Associations between gestational age and childhood sleep: a national retrospective cohort study.

BACKGROUND: Both sleep quality and quantity are essential for normal brain development throughout childhood; however, the association between preterm birth and sleep problems in preschoolers is not yet clear, and the effects of gestational age across the full range from preterm to post-term have not been examined. Our study investigated the sleep outcomes of children born at very-preterm (<31 weeks), moderate-preterm (32-33 weeks), late-preterm (34-36 weeks), early-term (37-38 weeks), full-term (39-40 weeks), late-term (41 weeks) and post-term (>41 weeks). METHODS: A national retrospective cohort study was conducted with 114,311 children aged 3-5 years old in China. Children's daily sleep hours and pediatric sleep disorders defined by the Children's Sleep Habits Questionnaire (CSHQ) were reported by parents. Linear regressions and logistic regression models were applied to examine gestational age at birth with the sleep outcomes of children. RESULTS: Compared with full-term children, a significantly higher CSHQ score, and hence worse sleep, was observed in very-preterm (ß = 1.827), moderate-preterm (ß = 1.409), late-preterm (ß = 0.832), early-term (ß = 0.233) and post-term (ß = 0.831) children, all p<0.001. The association of pediatric sleep disorder (i.e. CSHQ scores>41) was also seen in very-preterm (adjusted odds ratio [AOR] = 1.287 95% confidence interval [CI] (1.157, 1.433)), moderate-preterm (AOR = 1.249 95% CI (1.110, 1.405)), late-preterm (AOR = 1.111 95% CI (1.052, 1.174)) and post-term (AOR = 1.139 95% CI (1.061, 1.222)), all p<0.001. Shorter sleep duration was also found in very-preterm (ß = -0.303), moderate-preterm (ß = -0.282), late-preterm (ß = -0.201), early-term (ß = -0.068) and post-term (ß = -0.110) compared with full-term children, all p<0.01. Preterm and post-term-born children had different sleep profiles as suggested by subscales of the CSHQ. CONCLUSIONS: Every degree of premature, early-term and post-term birth, compared to full-term, has an association with sleep disorders and shortened daily sleep duration. Preterm, early-term, and post-term should therefore all be monitored with an increased threat of sleep disorder that requires long-term monitoring for adverse sleep outcomes in preschoolers.

Lifestage differences in young UK women's reasons for research participation.

Lifecourse epidemiology suggests that preconception is a valuable opportunity for health promotion with young women. Yet young women are less likely than older women to be research participants, limiting evidence about their needs and risks. Marketing data indicate that young adults are not engaged with one advertising strategy because they transition through three life stages: (i) limited independence and focus on own interests, (ii) increased independence and time with peers and (iii) establishing a home and family. The aim of this study was to explore whether these marketing lifestage categories could inform the tailoring of strategies to recruit young women. Three focus groups per lifestage category were conducted (49 women aged 16-34 years). Lifestage category (i) was represented by further education students, category (ii) by women in workplaces and (iii) by mothers. Questions explored participants' lifestyles, identity, reasons for participation in the current study and beliefs about researchers. Three major themes were identified through framework analysis: profiling how young women spend their time; facilitators of participating in research and barriers to participating. Students and women in work valued monetary remuneration whereas mothers preferred social opportunities. Participants' perceived identity influenced whether they felt useful to research. All groups expressed anxiety about participation. Altruism was limited to helping people known to participants. Therefore, the marketing categories did not map exactly to differences in young women's motivations to participate but have highlighted how one recruitment strategy may not engage all. Mass media communication could, instead, increase familiarity and reduce anxiety about participation.

International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder.

AIM: These international clinical practice recommendations (CPR) for developmental coordination disorder (DCD), initiated by the European Academy of Childhood Disability (EACD), aim to address key questions on the definition, diagnosis, assessment, intervention, and psychosocial aspects of DCD relevant for clinical practice. METHOD: Key questions in five areas were considered through literature reviews and formal expert consensus. For recommendations based on evidence, literature searches on 'mechanisms', 'assessment', and 'intervention' were updated since the last recommendations in 2012. New searches were conducted for 'psychosocial issues' and 'adolescents/adults'. Evidence was rated according to the Oxford Centre for Evidence-Based Medicine (level of evidence [LOE] 1-4) and transferred into recommendations. For recommendations based on formal consensus, two meetings of an international, multidisciplinary expert panel were conducted with a further five Delphi rounds to develop good clinical practice (GCP) recommendations. RESULTS: Thirty-five recommendations were made. Eight were based on the evidence from literature reviews (three on 'assessment', five on 'intervention'). Twenty-two were updated from the 2012 recommendations. New recommendations relate to diagnosis and assessment (two GCPs) and psychosocial issues (three GCPs). Additionally, one new recommendation (LOE) reflects active video games as adjuncts to more traditional activity-oriented and participation-oriented interventions, and two new recommendations (one GCP, one LOE) were made for adolescents and adults with DCD. INTERPRETATION: The CPR-DCD is a comprehensive overview of DCD and current understanding based on research evidence and expert consensus. It reflects the state of the art for clinicians and scientists of varied disciplines. The international CPR-DCD may serve as a basis for national guidelines. WHAT THIS PAPER ADDS: Updated international clinical practice guidelines on developmental coordination disorder (DCD). Refined and extended recommendations on clinical assessment and intervention for DCD. A critical synopsis of current research on mechanisms of DCD. A critical synopsis of psychosocial issues in DCD, with implications for clinical practice. The first international recommendations to consider adolescents and adults with DCD.

Research recruitment: A marketing framework to improve sample representativeness in health research.

AIMS: This discussion paper proposes a five-part theoretical framework to inform recruitment strategies. The framework is based on a marketing model of consumer decision-making. BACKGROUND: Respondents in surveys are typically healthier than non-respondents, which has an impact on the availability of information about those most in need. Previous research has identified response patterns, provided theories about why people participate in research and evaluated different recruitment strategies. Social marketing has been applied successfully to recruitment and promotes focus on the needs of the participant, but little attention has been paid to the periods before and after participant-researcher contact (during advertising and following completion of studies). We propose a new model which conceptualises participation as a decision involving motivation, perception of information, attitude formation, integration of intention and action and finally evaluation and sharing of experience. DESIGN: Discussion paper. DATA SOURCES: This discussion paper presents a critical review. No literature was excluded on date and the included citations span the years 1981-2017. IMPLICATIONS FOR NURSING: The proposed framework suggests that researchers could engage a broader demographic if they shape research design and advertising to perform functions that participants are seeking to achieve. The framework provides a novel and useful conceptualisation of recruitment which could help to inform public engagement in research design, researcher training and research policy. CONCLUSION: This framework challenges researchers to investigate the goals of the potential participants when designing a study's advertising and procedures.

Patterns of response by sociodemographic characteristics and recruitment methods for women in UK population surveys and cohort studies.

Women are an important public health focus, because they are more likely to experience some social determinants of disease, and they influence family health. Little research has explored the sociodemographic representativeness of women in research studies. We examined the representativeness of female respondents across four sociodemographic factors in UK population surveys and cohort studies. Six UK population-based health surveys (from 2009-2013) and eight Medical Research Council cohort studies (from 1991 to 2014) were included. Percentages of women respondents by age, income/occupation, education status, and ethnicity were compared against contemporary population estimates. Women aged <35 years were under-represented. The oldest women were under-represented in four of nine studies. Within income/occupation, at the highest deprivation level, the range was 4 percent under-representation to 43 percent over-representation; at the lowest level, it was 6 percent under-representation to 21 percent over representation. Of nine studies reporting educational level, four under-represented women without school qualifications, and three under-represented women with degrees. One of five studies over-represented non-white groups and under-represented white women (by 9 percent). Response patterns varied by topic and recruitment and data collection methods. Future research should focus upon the methods used to identify, reach, and engage women to improve representativeness in studies addressing health behaviors.

Understanding handwriting difficulties: A comparison of children with and without motor impairment.

The nature of handwriting difficulties have been explored in children with specific developmental disorders. The aim of this study was to investigate the nature of handwriting difficulties in children with dysgraphia, a less studied group who have significant handwriting difficulties in the absence of motor control or cognitive difficulties. The performance of a dysgraphia group aged 8-14 years was compared to a group with Developmental Coordination Disorder and to typically developing (TD) controls. Participants completed two handwriting tasks on a digitizing writing tablet. The amount and accuracy of the handwriting product was measured, plus various temporal and spatial features of the writing process. There were no significant differences in performance between the two groups with handwriting difficulties but both performed more poorly than the TD group. Individual differences in the type and severity of handwriting impairments suggest the need for a range of classroom assessments to tailor intervention appropriately.

