Comparison of chronological and corrected ages in the gross motor assessment of low-risk preterm infants during the first year of life

Effects of Correcting for Prematurity on Executive Function Scores of Children Born Very Preterm at School Age

OBJECTIVE

To investigate whether correction for prematurity affects executive function scores in school-aged children born very preterm.

STUDY DESIGN

Executive functions were assessed with standardized neuropsychological tests in 142 children born very preterm (born at ≤32 weeks of gestational age or with a birth weight of ≤1500 g) and 391 control children, aged 7-13 years. Four-month age bands were established from the data of control children. Differences between uncorrected and corrected scores were compared against zero difference and between very preterm children born before and after 28 weeks of gestation. Regression models were used to compare the uncorrected and corrected scores of children born very preterm with control children.

RESULTS

For all executive functions, significant, larger-than-zero differences between uncorrected and corrected scores were apparent in children born very preterm. Mean differences ranged from 0.04 to 0.18 SDs. Weak evidence was found that the effect of age correction is more pronounced in very preterm children born before 28 weeks of gestation than in those born after 28 weeks. Differences in executive function scores between children born very preterm and control children were attenuated if scores were corrected for prematurity.

CONCLUSIONS

Test scores based on corrected rather than uncorrected age may more accurately determine the developmental stage of very preterm children's executive functions at school age. Potential consequences for clinical and research practice need to be discussed in the future.

Consequences of using chronological age versus corrected age when testing cognitive and motor development in infancy and intelligence quotient at school age for children born preterm

BACKGROUND

Children born preterm (<37 weeks' gestation) have an increased risk of poor neurodevelopment, including lower intelligence quotient (IQ) scores compared with their term-born counterparts.

OBJECTIVE

To explore the differences in psychometric scores for cognition and motor skills when they are age-standardized according to chronological age instead of corrected age for children born preterm.

METHODS

We assessed = 554 children born <33 weeks' gestation with the Bayley Scales of Infant Development, 2nd edition (mental and motor scores) at 18 months and the Weschler Abbreviated Scale of Intelligence (IQ score) at seven years of age. Scores were standardized according to chronological age and corrected age and differences between mean chronological and corrected scores were compared, along with the proportion of children whose scores could be classified as impaired.

RESULTS

When scores were standardized according to chronological age instead of corrected age there was a large significant difference of 17.3 points on the mental scale (79.5 vs. 96.8, respectively) and 11.8 points on the motor scale (84.8 vs. 96.6, respectively) at 18 months. By seven years, the difference in IQ scores remained, although of a smaller magnitude at 1.9 points between mean chronological and corrected age scoring (97.2 vs. 99.1, respectively).

CONCLUSION

Consistent with previous literature, outcome assessments for preterm infants consistently differed according to use of chronological or corrected age to standardized scores. Cognitive scores were impacted more severely than motor scores, and differences were more substantial in early childhood than later in childhood. For clinical purposes, correction for preterm birth is only likely to have an impact during early childhood, however assessments for research purposes should continue to correct into childhood to account for the persistent bias due to preterm birth.

Is It Correct to Correct for Prematurity? Theoretic Analysis of the Bayley-4 Normative Data

OBJECTIVE

To determine whether correction for prematurity is appropriate for cognitive, language, and motor function at varying degrees of prematurity and at different baseline functional levels.

METHODS

The newly published Bayley-4 normative data on 1700 normal children were used. Raw scores for baseline levels of function (-2 SD, -1 SD, and M) were identified at 6, 12, 24, and 36 months for receptive communication, expressive communication, fine motor, and gross motor scaled scores and cognitive, language, and motor composite scores. Differences between the baseline and uncorrected scores at 4, 3, 2, and 1 months of prematurity were evaluated at each age.

RESULTS

Using a cutoff of 3 points (1/5 SD), correction is needed for cognitive composite scores at all gestational ages for the first 2 years and in those born 4 months premature at 3 years of age; language and motor composite scores should be corrected to 3 years at all degrees of prematurity.

