Measuring sleep in young children and their mothers: Identifying actigraphic sleep composites

Day-to-day bidirectional associations between sleep and emotion states in early childhood: Importance of end-of-day mood for sleep quality

OBJECTIVES

Poor quality sleep can impact emotions and emotion regulation, resulting in a "sleep-mood" cycle where poor sleep affects mood and vice-versa. This relationship is poorly understood during early childhood, when sleep patterns and emotion displays are rapidly changing. This study aimed to understand the day-to-day effects of poor sleep on emotions in preschoolers by using objective (actigraphy) and subjective (ecological momentary assessment) measures to assess both between- and within-child effects. We hypothesized that disrupted sleep would lead to affect disruptions and vice versa.

METHODS

This study included 133 preschoolers and their caregivers recruited from the community. Children's sleep was measured via actigraphy (ActiGraph GT3X+) across 1week. Affect was collected concurrently via caregiver report during an ecological momentary assessment protocol. Caregivers reported on their child's affect four times per day: morning, afternoon, early evening, and before bed.

RESULTS

Multilevel modeling analyses revealed that children with sleep disturbances displayed less positive affect overall, more negative affect in the evenings, and alterations in positive affect lability, and that daytime affect was associated with subsequent nighttime sleep. Within-child associations also showed fluctuations in positive affect correlated with shorter sleep durations and later bedtimes.

CONCLUSIONS

This study identified both between- and within-child associations between sleep and affect in early childhood, revealing a dynamic and reciprocal relationship between the two. These findings highlight the importance of considering both sleep and affect in early childhood interventions, as promoting positive affect may enhance sleep quality and vice versa.

Exploring the Relationship Between Age at Nap Cessation and Social-Emotional Functioning in Children

OBJECTIVE

The objective of this study was to examine variations in age at nap cessation and identify whether there is an association with social-emotional functioning (SEF) as measured by internalizing/externalizing behavior, child temperament, and social skills in a sample of early childhood education and care-attending children.

METHODS

The sample comprised 1117 children from the Australian Effectiveness Early Educational Experiences for Children longitudinal early childhood study. We used children's age at nap cessation as retrospectively recalled by caregivers in 2011 or 2013 when children were between ages 2 and 7 years. Each child's SEF was reported by a caregiver using the Strengths and Difficulties Questionnaire, the Short Temperament Scale for Children, and the Social Skills Inventory Scale. Associations between children's age of nap cessation and SEF were tested using linear regressions.

RESULTS

The children's age at nap cessation ranged from 6 months to 6 years. For each additional year of napping, children's total , conduct , externalizing , and peer behavior problems decreased by 0.39 (95% confidence interval [CI], -0.70 to -0.09), 0.11 (95% CI, -0.21 to -0.01), 0.11 (95% CI, -0.51 to -0.06), and 0.11 (95% CI, -0.20 to -0.02) units on the Strengths and Difficulties Questionnaire scale, respectively. No further significant associations were found.

CONCLUSION

This is the first study reporting the age range of nap cessation and its associations with social-emotional functioning. Our findings demonstrate earlier cessation ages in Australian children attending Early Childhood Education and Care programs than previously reported and a small association with externalizing and peer problems.

A multimethod evaluation of bed provision and sleep education for young children and their families living in poverty

STUDY OBJECTIVES

We evaluated the impact of bed provision and sleep education through the Beds for Kids (BfK) program on early childhood sleep and behavior and maternal mood and sleep.

METHODS

Twenty-seven mother-child dyads (childage= 2-5 years, 85.2% Black) living in poverty and without an individual child bed were randomly assigned (multimethod randomized waitlist control trial design) to BfK intervention ∼1 week postbaseline (initial intervention) or ∼2 weeks postbaseline (waitlist control), with follow-up at 1 month. BfK intervention (home bed delivery and written sleep health education) was provided to all families. Children wore actigraphs and mothers completed daily diaries to assess child and maternal sleep, child behavior, and maternal mood for the initial 1-week comparison period. Maternal-reported child sleep and behavior (internalizing and externalizing problems) were collected at 1 month after BfK participation for all families; 11 families completed a qualitative interview at 1-month follow-up.

RESULTS

At 1 week after BfK, mothers' sleep duration increased by 1 hour compared to that of waitlist controls. No changes were found in child sleep, child behavior, or maternal mood. However, at 1 month after BfK intervention, improvements were found in mother-reported child night awakenings, sleep quality, sleep problems, and behavior. Mothers qualitatively reported significant BfK benefits for child sleep and family well-being, although they noted challenges to transitioning young children to sleeping independently.

CONCLUSIONS

Bed provision and sleep education for families living in poverty has an immediate impact on maternal sleep and reported well-being. Child sleep and behavioral improvements are seen by 1 month, with children experiencing an initial adjustment period to sleeping independently.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Impact of Beds for Kids Program on Child Sleep; URL: https://www.clinicaltrials.gov/ct2/show/NCT03392844; Identifier: NCT03392844.

CITATION

Williamson AA, Min J, Fay K, Cicalese O, Meltzer LJ, Mindell JA. A multimethod evaluation of bed provision and sleep education for young children and their families living in poverty. J Clin Sleep Med. 2023;19(9):1583-1594.

Actigraphy‐measured sleep concordance, night‐wakings, intraindividual sleep variability in parents and their children—Associations with childhood sleep disturbances

The relationship between the sleep of parents and their children has primarily been studied using self-reported measures, but data using objective sleep assessments are limited. In particular, objective assessments of sleep disturbance and night-wakings in parents in relation to their children's night-wakings is underexamined. This pilot study employed actigraphy to determine concordance in sleep-wake patterns between parents and their children, and examine temporal links between their wakings lasting five min or longer. The study also explored individual variability in parents' sleep based on parent-reported sleep disturbances in children. A total of 20 parents and children (aged 2-12 years, no co-sleepers) contributed actigraphy data for the 14-night study, totalling 280 nights of data. Parents reported their sleep quality using the Pittsburgh Sleep Quality Index, and children's sleep using the Children Sleep Habits Questionnaire. Concordance analysis of actigraphy data revealed an average of 70.6% match in sleep/wake state between parents and children. Parents were three times more likely to have an awakening within 10 min of their child waking than vice versa. Parent-reported sleep disturbances in children were associated with poorer actigraphic sleep outcomes for both the parent and child. Parents of poorly sleeping children demonstrated greater variability in their bedtime, and wake after sleep onset. Further examination of temporal links between parent-child sleep can improve our understanding of factors that predispose or precipitate sleep disturbances across families. Given the high concordance in parent-child sleep and poorer actigraphy sleep outcomes in parents of children with sleep disturbances, there is a need to deliver efficacious sleep interventions at the family level.

The physical home environment and sleep: What matters most for sleep in early childhood

The physical home environment is thought to play a crucial role in facilitating healthy sleep in young children. However, relatively little is known about how various features of the physical home environment are associated with sleep in early childhood, and some of the recommendations clinicians make for improving child sleep environments are based on limited research evidence. The present study examined how observer and parent descriptions of the child's physical home environment were associated with child sleep, measured using actigraphy and parent's reports, across a year in early childhood. The study used a machine learning approach (elastic net regression) to specify which aspects of the physical home environment were most important for predicting five aspects of child sleep, sleep duration, sleep variability, sleep timing, sleep activity, and latency to fall asleep. The study included 546 toddlers (265 females) recruited at 30 months of age and reassessed at 36 and 42 months of age. Poorer quality physical home environments were associated with later sleep schedules, more variable sleep schedules, shorter sleep durations, and more parent-reported sleep problems in young children. The most important environmental predictors of sleep were room sharing with an adult, bed sharing, and quality of both the child's sleep space and the wider home environment. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Maternal nighttime sleep and infant-mother attachment security: The mediating role of maternal parenting quality during bedtime and free play

The present study examined mothers' emotional availability (EA) during daytime free play and bedtime as a mediator of linkages between maternal nighttime sleep and infant-mother attachment. Participants included 153 mothers (85% White) with infants (53% female). When infants were 1, 3, 6, 9, and 12 months, maternal sleep was assessed using actigraphy and daily sleep diaries for 7 consecutive days. At each time point, mothers' EA was scored from one observation of daytime free play and from one evening observation of infant bedtime by trained observers who were blind to all other participant information. Average scores were created for maternal sleep and EA across the five occasions in the first year. At 12 and 18 months, infant-mother attachment security in the home was scored by blind observers using the Attachment Q-Set, averaged across the two age points, and used in analyses. Mediational analyses revealed that mothers who experienced highly variable sleep and had poor sleep quality were less emotionally available with infants at bedtime during infants' first year of life, which in turn was predictive of lower infant-mother attachment security in the second year, supporting mediation. Linkages between maternal sleep characteristics and daytime EA were less evident. Later maternal sleep timing was also directly predictive of low attachment security, after accounting for maternal EA. Findings emphasize that poor parental sleep places both parenting and infant socioemotional development at risk, and that parental sleep hygiene and sleep habits should be a salient focus of parenting intervention. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Socioeconomic status and infant nighttime sleep across the second year of life: The moderating role of infant attachment security

This study examined socioeconomic status (SES) and attachment security as predictors of infant nighttime sleep during the second year. Participants included 128 mothers (86% White) with infants (48.4% boys). Data collection took place between April, 2009 and February, 2014. At 12, 18, and 24 months, infant sleep was assessed via actigraphy and daily diaries, and attachment with the Attachment Q-Set. SES indicators included income-to-needs ratios and education. Lower SES predicted greater variability in sleep duration and later sleep timing only for less secure infants. Less secure attachment was associated with poorer sleep at both between- and within-person levels, especially when infants were 12 months of age. Results emphasize the complex interactive effects of environmental and relational factors on infant sleep.

Socioemotional behaviour of toddlers influenced by the sleep patterns: Prevalence study

Background:

This study investigates the influence of sleep duration and sleep patterns on the social-emotional behaviour of 3–70-month-old children.

Methods:

A Brief Infant Sleep Questionnaire (BISQ) and Ages, Stages Questionnaire: Social-Emotional (ASQ:SE) were filled by the participants through a web link. The internal consistency of the items used in the questionnaire was analysed using Cronbach’s alpha and the effects of sleeping disorders on the likelihood of children having social-emotional problems were performed by binary logistic regressions.

Results:

The highest level of bedtime resistance and nocturnal awakening was observed in children of 27–32 months of age, while sleep anxiety was maximum in 42–53-month-old children. The logistic regression models were found to be statistically significant with Χ² (3) =19.556 for 3–8-month-old children, Χ² (3) =11.874 for 9–14-month-old children, Χ² (3) =8.928 for 15–20-month-old children, Χ² (3) =10.061 for 21–26-month-old children and Χ² (3) =38.358 for 54–70-month-old children, P < 0.0005.

Conclusion:

Our findings imply that no statistically significant association was observed between sleep duration and social-emotional problems, however, sleep disorders significantly impacted social-emotional behaviour and also night-waking caused social-emotional behavioural issues in preschoolers.

Characterizing sleep-wake patterns in mothers and children in an agrarian community: results from the Ghana Randomized Air Pollution and Health Study

STUDY OBJECTIVES

Several studies have examined sleep patterns in rural/indigenous communities, however little is known about sleep characteristics in women of reproductive age, and children within these populations. We investigate sleep-wake patterns in mothers and children (ages 3-5 years) leveraging data from the Ghana Randomized Air Pollution and Health Study (GRAPHS).

METHODS

The GRAPHS cohort comprises of rural/agrarian communities in Ghana and collected multiday actigraphy in a subset of women and children to assess objective sleep-wake patterns. Data were scored using the Cole-Kripke and Sadeh algorithms for mothers/children. We report descriptive, baseline characteristics and objective sleep measures, compared by access to electricity/poverty status.

RESULTS

We analyzed data for 58 mothers (mean age 33 ± 6.6) and 64 children (mean age 4 ± 0.4). For mothers, mean bedtime was 9:40 pm ± 56 min, risetime 5:46 am ± 40 min, and total sleep time (TST) was 6.3 h ± 46 min. For children, median bedtime was 8:07 pm (interquartile range [IQR]: 7:50,8:43), risetime 6:09 am (IQR: 5:50,6:37), and mean 24-h TST 10.44 h ± 78 min. Children with access to electricity had a reduced TST compared to those without electricity (p = 0.02). Mean bedtime was later for both mothers (p = 0.05) and children (p = 0.08) classified as poor.

CONCLUSIONS

Mothers in our cohort demonstrated a shorter TST, and earlier bed/risetimes compared to adults in postindustrialized nations. In contrast, children had a higher TST compared to children in postindustrialized nations, also with earlier sleep-onset and offset times. Investigating objective sleep-wake patterns in rural/indigenous communities can highlight important differences in sleep health related to sex, race/ethnicity, and socioeconomic status, and help estimate the impact of industrialization on sleep in developed countries.

A 1-year longitudinal study of the stress, sleep, and parenting of mothers of toddlers

OBJECTIVES

The present study, building on cross-sectional research showing links between mothers' sleep, stress, and parenting, used a longitudinal design to consider (1) the temporal direction of links between mothers' sleep and stress, (2) whether mother sleep deficits predict change in parenting across time, and (3) whether mother sleep deficits mediate the inverse association between stress and positive parenting.

DESIGN

The study used repeated measures of stress, mother sleep, and positive parenting at toddler ages 30, 36, and 42 months.

SETTING

Data were collected at 2 sites, one in the Midwest and one in the East.

PARTICIPANTS

Four hundred thirteen mother-toddler pairs were followed. Mothers were mostly married, college educated, and middle class, but there was also considerable variability between families.

MEASUREMENTS

Stress was measured via parenting hassles, CHAOS, and role overload scales. Mother sleep was measured via actigraphy. Positive parenting was observed during the bedtime routine and rated using the HOME scale and other items.

RESULTS

Mother stress and sleep were inextricably linked across toddlerhood, and worse sleep was predictive of less observed positive parenting, even when controlling for prior levels of stress and parenting.

CONCLUSIONS

Improving mothers' sleep may be important in efforts to improve their parenting.

Sleep and Negative Affect Across Toddlerhood in the Context of Stress

Negative affect is associated with both high stress and poor sleep, but questions remain about the direction of these associations across time and interactions between stress and sleep, especially in early childhood. The present study examined sleep deficits, family stress, and observed negative affect in a sample of toddlers at 30, 36, and 42 months (N = 504). Negative affect was observed during a parent-child free play task. Sleep was measured via actigraphy. Stress was measured using a cumulative risk index of socioeconomic status, single parent status, household chaos, role overload, parenting hassles, social support, and stressful events. Findings showed few associations between sleep and negative affect, except for toddlers experiencing high levels of family stress. Toddlers experiencing both high stress and poor sleep demonstrated the highest levels of negative affect in the lab at 30 months. Adequate sleep may serve as a protective factor for children in high-stress families.

Association of transportation noise with sleep during the first year of life: A longitudinal study

STUDY OBJECTIVES

During infancy, adequate sleep is crucial for physical and neurocognitive development. In adults and children, night-time noise exposure is associated with sleep disturbances. However, whether and to what extent infants' sleep is affected, is unknown. Thus, this study investigated the relationship between nocturnal transportation noise and actimetry-derived habitual sleep behavior across the first year of life.

METHODS

In 144 healthy infants (63 girls), nocturnal (23:00-7:00) transportation noise (i.e., road, railway, and aircraft) was modelled at the infants' individual places of residence. Using actimetry, we recorded movement patterns for 11 days in a longitudinal design at 3, 6, and 12 months of age and derived the recently proposed core sleep composites of night-time sleep duration, activity, and variability. Using linear mixed-effects models, we determined associations between noise exposure and sleep composites. Sex, gestational age, parents' highest educational level, infants' age, and the existence of siblings served as control variables.

RESULTS

In models without interactions, night-time transportation noise was unrelated to sleep composites across the first year of life (p > .16). Exploratory analyses of an interaction between noise and the existence of siblings yielded an association between night-time transportation noise and sleep duration in infants without siblings only (p = .004).

CONCLUSION

In our study, sleep in infants during the first year of life was relatively robust against external perturbation by night-time transportation noise. However, particularly in children without siblings increasing night-time transportation noise reduced sleep duration. This suggests that the habitual noise environment may modulate individual susceptibility to adverse effects of noise on sleep.

From Alpha Diversity to Zzz: Interactions among sleep, the brain, and gut microbiota in the first year of life

Sleep disorders have been linked to alterations of gut microbiota composition in adult humans and animal models, but it is unclear how this link develops. With longitudinal assessments in 162 healthy infants, we present a so far unrecognized sleep-brain-gut interrelationship. First, we report a link between sleep habits and gut microbiota: daytime sleep is associated with bacterial diversity, and nighttime sleep fragmentation and variability link with bacterial maturity and enterotype. Second, we demonstrate a sleep-brain-gut link: bacterial diversity and enterotype are associated with sleep neurophysiology. Third, we show that the sleep-brain-gut link is relevant in development: sleep habits and bacterial markers predict behavioral-developmental outcomes. Our results demonstrate the dynamic interplay between sleep, gut microbiota, and the maturation of brain and behavior during infancy, which aligns with the lately emerging concept of a sleep-brain-gut axis. Importantly, sleep and gut microbiota represent promising health targets since both can be modified non-invasively. As many adult diseases root in early childhood, leveraging protective factors of adequate sleep and age-appropriate gut microbiota in infancy could constitute a health promoting factor across the entire human lifespan.

Presleep Arousal and Sleep in Early Childhood

Research suggests that arousal during the transition to sleep-presleep arousal-is associated with sleep disturbances. Although a robust literature has examined the role of presleep arousal in conferring risk for sleep disturbances in adults, substantially less research has examined the developmental origins of presleep arousal in early childhood. The authors examined presleep arousal using parent report and psychophysiological measures in a sample of preschoolers to explore the association between different measures of presleep arousal, and to examine how nightly presleep arousal is associated with sleep. Participants included 29 children assessed at 54 months of age. Presleep arousal was measured using parent reports of child arousal each night at bedtime and using a wearable device that took minute-by-minute recordings of heart rate, peripheral skin temperature, and electrodermal activity each night during the child's bedtime routine. This yielded a dataset with 4,550 min of ambulatory recordings across an average of 3.52 nights per child (SD = 1.84 nights per child; range = 1-8 nights). Sleep was estimated using actigraphy. Findings demonstrated an association between parent-reported and psychophysiological arousal, including heart rate, peripheral skin temperature, and skin conductance responses during the child's bedtime routine. Both the parent report and psychophysiological measures of presleep arousal showed some associations with poorer sleep, with the most robust associations occurring between presleep arousal and sleep onset latency. Behavioral and biological measures of hyperarousal at bedtime are associated with poorer sleep in young children. Findings provide early evidence of the utility of wearable devices for assessing individual differences in presleep arousal in early childhood.

