Psychiatric disorders with onset in the preschool years: I. Stability of diagnoses.

Objective: To examine the stability of psychiatric disorders with onset in preschool years.
Method: Five hundred ten children aged 2 through 5 years enrolled initially, with 344 participating in a third wave of data collection 42 through 48 months later. The test batteries used for diagnoses varied by child's age, but they included the Child Behavior Checklist, developmental evaluation, Rochester Adaptive Behavior Inventory and a play session (under age 7 years), and a structured interview (Diagnostic Interview for Children and Adolescents, for parent and child) (ages 7 and older). Consensus DSM-III-R diagnoses were assigned using best-estimate procedures.
Results: Intraclass correlations were 0.497 for emotional disorders, 0.718 for disruptive disorders, 0.457 for other diagnoses, and 0.544 for disruptive disorders comorbid with another disorder, indicating moderate stability for all groups of disorders. More than 50% of the children who were aged 2 through 3 years at wave 1 continued to have some psychiatric disorder at wave 2 or 3. Rates were higher for children aged 4 through 5 initially; approximately two thirds were cases subsequently. Odds ratios indicate that having an emotional or disruptive disorder is a strong risk factor for later diagnoses.
Conclusions: While some preschool children in primary care "grow out of" their disorder, an equally large number do not; this finding supports the need for early detection and intervention.