What Is the Evidence for Evidence-Based Treatments? A Hard Look at Our Soft Underbelly

In the rising quest for evidence-based interventions, recent research often does not give adequate attention to “nonspecific therapeutic factors,” including the effects of attention, positive regard, and therapeutic alliance, as well as the effects of treatment dose, intensity and actual processes mediating therapeutic change. To determine the extent to which recent clinical trial designs fully this problem, the authors conducted a systematic review of PsychLit/Medline of all controlled child psychotherapy treatment studies from 1995 to 2004. A total of 52 studies were identified that met review criteria: two or more therapy conditions and random assignment of participants to intervention groups. Of the 52 studies, one group (n = 29) compared a presumably active treatment with 1 or more similarly intensive treatments (often an attention control group) presumably not containing the active therapeutic ingredients. Of these, 14 studies found evidence of consistent differences between the two groups, whereas 15 did not. An additional group of studies (n = 27) compared therapy groups with different levels of intensity and “dose” of the putatively active treatment; 13 of these found evidence of the effects of different levels of treatment dose/intensity on outcomes and 14 did not. Four studies met criteria for inclusion in both groups. Across both groups of studies, when positive effects were found, few studies systematically explored whether the presumed active therapeutic ingredients actually accounted for the degree of change, nor did they often address plausible alternative explanations, such as nonspecific therapeutic factors of positive expectancies, therapeutic alliance, or attention. Findings suggest that many child psychotherapy treatment studies have not inadequately controlled for nonspecific factors such as attention and treatment intensity and have failed to assess specific mediators of change. Specific recommendations for future studies are offered, specifically: