Cognitive and socioeconomic predictors of Stroop performance in children and developmental patterns according to socioeconomic status and ADHD subtype

Abstract

Objectives: We conducted three empirical studies with the aim at (a) examining the cognitive predictors (i.e., working memory, inhibition, cognitive flexibility, reading, and intelligence) of each Stroop Color and Word Test (SCWT) condition (i.e., Word, Color, and Color–Word) and the convergent and divergent validity among measures, (b) examining the socioeconomic predictors of SCWT performance, further establishing normative values according to socioeconomic status (SES) and age, and (c) analyzing the distinctive patterns of performance according to SES and Attention Deficit and Hyperactivity Disorder (ADHD) subtype. Methods: A large sample of typically developing (TD) children from Middle- (n = 779) and Low- (n = 129) SES and ADHD children (n = 44), inattentive versus combined subtype, was evaluated. Multivariate analysis of variances (MANOVAs), Pearson’s correlations, and hierarchical and stepwise regressions analyses were performed. Results: Study 1 results indicated that SCWT conditions are selectively associated with reading speed and executive functions (EFs), and that the former would not depend on child’s IQ. Study 2 findings revealed distinct patterns of SCWTperformance according to SES andselective associations between socioeconomic indicators and SCWT conditions, being maternal education and housing conditions the main predictors. Finally, Study 3 results revealed distinctive patterns of SCWT performance according to ADHD subtype, with no differences on the interference measure amonggroups. Conclusions: Our findings support the validity of the SCWT as a measure of inhibition in TD children. However, when the pattern of SCWT performance is different from the typical expected one (i.e., Word score higher than Color score and this, in turn, higher than Color–Word score), the interference measure should be interpreted with caution but without disregarding the relevant and distinctive information provided by each SCWT condition.