CONCLUSION

Not correcting for prematurity in cognitive, language, and motor function at 3 years and younger places preterm infants at a distinct disadvantage when compared to peers with few exceptions, suggesting that such correction should be routine.

Motor trajectories of preterm and full-term infants in the first year of life

BACKGROUND

Motor development occurs throughout periods of motor skill acquisition, adjustment and variability. The objectives of this study were to analyze and compare biological and health characteristics and motor skill acquisition trajectories in preterm and full-term infants during the first year of life.

METHODS

Two thousand, five hundred and seventy-nine infants (1,361 preterm) from 22 states were assessed using the Alberta Infant Motor Scale. Multivariate General Linear Model, t-tests, ANOVA, and Tukey tests were used.

RESULTS

An age × group significant interaction was found for motor scores. On follow-up tests full-term infants had higher scores in prone, supine, sitting and standing postures that require trunk control from 9 to 10 months of age; although this advantage was observed for sitting from the second month of life.

CONCLUSION

During the first trimester of life, preterm infants have higher scores in the supine and standing postures. Regarding motor trajectories, from newborn to 12 months, the period of higher motor acquisition was similar between full-term and preterm infants for prone (3-10 months), supine (1-6 months), and standing (6-12 months). For the sitting posture, however, full-term infants had a period of intensive motor learning of acquisition from the first to 7 months of life, whereas for preterm infants a shorter period was observed (3-7 months).

CONCLUSION

Although the periods of higher motor acquisition were similar, full-term infants had higher scores in more control-demanding postures. Intervention for preterm infants needs to extend beyond the first months of life, and include guidance to parents to promote motor development strategies to achieve control in the higher postures.

Developmental assessment of preterm infants: Chronological or corrected age?

The aim of this study is to examine the effect of age correction on the developmental assessment scores of preterm infants, using for the first time, the Mullen scales of early learning (MSEL) test. Participants included 110 preterm infants (born at a gestational age of ≤ 34 weeks) at ages 1, 4, 8, 12, 18, 24 and 36 months. The corrected age-based MSEL composite score and each of the five MSEL scale scores were significantly higher than chronological age-based scores at all ages. These corrected scores were significantly higher than the chronological scores regardless of gestational age whether weight was, or adequate or small for gestational age. Larger differences between corrected and chronological age-based scores significantly correlated with earlier gestational age and with lower birth weight between 1 and 24 months but not at 36 months. Using chronological age-based scores yielded significantly more infants identified with developmental delays than using corrected age-based scores. The findings indicate that clinicians and researchers, as well as family members, should be aware of and acknowledge the distinction between corrected and chronological ages when evaluating preterm infants in research and clinical practices.

Age correction in cognitive, linguistic, and motor domains for infants born preterm: an analysis of the Bayley Scales of Infant and Toddler Development, Third Edition developmental patterns

AIM

To verify whether it is appropriate to use age correction for infants born preterm in all the developmental domains (cognitive, linguistic, and motor) considered by the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III).

METHOD

Seventy-three infants born preterm (26-35wks) without major neurological sequelae and 67 infants born at term were assessed at 12 months (corrected age for infants born preterm). The performance of the infants born preterm was assessed with two different evaluations: scores based on uncorrected age and scores based on corrected age.

RESULTS

The developmental trends of infants born at term and infants born preterm differ across domains. Statistical analysis shows that age correction produces an overrated estimate of motor performance (12.5 points [95% confidence interval 9.05-16.01]) but not of cognitive performance.

INTERPRETATION

Given the broad use of the Bayley-III by psychologists and paediatricians, these results are important in the early diagnosis of developmental difficulties for children born preterm. Correction for gestational age should be applied for the cognitive domain only; whereas for the motor domain, chronological age should be used. No clear data emerged for language.

WHAT THIS PAPER ADDS

Age correction with Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) for infants born preterm should be applied differently in cognitive, language, and motor domains. Using corrected age with Bayley-III, the motor skills are overrated. Correction for preterm births adequately measures cognitive skills. No clear indication emerged about language skills.

