Sibship Composition and BMI Z-Score Among Saudi Preschoolers: A Cross-Sectional Study.

Background and objective The association between sibship composition and child body mass index (BMI) has not been investigated in any Arab/Middle Eastern populations. In light of this, this study aimed to examine the association of the number of siblings, number of older siblings, and number of younger siblings with child BMI z-score (BMIz) among preschoolers in the Kingdom of Saudi Arabia (KSA). Methods A total of 209 mothers and their children were recruited from preschools in Jeddah, KSA. Mothers reported their responses to the study questionnaire via telephone. Child anthropometry was objectively measured; BMIz was calculated based on age- and sex-specific World Health Organization (WHO) growth standards and reference data. We used hierarchical multiple linear regression to examine the association between sibship composition variables and child BMIz, independent of the effect of potential confounders, and to evaluate changes in model fit. Results The number of siblings was negatively associated with child BMIz [b = -0.18, 95% confidence interval (CI) = -0.35, -0.06, p<0.01, adjusted R2 = 0.16]. There was a negative association between the number of older siblings and child BMIz (b = -0.23, 95% CI = -0.38, -0.11, p<0.01, adjusted R2 = 0.21) as well as between the number of older sisters and child BMIz (b = -0.18, 95% CI = -0.52, -0.09, p<0.01, adjusted R2 = 0.19). However, there were no significant associations between the number of older brothers or the number of younger siblings and child BMIz. Conclusions Based on our findings, sibship composition was found to be associated with BMIz among a sample of preschoolers in KSA. More research is needed to further establish this association and to understand the underlying mechanism of the association of the greater number of older siblings and older sisters with lower BMIz.

Reliability and validity of rapid assessment tools for measuring 24-hour movement behaviours in children aged 0-5 years: the Movement Behaviour Questionnaire Baby (MBQ-B) and child (MBQ-C).

BACKGROUND: The development of validated "fit-for-purpose" rapid assessment tools to measure 24-hour movement behaviours in children aged 0-5 years is a research priority. This study evaluated the test-retest reliability and concurrent validity of the open-ended and closed-ended versions of the Movement Behaviour Questionnaire for baby (MBQ-B) and child (MBQ-C). METHODS: 300 parent-child dyads completed the 10-day study protocol (MBQ-B: N = 85; MBQ-C: N = 215). To assess validity, children wore an accelerometer on the non-dominant wrist (ActiGraph GT3X+) for 7 days and parents completed 2 × 24-hour time use diaries (TUDs) recording screen time and sleep on two separate days. For babies (i.e., not yet walking), parents completed 2 × 24-hour TUDs recording tummy time, active play, restrained time, screen time, and sleep on days 2 and 5 of the 7-day monitoring period. To assess test-retest reliability, parents were randomised to complete either the open- or closed-ended versions of the MBQ on day 7 and on day 10. Test-retest intraclass correlation coefficients (ICC's) were calculated using generalized linear mixed models and validity was assessed via Spearman correlations. RESULTS: Test-retest reliability for the MBQ-B was good to excellent with ICC's ranging from 0.80 to 0.94 and 0.71-0.93 for the open- and closed-ended versions, respectively. For both versions, significant positive correlations were observed between 24-hour diary and MBQ-B reported tummy time, active play, restrained time, screen time, and sleep (rho = 0.39-0.87). Test-retest reliability for the MBQ-C was moderate to excellent with ICC's ranging from 0.68 to 0.98 and 0.44-0.97 for the open- and closed-ended versions, respectively. For both the open- and closed-ended versions, significant positive correlations were observed between 24-hour diary and MBQ-C reported screen time and sleep (rho = 0.44-0.86); and between MBQ-C reported and device-measured time in total activity and energetic play (rho = 0.27-0.42). CONCLUSIONS: The MBQ-B and MBQ-C are valid and reliable rapid assessment tools for assessing 24-hour movement behaviours in infants, toddlers, and pre-schoolers. Both the open- and closed-ended versions of the MBQ are suitable for research conducted for policy and practice purposes, including the evaluation of scaled-up early obesity prevention programs.

