Despite growing interest in early childhood development globally, internationally validated tools to assess the development of children under the age of three at population level remain scarce. In the Global Scales for Early Development (GSED) project existing efforts have been brought together to develop a harmonized new methodology to assess development in children up to 36 months through measures that are culturally neutral, easy to administer, open access and acceptable and understandable to caregivers and children. 

The GSED consist of two measures for population and programmatic evaluation: 1) a caregiver-reported Short Form (SF); and 2) a directly administered Long Form (LF). Current evidence indicates that the psychometric properties of the GSED SF and LF are comparable. A combination of GSED SF and LF may be used to increase measurement precision and sensitivity to potential changes following interventions. The GSED also include measures that are being tested (and can be made available on demand): 3) a caregiver-reported Household Form (HF) designed to be integrated into large-scale and national-level surveys for monitoring child development; and 4) a caregiver-reported Psychosocial Form (PF) to measure of children’s psychosocial skills and behaviours. 

The GSED SF, LF and HF are measures on a single underlying scale to produce one overall score of development, the Developmental score (D-score), which is intended to reflect children’s holistic development across multiple domains typically captured in this age group (e.g., cognitive, motor, language, and social-emotional). The GSED PF, designed to measure non-normative developmental patterns such as behavioral or regulatory challenges, is not age-ordinal and therefore uses a different metric.  All GSED scores can only be interpreted at population or group level; they are not intended to be used for screening or diagnosis of individual children.  

Development of the GSED measures requires rigorous field testing to evaluate and establish their functioning. Validation has been completed in three countries (Bangladesh, Pakistan and United Republic of Tanzania) which informed the launch of the GSED package v1.0 (GSED measures and related implementation materials). In the meantime, data was also collected in Côte d’Ivoire and validation is ongoing in three more countries (Brazil, People’s Republic of China, and The Netherlands). The GSED package will be revised after completion of validation in all countries at the end of 2024. 

In parallel, additional research questions are being explored with the aim to: i) determine the predictive validity of the GSED package at 5 years of age; ii) develop global norms and standards for child development under 36 months of age (including adjustments of global norms for moderate to late preterm babies); iii) test the GSED package for identification of children with or at risk for neurodevelopmental impairment; and iv) determine the correlation of GSED measures with biological markers.