7.1 Estimating SDG 4.2.1 indicator from existing data
The UN Sustainable Development Goals form a universal call to action to end poverty, protect the planet and improve the lives and prospects of everyone, everywhere. All UN Member States adopted the 17 Goals in 2015. The SDG 4 target to ensure inclusive and equitable quality education and promote lifelong learning opportunities for all. SDG 4.2 reads as:
By 2030, ensure that all girls and boys have access to quality early childhood development, care and preprimary education so that they are ready for primary education.
To measure progress, the UN defined indicator 4.2.1 as follows:
Proportion of children under 5 years of age who are developmentally on track in health, learning and psychosocial well-being, by sex.
On July 22, 2020, the indicator was changed into
Proportion of children aged 24-59 months who are developmentally on track in health, learning and psychosocial well-being, by sex.
The exclusion of children 0-24 months is at variance with the importance of healthy growth and development during the first 1000 days of life. Indeed, the UN restricted the age range for practical concerns. Loizillon et al. (2017) report:
The initial recommendation was for the ECDI to measure child development from birth–5 years, but the range was restricted to 3–5 years due to time and resource constraints and limited availability of comparable measurement tools for children under age 3.
The careful scientific approach underlying the D-score fills the gap for children aged 0-24 months. Also, the D-score methodology enables extensions to ages beyond 24 months, permits back-calculation of D-scores from existing data, and acts as a linking pin to compare child development from birth onwards.
The cohorts included in the GCDG study represent a wide range of countries and instruments (see Section 2.1). Combining existing data from such a wide range of countries to create the D-score, is undoubtedly challenging, but doable. Although, in all fairness, we note that obtaining accurate comparisons between world-wide populations requires additional representative (existing) data beyond what is available here.