A School-based to Prevent Obesity Among Children Aged 4-7 Years: A Feasibility Quasi-Experimental Trial in Karachi, Pakistan
A School-based to Prevent Obesity Among Children Aged 4-7 Years: A Feasibility Quasi-Experimental Trial in Karachi, Pakistan
Obesity is a chronic, complex disease that can harm one's health; obesity is characterized by excessive fat deposits. In 2022, 37 million children under the age of 5 were overweight. Over 390 million children and adolescents aged 5-19 years were overweight in 2022, including 160 million who were living with obesity. Childhood obesity can increase the risk of chronic diseases later in life. According to the World Obesity Federation, 5.4 million Pakistani school-aged children will be obese by 2030, thus identified as a leading public health problem. Obesity is a multifactorial problem, and several stakeholders are responsible. From only 8% in 1990 to 20% in 2022, the prevalence of overweight (including obesity) among children and adolescents aged 5-19 has increased significantly. Similar increases have been seen in boys and girls: in 2022, 21% of boys and 19% of girls were overweight. In addition to genetic factors, there are several environmental factors responsible, such as excessive intake of a caloric-dense diet and lack of physical activity. Thus, early childhood interventions are highly recommended to prevent or minimize the risk of being overweight and obese. To reduce obesity among children, school-based healthy lifestyle interventions are identified as a useful setting, as children from different socioeconomic statuses spend a number of hours at school, have one to two lunches, and have opportunities for sports or physical activity.
In Pakistan, few studies are conducted to assess the risk factors contributing to obesity in early childhood. For instance, the results of the Nutritional Assessment among School-going Children in Lahore, Pakistan (NASCL) study were conducted to assess the lifestyle (diet, physical activity, and its association with the weight status and socio-demographic status of primary school children. Results revealed that 57% of children consumed fast food less than a week, whereas 30% consumed it 1-2 times per week and 13% more than three times a week. Moreover, an inverse relationship was found between physical activity, overweight, and obesity (P = 0.001). Similarly, the School Health Education Program in Pakistan (SHEPP) was recently initiated, targeting children aged 8-11 years enrolled in the schools to promote healthy diet and physical activity among 9-11-year-old children.
Approximately 29.8% of school-age children in Pakistan are estimated to be overweight or obese, making childhood obesity a serious public health concern. Sedentary lifestyles and longer sleep durations relative to children of normal weight are risk factors for obesity in Pakistani school children. The Toybox study is a multidisciplinary, evidence-based intervention initiated to reduce obesity in early childhood. The focus is on promoting a healthy diet, consumption of healthy drinks, and physical activity. This study is already implemented in six European countries, namely Belgium, Bulgaria, Greece, Germany, Poland, and Spain, and involved 266 kindergartens; 8709 children and their caregivers were enrolled. One of the strengths of the Toybox study is room for slight adjustments to adapt to the policies, political structures, economic conditions, and cultural attitudes (towards diet and physical activity) of other countries; thus, the first feasibility study outside Europe is planned in Malaysia, which is a Southeast Asian country. To the best of our knowledge, there are no obesity prevention initiatives targeting children (4-7 years of age); hence, we considered it appropriate to start the Toybox Study in Pakistan, as it could be a useful intervention to alleviate the obesity issue, given the high prevalence of childhood obesity in Pakistan. The proposed project will implement culturally specific health promotion to improve the health and well-being of the Pakistani population. We aim to conduct a project in 2 government and 2 private schools located in the District East of Karachi.
The proposed project will target the following Sustainable Development Goals (SDGs): "Good Health and Well-being" (SDG 3).
Obesity is the main driver for the number of chronic diseases. Thus, prevention of childhood obesity can reduce the burden of chronic diseases like diabetes, hypertension, cardiovascular diseases, and a few cancers later in life and decrease morbidity and mortality, along with improving quality of life by reducing the triple burden of disease. In order to lower early death from NCDs and to promote healthy lives for all children, it is imperative that childhood obesity be addressed. Encouraging healthy behaviors from an early age requires a multi-sectoral, comprehensive approach.