Evaluation of the association between excessive screen use, sleep patterns and behavioral and cognitive aspects in preschool population. A systematic review.

In this review, we analyzed the possible relationship between the excessive use of screens and sleep patterns, and how this may affect certain behavioral and cognitive factors in preschool children. The selection, extraction and synthesis of the data were conducted according to PRISMA guidelines. The search was carried out in the electronic databases Medline (PubMed), PsycINFO (American Psychological Association), Scopus and Web of Science (WOS). Of the 597 articles initially identified, 13 met the inclusion criteria. The risk of bias of the articles selected was evaluated using a specific scale created for this purpose. The results found indicate that excessive use of screens is associated with a negative impact on the duration and quality of sleep-in preschoolers, and this worsening of sleep in infancy is related with a greater probability of the appearance of internalizing and externalizing behavioral problems and certain cognitive problems. The results also suggest that sleep could play a mediating or moderating role as a bioregulatory system that attenuates or increases the onset of behavioral and cognitive difficulties in those children most exposed to digital devices.

Comparison of Global and Daily Ratings of Associations between Anxiety and Depressive Behaviors and Impairment in Preschool-Aged Children.

Anxiety and depressive difficulties can emerge during early childhood and cause impairment in functioning. Anxiety and depressive behaviors and impairment are typically assessed with global questionnaires that require recall of children's behavior over an extended period which could reduce the accuracy of parent report of children's behavior and functioning. The current study compared parents' report of children's anxiety and depressive behaviors and impairment when evaluated with global measures versus a daily diary measure. Participants (N = 901 parents of 3-5-year-old children) completed global and daily measures of children's behavior and impairment during enrollment to the study. Global measures were completed at baseline and the 14 daily diary measures were completed consecutively for two weeks. Across most measures, daily associations between parent-reported anxiety and depressive behaviors and impairment were stronger compared to associations with global measures. These results suggest that daily measures may better capture links between young children's typical behavior and functioning compared to global measures. In addition, daily assessment might be more effective for measuring mild to moderate yet still impairing behaviors that may be missed on global reports that require longer periods of recall.

The Associations Between Parental-Reported and Device-Based Measured Outdoor Play and Health Indicators of Physical, Cognitive, and Social-Emotional Development in Preschool-Aged Children.

PURPOSE: Examine in preschool-aged children: (1) the associations between parental-reported and device-measured outdoor play (OP) and health indicators of physical, cognitive, and social-emotional development and (2) whether associations were independent of outdoor moderate- to vigorous-intensity physical activity (MVPA). METHODS: This cross-sectional study included 107 participants. Children's OP was measured via a parental questionnaire and the lux feature of accelerometers. Children's growth, adiposity, and motor skills were assessed as physical development indicators. Visual-spatial working memory, response inhibition, and expressive language were assessed as cognitive development indicators. Sociability, prosocial behavior, internalizing, externalizing, and self-regulation were assessed as social-emotional development indicators. Regression models were conducted that adjusted for relevant covariates. Additional models further adjusted for outdoor MVPA. RESULTS: Parental-reported total OP, OP in summer/fall months, and OP on weekdays were negatively associated (small effect sizes) with response inhibition and working memory. After adjusting for outdoor MVPA, these associations were no longer statistically significant. OP on weekdays was negatively associated with externalizing (B = -0.04; 95% confidence interval, -0.08 to -0.00; P = .03) after adjusting for outdoor MVPA. A similar pattern was observed for device-based measured total OP (B = -0.49; 95% confidence interval, -1.05 to 0.07; P = .09). CONCLUSIONS: Future research in preschool-aged children should take into account MVPA and contextual factors when examining the association between OP and health-related indicators.

Longitudinal Changes in Refractive Development in Highly Hyperopic Children: A 2.6-11.2 Year Follow-up of Preschoolers Diagnosed with High Hyperopia.