Navigating through apertures: perceptual judgements and actions of children with Developmental Coordination Disorder.

Passing through a narrow gap/aperture involves a perceptual judgement regarding the size of the gap and an action to pass through. Children with DCD are known to have difficulties with perceptual judgements in near space but whether this extends to far space is unknown. Furthermore, in a recent study it was found that adults with DCD do not scale movements when walking through an aperture in the same way as their peers. The current study, therefore, considered perceptual judgements and motor behaviour of children with DCD while looking at or walking through apertures. Twenty-nine children with DCD and 29 typically developing (TD) children took part. In Experiment 1, participants completed a perceptual task, where they made passability judgements. Children with DCD showed a significantly smaller critical ratio (aperture size at which a participant first rotates the shoulders to pass through) compared to their TD peers. In Experiment 2, participants completed an action task where they walked through the same apertures. Children with DCD showed a significantly larger critical ratio than TD peers when body size alone was accounted for. Taken together these results suggest that perception within a static context is different from that within a dynamic context for children with DCD. However, despite this difference we have demonstrated a clear relationship between perception and action in children with DCD. A video abstract of this article can be viewed at: https://youtu.be/SABXFrAJtF8.

Adaptation and Extension of the European Recommendations (EACD) on Developmental Coordination Disorder (DCD) for the UK context.

BACKGROUND: Developmental Coordination Disorder (DCD) affects the learning and performance of everyday motor skills. It commonly co-occurs with other developmental disorders and a range of associated psycho-social impairments. Recent evidence-based guidelines on diagnosis, assessment, and intervention provide valuable information for practitioners. However these are directed primarily at German-speaking countries and focus on work with children. AIM: The aim of this project was to consider the application of these guidelines in the UK and to extend them for use with adults with DCD. METHODS: Individuals with DCD, parents, and professionals from a wide range of disciplines were invited to two workshops to discuss and debate the guidelines, to adapt them for the UK and produce dissemination materials. RESULTS: A working definition of DCD was agreed, minor revisions were made to the guidelines to reflect the UK context, an extension for adults was compiled and a series of leaflets was produced to disseminate this information to health and education professionals, parents, and employers. CONCLUSIONS: This work will raise awareness of the condition across different professional groups. It provides information to help those working with children and adults with DCD in the UK to assist in the process of diagnosis, assessment, and intervention.

Discovery of biomarkers for glycaemic deterioration before and after the onset of type 2 diabetes: rationale and design of the epidemiological studies within the IMI DIRECT Consortium.

AIMS/HYPOTHESIS: The DIRECT (Diabetes Research on Patient Stratification) Study is part of a European Union Framework 7 Innovative Medicines Initiative project, a joint undertaking between four industry and 21 academic partners throughout Europe. The Consortium aims to discover and validate biomarkers that: (1) predict the rate of glycaemic deterioration before and after type 2 diabetes onset; (2) predict the response to diabetes therapies; and (3) help stratify type 2 diabetes into clearly definable disease subclasses that can be treated more effectively than without stratification. This paper describes two new prospective cohort studies conducted as part of DIRECT. METHODS: Prediabetic participants (target sample size 2,200-2,700) and patients with newly diagnosed type 2 diabetes (target sample size ~1,000) are undergoing detailed metabolic phenotyping at baseline and 18 months and 36 months later. Abdominal, pancreatic and liver fat is assessed using MRI. Insulin secretion and action are assessed using frequently sampled OGTTs in non-diabetic participants, and frequently sampled mixed-meal tolerance tests in patients with type 2 diabetes. Biosamples include venous blood, faeces, urine and nail clippings, which, among other biochemical analyses, will be characterised at genetic, transcriptomic, metabolomic, proteomic and metagenomic levels. Lifestyle is assessed using high-resolution triaxial accelerometry, 24 h diet record, and food habit questionnaires. CONCLUSIONS/INTERPRETATION: DIRECT will yield an unprecedented array of biomaterials and data. This resource, available through managed access to scientists within and outside the Consortium, will facilitate the development of new treatments and therapeutic strategies for the prevention and management of type 2 diabetes.

Tailoring reach-to-grasp to intended action: the role of motor practice.

