Validity of US norms for the Bayley Scales of Infant Development-III in Malawian children

The development of Picture Comprehension Across Early Environments: Evidence From Urban and Rural Toddlers in Western Kenya

Early childhood researchers frequently use learning materials and assessments involving pictures, across different cultures and contexts. However, there is variation in when and how children across cultures and contexts begin to understand and learn from pictures. While children growing up in high-income contexts often have more experience with picture books and other kinds of two-dimensional visual symbols, children growing up in low-income, rural contexts in low- and middle-income countries often have less experience with pictures and other kinds of visual symbols. The current research leverages variation in picture experience within a geographical region to investigate whether previous picture experience is related to toddlers' (1) performance on a picture-based word learning task, and (2) referential understanding, controlling for maternal education, number of toys, caregiver talk, and caregiver play. One hundred and twenty-eight toddlers in urban and rural western Kenya (n = 64 per area), who had varying amounts of picture experience, participated in a picture-based word learning task. Preregistered analyses with the entire sample showed no relation between picture experience and performance on a picture-based word learning task, or between picture experience and referential understanding. However, exploratory analyses found a positive association between picture experience and performance on the picture-based word learning task in the urban sample, but not the rural sample. We found no association between toddlers' referential understanding and picture experience, in either sample. We discuss how these results may inform the efficacy of learning materials and the validity of assessments used with children from diverse global backgrounds.

UNITY: A low-field magnetic resonance neuroimaging initiative to characterize neurodevelopment in low and middle-income settings

Measures of physical growth, such as weight and height have long been the predominant outcomes for monitoring child health and evaluating interventional outcomes in public health studies, including those that may impact neurodevelopment. While physical growth generally reflects overall health and nutritional status, it lacks sensitivity and specificity to brain growth and developing cognitive skills and abilities. Psychometric tools, e.g., the Bayley Scales of Infant and Toddler Development, may afford more direct assessment of cognitive development but they require language translation, cultural adaptation, and population norming. Further, they are not always reliable predictors of future outcomes when assessed within the first 12-18 months of a child's life. Neuroimaging may provide more objective, sensitive, and predictive measures of neurodevelopment but tools such as magnetic resonance (MR) imaging are not readily available in many low and middle-income countries (LMICs). MRI systems that operate at lower magnetic fields (< 100mT) may offer increased accessibility, but their use for global health studies remains nascent. The UNITY project is envisaged as a global partnership to advance neuroimaging in global health studies. Here we describe the UNITY project, its goals, methods, operating procedures, and expected outcomes in characterizing neurodevelopment in sub-Saharan Africa and South Asia.

Relationship Between Neurodevelopmental Areas and Difficulties in Emotional-Behavioural Variables in Children With Typical Development Under 2 Years of Age: Sex Differences

The aim of this study was to examine the relationship between neurodevelopmental areas and possible difficulties in emotional-behavioural variables, and to determine if sex moderated this relationship. A community sample of 231 boys and girls with typical development and with a mean age of 19.84 months was evaluated, using the Bayley-III and CBCL 1.5-5 scales. The main results confirmed: (1) better linguistic abilities in girls in both language areas (receptive communication and expressive communication), finding more evidence according to the Bayesian analysis in expressive communication; (2) in the emotional-behavioural area girls had higher scores in withdrawal; (3) significant negative correlations of low magnitude were found between the Bayley and CBCL scales, particularly in the areas of language and cognitive and internalising and externalising problems; (4) children with low cognitive abilities and those with poor receptive communication showed more inter and externalising difficulties; (5) no significant predictive value or moderating effect of sex was found, (6) the number of participants who simultaneously manifested significant deficits in both domains (neurodevelopmental and emotional-behavioural) was very reduced. Future research should corroborate these results and the characteristics of the relationship found at these early ages. Detecting the population at risk in the first two years of life would enable the implementation of interventions aimed at improving neurodevelopmental deficits and emotional-behavioural problems. Thus, identification of deficits in one domain should lead to evaluation of the other.

The United States reference values of the Bayley III motor scale are suitable in Suriname

To determine if the United States reference values of the Bayley Scales of Infant and Toddler Development, version III motor scale are suitable for Surinamese infants, we assessed 151 healthy infants at 3, 12, 24 and 36 months of age. The mean fine motor, gross motor, and composite scores of the total group did not significantly differ from the US norms, although some significant but not clinically relevant differences were found (lower fine motor scores at 12 months, lower gross motor and total composite scores at 24 months, and higher scores for gross motor and composite scores at 3 months).

Make Bayley III Scores Comparable between United States and German Norms-Development of Conversion Equations

AIM

 Bayley Scales of Infant and Toddler Development (Bayley-III) determines scaled scores and converts these into composite scores. It was shown that applying the German and the U.S. manual leads to different results. This study aims to systematically analyze the differences between the U.S. and German Bayley-III version and to develop conversion equations.

METHODS

 This simulation study generated a dataset of pairs of U.S. and German Bayley-III composite scores (cognitive: n = 4,416, language: n = 240,000, motor: n = 314,000) by converting the same number of achievable tasks for 48 age groups. Bland-Altman plot and regression analyses were performed to develop conversion equations for all age groups.

RESULTS

 German and US Bayley-III scores demonstrate distinct slope and interception for cognitive, language, and motor composite scores. Lower developmental performance leads to higher composite scores with U.S. norms compared with German norms (up to 15 points). These differences varied between age groups. With newly developed conversion equations, the results can be converted (R ²> 0.98).

INTERPRETATION

 This study confirms systematic differences between U.S. and German Bayley test results due to different reference cohorts. Our data consider the full age range and add conversion equations. These findings need to be acknowledged when comparing Bayley Scores internationally.

Ocular and developmental outcomes of a dosing study of bevacizumab for retinopathy of prematurity

PURPOSE

To report 2-year ocular and developmental outcomes for infants receiving low doses of intravitreal bevacizumab for type 1 retinopathy of prematurity (ROP).

METHODS

A total of 120 premature infants (mean birthweight, 687 g; mean gestational age, 24.8 weeks) with type 1 ROP were enrolled in a multicenter, phase 1 dose de-escalation study. One eye per infant received 0.25 mg, 0.125 mg, 0.063 mg, 0.031 mg, 0.016 mg, 0.008 mg, 0.004 mg, or 0.002 mg of intravitreal bevacizumab; fellow eyes when treated received one dosage level higher. At 2 years, 70 of 120 children (58%) underwent ocular examinations; 51 (43%) were assessed using the Bayley Scale of Infant and Toddler Development.

RESULTS

Correlation coefficients for the association of total dosage of bevacizumab with Bayley subscales were -0.20 for cognitive (95% CI, -0.45 to 0.08), -0.15 for motor (95% CI, -0.41 to 0.14), and -0.19 for language (95% CI, -0.44 to 0.10). Fourteen children (21%) had myopia greater than -5.00 D in one or both eyes, 7 (10%) had optic nerve atrophy and/or cupping, 20 (29%) had strabismus, 8 (11%) had manifest nystagmus, and 9 (13%) had amblyopia.

CONCLUSIONS

In this study cohort, there was no statistically significant correlation between dosage of bevacizumab and Bayley scores at 2 years. However, the sample size was small and the retention rate relatively low, limiting our conclusions. Rates of high myopia and ocular abnormalities do not differ from those reported after larger bevacizumab doses.

Survey of Well-Being of Young Children (SWYC): Preliminary Norms for Screening for Developmental Delay in Brazilian Children Younger than 65 Months

OBJECTIVE

The objective of this study was to investigate the reliability and validity of the Developmental Milestones Questionnaire of the Survey of Wellbeing of Young Children Brazilian version (DM-SWYC-BR) and establish the preliminary norms to identify suspected developmental delay in Brazilian children up to 65 months.

METHODS

A psychometric study was conducted on 1535 children from 3 Brazilian regions. The caregivers answered the Brazilian Portuguese cross-culturally adapted version of the DM-SWYC. We calculated the internal consistency and performed an exploratory factor analysis (EFA). The clinical threshold for the suspected developmental delay was set at 85% from the DM-SWYC-BR mean score for each age. The prevalence of suspected delay was calculated using current preliminary cutoffs and original norms.

