Common factors are not so common and specific factors are not so specified: toward an inclusive integration of psychotherapy research.

The dichotomy between what has been termed empirically supported treatments (EST) and common factors (CF) is false and counterproductive. Neither has a monopoly on empirical truth. The term nonspecific is unproductive and misleading. Specified versus nonspecified is more empirically correct. Assumptions of the EST and CF approaches are questionable. Common factors (both currently specified and not so specified) are reviewed. These include the therapeutic relationship, expectancies, attributions for therapeutic success, exposure, and mastery. Far from maximizing therapeutic success, the CF EST dichotomy and its resulting theoretical squabbles result in weaker outcomes than would be the case if empirical results were taken seriously, and factors shown to be effective (both specified and nonspecified) were systematically investigated and integrated so as to create maximally effective treatments.