Prediction from early development to later achievement has the potential to improve clinical and educational service delivery as well as to inform developmental theory. In this longitudinal study, we asked how well can educational achievement measured in the final year (Grade 9, age 15) of compulsory education--both overall and for outcomes in the…

In many low- and middle-income countries, young children learn a mother tongue or indigenous language at home before entering the formal education system where they will need to understand and speak a country's official language(s). Thus, assessments of children before school age, conducted in a nation's official language, may not fully reflect a…