RESULTS

EFA confirmed the unidimensionality of the DM-SWYC-BR items (average variance extracted = 0.78). Cronbach's alpha was 0.97. At most ages, the difference between the cutoff points in the Brazilian and North American samples was lower than or equal to 2 points, except at 18, 23, 29, 44, 45, 46, and from 54 to 58 months. There was a marked divergence in the prevalence of suspected developmental delay by age ranges using the Brazilian or North American cutoff points. However, the general mean prevalence was quite similar (27.5% vs. 28.2%, respectively).

CONCLUSIONS

We established the cutoff points to interpret the DM-SWYC-BR results when screening for developmental delays in Brazilian children. The satisfactory psychometric properties support its use for screening developmental delays in the public health system. Reliable assessment tools are critical to promoting child development effectively, ensuring timely intervention.

The association of breastfeeding with cognitive development and educational achievement in sub-Saharan Africa: A systematic review

Background

Systematic reviews and meta-analyses of studies mainly from high-income countries suggest that breastfeeding improves cognitive function and educational achievement. However, these associations may be a manifestation of who breastfeeds in these settings rather than an actual effect of breastfeeding. We investigated the association of breastfeeding with cognitive development and educational achievements in sub-Saharan Africa, where breastfeeding is the norm, and socioeconomic status is not strongly correlated with ever breastfeeding.

Methods

We searched Medline, Embase, PsycINFO, Cochrane Central Register of Controlled Trials (CENTRAL), and Africa-Wide Information in January 2021 for studies that assessed the cognitive and educational benefits of breastfeeding in children and adolescents in sub-Saharan Africa. Two reviewers independently screened, extracted, and critically appraised the included studies.

Results

After reviewing 5552 abstracts and 151 full-text articles, seventeen studies on cognitive development and two on educational achievements met our predefined inclusion criteria. The included studies were from ten sub-Saharan African countries and published between 2013 and 2021, with sample sizes ranging from 54 to 6573. Most of the studies (n = 14) were prospective cohort studies, but only nine collected data on breastfeeding prospectively. The studies differed in analytic approaches and cognitive and educational achievements measurements. Of the 17 studies on cognitive development, only four adjusted sufficiently for key confounders. None of these four studies found an overall association between breastfeeding and cognitive development in children or adolescents in sub-Saharan Africa. The two studies on education measured achievements based on the highest grade of school attained, 12 or more years of education, or grade repetition at age 7-11 years. Both studies adjusted for a range of sociodemographic factors and found no evidence that children exclusively breastfed or breastfed for a longer duration have a better educational outcome than sub-optimally breastfed children.

Conclusions

The current evidence from sub-Saharan Africa is limited but does not corroborate previous findings that breastfeeding is associated with improved cognitive development and educational achievement.

Registration

This study is registered with PROSPERO, CRD42021236009.

Gross motor skills trajectory variation between WEIRD and LMIC countries: A cross-cultural study

Aim

This study aimed to examine the prevalence of delays and borderline impaired performance for Brazilian girls and boys and the differences in the motor trajectories (locomotor and ball skills) of girls and boys (3- to 10-years-old) across WEIRD (Western, Educated, Industrial, Rich, and Democratic) countries and Brazil–a low- and middle-income country (LMIC).

Methods

We assessed 1000 children (524 girls; 476 boys), 3- to 10.9-year-old (M = 6.9, SD = 2.1; Girls M = 6.9, SD = 2.0; Boys M = 6.9, SD = 2.1), using the Test of Gross Motor Development-3. Using systematic search, original studies investigating FMS in children using the TGMD-3 were eligible; 5 studies were eligible to have the results compared to the Brazilian sample. One sample t-test to run the secondary data from Irish, American, Finnish, and German children (i.e., mean, standard deviation).

Results

The prevalence of delays and borderline impaired performance was high among Brazilian girls (28.3% and 27.5%) and boys (10.6% and 22.7%). The cross-countries comparisons showed significant (p values from .048 and < .001) overall lower locomotor and ball skills scores for Brazilian children; the only exceptions were skipping, catching, and kicking. We observed stability in performance, across countries, after 8-years-old, and no ceiling effects were found in the samples.

Conclusions

The Brazilian sample emphasized the need for national strategies to foster children’s motor proficiency. Differences in motor opportunities may explain the differences in motor trajectories between children in WEIRD and LMIC countries.

Evaluation of multiple micronutrient supplementation and medium-quantity lipid-based nutrient supplementation in pregnancy on child development in rural Niger: A secondary analysis of a cluster randomized controlled trial

BACKGROUND

It is estimated that over 250 million children under 5 years of age in low- and middle-income countries (LMICs) do not reach their full developmental potential. Poor maternal diet, anemia, and micronutrient deficiencies during pregnancy are associated with suboptimal neurodevelopmental outcomes in children. However, the effect of prenatal macronutrient and micronutrient supplementation on child development in LMIC settings remains unclear due to limited evidence from randomized trials.

METHODS AND FINDINGS

We conducted a 3-arm cluster-randomized trial (n = 53 clusters) that evaluated the efficacy of (1) prenatal multiple micronutrient supplementation (MMS; n = 18 clusters) and (2) lipid-based nutrient supplementation (LNS; n = 18 clusters) as compared to (3) routine iron-folic acid (IFA) supplementation (n = 17 clusters) among pregnant women in the rural district of Madarounfa, Niger, from March 2015 to August 2019 (ClinicalTrials.gov identifier NCT02145000). Children were followed until 2 years of age, and the Bayley Scales of Infant and Toddler Development III (BSID-III) were administered to children every 3 months from 6 to 24 months of age. Maternal report of WHO gross motor milestone achievement was assessed monthly from 3 to 24 months of age. An intention-to-treat analysis was followed. Child BSID-III data were available for 559, 492, and 581 singleton children in the MMS, LNS, and IFA groups, respectively. Child WHO motor milestone data were available for 691, 781, and 753 singleton children in the MMS, LNS, and IFA groups, respectively. Prenatal MMS had no effect on child BSID-III cognitive (standardized mean difference [SMD]: 0.21; 95% CI: -0.20, 0.62; p = 0.32), language (SMD: 0.16; 95% CI: -0.30, 0.61; p = 0.50) or motor scores (SMD: 0.18; 95% CI: -0.39, 0.74; p = 0.54) or on time to achievement of the WHO gross motor milestones as compared to IFA. Prenatal LNS had no effect on child BSID-III cognitive (SMD: 0.17; 95% CI: -0.15, 0.49; p = 0.29), language (SMD: 0.11; 95% CI: -0.22, 0.44; p = 0.53) or motor scores (SMD: -0.04; 95% CI: -0.46, 0.37; p = 0.85) at the 24-month endline visit as compared to IFA. However, the trajectory of BSID-III cognitive scores during the first 2 years of life differed between the groups with children in the LNS group having higher cognitive scores at 18 and 21 months (approximately 0.35 SD) as compared to the IFA group (p-value for difference in trajectory <0.001). Children whose mothers received LNS also had earlier achievement of sitting alone (hazard ratio [HR]: 1.57; 95% CI: 1.10 to 2.24; p = 0.01) and walking alone (1.52; 95% CI: 1.14 to 2.03; p = 0.004) as compared to IFA, but there was no effect on time to achievement of other motor milestones. A limitation of our study is that we assessed child development up to 2 years of age, and, therefore, we may have not captured effects that are easier to detect or emerge at older ages.

CONCLUSIONS

There was no benefit of prenatal MMS on child development outcomes up to 2 years of age as compared to IFA. There was evidence of an apparent positive effect of prenatal LNS on cognitive development trajectory and time to achievement of selected gross motor milestones.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02145000.

Paths of social-emotional development before 3 years old and child development after 5 years old: Evidence from rural China

BACKGROUND

Social-emotional development during the first three years of life is associated with later social-emotional development and cognitive development. In rural China, research has found large shares of children under age three are developmentally delayed, yet little is known about the paths of social-emotional development before age 3 or how developmental paths predict later social-emotional skills and cognitive skills.

AIMS

To investigate the paths of child social-emotional development during ages 0-3 and examine how different paths predict social-emotional development and cognitive development at preschool age.

METHODS

Three waves of longitudinal panel data from 1245 children in rural Western China was collected. Child social-emotional development was measured by the Ages and Stages Questionnaire: Social-Emotional. Child cognitive development was measured by the Bayley Scales of Infant Development and by the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition. Four paths of child social-emotional development were classified: "never" social-emotionally delayed; "persistently" social-emotionally delayed; "improving," or "deteriorating."

