: Navigational skills display clear signs of decline with increasing age, especially in pathological aging. Therefore, navigability-the extent to which destinations can be reached with reasonable effort and time-should be considered in residential care home design. We aimed to develop a scale assessing environmental features (i.e., indoor visual differentiation, signage, and layout) for navigability in residential care homes: the Residential Care Home Navigability (RCHN) scale. To this end, we examined whether navigability and its factors were associated with a sense of direction within the residential care homes to different degrees for older adult residents, caregivers, and staff. The relationship between navigability and residential satisfaction was also considered. RESEARCH DESIGN AND METHODS: A sample of 523 participants (230 residents, 126 family caregivers, and 167 staff members) responded to the RCHN, assessed their sense of orientation and general satisfaction, and performed a pointing task. RESULTS: Results confirmed the RCHN scale's 3-level factor structure, good reliability, and validity. A subjective sense of direction, but not pointing task performance, was associated with navigability and its factors. In particular, visual differentiation is positively associated with a sense of direction regardless of group, whereas signage and layout contributed to a better experience of a sense of direction, especially among older residents. Navigability was not related to residents' satisfaction. DISCUSSION AND IMPLICATIONS: Navigability supports perceived orientation in residential care homes, especially for older residents. Moreover, the RCHN is a reliable tool for the assessment of RCHN, with important implications for minimizing spatial disorientation through environmental interventions.

Efficacy of memory training interventions targeting metacognition for older adults: a systematic review and meta-analysis.

OBJECTIVES: This review examined the evidence about training interventions targeting metacognition in improving memory and cognitive performance, metacognitive functioning, and well-being in healthy older adults. METHODS: Studies were identified in the PsycInfo, PubMed, and Scopus databases. The risk of bias was assessed using tools based on the Joanna Briggs criteria. The data were meta-analyzed using random effects models for those training targeting metacognition alone (metacognitive training) or combined with memory strategy training (strategic metacognitive training). RESULTS: Out of the 3,487 articles first identified, 25 studies were eligible for our review (N = 1,768 older adults; mean age range: 64-85 years). Metacognitive training and strategic metacognitive training elicited improvements in memory (d = 0.52 [95% CI: 0.19; 0.84], and d = 0.44 [95% CI: 0.29; 0.58], respectively), metacognitive beliefs (d = 0.58 [95% CI: 0.23; 0.93], and d = 48 [95% CI: 0.28; 0.69], respectively), strategy use (d = 0.98 [95% CI: 0.46; 1.49] and 0.87 [95% CI: 0.14; 1.61], respectively), and memory self-efficacy (d = 0.08 [95% CI: -0.39; 0.56] and 0.55 [95% CI: 0.36; 0.75], respectively). Strategic metacognitive training also improved well-being (d = 0.21 [95% CI: 0.07; 0.35]). CONCLUSION: Interventions targeting metacognition (alone or combined with memory strategy training) have the potential to support older adults' memory and metacognitive functioning. The methodological quality of most studies on the topic was often limited, however. Furthermore, well-designed studies needed to confirm the benefits of such interventions in older age.

The relationship between sleep quality and quality of life in aging: a systematic review and meta-analysis.

This study examined the available literature concerning the association between sleep quality and quality of life (QoL) in autonomous older people with no sleep disorders. A systematic review and meta-analysis were conducted on studies identified in the PsycInfo, PubMed and Scopus databases that examined the associations between QoL and sleep quality in older adults. Our systematic literature search identified 23 studies concerning a total of 21,092 participants (range of mean ages: 58-79 years). The results showed that self-reported sleep quality, but not objective sleep quality, correlated positively with QoL with a moderate effect size (for self-reported sleep quality, the overall estimate of the average effect size was a Pearson's r = .28 [95% CI: .34, .23]; for objective sleep quality, it was r = .01 [.12, -.09]). This also applied to the main domains of QoL concerning physical and psychological health, social relationships and environmental aspects (the estimated average effect sizes ranged from Pearson's r = .13 to r = .35). These findings highlight the influence of sleep quality, and particularly of self-reported sleep quality, on QoL (as a whole and in its specific domains) in older adults with normal aging and no insomnia. This influence should therefore be investigated systematically when examining QoL.

Non-pharmacological interventions targeting sleep quality in older adults: a systematic review and meta-analysis.

