American Psychological Association
Psychotherapy: Theory, Research, Practice, Training
Forms of psychotherapy treatment are not neatly separable from one another in actual practice. They differ behaviorally in what they emphasize, but nevertheless they overlap and so cannot be unambiguously compared for effectiveness. Furthermore, forms of psychotherapy are not separable in practice from the therapists who apply them, so apparent differences in effectiveness between forms of treatment are always confounded by differences in effectiveness between therapists. Therapists, however, are separable from one another, and it is therapists not treatment forms that actually treat patients. Therefore, what should primarily be given preference in practice is not treatments empirically certified on the basis of their results in randomized clinical trials but psychotherapists empirically certified to practice on the basis of their results in actual practice.
Krause, Merton S.; Lutz, Wolfgang; and Saunders, Stephen M., "Empirically Certified Treatments or Therapists: The Issue of Separability" (2007). Psychology Faculty Research and Publications. 309.
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