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The dynamics of internalizing and externalizing comorbidity across the early school years

Published online by Cambridge University Press:  14 October 2016

Cynthia J. Willner*
Affiliation:
Pennsylvania State University
Lisa M. Gatzke-Kopp
Affiliation:
Pennsylvania State University
Bethany C. Bray
Affiliation:
Pennsylvania State University
*
Address correspondence and reprint requests to: Cynthia J. Willner, Yale Child Study Center, Yale University School of Medicine, 230 South Frontage Road, NIHB G03, New Haven, CT 06520; E-mail: cynthia.willner@yale.edu.

Abstract

High rates of comorbidity are observed between internalizing and externalizing problems, yet the developmental dynamics of comorbid symptom presentations are not yet well understood. This study explored the developmental course of latent profiles of internalizing and externalizing symptoms across kindergarten, first grade, and second grade. The sample consisted of 336 children from an urban, low-income community, selected based on relatively high (61%) or low (39%) aggressive/oppositional behavior problems at school entry (64% male; 70% African American, 20% Hispanic). Teachers reported on children's symptoms in each year. An exploratory latent profile analysis of children's scores on aggression/oppositionality, hyperactivity/inattention, anxiety, and social withdrawal symptom factors revealed four latent symptom profiles: comorbid (48% of the sample in each year), internalizing (19%–23%), externalizing (21%–22%), and well-adjusted (7%–11%). The developmental course of these symptom profiles was examined using a latent transition analysis, which revealed remarkably high continuity in the comorbid symptom profile (89% from one year to the next) and moderately high continuity in both the internalizing and externalizing profiles (80% and 71%, respectively). Internalizing children had a 20% probability of remitting to the well-adjusted profile by the following year, whereas externalizing children had a 25% probability of transitioning to the comorbid profile. These results are consistent with the hypothesis that a common vulnerability factor contributes to developmentally stable internalizing–externalizing comorbidity, while also suggesting that some children with externalizing symptoms are at risk for subsequently accumulating internalizing symptoms.

Type
Special Issue Articles
Copyright
Copyright © Cambridge University Press 2016 

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