'You should always look at the washing machine without actually being in it!' Thematic framework analysis of patients' understanding of transdiagnostic cognitive behaviour therapy and its mechanisms.

Findings The analysis revealed four overarching themes and 18 subthemes, four of which corresponded to the difference between the two groups of participants based on treatment efficacy. The four differentiating subthemes were cognitive flexibility and comparison with others, which characterized the group doing well, and cognitive inflexibility and negative attitude towards treatment, which characterized the group doing less well. The theme evaluated as the most important for the efficacy of the transdiagnostic cognitive behaviour therapy and patients' understanding of the treatment was cognitive flexibility, which characterized the group doing well. Limitations Use of qualitative methodology restricts the generalizability of our results. Data are built on answers from only 24 participants.