OBJECTIVES: This review aimed to examine the available evidence about non-pharmacological interventions (NPIs) aimed at improving sleep quality in older adults without insomnia or dementia.Methods: Studies on NPIs targeting older adults' sleep were searched in the PsycInfo, PubMed and Scopus databases, with no restriction on publication year up to September 2021. Studies on NPIs for older adults with no diagnosed sleep disorders were included, while those on pharmacological therapies and/or concerning pathological samples were excluded. The risk of bias was assessed using tools based on Joanna Briggs' criteria. The data extracted were meta-analyzed using random effects models for subgroups of NPIs.Results: Of the 1,893 records identified, 31 studies on NPIs (N = 2,224; range of mean ages: 60-78 years) were analyzed. All NPIs improved self-reported sleep quality, albeit to a different extent (physical activity: d=.97 - 95% CI=.62, 1.32-; psychological/psychoeducational, or NPIs that combined more than one sleep-targeting activity: d range: .21 to .97). Only the NPIs based on physical activity improved objectively-measured sleep, d=.31 (.04, .57). The methodological quality of most studies was limited.Conclusion: The most often used NPIs targeting sleep rely on physical activity and sensory stimulation with promising results on sleep quality for the former. More data are needed on psychological/psychoeducational NPIs and combined interventions in order to test their effectiveness. The methodological weaknesses of the available studies suggest they their findings should be interpreted with caution.Supplemental data for this article is available online at http://dx.doi.org/10.1080/13607863.2022.2056879.

The structure, profile, and diagnostic significance of intelligence in children with ADHD are impressively similar to those of children with a specific learning disorder.

This study examines the structure, profile, and diagnostic significance of intelligence in a group of 948 children diagnosed with attention deficit/hyperactivity disorder (ADHD) assessed with the WISC-IV and compared with children with specific learning disorders (SLDs) and with typically developing children. Based on four indexes, the WISC-IV configuration found in TD resulted applicable to ADHD, but with generally lower loadings on g. The Perceptual Reasoning and Verbal Comprehension indexes not only had higher loadings compared to the other two indexes but also represented the relative strengths of children with ADHD, as previously observed for children with SLD. In fact, the WISC pattern could be successfully used for discriminating between ADHD and TD, but not between ADHD and SLD. The latter result was not due to a co-occurrence of a learning disorder because the presence or absence of an associated diagnosis of SLD negligibly affected the pattern observed in ADHD. We concluded that the characteristics of intelligence in children with ADHD can be relevant for assessing this disorder, and that ADHD and SLDs share largely similar underlying cognitive features.

Entia Non Sunt Multiplicanda Shall I look for clusters in my cognitive data?

Unsupervised clustering methods are increasingly being applied in psychology. Researchers may use such methods on multivariate data to reveal previously undetected sub-populations of individuals within a larger population. Realistic research scenarios in the cognitive science may not be ideally suited for a successful use of these methods, however, as they are characterized by modest effect sizes, limited sample sizes, and non-orthogonal indicators. This combination of characteristics even presents a high risk of detecting non-existing clusters. A systematic review showed that, among 191 studies published in 2016-2020 that used different clustering methods to classify human participants, the median sample size was only 322, and a median of 3 latent classes/clusters were detected. None of them concluded in favor of a one-cluster solution, potentially giving rise to an extreme publication bias. Dimensionality reduction techniques are almost never used before clustering. In a subsequent simulation study, we examined the performance of popular clustering techniques, including Gaussian mixture model, a partitioning, and a hierarchical agglomerative algorithm. We focused on their ability to detect the correct number of clusters, and on their classification accuracy. Under a reasoned set of scenarios that we considered plausible for the cognitive research, none of the methods adequately discriminates between one vs two true clusters. In addition, non-orthogonal indicators lead to a high risk of incorrectly detecting multiple clusters where none existed, even in the presence of only modest correlation (a frequent case in psychology). In conclusion, it is hard for researchers to be in a condition to achieve a valid unsupervised clustering for inferential purposes with a view to classifying individuals.

Structure of working memory in children from 3 to 8 years old.

