Assessment of developmental coordination disorder in children born with extremely low birth weights

Predictive validity of the Developmental Coordination Disorder Questionnaire as a screening tool to identify motor skill problems: A systematic review and meta-analysis

BACKGROUND

The Developmental Coordination Disorder Questionnaire (DCDQ) has been used to screen children who probably have developmental coordination disorder (DCD).

AIMS

We systematically reviewed studies on the predictive validity of the DCDQ and performed a meta-analysis on its diagnostic accuracy.

METHODS AND PROCEDURES

Literature was searched through four electronic databases: MEDLINE, Embase, CINAHL, and PsycArticles. A total of 27 studies was selected based on the inclusion criteria. The sensitivity and specificity of the DCDQ were assessed using summary receiver operating characteristic (sROC) curves. Subgroup analyses were conducted according to the DCDQ type, reference standard, and participant type.

OUTCOMES AND RESULTS

Overall, the DCDQ has a sensitivity of 0.70 and a specificity of 0.77, showing moderate diagnostic accuracy (area under the curve, 0.80). Subgroup analysis showed that the revised version of the DCDQ had higher diagnostic accuracy than the original version. When the reference standard was the Diagnostic and Statistical Manual of Mental Disorders, the sensitivity and specificity of the DCDQ were 0.87 and 0.83, respectively. The diagnostic accuracy was higher in clinical samples compared to the general population.

CONCLUSIONS AND IMPLICATIONS

This study demonstrated that the DCDQ has adequate diagnostic accuracy, suggesting it can help screen children with motor skill deficits.

Advances in Genetics and Epigenetics of Developmental Coordination Disorder in Children

Developmental coordination disorder (DCD) is a developmental disorder characterized by impaired motor coordination, often co-occurring with attention deficit disorder, autism spectrum disorders, and other psychological and behavioural conditions. The aetiology of DCD is believed to involve brain changes and environmental factors, with genetics also playing a role in its pathogenesis. Recent research has identified several candidate genes and genetic factors associated with motor impairment, including deletions, copy number variations, single nucleotide polymorphisms, and epigenetic modifications. This review provides an overview of the current knowledge in genetic research on DCD, highlighting the importance of continued research into the underlying genetic mechanisms. While evidence suggests a genetic contribution to DCD, the evidence is still in its early stages, and much of the current evidence is based on studies of co-occurring conditions. Further research to better understand the genetic basis of DCD could have important implications for diagnosis, treatment, and our understanding of the condition's aetiology.

Risk factors for cerebral palsy and movement difficulties in 5-year-old children born extremely preterm

BACKGROUND

Motor impairment is common after extremely preterm (EPT, <28 weeks' gestational age (GA)) birth, with cerebral palsy (CP) affecting about 10% of children and non-CP movement difficulties (MD) up to 50%. This study investigated the sociodemographic, perinatal and neonatal risk factors for CP and non-CP MD.

METHODS

Data come from a European population-based cohort of children born EPT in 2011-2012 in 11 countries. We used multinomial logistic regression to assess risk factors for CP and non-CP MD (Movement Assessment Battery for Children - 2nd edition ≤5th percentile) compared to no MD (>15th percentile) among 5-year-old children.

RESULTS

Compared to children without MD (n = 366), young maternal age, male sex and bronchopulmonary dysplasia were similarly associated with CP (n = 100) and non-CP MD (n = 224) with relative risk ratios (RRR) ranging from 2.3 to 3.6. CP was strongly related to severe brain lesions (RRR >10), other neonatal morbidities, congenital anomalies and low Apgar score (RRR: 2.4-3.3), while non-CP MD was associated with primiparity, maternal education, small for GA (RRR: 1.6-2.6) and severe brain lesions, but at a much lower order of magnitude.

CONCLUSION

CP and non-CP MD have different risk factor profiles, with fewer clinical but more sociodemographic risk factors for non-CP MD.

IMPACT

Young maternal age, male sex and bronchopulmonary dysplasia similarly increased risks of both cerebral palsy and non-cerebral palsy movement difficulties. Cerebral palsy was strongly related to clinical risk factors including severe brain lesions and other neonatal morbidities, while non-cerebral palsy movement difficulties were more associated with sociodemographic risk factors. These results on the similarities and differences in risk profiles of children with cerebral palsy and non-cerebral palsy movement difficulties raise questions for etiological research and provide a basis for improving the identification of children who may benefit from follow-up and early intervention.

