Effectiveness of Day Treatment Group Schema Therapy for Personality Disorders: A Multiple Baseline Single-Case Study.

This is the first empirical study that demonstrated the effectiveness of day treatment GST in patients with severe PDs. Day treatment GST can serve as a stepped care treatment option for nonresponsive patients in outpatient programmes. Further randomized controlled (cost-)effectiveness research is necessary to substantiate these findings and investigate the specific patient populations for which day treatment is essential.