Practice-Based Psychotherapy Research
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PPRNet Blog: October 2014

Giorgio A. TascaAt the PPRNet conference in November 2012 over 100 psychotherapy clinicians, researchers, and educators were very keen to receive ongoing information about psychotherapy research that is practice-oriented and presented in an easily readable format. And so the PPRNet Blog was born.

About once a month I will review and summarize two or three published psychotherapy research articles. As part of the summary, I will highlight the practice implications of the research.

Because of copyright issues, we cannot post the full text of the articles, but we will provide a link to the abstract on the publisher's web site. I will also post the author's email address. Most authors are very happy to share their work. So if you want a copy of the article send the author an email with a request for a pdf or reprint.

At the bottom of each review you can post a comment, and comment on your colleagues' comments. I will update these as frequently as possible.

If you have ideas for an article to review or a topic you would like to see covered, please send me an email at

Giorgio A. Tasca

blogAre Humanistic-Experiential Therapies Effective? Review and Meta-Analyses

Handbook of Psychotherapy and Behavior Change

Starting in March 2013 I will review one chapter a month from the Handbook of Psychotherapy and Behavior Change in addition to reviewing psychotherapy research articles. Book chapters have more restrictive copy right rules than journal articles, so I will not provide author email addresses for these chapters. If you are interested, the Handbook table of content and sections of the book can be read on Google Books: Handbook on Google Books:

Are Humanistic-Experiential Therapies Effective? Review and Meta-Analyses

Elliott, R.E., Greenberg, L.S., Watson, J. Timulak, L., & Briere, E. (2013). Research on humanistic-experiential psychotherapies. In M.E. Lambert (Ed.), Bergin and Garfield’s Handbook of Psychotherapy and Behavior Change, 6th Edition (pp. 495-538). New York: Wiley.

Humanistic or experiential psychotherapies (HEP) include: person centred therapy, gestalt therapy, emotion-focused therapy, existential psychotherapy, and others. Elliott and colleagues argue that each of these approaches share the characteristic of valuing the centrality of an empathic and therapeutic relationship. That is, an authentic relationship between patient and therapist provides the client with a new and emotionally validating experience. HEP methods that deepen client emotional experiences occur within an empathic relationship, and interpersonal safety is key to enhancing a client’s attention for self awareness and exploration. Despite the long history of research in HEP, these treatments are often used as “control” conditions in outcome studies of psychotherapies – that is, to control for “non-specific” or relationship factors. Elliott and colleagues conducted meta-analyses on the effectiveness of humanistic-experiential therapies. Overall, they included 199 studies of over 14,000 patients. Pre to post treatment effect sizes were large (d = .95), indicating a positive effect HEP across a wide range of clients. (A note on effect sizes: Cohen's d < .20 represents a negligible effect; d = .20 to .49 is a small effect; d = .50 to .79 is a moderate effect; and d > .80 is a large effect). Compared to a wait-list control (62 studies), the positive effect of HEP was significant with a moderate effect size for the difference (d = .76). There were 135 studies that compared HEP to other active forms of psychotherapy. The difference between HEP and non-HEP therapies were trivial and non significant (d = .01). In the 76 studies that compared HEP to cognitive behavioral therapy (CBT), those who received CBT had better outcomes, but the effects were negligible (d = .13). The authors reported that there is enough evidence to indicate that HEP are efficacious for depressive disorders, substance misuse, and relationship problems; and HEP are probably efficacious for anxiety and psychotic disorders.

Practice Implications

The research on outcomes of humanistic-existential psychotherapies (HEP) provides support for the effectiveness of these therapies for a variety of disorders, and provides further support for the importance of the facilitative and relationship factors that help patients get better. Empathy, genuineness, positive regard each comes with research support to indicate their importance to patient outcomes. Elliot and colleagues conclude that the education of psychotherapists is incomplete without greater emphasis on HEP and its facilitative components.

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blogPsychological Interventions for Post Traumatic Stress Disorder

Gerger, H., Munder, T., Gemperli, E., Nuesch, E., Trelle, S., Juni, P., & Barth, J. (2014). Integrating fragmented evidence by network meta-analysis. Relative effectiveness of psychological interventions for adults with post-traumatic stress disorder. Psychological Medicine, doi:10.1017/S0033291714000853.