PURPOSE: This study aims to elucidate the longitudinal refractive and ocular biometric alterations in preschool children with high hyperopia who underwent early interventions. METHODS: We conducted a retrospective analysis of preschool children diagnosed with high hyperopia at Tianjin Medical University Eye Hospital between 2011 and 2023. Inclusion criteria required an initial examination with cycloplegic refraction, bilateral spherical equivalent power (SE) ≥ +5.00D with a difference <1.00D, a minimum two-year follow-up, and at least three ocular biometric measurements. The annual axial growth rate evaluated emmetropization in highly hyperopic children. We applied Restricted Cubic Spline (RCS) models to explore potential nonlinear relationships between age and spherical equivalent, axial length, corneal curvature, and axial length-to-corneal curvature ratio. Additionally, Mixed-effects models were employed to investigate factors associated with changes in refractive error and axial length. RESULTS: The study enrolled 60 eligible subjects, with a median initial diagnosis age of 3.5 years (IQR, 2.8-4.9 years) and a median last visit age of 9.3 years (IQR, 8.1-10.8 years). The average follow-up duration was 5.7 years. RCS analysis revealed notable nonlinear changes in spherical equivalent power, axial length, and axial length-to-corneal curvature ratio, although corneal curvature displayed no statistically significant nonlinear trend. Factors affecting SE changes included the presence of strabismus, the use of cycloplegia, baseline SE, and age. Conversely, changes in axial length solely correlated with baseline axial length and age. CONCLUSION: Highly hyperopic preschool children undergoing early intervention display a marked emmetropization tendency, though most still remain moderately to highly hyperopic, with the progression of refractive changes showing non-uniform patterns with respect to age.

Association between parental feeding styles, body mass index, and consumption of fruits, vegetables and processed foods with mothers´ perceptions of feeding difficulties in children.

BACKGROUND: Feeding difficulties (FDs) are complex phenomena influenced by parental factors, feeding behaviour, and cultural factors. However, studies of the influences of these factors on FDs incidence are scarce. Thus, this study aimed to identify the associations between mothers' perceptions of FDs in children and parental feeding styles, body mass index, and the consumption of fruits, vegetables and processed foods. METHOD: Two hundred and fifty-seven mothers of children aged 1 to 6 years and 11 months participated in this cross-sectional study and self-completed electronic questionnaires on sociographic variables, parental feeding styles, the consumption of fruits, vegetables and processed foods and FDs. Nutritional status was classified by body mass index (kg/m2). RESULTS: The prevalence of FDs in children was 48.2%, and the mean age was 43.8 (± 17.6) months. The indulgent parental feeding style was the most common (40.1%), followed by the authoritative (31.1%), authoritarian (23.7%), and uninvolved (5.1%) styles. An indulgent parental feeding style (OR: 4.66; 95% CI: 2.20-9.85), a high body mass index (OR: 1.35; 95% CI: 1.09-1.68), and the consumption of processed foods (OR: 5.21; 95% CI: 2.85-9.53) were positively associated with increased odds of the absence of FDs in children. The associations of authoritarian and uninvolved parental feeding styles and the consumption of fruits and vegetables with FDs in children were not significant. CONCLUSION: This study identified multiple factors that are possibly associated with feeding behaviours in young children. However, further studies need to be undertaken to evaluate how such behaviours affect FDs.

Acquisition pattern and the role of vocabulary and language experience in the acquisition of inflectional grammar by Mandarin-English speaking preschoolers.

Australian Mandarin-English bilingual preschoolers must acquire linguistic structures that occur only in the community language (e.g., English inflectional grammar). This study investigated how they acquire such structures and any relationship between linguistic knowledge and language experience on their performance. Twenty 4-6-year-olds showed known monolingual acquisition patterns with good performance for producing the progressive, developing ability for plurals, but only emerging ability for past and present tense. Better performance was related to a larger English vocabulary, more mixed language input and use, but less Mandarin input and use. On average, these children received less than 50% input in English and were performing behind monolinguals.

Meeting the 24-h movement recommendations and its relationship with Mediterranean dietary patterns in early childhood: the SENDO project.