RESULTS

331 (27%) were never social-emotionally delayed; 373 children (30%) were persistently social-emotionally delayed; 149 children (12%) experienced improving social-emotional development; and 392 children (31%) experienced deteriorating social-emotional development. Children who were never social-emotionally delayed or who were on an "improving" path had higher social-emotional development at preschool age (p < .01). Children who were persistently social-emotionally delayed (p < .5) and on a deteriorating path (p < .01) had lower social-emotional development at preschool age. Children on the persistently delay path also were shown to have lower levels of cognitive development at preschool age (p < .01).

CONCLUSIONS

Different paths of child social-emotional development before age 3 are associated with different social-emotional and cognitive development at preschool age.

A Comparison Study of the Tehran Norms to the Reference Norms on Children Performance of the Bayley III

Objectives

The Bayley Scales of Infant and Toddler Development (3rd ed.; Bayley III) are widely used to assess cognitive, language, and motor development of children aged 1-42 months. It is unclear whether or not the reference norms of the Bayley III are acceptable for use in other populations or lead to over- or underestimating the developmental status of target children. This study aimed to compare the Tehran norms to the reference norms.

Materials & Methods

We used Bayley III norms to assess cognitive, language, and motor development of 1,674 healthy children from health care centers in Tehran. Differences between the scaled scores were calculated based on the Tehran and reference norms. A one-sample multivariate analysis of variance (MANOVA) was used to control the mean difference scores over all subtests. When MANOVA showed significant differences between the scaled scores based on the Tehran and reference norms, we used univariate analysis to see which subtest and age group led to these significant differences. Finally, the proportions of children with low scores (scaled scores <7 or -1 SD and <4 or -2 SD) based on 2 norms were compared using the McNemar test to determine the over- or underestimation of developmental delay.

Results

The scaled scores based on the Tehran norms varied across values based on the reference norms in all subtests. The mean differences were significant in all 5 subtests (p < .05) with large effect sizes for receptive and expressive communication, fine and gross motor subtests of .20, .23, .14, and .25, respectively, as well as with a small effect size for the cognition subtest of .02. Large effect sizes for all age groups were found for cognition, expressive communication, and fine motor subtests. More children scored below 1 and 2 SD using the Tehran norms. Using the reference norms resulted in underestimation of developmental delay regarding cognitive, receptive and expressive communication, and fine and gross motor skills.

Conclusion

Population-specific norms should be used to identify children with low scores for referral and intervention. The Tehran norms differed from the reference norms for all subtests, and these differences were clinically significant.

A comparison of the performance of normal middle social class Egyptian infants and toddlers with the reference norms of the Bayley Scales -third edition (Bayley III): A pilot study

BACKGROUND

Developmental assessment is an important facility for early detection and intervention of developmental delay in children. Objective: to assess the performance of a sample of middle social class Egyptian infants and toddlers on Bayley Scales of Infant and Toddler Development-third edition (Bayley III), and to compare their cognitive, motor, and communication scores with that of the reference norms.

METHODS

It was a cross-sectional pilot study, included 270 children aged 18-42 months. Mothers filled a questionnaire including questions about family socioeconomic background, perinatal history, and family history. Physical examination and growth assessment of children were performed. Developmental assessment of cognitive, language and motor skills was performed using the Bayley III scales and compared the American norm scores with the Egyptian mean scores.

RESULTS

The mean cognitive, language and motor composite scores were 92.5+18.5, 91.76+ 15.6, and 95.67+18.9 respectively. All were lower than the American mean (100+ 15) with highly significant differences. About one-fourth of the enrolled Egyptian children had below-average composite scores according to the US cutoff point. The ranks of Egyptian children on the American versus the Egyptian percentile curves were significantly different.

CONCLUSION

Mean values of all assessed developmental domains of Egyptian children are within the norm-referenced average of Bayley III, but lower than the recorded American mean. Assessing Egyptian children according to the American norms may result in overestimating developmental delay. This pilot study raised the question about using different cutoff points suitable for the developmental trajectory of Egyptian children. Answering this question needs further studies on Bayley-III after cultural adaptation and standardization, using a larger, more diverse, and representative sample of the Egyptian population.

A comparison of the performance of normal middle social class Egyptian infants and toddlers with the reference norms of the Bayley Scales -third edition (Bayley III): A pilot study

Background

Developmental assessment is an important facility for early detection and intervention of developmental delay in children. Objective: to assess the performance of a sample of middle social class Egyptian infants and toddlers on Bayley Scales of Infant and Toddler Development-third edition (Bayley III), and to compare their cognitive, motor, and communication scores with that of the reference norms.

Methods

It was a cross-sectional pilot study, included 270 children aged 18–42 months. Mothers filled a questionnaire including questions about family socioeconomic background, perinatal history, and family history. Physical examination and growth assessment of children were performed. Developmental assessment of cognitive, language and motor skills was performed using the Bayley III scales and compared the American norm scores with the Egyptian mean scores.

Results

The mean cognitive, language and motor composite scores were 92.5+18.5, 91.76+ 15.6, and 95.67+18.9 respectively. All were lower than the American mean (100+ 15) with highly significant differences. About one-fourth of the enrolled Egyptian children had below-average composite scores according to the US cutoff point. The ranks of Egyptian children on the American versus the Egyptian percentile curves were significantly different.

Conclusion

Mean values of all assessed developmental domains of Egyptian children are within the norm-referenced average of Bayley III, but lower than the recorded American mean. Assessing Egyptian children according to the American norms may result in overestimating developmental delay. This pilot study raised the question about using different cutoff points suitable for the developmental trajectory of Egyptian children. Answering this question needs further studies on Bayley-III after cultural adaptation and standardization, using a larger, more diverse, and representative sample of the Egyptian population.

Neurodevelopmental Outcomes of Young Children Born to HIV-Infected Mothers: A Pilot Study

Introduction: Over 15 million children who were exposed to HIV perinatally but uninfected (HEU) are alive globally, and they are faced with multiple risk factors for poor neurodevelopment. While children who are HIV-infected (HIV+) appear to have worse neurodevelopmental scores compared to children unexposed and uninfected with HIV (HUU), the evidence is mixed in children who are HEU. This small descriptive pilot study aimed to compare neurodevelopmental scores of children who are HIV+, HEU, and HUU in Kenya. Methods: This cross-sectional pilot study included children ages 18-36 months who were HIV+, HEU, or HUU. Neurodevelopment was assessed, along with sociodemographic, lab, and growth data. Statistical analysis included descriptive statistics, one-way ANOVA, chi-squared, and adjusted linear regression models. Results: One hundred seventy two were included (n = 24 HIV+; n = 74 HEU; n = 74 HUU). Mothers of children who were HEU experienced more depressive symptoms (p < 0.001). The only neurodevelopmental differences were found among groups was that children who were HIV+ had higher receptive language scores (p = 0.007). Lower height-for-age z-scores and being left home alone were associated with worse neurodevelopmental scores. Conclusions: Being stunted, left completely alone for at least an hour within the last week, and having higher sociodemographic status were associated with worse neurodevelopmental scores. The higher levels of depressive symptoms within mothers of children who are HEU warrants further investigation.

Early childhood development and parental training interventions in rural China: a systematic review and meta-analysis

INTRODUCTION

Inadequate care during early childhood can lead to long-term deficits in skills. Parenting programmes that encourage investment in young children are a promising tool for improving early development outcomes and long-term opportunities in low-income and middle-income regions, such as rural China.

METHODS

We conducted a systematic review and a meta-analysis to investigate the prevalence of early developmental delays and stimulating parenting practices as well as the effect of parental training programmes on child development outcomes in rural China. We obtained data in English from EconPapers, PubMed, PsycARTICLES, Cochrane Library, Web of Science and Scopus (Elsevier) and in Chinese from China National Knowledge Infrastructure, Wanfang Data and VIP Information. We conducted frequentist meta-analyses of aggregate data and estimated random-effects meta-regressions. Certainty of evidence was rated according to the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

We identified 19 observational studies on the prevalence of developmental delays and stimulating parenting practices for children under 5 years of age (n=19 762) and ten studies on the impact of parental training programmes on early child development (n=13 766). Children's risk of cognitive, language and social-emotional delays in the rural study sites (covering 14 provinces mostly in Central and Western China) was 45%, 46%, and 36%, respectively. Parental training programmes had a positive impact on child cognition, language and social-emotional development.

