Cognitive-Behavioral Therapy

What follows is a discussion of this quotation from the current APA Practice Guidelines:
"Cognitive behavioral therapy and interpersonal therapy are the psychotherapeutic approaches that have the best documented efficacy in the literature for the specific treatment of major depressive disorder, although rigorous studies evaluating the efficacy of psychodynamic psychotherapy have not been published".

I have used this quotation to argue that CBT has no scientific basis (since for all practical purposes science that is not published doesn't exist), but some mental health professionals say I haven't interpreted the quotation correctly. Here is an example:

CBT I

I just wanted to point out that cognitive-behavioural therapy, interpersonal therapy and psychodynamic psychotherapy are three separate and distinct treatment approaches, which are meant to be considered independendently from one another in this quotation. Yes, and none of them have supporting scientific evidence and none of them refer to a theoretical core, a basic requirement for any scientific field. Consequently it doesn't matter how many ways one cuts this debate up, psychology remains an unscientific pursuit.

Thank you for writing.

My excuse for this brief reply was that I was doing something interesting and didn't want to break away, also I realized a longer reply would use more words to make the same point. But my correspondent refused to be brushed off.

CBT II

No, I'm sorry.

You have misinterpreted this quotation and used it as evidence suggesting that there is an acknowledgement on the part of the academic community that there is a lack of evidence supporting the efficacy of CBT. Regardless of the actual empirical status of CBT, you are misrepresenting this information as saying something it is not. In this exchange with you I am not concerned over the scientific status of psychology, simply that you have misrepresented important information. Please do not try to change the topic of this exchange. I agree with you that topicality is crucial. The topic is whether psychology is scientific.

Here is the quotation under discussion, from the current APA Practice Guidelines:

"Cognitive behavioral therapy and interpersonal therapy are the psychotherapeutic approaches that have the best documented efficacy in the literature for the specific treatment of major depressive disorder, although rigorous studies evaluating the efficacy of psychodynamic psychotherapy have not been published".

Let's say for the sake of argument that the term "psychodynamic psychotherapy" (hereafter PDP) doesn't refer to CBT at all, and that they are unrelated approaches. To support this position, an obvious first step would be to look up the terms CBT and PDP in something other than a dictionary [for reasons explained here]:

Psychodynamic Psychotherapy (Wikipedia)

"Psychodynamic psychotherapy is a form of depth psychology, the primary focus of which is to reveal the unconscious content of a client's psyche in an effort to alleviate psychic tension. In this way, it is similar to psychoanalysis, however, psychodynamic therapy tends to be more brief and less intensive than psychoanalysis. It also relies on the interpersonal relationship between client and therapist more than other forms of depth psychology. In terms of approach, this form of therapy also tends to be more eclectic than others, taking techniques from a variety of sources, rather than relying on a single system of intervention. It is a focus that has been used in individual psychotherapy, group psychotherapy, family therapy, and to understand and work with institutional and organizational contexts."

Cognitive-Behavioral Therapy (Wikipedia)

"Cognitive behavioral therapy (or cognitive behavior therapy, CBT) is a psychotherapeutic approach that aims to influence problematic and dysfunctional emotions, behaviors and cognitions through a goal-oriented, systematic procedure. CBT can be seen as an umbrella term for therapies that share a theoretical basis in behavioristic learning theory and cognitive psychology, and that use methods of change derived from these theories."

Okay, based on these definitions, and assuming I haven't chosen unrepresentative ones, it seems that, although there is some overlap between the definitions, PDP tends to look into the emotional roots of a problem, while CBT focuses on changing immediate behaviors or symptoms, without spending too much time analyzing causes.

To put it simply and assuming I haven't misinterpreted the terms, PDP looks into causes, and CBT focuses on effects.

If I understand your position, it is that I have misinterpreted the APA Practice Guidelines quotation, and that the latter phrase "studies [...] have not been published" refers only to PDP, not to CBT.

Here's my response. First, the quotation describes CBT and "interpersonal therapy" together as "psychotherapeutic approaches," as though they can be discussed as a unit. This association is borne out in the definition of the terms. But PDP is also and self-evidently a "psychotherapeutic approach," differing only in specifics from CBT and "interpersonal therapy" which are grouped in the quotation.

Second, the quotation taken as a whole says that CBT has "the best documented efficacy" among alternatives, among which are PDP. One might respond that the comparison between CBT and PDP is not explicit in the quotation, but if that were true, why does the quotation have a reference to PDP? The reference is present either because CBT is being grouped with PDP, or CBT is being contrasted to PDP. If neither of these were true, the reference to PDP would not be present.

If CBT and PDP are being grouped, then the phrase "studies [...] have not been published" tells us that there is no scientific support for either one.

If instead CBT and PDP are being contrasted, then the phrase "best documented efficacy" is made in contrast to something that hasn't been studied scientifically, consequently CBT is not being defended in any scientific sense, and the author of the passage seems not to care about this issue when asserting "best documented efficacy".

Under either of these interpretations, it is clear that the quotation offers the reader no evidentiary basis for preferring CBT over PDP or anything else. Within the quotation there is no scientific basis to support CBT and PDP taken as though they were related, and there is no scientific basis to argue for the ascendancy of one over the other.

Further, apart from this particular quotation, our discussion misses the point that there is very poor evidence for either CBT or PDP, and in that sense we are wandering away from the topic. There are very serious systematic difficulties in all psychological studies, including a consistent disregard for the null hypothesis and the placebo effect, a requirement to respect the rights of experimental subjects, and the extreme difficulty of designing a rigorous study of human beings in a way that doesn't violate ethical standards.

My original reason for using the quotation was to point out the relaxed posture toward evidence that permeates the field of psychology. And it seems no matter how one interprets the quotation, it tells us that arguments for CBT or for PDP are based on something other than rigorous, repeatable scientific evidence.

A concise translation of the quotation might be, "We know CBT is better than PDP, but PDP hasn't been evaluated scientifically." On that basis, my original interpretation is justified — it reveals the shaky evidentiary basis for CBT.

A true scientific evaluation of CBT, one never undertaken and unlikely ever to be undertaken, would compare it to a sham therapy, in a rigorously designed double-blind study, one in which neither the experimenters, the therapists nor the subjects would know to which group a particular subject belonged. This experimental design would address the null hypothesis and the placebo effect, two issues regularly ignored in psychological studies.

I think most mental health professionals would react to this proposal by saying, "That's ridiculous! It creates an absurd, unrealistically high standard of evidence, and it suggests that psychological treatments can never be studied in a meaningful way."

I have to agree — it does just that.