Assessing volume of accelerometry data for reliability in preschool children

Purpose: This study examines what volume of accelerometry data (h·d-1) is required to reliably estimate preschool children’s physical activity and whether it is necessary to include weekday and weekend data.

Methods: Accelerometry data from 493 to 799 (depending on wear time) preschool children from the Melbourne-based Healthy Active Preschool Years study were used. The percentage of wear time each child spent in total (light–vigorous) physical activity was the main outcome. Hourly increments of daily data were analyzed. t-tests, controlling for age and clustering by center of recruitment, assessed the differences between weekday and weekend physical activity. Intraclass correlation coefficients estimated reliability for an individual day. Spearman–Brown prophecy formula estimated the number of days required to reach reliability estimates of 0.7, 0.8, and 0.9.

Results: The children spent a significantly greater percentage of time being physically active on weekend compared with weekdays regardless of the minimum number of hours included (t = 12.49–16.76, P < 0.001 for all). The number of days required to reach each of the predetermined reliability estimates increased as the number of hours of data per day decreased. For instance, 2.7–2.8 d of data were required to reach a reliability estimate of 0.7 with 10 or more hours of data per day; 3.3–3.4 d were required to meet the same reliability estimate for days with 7 h of data.

Conclusions: Future studies should ensure they include the minimum amount of data (hours per day and number of days) as identified in this study to meet at least a 0.7 reliability level and should report the level of reliability for their study. In addition to weekdays, at least one weekend day should be included in analyses to reliably estimate physical activity levels for preschool children.

Patterns of physical activity and sedentary behaviour in preschool children

Background
Little is known about patterns of sedentary behavior (SB) and physical activity among preschoolers. Therefore, in this observational study patterns of SB and moderate-to-vigorous physical activity (MVPA) were examined in detail throughout the week in preschool-aged boys and girls.

Methods
A sample of 703 Melbourne preschool children (387 boys; 4.6 ± 0.7 y) were included in data analysis. SB and MVPA data were collected using accelerometry over an eight-day period. Percentage of time per hour in SB and in MVPA between 08:00 h and 20:00 h was calculated. Multi-level logistic regression models were created to examine the hour-by-hour variability in SB and MVPA for boys and girls across weekdays and weekend days. Odds ratios (OR) were calculated to interpret differences in hour-by-hour SB and MVPA levels between boys and girls, and between weekdays and weekend days.

Results
The highest SB levels co-occurred with the lowest MVPA levels from the morning till the early afternoon on weekdays, and during the morning and around midday on weekends. Besides, participation in SB was the lowest and participation in MVPA was the highest from the mid afternoon till the evening on weekdays and weekend days. The variability across the hours in SB and, especially, in MVPA was rather small throughout weekdays and weekends. These patterns were found in both boys and girls. During some hours, girls were found to be more likely than boys to demonstrate higher SB levels (OR from 1.08 to 1.16; all p < 0.05) and lower MVPA levels (OR from 0.75 to 0.88; all p < 0.05), but differences were small. During weekends, hour-by-hour SB levels were more likely to be lower (OR from 0.74 to 0.98; all p < 0.05) and hour-by-hour MVPA levels were more likely to be higher (OR from 1.15 to 1.50; all p < 0.05), than during weekdays, in boys and girls.

Conclusion
Entire weekdays, especially from the morning till the early afternoon, and entire weekend days are opportunities to reduce SB and to promote MVPA in preschool-aged boys and girls. Particularly weekdays hold the greatest promise for improving SB and MVPA. No particular time of the week was found where one sex should be targeted.

Children's physical activity and screen time : qualitative comparison of views of parents of infants and preschool children

Background
While parents are central to the development of behaviours in their young children, little is known about how parents view their role in shaping physical activity and screen time behaviours.

Methods
Using an unstructured focus group design, parental views and practices around children′s physical activity and screen time (television and computer use) were explored with eight groups of new parents (n=61; child age <12 months) and eight groups of parents with preschool-aged (3–5 year old) children (n=36) in Melbourne, Australia.

Results
Parents generally believed children are naturally active, which may preclude their engagement in strategies designed to increase physical activity. While parents across both age groups shared many overarching views concerning parenting for children′s physical activity and screen time behaviours, some strategies and barriers differed depending on the age of the child. While most new parents were optimistic about their ability to positively influence their child′s behaviours, many parents of preschool-aged children seemed more resigned to strategies that worked for them, even when aware such strategies may not be ideal.

Conclusions
Interventions aiming to increase children′s physical activity and decrease screen time may need to tailor strategies to the age group of the child and address parents′ misconceptions and barriers to optimum parenting in these domains.

Effect of a school-based active play intervention on sedentary time and physical activity in preschool children

Early childhood is a critical time for promoting physical activity. Few studies have investigated the effect of interventions in this population. The aim of this study was to investigate the effect of a school-based active play intervention on preschool children’s sedentary time and physical activity. Preschool children were recruited from randomly selected preschools. Schools were randomly assigned to an intervention or comparison group. One teacher per intervention school received training from active play professionals in the delivery of a 6-week active play programme. Comparison schools continued their usual practice. Children wore a uni-axial accelerometer for 7 days at baseline, immediately after and at 6-month post-intervention. No significant intervention effects were observed for sedentary time or physical activity. However, sex and hours spent at school were significant predictors of physical activity. Children who spent fewer hours (half-day children) at school were significantly more active than their full-day counterparts. Physical activity during the intervention classes was high even though neither daily physical activity nor sedentary time changed. Notably children who spent more time at preschool were less active suggesting that preschool was not as conducive to physical activity engagement as other environments.

Mathematical thinking of preschool children in rural and regional Australia : research and practice

At what age do young children begin thinking mathematically? Can young children work on mathematical problems? How do early childhood educators ensure young children feel good about mathematics? Where do early childhood educators learn about suitable mathematics activities?

A good early childhood start in mathematics is critical for later mathematics success. Parents, carers and early childhood educators are teaching mathematics, either consciously or unconsciously, in any social interaction with a child.

Mathematical Thinking of Preschool Children in Rural and Regional Australia is an extension of a conference of Australian and New Zealand researchers that identified a number of important problems related to the mathematical learning of children prior to formal schooling. A project team of 11 researchers from top Australian universities sought to investigate how early childhood education can best have a positive influence on early mathematics learning.

The investigation complements and extends the work of Project Good Start by focusing attention on critical aspects of parents, carers and early childhood educators who care for young children. Early childhood educators from regional and rural New South Wales, Queensland and Victoria were interviewed, following a set of structured questions. The questions focused on: children’s mathematics learning; support for mathematics teaching; use of technology; attitudes to mathematics; and assessment and record keeping.

The researchers also reviewed research focusing on the mathematical capacities and potential foundations for further mathematical development in young children (0–5 years) published in the last decade and produced an annotated bibliography. This should provide a good basis for further research and reading.

Based upon the results of this investigation, the researchers make 11 recommendations for improving the practices of early childhood education centres in relation to young children’s mathematical thinking and development. The implications for policy and decision makers are outlined for teacher education, the provision of resources and further research.

Associations of parental rules and socioeconomic position with preschool children's sedentary behaviour and screen time

There is little current understanding of the influences on sedentary behaviour and screen time in preschool children. This study investigated socioeconomic position (SEP) and parental rules as potential correlates of preschool children's sedentary behaviour and screen time.

A review of preschool children's physical activity and sedentary time using objective measures

Identifying current physical activity levels and sedentary time of preschool children is important for informing government policy and community initiatives. This paper reviewed studies reporting on physical activity and time spent sedentary among preschool-aged children (2-5 years) using objective measures.

Fundamental movement skills in relation to weekday and weekend physical activity in preschool children

To examine associations between fundamental movement skills and weekday and weekend physical activity among preschool children living in deprived communities.

Patterns of objectively measured moderate-to-vigorous physical activity in preschool children

Identifying periods of the day which are susceptible to varying levels of physical activity (PA) may help identify key times to intervene and potentially change preschool children's PA behaviors. This study assessed variability of objectively measured moderate-to-vigorous physical activity (MVPA) during weekdays and weekend days among preschool children.

Child developmental outcomes in preschool children following antidepressant exposure in pregnancy

To examine child developmental outcomes in preschool-aged children exposed to antidepressant medication in pregnancy and compare their outcomes to children not exposed.

Fundamental movement skills of preschool children in Northwest England

This cross-sectional study examined fundamental movement skill competency among deprived preschool children in Northwest England and explored sex differences. A total of 168 preschool children (ages 3-5 yr.) were included in the study. Twelve skills were assessed using the Children's Activity and Movement in Preschool Motor Skills Protocol and video analysis. Sex differences were explored at the subtest, skill, and component levels. Overall competence was found to be low among both sexes, although it was higher for locomotor skills than for object-control skills. Similar patterns were observed at the component level. Boys had significantly better object-control skills than girls, with greater competence observed for the kick and overarm throw, while girls were more competent at the run, hop, and gallop. The findings of low competency suggest that developmentally appropriate interventions should be implemented in preschool settings to promote movement skills, with targeted activities for boys and girls.

Dietary sources and sodium intake in a sample of Australian preschool children

OBJECTIVES: To assess dietary sodium intake and the food sources of sodium in a sample of Australian preschool children. DESIGN: Cross-sectional. SETTING: Mothers were followed up when children were approximately 3.5 years of age after participating in a cluster randomised controlled trial: the Melbourne Infant Feeding Activity and Nutrition Trial Program. PARTICIPANTS: 251 Australian children aged 3.5±0.19 (SD) years. PRIMARY AND SECONDARY OUTCOME MEASURES: The average daily sodium intake was determined using three unscheduled 24 h dietary recalls. The contributions of food groups, core, discretionary and processed foods to daily sodium intake were assessed. RESULTS: The average sodium intake was 1508±495 (SD) mg/day, (salt equivalent 3.9±1.3 (SD) g/day) and 87% of children exceeded the Australian Upper Level of Intake (UL) for sodium of 1000 mg/day (salt equivalent 2.6 g/day). Main food sources of sodium were cereal/cereal products (25%), milk products (19%), meat, poultry/game (17%) and cereal-based products (15%). Core foods contributed 65%, and discretionary foods 35% of total daily sodium intake, and within the total diet, minimally processed, processed, processed culinary ingredient and ultraprocessed foods contributed 16%, 35%, 1% and 48% of sodium, respectively. CONCLUSIONS: Within this sample, most children exceeded the recommended UL for sodium. Core and ultraprocessed foods were key sources of sodium which suggests that reductions in the sodium content of these foods are required to reduce sodium intake in young children. These data also provide further support for public health campaigns that seek to reduce consumption of energy-dense, nutrient-poor foods.

Evaluation of Pupillary Diameter in Preschool Children

Few quantitative data exist on pupil diameter, particularly in children. In this article we describe an analysis of pupil diameter and pupil area in normal preschool children during attentive gaze (AG) and spontaneous gaze (SG) using digital imaging. The pupil diameter and pupil area of 200 preschool children aged 4 to 6 years were evaluated. The images were recorded with a digital camera, transferred to a computer, processed by movie software and submitted to the Invert filter of Adobe Photoshop (R) software. Three consecutive measures of pupil diameter and pupil area were taken for both eyes during AG and SG. Arithmetic means of each parameter were calculated and data were expressed in millimeters. Mean pupil diameter was similar for both eyes, presenting values of 4.9 mm during AG and 4.1 mm during SG. Mean pupil area was also similar for both eyes, presenting values of 15.6 mm(2) and 9.1 mm(2) during AG and SG, respectively. There were no differences between boys and girls. However, 6-year-old children showed lower pupil diameter and area under both evaluation conditions.