CONCLUSION

There is evidence to suggest that early developmental delay and the absence of stimulating parenting practices (ie, reading, storytelling and singing with children) may be prevalent across rural, low-income and middle-income regions in Central and Western China. Results support the effectiveness of parental training programmes to improve early development by encouraging parental engagement.

TRIAL REGISTRATION NUMBER

This study was registered with PROSPERO (CRD42020218852).

Effect of a home-based health, nutrition and responsive stimulation intervention and conditional cash transfers on child development and growth: a cluster-randomised controlled trial in Tanzania

Introduction

Evidence on the effects of community health worker (CHW) interventions and conditional cash transfers (CCTs) on child growth and development in sub-Saharan Africa remains sparse.

Methods

We conducted a single-blind, cluster-randomised controlled trial of an integrated home-visiting health, nutrition and responsive stimulation intervention alone and in combination with CCTs to promote antenatal and child clinic attendance from 2017 to 2019 in rural Morogoro Region, Tanzania. Pregnant women and caregivers with a child <1 year of age were enrolled. Twelve villages were randomised to either (1) CHW (n=200 participants), (2) CHW+CCT (n=200) or (3) control (n=193). An intention-to-treat analysis was conducted for the primary trial outcomes of child cognitive, language and motor development assessed with the Bayley Scales of Infant and Toddler Development and child length/height-for-age z-scores (HAZ) at 18 months of follow-up.

Results

The CHW and CHW+CCT interventions had beneficial effects on child cognitive development as compared with control (standardised mean difference (SMD): 0.15, 95% CI 0.05 to 0.24, and SMD: 0.18, 95% CI 0.07 to 0.28, respectively). The CHW+CCT intervention also had positive effects on language (SMD: 0.08, 95% CI 0.01 to 0.15) and motor (SMD: 0.16, 95% CI 0.03 to 0.28) development. Both CHW and CHW+CCT interventions had no effect on HAZ in the primary analysis; however, there were statistically significant positive effects in multivariable analyses. The CHW+CCT group (mean difference: 3.0 visits, 95% CI 2.1 to 4.0) and the CHW group (mean difference: 1.5 visits, 95% CI 0.6 to 2.5) attended greater number of child health and growth monitoring clinic visits as compared to the control group.

Conclusion

Integrated CHW home-visiting interventions can improve child cognitive development and may have positive effects on linear growth. Combining CHW with CCT may provide additional benefits on clinic visit attendance and selected child development outcomes.

Trial registration number

ISRCTN10323949.

Cultural adaptation of the Bayley Scales of Infant and Toddler Development, 3rd Edition for use in Kenyan children aged 18-36 months: A psychometric study

BACKGROUND

The Bayley Scales of Infant and Toddler Development, 3rd Edition (Bayley-III) is frequently used in international child development research. No studies examine its psychometric properties when culturally adapted within the Kenyan context.

AIMS

To culturally adapt the Bayley-III for use in Kenya and evaluate its validity and reliability.

METHODS AND PROCEDURES

Forward and backward translation, cognitive interviews, and a brief pilot of culturally adapted items were performed. This psychometric study was part of another study on children born to mothers with HIV in Eldoret, Kenya. One hundred seventy-two children aged 18-36 months were assessed for cognition, receptive/expressive communication, and fine/gross motor domains using the Bayley-III. Confirmatory factor analysis (CFA), inter-scale Pearson correlations, internal consistency, t-tests, and test-retest reliability were performed.

OUTCOMES AND RESULTS

The mean age of children was 22.8 (SD 4.5) months old; 52.7 % (n = 89) were male. CFA revealed that both two- and three-factor indices had good and comparable fit. Pearson correlations were high between fine motor and receptive communication (r >0.70). Internal consistency was very strong for all of the subtests, with Cronbach coefficient alpha scores ranging from 0.88 to 0.96. Known groups/convergent validity was confirmed with stunting and parental concern for delays. Test-retest reliability was good and did not differ substantially across groups.

CONCLUSIONS AND IMPLICATIONS

The Kenyan adapted Bayley-III is a psychometrically acceptable tool to assess child development. The scaled and composite scores should not be used to define Kenyan developmental norms, but it can be useful for comparing groups within research settings.

Prenatal PM2.5 exposure and neurodevelopment at 2 years of age in a birth cohort from Mexico city

BACKGROUND

Recent studies have reported that air pollution exposure may have neurotoxic properties.

OBJECTIVE

To examine longitudinal associations between prenatal particles less than 2.5 μm in diameter (PM_2.5) exposure and neurodevelopment during the first two years of children's life.

METHODS

Analysis was conducted in PROGRESS, a longitudinal birth cohort between 2007 and 2013 in Mexico City. We used satellite data to predict daily PM_2.5 concentrations at high spatial resolution. Multivariate mixed-effect regression models were adjusted to examine cognitive, language and motor scores in children up to 24 months of age (n = 740) and each trimester-specific and whole pregnancy exposure to PM_2.5.

RESULTS

Models adjusted by child sex, gestational age, birth weight, smoking and mother's IQ, showed that each increase of 1 μg/m³ of PM_2.5 was associated with a decreased language function of -0.38 points (95% CI: -0.77, -0.01). PM_2.5 exposure at third trimester of pregnancy contributed most to the observed association.

CONCLUSION

Our findings suggest that language development up to 24 months of age may be particularly sensitive to PM_2.5 exposure during pregnancy.

Growth and Neurodevelopment Outcomes in HIV-, Tenofovir-, and Efavirenz-Exposed Breastfed Infants in the PMTCT Option B+ Program in Malawi

BACKGROUND

Pregnant and breastfeeding women in Option B+ in Malawi received antiretroviral drugs (ARVs) containing efavirenz (EFV) and tenofovir disoproxil fumarate (TDF). However, effects on growth, renal, bone metabolism, and neurodevelopment of long-term exposure to low doses of these drugs through breast milk in HIV-exposed infants are unclear.

METHODS

Prospective cohorts of TDF-and-EFV-exposed and TDF-and-EFV-unexposed breastfed infants of HIV-infected and HIV-uninfected mothers in Option B+ were recruited in 2:1 ratio, respectively, followed from birth to 18 months. Infants with low birth weight, premature birth, and congenital abnormalities were excluded. Anthropometrics were assessed at birth, 6 weeks, 3, 6, 12, and 18 months. Neurodevelopment assessments used the Bayley Scales of Infant and Toddler Development III from 6 weeks. Creatinine, alkaline phosphatase, and phosphorus were assessed at 3, 6, and 12 months.

RESULTS

Of 260 HIV-and-ARV-exposed and 125 HIV-and-ARV-unexposed infants enrolled at birth, 87% and 57%, 78% and 59%, 77% and 54%, 73% and 51%, and 65% and 43% completed 6-weeks, 3, 6, 12, and 18 months visits, respectively. There were no significant differences in the mean Z-scores for length-for-age, weight-for-age, weight-for-length, mid-upper arm circumference-for-age, and head circumference-for-age between groups except at 6-weeks for length-for-age. No bone fractures occurred. Neurodevelopment outcomes were similar between groups. Of creatinine, alkaline phosphatase, and serum phosphate measurements, 1.7%, 2.6%, and 3.3% reached any toxicity levels grades 1-4, respectively, with no differences between groups.

CONCLUSION

Long-term exposure to EFV and TDF through breastfeeding in infants of HIV-infected mothers does not seem to result in significant growth, neurodevelopment, renal, or bone adverse outcomes. Data support safety of breastfeeding through 18 months within the Option B+ program.

Neonatal neurological examination in a resource-limited setting: What defines normal?

OBJECTIVE

To describe the results of the Hammersmith Neonatal Neurological Examination (HNNE) in a low-risk, term-born, contemporary sample in Ghana. Of particular interest was to compare these findings with the original British study that validated the HNNE, and published data from other low- and middle-income countries.

STUDY DESIGN

In a nested substudy of a larger prospective study (IMPRINT: Impact of Malaria in Pregnancy on Infant Neurodevelopment), 140 low-risk, term-born neonates (39.3 ± 1.4 weeks gestation) at Korle Bu Teaching Hospital in Accra, Ghana were administered the 34-item HNNE from birth to 48 h of age by trained physicians. Neonates' performance was compared with previously published normative data from the United Kingdom (1998), and published data from Thailand, Myanmar, Vietnam, and Uganda.