Sustained attention across toddlerhood: The roles of language and sleep

The present study examined individual differences in the development of sustained attention across toddlerhood, as well as how these individual differences related to the development of language and sleep. Toddlers (N = 314; 54% male) were assessed at 30, 36, and 42 months using multiple measures of attention, a standardized language assessment, and actigraphic measures of sleep. Toddlers were 80% White. Family socioeconomic status (SES) was calculated using the Hollingshead Four Factor Index and ranged from 13 to 66 (M = 47.59, SD = 14.13). Aims were (a) to examine associations between measures of attention across situations, informants, and time; (b) to consider the independent and interactive effects of language and sleep on attention; and (c) to test potential bidirectional associations between sleep and attention. Findings showed attention measures were stable across time but were only weakly linked with each other at 42 months. Attention was consistently linked with language. More variable sleep and longer naps were associated with less growth in sustained attention across time. Nighttime sleep duration interacted with language in that sleep duration was positively associated with attention scores among toddlers with less advanced language, even when SES was controlled. The findings describe an understudied aspect of how sustained attention develops, involving the main effect of consistent sleep schedules and the interaction effect of amount of sleep and child language development. These findings are relevant to understanding early childhood risk for developing attention problems and to exploring a potential prevention target in family sleep practices. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Sleep and self-regulation in early childhood

What is the role of sleep in children's behavioral, emotional, and cognitive regulation? This chapter considers theoretical and conceptual links between sleep and self-regulation, with special attention to sleep and self-regulation in early childhood. We selectively review the growing body of research on associations between sleep and self-regulation, mentioning some methodological issues. We also consider how child characteristics and sociocontextual factors may interact with sleep in the development of self-regulation in early childhood. We provide some relevant empirical examples from our own research.

Identifying Modifiable Factors Linking Parenting and Sleep in Racial/Ethnic Minority Children

BACKGROUND

Young children from racial and ethnic minority backgrounds are at risk for poor sleep, yet few studies have tested behavioral interventions in diverse samples. This study tests factors that could contribute to associations between parenting skills and child sleep to inform interventions for children at risk of poor sleep outcomes. Specifically, we examined household chaos, caregiver sleep knowledge, and caregiver sleep quality as putative mediators that may be relevant to interventions seeking to improve child sleep.

METHODS

Caregivers (M age 31.83 years; 46.2% African American; 52.1% Hispanic/Latinx, 95% female) of 119 1- to 5-year-old children (M age 3.99 years; 43.7% African American; 42.0% Hispanic/Latinx, 14.3% biracial; 51.3% female) completed measures of parenting practices, child and caregiver sleep, household chaos, and sleep knowledge. Indices of pediatric insomnia symptoms (difficulty falling/remaining asleep) and sleep health (sleep duration/hygiene) were constructed based on previous research. Parallel mediation models were conducted using ordinary least squares path analysis.

RESULTS

Lower household chaos significantly attenuated the relationship between positive parenting skills and better child sleep health, suggesting chaos may serve as a potential mediator. There were no significant contributing factors in the pediatric insomnia model. Sleep knowledge was related to sleep health and caregiver sleep quality was related to pediatric insomnia, independent of parenting skills.

CONCLUSION

Interventions to improve sleep in early childhood may be enhanced by targeting parenting skills and household routines to reduce chaos. Future longitudinal research is needed to test household chaos and other potential mediators of child sleep outcomes over time.

Screen use before bedtime: Consequences for nighttime sleep in young children

There is increasing interest in the relation between screen use and sleep problems in early childhood. In a sample of 30-month-old children, this study used observational measures of screen use during the hour or so leading up to bedtime, parent reports of screen use during the child's bedtime routine, and actigraphic measures of toddler sleep to complement parent-reported sleep problems. Whether screen use was observed during the pre-bedtime period or was reported by the parents as part of the nightly bedtime routine, greater screen use in either context was associated with more parent-reported sleep problems. Additionally, more frequent parent-reported screen use during the bedtime routine was also associated with actigraphic measures of later sleep, shorter sleep, and more night-to-night variability in duration and timing of sleep. These associations suggest the negative consequences of screen use for children's sleep extend both to aspects of sleep reported by parents (e.g., bedtime resistance, signaled awakenings) and to aspects measured by actigraphy (e.g., shorter and more variable sleep).