Movement Difficulties at Age Five Among Extremely Preterm Infants

BACKGROUND AND OBJECTIVES

Children born extremely preterm (EPT), <28 weeks' gestational age, face higher risks of movement difficulties than their term-born peers. Studies report varying prevalence estimates and prognostic factors identifying children who could benefit from early intervention are inconsistent. This study investigated the prevalence of movement difficulties in children born EPT and associated risk factors.

METHODS

Data come from a population-based EPT birth cohort in 2011 and 2012 in 11 European countries. Children without cerebral palsy were assessed at 5 years of age (N = 772) with the Movement Assessment Battery for Children-Second Edition, which classifies movement difficulties as none (>15th percentile), at risk (6th-15th percentile) and significant (≤5th percentile). Associations with sociodemographic, perinatal, and neonatal characteristics collected from obstetric and neonatal medical records and parental questionnaires were estimated using multinomial logistic regression.

RESULTS

We found 23.2% (n = 179) of children were at risk for movement difficulties and 31.7% (n = 244) had significant movement difficulties. Lower gestational age, severe brain lesions, and receipt of postnatal corticosteroids were associated with significant movement difficulties, whereas male sex and bronchopulmonary dysplasia were associated with being at risk and having significant movement difficulties. Children with younger, primiparous, less educated, and non-European-born mothers were more likely to have significant movement difficulties. Differences in prevalence between countries remained after population case-mix adjustments.

CONCLUSIONS

This study confirms a high prevalence of movement difficulties among EPT children without cerebral palsy, which are associated with perinatal and neonatal risk factors as well as sociodemographic characteristics and country.

The role of health at birth and parental investment in early child development: evidence from the French ELFE cohort

This paper combines a theoretical and an empirical approach to address how health at birth affects child development. Using a simple theoretical model in which parents invest in their children, we identify the mechanisms through which better health at birth can improve child development. We also emphasise how parental socioeconomic status can shape the effects of health at birth. We perform an empirical analysis on a French cohort of children born in 2011, using a unique dataset ELFE. We identify the effect of birth weight and gestational age on child development at 1 year. The results indicate that only gestational age positively affects early development. We find no empirical evidence for the existence of a severity effect, according to which the adverse effects of poor health at birth are higher for children in low-income families or with poorly educated mothers.

Bilateral Motor Responses to Transcranial Magnetic Stimulation in Preterm Children at 9 Years of Age

OBJECTIVE

This study was aimed to evaluate motor tracts integrity in nondisabled preterm-born (PT) children at 9 years of age.

METHODS

Overall, 18 PT and 13 term-born (T) children without motor disability were assessed by transcranial magnetic stimulation (TMS). Motor-evoked potentials (MEPs) were measured bilaterally from the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles. Muscle responses could be stimulated from all patients.

RESULTS

Overall, 83.3 and 23.1% of PT and T children, respectively, had mild clumsiness (p = 0.001). One PT and three T children had immediate bilateral responses in the upper extremities. Seven PT children had delayed ipsilateral APB responses after left and ten after right TMS. Three controls had delayed ipsilateral responses. Ipsilateral lower extremity responses were seen in one PT after right and two PT children and one T child after left TMS. The results did not correlate to groups, genders, clumsiness, or handedness.

CONCLUSION

Children of PT and T may have bilateral motor responses after TMS at 9 years of age. Ipsilateral conduction emerges immediately or more often slightly delayed and more frequently in upper than in lower extremities.

SIGNIFICANCE

Bilateral motor conduction reflects developmental and neurophysiological variability in children at 9 years of age. MEPs can be used as a measure of corticospinal tract integrity in PT children.

Early identification of children with/at risk of developmental coordination disorder: a scoping review

AIM

To summarize current evidence for early identification and motor-based intervention for children aged 5 years and younger with/at risk of developmental coordination disorder (DCD).

METHOD

Using scoping review methodology and after duplicates were removed, 11 115 peer-reviewed articles and grey literature were independently screened by two authors. Data from 103 included records were extracted and synthesized by both assessors. One author entered the relevant data into tables, while the other author double-checked the entries.

RESULTS

Records included peer-reviewed studies, guidelines, conference presentations, and theses/dissertations. Most literature pertained to early identification (n=78), with fewer studies targeting intervention (n=22) or covering both topics (n=3). Literature was summarized in two main categories: (1) assessments for diagnostic criteria A and B; and (2) motor-based interventions for young children with/at risk of DCD. This article highlights the findings related to assessments, while a companion article summarizes the intervention literature.