RESULTS

Ghanaian neonates demonstrated lower scores on 29/34 HNNE items relative to normative data from the United Kingdom (P < .05), with only 5% of Ghanaian neonates in our sample classified as neurologically optimal. There were significant differences in the proportion of neonates scoring optimally per HNNE item between our Ghanaian sample, compared with published data from other settings (Thai [13/16 items], Burmese [14/16 items], Vietnamese [7/9 items], and Ugandan [22/34 items] neonates). Raw scores were markedly different between Ghanaian and British neonates, with Ghanaian neonates demonstrating lower median and wider range of scores. These differences were less prominent between Ghanaian and Ugandan neonates.

CONCLUSION

Our findings raise questions as to whether or not the thresholds for optimality for the HNNE based on data from the United Kingdom are applicable to Ghanaian newborns. Our study could not fully resolve whether the differences in scores were due to genetic differences in developmental pathways, the implementation of the assessment, or the characteristics of our sample. Low proportions of neonates scoring optimally from other low- and middle-income countries suggest the need for further research to determine the clinical utility of the HNNE in resource-limited settings, including the predictive value for neurodevelopment later in infancy.

The Predictive Value of Language Scales: Bayley Scales of Infant and Toddler Development Third Edition in Correlation With Korean Sequenced Language Scale for Infant

Objective

To compare the relationship of the Bayley Scales of Infant and Toddler Development 3rd Edition (K-BSID-III) language score and the Sequenced Language Scale for Infant (SELSI) score and evaluate the sensitivity and specificity of K-BSID-III language score and optimal cutoff value with receiver operator characteristic (ROC) curve analysis in infants and toddlers with delayed language development.

Methods

A total of 104 children with suspected language developmental delay were included in this retrospective study. Subjects were tested using the K-BSID-III and SELSI and subdivided into several groups according to the severity of language scores. ROC curve analysis was performed to assess K-BSID-III for delayed language development.

Results

Receptive and expressive language subscales of the K-BSID-III showed markedly significant correlation with the SELSI scores (p<0.001). ROC analysis showed an area under the curve of 0.877 (p<0.001) in SELSI receptive score and 0.935 (p<0.001) in SELSI expressive score. The optimal cutoff value where sensitivity of 85% and specificity of 81% were achieved with the K-BSID-III receptive score was 1.50 (between average and low average) in the SELSI receptive score. The optimal cutoff value where sensitivity of 96% and specificity of 82% were achieved with the K-BSID-III expressive score was also 1.50 in the SELSI expressive score.

Conclusion

In this study, the correlations between K-BSID-III and SELSI language scores were statistically significant. However, the interpretation should be considered carefully in low average group due to tendency of underestimation of delayed language development.

Nutrition, growth, and other factors associated with early cognitive and motor development in Sub-Saharan Africa: a scoping review

BACKGROUND

Food insecurity, poverty and exposure to infectious disease are well-established drivers of malnutrition in children in Sub-Saharan Africa. Early development of cognitive and motor skills - the foundations for learning - may also be compromised by the same or additional factors that restrict physical growth. However, little is known about factors associated with early child development in this region, which limits the scope to intervene effectively. To address this knowledge gap, we compared studies that have examined factors associated with early cognitive and/or motor development within this population.

METHODS

Predetermined criteria were used to examine four publication databases (PsycInfo, Embase, Web of Science and Medline) and identify studies considering the determinants of cognitive and motor development in children aged 0-8 years in Sub-Saharan Africa.

RESULTS

In total, 51 quantitative studies met the inclusion criteria, reporting on 30% of countries across the region. Within these papers, factors associated with early child development were grouped into five themes: Nutrition, Growth and Anthropometry, Maternal Health, Malaria and HIV, and Household. Food security and dietary diversity were associated with positive developmental outcomes, whereas exposure to HIV, malaria, poor maternal mental health, poor sanitation, maternal alcohol abuse and stunting were indicators of poor cognitive and motor development.

DISCUSSION

In this synthesis of research findings obtained across Sub-Saharan Africa, factors that restrict physical growth are also shown to hinder the development of early cognitive and motor skills, although additional factors also influence early developmental outcomes. The study also reviews the methodological limitations of conducting research using Western methods in sub-Saharan Africa.

The effect of HIV infection and exposure on cognitive development in the first two years of life in Malawi

OBJECTIVES

To assess longitudinal patterns and determinants of cognitive development in infants living with HIV, infants exposed to maternal HIV infection, and HIV-unexposed infants.

METHODS

Prospective, community-based cohort study of 555 Malawian infants aged 8 weeks to 24 months, using multivariable linear mixed-effects regression models with random intercepts to analyze repeated measures of cognitive function.

RESULTS

At 3 months of age, cognitive scores on the Bayley Scales of Infant Development (BSID 3rd edition) were lower in the 96 HIV-infected infants (mean = 14.1 (SD:4.8)) compared to the 289 HIV-exposed (mean = 16.5 (SD:3.7)) and the 170 unexposed infants (mean = 17.5 (SD:3.3)). Over the first two years of life, the small deficit in cognitive development of infants living with HIV who survived and remained in care did not increase (mean score 52.9 among HIV-infected vs 55.6 among HIV unexposed). In multivariable analysis, malnutrition and a more advanced clinical infant HIV stage had a negative impact on cognition at age 3, while financial security, care by the biological mother, and ART for mother and child were associated with better cognitive status at this young age. The positive influence of maternal ART reversed with age.

CONCLUSIONS

Malawian infants exposed to HIV had a cognitive development that was similar to their unexposed peers in the first two years of life, while that of HIV infected infants lagged behind from the start. Early initiation of effective ART in all HIV infected mothers and infants, and prevention of infant malnutrition are important to safeguard cognitive development of children affected by HIV.

Neurodevelopmental and behavioural outcomes of HIV-exposed uninfected and HIV-unexposed children at 2-3 years of age in Cape Town, South Africa

Successful vertical HIV transmission prevention programmes (VTP) have resulted in an expanding population of HIV-exposed uninfected (HEU) infants whose growth, health and neurodevelopmental outcomes could have consequences for future resource allocation. We compared neurodevelopmental and behavioural outcomes in a prospective cohort of 2-3 year old HEU and HIV-unexposed uninfected (HU) children.Women living with and without HIV and their infants were enrolled within three days of birth from a low-risk midwife obstetric unit in Cape Town, South Africa during 2012 and 2013, under WHO Option A VTP guidelines. HIV-uninfected children aged 30-42 months were assessed using the Bayley scales of Infant Development-Third edition (BSID) and Strengths and Difficulties questionnaire (SDQ).Thirty-two HEU and 27 HU children (mean birth weight 3048g vs 3096g) were assessed. HEU children performed as well as HU children on BSID cognitive, language and motor domains. Mean scores fell within the low average range. Mothers of HEU children reported fewer conduct problems but stunting was associated with increased total difficulties on the SDQ.HEU and HU children's performance on the BSID was similar. In this low-risk cohort, HIV exposure did not confer additional risk. Stunting was associated with increased behavioural problems irrespective of HIV exposure.

Nutritional, Socioeconomic, and Delivery Characteristics Are Associated with Neurodevelopment in Tanzanian Children

OBJECTIVES

To evaluate the hypothesis that various maternal, socioeconomic, delivery, and infant nutritional characteristics are associated with early childhood development in young Tanzanian children.

STUDY DESIGN

We performed a prospective cohort study among 206 HIV-exposed, uninfected and 247 HIV-unexposed Tanzanian infants who had been enrolled in 2 separate micronutrient trials (NCT00197730 and NCT00421668). Trained nurses administered culturally modified Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III), to evaluate cognitive, motor, and language development at 15 months of age. This analysis explored predictors of BSID-III z-scores using multivariable linear regression.

RESULTS

Among maternal determinants, we found that low maternal height predicted all BSID-III domains in HIV-unexposed children; low maternal education predicted lower cognitive (standardized mean difference, -0.41; 95% CI, -0.74 to -0.08) and lower gross motor scores (standardized mean difference, -0.32; 95% CI, -0.61 to -0.04) in HIV-exposed children. Among delivery characteristics, facility delivery predicted higher cognitive scores (standardized mean difference, 1.36; 95% CI, 0.26-2.46); and oxytocin administration predicted lower fine motor scores (standardized mean difference, -0.48; 95% CI, -0.87 to -0.09) in HIV-exposed children. Higher length-for-age z-scores at 6 weeks of age predicted better cognitive (standardized mean difference, 0.15; 95% CI, 0.01-0.29) and expressive language scores (standardized mean difference, 0.16; 95% CI, 0.02-0.29) at 15 months in HIV-exposed infants.