Motor development of preterm infants assessed by the Alberta Infant Motor Scale: systematic review article

OBJECTIVE

Premature newborns are considered at risk for motor development deficits, leading to the need for monitoring in early life. The aim of this study was to systematically review the literature about gross motor development of preterm infants, assessed by the Alberta Infant Motor Scale (AIMS) to identify the main outcomes in development.

DATA SOURCE

Systematic review of studies published from 2006 to 2015, indexed in Pubmed, Scielo, Lilacs, and Medline databases in English and Portuguese. The search strategy included the keywords: Alberta Infant Motor Scale, prematurity, preterm, motor development, postural control, and follow-up.

DATA SUMMARY

A total of 101 articles were identified and 23 were selected, according to the inclusion criteria. The ages of the children assessed in the studies varied, including the first 6 months up to 15 or 18 months of corrected age. The percentage variation in motor delay was identified in the motor outcome descriptions of ten studies, ranging from 4% to 53%, depending on the age when the infant was assessed. The studies show significant differences in the motor development of preterm and full-term infants, with a description of lower gross scores in the AIMS results of preterm infants.

CONCLUSIONS

It is essential that the follow-up services of at-risk infants have assessment strategies and monitoring of gross motor development of preterm infants; AIMS is an assessment tool indicated to identify atypical motor development in this population.

Functional development of preterm infants: an integrative literature review

Abstract Introduction: Prematurity is a public health problem. Despite many studies that aim to characterize the effects of premature birth on the various dimensions of child development, there is still little systematic evidence on the functional dimension. Objective: To characterize the functional development of preterm infants in early infancy. Methods: Searches were conducted in PubMed, Science Direct, Scopus, Cochrane, Joana Briggs Institute, Embase, Lilacs and SciELO databases, with the following key words in English and Portuguese and their combinations: preterm, functional performance, functional outcomes, functional limitations, functional skills, activities of daily living and disability. Inclusion criteria were articles published in the last seven years on the investigated subject. Results: The five articles in the sample were organized, analyzed and categorized, reaching up to three empirical categories of analysis: Functional Performance of Preterm, Cumulative Effects on Functional Development, and Environmental Context and Attitudes of Care. Conclusion: It was concluded that before age 6, children born premature have developmental delays in functional areas of self-care, mobility and social function. Their functional development suffers cumulative effects of various different factors and may be related to care practices and context.

Effect of maturation on suprasegmental speech processing in full- and preterm infants: a mismatch negativity study

Infants born prematurely are at higher risk for later linguistic deficits present in delayed or atypical processing of phonetic and prosodic information. In order to be able to specify the nature of this atypical development, it is important to investigate the role of early experience in language perception. According to the concept of Gonzalez-Gomez and Nazzi (2012) there is a special intrauterine sensitivity to the prosodic features of languages that should have a special role in language acquisition. Therefore, we may also assume that pre- and full-term infants having months difference in intrauterine experience show different maturation patterns of processing prosodic and phonetic information present at word level. The aim of our study was to investigate the effect of these differences on word stress pattern vs. phoneme information processing. Two age groups of infants (6 and 10 month-olds) were included in our study. 21 of 46 of the total of infants investigated were prematurely born with low birth weight. We used the mismatch negativity (MMN) event related brain potential (ERP) component, a widely used electrophysiological correlate of acoustic change detection, for testing the assumed developmental changes of phoneme and word stress discrimination. In a passive oddball paradigm we used a word as standard, a pseudo-word as phoneme deviant, and an illegally uttered word as stress deviant. Our results showed no differences in MMN responses in the phoneme deviant condition between the groups, meaning a relatively intact maturation of phoneme processing of preterm infants as compared to their contemporaries. However, the mismatch responses measured in the stress condition revealed significant between-group differences. These results strengthen the view that the total length of intrauterine experience influences the time of emergence of prosodic processing.

Assessing gross motor development of Brazilian infants

PURPOSE

To determine whether the Alberta Infant Motor Scale (AIMS) requires reference values specific for Brazilian infants.