Several models of working memory (WM) have been proposed in the literature. Most of the research on the architecture of WM is based on adults or older children, but less is known about younger children. In this study, we tested various models of WM on a sample of 739 Italian children, ranging in age from 3 to 8 years, primarily of European heritage and from medium to medium-high socioeconomic background. Participants were assessed with 12 WM tasks, systematically varying the modality and level of executive control required (based on the number of activities to be performed at once: retention alone, ignoring distractors, and dealing with dual tasks). We examined younger children (n = 501, Mage = 56.8 months, SD = 6.4, 48% boys) and older children (n = 238, Mage = 80.0 months, SD = 9.0, 58% boys) separately using multigroup confirmatory factor analyses. A Bayesian analytical approach was adopted. Our results suggested that a four-factor model distinguishing between verbal, visual, spatial-simultaneous, and spatial-sequential components of WM achieved the best fit. Overall, the WM structure was very similar in the two groups. We further explored this result with an additional model with a central executive factor loaded on high-control tasks only and found evidence for the presence of an executive control component. The contribution of this factor in terms of explained variance was only modest, however. Our findings demonstrate that it is important to distinguish between WM components in young children. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Individuals with Down Syndrome: Editorial.

Down syndrome (DS) is the most common syndromic cause of intellectual disability, so it has long been of interest to researchers [...].

Difficulties of Young Adults With Dyslexia in Reading and Writing Numbers.

Letters and numbers are different domains, and their differentiation increases with schooling. It has nonetheless been argued that reading alphabetic and numerical materials partly involves the same processes, even in adults. Whether individuals with dyslexia have difficulty reading and writing numbers remains to be established. This study examined this issue in a group of 30 young adults with a diagnosis of dyslexia, without any concurrent specific difficulty in processing quantities, compared with a typically developing group matched for gender, age, university attended and course of studies, and approximate calculation ability. The results showed that adults with dyslexia also have severe difficulty in reading and writing numbers. It emerged that their number reading speed correlated moderately with word reading speed. We concluded that dyslexia is specifically related with difficulties in reading and writing not only alphabetic material but also numerical material. Our findings suggest that these abilities should be considered more carefully when assessing and supporting individuals with dyslexia.

Is the Age of Developmental Milestones a Predictor for Future Development in Down Syndrome?

Down Syndrome (DS) is the most common genetic alteration responsible for intellectual disability, which refers to deficits in both intellectual and adaptive functioning. According to this, individuals with Down Syndrome (DS) reach developmental milestones (e.g., sitting, walking, and babbling) in the same order as their typically developing peers, but later in life. Since developmental milestones are the first blocks on which development builds, the aims of the current study are to: (i) expand the knowledge of developmental milestone acquisition; and (ii) explore the relationship between developmental milestone acquisition and later development. For this purpose 105 children/adolescents with DS were involved in this study, divided in two groups, Preschoolers (n = 39) and School-age participants (n = 66). Information on the age of acquisition of Sitting, Walking, Babbling, and Sphincter Control was collected, together with cognitive, motor, and adaptive functioning. Sitting predicted later motor development, but, with age, it became less important in predicting motor development in everyday life. Babbling predicted later language development in older children. Finally, Sphincter Control emerged as the strongest predictor of motor, cognitive, language, and adaptive skills, with its role being more evident with increasing age. Our data suggest that the age of reaching the milestones considered in the study has an influence on successive development, a role that can be due to common neural substrates, the environment, and the developmental cascade effect.

Developmental Trajectories in Spatial Visualization and Mental Rotation in Individuals with Down Syndrome.

BACKGROUND: The analysis of developmental trajectories of visuospatial abilities in individuals with Down Syndrome (DS) remains an unexplored field of investigation to examine in depth. The study aimed to fill such a gap by examining changes in two visuospatial abilities: spatial visualization (the ability to manage spatial stimuli) and mental rotation (the ability to rotate spatial stimuli). METHOD: Eighty-seven participants with DS, aged between 7 and 53 years (forty-seven males and forty females), completed spatial visualization and mental rotation tasks. Changes in these two abilities were analyzed in relation to chronological age and developmental level, the latter derived from Raven's Colored Progressive Matrices. RESULTS: Chronological age was linearly associated with spatial visualization performance, whereas mental rotation performance increased until 14 years of age and then decreased. Developmental level was linearly associated with increased performance in spatial visualization, the trend in mental rotation was segmented with an increase after 5 years of age. Furthermore, developmental trajectories in mental rotation depended on the rotation degree. CONCLUSION: Chronological age explains a modest quote of variance. Developmental level better describes changes in spatial visualization and mental rotation of individuals with DS.