CONCLUSIONS

This hypothesis-generating study found significant associations between nutritional status and health of the mother and child, and maternal educational attainment, with direct measures of early childhood development at 15 months of age. In addition, several aspects of delivery (facility birth and oxytocin administration) were associated with early childhood development. Future intervention trials should focus on modifiable maternal, infant, and obstetric factors to strengthen the evidence base concerning early childhood development.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00197730 and NCT00421668.

The reliability and validity of Bayley-III cognitive scale in China's male and female children

BACKGROUND

Since publication in 2006, the Bayley-III scale has been used widely in pediatric populations worldwide; however, there have been very few studies which examined the usefulness and the potential sex differences in a Chinese context.

AIMS

To assess the reliability and validity of the Bayley-III cognitive scale, and detect possible sex differences in term children so as to provide evidence for clinical and research use in China.

STUDY DESIGN

Cross-sectional study PARTICIPANTS AND OUTCOME MEASURES: Of the 1589 children from 3 healthcare institutions that were initially recruited, a total of 1444 children were included in the final analysis. We randomly selected 5-10% children from the total sample to evaluate the test-retest, inter-rater and criteria-related reliability in order to meet the psychometric criteria of Bayley-III scale. Inter-item consistency, test-retest and inter-rater reliability of the scale were estimated using Split-half method and Intra-class Correlation Coefficient (ICC). The content validity was evaluated by the Item-level Content Validity Index (I-CVI). The Mann-Kendall trend test was performed to assess trends of cognitive development, and post-hos Least Significant Difference test was used to detect age-appropriateness of items.

RESULTS

Six developmental pediatricians were trained to administer the Bayley-III cognitive scale. Inter-item consistency (n = 1444) with Guttman split-half coefficient was above 0.8, while test-retest (n = 144) and inter-rater reliability (n = 74) had good to excellent ICCs of over 0.9. The criteria-related validity (n = 74) of Bayley-III was acceptable, and associations with Gesell Developmental Schedules (GDS) were mainly above 0.8. The raw score of Bayley-III scale in total subjects (n = 1444) showed an increased trend across all months of age (p < 0.05), and only the score in age group of 35M16D to 36M15D declined in females (p < 0.05, n = 722). Female children presented a higher score than male children in all subjects and in the 18-23 months age group (p < 0.05).

CONCLUSIONS

Our findings provide important evidence that the Bayley-III cognitive scale is a valid measurement which could be used in Chinese population, as well as the consideration of sex differences when used in a Chinese context.

The Impact of Norms on the Outcome of Children Born Very-Preterm when Using the Bayley-III: Differences between US and German Norms

BACKGROUND

The Bayley Scales of Infant and Toddler Development, third edition (Bayley-III) are widely used to assess the development of children born preterm. However, it is still unclear whether US norms are adequate for use in other populations. In 2014, the German version of the Bayley-III with German norms was published.

OBJECTIVES

We aimed to compare the performance of very-preterm infants at one, two, and three years of age using the German versus US norms of the Bayley-III.

METHODS

All children born prior to 32 weeks of gestational age during 2012 and 2015 and taking part in the follow-up program of the Medical University of Vienna were assessed and scored according to both German and US norms by two expert clinical psychologists at the age of one, two, and three years of age.

RESULTS

In total, 843 tests were obtained from 450 children. When looking at scaled scores for cognitive, language, and motor outcomes, preterm children achieved significantly lower scores in nearly all subtests with the German as compared to the US norms. In addition, the proportion of impaired children scoring < 1 standard deviation (SD) and < 2 SD below the norm was significantly higher in nearly all subtests when using the German compared to the US norms (p < 0.05).

CONCLUSIONS

Applying German and US norms of the Bayley-III leads to different outcomes in very-preterm children, and these differences are statistically significant and clinically relevant. Thus, comparisons of outcomes of very-preterm children using culturally specific norms are problematic, and these findings have to be considered.

Varieties of Young Children's Prosocial Behavior in Zambia: The Role of Cognitive Ability, Wealth, and Inequality Beliefs

By the 3rd year of life, young children engage in a variety of prosocial behaviors, including helping others attain their goals (instrumental helping), responding to others' emotional needs (comforting), and sharing resources (costly giving). Recent work suggests that these behaviors emerge early, during the first 2 years of life (Svetlova et al., 2010; Thompson and Newton, 2012; Dunfield and Kuhlmeier, 2013). To date, however, work investigating early varieties of prosocial behavior has largely focused on Western samples and has not assessed the impact of poverty and inequality. In this work, we investigate prosocial behavior in 3-year-olds in Zambia, a lower-middle income country with high wealth inequality. Experiments were integrated into a larger public health study along with both objective and subjective (parent) measures of wealth and inequality. Three-hundred-seventy-seven children (Mean age = 36.77 months; SD = 2.26 months) were presented with an instrumental helping task, comforting task, and two steps of a giving task - one with higher cost (children could give away their only resource) and one with lower cost (children had three resources to give). As predicted, rates of prosociality varied hierarchically by the cost of the action: instrumental helping was the most common followed by comforting, lower cost giving, and higher cost giving. All prosocial behaviors were significantly correlated with one another (with the exception of high cost giving), and with general cognitive ability. Objective family wealth did not predict any of the child's prosocial behaviors. However, subjective beliefs showed that mothers who believed that they had more than others in their village had children who were more likely to engage in instrumental helping, and mothers who believed that village inequality was a problem had children who were more likely to engage in low cost giving. Low cost giving was also more likely for children whose parents reported reading storybooks to them. This suggests that costly giving in the context of pretend play may relate to children's experience with using stories as representations of real life events. The results suggest both cultural differences and universalities in the development of prosociality and point to environmental factors that influence prosociality.

Validity and cross-cultural differences of the Bayley Scales of Infant and Toddler Development, Third Edition in typically developing infants

BACKGROUND

The Dutch translation of Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III-NL) is a comprehensive tool assessing cognitive, language and motor development in children up to 42 months.

AIMS

The first aim of this study was to evaluate concurrent validity of the Bayley-III-NL Gross Motor Scale (GMS) in relation to the Alberta Infant Motor Scale (AIMS). Secondly, divergent validity between the other subscales mutually and the AIMS was investigated. Finally, the importance of population-specific reference values was examined.

METHODS AND PROCEDURES

A sample of 122 healthy, typically developing Flemish children (mean age: 9 months 7 days), born full term was assessed with the Bayley-III-NL and the AIMS.

OUTCOMES AND RESULTS

Concurrent validity of the Bayley-III-NL GMS and the AIMS was moderate to high (0.59-0.98; p < 0.001). In addition, weak correlations (-0.10-0.27) between the non-motor-Bayley-III-NL subscales and the AIMS were found. Finally, significant differences were found between Bayley-III scores based on Flemish and American norms (p < 0.001), except for fine motor skills (p = 0.11).

CONCLUSIONS AND IMPLICATIONS

This study provides support for the concurrent validity of the Bayley-III-NL GMS and divergent validity of the different Bayley-III-NL subscales. Secondly, population-specific reference values should be used to avoid over- and under estimation of infant's development.