The aim of this study was twofold: (1) to assess the association between meeting all three 24-h movement recommendations and adherence to the Mediterranean diet (MedDiet) in early childhood and (2) to examine whether participants who meet all three 24-h movement recommendations have greater adherence to the individual MedDiet foods/components than those who do not meet these recommendations. A cross-sectional study was conducted using a sample of 822 participants from the Seguimiento del Niño para un Desarrollo Óptimo (SENDO) project (Pamplona, Spain). Physical activity was assessed through a questionnaire that covered 17 different types of activities. Screen time was assessed by averaging the daily hours spent on activities such as watching TV, using a computer, or playing video games. Sleep duration was determined by taking the average of sleep durations during both weekdays and weekends. Adherence to the MedDiet was evaluated using the Mediterranean Diet Quality Index in children and adolescents (KIDMED). Greater odds of having an optimal adherence to the MedDiet were found for participants meeting all three 24-h movement recommendations (odds ratio (OR) = 1.96, 95% confidence interval (CI) 1.33-2.87, p = 0.001) in comparison with their counterparts not meeting these recommendations. Specifically, significant differences were found for "fruit or fruit juice every day" (p = 0.012), "second fruit every day" (p = 0.001), and "fresh or cooked vegetables regularly once a day" (p = 0.018) in relation to meeting all three 24-h movement recommendation status.    Conclusions: This study provides further evidence of the potential importance of meeting all three 24-h movement recommendations to adopt a healthier eating pattern. What is Known: • Only a limited number of studies have investigated the joint connection between the 24-h movement recommendations and dietary habits. • Integrating the 24-h movement recommendations with dietary recommendations could potentially yield greater effectiveness compared to promoting these recommendations independently within public health strategies. What is New: • This is the first study in assessing the relationship between 24-h movement recommendations and adherence to the Mediterranean diet in early childhood. • These findings provide further evidence of the potential importance of meeting all three 24-h movement recommendations to adopt a healthier eating pattern.

The Hidden Impact of ADHD Symptoms in Preschool Children with Autism: Is There a Link to Somatic and Sleep Disorders?

Neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), do often present in comorbidity among them and with other medical conditions, including sleep and gastrointestinal (GI) disorders and somatic complaints. An anonymous online survey based on standardized questionnaires (SDSC, KL-ASD, APSI, ROME V CRITERIA, CPRS, CBCL) was completed by the parents of 46 preschoolers diagnosed with ASD. A high prevalence (47%) of ADHD symptoms in this population was found, surpassing previous estimates. Sleep disturbances, especially difficulties in initiating and maintaining sleep and sleep-wake transition, are more pronounced in ASD patients with comorbid ADHD. Additionally, in patients over 4 years old, there is a high prevalence of functional GI symptoms (Rome V criteria: 38%). Parental stress is significantly associated with ADHD symptoms, sleep disorders, and GI symptoms. Comprehensive assessments considering both core symptoms of neurodevelopmental disorders and associated comorbidities are crucial for more effective treatment strategies and improved wellbeing in affected individuals and their families.

What Factors Predict Adaptive Functioning in Preschool Children with Autism Spectrum Disorder? A Longitudinal Study.

Adaptive functioning constitutes a fundamental aspect of the phenotype associated with autism spectrum disorder (ASD) in preschool-aged children, exerting a significant influence on both the child and the family's overall quality of life. The aim of this study was to investigate the predictors of the adaptive functioning domains in preschool-age children with ASD at two time points, providing a snapshot of this fundamental developmental step. Methods: Ninety-five children with ASD (M = 3.89, SD = 1.13) were included in the study and longitudinal data (the mean length of the longitudinal data collection was 1 year) on ASD features such as social communication and social interaction, repetitive and restricted behavior, cognitive level, and adaptive functioning were collected. We considered autistic features, cognitive level, and sociodemographic factors as possible predictors of the different adaptive functioning domains one year later. Results: Data obtained showed a worsening of the ASD features and adaptive functioning after one year. Furthermore, the severity of repetitive and restricted behavior predicted adaptive functioning, especially in the social and practical domains of the child, one year later. This prediction was observed alongside the child's cognitive level. Conclusions: The study identifies some potential predictive factors of specific adaptive functioning domains in preschoolers with ASD. Considering how critical adaptive functioning is for the well-being of both the child and their family, it becomes imperative to design early-stage interventions focused on nurturing adaptive skills in children with ASD.

