Abstract
The aim of this study was to examine the relationship between neurodevelopmental areas and possible difficulties in emotional-behavioural variables, and to determine if sex moderated this relationship. A community sample of 231 boys and girls with typical development and with a mean age of 19.84 months was evaluated, using the Bayley-III and CBCL 1.5-5 scales. The main results confirmed: (1) better linguistic abilities in girls in both language areas (receptive communication and expressive communication), finding more evidence according to the Bayesian analysis in expressive communication; (2) in the emotional-behavioural area girls had higher scores in withdrawal; (3) significant negative correlations of low magnitude were found between the Bayley and CBCL scales, particularly in the areas of language and cognitive and internalising and externalising problems; (4) children with low cognitive abilities and those with poor receptive communication showed more inter and externalising difficulties; (5) no significant predictive value or moderating effect of sex was found, (6) the number of participants who simultaneously manifested significant deficits in both domains (neurodevelopmental and emotional-behavioural) was very reduced. Future research should corroborate these results and the characteristics of the relationship found at these early ages. Detecting the population at risk in the first two years of life would enable the implementation of interventions aimed at improving neurodevelopmental deficits and emotional-behavioural problems. Thus, identification of deficits in one domain should lead to evaluation of the other.