Mothers' sleep deficits and cognitive performance: Moderation by stress and age

There are well-known associations between stress, poor sleep, and cognitive deficits, but little is known about their interactive effects, which the present study explored in a sample of mothers of toddlers. Since certain types of cognitive decline start during the 20s and continue into later ages, we also explored whether mothers’ age interacted with stress and sleep in the prediction of cognitive functioning. We hypothesized that poorer sleep [measured using one week of 24-hour wrist actigraphy data] and having more chronic stressors [e.g., life events, household chaos, work/family role conflict] would be linked with poorer cognitive performance [both executive function and standardized cognitive ability tasks], and that the interactive combination of poorer sleep and more stressors would account for the effect. We also explored whether this process operated differently for younger versus older women. In a socioeconomically and geographically diverse community sample of 227 women with toddler-age children [age, M = 32.73 yrs, SD = 5.15 yrs], poorer cognitive performance was predicted by greater activity during the sleep period, shorter sleep duration, and lower night-to-night consistency in sleep; it was not associated with higher levels of stress. The interactive effects hypothesis was supported for sleep activity [fragmented sleep] and sleep timing [when mothers went to bed]. The combination of more exposure to stressors and frequent night waking was particularly deleterious for older women’s performance. For younger women, going to bed late was associated with poorer performance if they were experiencing high levels of stress; for those experiencing low levels of stress, going to bed late was associated with better performance.

The Validity, Reliability, and Feasibility of Measurement Tools Used to Assess Sleep of Pre-school Aged Children: A Systematic Rapid Review

Background: Sleep of pre-school aged children is important for their health and development, but there are currently no standards for measuring sleep in this age group. We aimed to examine the validity, reliability and feasibility of tools used to assess sleep of pre-school aged children. Methods: Studies were eligible for inclusion if they examined the validity and/or reliability and/or feasibility of a measurement tool used to examine sleep of pre-school aged children (aged 3-7 years). We systematically searched six electronic databases, grey literature and trial registries. We manually searched topic specific journals, reference and citations of included studies, and reference lists of existing reviews. We extracted data and conducted a risk of bias assessment on the included studies using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) risk of bias checklist. We used a narrative synthesis to present the results. Results: Sixteen studies met the inclusion criteria: these explored accelerometers (n = 3) and parental reported tools (n = 13; nine questionnaires, six diaries). Studies assessed construct validity (n = 3), criterion validity (n = 1), convergent validity (n = 13), test-retest reliability (n = 2), internal consistency (n = 4) and feasibility (n = 12). Most studies assessed the convergent validity of questionnaires and diaries compared with accelerometers, but the validity of accelerometers for sleep in this age group is unknown. Of studies with a low risk of bias, one sleep diary was shown to be valid for measuring sleep duration. No measurement tools were appropriate for determining sleep quality. Reporting of reliability and feasibility was minimal. Discussion: The evidence base in this field is limited, and most studies had high risk of bias. Future research on sleep in pre-school aged children should focus on assessing the validity, reliability and feasibility of accelerometers, which in turn will improve the quality of studies that assess questionnaires and diaries against accelerometers. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021230900; PROSPERO: CRD42021230900.

Which are the Central Aspects of Infant Sleep? The Dynamics of Sleep Composites across Infancy

Sleep during infancy is important for the well-being of both infant and parent. Therefore, there is large interest in characterizing infant sleep with reliable tools, for example by combining actigraphy with 24-h-diaries. However, it is critical to select the right variables to characterize sleep. In a longitudinal investigation, we collected sleep data of 152 infants at ages 3, 6, and 12 months. Using principal component analysis, we identified five underlying sleep composites from 48 commonly-used sleep variables: Sleep Night, Sleep Day, Sleep Activity, Sleep Timing, and Sleep Variability. These composites accurately reflect known sleep dynamics throughout infancy as Sleep Day (representing naps), Sleep Activity (representing sleep efficiency and consolidation), and Sleep Variability (representing day-to-day stability) decrease across infancy, while Sleep Night (representing nighttime sleep) slightly increases, and Sleep Timing becomes earlier as one ages. We uncover interesting dynamics between the sleep composites and demonstrate that infant sleep is not only highly variable between infants but also dynamic within infants across time. Interestingly, Sleep Day is associated with behavioral development and therefore a potential marker for maturation. We recommend either the use of sleep composites or the core representative variables within each sleep composite for more reliable research.

Examining Sleep and Mood in Parents of Children with Sleep Disturbances

OBJECTIVE

The current study examined sleep and mood associations in parents of children with sleep disturbances across a sample of typically developing children and children with neurodevelopmental disorders. The mediating effect of children's sleep on the relationship between parents' sleep and mood was also assessed. The study explored differences in parents' sleep based on whether 1) the child had a sleep disturbance, and 2) the child was typically developing or had a neurodevelopmental disorder.

METHODS

A total of 293 parents of children aged 2-12 years completed an online questionnaire. Parental sleep was examined using the Pittsburgh Sleep Quality Index, the Glasgow Sleep Effort Scale and the Pre-sleep Arousal Scale, and mood was assessed using the Profile of Mood States-short form. Measures for children included the Child's Sleep Habits Questionnaire (CSHQ) and the Strengths and Difficulties Questionnaire.

RESULTS

Across the overall sample, children's sleep disturbances were associated with parents' sleep disturbances, accounting for 22% of the change in parental sleep quality. Children's sleep partially mediated parents' sleep and mood. Significant differences were observed for sleep and mood outcomes in parents of children with sleep disturbances (CSHQ scores ≥41). However, no significant differences were reported for children's sleep disturbances and parents' sleep quality based on whether the child was typically developing or had a neurodevelopmental disorder.

CONCLUSION

Parents of children with sleep disturbances experience poor sleep and high pre-sleep arousal, indicative of insomnia. Given that these parents experience cognitive arousal and insomnia, it is recommended that parents' sleep problems are addressed and treated in clinical settings.

Sleep across early childhood: implications for internalizing and externalizing problems, socioemotional skills, and cognitive and academic abilities in preschool

BACKGROUND

Sleep is thought to be important for behavioral and cognitive development. However, much of the prior research on sleep's role in behavioral/cognitive development has relied upon self-report measures and cross-sectional designs.

METHODS

The current study examined how early childhood sleep, measured actigraphically, was developmentally associated with child functioning at 54 months. Emphasis was on functioning at preschool, a crucial setting for the emergence of psychopathology. Participants included 119 children assessed longitudinally at 30, 36, 42, and 54 months. We examined correlations between child sleep and adjustment across three domains: behavioral adjustment (i.e., internalizing and externalizing problems), socioemotional skills, and academic/cognitive abilities. We further probed consistent associations with growth curve modeling.

RESULTS

Internalizing problems were associated with sleep variability, and cognitive and academic abilities were associated with sleep timing. Growth curve analysis suggested that children with more variable sleep at 30 months had higher teacher-reported internalizing problems in preschool and that children with later sleep timing at 30 months had poorer cognitive and academic skills at 54 months. However, changes in sleep from 30 to 54 months were not associated with any of the domains of adjustment.

CONCLUSIONS

Findings indicate that objectively measured sleep variability and late sleep timing in toddlerhood are associated with higher levels of internalizing problems and poorer academic/cognitive abilities in preschool.