Early childhood inequality in cognition: Decomposing change over time from 2004 to 2014

Despite policy efforts, early childhood inequalities have remained relatively stable in England over recent decades. In this study, we aimed to understand the determinants of early childhood inequality and how these have changed in their composition and impact on early child development, using two nationally representative cohorts of pre-school children collected in 2004 (N = 8,990) and 2014 (N = 3,877). Child development was assessed in both cohorts at age three, using the British Ability Scales – Naming Vocabulary test, and developmental inequality was depicted by concentration indices across quintiles of the English Index of Multiple Deprivation. A between-sample test of the concentration index revealed there was no real change to developmental inequality over time. However, decomposition of the concentration index revealed there were some changes to the determinants of inequality. Most notably, higher rates of maternal education were associated with reduced inequality, while living in the most deprived areas was associated with increased inequality, helping to explain the overall net zero change over time. Other factors, such as attending early childhood education and care by age three, made little contribution to developmental inequality, despite much higher attendance in 2014. This study highlights the complexity of factors contributing to early childhood inequality and includes a discussion on where policy efforts may be useful going forward.