Problem Statement: Childhood obesity is rising in Pakistan, yet interventions especially those involving school communities, parents and teachers are scarce. This study aims to fill that void. Preventing childhood obesity can significantly reduce the risk of developing chronic conditions and NCDs such as diabetes, hypertension, cardiovascular diseases, and certain cancers later in life. Addressing childhood obesity is critical to lowering premature deaths caused by NCDs and promoting healthier lives for all children. This aligns directly with Sustainable Development Goal 3 (SDG 3): "Good Health and Well-being," which emphasizes ensuring healthy lives and promoting well-being for people of all ages.
Research Objectives: The aim of this study is to assess the preliminary effectiveness of implementing a school-based intervention to reduce obesity among children aged 4-6 in Karachi, Pakistan.
Objectives
To develop a culturally specific Toybox study, a school-based intervention for preventing obesity among children aged 4-7 years in Karachi, Pakistan, by evaluating school facilities, policies, and practices related to healthy diet, physical activity, and clean drinking water, and exploring the perceptions, barriers, and training needs of teachers and parents.
To check the socio-demographics, anthropometric measurements and dietary intake of the children (4-7 years) enrolled in government pre-primary schools of Karachi
To determine the effectiveness of a culturally specific Toybox study intervention for a healthy lifestyle (diet, drinks, and physical activity) for selected participants.
Scope of Research:
Research Significance: This study will address and minimize the issue of childhood obesity, as it is a major driver of chronic diseases. Preventing childhood obesity can significantly reduce the risk of developing chronic conditions and NCDs such as diabetes, hypertension, cardiovascular diseases, and certain cancers later in life. Addressing childhood obesity is critical to lowering premature deaths caused by NCDs and promoting healthier lives for all children. This aligns directly with Sustainable Development Goal 3 (SDG 3): "Good Health and Well-being," which emphasizes ensuring healthy lives and promoting well-being for people of all ages. By tackling childhood obesity, this intervention contributes to achieving SDG 3 targets, particularly those focused on reducing premature mortality from NCDs, strengthening the prevention and treatment of health risks, and fostering sustainable health and well-being from an early age.
• Public Health Impact: Addresses the rising concern of childhood obesity in Karachi, a major urban area in Pakistan.
• Culturally Relevant Intervention: Adaptation of Toybox study allows tailored strategies suitable to local customs, resources, and barriers.
• Parental and Teacher Engagement: Enhances sustainability by involving primary influencers of children's daily environment.
This research is relevant in the context of increasing childhood obesity rates globally and locally, contributing valuable evidence to guide effective interventions in school settings with community involvement.
RESEARCH METHODOLOGY
• Design:
o Study Design: Quasi-experimental study, one-group pretest and posttest study design. All the suggested interventions by the original Toy box study (intake of a healthy snack, healthy drinks, increase in physical activity, and reducing screen time) with known efficacy will be included. Thus, it will be unethical to include a control group
Duration of Study: 10 months after ethical approval from the institute. In the first 3 months we will be conducting qualitative interviews and work on development of a culturally specific intervention. In the next 3 months we will be implementing the intervention developed in the school , while the intervention assessment period will extend to four months to accommodate school holidays and examination schedules.
o Study Population: The data will be collected from parents and teachers of children between 4-7 years of age attending Government and private schools of Karachi
o Sample Size: Using PASS version 11, two-sided paired z-test a sample size of 22 achieves power 95% to detect a mean of paired differences of outdoor active play in intervention group was 4.5 [11] with standard deviation of paired differences of 4.54 [11] significance level (alpha) of 0.01. To improve the reliability and validity of our quasi-experimental study, we plan to raise the sample size from 22 to 30 participants. With this modification, we want to increase the statistical power of our findings and more reliable outcomes.
o Sampling Technique: A non-probability, convenience sampling method will be used for both qualitative and quantitative data collection.