INTERPRETATION

Emerging evidence shows that children, especially those at greatest risk of DCD, may be identified before formal school entry. Earlier identification will allow for earlier intervention, which may help to improve the developmental trajectories of children with/at risk of DCD and prevent secondary consequences of the disorder. It is recommended that health care providers explicitly use the term 'at risk of DCD'.

Risk factors in early life for developmental coordination disorder: a scoping review

AIM

To perform a scoping literature review of associations between risk factors in early life and developmental coordination disorder (DCD).

METHOD

PubMed, Embase, CINAHL, PsycINFO, and Web of Science (January 1994-March 2019) were searched to identify studies on early risk factors and motor impairment or DCD. The effect of single and multiple risk factors was assessed. Level of evidence was evaluated following the Centre for Evidence-Based Medicine guidelines. Meta-analysis on the effect of preterm birth was performed.

RESULTS

Thirty-six studies fulfilled inclusion criteria; 35 had evidence level 3, one had level 4. Highest evidence was available that preterm birth and male sex in term-born children were associated with DCD. The odds ratio of preterm birth was 2.02 (95% confidence interval: 1.43-2.85). Low to moderate evidence was available that parental subfertility, maternal smoking during pregnancy, postnatal corticosteroid treatment in infants born preterm, extra corporeal membrane oxygenation, retinopathy of prematurity, abnormalities on magnetic resonance imaging scans at term age, and accumulating perinatal or neonatal risk factors were associated with motor impairment.

INTERPRETATION

Limited information on early risk factors of DCD is available. Only preterm birth and male sex were consistently associated with an increased risk of DCD.

WHAT THIS PAPER ADDS

Preterm birth is a risk factor for developmental coordination disorder (DCD). In term-born children, male sex was consistently associated with DCD. Risk factors for DCD are similar to risk factors for cerebral palsy.

Long-term motor outcomes of very preterm and/or very low birth weight individuals without cerebral palsy: A review of the current evidence

We reviewed literature on long-term motor outcomes of individuals aged five years or older born very preterm (VP: ≤32 weeks of gestation) or with very low birth weight (VLBW: ≤1500g), without cerebral palsy (CP). PubMed produced 2827 articles, whereof 38 were eligible. Assessed by standardised and norm-based motor tests, the Movement Assessment Battery for Children being the most widely used, VP/VLBW individuals showed poorer motor skills compared with term-born controls with differences of approximately 1 SD in magnitude. Some studies assessed subdomains and differences were present in fine motor/manual dexterity, ball skills and gross motor/balance. Prevalence of motor problems varied largely from 8-37% in studies with cut-off at the 5th percentile or -1.5 SD to 12-71% in studies with cut-off at the 15th percentile or -1 SD. This review shows that the degree of motor impairments continues to be substantial among VP/VLBW individuals who do not develop CP.

Developmental Coordination Disorder: The Importance of Grounded Assessments and Interventions

This focused review is based on earlier studies which have shown that both children and adults diagnosed as having developmental coordination disorder (DCD), benefited from sensorimotor therapy according to the method Retraining for Balance (RB). Different approaches and assessments for children and adults in regard to DCD are scrutinized and discussed in comparison to RB which mainly includes (a) vestibular assessment and stimulation (b) assessment and integration of aberrant primary reflexes and (c) assessment and stimulation of auditory and visual perception. Earlier results indicate that the process of Sensorimotor therapy using RB techniques could be described according to a conceptual Kinesthetic-Vestibular Developmental Model (KVDM) whereby the training elicited temporary physical and psychological regressions followed by transformations i.e., positive physical and psychological development. We have also seen that this recurring pattern is similar for children and adults. In our conceptual model vestibular stimulation (perceptual priming) stimulates the nervous system, which might enhance object-related priming. This perceptual priming will also assist the suppression of persistent aberrant primary reflexes. In order to develop effective methods for assessment and intervention of DCD over the life span the importance of primary reflex inhibition and vestibular stimulation as well as a combination of bottom-up and top-down approaches have to be considered.

