Determinants of developmental progress in pre-schoolers referred for neuro-developmental diagnosis

Aim: To determine factors associated with change in developmental progress in pre-schoolers referred to a developmental clinic. Methods: Of 360 pre-schoolers referred to a Child Assessment clinic for neuro-developmental diagnosis before 3.6 years, 190 (53%) were reassessed prior to school entry and recruited to this study. They were assessed with the Bayley Scales of Infant and Toddler Development (3rd edn) before 3.5 years and the Griffiths Mental Development Scales before school entry. The influence of medical and environmental variables on improvement or deterioration in scores (±0.5 SD) was examined using logistic regression. Results: Consistent scores were present in 51.6% of children, and associated with environmental variables. Children with stable scores were more likely to live in a suburb of social advantage (OR = 3.2; 95%CI = 1.37–7.64, P = 0.008) or to come from families dependent on welfare or public housing (OR=4.8; 95%CI = 2.19–10.49, P < 0.001). Improvement was seen in 18.1% of children; they were more likely to have commenced therapy after the first assessment (OR = 2.4; 95%CI = 1.05–5.58, P = 0.038). Deterioration of scores was seen in 30% of children. Children with a mild delay on initial assessment were less likely to deteriorate (OR = 2.9; 95%CI = 1.16–7.04, P = 0.022), while lower scores were more likely in children with neuro-motor disabilities (OR = 10.8; 95%CI = 2.64–44.58, P < 0.001), and chromosomal variations of both known and unknown significance (OR = 4.4; 95%CI = 1.54–12.76, P = 0.006). Conclusions: Socio-economic advantage and disadvantage are associated with stable scores, but introducing intervention is associated with improved scores. Deterioration is most likely in children with chromosomal variations or neuro-motor disabilities, and regular reassessment of these children is recommended.