Scott Carollo, MFT
Here is an excellent paper from the Feb-March 2010 edition of American Psychologist written by Jonathan Shedler from University of Colorado Denver School of Medicine. He is an experienced research methodologist and psychometrician. He does a great job of bringing together the available research concerning the efficacy of psychodynamic psychotherapy.
For those of us not trained as research scientists the complexities of what constitute a "good" study, let alone the sheer volume of factors involved in meta-analyses, often leave one squarely in anecdotal purgatory. As a research focussed paper it may be of limited interest to some. Still, Shedler's cogent analysis of the data may be of interest to those considering therapy, in therapy or simply interested in therapy generally - not just clinicians and researchers.
Shedler details research which found seven features which reliably distinguished psychodynamic therapy from other therapies. This was determined by empirical examination of actual session recordings and transcripts. This deliniation helps to clarify the aims and focus of psychodynamic therapy and to differentiate these aims from other therapies. Morever, they help Shedler to make the case, in drawing from the research, that some or all of the efficacy of other "evidence-based" therapies, the "active ingredient", may in actuality be inadvertent or unintended psychodynamic elements.
Shedler also makes an interesting point regarding some research findings which suggest that all therapies are equally effective. He believes this might pertain to the fact that symptom-oriented outcome studies are not necessarily designed to recognize some of the primary defining characteristics of psychological health which are the aim and result of psychodynamic work, such as "the positive presence of inner capacities and resources that allow people to live life with a greater sense of freedom and possibility."
Though this is not exactly new, especially to psychodynamically-oriented clinicians, the research presented in the paper shows psychodynamic therapy to unquestionably qualify as "evidence-based". Moreover, the research quite strongly suggests that psychodynamic therapy has lasting effects which can strengthen over time.
I have experienced this both in and out of my chair as a therapist, but/and I appreciate the opportunity afforded by the fruits of researchers' labors to view the process from the angle and understanding which science can provide.