What Are We Measuring as Outcome? Looking Beyond Neurodevelopmental Impairment

Outcomes of neonatal intensive care unit (NICU) graduates have been categorized by rates of neurodevelopmental impairment at 2 years old. Although useful as metrics for research, these early childhood assessments may underestimate or overestimate later functional capabilities. Often overlooked are less severe but more prevalent neurobehavioral dysfunctions seen later in childhood, and chronic health concerns that may impact the child's quality of life (QoL). Comprehensive NICU follow-up should include measures of less severe cognitive/learning delays, physical/mental well-being, and the promotion of resilience in children and families. Studies are needed to identify QoL measures that will optimize children's assessments and outcomes.

The Impact of Bronchopulmonary Dysplasia on Childhood Outcomes

The rate of bronchopulmonary dysplasia (BPD) in preterm infants is increasing; this trend reflects, in part, improved survival among extremely premature infants. BPD is associated with adverse developmental and medical outcomes in early childhood and at least through school age. Therefore, BPD imposes a significant burden on infants and children, their families, and society. Many interventions to decrease BPD and the sequelae of BPD have been studied; few to date have been proved to decrease both BPD and later disability.

Developmental Coordination Disorder and Its Association With Developmental Comorbidities at 6.5 Years in Apparently Healthy Children Born Extremely Preterm

IMPORTANCE

There are concerns that apparently healthy extremely preterm children face a risk of developing motor impairments, such as developmental coordination disorder.

OBJECTIVE

To evaluate the prevalence of developmental coordination disorder and associated comorbidities in a national cohort of apparently healthy children born at 22 to 26 gestational weeks, compared alongside term-born peers.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, population-based cohort study included all children who were consecutively born at 22 to 26 gestational weeks in Sweden from April 1, 2004, through March 31, 2007. At 6.5 years, 441 preterm children were evaluated alongside 371 controls. A total of 275 preterm children (62.4%) and 359 term-born children (96.8%) did not have neurodevelopmental disabilities. Motor assessments were completed for 229 of 275 preterm children (83.3%) and 344 of 359 (95.8%) term-born children, who composed the final study sample.

MAIN OUTCOMES AND MEASURES

Developmental coordination disorder was defined as a score of the fifth percentile or lower on the Movement Assessment Battery for Children-Second Edition scale, using control group scores. Assessment tools included the Wechsler Intelligence Scale for Children-Fourth Edition, the Brown Attention-Deficit Disorder Scales, the Five to Fifteen questionnaire, and the Strengths and Difficulties questionnaire.

RESULTS

Of the 229 extremely preterm children and 344 term-born controls who underwent motor assessments, 115 (50.2%) and 194 (56.4%) were boys, respectively. Developmental coordination disorder was present in 85 of 229 (37.1%) preterm children and in 19 of 344 controls (5.5%) (adjusted odds ratio [OR], 7.92; 99% CI, 3.69-17.20). When preterm children with developmental coordination disorder were compared with term-born peers, the risk was increased for total behavioral problems, internalizing, externalizing, attentional problems, hyperactivity, perceptual problems, executive dysfunction, and poor social skills, with adjusted ORs varying from 2.66 (99% CI, 1.09-6.48) for time concepts to 9.06 (99% CI, 3.60-22.8) for attentional problems (all P < .01). When preterm children with and without developmental coordination disorder were compared, preterm children with developmental coordination disorder had more behavioral problems; the adjusted OR for total behavioral problems was 2.71 (99% CI, 1.15-6.37); for externalizing problems, 2.80 (99% CI, 1.10-7.12); for inattention, 3.38 (99% CI, 1.39-8.18); and for combined attention/hyperactivity problems, 3.68 (99% CI, 1.47-9.16) (all P < .01). Parents underestimated the children's motor problems and only a few of the children had received psychological care or physiotherapy.

CONCLUSIONS AND RELEVANCE

Children who were born extremely preterm faced a high risk for developmental coordination disorder with associated comorbidities. Our findings support the importance of a structured follow-up of motor function, behavior, and cognition.

