Common factors or processes of change in psychotherapy?

Abstract

To better identify and understand the role of common factors in psychotherapy, I argue that we should begin with what therapists actually do in psychotherapy, rather than what they say they do. Further, in contrast to Weinberger's position, I argue that there is not yet any convincing evidence regarding the causal role of any common factors in psychotherapy outcome, although research to determine the possible causal role of these and other potential change factors is sorely needed. Finally, I suggest that common factors are not isolated entities that should be taken out of context, but may more fruitfully be considered as complex, multidimensional and interactive processes that are affected by context and change over time. I believe that an important challenge for future work in common factors is the development of theories of the processes of change that include a variety of factors (common and specific) and their interactions.