This is a open-label Sequential Multiple Assignment Randomized Trial (SMART) of 16 weeks duration with two levels of randomization, one in each of two 8-week stages. Stage1 is a randomized controlled trial; patients will be randomly assigned to one of the treatments with fluoxetine or combination. Subjects who fail to respond will enter the phase 2 randomization，where patients will be randomly assigned to oral sertraline, votioxetine, duloxetine or adding one of aripiprazole, lithium carbonate, and olanzapine to fluoxetine. The primary outcome for the treatment phase is the treatment remission rate and response rate. Secondary outcomes included: symptom scale; Quality of life; Sleep therapy; Symptoms of anxiety; Rumination and safety assessment.
The aim of this project is to investigate the effectiveness of existing common antidepressants and to provide new evidence for depressed children and adolescents who are not responding to their first treatment.