Sample Selection: The qualitative and quantitative data will be collected from parents and teachers of children between 4-7 years of age attending government and private schools located in the District East of Karachi, Pakistan. Schools from District East was selected due to accessibility and feasibility of data collection, to allow timely implementation of the study.
• Data Collection Procedure:
o Ethical Consideration: Study protocol was submitted to obtain approval from the Institutional Review Board (IRB) of Dow University of Health Sciences, Karachi, Pakistan (IRB-3847/DUHS/Approval/2025/177). Informed consent will be obtained from all participating parents and teachers before collecting data. Participation will be entirely voluntary, and participants will be informed of their right to withdraw from the study at any stage without any penalty.
All data collected will be kept strictly confidential and will be used for research purposes only and access will be limited to the research team only.
• Study Phases: This study is conducted in four phases. Brief detail on the four phases is given below:
o Phase one (Needs Assessment): An assessment was conducted to evaluate school facilities ( drinking water availability, healthy diet, physical activity opportunities) using an interview administered questionnaire.
Focus group discussions were conducted with parents and teachers to assess their perspectives on the importance of healthy lifestyle in early childhood, barriers in providing healthy diet at school and home and training required to promote healthy behaviors.
Results from FGDs helped modify the Toybox material according to Pakistan's cultural context.
o Phase two (Baseline data collection): Baseline data were collected from teachers and parents to evaluate their knowledge, practices and attitudes regarding promotion of healthy snacking, drinking water, physical activity and screen time
Data included anthropometric measurements, dietary and fluid intake, physical activity and screen time. All variables will be measured before and after the intervention.
o Phase three (Planning Phase): Educational material (posters, booklet, teacher activity guide book, educational videos) were developed in English and then translated to Urdu. The material will be age appropriate and culturally specific to Pakistan's context.
Teachers will be trained to deliver the developed educational material effectively focusing on healthy snacking, water intake, physical activity and screen time.
o Phase four(Implementation Phase): The teachers will conduct interactive sessions using the activity guidebook. Parents will receive educational brochures and short videos on healthy diet, water intake, physical activity and screen time.
The duration of the intervention will be 3 active months. The intervention assessment period will extend to four months to accommodate school holidays and examination schedules.
o Study Instruments:
o Qualitative Data:
Focus group discussions (FGDs): Qualitative data was collected using FGDs with both parents and teachers to assess their knowledge, attitudes and perceptions on child nutrition, physical activity and sedentary activities. A semi structured FGD guide was developed based on study objectives. FGDs were audio recorded, transcribed and translated to English and analyzed using thematic analysis.
o Quantitative Data:
o Audit questionnaire: A questionnaire to evaluate the school's environment.
o Primary care giver questionnaire: A questionnaire was administered to parents to collect information on the family background and lifestyle factors(such as parental education, occupation, child's sleeping patterns), parental and child behaviors including fluid intake, snacking patterns, physical activity and screen time. This questionnaire also includes questions on the child's medical history. The questionnaire was translated to Urdu and back translated to English.
o Teacher's questionnaire: A questionnaire was administered to teachers to collect information on classroom environment and school practices related to snacking, fluid intake, physical activity and screen usage. This questionnaire also assessed teachers knowledge, practice and attitudes related to healthy snacking, fluid intake, PA and sedentary behavior.
Dietary intake: Diet including main meals and snacking patterns was assessed using a validated, modified version of the ToyBox Food Frequency Questionnaire (FFQ) administered by a research assistant. The FFQ was translated in Urdu and back translated to English. A generic food photograph atlas was used to assist participants in estimating portion sizes.
Fluid Intake: Was assessed using a modified version of ToyBox Food frequency questionnaire administered by a research assistant. The FFQ was translated in Urdu and back translated to English. A generic food photograph atlas was used to assist participants in identifying portion sizes.
Inclusion Criteria:
Exclusion Criteria: