No ownership of common factors

Comments on the original article, "The efficacy of psychodynamic psychotherapy," by J. Shedler (see record 2010-02208-012). Shedler's informative article raised several issues worthy of comment. His choice of the word distinctive (p. 98) in describing aspects of psychodynamic technique is open to at least two interpretations. On the one hand, distinctive can have a qualitative meaning and indicate the presence of a characteristic that is not shared. For example, a sign in the Bronx Zoo distinguishes birds from all other creatures as follows: "If it has feathers it's a bird, if it doesn't, it isn't." On the other hand, distinctive can have a quantitative meaning and indicate that one practice has more of a common element than another practice. Careful reading of Shedler's article and the article by Blagys and Hilsenroth (2000) that forms the basis of the "seven features that] reliably distinguished psychodynamic therapies from other therapies" (Shedler, 2010, p. 98) shows that Shedler subscribes to the latter, quantitative, definition of distinctive. In other words, the seven features he presented are present in both psychodynamic therapies and the cognitive-behavioral therapies to which he compares them. For example, although Shedler did not mention it, dialectical behavior therapy explicitly focuses on six of the seven features, namely, "focus on affect and expression of emotion," "exploration of attempts to avoid distressing thoughts and feelings," "identification of recurring themes and patterns," "discussion of past experience," "focus on interpersonal relations," and "focus on the therapy relationship" (Shedler, 2010, p. 99). However, in the articles that Blagys and Hilsenroth reviewed, psychodyamic therapists engaged in more of these behaviors than did cognitive-behavioral therapists.