Risk Factor Models for Neurodevelopmental Outcomes in Children Born Very Preterm or With Very Low Birth Weight: A Systematic Review of Methodology and Reporting

The prediction of long-term outcomes in surviving infants born very preterm (VPT) or with very low birth weight (VLBW) is necessary to guide clinical management, provide information to parents, and help target and evaluate interventions. There is a large body of literature describing risk factor models for neurodevelopmental outcomes in VPT/VLBW children, yet few, if any, have been developed for use in routine clinical practice or adopted for use in research studies or policy evaluation. We sought to systematically review the methods and reporting of studies that have developed a multivariable risk factor model for neurodevelopment in surviving VPT/VLBW children. We searched the MEDLINE, Embase, and PsycINFO databases from January 1, 1990, to June 1, 2014, and identified 78 studies reporting 222 risk factor models. Most studies presented risk factor analyses that were not intended to be used for prediction, confirming that there is a dearth of specifically designed prognostic modeling studies for long-term outcomes in surviving VPT/VLBW children. We highlight the strengths and weaknesses of the research methodology and reporting to date, and provide recommendations for the design and analysis of future studies seeking to analyze risk prediction or develop prognostic models for VPT/VLBW children.

The motor profile of preterm infants at 11 y of age

BACKGROUND

Preterm infants are at a higher risk for poor motor outcome than term infants. This study aimed to describe the long-term motor profile in very preterm born children.

METHODS

A total of 98 very preterm infants were included. Volumetric brain magnetic resonance imaging (MRI) was performed at term age, and the Movement Assessment Battery for Children-Second Edition (The Movement ABC-2) was employed at 11 y of age. The diagnosis of Developmental Coordination Disorder (DCD) was determined at 11 y of age according to the International Classification of Diseases.

RESULTS

Eighty-two of 98 (84%) very preterm infants had normal motor development at 11 y of age. In these children, the mean percentile for the total test score in the Movement ABC-2 examinations was 42 (SD 20). Eight (8%) children had DCD. The mean percentile in these children was 4 (SD 2). Eight (8%) children had CP. Their mean percentile was 6 (SD 14). Decreased volumes in all brain regions associated with lower Movement ABC-2 total scores.

CONCLUSION

The majority of the very preterm infants had normal motor development at 11 y of age. Volumetric brain MRI at term age provides a potential tool to identify risk groups for later neuromotor impairment.

Prognostic factors for cerebral palsy and motor impairment in children born very preterm or very low birthweight: a systematic review

AIM

There is a large literature reporting risk factor analyses for poor neurodevelopment in children born very preterm (VPT: ≤32wks) or very low birthweight (VLBW: ≤1250g), which to date has not been formally summarized. The aim of this paper was to identify prognostic factors for cerebral palsy (CP) and motor impairment in children born VPT/VLBW.

METHOD

A systematic review was conducted using Medline, Embase, and Pyscinfo databases to identify studies published between 1 January 1990 and 1 June 2014 reporting multivariable prediction models for poor neurodevelopment in VPT/VLBW children (registration number CRD42014006943). Twenty-eight studies for motor outcomes were identified.

RESULTS

There was strong evidence that intraventricular haemorrhage and periventricular leukomalacia, and some evidence that the use of postnatal steroids and non-use of antenatal steroids, were prognostic factors for CP. Male sex and gestational age were of limited use as prognostic factors for CP in cohorts restricted to ≤32 weeks gestation; however, in children older than 5 years with no major disability, there was evidence that male sex was a predictive factor for motor impairment.

INTERPRETATION

This review has identified factors which may be of prognostic value for CP and motor impairment in VPT/VLBW children and will help to form the basis of future prognostic research.

Childhood motor coordination and adult psychopathology in extremely low birth weight survivors

OBJECTIVE

To determine if childhood motor coordination is associated with lifetime major depressive disorder (MDD), current generalized anxiety disorder (GAD), and attention-deficit/hyperactivity disorder (ADHD) in adulthood, and to examine if extremely low birth weight (ELBW; <1000 g) status moderates the strength of these associations.

METHOD

Prospective study of a cohort of normal birth weight (NBW) controls and ELBW survivors. Participants completed the short form Bruininks-Oseretsky Test of Motor Proficiency (BOTMP-SF) at age 8. At age 29-36, participants completed the Mini International Neuropsychiatric Interview to diagnose the psychiatric disorders of interest.

RESULTS

Birth weight status significantly influenced the strength and direction of associations between childhood motor coordination and adult psychiatric outcomes such that the odds of MDD (Pinteraction=.02) and GAD (Pinteraction=.01) increased with worsening motor scores in NBW adults but not ELBW survivors. Stratified analyses indicated that in NBW adults, for each one-point decrease in BOTMP-SF score, the odds of lifetime MDD increased by 10% (OR=1.10, 95% CI: 1.01-1.20).

LIMITATIONS

Participant attrition reduced sample size and that may have limited our ability to detect statistically significant results for some of our analyses.

