Study protocol for RUFUS-A randomized mixed methods pilot clinical trial investigating the relevance and feasibility of rumination-focused cognitive behavioral therapy in the treatment of patients with emergent psychosis spectrum disorders.

The study is a mixed-method clinical randomized controlled pilot trial with a target sample of 60 patients, who are randomized to either receive 13 weeks of group RFCBT or 13 weeks of treatment as usual (TAU). All patients are examined at the start of the project and at the 13-week follow-up. We will compare changes in outcomes from baseline to posttreatment between group RFCBT and TAU. In addition, qualitative analyzes are carried out to explore feasibility and acceptability and to uncover the patients' experience of receiving the intervention.