Many studies have shown that cognitive therapy is an effective treatment for depression but it can be hard to tell how much of this is down to the effectiveness of the therapy per se and how much of it is down to the competence of the individual therapist. Researchers from Ohio State University studied videotapes of therapy sessions involving 60 adults with moderate-severe depression and their six therapists. The researchers rated the therapists' skills and the patients completed a questionnaire after each session to measure their depression; the researchers didn't know how the patients were getting on when they assessed the therapists' skills. Patients with high levels of anxiety and early-onset depression benefitted most from the highly-rated therapy sessions. Higher levels of therapist competence were related to more symptom improvement during the first four sessions. After 16 weeks the association between therapists' competence and patients' improvement was still there although it was not quite as strong.
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