A meta-analytic approach to the association between inhibitory control and parent-reported behavioral adjustment in typically-developing children: Differentiating externalizing and internalizing behavior problems

Impairments in inhibitory control (IC) are traditionally seen as a vital aspect in the emergence and course of maladaptive behavior across early childhood. However, it is currently unclear whether this view applies to both the externalizing and internalizing domain of parent-reported behavioral adjustment. Furthermore, past (meta-analytic) developmental research and theory characterizing this association have largely neglected the vast heterogeneity of IC measures and conceptualizations. The present meta-analyses examined the association of IC with parent-reported externalizing (N = 3160, 21 studies) and internalizing (N = 1758, 12 studies) behavior problems, assessed with the Child Behavior Checklist (CBCL), in non-clinical populations of children aged 2-8 years. They further investigated the moderating effects of a priori IC categorization, according to a recently proposed two-factor model of IC ("Strength/Endurance" account, Simpson & Carroll, 2019). In line with previous research in the clinical domain, the current results corroborate the notion of a robust, but small association between IC and externalizing behavior problems (r = -0.11) in early childhood. However, although frequently proposed in the literature, no significant linear association could be identified with internalizing behavior problems. Furthermore, in both meta-analyses, no significant moderating effects of IC categorization could be revealed. These findings enhance our knowledge about the cognitive underpinnings of early-emerging maladaptive behavior, indicating that different subtypes of IC are statistically related with externalizing, but not internalizing behavior problems. Overall, the small association of IC ability with behavior problems in non-clinical populations provokes broader questions about the role of IC in behavioral adjustment.