Discussion
major depression, treatment-resistant depression, anxiety, depressed, MDD, depression, chronic depression
REMISSION
This is the first multicentered RCT in China to assess the efficacy of DIT for MDD. As expected, participants randomized to DIT + ADM were less depressed following acute treatment than those who received ADM alone. Remission was achieved in 57.45% of patients and 78.72% patients showed response to the treatment. We used an active control of GST + ADM in this study. GST + ADM also yielded improvement in depression that was superior to ADM, with remission and response rates comparable to that in DIT + ADM.The results of our study are consistent with previous studies of DIT. The acceptability and effectiveness of DIT for depression was reported in an initial pilot study by Lemma and colleagues (Lemma et al., In our study, both DIT and GST combined with ADM yielded improvement in depression that was superior to ADM alone. This result may be explained by the extra benefit of combining psychotherapy and medication. Indeed, the most recent meta-analysis exploring the effects of psychotherapy, pharmacotherapy, and their combination in the treatment of depression confirmed the superiority of combined treatment for major depression, chronic depression, and treatment-resistant depression (Cuijpers et al., In the current study, DIT + ADM was not superior to GST + ADM in reducing symptoms of depression in the acute treatment phase. There are few comparative trials of psychotherapies for depression and existing studies are underpowered and suffer from bias, making it difficult to determine the difference of effects among different types of psychotherapies (Cuijpers, Treatment gains were maintained at follow-up, with depression scores remaining lower for patients who received DIT + ADM DIT is a psychotherapy mainly developed to improve symptoms of depression and anxiety. However, research findings have mainly focused on depression. Our study found that DIT + ADM reduced self-report levels of anxiety relative to ADM during the acute treatment phase, but benefits did not continue beyond the 1-month follow-up. Further research is needed to determine whether DIT is of potential benefit in the treatment of anxiety symptoms.There were several strengths in our study. This is the first RCT study of psychodynamic psychotherapy conducted in China that examined the efficacy of DIT in the treatment of MDD. We used GST to control for the confounding effects of common elements of psychotherapy, making our research conclusions more accurate. We designed a relatively long follow-up period (12-month posttreatment) to explore the stability of acute treatment effects.The study also had several limitations. First, because of the influence of COVID-19, the dropout rate was higher than expected, especially during the posttreatment follow-up phase. This introduced an important bias to the study and limited the reliability of posttreatment follow-up data and conclusions that can be drawn about enduring effects of DIT. Second, we focused on the evaluation of clinical symptoms and did not assess treatment acceptability and patients' social functioning or explore more psychological mechanisms. Third, we did not measure non-specific therapy effects, such as the therapeutic alliance and perception of treatment credibility, as well as the influence of therapist factors (Lewis, Locke, Heritage, & Seddon, 