CONCLUSION

Poorer motor coordination in early life has a negative long-term impact on the development of MDD and GAD of individuals born at NBW. The long-term mental health risks of childhood motor coordination problems are significant and highlight the importance of recognizing motor deficits in all children, so that associated psychological difficulties can be identified and treated at an early age.

Birthweight, body composition, and motor performance in 7- to 10-year-old children

AIM

The aim of this study was to analyse the influence of birthweight on motor performance and body composition in children. Further, we investigated whether associations between birthweight and motor performance changed after adjustment for current height, body mass index (BMI), fat-free mass (FFM), and % body fat.

METHOD

A total of 483 children (251 males and 232 females) aged 7 to 10 years (mean 8.78, SD 1.0y) born in Vitória Santo Antão (northeast Brazil) were sampled. Motor performance was operationalized using different physical fitness components and gross motor coordination. Physical fitness was measured by handgrip strength, muscle endurance, explosive power, flexibility, agility, running speed, and maximal oxygen consumption (VO2max). Gross motor coordination was evaluated by means of the Körper Koordination Test für Kinder (KTK).

RESULTS

Positive correlations between birthweight and height, BMI, and FFM were found. Birthweight was positively correlated with handgrip strength and negatively correlated with 20-meter sprint time, even after controlling for age, height, BMI, FFM, and % body fat. Birthweight was negatively associated with relative VO2max (mL/kg/min); however, the association was no longer significant after inclusion of BMI or FFM in the model.

INTERPRETATION

Birthweight significantly predicted height, BMI, FFM, and performance in strength and velocity tests, but did not influence gross motor coordination.

Motor performance, postural stability and behaviour of non-disabled extremely preterm or extremely low birth weight children at four to five years of age

BACKGROUND

Extremely preterm or extremely low birth weight (ELBW) children who are non-disabled and otherwise healthy are at risk of neurodevelopmental impairments. Further understanding of these impairments is needed before commencement of formal education to optimise participation levels at a critical time point for these children.

AIMS

To explore motor co-ordination, postural stability, limb strength and behaviour of non-disabled four to five year old children with a history of extreme prematurity or ELBW.

STUDY DESIGN

Prospective-descriptive-cohort-study.

SUBJECTS

50 children born at less than 28 weeks gestation or who had a birth weight less than 1000g with minimal/mild motor impairments and no significant neurological/cognitive impairments.

OUTCOME MEASURES

Movement Assessment Battery for Children second-edition (MABC-2), single leg stance test (SLS), lateral reach test, standing long jump test and Child Behaviour Checklist for preschool children (CBCL).

RESULTS

The mean percentile rank of the extremely preterm or ELBW sample on MABC-2 was 31% (SD 23%). SLS right (mean ± SD; 4.6 ± 2.5s) and lateral reach to the right (10.0 ± 3.9 cm) were slightly stronger than SLS left (4.4 ± 3.3s) and lateral reach left (9.9 ± 3.5 cm). The average for standing long jump was 71.6 cm (SD 21.0 cm). All participants were classified as 'normal' on CBCL syndrome scale scores, internalizing and externalizing syndrome T scores and total problem T score.

CONCLUSIONS

This sample of non-disabled extremely preterm or ELBW children performed in the lower range of normal. These children continue to be at risk of impairments, therefore, ongoing monitoring and tailored intervention may optimise development.

Motor impairment in very preterm-born children: links with other developmental deficits at 5 years of age

AIM

To elucidate the relation between motor impairment and other developmental deficits in very preterm-born children without disabling cerebral palsy and term-born comparison children at 5 years of (corrected) age.

METHOD

In a prospective cohort study, 165 children (81 very preterm-born and 84 term-born)were assessed with the Movement Assessment Battery for Children - 2nd edition, Touwen’s neurological examination, the Wechsler Preschool and Primary Scale of Intelligence, processing speed and visuomotor coordination tasks of the Amsterdam Neuropsychological Tasks, and the Strengths and Difficulties Questionnaire.

