Patterns of internalizing symptoms and disability functioning in children and adolescents.

Despite findings from previous studies, there is still little consistent knowledge regarding the co-occurrence patterns of somatic, depressive and anxiety symptoms in childhood and adolescence. Moreover, functional disability due to somatic symptoms at different concomitant levels of depression and anxiety is understudied. The present study examined the co-occurrence patterns of somatic symptoms and symptoms of depression and anxiety, in children and adolescents using two-step cluster analysis. Differences in functional disability due to somatic symptoms were tested with ANCOVA controlling for gender and age. The sample comprised 1127 Italian children and adolescents (48.7% males, n = 549) aged 8-16 years (Mage = 11.7, SD = 2.37). Data were collected using the Children Somatization Inventory-24, the Children Depression Inventory, the Screen for Child Anxiety Related Emotional Disorders, and the Functional Disability Inventory. A four-cluster solution based on the co-occurrence of internalizing symptoms best fit the data. The four clusters were labelled as follows: cluster 1: "High somatic symptoms and average depression/anxiety"; cluster 2: "High somatic symptoms and high depression/anxiety"; cluster 3: "Average somatic symptoms and above average depression/anxiety"; and cluster 4: "Low somatic symptoms and low depression/anxiety". Significant differences between the four groups according to gender and age were shown. Participants with high levels of somatic, depressive, and anxiety symptoms reported greater functional disability due to somatic symptoms than the other three groups. Our findings indicate that children and adolescents who demonstrate high symptoms of depression and anxiety also reported higher levels of disability in daily life due to somatic symptoms.