Path Learning in Individuals With Down Syndrome: The Challenge of Learning Condition and Cognitive Abilities.

Analyzing navigational abilities and related aspects in individuals with Down syndrome (DS) is of considerable interest because of its relevance to everyday life. This study investigates path learning, the conditions favoring it, and the cognitive abilities involved. A group of 30 adults with DS and 32 typically-developing (TD) children matched on receptive vocabulary were shown a 4 × 4 Floor Matrix and asked to repeat increasingly long sequences of steps by walking on the grid. The sequences were presented under two learning conditions, one called Oral instructions (participants received verbal instructions such as "turn right" or "turn left"), the other Observation (participants watched the experimenter's moves). Participants were also assessed on verbal and visuospatial cognitive measures. The results showed a similarly better performance in both groups when the Floor Matrix task was administered in the Observation as opposed to the Oral instructions condition. As for the relation with cognitive abilities, in the Floor Matrix task in the Oral instructions condition, individuals with DS showed an effect of both verbal and visuospatial abilities, which was only positive for verbal ability. The effect of verbal and visuospatial abilities was negligible in the TD group. In the Observation condition, performance was predicted by sequential working memory in both groups. Overall, these results shed light on path learning in individuals with DS, showing that they benefited from the Observation condition, and that the involvement of their cognitive abilities depended on the learning condition.

Self-reported sleep quality and dysfunctional sleep-related beliefs in young and older adults: changes in times of COVID-19 lockdown.

OBJECTIVE: This study examined changes due to COVID-19 lockdown in young and older adults' self-reported sleep quality and dysfunctional sleep-related beliefs. METHODS: Adults involved in studies prior to the pandemic were contacted during the COVID-19 lockdown. Seventeen young adults (age range: 18-35 years) and 21 older adults (age range: 65-90 years) agreed to participate. Participants were interviewed by phone (between 27th April and 4th May, 2020) to complete the Pittsburgh Sleep Quality Index (PSQI) and the Dysfunctional Beliefs About Sleep (DBAS) questionnaire they had been administered before the pandemic. RESULTS: In terms of mean changes, the results showed null effect sizes for changes in self-reported sleep quality for both age groups. In young adults, a medium effect size emerged for changes in sleep latency, which increased during lockdown. No changes in any of the self-reported sleep quality dimensions emerged in older adults. In both age groups, the effect sizes for changes in dysfunctional sleep-related beliefs were negligible. In older adults, however, changes in self-reported sleep quality were largely associated with changes in dysfunctional sleep-related beliefs. CONCLUSIONS: Our results suggest that self-reported sleep quality and dysfunctional sleep-related beliefs were not affected by the COVID-19 lockdown in young or older adults. They also suggest that it might be useful to consider changes in dysfunctional sleep-related beliefs to better capture the impact of stressful events (such as a period of quarantine) on sleep quality, especially where older adults are concerned.

Dyslexia treatment studies: A systematic review and suggestions on testing treatment efficacy with small effects and small samples.

Poor response to treatment is a defining characteristic of reading disorder. In the present systematic review and meta-analysis, we found that the overall average effect size for treatment efficacy was modest, with a mean standardized difference of 0.38. Small true effects, combined with the difficulty to recruit large samples, seriously challenge researchers planning to test treatment efficacy in dyslexia and potentially in other learning disorders. Nonetheless, most published studies claim effectiveness, generally based on liberal use of multiple testing. This inflates the risk that most statistically significant results are associated with overestimated effect sizes. To enhance power, we propose the strategic use of repeated measurements with mixed-effects modelling. This novel approach would enable us to estimate both individual parameters and population-level effects more reliably. We suggest assessing a reading outcome not once, but three times, at pre-treatment and three times at post-treatment. Such design would require only modest additional efforts compared to current practices. Based on this, we performed ad hoc a priori design analyses via simulation studies. Results showed that using the novel design may allow one to reach adequate power even with low sample sizes of 30-40 participants (i.e., 15-20 participants per group) for a typical effect size of d = 0.38. Nonetheless, more conservative assumptions are warranted for various reasons, including a high risk of publication bias in the extant literature. Our considerations can be extended to intervention studies of other types of neurodevelopmental disorders.