Research review: A meta-analysis of the international prevalence and comorbidity of mental disorders in children between 1 and 7 years.

BACKGROUND

Children younger than 7 years can develop mental disorders that might manifest differently than in older children or adolescents. However, little is known about the prevalence of mental disorders at this early age.

METHODS

We systematically searched the literature in the databases Web of Science, PsycINFO, PSYNDEX, MEDLINE, and Embase to identify epidemiological studies of community samples published between 2006 and 2020. A series of meta-analyses was conducted to estimate the pooled worldwide prevalence of mental disorders in general, specific mental disorders, and comorbidity in young children.

RESULTS

A total of ten epidemiological studies reporting data on N = 18,282 children (12-83 months old) from eight countries met the inclusion criteria. The pooled prevalence of mental disorders in general was 20.1%, 95% CI [15.7, 25.4]. Most common disorders were oppositional defiant disorder (4.9%, 95% CI [2.5, 9.5]) and attention-deficit hyperactivity disorder (4.3%, 95% CI [2.5, 7.2]). The prevalence of any anxiety disorders was 8.5%, 95% CI [5.2, 13.5], and of any depressive disorders was 1.1%, 95% CI [0.8, 1.6]. Comorbidity was estimated at 6.4%, 95% CI [1.3, 54.0].

CONCLUSIONS

The literature search reveals that the epidemiology of mental disorders in children younger than 7 years is still a neglected area of research. The findings also indicate that there are a significant number of young children suffering from mental disorders who need appropriate age-adapted treatment.