Background
Early childhood development (ECD) strongly influences children's basic learning, school success, economic participation, social citizenry and health.Although some risk factors related to childhood development are documented, further exploration is necessary considering various socio-demographic, nutritional, and psychosocial factors.This study aims to examine factors affecting ECD in Vietnamese preschoolers.

Methods
We used data from the representative, cross-sectional round of theVietnam Multiple Indicator Clusters Survey 2011. Early Childhood Development Index questionnaires were administered to mothers of all children aged 36–59 months in the households (N?=?1459). Descriptive statistics and multivariate logistic regression were employed in the analysis.

Results
In Vietnam, 17.2% of children did not reach their full developmental potential within the first 5?years. Children who had childhood breastfeeding (AOR 2.78, 95% CI 1.28-6.02), pre-school attendance (AOR 1.75, 95% CI 1.28-2.39), major ethnicity (AOR 2.41, 95% CI 1.55-3.74), mother with secondary or higher education (AOR 1.69, 95% CI 1.19-2.38) and had relatives who engaged in four or more activities that promote learning (AOR 1.55, 95% CI 1.13-2.14) were more likely to have normal developmental trajectory. Furthermore, children who experienced physical punishment and stunting were 0.69 times (95% CI 0.51-0.95) and 0.71 times (95% CI 0.51-0.98) less likely to be on track for ECD, respectively.

Conclusions
The risk factors associated with delayed ECD were the low level of maternal education, the family's ethnicity, the lack of pre-school attendance, the children's relative not being engaged in learning, the children's experiencing physical punishment, not being breastfed and stunting. This article is protected by copyright. All rights reserved.