This article delves into the methodology and participant demographics of the SUNRISE pilot study, a crucial preliminary investigation documented under study reference 00912 (part of DOI: 10.1186/s40814-021-00912-1). Conducted within the greater Dhaka metropolitan area in Bangladesh, this pilot study laid the groundwork for understanding 24-hour movement behaviors in early childhood. The research meticulously examined various aspects, from recruitment strategies in diverse school settings to the comprehensive assessment of physical activity, sedentary time, sleep patterns, and cognitive and motor skills in preschool-aged children.
Participants and Setting
The SUNRISE pilot study strategically selected three schools within Dhaka to capture a spectrum of environments: Dhaka Premier School and Akij Foundation School, situated in urban locales, and Akij Bonoful Foundation School, representing a more rural-like setting in a less developed area of Dhaka. School principals were engaged and provided permission for the study, ensuring ethical considerations were prioritized from the outset. Parents of children aged 3 to 5 years were then contacted through school teachers, and informational meetings were held at each school to explain the study’s purpose and obtain informed written consent. To manage any potential discomfort in children during the study, each school offered support to accommodate unsettled participants. Ethical approval for the study was granted by the Institutional Review Board of Biomedical Research Foundation, Bangladesh (Memo No: BRF/ERB/2019/03), and the University of Wollongong Human Ethics Research Committee, underscoring the rigorous ethical standards maintained throughout the research process.
Data collection spanned from March to June 2019. Prior to fieldwork, all data collectors underwent extensive training to ensure consistency and accuracy in data acquisition. A single day was dedicated to each participating child, encompassing anthropometric measurements, fine and gross motor skill assessments, executive function evaluations, and the placement of accelerometers. On the same day, parents completed an interviewer-administered questionnaire in the local language, gathering essential demographic information for both parent/caregiver and child, as well as details about the child’s typical movement behaviors. As a follow-up, between May 20 and May 30, 2020, during the COVID-19 pandemic, parents who had participated in the initial SUNRISE pilot study were contacted via telephone. This follow-up aimed to collect data on how children’s movement behaviors were impacted during the pandemic, adding a critical dimension to the study.
Measures and Procedures
The SUNRISE pilot study employed a comprehensive set of measures to thoroughly assess the physical and cognitive development of the participating children.
Anthropometrics
Children’s height and weight were measured with precision. Height was assessed using a portable stadiometer (Leicester 214 Transportable Stadiometer; Seca, Germany), while weight was measured barefoot using a digital scale (SECA 878). To ensure accuracy, all measurements were taken twice, and the average was used for subsequent analysis. Body mass index (BMI) was then calculated, and BMI-for-age (BAZ), height-for-age (HAZ), and weight-for-age (WAZ) z-scores were computed using the WHO AnthroPlus software (version 1.0.4; WHO, Geneva, Switzerland). These scores allowed for the classification of children according to the World Health Organization’s growth reference standards [13, 14].
Accelerometry
To objectively measure physical activity, sedentary time, and sleep patterns, accelerometry was utilized. Two types of accelerometers were employed: the ActiGraph wGT3x-BT, worn on the right hip, and the activPAL 4, attached to the right thigh. These were fitted before other measurements were taken. Children were instructed to wear the accelerometers for a continuous period of 4 days, only removing the ActiGraph for water-based activities like bathing or swimming.
Data from the ActiGraph was processed using ActiLife software (version 6.1.2.1, ActiGraph Corporation). The accelerometers were set to record data at a 30 Hz sampling rate, which was then integrated into 15-second epochs for analysis using a low-frequency filter. For data to be considered valid for analysis, each child needed to have at least 24 hours of data, with a minimum of 6 hours of wear time during waking hours. Valid 24-hour days were identified through visual inspection of ActiGraph data, looking for movement peaks throughout the entire day (midnight to midnight). Days with minimal activity peaks during typical sleeping periods were excluded, as it was assumed the monitor was removed. A pre-determined time filter (7:20 AM to 9:10 PM), based on average parent-reported wake and bedtimes, was applied to valid 24-hour days to isolate waking hours for physical activity (PA) and sedentary behavior (SB) analysis. Periods of 20 or more consecutive minutes of zero counts during waking hours were classified as non-wear time and were excluded [15]. Established cut-points were used to categorize waking wear time into sedentary behavior (SB < 100 counts per minute), light physical activity (LPA; 100–2295 CPM), and moderate-to-vigorous physical activity (MVPA; ≥ 2296 CPM) [16, 17]. Due to skin irritation issues encountered with the activPAL device, the study only assessed and reported on its feasibility, not its data in this particular pilot study.
Sleep, Screen-Time, and Restrained Sitting
Caregivers provided reports on their children’s sleep schedules, including nighttime sleep and naps. Total sleep duration was calculated by summing nighttime sleep duration (bedtime to wake-up time difference) and nap duration. Caregivers also reported on several other aspects of children’s daily routines, including time spent outdoors, screen time and screen use before bedtime, time spent restrained (strapped in and unable to move freely), and general sitting time.
Executive Functions
Executive functions were evaluated using iPad-based games from the Early Years Toolbox (www.eytoolbox.com.au) [18]. These games targeted cognitive flexibility (shifting), inhibitory control, and visual-spatial working memory. The “Card Sort” game, taking about 5 minutes to complete, measured attentional flexibility, with scores ranging from 0 to 12. The “Go/No-Go” game assessed inhibitory control by requiring children to tap a fish but avoid tapping a shark; scores ranged from 0 to 1, with 1 being the highest. The “Mr. Ant” game evaluated working memory by having children recall and tap locations of colored dots on an ant’s body; scores ranged from 0 to 8 per level.
Gross and Fine Motor Skills
The Ages and Stages Questionnaire-3 (48 months, ASQ3) was used to assess gross and fine motor skills [19]. Children were given two attempts for gross motor tasks; performance was categorized as “yes,” “sometimes,” or “not yet.” For fine motor tasks, only one attempt was allowed, with classification as “yes” or “not yet,” scored according to the ASQ-3 tool. For each ASQ task, children were categorized into one of three developmental classifications provided by the ASQ-3 tool, indicating need for follow-up, potential benefit from extra practice, or being on schedule [19].
COVID-19 Questionnaire
A specifically designed COVID-19 questionnaire, comprising 25 questions, was administered to assess changes in children’s physical activity, sedentary behavior, screen time, and sleep patterns during the peak of COVID-19 restrictions in Bangladesh. Questions regarding time spent in movement behaviors and outdoors mirrored those in the initial questionnaire to allow for direct comparison and analysis of behavioral changes due to the pandemic.
Sample Size
The sample size for this pilot study was determined based on the primary aim of assessing the feasibility of recruiting children from both urban and rural settings and evaluating the practicality and acceptability of the proposed data collection methods for the main SUNRISE study. A target sample of 100 children, with 50 from urban and 50 from rural locations, was deemed sufficient to meet these pilot study objectives [11].
Data Analysis
Statistical analyses were conducted using SPSS Statistics for Windows version 26.0 (IBM Corp, Armonk, NY). Descriptive statistics, including means with 95% confidence intervals or frequencies and percentages, were calculated for all study variables. Mann-Whitney U tests were used to compare differences in anthropometric indicators, movement behaviors, motor skills, and executive function between sexes and residential settings. Chi-square or Fisher exact tests were employed to examine differences in the proportion of children meeting 24-hour movement guidelines across sexes. Wilcoxon signed-rank tests were utilized to analyze changes in movement behaviors before and during the COVID-19 period. Statistical significance was predetermined at p < 0.05.
