Probable superiority of behavioral interventions--I: traditional comparative outcome

Several scholars have asserted that the major psychological therapies do not differ from one another in range or in degree of their effectiveness (the equivalence of therapies hypothesis). The studies by Sloane et al. (1975), Smith and Glass (1977) and Luborsky, Singer and Luborsky (1975) are most often referenced in support of this assertion. In this, the first of three articles, it is argued that in fact such evidence supports the probable superiority of behavioral interventions.