Correspondence to

Background Few studies have examined the relationship between sociodemographic factors and a population-based measure of developmental delay in US children. We identify sociodemographic factors associated with unlikely, probable and possible developmental delay in preschool US children using nationally representative data. Methods All children aged 18 months to 5 years in the 2007 National Survey of Children’s Health were categorised into three groups based on the likelihood of developmental delay (unlikely delay, possible delay and probable delay) using a modified survey version of the Parents ’ Evaluation of Developmental Status questionnaire. Bivariate and multivariate multinomia