METHODS

A total of 660 (330 girls) healthy full-term infants from Belo Horizonte were assessed using the AIMS. Scores and percentile curves were compared with the Canadian reference values.

RESULTS AND DISCUSSION

Differences were found in the 5th percentile (9-<10 and 10-<11 months) and the 10th percentile (4-<5, 9-<10, and 10-<11 months) curves. No significant differences were found between sexes on the basis of the economic classification or the criteria of the Human Development Index.

CONCLUSION

Primarily because of the corrections made to the 5th and 10th percentile curves, we recommend the use of the Brazilian infant data curves reported here for further studies conducted in Brazil. Because the Human Development Index of Belo Horizonte is similar to that for Brazil as a whole, the results of this study should be relevant for clinicians throughout Brazil.

Provider use of corrected age during health supervision visits for premature infants

INTRODUCTION

Correcting age for prematurity is recommended by the American Academy of Pediatrics and the Centers for Disease Control and Prevention. The use of chronological age instead of corrected age for infants born prematurely may result in incorrect interpretations regarding the adequacy of a child's growth or developmental progress and has the potential to negatively affect care. This study examined the frequency and impact of the use of corrected age by primary care providers.

METHOD

A retrospective cross-sectional electronic health record review was performed for all infants < 32 weeks' gestation who were seen for a health supervision visit in a 31-site pediatric network during a 1-year period. Primary care providers used an electronic health record that defaulted to chronological age information.

RESULTS

Primary care providers used corrected age for developmental surveillance for 24% of visits, they used chronological age for 71% of visits, and the age used was unclear in 5% of visits. The lower a child's gestational age and the more that chronological age was used, the more concerns were identified by primary care providers. Dietary changes that included the introduction of solid foods, the start of fluoride, and the introduction of milk typically were recommended on the basis of chronological age.

DISCUSSION

Primary care providers used chronological age more than corrected age, which influenced assessment and recommendations for care. This study illustrates the impact of not using corrected age, the importance of ensuring that care aligns with guidelines, and the possible influence of the design of the electronic health record on patient care. Because families of premature infants rely on primary care providers to accurately identify sequelae associated with prematurity, and to provide reassurance when it is warranted, these findings have implications for all health care providers who treat premature infants.

Differences in walking attainment ages between low-risk preterm and healthy full-term infants

OBJECTIVE: To compare gross motor development of preterm infants (PT) without cerebral palsy with healthy full-term (FT) infants, according to Alberta Infant Motor Scale (AIMS); to compare the age of walking between PT and FT; and whether the age of walking in PT is affected by neonatal variables. METHODS: Prospective study compared monthly 101 PT and 52 FT, from the first visit, until all AIMS items had been observed. Results: Mean scores were similarity in their progression, except from the eighth to tenth months. FT infants were faster in walking attainment than PT. Birth weight and length and duration of neonatal nursery stay were related to walking delay. CONCLUSION: Gross motor development between PT and FT were similar, except from the eighth to tenth months of age. PT walked later than FT infants and predictive variables were birth weight and length, and duration of neonatal intensive unit stay.

Psychomotor development of preterm infants aged 6 to 12 months

CONTEXT AND OBJECTIVE

The immaturity of preterm infants' organ systems may lead to difficulties in adapting to different environmental stimuli. The aim was to compare the psychomotor development of preterm infants (with corrected age) and term infants aged 6 to 12 months and to investigate associated factors.

DESIGN AND SETTING

Cross-sectional analytical study conducted at Hospital das Clínicas, Universidade Federal de Pernambuco.

METHODS

The sample consisted of 135 infants (45 preterm and 90 full-term) aged 6 to 12 months. Neuropsychomotor development was assessed using the Bayley III cognitive, language and motor subscales. Biological, socioeconomic and demographic data were gathered from medical records and through interviews with mothers.

