Many children who meet criteria for a particular diagnosis also meet criteria for other diagnoses. To determine whether children who meet criteria for both depressive and conduct disorders differ in important ways from children who meet criteria for only one of these categories of diagnoses, Ezpeleta et al. (2006) identified 382 8- to 17-year-olds attending outpatient psychiatric clinics in Barcelona, Spain, who met DSM-IV criteria for major depressive disorder (MDD), dysthymic disorder (DD), conduct disorder (CD), or oppositional defiant disorder (ODD).
They assessed the children with the Diagnostic Interview for Children and Adolescents (DICA), the Children’s Global Assessment Scale (GAS), the Child and Adolescent Functional Assessment Scale, the Columbia Impairment Scale, and the CBCL. Scores were then compared for children who met criteria only for MDD/DD, only ODD/CD, or both categories of diagnoses. Differences between the prevalence rates for 39 different symptoms in the three groups did not exceed chance expectations for children having only one type of disorder versus children having both types of disorders.
Comparison of 32 DSM symptoms of ADHD, Separation Anxiety Disorder, and Generalized Anxiety Disorder also showed no differences exceeding chance expectations. However, the comorbid group obtained significantly worse scores on measures of impairment. On the CBCL, the comorbid group obtained significantly higher scores than the depressed group on 8 of the 11 problem scales that were analyzed and than the conduct disorder group on 3 of the 11 CBCL problem scales.
Profiles of mean standard scores on the CBCL problem scales showed much higher scores for the comorbid group than for the depressive group on the Social Problems, Thought Problems, Attention Problems, Rule-Breaking, Aggressive Behavior, Externalizing, and Total Problems scales.
The comorbid group’s scores exceeded those of the conduct disorder group’s scores by the greatest amount on the Anxious/Depressed and Internalizing scales. The differences between the comorbid and other groups were negligible in terms of DSM symptom criteria and were minimal in terms of the impairment measures. However, the CBCL profiles revealed numerous large differences between the depressive and comorbid groups.
Reference: Ezpeleta, L., Domench, J.M., & Angold, A. (2006). A comparison of pure and comorbid CD/ODD and Depression. Journal of Child Psychology and Psychiatry, 47, 704-712.