Gerger and colleagues conducted a network meta-analysis to summarize the evidence on the effectiveness of psychological interventions for post-traumatic stress disorder (PTSD). Psychological trauma is common in the population (between 40% and 90% lifetime prevalence), and many people develop symptoms following the trauma that may turn into PTSD. For example people may re-experience the traumatic event, avoid stimuli related to the traumatic event, or experience increased arousal. Even those who do not meet DSM-IV criteria for PTSD may still have severe impairment and chronic symptoms. Specific interventions for PTSD include exposure to trauma related stimuli or working through cognitions related to the trauma. Non-specific interventions might include supportive therapy or relaxation treatments. As I mentioned in previous blogs, meta-analyses are the best way to summarize the evidence of existing research in order to make clinical decisions about practice. Meta-analyses allow us to pool the effect sizes from individual studies of many patients into an average effect. This method provides the most reliable estimates of the effects of treatments – no single study can be as reliable. Network meta-analysis is a relatively new method that not only allows one to accumulate results from trials that directly compare the same two treatments, but it also allows indirect comparisons of a treatment and another treatment that was tested in a different study. In their network meta-analysis, Gerger and colleagues included 66 studies representing 4,196 patients. Specific treatments included cognitive behavioral therapies (CBT), eye movement desensitization and reprocessing (EMDR), and exposure based therapy (ET). Non-specific interventions included stress management (SM) and supportive therapy (ST). The positive effect of specific interventions (CBT, EMDR, and ET) compared to a wait-list control was large. The positive effect of non-specific interventions (SM, ST) compared to a wait-list control was moderate. There were no differences in effectiveness among the psychological interventions, except EMDR outperformed ST. However, this difference disappeared when only the large scale trials were considered (results from large scale trials tend to be more reliable). Patients with a formal diagnosis of PTSD appear to benefit more from psychological interventions than those with sub-clinical PTSD, though both groups improved.

Practice Implications

Different specific interventions for PTSD (CBT, EMDR, ET) appear to have similar positive benefits with large effects. Indirect interventions show moderately positive effects. Supportive therapy (ST) may be beneficial, but the authors indicated that it is too early to conclude that ST is as effective as direct specific interventions. All patients benefit from psychological interventions, though those with more severe symptoms stand to gain the most. Given the similar outcomes of interventions and the number of effective interventions, researchers are now arguing that factors such as access, acceptability, and patient preference should influence the choice of treatment.

View the Psychological Interventions for Post Traumatic Stress Disorder abstract.
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blogClient Preferences Affect Satisfaction, Completion, and Outcome

Lindheim, O., Bennett, C.B., Trentacosta, C.J., & McLear, C. (2014). Client preferences affect treatment satisfaction, completion, and clinical outcome: A meta-analysis. Clinical Psychology Review, 34, 506-517.

Giving clients a choice about treatments or to receive their preferred treatment might improve treatment outcomes. Preference usually means clients passively receiving the treatment they prefer. Choice involves clients actively making a decision about which treatment option to receive. Clients may also make informed or uninformed preferences and choices. Informed preferences and choices refer to providing clients with information or education about treatment options. Having a choice or getting one’s preference between two or more efficacious treatments might have several beneficial effects. For example, some research shows that treatment preferences positively affect therapeutic alliance, possibly because clients may enter treatment with a more positive outlook about what intervention they receive. Patients receiving a preferred treatment may also have better overall communication with their providers which may lead to better outcomes. In their meta-analysis, Lindheim and colleagues were interested in the effects of client preference or choice on treatment satisfaction, completion, and clinical outcomes. The meta-analysis included 34 different studies. Client preference or choice of treatment was modestly but significantly and consistently related to satisfaction, completion rates, and to client outcomes. Clients who were involved in shared decision making, who chose a treatment condition, or who received their preference had higher satisfaction, increased completion rates, and better clinical outcomes compared to clients who were not involved in the decision, who did not choose, or who did not receive their preference. Setting (inpatient vs outpatient) or diagnosis did not have an effect on these findings.

Practice Implications

The findings highlight the clinical benefits of assessing client preferences and providing treatment options when two or more efficacious options are available. Increasingly, two or more efficacious options are available for common mental disorders like depression and anxiety. Many times, patients prefer psychotherapy over medications, for example. However, whereas medication prescriptions for mental disorders like depression rose dramatically in the past decades, rates of psychotherapy use remained stable or slightly declined. For those disorders for which two or more treatment options have comparable efficacy, client preference should be the deciding factor.

View the Client Preferences Affect Satisfaction, Completion, and Outcome article abstract.
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