Children aged 1 month to 9 years cross many development thresholds, making the range of topics for measurement and monitoring very broad, extending from the common diseases of childhood to prevention of injury and promotion of health and well-being. As survival of infants and children under 5 years has improved, our focus has shifted to health promotion and child development activities, and to addressing chronic diseases, injuries and disabilities. More attention has also been directed to the previously neglected older child, aged 5 to 9 years.

The risks of morbidity and mortality are more complex for these children. They can still suffer from common childhood infectious diseases but are also vulnerable to morbidity and mortality from injuries and noncommunicable diseases at a higher rate than younger children. WHO supports indicators for measuring child health and development in ways that allow comparison within and between countries. This work is informed by the Child Health Accountability Tracking Technical Advisory Group (CHAT) which is co-convened by WHO and UNICEF.

Another important aspect of monitoring is tracking child survival and cause of death. We work with the UN Interagency group on Child Mortality Estimation (UN-IGME) to track levels and trends in child mortality and the Maternal and Child Epidemiology Estimation Group (MCEE) to monitor child cause of death across the world. Although child survival has improved remarkably over the past 2 decades, progress has been uneven geographically, with two regions, sub-Saharan Africa and Central/Southern Asia accounting for more than 80% of the 5.3 million under-5 deaths in 2019. 

Our joint work helps to build capacity in countries to monitor their own populations and use this information to implement life-saving policies and practices. Our monitoring shows that pneumonia, diarrhoea and malaria still account for one quarter of all child deaths worldwide. Targeted interventions are needed to address these preventable causes of death and also support well-being for both younger and older children, preparing them for adolescence and adulthood.