24-H movement behaviors and physical fitness in preschoolers: A compositional and isotemporal reallocation analysis.

Background/Objectives: This study examined the relationships between 24-h movement behaviors and physical fitness (PF) in preschool children. Methods: The study was conducted on 474 children aged 3-6 years in Zhuhai. Physical activity (PA) and sedentary behavior (SB) were collected by the accelerometer, and sleep time was assessed through the parent-report questionnaire. Balance, cardiorespiratory fitness (CRF), flexibility, muscle strength, muscular endurance, and speed-agility were measured using a balance beam test, 20 m shuttle run test, sit and reach test, handgrip test, sit-ups, and 4 × 10 m shuttle run test respectively. The compositional data analysis was used to examine the association between 24-h movement behaviors and PF, and the compositional isotemporal substitution analysis was used for the time reallocation. Results: The daily composition, adjusted for age, gender, and body mass index (BMI), was significantly associated with CRF (p < 0.001, r2 = 0.20), flexibility (p < 0.001, r2 = 0.07), muscular strength (p < 0.001, r2 = 0.37), muscular endurance (p < 0.001, r2 = 0.26), and speed-agility (p < 0.001, r2 = 0.26). The addition of moderate-to-vigorous PA (MVPA) at the expense of SB and sleep, MVPA at the cost of sleep, was associated with significant muscular strength and speed-agility improvements respectively. The impact of SB and sleep replacing MVPA is stronger than MVPA replacing SB and sleep on muscular strength. Conclusion: These findings offer useful insight for the replacement of movement behaviors within the recommended range to facilitate PF development in early childhood.

Reduction of haemoglobin is related to metal mixtures exposure in Chinese preschoolers: Joint effect models.

Heavy metal exposure is a known risk factor for hematologic disorders in children, yet the impact of co-exposure to multiple metals remains underexplored. This cross-sectional study investigates the relationship between urinary levels of 23 metals and haemoglobin (Hb) in 1460 Chinese preschoolers. The concentrations of the 23 urinary metals were quantified using an inductively coupled plasma mass spectrometer, while Hb levels were assessed through finger prick blood samples. To evaluate the co-exposure effects, we employed three approaches: Generalized linear regression model, joint effect models including Quantile g-Computation and Bayesian Kernel Machine Regression (BKMR). From the generalized linear regression and Quantile g-computation, urinary uranium, thallium, aluminium, iron and tungsten were correlated negatively with Hb, while urinary barium was correlated positively (all P < 0.05). Moreover, significant negative associations between metal mixtures exposure with Hb were identified in both Quantile g-computation [ß (95% CI): -0.083 (-0.132, -0.033), P = 0.0012] and BKMR [90th percentile vs. 50th percentile ß (95% CI): -0.238 (-0.368, -0.107), P < 0.001] with aluminium emerging as the primary contributor to this joint effect (weight in Quantile g-computation = 0.399, PIPs in BKMR = 0.896). These findings provide a potential explanation for environmental exposure to metals and Hb-related disease in preschoolers.

Substituting Book Reading for Screen Time Benefits Preschoolers' Sleep Health: Results from the Ulm SPATZ Health Study.