Acceptability and Reliability of the Bayley Scales of Infant and Toddler Development-III Among Children in Bhaktapur, Nepal

Background: The Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) is the most widely used developmental assessment tool for infants and toddlers worldwide, but less is known about its psychometric properties and feasibility in low and middle-income countries. Aim: To assess the psychometric properties and feasibility of the Bayley-III when used in a large scale randomized controlled intervention trial in Nepal. Methods: The participating infants were part of a randomized, doubled blind, placebo-controlled trial to measure the efficacy of vitamin B12 supplementation on growth and neurodevelopment. A total of 600 children aged 6-11 months were enrolled and included for developmental assessment. The Bayley-III measures child development across five domains: cognition, receptive and expressive language, fine and gross motor skills. Some items were culturally adapted. To measure and ensure appropriate inter-observer agreement, standardization exercises were performed during the initial training, and double scoring of 7% of test sessions were conducted throughout the study by two examiners. Results: The inter-rater agreement was excellent for both the standardization exercises before the start of the study, and for the quality control throughout the study with intraclass correlation coefficient ranging from 0.95 to 0.99. The internal consistency measured by the Cronbach's alpha coefficient ranged between 0.57 and 0.87. The subtests raw scores as well as scaled scores were significantly correlated (p < 0.001). The means and SDs of the scaled scores compared with American norms were similar to the distribution in the American sample, with the exception of the receptive (Mean = 7.7, SD = 2.2) and expressive (Mean = 7.3, SD = 1.9) language subtests that were lower than the American norms. Conclusion: The inter-rater reliability between the scorers on the Bayley-III was excellent both during standardization and for the quality control. The distributions for the cognitive and motor subscales are comparable to the American norms, while caution is needed in the interpretation of the language scales. The results suggest that Bayley-III is a feasible tool for the assessment of neurodevelopmental status in nutritional studies in low resource settings such as Nepal. Cultural adaptations, training and standardization are prerequisites for a valid and reliable assessment using the Bayley-III.

Prenatal Mancozeb Exposure, Excess Manganese, and Neurodevelopment at 1 Year of Age in the Infants' Environmental Health (ISA) Study

BACKGROUND

Although growing evidence suggests that early-life excess manganese (Mn) impairs neurodevelopment, data on the neurodevelopmental effects of mancozeb, a fungicide containing Mn, and its main metabolite ethylenethiourea (ETU) are limited.

OBJECTIVE

We examined whether prenatal mancozeb exposure and excess Mn were associated with neurodevelopment in 355 1-y-old infants living near banana plantations with frequent aerial mancozeb spraying in Costa Rica.

METHODS

We measured urinary ETU, hair Mn, and blood Mn concentrations in samples collected 1-3 times during pregnancy from mothers enrolled in the Infants' Environmental Health (ISA) study. We then assessed neurodevelopment in their 1-y-old infants using the Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III). We estimated exposure-outcome associations using linear regression models adjusted for maternal education, parity, gestational age at birth, child age, Home Observation for Measurement of the Environment score, and location of neurodevelopmental assessment.

RESULTS

Median (P25-P75) urinary ETU, hair Mn, and blood Mn measured during pregnancy were 3.3 μg/L (2.4-4.9; specific gravity-corrected), 1.7 μg/g (0.9-4.1), and 24.0 μg/L (20.3-28.0), respectively. Among girls, higher ETU was associated with lower social-emotional scores [β per 10-fold increase=-7.4 points (95% CI: -15.2, 0.4)], whereas higher hair Mn was associated with lower cognitive scores [-3.0 (-6.1, 0.1)]. Among boys, higher hair Mn was associated with lower social-emotional scores [-4.6 (-8.5, -0.8)]. We observed null associations for blood Mn, language, and motor outcomes.

CONCLUSIONS

Our findings indicate that maternal exposure to mancozeb and excess Mn during pregnancy may have adverse and sex-specific effects on infant neurodevelopment. https://doi.org/10.1289/EHP1955.

Association between maternal exposure to phthalates and lower language ability in offspring derived from hair metabolome analysis

The fetus undergoes a crucial period of neurodevelopment in utero. The maternal hair metabolome provides an integrated record of the metabolic state of the mother prior to, and during pregnancy. We investigated whether variation in the maternal hair metabolome was associated with neurodevelopmental differences across infants. Maternal hair samples and infant neurocognitive assessments (using the Bayley III Scales of Infant Development at 24 months) were obtained for 373 infant-mother dyads between 26–28 weeks’ gestation from the Growing Up in Singapore Towards Healthy Outcomes cohort. The hair metabolome was analysed using gas chromatography-mass spectrometry. Intensity measurements were obtained for 276 compounds. After controlling for maternal education, ethnicity, and infant sex, associations between metabolites and expressive language skills were detected, but not for receptive language, cognitive or motor skills. The results confirm previous research associating higher levels of phthalates with lower language ability. In addition, scores were positively associated with a cluster of compounds, including adipic acid and medium-chain fatty acids. The data support associations between the maternal hair metabolome and neurodevelopmental processes of the fetus. The association between phthalates and lower language ability highlights a modifiable risk factor that warrants further investigation.

Establishing Bayley-III cut-off scores at 21 months for predicting low IQ scores at 3 years of age in a preterm cohort

Objective

To evaluate predictive validity and establish cut-off scores on the Bayley-III at age 21 months that best predict Intelligence Quotient (IQ) scores <70 or <80) at 3 years in a high-risk preterm cohort.

Method

Bayley-III evaluations at 21 months corrected age and intellectual assessments, primarily with the WPPSI-III, at 3 years corrected age were conducted with 520 infants born less than 29 weeks gestational age or less than 1250 g birth weight. Receiver Operator Characteristic (ROC) curves were used to establish Bayley-III Cognitive Composite cut-off scores that maximized Sensitivity and Specificity in predicting low IQ. Similar analyses were performed using the Language Composite, and a research derived mean Cognitive-Language Composite.

Results

A regression model for the association between 21-month Bayley-III Cognitive Composite and 3-year IQ scores was significant (P<0.0001, Adjusted R²=0.36). The ROC area under the Curve was 0.90 for the Cognitive Composite predicting IQ<70. The cut-off score that maximized Sensitivity and Specificity for predicting 3-year IQ<70 was a Cognitive Composite of <80. The ROC Area under the Curve was 0.80 for Cognitive Composites predicting IQ<80 and a Cognitive Composite cut-off score of <90 maximized Sensitivity and Specificity.

Conclusion

In this high-risk preterm cohort, there was a strong association between the Bayley-III Cognitive Composite at 21 months and IQ at 3 years. A Cognitive Composite cut-off score of <80 optimized classification of IQ<70 at 3 years, and a Cognitive Composite cut-off score of <90 optimized classification of IQ<80.

Nutrition, hygiene, and stimulation education to improve growth, cognitive, language, and motor development among infants in Uganda: A cluster-randomized trial

Stunting is associated with impaired cognitive and motor function. The effect of an education intervention including nutrition, stimulation, sanitation, and hygiene on child growth and cognitive/language/motor development, delivered to impoverished mothers in Uganda, was assessed. In a community-based, open cluster-randomized trial, 511 mother/children dyads aged 6-8 months were enrolled to an intervention (n = 263) or control (n = 248) group. The primary outcome was change in length-for-age z-score at age 20-24 months. Secondary outcomes included anthropometry and scores on the 2 developmental scales: Bayley Scales of Infant and Toddler Development-III and the Ages and Stages Questionnaire. There was no evidence of a difference in mean length-for-age z-score at 20-24 months between the 2 study groups: 0.10, 95% CI [-0.17, 0.36], p = .49. The intervention group had higher mean composite development scores than the controls on Bayley Scales of Infant and Toddler Development-III, the mean difference being 15.6, 95% CI [10.9, 20.2], p = .0001; 9.9, 95% CI [6.4, 13.2], p = .0001; and 14.6, 95% CI [10.9, 18.2], p = .0001, for cognitive, language, and motor composite scores, respectively. The mean difference in scores from the Ages and Stages Questionnaire were 7.0, 95% CI [2.9, 11.3], p = .001; 5.9, 95% CI [1.2, 10.3], p = .01; 4.2, 95% CI [1.7, 6.7], p = .001; 8.9, 95% CI [5.3, 12.3], p = .0001; and 4.4, 95% CI [0.0, 8.8], p = .05, for communication, gross motor, fine motor, problem solving, and personal-social development, respectively. The intervention education delivered to mothers promoted early development domains in cognitive, language, and motor development but not linear growth of small children in impoverished rural communities in Uganda. Our study showed that child development may be improved with a relatively low cost intervention strategy. This trial was registered at ClinicalTrials.gov as NCT02098031.

Developmental outcomes of an individualised complementary feeding intervention for stunted children: a substudy from a larger randomised controlled trial in Guatemala

OBJECTIVE

Stunting is a common cause of early child developmental delay; Guatemala has the fourth highest rate of stunting globally. The goal of this study was to examine the impact of an intensive community health worker-led complementary feeding intervention on early child development in Guatemala. We hypothesised that the intervention would improve child development over usual care.

DESIGN

A substudy from a larger individually randomised (1:1 allocation ratio), parallel-group superiority trial, with blinding of study staff collecting outcomes data.

SETTING

Rural, indigenous Maya communities in Guatemala.

PARTICIPANTS

210 stunted children (height-for-age z-score ≤-2.5) aged 6-24 months, previously randomised to usual care (106) or an intensive complementary feeding intervention (104). 84 in the intervention and 91 in the usual care arm agreed to participate.

INTERVENTIONS

Community health workers conducted monthly home visits for 6 months, providing usual care or individualised complementary feeding education.

MAIN OUTCOME MEASURES

The primary outcomes were change in z-scores for the subscales of the Bayley Scales of Infant Development (BSID), Third Edition.

RESULTS

100 individuals were included in the final analysis, 47 in the intervention and 53 in the usual care arm. No statistically significant differences in age-adjusted scores between the arms were observed for any subscale. However, improvements within-subjects in both arms were observed (median duration between measurements 189 days (IQR 182-189)). Mean change for subscales was 0.45 (95% CI 0.23 to 0.67) z-scores in the intervention, and 0.43 (95% CI 0.25 to 0.61) in the usual care arm.

CONCLUSIONS

An intensive complementary feeding intervention did not significantly improve developmental outcomes more than usual care in stunted, indigenous Guatemalan children. However, both interventions had significant positive impacts on developmental outcomes.

TRIAL REGISTRATION NUMBER

NCT02509936.

STAGE

Results.

Model Selection in Continuous Test Norming With GAMLSS

To compute norms from reference group test scores, continuous norming is preferred over traditional norming. A suitable continuous norming approach for continuous data is the use of the Box-Cox Power Exponential model, which is found in the generalized additive models for location, scale, and shape. Applying the Box-Cox Power Exponential model for test norming requires model selection, but it is unknown how well this can be done with an automatic selection procedure. In a simulation study, we compared the performance of two stepwise model selection procedures combined with four model-fit criteria (Akaike information criterion, Bayesian information criterion, generalized Akaike information criterion (3), cross-validation), varying data complexity, sampling design, and sample size in a fully crossed design. The new procedure combined with one of the generalized Akaike information criterion was the most efficient model selection procedure (i.e., required the smallest sample size). The advocated model selection procedure is illustrated with norming data of an intelligence test.

Maternal stress modifies the effect of exposure to lead during pregnancy and 24-month old children's neurodevelopment

BACKGROUND

Lead and psychosocial stress disrupt similar but not completely overlapping mechanisms. Exposure during the prenatal period to each of these insults singularly has been found to alter normal neurodevelopment; however, longitudinal associations with stress modifying the effect of lead have not been sufficiently analyzed in epidemiologic studies.

OBJECTIVE

To evaluate prenatal stress as an effect modifier of gestational lead neurotoxicity.

METHODS

We used a structural equations modeling approach with a trivariate response to evaluate cognitive, language and motor scores of the Bayley Scales of Infant Development-III in 24month-old children (n=360). Maternal blood lead levels were measured at the 2nd and 3rd trimester and psychosocial stress during pregnancy was assessed using a negative life events (NLE) scale derived from the CRYSIS questionnaire.

RESULTS

3rd trimester lead (mean 3.9±3.0 SDμg/dL) and stress (median=3 NLE) were negatively associated with Bayley III scores. Using the model's results we generated profiles for 0, 2, 4 and 6 NLE across lead levels (up to 10μg/dL) and observed a dose-response for the developmental scores when lead levels were below 2μg/dL. Each NLE curve had a different shape across increasing lead levels. Higher stress (NLE=6) resulted in lower cognitive scores for both sexes, in lower language scores in girls but not boys. In the absence of stress we saw a negative association with lead for all scores, however for language and motor scores, higher stress seemed to mask this association.

CONCLUSIONS

Our work examined and confirmed prenatal stress exposure as a modifier of the well-known neurotoxic effects of prenatal lead. It adds to the existing evidence pointing at the importance of studying the co-exposure of chemical and non-chemical exposures, specifically of considering the emotional environment of children at early developmental stages of life.

Cross-cultural validity of standardized motor development screening and assessment tools: a systematic review

AIM

To investigate whether standardized motor development screening and assessment tools that are used to evaluate motor abilities of children aged 0 to 2 years are valid in cultures other than those in which the normative sample was established.

METHOD

This was a systematic review in which six databases were searched. Studies were selected based on inclusion/exclusion criteria and appraised for evidence level and quality. Study variables were extracted.

RESULTS

Twenty-three studies representing six motor development screening and assessment tools in 16 cultural contexts met the inclusion criteria: Alberta Infant Motor Scale (n=7), Ages and Stages Questionnaire, 3rd edition (n=2), Bayley Scales of Infant and Toddler Development, 3rd edition (n=8), Denver Developmental Screening Test, 2nd edition (n=4), Harris Infant Neuromotor Test (n=1), and Peabody Developmental Motor Scales, 2nd edition (n=1). Thirteen studies found significant differences between the cultural context and normative sample. Two studies established reliability and/or validity of standardized motor development assessments in high-risk infants from different cultural contexts. Five studies established new population norms. Eight studies described the cross-cultural adaptation of a standardized motor development assessment.

INTERPRETATION

Standardized motor development assessments have limited validity in cultures other than that in which the normative sample was established. Their use can result in under- or over-referral for services.

Multivariable analysis to determine if HIV-1 Tat dicysteine motif is associated with neurodevelopmental delay in HIV-infected children in Malawi

Background

HIV-1 Tat protein is implicated in HIV-neuropathogenesis. Tat C31S polymorphism (Tat^CS) has been associated with milder neuropathology in vitro and in animal models but this has not been addressed in a cohort of HIV-infected adults or children.

Methods

HIV viral load (VL) in plasma and cerebrospinal fluid (CSF) were determined and plasma HIV tat gene was sequenced. Neurodevelopmental assessment was performed using Bayley Scales of Infant Development III (BSID-III), with scores standardized to Malawian norms. The association between Tat^CS and BSID-III scores was evaluated using multivariate linear regression.

Results

Neurodevelopmental assessment and HIV tat genotyping were available for 33 children. Mean age was 19.4 (SD 7.1) months, mean log VL was 5.9 copies/mL (SD 0.1) in plasma and 3.9 copies/mL (SD 0.9) in CSF. The prevalence of Tat^CC was 27 %. Z-scores for BSID-III subtests ranged from −1.3 to −3.9. Tat^CC was not associated with higher BSID-III z-scores.

Conclusions

The hypothesis of milder neuropathology in individuals infected with HIV Tat^CS was not confirmed in this small cohort of Malawian children. Future studies of tat genotype and neurocognitive disorder should be performed using larger sample sizes and investigate if this finding is due to differences in HIV neuropathogenesis between children and adults.

Validation and adaptation of rapid neurodevelopmental assessment instrument for infants in Guatemala

BACKGROUND

Timely detection of neurodevelopmental impairments in children can prompt referral for critical services that may prevent permanent disability. However, screening of impairments is a significant challenge in low-resource countries. We adapted and validated the rapid neurodevelopmental assessment (RNDA) instrument developed in Bangladesh to assess impairment in nine domains: primitive reflexes, gross and fine motor development, vision, hearing, speech, cognition, behaviour and seizures.

METHODS

We conducted a cross-sectional study of 77 infants (0-12 months) in rural Guatemala in July 2012 and July 2013. We assessed inter-rater reliability and predictive validity between the 27-item RNDA and the 325-item Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III) and concurrent validity based on chronic malnutrition, a condition associated with neurodevelopmental impairments. For both RNDA and BSID-III, standardized scores below 80 were defined as borderline impairment.

RESULTS

Children came from rural households (92%), were born to indigenous women of Mayan descent (73%) and had moderate or severe growth stunting (43%). Inter-rater reliability for eight RNDA domains was of moderate to high reliability (weighted κ coefficients, 0.49-0.99). Children screened positive for impairment in fine motor (17%) and gross motor (14%) domains using the RNDA. The RNDA had good concurrent ability; infants who were growth stunted had higher mean levels of impairment in gross motor, speech and cognition domains (all p < 0.001). The RNDA took 20-30 min to complete compared with 45-60 min for BSID-III.

CONCLUSIONS

Wide-scale implementation of a simple, valid and reliable screening tool like the RNDA by community health workers would facilitate early screening and referral of infants at-risk for neurodevelopmental impairment.