Survival curves were used to analyze the relationship between chronicity of depression and hospital course in 48 adolescents with unipolar major depression. The 25 adolescents with chronic depression (defined as a continuous course of depressive illness for 1 year or more) did not differ from those with acute depression in age, gender, or socioeconomic status. Despite similar admission and discharge Children's Depression Rating Scale-Revised scores, adolescents with chronic depression had a significantly slower initial rate of improvement. The study suggests that chronicity of depression has predictive validity with regard to acute hospital course in adolescents.