Purpose: Healthy sleep is essential for the physical, cognitive, and social development of children. Several studies have reported the increase in digital media use in preschool children and its association with impaired sleep. However, there is relatively little evidence on the effects of book reading as a potentially safe alternative. The objective of this study, therefore, was to investigate whether sleep in children could benefit from book reading, and whether the negative effects of media use on sleep can be mitigated by substituting book reading for screen time. Participants and Methods: We used longitudinal data from three consecutive waves of the SPATZ Health study, including children at the ages of 4 (n=581), 5 (n=508), and 6 (n=426) years. All data were collected by self-administered questionnaires. Parent-reported child sleep was assessed by the Children's Sleep Habits Questionnaire. Results: Across the three waves, screen-based media use increased and was associated with lower sleep quality. In contrast, the time spent with book reading decreased; however, book reading appeared to be beneficial for children's sleep. Substitution models revealed that the theoretical substitution of an equal amount of book reading for 50% of the time spent with screen-based media benefits several domains of preschoolers' sleep health, including parasomnias, sleep anxiety, daytime sleepiness, and sleep onset delay. Conclusion: Besides implications for population-wide and individual prevention, book reading may also be incorporated as a useful intervention to improve sleep quality in children who are already affected by sleep problems. Given that book reading is perceived as a safe alternative, the presented evidence may suffice to support recommendations in this direction.

The validity of learning potential for predicting educational adjustment in preschoolers with Down syndrome: A longitudinal study.

Learning Potential tests aim to assess cognitive functioning using mediation strategies by observing subsequent changes in learning patterns. In this study, this methodology was applied with the Preschool Learning Potential and Abilities Scale and two additional tests, the Kaufman Brief Intelligence Test and the Battery of Aptitudes for School Learning I, to a total of 58 children with Down Syndrome, at four and six years of age. The results demonstrate improvements in general intelligence, learning potential, and school aptitudes between the two timepoints. There was a significant, positive relationship between the variables measured in the different tests, as well as on the predictive variables of school aptitudes, in these children at six years of age. There is evidence that supports the use of this dynamic evaluation methodology, opening new fields of action in child evaluation processes.

Normative values of motor performance and their relationship with BMI status in Hong Kong preschoolers.

This study aimed to establish sex- and age-specific reference values for motor performance (MP) in Hong Kong preschoolers aged 3-5 years old and examine the relationship between MP and BMI status. A cross-sectional study was conducted among 5579 preschoolers in Hong Kong. Three MP tests were administered, and height and weight information were collected. GAMLSS was used to compute the normative values of the motor tests. Boys outperformed girls in activities requiring muscle strength and power, while girls outperformed boys in activities requiring balance and coordination. The MP scores increased with age for both overarm beanbag throw and standing long jump for both sexes, while the one-leg balance scores showed larger differences between P50 and P95 in older preschoolers. Children with excessive weight performed worse in standing long jump and one-leg balance compared to their healthy weight peers. This study provides valuable information on the MP of preschoolers in Hong Kong, including sex- and age-specific reference values and the association between BMI status and MP scores. These findings can serve as a reference for future studies and clinical practice and highlight the importance of promoting motor skill development in preschoolers, particularly those who are overweight or obese.

Novel Insights into Obesity in Preschool Children with Autism Spectrum Disorder.

Obesity is present in 8-32% of the children with Autism Spectrum Disorder (ASD). However, most studies are performed in school-aged children from the USA. The current study compares obesity rates of Dutch preschoolers with ASD with children from the Dutch general population and explores which child- and parental factors are related to obesity in children with ASD. This cross-sectional study is part of the ongoing Tandem Study (Dutch Trial register: NL7534). Seventy-eight children with ASD aged 3-7 years and their parents (77 mothers, 67 fathers) participated. Child factors are: Body Mass Index (by physical measurement), child eating behavior (Child Eating Behavior Questionnaire), child problem behavior (Child Behavior Checklist), and ASD severity (Autism Diagnostic Observation Scale 2). Parental factors are: BMI (by physical measurement), parental eating behavior (Dutch Eating Behavior Inventory), parenting stress (The Parenting Stress Questionnaire) and highest completed educational level (SES). Children with ASD were 8 times more often obese (16.8%) than children from the general population (2.0%). Child BMI correlated positively with child food approach behavior and maternal BMI, and correlated negatively with child 'Slowness in eating'. There was no correlation between child BMI and ASD severity, problem behavior, parental eating behavior, parental stress and SES. Thus, Dutch, preschool children with ASD have 8 times higher obesity rates than children from the general population. More attention to obesity risk in research and clinical care could contribute to the quality of life of individuals with ASD and their families. CLINICAL TRIAL REGISTRATION: Dutch Trial register, NL7534, https://trialsearch.who.int/Trial2.aspx?TrialID=NL7534 .