RESULTS

The mean cognitive, language and motor indices were within the range of normality for the sample as a whole. No significant difference in the development of infants born preterm and full-term was observed, except for expressive communication, in which preterm infants presented a lower index. Motor development was influenced by biological factors, and the poorest performances were observed in male infants; birth weight birth weight < 1500 g; Apgar score at five minutes < 7; weight-, length- and head circumference-for-age < -1 Z-score; and exclusively breastfeeding for < two months.

CONCLUSIONS

Prematurity did not influence the psychomotor development of infants in this study population. Motor development was the most affected domain in the sample as a whole, especially due to biological factors. Investigations on child neuropsychomotor development should try to identify many determinant factors because of its multifactorial nature.

Motor development curve from 0 to 12 months in infants born preterm

AIM

To trace a reference curve for motor development from birth up to 12 months of corrected chronological age in infants born preterm and low birth weight.

METHODS

This is a cross-sectional study with a sample of 308 preterm infants (53% boys) weighing < 2500 g at birth. The Alberta Infant Motor Scale (AIMS) was used for motor development assessment.

RESULTS

Comparing the motor performance of preterm infants with infants from a standardized sample on the AIMS, it was found that, except for the age group of the newborn, preterm infants showed lower motor development scores in comparison with the AIMS normative sample in all age groups between 1 and 12 months. The curve of motor development showed a continuous increase in the number of motor skills of preterm infants during their first 12 months of age. However, the average of motor acquisitions of preterm infants showed a nonlinear pattern with a standard indicator of stabilization between 8 and 10 months of age.

CONCLUSION

Preterm infants, 1-12 months of age, showed motor development AIMS scores lower than the standards established in the normative sample. The findings may contribute as norm-reference for assessing the motor development of preterm infants in follow-up programmes in developing countries.

Motor Development of Premature Infants Born between 32 and 34 Weeks

Little is known about motor development in late preterm born infants. Our objective was to determine long-term outcome of motor skills of infants born between 32 and 34 weeks. All infants were assessed at corrected ages of 3 and 9 months, using the Alberta Infant Motor Scale. At corrected ages of 4 years, the Movement Assessment Battery for Children was done. Seventy infants were seen at 4 years of age (median of 3 assessments per infant). Abnormal assessment at 3 or 9 months of age resulted in normal outcome in almost 80% at 4 years. On the other hand, a normal outcome in the first year of life resulted in an abnormal outcome at 4 years in 10% of the infants. Our results suggest that long-term followup of these late preterm born infants is necessary, as the assessments in the first year do not predict the long-term outcome.

Concurrent validity of the parent-completed Ages and Stages Questionnaires, 2nd Ed. with the Bayley Scales of Infant Development II in a low-risk sample

Abstract Background This study assessed the concurrent validity of the Ages and Stages Questionnaire (ASQ) compared with Bayley Scales of Infant Development II (BSID II) amongst children aged 24 months. Methods Data were collected from 53 infants and mothers who participated in the New York State Angler Cohort Child Development Study. Parents completed the 24-month ASQ to assess communication, personal-social, problem-solving ability, and fine and gross motor control. The BSID II was administered by a clinical psychologist at the 24-month home visit for cognitive and psychomotor assessment. The ASQ was scored using age-specific norms of <2 SDs below any domain mean to define failure. A BSID II score of <85 indicated mild or severe delay, while a score of <70 suggested a severe delay. Results Scores on the ASQ communication and personal-social domains were moderately correlated with the BSID II Mental Scale (R= 0.52, P < 0.001; R= 0.45, P < 0.01) and ASQ gross motor with the BSID II Motor Scale (R= 0.46, P < 0.01), whereas ASQ problem-solving and fine motor domains were not significantly correlated with BSID II scores. The ASQ had a sensitivity of 100% and specificity of 87% at 24 months (n= 40) for severely delayed status. Conclusions Results suggest the ASQs provide a simple, valid, and cost-effective method for clinicians and field-based researchers to reduce the number of standardized assessments required to identify developmentally delayed infants at age 24 months. Future studies should further assess the validity of the ASQs in larger, more diverse populations of infants.