Motor learning results from repeated exposure to the same movement and allows a mover to increase movement optimality. Typically, this has only been considered in single-step movements. In sequential movements, an initial reach movement is tailored to the demands of the onward movement. However, the exact role of motor practice in the tailoring to onward task demands is unknown. Eighteen adults performed blocks of 15 movements; each movement consisted of a reach phase and an onward phase (the object was placed in a tight-fitting hole, placed in a loose-fitting hole or thrown). Simple practice effects were seen; for the reach phase, the amount of time spent decelerating decreased over trials, and for the onward phase, the accuracy of the place/throw movements increased over trials. Furthermore, approximately 30 % of variance in the practice effect of the onward phase could be explained by the practice effect in the reach phase. Therefore, we suggest that the changes in the reach phase are directly linked to the changes in the efficiency of action and that this is necessary but not sufficient for explaining the calibration of the onward action.

Corrigendum: Genome-wide association study of motor coordination.

[This corrects the article DOI: 10.3389/fnhum.2021.669902.].

To throw or to place: does onward intention affect how a child reaches for an object?

Picking up an object is a seemingly simple and isolated task; however, research has demonstrated that adults plan a reach-to-grasp movement on the basis of forthcoming actions. For example a greater deceleration period is seen in an initial reach movement which precedes a place movement compared to a throw movement. This task-specific or second-order motor planning is also seen in infants and toddlers; however, the developmental progression is unclear. Reach-to-grasp movements of 48 children, split into four age groups (4-5, 6-7, 8-9 and 10-11 years) were recorded. These movements preceded a tight place, a loose place or a throw action. All the children showed some degree of tailoring kinematics to the onward action. In the 4-5 year-old group, this was demonstrated by a longer movement duration in the place actions compared to the throw action. In the older children the proportion of time spent decelerating increased as the precision requirements of the task increased. These results demonstrate that all children are able to use second-order planning to integrate onward task demands into their movements. The capacity for this increases with age but is not fully mature at 11 years. These developmental effects may be explained by the relative weighting of costs involved in tailoring a reach action compared to the benefits of producing a more efficient onward action.

Relationships between motor skills and executive functions in developmental coordination disorder (DCD): A systematic review.

BACKGROUND: Individuals with developmental coordination disorder (DCD) experience motor skill and executive function (EF) difficulties that challenge their daily activities. AIM/OBJECTIVE: This systematic review aims to provide an in-depth analysis of the relationships between motor skills and EFs in studies among individuals with DCD. MATERIAL AND METHODS: We conducted a systematic search of eight electronic databases for articles (published 1994-2021) reporting on quantitative studies that estimated relationships between motor skills and EFs when assessing children, adolescents and adults with DCD. Motor skills and EFs were assessed via reliable and validated assessment tools. Two reviewers independently screened the articles. We evaluated the quality of the selected articles according to EPHPP guidelines and the methodological quality of the assessments from these studies using the COSMIN checklist and reported results following the PRISMA-P checklist. This systematic review was registered in PROSPERO (CRD42019124578). RESULTS: A total of 30,808 articles were screened. Eleven articles met the inclusion criteria and were reviewed. Findings from nine studies demonstrated weak to strong correlations between aspects of motor skills and EFs. CONCLUSIONS AND SIGNIFICANCE: Limited evidence supports the relationships between motor skills and EFs among individuals with DCD. Occupational therapists should consider the possibility of this relationship and give more consideration to these components when planning intervention for individuals with DCD.

Inhibition skills in children with developmental coordination disorder.

BACKGROUND: Inhibition (Response Inhibition - RI and Interference Control - IC) have been inconsistently examined in Developmental Coordination Disorder (DCD) with response modalities often not considered. AIMS: To examine RI and IC in children with DCD. METHOD: Twenty-five children 6-10 years with DCD, plus 25 matched typically developing peers completed motor and verbal RI and IC tasks. . RESULTS: Children with DCD made significantly more errors in the motor and verbal RI tasks, had slower movement time and RT in the motor IC task, and longer completion time in the verbal IC task. CONCLUSIONS: Children with DCD have RI and IC difficulties in motor and verbal responses.

Implementation of point-of-care HbA1C instruments into community pharmacies: Initial development of a pathway for robust community testing.

