Abstract
There is growing evidence from RCTs supporting the efficacy of both short-term (STPP) and long-term psychodynamic psychotherapy (LTPP) for specific mental disorders. In a first series of meta-analyses, LTPP was shown to be superior to shorter forms of psychotherapy, especially in complex mental disorders. However, the evidence for LTPP has not gone unchallenged. After several responses have addressed the raised concerns, a recent meta-analysis by Smit and colleagues (2012) again challenges the efficacy of LTPP.
From a methodological perspective, a critical analysis of the Smit et al. meta-analysis was performed. Furthermore, we conducted two new metaanalyses adding studies not included in previous meta-analyses. The purpose was to examine whether the results of the previous meta-analyses are stable.
Due to differing inclusion criteria, the meta-analysis by Smit et al. actually compared LTPP to other forms of long-term psychotherapy. Thus, they essentially showed that LTPP was as efficacious as other forms of long-term therapy. For this reason the meta-analysis by Smit et al. does not question the results of previous meta-analyses showing that LTPP is superior to shorter forms of psychotherapy. In addition, the Smit et al. meta-analysis was shown to suffer from several methodological shortcomings. The new meta-analyses we performed did not find significant deviations from previous results. In complex mental disorders LTPP proved to be significantly superior to shorter forms of therapy corroborating results of previous meta-analyses.
Data on dose-effect relations suggest that for many patients with complex mental disorders, including chronic mental disorders and personality disorders, short-term psychotherapy is not sufficient. For these patients, long-term treatments may be indicated. The meta-analyses presented here provide further support for LTPP in these populations. Nevertheless, there is a need for more research in LTPP and other long-term psychotherapies.