Caracterização dos fatores ambientais e o controle cervical de lactentes nascidos pré-termo

OBJETIVO: Caracterizar os fatores ambientais e a aquisição do controle cervical dos lactentes nascidos pré-termo, de recém-nascido aos 4 meses de idade corrigida, nas posturas prona e sentada. METODOLOGIA: Participaram do estudo 18 lactentes, sendo 9 pré-termo (33 semanas ± 2 semanas) e 9 a termo (39 semanas ± 1 semana). Foi aplicado o Test of Infant Motor Performance (TIMP), para avaliar o controle cervical dos lactentes, e um questionário para as mães, mês a mês. RESULTADOS: Não houve diferença significativa no desenvolvimento do controle cervical entre os grupos no decorrer dos meses, mas os lactentes nascidos a termo apresentaram escore superior ao pré-termo nos itens 32, 35 e 36 da escala TIMP na idade de recém-nascido. CONCLUSÃO: Sugere-se que a diferença de escore na idade de RN entre os grupos pode estar relacionada tanto com as alterações orgânicas que os lactentes pré-termo apresentam quanto aos fatores ambientais.

Avaliação longitudinal do desenvolvimento motor e da habilidade de sentar em crianças nascidas prematuras

Os bebês prematuros apresentam maior risco para atrasos na aquisição das habilidades neuromotoras. O objetivo do estudo foi detectar atrasos no desenvolvimento motor de crianças prematuras com baixo peso, analisar a evolução da habilidade do sentar e verificar a associação entre essa habilidade com outras aquisições motoras até os 8 meses de idade corrigida (IC). Foram avaliadas 10 crianças nascidas pré-termo, de ambos os sexos, dos 4 aos 8 meses de IC, pela escala motora infantil de Alberta AIMS (Alberta Infant Motor Scale). Cada criança foi avaliada três vezes, aos 4 para 5 meses, 5 para 6 meses, e 7 para 8 meses; os escores foram comparados para verificar alterações ao longo do tempo e identificação de possíveis atrasos no desenvolvimento motor. Os resultados mostram que, aos 7 para 8 meses, 30% das crianças apresentaram desenvolvimento motor atrasado e foram encaminhadas para tratamento fisioterapêutico. A habilidade de sentar foi melhorando progressiva e significativamente com a idade, tendo se mostrado fortemente correlacionada com outras posturas do desenvolvimento motor e com o escore total na AIMS.

An evidentiary review regarding the use of chronological and adjusted age in the assessment of preterm infants

PURPOSE

The evidence supporting the recommendation to use age adjustment when assessing the growth, motor, and global development of premature infants was explored. Following a comprehensive literature search, 16 articles that compared the use of adjusted and chronological age were reviewed.

CONCLUSIONS

The use of full age adjustment based on the degree of prematurity was supported for the assessment of premature infants for a minimum of 12 months adjusted age.

PRACTICE IMPLICATIONS

The use of adjusted age enhances the ability to accurately recognize genuine delays as opposed to perceived delays related to a child's gestational age at birth.

Predictive factors for neuromotor abnormalities at the corrected age of 12 months in very low birth weight premature infants

BACKGROUND: The increase in survival of premature newborns has sparked growing interest in the prediction of their long-term neurodevelopment. OBJECTIVE: To estimate the incidence of neuromotor abnormalities at the corrected age of 12 months and to identify the predictive factors associated with altered neuromotor development in very low birth weight premature infants. METHOD: Cohort study. The sample included 100 premature infants. The outcome was neuromotor development at 12 months classified by Bayley Scale (PDI) and neurological assessment (tonus, reflexes, posture). A multivariate logistic regression model was constructed. Neonatal variables and neuromotor abnormalities up to 6 months of corrected age were selected by bivariate analysis. RESULTS: Mean birth weight was 1126g (SD: 240). Abnormal neuromotor development was presented in 60 children at 12 months corrected age. CONCLUSION: According to the model, patients with a diagnosis including bronchopulmonary dysplasia, hypertonia of lower extremities, truncal hypotonia showed a 94.0% probability of neuromotor involvement at 12 months.