Which Therapy Is Best?

Chambless, D.L., & Hollon, S.D. (1998). Defining empirically supported therapies. Journal of Consulting and Clinical Psychology, 66, 7-18.

Overview:

Therapies

Psychotherapy refers to any sort of systematic treatment of psychological problems. Psychotherapists use many different treatment methods and may combine treatments in some situations. Insight therapies are "talking" therapies; patients discuss problems with a therapist who is trained to lead the discussion in some particular way. Insight therapies include psychoanalysis, client-centered (or Rogerian) therapy, cognitive therapy, and group therapy. Behavior therapies are specifically designed to help people change their behavior. Behavior therapies include systematic desensitization, aversion therapy, and biofeedback training. Biological therapies are designed to change physiology that may be contributing to the psychological problem. Biological therapies include drug treatment (or psychopharmacotherapy), electroconvulsive shock therapy, and psychosurgery. In addition, unconventional therapies, such as aromatherapy and rebirthing, are becoming more and more popular every day.

How do you know which therapy is best for treating which psychological problem? Certainly drugs aren't the answer to every problem, but certain drugs can be extremely effective in treating depression. Similarly, systematic desensitization works well for treating phobias but may not be as effective in treating marital difficulties.

Clinical psychologists use a variety scientific methods to evaluate the efficacy of different therapies. But there are many research issues that either aren't or can't be addressed in many studies. For example, comparing some therapy to a no-treatment control group is important for determining whether the therapy is more effective than doing nothing at all. But it is unethical to deny a potentially useful therapy for the sake of research. As well, empirical studies may show statistical significance but is the therapy clinically significant? Psychologist have struggled for many years to determine a set of criteria for determining whether some therapy is effective. Chambless and Hollon (1998) present a set of criteria for defining empirically supported therapies that researchers are beginning to use in examining the efficacy of new (and old) therapies.

Article Summary

What therapy is best for what type of psychological problem? Researchers, therapists, and clients receiving therapy are all interested in answers to this question. Chambless and Hollon (1998) present a set of criteria for determining empirical support for different therapies. Their criteria are based on scientific methods as well as several task forces on clinical research.

Chambless and Hollon state that therapy must be empirically evaluated in a controlled research setting in order to determine whether any effects are due to the therapy and not extraneous factors, such as simply the passage of time, idiosyncrasies of clients, and idiosyncrasies of therapists.

Chambless and Hollon's criteria for empirical support are:

The therapy must be compared with a no-treatment control group, alternative therapy, or placebo.

The therapy must be more beneficial than no therapy or placebo and at least equivalent to an alternative, established therapy. Chambless and Hollon discuss issues related to research design and sample size that are important for making these types of comparisons.

The empirical study must use sound scientific methods.

Chambless and Hollon emphasize the importance of research methodology. The sample must be carefully selected and completely described to allow for generalization. The therapy must be thoroughly described and adhered to in its implementation. The outcome measures must be appropriate for determining both short-term and long-term change. The outcome measures must be analyzed appropriately, including analyzing for possible therapist effects and examining power.

The therapy must be replicated.

Chambless and Hollon argue that, to be considered efficacious, a therapy must be replicated in at least two independent research settings, and any conflict results must be completely resolved. Therapies empirically examined in only one setting are described by Chambless and Hollon as possibly efficacious. Chambless and Hollon term therapies that are found to be superior to an alternative therapy or to a placebo (drug or psychological) in at least two independent research settings efficacious and specific.

Chambless and Hollon conclude their position paper by encouraging the researchers who's work follows their article to apply these criteria in their reviews and to challenge any criteria with which the researchers disagree. Although not adhered to by all the researchers, the entire special issue is an interesting and informative compendium of attempts to define empirically supported therapies for many different psychological problems.

For Instructors

Links to the Lecture

Critical evaluation of a new therapy is difficult to achieve - most people (including students) are quick to accept a new therapy based on very little evidence of efficacy. Richard Viken (1992) presents his class with an absurd pseudotherapy and demonstrates how it can be shown to be "effective." VikenŐs therapy is "Norwegian acupuncture" and it consist of the student applying pressure on the left elbow while mumbling an incantation in Norwegian. He demonstrates large pretest-posttest effects on various measures when selecting extreme groups (such as mood elevation in students who report a very sad mood at the pretest). Viken then uses these results to discuss issues in determining efficacy.

Viken, R.J. (1992). Therapy evaluation: Using an absurd pseudotreatment to demonstrate research issues. Teaching of Psychology, 19, 108-110.

For Students

About the Authors

Dianne Chambless teaches clinical psychology at the University of North Carolina at Chapel Hill. Steven Hollon is a professor at Vanderbilt University.

About the Journal

This article is the lead article in a special issue of the Journal of Consulting and Clinical Psychology on evaluating psychological treatments. Check out some of the articles in this special issue. As well, this article builds on the work of the APA Division 12 (Clinical Psychology) Task Force for Psychological Intervention Guidelines. A report from this task force is available from their Document Repository.

Links to Life

Need a therapist? Select the type of therapist you want (behavioral, counseling, holistic, etc.) and The Therapy Directory will point you toward a therapist. There aren't many people registered on this internet directory yet, but the site is interesting in terms of the types of therapists who are available. Here is another Therapist Directory that is a bit less snazzy in appearance and style but lists psychologists by state.

The APA provides a set of very useful guidelines for deciding on therapy and finding a psychologist.

On-line psychotherapy is available from Dr. Pies, a clinical psychologist, Ask Siggy, from the Therapist Directory described above, and Eliza, a virtual Rogerian psychologist. As well, there is an incredible wealth of on-line psychological resources - check out Dr. John Grohol's megalist of mental health resources.