Foundations for health and well-being are established early in life, however, evaluation of progress in young child development and effectiveness of strategies to promote development is impeded by the lack of population-based indicators for children under aged 3 years. With the support of the Bernard van Leer foundation the Global Child Development Group (GCDG) held a meeting in April 2014 to bring together researchers and technical experts to agree on a process to identify indicators that could be used within and across populations. The meeting was attended by investigators with existing cohorts from low and middle income countries with developmental data prior to age 3 years as well as follow-up outcome data. The members agreed to pool their data and on a process to derive global population based indicators for child development using innovative data analysis techniques.
The team has now obtained funding from the Bill and Melinda Gates Foundation to conduct this project with the first phase of analyses to be completed by early 2017.
We will apply quantitative methods to inform the development of a scale and indicators of early child development. These analyse build on a process of establishing “growth charts” of early child development, developed by project co-investigator Professor Stef van Buuren. Through a two-stage estimation procedure, based on the Rasch model and the calculation of change scores, van Buuren has shown that data from standardized measures of early child development in the Netherlands form a continuous latent variable (D-score) that has interval scale properties. In this project we will replicate the estimation procedure across 13 cohorts from 10 countries (Bangladesh, Brazil, Chile, Colombia, China, Ecuador, Ethiopia, Jamaica, Madagascar, South Africa) to identify items to include in the D-score, such that the scale’s measurement properties are maintained across the cohorts. Following this we will examine the ability of the score to predict later outcome and document a process to construct age-conditional reference charts. Our goal is to create and evaluate a trajectory of D-scores that can be used on a global scale to calculate differences within and across ages and countries, much as height-for-age growth charts are used to indicate rates of stunting.