Assessment of Intelligence in the Preschool Period

A Systematic Review of Neurodevelopmental Assessments in Infancy and Early Childhood: Developing a Conceptual Framework, Repository of Measures, and Clinical Recommendations

The first 6 years of life are when 90% of brain development occurs, setting the foundation for lifelong neurodevelopment. The field of infant and early childhood neurodevelopment has made marginal advancements since introduced in 1988. There remains a gap in knowledge around early neurodevelopmental domains and trajectories given that there are few established assessment procedures for infants and young children and controversies around reserving assessments until school age. Throughout this systematic review, we (1) identified neurodevelopmental assessment measures employed in the literature by domain and age of assessment, (2) compiled a repository of 608 domain-specific neurodevelopmental assessment measures, and (3) established a preliminary conceptual framework for cross-domain neurodevelopmental assessments across infancy and early childhood. This review adhered to PRISMA guidelines and spanned three databases (PsycINFO, MEDLINE, PubMed). Articles were reviewed for (1) infancy and early childhood (0-6 years), (2) neurodevelopmental measures, and (3) English language. This systematic review spanned 795 articles from 1978 to 2020 with international representation. Advancements in assessment methods (e.g. measures, domains, frameworks) are essential for the evaluation of early neurodevelopmental profiles to inform early interventions, thus harnessing the neuroplasticity and dynamic development notable during early childhood. We hope this work catalyzes future research and clinical guidelines around early assessments methods.

Associations between early childhood poverty and cognitive functioning throughout childhood and adolescence: A 14-year prospective longitudinal analysis of the Mauritius Child Health Project

Associations between childhood poverty and cognitive outcomes have been examined from multiple perspectives. However, most evidence is based on cross-sectional data or longitudinal data covering only segments of the developmental process. Moreover, previous longitudinal research has mostly relied on data from Western nations, limiting insights of poverty dynamics in low- and middle-income countries. Here, we use data from the Mauritius Child Health Project, a large-scale prospective longitudinal study conducted in a then low-income country, to examine long-term associations between poverty in early childhood and cognitive performance across childhood and adolescence. Poverty-related factors were assessed at age 3 years and comprised indicators of psychosocial adversity and malnutrition. Cognitive functioning was assessed at ages 3 and 11 years by using standardized intelligence measures and at age 17 years by means of a computerized test battery. Using multiple hierarchical regression models, we found that chronic malnutrition and parental characteristics showed similar-sized, independent associations with initial cognitive functioning at age 3 as well as at age 11 years. For age 17 years, however, associations with early childhood risk factors vanished and instead, cognitive functioning was predicted by performance on prior cognitive assessments. Sex was also found to be a powerful predictor of cognitive trajectories, with boys improving and girls worsening over time, regardless of the level of their initial exposure to risk. The current findings indicate that, to prevent cognitive impairment, interventions tackling poverty and malnutrition should focus on the infancy period and be designed in a gender-sensitive way.

Development and Validation of Prediction Models for Developmental and Intellectual Outcome Following Pediatric Epilepsy Surgery

BACKGROUND AND OBJECTIVES

To (1) identify predictors of postoperative intelligence and developmental quotients (IQ/DQ) and (2) develop and validate clinically applicable IQ/DQ prediction models.

METHODS

We retrospectively analyzed neuropsychological outcomes and their possible determinants for children treated in Bethel and Utrecht since 1990. We performed separate analyses for patients with IQ and those with only DQ available. We developed prediction models based on presurgical determinants to predict dichotomized levels of performance (IQ≥85, IQ≥70, DQ≥50).

RESULTS

IQ/DQ data before and two years after surgery were available for 492 patients (IQ n=365, DQ n=127). At a cutoff-level ±10 points, the chance of improvement was considerably higher than the chance of deterioration (IQ 37.3% vs. 6.6% and DQ 31.5% vs. 15.0%, respectively). Presurgical IQ/DQ was the strongest predictor of postoperative cognition (IQ r=0.85, p<.001, DQ: r=0.57, p<.001).Two IQ models were developed in the Bethel cohort (n=258) and externally validated in the Utrecht cohort (n=102). For DQ, we developed the model in the Bethel cohort and used 10-fold cross-validation. Models allowed good prediction at all three cutoff-levels (correct classification for IQ≥85=86%, IQ≥70=91%, DQ≥50=76%). External validation of the IQ models showed high accuracy (IQ≥85: 0.82, CI 0.75-0.91, IQ≥70: 0.84, CI 0.77-0.92) and excellent discrimination (ROC curves IQ≥85: AUC 0.90, CI 0.84-0.96; IQ≥70: AUC 0.92, CI 0.87-0.97).

DISCUSSION

After epilepsy surgery in children, the risk of cognitive deterioration is very low. Presurgical development has a strong impact on the postoperative trajectory. The presented models can improve presurgical counseling of patients and parents by reliably predicting cognitive outcomes.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for children undergoing epilepsy surgery presurgical IQ/DQ was the strongest predictor of postoperative cognition.

Cognitive and Motor Outcome in Patients with Early-Detected Central Congenital Hypothyroidism Compared with Siblings

CONTEXT

Early treatment of primary congenital hypothyroidism (CH) prevents irreversible brain damage. Contrary to primary CH, outcome studies on central CH are scarce. Most patients with central CH have multiple pituitary hormone deficiencies (MPHD); these patients are also at risk for neonatal hypoglycemia.

OBJECTIVE

To assess cognitive and motor outcome in patients with early-treated central CH detected by the Dutch neonatal screening.

METHODS

In this cross-sectional study, primary outcome full-scale intelligence quotient (FSIQ) was measured in patients with MPHD and patients with isolated central CH born between January 1, 1995, and January 1, 2015, with siblings as controls. Secondary outcomes were intelligence test subscales and motor function. Linear mixed models were used to compare both patient groups and siblings, followed by post hoc tests in case of significant differences.

RESULTS

Eighty-seven patients (52 MPHD; 35 isolated central CH) and 52 siblings were included. Estimated marginal means for FSIQ were 90.7 (95% CI 86.4-95.0) in patients with MPHD and 98.2 (95% CI 93.0-103.5) in patients with isolated central CH. While patients with MPHD scored lower FSIQs than siblings (mean difference -7.9 points, 95% CI -13.4 to -2.5; P = .002), patients with isolated central CH did not. Processing speed was lower in both patient groups than in siblings (mean differences -10.5 and -10.3 points). Motor difficulties occurred significantly more often in patients (33%) versus siblings (5%; P = .004).

CONCLUSION

In early-treated central CH, FSIQ is comparable with siblings in patients with isolated central CH, while patients with MPHD have a significantly lower FSIQ. This may be explained by disease-specific consequences of MPHD, such as neonatal hypoglycemia and more severe hypothyroidism.

Academic performance and intelligence quotient of primary school children in Enugu

Introduction

intellectual capacity measured as intelligence quotient (IQ) is one of the determinants of school performance of children. It influences academic achievement, future personal health, social well-being and therefore, is of public health significance. The objective of the study was to determine the intelligence quotient (IQ) and academic performance of primary school children in Enugu-East LGA.

Methods

children who met the inclusion criteria were recruited from both public and private primary schools in the Local Government Area (LGA) using a proportionate multistage sampling technique. Academic performance was classified into high, average and low academic using past records of class assessment. Intelligence quotient was assessed using the Raven´s Standard Progressive Matrices (RSPM) and was grouped into optimal and suboptimal. A semi-structured questionnaire was used to obtain data such as-age, gender, socio-economic indices and family size of the study participants. Analysis was done with Statistical Package for Social Sciences (IBM-SPSS).

Results

a total of 1,122 pupils aged 6 to 12 years were recruited. Optimal IQ and high academic performance were found in 54.0% and 58.8% of the study participants. Being from upper social class, in private school, and family size less than 4 were the significant determinants of high IQ and good academic performance (p<0.001).

Conclusion

low socio-economic status, large family size and public school attendance impact negatively on IQ and academic performance. Hence, measures to curb large family sizes (i.e.>4 children) and improve the socio-economic status of families are needed environmental measures to improve intelligence and academic performance.

Cognitive Outcomes of Young Children After Prenatal Exposure to Medications for Opioid Use Disorder: A Systematic Review and Meta-analysis

IMPORTANCE

The number of children with prenatal opioid exposure to medication for addiction treatment (MAT) with methadone and buprenorphine for maternal opioid use disorder is increasing, but the associations of this exposure with cognitive outcomes are not well understood.

OBJECTIVE

To examine the strength and consistency of findings in the medical literature regarding the association of prenatal exposure to MAT with early childhood cognitive development, particularly when accounting for variables outside MAT exposure.

DATA SOURCES

A search strategy obtained publications from PubMed, CINAHL, PsycINFO, Web of Science, and Embase from January 1972 to June 2019. Reference lists from identified articles were searched.

STUDY SELECTION

Inclusion criteria were cohort studies, studies including children aged 1 to 60 months with at least 2 months of prenatal MAT exposure, studies using standardized direct-observation testing scales, and studies reporting means and SDs. Case reports, case series, historical controls, and reviews were excluded.

DATA EXTRACTION AND SYNTHESIS

Two authors independently selected studies for inclusion, extracted data, and assessed study quality. Data extracted included demographic characteristics, covariates, sources of bias, and effect estimates. Meta-analysis was performed using random-effects models. This study was conducted according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Data extraction and synthesis were conducted between January 2018 and August 2019.

MAIN OUTCOMES AND MEASURES

Cognitive test scores and demographic variability between exposed and unexposed groups.

RESULTS

A total of 16 unique cohorts, described in 27 articles and including 1086 children (485 [44.7%] with MAT exposure), were included in a quantitative synthesis. On meta-analysis, MAT exposure was associated with lower cognitive development scores (pooled standardized mean difference, -0.57; 95% CI, -0.93 to -0.21; I2 = 81%). Multiple subanalyses on demographic characteristics (ie, maternal education, race/ethnicity, socioeconomic status, prenatal tobacco exposure, infant sex) were conducted. In the subanalysis of studies with comparable prenatal exposure to tobacco smoke, the association of MAT exposure with cognitive scores was no longer statistically significant and became homogeneous (standardized mean difference, -0.11; 95% CI, -0.42 to 0.20; I2 = 0%).

CONCLUSIONS AND RELEVANCE

In this study, predefined subanalyses demonstrated how poor recruitment, particularly imbalances in maternal tobacco use, could contribute to a negative overall association of cognitive development test scores with prenatal MAT exposure. Promoting tobacco cessation for pregnant women with opioid use disorder should be prioritized in this high-risk population.

Intelligence as a Developing Function: A Neuroconstructivist Approach

The concept of intelligence encompasses the mental abilities necessary to survival and advancement in any environmental context. Attempts to grasp this multifaceted concept through a relatively simple operationalization have fostered the notion that individual differences in intelligence can often be expressed by a single score. This predominant position has contributed to expect intelligence profiles to remain substantially stable over the course of ontogenetic development and, more generally, across the life-span. These tendencies, however, are biased by the still limited number of empirical reports taking a developmental perspective on intelligence. Viewing intelligence as a dynamic concept, indeed, implies the need to identify full developmental trajectories, to assess how genes, brain, cognition, and environment interact with each other. In the present paper, we describe how a neuroconstructivist approach better explains why intelligence can rise or fall over development, as a result of a fluctuating interaction between the developing system itself and the environmental factors involved at different times across ontogenesis.

The Structural and Functional Organization of Cognition

This article proposes that what have been historically and contemporarily defined as different domains of human cognition are served by one of four functionally- and structurally-distinct areas of the prefrontal cortex (PFC). Their contributions to human intelligence are as follows: (a) BA9, enables our emotional intelligence, engaging the psychosocial domain; (b) BA47, enables our practical intelligence, engaging the material domain; (c) BA46 (or BA46-9/46), enables our abstract intelligence, engaging the hypothetical domain; and (d) BA10, enables our temporal intelligence, engaging in planning within any of the other three domains. Given their unique contribution to human cognition, it is proposed that these areas be called the, social (BA9), material (BA47), abstract (BA46-9/46) and temporal (BA10) mind. The evidence that BA47 participates strongly in verbal and gestural communication suggests that language evolved primarily as a consequence of the extreme selective pressure for practicality; an observation supported by the functional connectivity between BA47 and orbital areas that negatively reinforce lying. It is further proposed that the abstract mind (BA46-9/46) is the primary seat of metacognition charged with creating adaptive behavioral strategies by generating higher-order concepts (hypotheses) from lower-order concepts originating from the other three domains of cognition.

Comparison of Measures of Ability in Adolescents with Intellectual Disability

Finding the most appropriate intelligence test for adolescents with Intellectual Disability (ID) is challenging given their limited language, attention, perceptual, and motor skills and ability to stay on task. The study compared performance of 23 adolescents with ID on the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), one of the most widely used intelligence tests, and three non-verbal IQ tests, the Raven's Colored Progressive Matrices (RCPM), the Test of Non-verbal Intelligence-Fourth Edition and the Wechsler Non-verbal test of Ability. Results showed that the WISC-IV Full Scale IQ raw and scaled scores were highly correlated with total scores from the three non-verbal tests, although the correlations were higher for raw scores, suggesting they may lead to better understanding of within group differences and what individuals with ID can do at the time of assessment. All participants attempted more questions on the non-verbal tests than the verbal. A preliminary analysis showed that adolescents with ID without ASD (n = 15) achieved higher scores overall than those presenting with ID+ASD (n = 8). Our findings support the view that short non-verbal tests are more likely to give a similar IQ result as obtained from the WISC-IV. In terms of the time to administer and the stress for participants, they are more appropriate for assessing adolescents with ID.

Accuracy of Short Forms of the Dutch Wechsler Preschool and Primary Scale of Intelligence

This article investigated the accuracy of six short forms of the Dutch Wechsler Preschool and Primary Scale of Intelligence–Third edition (WPPSI-III-NL) in estimating intelligent quotient (IQ) scores in healthy children aged 4 to 7 years ( N = 1,037). Overall, accuracy for each short form was studied, comparing IQ equivalences based on the short forms with the original WPPSI-III-NL Full Scale IQ (FSIQ) scores. Next, our sample was divided into three groups: children performing below average, average, or above average, based on the WPPSI-III-NL FSIQ estimates of the original long form, to study the accuracy of WPPSI-III-NL short forms at the tails of the FSIQ distribution. While studying the entire sample, all IQ estimates of the WPPSI-III-NL short forms correlated highly with the FSIQ estimates of the original long form (all rs ≥ .83). Correlations decreased significantly while studying only the tails of the IQ distribution ( rs varied between .55 and .83). Furthermore, IQ estimates of the short forms deviated significantly from the FSIQ score of the original long form, when the IQ estimates were based on short forms containing only two subtests. In contrast, unlike the short forms that contained two to four subtests, the Wechsler Abbreviated Scale of Intelligence short form (containing the subtests Vocabulary, Similarities, Block Design, and Matrix Reasoning) and the General Ability Index short form (containing the subtests Vocabulary, Similarities, Comprehension, Block Design, Matrix Reasoning, and Picture Concepts) produced less variations when compared with the original FSIQ score.