Children’s development in the early years has been shown to be related to their success in later life in a range of areas including education, employment and crime. Determining why some children do better than others in the early years is a key issue for policy and is crucial in attempts to reduce inequalities. This research examines differences in early child development by examining the factors associated with the cognitive ability of children up to age 5 using cognitive assessments administered as part of the Millennium Cohort Study (MCS) and teacher reports of child ability. The results show that younger children, those with low birth weight, lower parental education, lower income and living in social housing is related both to lower achievement, on average. and the probability of being at the bottom of the distribution of cognitive scores at age 5
