Emotional-Behavioural Development in Children with Below Average Cognitive Ability

Abstract

Background: Children with below average cognitive ability represent a substantial yet under-researched population for whom cognitive and social demands, which increase in complexity year by year, may pose significant challenges. This study examines the longitudinal relationship between cognitive ability and emotional-behavioural development between age 3-9 years. Methods: Participants consist of 7,134 children from the Growing Up in Ireland study. Cognitive ability was measured at age 3 using the Picture Similarities Scale. A t-score 1-2 standard deviations below the mean was defined as below average cognitive ability (n=767), and scores above this as average/above (n=6418). Emotional-behavioural difficulties (EBDs) were measured using the Strengths and Difficulties Questionnaire (SDQ) at age 3,5 and 9 years. Generalised linear mixed models were used to examine the predictive significance of cognitive ability for longitudinal SDQ scores and change in SDQ score during childhood. The independent association between cognitive ability and clinically significant EBDs was examined using logistic regression. Findings: Cognitive ability was an independent predictor of longitudinal SDQ scores and of change in SDQ score during childhood. Between age 5-9 years, those with below average cognitive ability experienced a significant increase of 0·56 points in SDQ score (95% CI 0·10 – 1·01), whereas those with average/above ability had relatively unchanged scores. After adjustment, children with below average cognitive ability were 1.31 times (AOR 1.31, 95% CI 1.05-1.62, p=0.014), and 1.33 times (AOR 1.33, 95% CI 1.04-1.67, p=0.019) more likely to experience a clinically significant EBD at age 5 and 9 years respectively. Interpretation: Children with below average cognitive ability are at higher risk of EBDs in childhood. A scalable method of early identification should be a research priority for public health, enabling early intervention for cognitive and adaptive outcomes. Funding Statement: This work was performed within the Irish Clinical Academic Training (ICAT) Programme, supported by the Wellcome Trust and the Health Research Board (Grant Number 203930/B/16/Z), the Health Service Executive, National Doctors Training and Planning and the Health and Social Care, Research and Development Division, Northern Ireland. Declaration of Interests: The authors have no conflicts of interest to declare. Ethics Approval Statement: Ethical approval for the GUI study was obtained from the Research Ethics Committee, Department of Children and Youth Affairs Ireland. Written consent was collected from parents/guardians prior to data collection. Secondary analysis of the Anonymised Microdata Files of the GUI study does not require additional ethical approval.