BACKGROUND: Point-of-care (POC) analysers in community settings can provide opportunistic and regular HbA1c monitoring. Community pharmacies in NHS Scotland are utilised by populations at greatest risk of type two diabetes (T2D). This study describes initial development of an HbA1c pathway using a POC analyser in community pharmacies. METHODS: The Abbott Afinion analyser was compared in (i) NHS Tayside's Blood Sciences Service and (ii) community pharmacies from four Scottish Health Boards. A side by side comparison with standard operating procedures for HbA1c quantification using 80 T2D patient venous samples. The machine was implemented into 11 community pharmacies and 144 samples obtained from patients for comparison to their recent laboratory HbA1c. Four focus groups examined themes around the intervention and an exit questionnaire was administered. RESULTS: Laboratory assessment verified the efficacy of the POC test machine. The value for level 1 quality control was 44 mmol/mol and the mean during testing 42.7 mmol/mol. The greatest percent coefficient of variation (cv) was within-run for both levels of quality control material, at a value of 1.63% and 1.62%, respectively. The analyser performed robustly within the pharmacy assessment, with a mean difference of 1.68 and a standard deviation of 0.71 (CV 0.423). Patients with T2D reported positive experiences of using a pharmacy. The focus groups identified an appreciation of the convenience of pharmacies and of the longitudinal relationships with pharmacy staff. CONCLUSION: POC HbA1c analysers can be successfully established in community pharmacies. The target patient group responded positively to the opportunity to use a pharmacy service.

Association of developmental coordination disorder with early-life exposure to fine particulate matter in Chinese preschoolers.

Although fine particulate matter (PM2.5) is a neurotoxicant, little is known about whether early-life PM2.5 exposure is associated with an increased risk of developmental coordination disorder (DCD). We conducted a cohort study of 109 731 children aged 3-5 years from 551 county-level cities in China between April 2018 and December 2019. Residential PM2.5 exposure was estimated using a hybrid satellite-based exposure model. Children's motor performance was assessed using the Little DCD Questionnaire (LDCDQ). Linear mixed-effect models and generalized linear mixed models with a binomial distribution were used to examine the associations of PM2.5 exposure with LDCDQ scores and risk of DCD, respectively. Both prenatal and postnatal exposure to a higher level of PM2.5 was significantly associated with reduced total LDCDQ score, and the impacts were evident on subscales of control during movement and general coordination function but not fine motor function. For example, an interquartile range increase in PM2.5 exposure in ages 0-3 was associated with a 0.19 (95% confidence interval [CI]: 0.05, 0.33) decrement in the total score. Additionally, higher PM2.5 exposure was associated with increased risk of DCD, and the adjusted odds ratios were 1.06 (95% CI: 1.01, 1.10) and 1.06 (95% CI: 1.01, 1.13) for each interquartile range increase in PM2.5 exposure during the first trimester and the first 3 years, respectively. Children who were from rural areas, had neonatal intensive care unit admission, or were exclusively breastfed for less than 6 months appeared to be more susceptible to PM2.5 exposure than their counterparts. Our findings provide robust evidence that early-life PM2.5 exposure contributes to an elevated risk of DCD.

Handwriting legibility across different writing tasks in school-aged children.

Background: In school, children are required to perform a range of handwriting tasks. The writing needs to be legible to the child and other readers. The aim of this study was to examine handwriting legibility across different writing tasks and to explore which components might predict overall handwriting legibility. Methods: This was a secondary analysis of data from 148 school-aged children across writing scripts obtained from the Detailed Assessment of Speed of Handwriting: copying-best, copying-quickly and free-writing. Results: Results showed that letter formation was the major predictor of the total HLS score, and significant differences in handwriting legibility were found across the three tasks. Conclusions: The HLS is a practical tool that can benefit occupational therapists who work in schools by assessing handwriting legibility across different handwriting tasks.

Inter-limb coordination in a novel pedalo task: A comparison of children with and without developmental coordination disorder.

Children with Developmental Coordination Disorder (DCD) have been shown to have different coordination patterns on some tasks compared to their typically developing peers. However, it is unclear whether these differences are driven by the fact that typically developing children tend to be more practiced at the task on which coordination is being measured. The current study used a novel pedalo task to measure coordination in order to eliminate any practice differences. Thirty children (8 years -16 years), 15 with DCD and 15 without were recruited for this study. Children pedalled along an 8 m line 20 times. Movement of the 7th Cervical Vertebra, shoulders, elbows, wrists, hips, knees, ankles and toes was recorded. In terms of outcome measures, pedalling speed was not different between the groups but the coefficient of variation of speed was higher in the children with DCD indicating a less smooth movement. Coordination was measured by calculating angles at the shoulder, elbow, hip, knee and ankle. A higher correlation coefficient (more tightly coupled movement) and a greater variation in joint angle was seen in the typically developing children for specific joint segments. The relationship between group and movement outcome (smoothness of movement) was mediated by inter-limb coordination variability. Therefore, the poor coordination and slower learning generally reported in children with DCD could be due to a slower or less optimal exploration of motor solutions.

Association of the Onset of Self-Feeding With Subsequent Suspected Developmental Coordination Disorder: A Prospective Cohort Study in China.

Background: Successful self-feeding reflects the readiness of early motor development and environmental impacts, and the onset of self-feeding as a developmental milestone might be a predictor of subsequent motor development in children. In this study, we explored the association between the onset of self-feeding and childhood risk of Developmental Coordination Disorder in children from one-child and two-child families. Methods: We conducted a data-linkage prospective cohort study from 38 kindergartens in 6 cities in China. A total of 11,727 preschoolers aged 3-6 years old were included in the final analysis and were assessed with the Movement Assessment Battery for Children-second edition (MABC-2) Test. The information on early self-feeding onset was obtained from parents. The mixed and multi-level logistic models utilizing a random intercept were used to investigate the associations between the onset time of self-feeding and subsequent motor performance. Results: The results showed that, compared with those beginning self-feeding at or younger than 12 months of age, children starting self-feeding at 13-24, 25-36, and later than 36 months, showed a decrease in their total MABC-2 scores of 2.181, 3.026, and 3.874, respectively; and had an increased risk of suspected DCD by 36.0, 101.6, 102.6%, respectively; they also had 30.2, 46.6, 71.2% increased prevalence of at risk of suspected DCD, when adjusting for both child and family characteristics (each p < 0.05). Significant associations were observed in fine motor, gross motor, and balance subtests (each p < 0.05) in groups with a delayed onset of self-feeding. However, the strength of the associations was mitigated in the fine motor and balance subtests in children with a sibling. Conclusion: The delayed onset time of self-feeding acts as an early behavioral marker for later childhood motor impairment. Moreover, children with a sibling may benefit from additional interaction and their motor developmental pattern may be affected by the presence of a sibling.

Association of Gestational Age at Birth With Subsequent Neurodevelopment in Early Childhood: A National Retrospective Cohort Study in China.

Background: The association between preterm birth and neurodevelopmental delays have been well examined, however, reliable estimates for the full range of gestational age (GA) are limited, and few studies explored the impact of post-term birth on child development. Objective: This study aimed to examine the long-term neuropsychological outcomes of children born in a full range of GA with a national representative sample in China. Methods: In this retrospective population-based cohort study, a total of 137,530 preschoolers aged 3-5 years old (65,295/47.5% females and 72,235/52.5% males) were included in the final analysis. The Ages and Stages Questionnaires-Third Edition (ASQ-3) was completed by parents to evaluate children's neurodevelopment. The associations between GA and neurodevelopment were analyzed by a generalized additive mixed model with thin plate regression splines. Logistic regression was also conducted to examine the differences in children's development with different GAs. Results: There was a non-linear relationship between GA and children's neurodevelopmental outcomes with the highest scores at 40 weeks gestational age. The adjusted risks of GAs (very and moderately preterm, late-preterm, early-term, and post-term groups) on suspected developmental delays were observed in communication (OR were 1.83, 1.28, 1.13, and 1.21 respectively, each p < 0.05), gross motor skill (OR were 1.67, 1.38, 1.10, and 1.05 respectively, each p < 0.05), and personal social behavior (OR were 1.01, 1.36, 1.12, and 1.18 respectively, each p < 0.05). The adjusted OR of very and moderately preterm, late-preterm, and early-term were observed in fine motor skills (OR were 1.53, 1.22, and 1.09 respectively, each p < 0.05) and problem-solving (OR were 1.33, 1.12, and 1.06 respectively, each p < 0.05). Conclusion: GAs is a risk factor for neurodevelopmental delays in preschoolers after controlling for a wide range of covariates, and 40-41 weeks may be the ideal delivery GA for optimal neurodevelopmental outcomes. Close observation and monitoring should be considered for early- and post-term born children as well as pre-term children.