Research Review: Language and specific learning disorders in children and their co-occurrence with internalizing and externalizing problems: a systematic review and meta-analysis

Background: Some studies suggest that children with language and learning disorders (LLDs) show more internalizing and externalizing problems than their peers. However, the available evidence remains inconsistent, especially regarding the conditions under which these psychological problems occur.

Methods: We performed a meta-analysis of studies comparing children with LLDs and controls on internalizing (53 independent samples, 135 effect sizes) and externalizing problems (37 independent samples, 61 effect sizes) separately.

Results: Children with LLDs showed higher internalizing (Hedges' g = 0.36) and externalizing problems (Hedges' g = 0.42) than controls did. The group standardized difference in internalizing problems was moderated by the primary disorder, with children with language disorders showing more internalizing problems than those with reading disorders. The severity of the primary disorder, IQ, and age did not moderate Hedge's g between children with LLDs and controls in internalizing and externalizing outcomes. The same pattern was found for gender as a moderator of Hedge's g in internalizing problems, while findings for externalizing problems were inconclusive. The results were consistent when methodological variables were assessed, also for informant, sample size, and geographical area. Clinical samples with LLDs reported higher internalizing problems respect to those with difficulties, but findings on externalizing outcomes were limited. Similarly, results on the presence of additional symptoms in learning and language, self-concept, and socioeconomic status were inconclusive, as few studies reported this information. Results were robust when publication bias, publication year, and study quality were assessed.

Conclusions: There is evidence that children with LLDs report higher internalizing and externalizing problems than controls do. Children with language disorders seemed more vulnerable to report more internalizing problems, and clinical samples reported higher problems than those with difficulties. For clinical practice, assessment and interventions should target socioemotional skills to support the psychological well-being of children with LLDs.