RESULTS

Motor impairment (≤15th centile) occurred in 32% of the very preterm-born children compared with 11% of their term-born peers (p=0.001). Of the very preterm-born children with motor impairment, 58% had complex minor neurological dysfunctions, 54% had low IQ, 69% had slow processing speed, 58% had visuomotor coordination problems, and 27%, 50%,and 46% had conduct, emotional, and hyperactivity problems respectively. Neurological outcome (odds ratio [OR]=41.7, 95% confidence intervals [CI] 7.5–232.5) and Full-scale IQ(OR=7.3, 95% CI 1.9–27.3) were significantly and independently associated with motor impairment. Processing speed (OR=4.6, 95% CI 1.8–11.6) and attention (OR=3.2, 95% CI1.3–7.9) were additional variables associated with impaired manual dexterity. These four developmental deficits mediated the relation between preterm birth and motor impairment.

INTERPRETATION

Complex minor neurological dysfunctions, low IQ, slow processing speed,and hyperactivity/inattention should be taken into account when very preterm-born children are referred for motor impairment.

Comparing two motor assessment tools to evaluate neurobehavioral intervention effects in infants with very low birth weight at 1 year

BACKGROUND

Infants with very low birth weight (VLBW) are at increased risk for motor deficits, which may be reduced by early intervention programs. For detection of motor deficits and to monitor intervention, different assessment tools are available. It is important to choose tools that are sensitive to evaluate the efficacy of intervention on motor outcome.

OBJECTIVE

The purpose of this study was to compare the Alberta Infant Motor Scale (AIMS) and the Psychomotor Developmental Index (PDI) of the Bayley Scales of Infant Development-Dutch Second Edition (BSID-II-NL) in their ability to evaluate effects of an early intervention, provided by pediatric physical therapists, on motor development in infants with VLBW at 12 months corrected age (CA).

DESIGN

This was a secondary study in which data collected from a randomized controlled trial (RCT) were used.

METHODS

At 12 months CA, 116 of 176 infants with VLBW participating in an RCT on the effect of the Infant Behavioral Assessment and Intervention Program were assessed with both the AIMS and the PDI. Intervention effects on the AIMS and PDI were compared.

RESULTS

Corrected for baseline differences, significant intervention effects were found for AIMS and PDI scores. The highest effect size was for the AIMS subscale sit. A significant reduction of abnormal motor development in the intervention group was found only with the AIMS.

LIMITATIONS

No Dutch norms are available for the AIMS.

CONCLUSIONS

The responsiveness of the AIMS to detect intervention effects was better than that of the PDI. Therefore, caution is recommended in monitoring infants with VLBW only with the PDI, and the use of both the AIMS and the Bayley Scales of Infant Development is advised when evaluating intervention effects on motor development at 12 months CA.

Imitation of 'bye-bye' in very low-birthweight infants

BACKGROUND

The aim of this study was to clarify the development of imitation skills in very low-birthweight (VLBW) infants compared with full-term infants with regard to the onset of 'bye-bye'.

METHODS

A total of 597 full-term infants (age, 6-21 months) and 95 VLBW infants (corrected age, 6-21 months) participated in this study. The time at which the infants began to imitate bye-bye and how they moved their hands were investigated by direct observations of their behaviors.

RESULT

Some full-term infants began to imitate bye-bye at 9 months, and all full-term infants could imitate bye-bye by 16 months old. The imitation of bye-bye was delayed in VLBW infants, but all of them could imitate it at 17 months old. Bye-bye motions were divided into five types. The 'moving wrist up and down' motion was observed most frequently at the initial bye-bye in both groups, but it was more frequent in VLBW infants at the early stage. The motion types changed with age, with the 'palm facing others' motion observed exclusively at 16 months in full-term infants. All infants of both groups could imitate this type at 17 months old.

CONCLUSION

The development of the ability to imitate bye-bye was delayed in VLBW infants even after correction for gestational age. It was suspected that the fine motor development delay might contribute to the late appearance of bye-bye in VLBW infants. Further follow-up study is required to clarify the clinical significance.

Relations among upper-limb movement organization and cognitive function at school age in children born preterm

OBJECTIVE

To explore relations between aspects of upper-body spatiotemporal movement organization and intelligence in children born preterm at school age.

METHODS

Three-dimensional (3D) kinematic recordings of arm and head movements during a unimanual precision task were related to performance on the Wechsler Intelligence Scale for Children, 4th edition, in a sample of 32 children born preterm (gestational age, mean: 31.5 weeks [range: 22-35 weeks]; birth weight, mean: 1699 g [range: 404-2962 g]) at 6 years to 8 years with no diagnosed cognitive, sensory, or motor impairments compared with 40 age-matched control children born fullterm.

RESULTS

In the children born preterm, upper-limb movement duration and segmentation of movement trajectories were significantly associated with full-scale intelligence quotient independent of gestational age (GA) and sex. These effects pertained to the preferred side, characterized by more effective movement organization being linked with increased intelligence scores. The same relations were not seen in the controls. Within the children born preterm, a significant effect of GA was also found for some aspects of upper-limb movement organization. Full-scale intelligence quotient was within normal limits for both groups but significantly lower in the preterm (mean: 94.5 [range: 72-120]) compared with the fullterm (mean: 101.7 [range: 76-119]) born children.

CONCLUSIONS

The findings demonstrate that, independent of GA, the spatiotemporal organization of upper-limb movements is partly associated with cognitive performance in children born preterm.

Does the Bayley-III Motor Scale at 2 years predict motor outcome at 4 years in very preterm children?

AIM

To assess the predictive validity of the Bayley Scales of Infant and Toddler Development - Third Edition (Bayley-III) for later motor outcome.

METHOD

Ninety-six infants (49 males, 47 females) born at less than 30 weeks' gestation admitted to two tertiary hospitals in Melbourne, Australia, were assessed with the Bayley-III Motor Scale at 2 years' corrected age and were classified as suspect or definite motor impairment if they scored less than -1 or -2 standard deviations respectively, relative to the test mean. At 4 years' corrected age, children completed Movement Assessment Battery for Children - Second Edition (MABC-2); for the total motor score, cut-offs of not more than the 15th were used to classify motor development and cut-offs of not more than the 15th centile were classified as having a significant movement difficulty.

RESULTS

Of the 96 children assessed at both ages, at 2 years 9% had suspect and 4% had definite motor impairment; however, by 4 years, rates had increased to 22% and 19% respectively. The specificity of the Bayley-III for motor impairments for later motor outcome was excellent (ranging from 94 to 100% for cerebral palsy [CP] and 97 to 100% for motor impairment), although the sensitivity was low (ranging from 67 to 83% for CP and 18 to 37% for motor impairment); many children with later impairment were not identified by the Bayley-III.

INTERPRETATION

The Bayley-III Motor Scale at 2 years underestimates later rates of motor impairment, particularly in the absence of CP at 4 years on the MABC-2 total motor score in children born at less than 30 weeks' gestational age.

Cognitive outcomes for extremely preterm/extremely low birth weight children in kindergarten

Our objectives were to examine cognitive outcomes for extremely preterm/extremely low birth weight (EPT/ELBW, gestational age <28 weeks and/or birth weight <1000 g) children in kindergarten and the associations of these outcomes with neonatal factors, early childhood neurodevelopmental impairment, and socioeconomic status (SES). The sample comprised a hospital-based 2001-2003 birth cohort of 148 EPT/ELBW children (mean birth weight 818 g; mean gestational age 26 weeks) and a comparison group of 111 term-born normal birth weight (NBW) classmate controls. Controlling for background factors, the EPT/ELBW group had pervasive deficits relative to the NBW group on a comprehensive test battery, with rates of cognitive deficits that were 3 to 6 times higher in the EPT/ELBW group. Deficits on a measure of response inhibition were found in 48% versus 10%, odds ratio (95% confidence interval) = 7.32 (3.32, 16.16), p < .001. Deficits on measures of executive function and motor and perceptual-motor abilities were found even when controlling for acquired verbal knowledge. Neonatal risk factors, early neurodevelopmental impairment, and lower SES were associated with higher rates of deficits within the EPT/ELBW group. The findings document both global and selective cognitive deficits in EPT/ELBW children at school entry and justify efforts at early identification and intervention.

The changing yardstick in measurement of cognitive abilities in infancy

There are concerns regarding accurate measurement of cognitive function in infants, particularly those at biologic risk. Herein we discuss these issues and make recommendations. Concerns include: 1) secular changes in test norms, referred to as the Flynn effect; 2) changes in the content of revised test versions; 3) recent findings of higher mean scores in newer test versions when compared to previous scores; and 4) correction for prematurity. Caution is necessary when comparing the same test scores over extended periods of time, and using different versions of the same test when mean scores of the tests vary or evaluate different areas of functioning. Ideal solutions are not readily apparent and thus we provide several suggestions: control groups are essential for longitudinal studies; clinicians should not rely totally on cognitive scores; and further investigation of the Flynn effect in different subgroups of children at different ages is necessary.