Already in 2008 psychoanalyst Falk Leichsenring, University of Giessen, and behaviour therapist Sven Rabung, University of Hamburg-Eppendorf, demonstrated in a meta-analysis that long-term psychodynamic therapy (LTPP ) is more effective with complex mental disorders than are less intensive therapies. In 2011 they reaffirmed this result in a further meta-analysis. They were also able to show that the patients made further progress after completion of treatment: the extent of its effect further increased after the end of treatment.
In 1999, a study by Perry et al. showed that 50 percent of patients with a personality disorder improve after 1.3 years and 92 sessions. For 75 percent of patients things end up improving after 2.2 years (216 sessions).
Another study – different result
In March 2012, epidemiologist Yolba Smit (Leuth, Netherlands) and colleagues from the University of Maastricht, Amsterdam (Netherlands) and Stanford (USA) then published a study stating that psychodynamic long-term therapy is not more effective than other methods – and that’s only at best. It might even counteract a recovery. Yolba Smit and colleagues analysed 11 randomised or quasi-randomised controlled trials.
Smit et al. examined the extent to which patients after undergoing psychotherapy had recovered at the time of the latest follow-up examination. They found out that the patients did not differ in terms of general psychiatric symptoms, personality pathology and social functioning – regardless of which treatment they had done. While true that psychodynamic long-term therapy fared significantly better when compared with unspecialised psychotherapy, this was not so when psychodynamic long-term therapy was opposed to specialised control treatments.
Falk Leichsenring and colleagues subsequently conducted a further meta-analysis, whereby they included two other large meta-analyses. This study has now been published in the form of a discussion on the study by Smit et al. Leichsenring and colleagues again came to the conclusion that psychodynamic long-term treatment of complex disorders is significantly more effective than less intensive forms of psychotherapy.
What does long-term therapy mean?
In their analysis of the Smit study, Leichsenring et al established: Smit and colleagues had used inconsistent inclusion and exclusion criteria. Leichsenring et al. based their work on a definition of “long-term psychotherapy” using the definition from previous meta-analyses. According to this, a psychodynamic long-term therapy constitutes at least 50 sessions, or a minimum duration of one year. Smit et al. however defined long-term therapy as a treatment involving at least 40 sessions and a minimum of one year. They therefore included a study in which patients completed only 24.9 sessions over a year. Another study which Smit et al. refer to as “LTPP” lasted only 31 sessions.
Furthermore Leichsenring et al. only evaluated studies in which treatment was completed. Smit et al. however included studies in which treatments were in some instances still ongoing. However Smit et al. labelled procedures in some instances as “psychodynamic” which could not be regarded as purely psychodynamic, for intance “Community Treatment by Experts” (CTBE). What’s more Smit et al. worked with one study in which they evaluated “general psychiatric management” as a psychodynamic long-term therapy.
Leichsenring et al. also considered the “sessional ratio” between the two studied groups as important. While the ratio of long-term psychotherapy sessions in their studies compared to the number of sessions with other therapies amounted to 1.96, the “sessional ratio” in the study by Smit et al. was calculated to be just 1.35. That is, the patients in the LTPP groups had not had many more therapy sessions than the patients in the control groups.
Leichsenring and colleagues discuss that “allegiance effect” in the study by Smit et al. could have played a special role. Under “allegiance effect” what is meant is that scientists who believe in their (psychotherapy) method, as a result of their model fidelity and their conviction, retain the results in a study that fit in with their concepts.
Psychodynamic long-term therapy is more effective on complex mental disorders than are less intensive forms of therapy. It’s true that a meta-analysis appeared in 2012 (Smit et al.), which states that psychodynamic long-term treatment provides no substantial advantages. However, Giessen researchers at Giessen working under Falk Leichsenring put this study under the microscope and confirmed earlier results which indicate that psychodynamic long-term therapy is superior to other forms of therapy in dealing with more severe disorders.