Cognitive development is defined as the growth and change in a person's ability to perform mental tasks, including thinking , comprehension, and reasoning (California Department of Education, 2014). Cognitive development is a process involving a complex interaction between biological and environmental factors (Feinstein, 2003, cited in Wong and Edwards, 2013). Multiple factors arise in early childhood, including breastfeeding, parental intelligence, and obstetric complications, which have been studied to understand their effects on children's cognitive development through adolescence and adulthood. However, research regarding these variables has encountered several limitations. It will be argued that the quality and quantity of formal child care is a key variable that will affect a child's level of cognitive development. The ABS, 2011, defines formal childcare as regulated childcare separate from the child's home, including family care and before and after school care. The importance of the quality of formal child care for cognitive development is highlighted by Albers, Riksen-Walraven and de Worth (2010). They investigated the relationship between the independent variable of caregiver behavior and the level of cognitive development during the first year of life.Albers et al. selected a random sample of seventy daycares of which 86% agreed to participate. Disagreeing daycares gave reasons such as there were no new infants or issues related to organizational situations. 113 parents of children in these daycare centers were invited to participate and 64 gave their consent, the average age of these children being 3.3 years (SD=0.64).The quality of childcare in these nurseries was...... middle of paper .... ../cks/140Scott, J., McNeill, Y., Cavanagh, J., Cannon, M., & Murray, R. (2006). Exposure to obstetric complications and subsequent development of bipolar disorder. The British Journal of Psychiatry, 189, 3-11. doi: 10.1192/bjp.bp.105.010579Socioeconomic status. Retrieved from Australian Bureau of Statistics website: http://www.abs.gov.au/ausstats/[email protected]/Lookup/4250.0.55.001Main+Features32009Sussman, JE, McIntosh, AM, Lawrie, ME and Johnstone, EC (2009). Obstetric complications and mild to moderate intellectual disability. The British Journal of Psychiatry, 194, 224-228. doi:10.1192/bjp.bp.106.033134Wong, HS and Edwards, P. (2013).Nature or nurture: a systematic examination of the effect of socioeconomic status on the developmental and cognitive outcomes of children born prematurely. Maternal and child health J, 17, 1689-1700. doi:10.1007/s10995-012-1183-8