Analysis of the association between physical health and BMI in single-child and multiple-child families: a study based on the SUREG model and the BMA approach

Being a single child has a significant negative impact on physical test scores and BMI, indicating potential vulnerabilities in their physical health. This discovery is crucial for policymakers and educators, prompting them to provide more opportunities for physical activity and to strengthen the cultivation of healthy eating habits among only children, thereby enhancing their physical health and overall well-being.