Predictors of motor developmental milestones during the first year of life

Do maternal and paternal education protect against developmental delays?

BACKGROUND

Parental education is linked to child development and wellbeing, but unique and combined contributions of maternal and paternal education have rarely been studied.

AIMS

This study assessed the individual and joint associations of maternal and paternal education on children's odds of a probable developmental delay.

METHODS AND PROCEDURES

Mothers (N = 3566) from the Upstate KIDS cohort study reported on theirs and the father's highest level of education and completed the Ages and Stages Questionnaires up to 7 times when the child was 4- to 36-months-old. A nonparametric constrained inference technique assessed the association between education and probable developmental delays.

OUTCOMES AND RESULTS

Higher levels of maternal and paternal education were protective against child probable developmental delays in years 2 (18, 24 months; p-trends<.001) and 3 (30, 36 months; p-trends<.001), but not year 1 (4, 8, 12 months; p-trend=.486-.832). Trends held adjusting for parental age and race. When adjusting for the other parent's education, only maternal education had unique associations with delays. Among parents with the same or similar education levels, when both parents had one level higher education it was also protective.

CONCLUSIONS AND IMPLICATIONS

Both maternal and paternal education may protect against children's developmental delays in toddlerhood, but maternal education may be particularly important.

Stimulating the motor development of very premature infants: effects of early crawling training on a mini-skateboard

Aim

To examine the effects of an early home-based 8-week crawling intervention performed by trained therapists on the motor and general development of very premature infants during the first year of life.

Methods

At term-equivalent age, immediately following discharge from the Neonatal Intensive Care Unit (NICU), we randomly allocated 44 premature infants born before 32 weeks' gestation without major brain damage to one of three conditions in our intervention study: crawling on a mini-skateboard, the Crawliskate (Crawli), prone positioning control (Mattress), or standard care (Control). The Crawli and Mattress groups received 5 min daily at-home training administered by trained therapists for 8 consecutive weeks upon discharge from the NICU. The outcomes of greatest interest included gross motor development (Bayley-III) at 2, 6, 9, and 12 months (primary outcome) corrected age (CA), mature crawling at 9 months CA and general development at 9 and 12 months CA [Ages and Stages Questionnaires-3 (ASQ-3)]. The study was registered at www.clinicaltrials.gov; registration number: NCT05278286.

Results

A 3 (Condition) × 4 (Age) repeated measures ANOVA revealed that Crawli group infants had significantly higher Bayley-III gross motor development scores than Mattress and Control group infants. Crawli group infants also scored significantly higher on groups of Bayley-III items related to specific motor skills than infants in the other groups, including crawling at 9 months CA. We found significant differences in favor of the Crawli group in separate one-way ANOVAs at each of the ages we examined. A 3 (Condition) × 2 (Age) repeated measures ANOVA revealed that the Crawli group scored significantly higher than the Control group for the ASQ-3 total score and communication score and significantly higher for the fine motor score than the Control and Mattress groups. We found additional significant differences in favor of the Crawli group for other dimensions of the ASQ-3 in separate one-way ANOVAs at 9 and 12 months CA.

Interpretation

Early crawling training on a Crawliskate provides an effective way to promote motor and general development in very premature infants. The findings also provide clear evidence for a link between newborn crawling and more mature crawling later in development.

Secular trends in early motor development between 1980 and 2010 in Japan

OBJECTIVE

Recent changes in birth characteristics in Japan may have a potential influence on children's developments. Therefore, we investigated secular trends in gross motor milestones.

DESIGN

Data were collected from an official Japanese nationwide serial cross-sectional survey conducted every 10 years since 1960. 22 320 participants aged 2-18 months were identified from the four surveys from 1980 to 2010.

OUTCOMES

We assessed whether or not a child achieved four gross motor milestones including rolling over (rolling), sitting without support (sitting), standing with support (standing) and walking alone (walking). The target age was defined as the age when the attainment rate ranged from >5% to >95% of the total. Multivariate logistic regression models were fitted.

RESULTS

The final cohort included 20 570 children. The target ages were determined as follows: 3-6 months for rolling; 5-9 months for sitting; 6-11 months for standing; and 9-15 months for walking. The attainment rates of sitting, standing and walking in 1990 were higher than those in 2010, even after adjusting for child characteristics (sitting: adjusted OR (aOR)=2.07 (95% CI 1.62 to 2.65); standing: aOR=1.63 (95% CI 1.32 to 2.02); and walking: aOR=1.61 (95% CI 1.34 to 1.95)).

CONCLUSIONS

The proportion of children who attained three motor milestones (sitting, standing and walking) by set target ages decreased between 1990 and 2010. The contribution of birth characteristics including a decrease in gestational age and fetal growth, as well as changes in other child characteristics, failed to explain why this decrease occurred.

Is Motor Milestone Assessment in Infancy Valid and Scaled Equally Across Sex, Birth Weight, and Gestational Age? Findings From the Millennium Cohort Study

Is the assessment of motor milestones valid and scaled equivalently for all infants? It is not only important to understand if the way we use gross and fine motor scores are appropriate for monitoring motor milestones but also to determine if these scores are confounded by specific infant characteristics. Therefore, the aim of the study is to investigate the latent structure underlying motor milestone assessment in infancy and measurement invariance across sex, birth weight, and gestational age. For this study, the birth cohort data from the United Kingdom Millennium Cohort Study (MCS) was used, which includes the assessment of eight motor milestone tasks from the Denver Developmental Screening Test in 9-month-old infants (N = 18,531), depicting early motor development of the first children of generation Z. Confirmatory factor analyses showed a better model fit for a two-factor structure (i.e., gross and fine motor development) compared to a one-factor structure (i.e., general motor development), and multiple indicators multiple causes modeling revealed no differential item functioning related to sex, birth weight, and gestational age. The study provides support for the use of gross and fine motor scores when assessing motor milestones in infants—both boys and girls with different birth weights and of varying gestational ages. Further investigation into widely adopted assessment tools is recommended to support the use of valid composite scores in early childhood research and practice.

Factors associated with gross motor development from birth to independent walking: A systematic review of longitudinal research

AIM

The aim of this study is to gain more insight into child and environmental factors that influence gross motor development (GMD) of healthy infants from birth until reaching the milestone of independent walking, based on longitudinal research.

BACKGROUND

A systematic search was conducted using Scopus, PsycINFO, MEDLINE and CINAHL to identify studies from inception to February 2020. Studies that investigated the association between child or environmental factors and infant GMD using longitudinal measurements of infant GMD were eligible. Two independent reviewers extracted key information and assessed risk of bias of the selected studies, using the Quality in Prognostic Studies tool (QUIPS). Strength of evidence (strong, moderate, limited, conflicting and no evidence) for the factors identified was described according to a previously established classification.

RESULTS

In 36 studies, six children and 11 environmental factors were identified. Five studies were categorized as having low risk of bias. Strong evidence was found for the association between birthweight and GMD in healthy full-term and preterm infants. Moderate evidence was found for associations between gestational age and GMD, and sleeping position and GMD. There was conflicting evidence for associations between twinning and GMD, and breastfeeding and GMD. No evidence was found for an association between maternal postpartum depression and GMD. Evidence for the association of other factors with GMD was classified as 'limited' because each of these factors was examined in only one longitudinal study.

CONCLUSION

Infant GMD appears associated with two child factors (birthweight and gestational age) and one environmental factor (sleeping position). For the other factors identified in this review, insufficient evidence for an association with GMD was found. For those factors that were examined in only one longitudinal study, and are therefore classified as having limited evidence, more research would be needed to reach a conclusion.

Delayed Motor Milestones Achievement in Infancy Associates with Perturbations of Amino Acids and Lipid Metabolic Pathways

The relationship between developmental milestone achievement in infancy and later cognitive function and mental health is well established, but underlying biochemical mechanisms are poorly described. Our study aims to discover pathways connected to motor milestone achievement during infancy by using untargeted plasma metabolomic profiles from 571 six-month-old children in connection with age of motor milestones achievement (Denver Developmental Index) in the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) mother–child cohort. We used univariate regression models and multivariate modelling (Partial Least Squares Discriminant Analysis: PLS-DA) to examine the associations and the VDAART (Vitamin D Antenatal Asthma Reduction Trial) cohort for validation. The univariate analyses showed 62 metabolites associated with gross-motor milestone achievement (p < 0.05) as well as the PLS-DA significantly differentiated between slow and fast milestone achievers (AUC = 0.87, p = 0.01). Higher levels of tyramine-O-sulfate in the tyrosine pathway were found in the late achievers in COPSAC (p = 0.0002) and in VDAART (p = 0.02). Furthermore, we observed that slow achievers were characterized by higher levels of fatty acids and products of fatty acids metabolism including acyl carnitines. Finally, we also observed changes in the lysine, histidine, glutamate, creatine and tryptophan pathways. Observing these metabolic changes in relation to gross-motor milestones in the first year of life, may be of importance for later cognitive function and mental health.

Predictors of early motor trajectories from birth to 5 years in neonatal at-risk and control children

AIM

To describe motor development in preschool children, to identify perinatal, neonatal and social environmental risk factors of poor motor development, and to replicate results in a second cohort.

METHODS

Two prospective samples in Germany (Bavarian Longitudinal Study, BLS) and Finland (Arvo Ylppö Longitudinal Study, AYLS) assessed 4741 and 1423 children from birth to 56 months, respectively. Motor functioning was evaluated at birth, and 5, 20 and 56 months. Perinatal, neonatal and social environmental information was collected at birth and 5 months.

RESULTS

Two distinct motor trajectories were identified: low (BLS: n = 4486 (94.6%), AYLS: n = 1391 (97.8%)) and high (BLS: n = 255 (5.4%), AYLS: n = 32 (2.2%)) degree of motor difficulties. High degree of motor difficulties was predicted by neonatal complications, abnormal neonatal neurological status, duration of hospitalisation and poor parent-infant relationships. Although neonatal complications and poor parent-infant relationships did not significantly predict high degree of motor difficulties in the AYLS, the trends identified were similar to those obtained from the BLS.

CONCLUSION

Early identification of children at-risk of motor difficulties across infancy and toddlerhood may help referring those children to interventions earlier. Modifiable risk factors, such as parent-infant relationships, may be addressed by intervention strategies to prevent children from developing motor difficulties.

Early life predictors of intelligence in young adulthood and middle age

BACKGROUND

Studies on early predictors of intelligence often focus on single or few predictors and often on childhood intelligence. This study compared the contributions of a broad selection of potential early predictors of intelligence at different adult ages.

METHODS

Information on predictors was recorded prospectively in the Copenhagen Perinatal Cohort during pregnancy, at delivery, and at 1- and 3-year examinations for children born between 1959-61. Adult intelligence was assessed at three independent follow-ups using three different tests of intelligence: Børge Priens Prøve, Wechsler Adult Intelligence Scale, and Intelligenz-Struktur-Test 2000R. From a total of 4697 cohort members, three non-overlapping samples were derived.

RESULTS

The included predictors explained between 22.2-24.3% of the variance in adult IQ, with parental socioeconomic status and sex explaining 16.2-17.0%. Other consistent predictors were head circumference at birth, increase in head circumference head during the first three years, and 3-year milestones. Head circumference was the most important anthropometric measure compared to measures of weight and length.

CONCLUSION

Besides social status and sex, the strongest and most consistent early predictors of adult intelligence were physical or behavioural characteristics that to some extent reflect brain-and cognitive development.

Predictors of early life milestones: Results from the Copenhagen Perinatal Cohort

Background

Pre- and postnatal factors have been found to be predictors of age at attaining milestones in infancy; however, the degree to which such factors are predictors of milestones in the subsequent years is less investigated. The aim was to conduct a systematic evaluation of a broad range of possible predictors of milestone attainment during the second and third years to identify factors that explain significant inter-individual variance.

Methods

Mothers of 4009 children from the Copenhagen Perinatal Cohort (1959–61) were interviewed by a physician about 20 developmental milestones at a three-year examination. Milestones were related to: Language, Walking, Eating, Dressing, Social interaction, and Toilet training. Information on possible predictors was collected during pregnancy and at a 1- and 3-year follow-up.

Results

Several pre- and postnatal factors were significantly associated with the timing of milestone attainment; especially parental social status, paternal age, sex, gestational age, birth weight, birth length, weight increase in the first year of life, and motor development during the first year of life. The significant predictors explained 16.2% of the variance in the Overall mean of milestones and 20.3% of the variance in milestones related to Walking. The most influential individual factor for the timing of milestone attainment was previous motor development during the first year of life. Additionally, sex was an important factor as girls were generally faster at attaining milestones. Parental social status was a consistent, but relatively week predictor.

Conclusion

A notable amount of variance in the timing of milestones during the first three years of life can be explained by perinatal and early postnatal factors. The study provides evidence of developmental continuity as the main predictor of milestones in the second and third years was the speed of development during the first year.

Developmental milestones and behavior of infant rats: The role of sensory input from whiskers

Developmental milestones are behavioral and physical skills which are considered as markers of neurodevelopment. In rodents, sensory input from whiskers plays a crucial role in development of brain functions. Development of whisker system in rats includes the early period of passive whisker touch (PN1-8) before the onset of coordinated whisker movements which underlie active sensing. Inasmuch as transitioning from passive to active sensing requires a strong sensorimotor integration, we assume that the effect of whisker deprivation during the period of passive touch is unfavorable for neurodevelopment, but deprivation after the onset of active sensing might elicit less harmful effect due to compensatory neuroplalstic changes. Here we examined the effect of complete whisker trimming (WT) in WAG/Rij rats during PN1-8 and PN9-16 (active sensing) on achieving developmental milestones (e.g., eyelid opening, walking, self-grooming, rearing activity, physical maturation of forelimbs), locomotor activity and body weight. Control groups underwent sham trimming during the same periods. WT during PN1-8 caused a delay in achieving all investigated milestones, but WT during PN9-16 delayed only self-grooming. Both WT/sham trimming during PN9-16 caused a delay in explorative behavior, but accelerated self-grooming. These changes are likely to link with the effect of manipulations during PN9-16 in previously unhandled pups, but not specifically with WT. In general, developmental milestones appeared to be an informative tool to access neurodevelopment in rat pups and might have a translational value for studying developmental disorders during early life.

A multivariate discrete failure time model for the analysis of infant motor development

We develop a multivariate discrete failure time model for the analysis of infant motor development. We use the model to jointly evaluate the time (in months) to achievement of three well-established motor milestones: sitting up, crawling, and walking. The model includes a subject-specific latent factor that reflects underlying heterogeneity in the population and accounts for within-subject dependence across the milestones. The factor loadings and covariate effects are allowed to vary flexibly across milestones, and the milestones are permitted to have unique at-risk intervals corresponding to different developmental windows. We adopt a Bayesian inferential approach and develop a convenient data-augmented Gibbs sampler for posterior computation. We conduct simulation studies to illustrate key features of the model and use the model to analyze data from the Nurture study, a birth cohort examining infant health and development during the first year of life.

Attainment of gross motor milestones by preterm children with normal development upon school entry

BACKGROUND

Little is known on the motor development of moderately preterm born (MPT) children, in comparison with early preterm born (EPT) children and fullterm born (FT), for children with normal motor outcomes at school entry.

AIMS

To compare attainment rates of gross motor milestones reached between ages 1-24 months for MPT, EPT, and FT children, all with normal development upon school entry.

STUDY DESIGN

Prospective cohort study.

SUBJECTS

We included 1247 preterm (PT) children (gestational age [GA] 24.0-35.6 weeks) and 488 FT children (GA 38.0-41.6 weeks), with normal gross motor development at 4 years according to the Ages and Stages Questionnaire.

OUTCOME MEASURES

We assessed 11 gross motor milestones assessed in preventive child healthcare during six standardized visits at calendar age.

RESULTS

During the first six months, all PT categories had lower milestone attainment-rates than FTs children (differences 9-60% for PTs compared with FTs children). For all PT categories attainment rates gradually increased during toddlerhood. For PT children with higher GA, differences in attainment rates compared with FTs children were smaller and attainment rates became comparable to FT children at an earlier age. At age 24 months only attainment rates for PT children born <30 weeks GA remained lower than for FTs children (85% versus 95%, P < 0.01).

CONCLUSION

Milestone attainment rates are highly dependent on GA during the first two years. Differences between PT and FT children are larger and persist longer with lower GA. For PT children <30 weeks GA, differences still occur at 24 months. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: controlled-trials.com, ISRCTN 80622320.

Articulation Speaks to Executive Function: An Investigation in 4- to 6-Year-Olds

Executive function (EF) and language learning play a prominent role in early childhood development. Empirical research continues to point to a concurrent relation between these two faculties. What has been given little attention, however, is the association between EF and speech articulation abilities in children. This study investigated this relation in children aged 4-6 years. Significant correlations indicated that children with better EF [via parental report of the Behavior Rating Inventory of Executive Function (BRIEF) inventory] exhibited stronger speech sound production abilities in the articulation of the "s" and "sh" sounds. Furthermore, regression analyses revealed that the Global Executive Composite (GEC) of EF as measured by the BRIEF, served as a predictor for speech sound proficiency and that speech sound proficiency served as a predictor for the GEC. Together, these results demonstrate the imbricated nature of EF and speech sound production while bearing theoretical and practical implications. From a theoretical standpoint, the close link between EF and speech articulation may indicate a common ontogenetic pathway. From a practical perspective, the results suggest that children with speech difficulties could be at higher risk for EF deficits.