Relationship between bedtime, nighttime sleep duration, and anxiety symptoms in preschoolers in China.

Background: Sleep problems in preschoolers are becoming increasingly prominent, and the association between sleep status and anxiety symptoms has attracted growing attention. However, studies investigating the relationship between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms remain scant. We used the large sample data from the Longhua Cohort Study of Children in Shenzhen, China (LCCS) to analyze the association between bedtime and sleep in preschoolers and their anxiety symptoms. Methods: A cross-sectional study of 69,138 preschoolers in Longhua District, Shenzhen, China was conducted in 2022. Data on sociodemographic characteristics of families, bedtime, nighttime sleep duration of preschoolers, and their anxiety symptoms (measured by the Spence Preschool Children Anxiety Scale) were collected through a structured questionnaire completed by the parents. Using binary logistic regression models, the relationship between bedtime, nighttime sleep duration, and childhood anxiety symptoms was examined. Results: The bedtimes of preschoolers were concentrated between 21:01-22:00 (52.41%). Among the preschoolers, 38.70% had bedtimes later than 22:00, and 75.49% had insufficient nighttime sleep duration. The positive screening rate for anxiety symptoms among preschoolers was 3.50%. After adjusting for confounding factors using binary logistic regression models, compared with preschoolers with bedtime ≤21:00, The OR (95%CI) values of anxiety in preschoolers with bedtime ≥23:01, 22:01-23:00 and 21:01-22:00 were 2.86 (2.21-3.69), 1.51 (1.27-1.79) and 1.48 (1.26-1.76), respectively. Compared with those with sufficient nighttime sleep duration, the OR (95%CI) of children with nighttime sleep duration less than 9 h was 1.36 (1.23-1.51). Conclusion: An association exists between bedtime and nighttime sleep duration in preschoolers and their anxiety symptoms. Preschoolers with 21:00 for bedtime and a nighttime sleep duration of 10 h may have lower anxiety symptoms. These findings support the importance of adequate sleep for preventing anxiety symptoms in children.

Sleep and Technology in Early Childhood.

Research suggests that technology use is associated with poorer sleep outcomes among children less than 6 years of age. These associations are evident regardless of the type of technology studied, although evening exposure may have the greatest impact compared with technology use during other parts of the day. More work is needed, particularly given that technology use is relatively high among young children. Clinicians should assess patients' technology exposure, including before bedtime, to assess whether sleep issues stem from children's technology use. Moreover, clinicians should educate caregivers about the association between technology use and sleep problems among young children.

Assessing the usefulness of the Little Developmental Coordination Disorder Questionnaire-Chinese in Chinese preschoolers: a sex-and age-specific analysis.

Aim: This study evaluated the sex-and age-specific usefulness of the Little Developmental Coordination Disorder Questionnaire-Chinese (LDCDQ-CH) in Chinese preschoolers. Method: A population-based sample of 51,110 children aged 3-5 years was recruited. Internal reliability, construct validity, concurrent validity with the Ages and Stages Questionnaire-third edition (ASQ-3), and discriminant validity with the Movement Assessment Battery for Children-second edition (MABC-2) were assessed. Age and sex effects on LDCDQ-CH scores were analyzed using ANOVA and t-tests. Results: The LDCDQ-CH exhibited excellent internal consistency and reliability across ages and genders. Confirmatory factor analysis supported the 15-item model's satisfactory fit. Positive and significant correlations were observed between LDCDQ-CH and ASQ-3 scores, indicating robust concurrent validity. Significant associations were found between LDCDQ-CH and MABC-2 scores. Higher scores were observed in older children and girls, indicating age- and sex-related differences in motor functional performance. Conclusion: The LDCDQ-CH is a reliable and valid tool to support early identification of motor coordination difficulty in Chinese preschoolers, and guiding interventions. Findings support its use across ages and genders, highlighting its potential in the Chinese context. Age- and sex-specific norms are needed for enhanced clinical applicability.