Blog
The Psychotherapy Practice Research Network (PPRNet) blog began in 2013 in response to psychotherapy clinicians, researchers, and educators who expressed interest in receiving regular information about current practice-oriented psychotherapy research. It offers a monthly summary of two or three published psychotherapy research articles. Each summary is authored by Dr. Tasca and highlights practice implications of selected articles. Past blogs are available in the archives. This content is only available in English.
This month...

…I blog about therapist variables leading to poor outcomes, aspects of the therapeutic relationship and outcomes, and psychological therapies and patient quality of life.
Type of Research
Topics
- ALL Topics (clear)
- Adherance
- Alliance and Therapeutic Relationship
- Anxiety Disorders
- Attachment
- Attendance, Attrition, and Drop-Out
- Client Factors
- Client Preferences
- Cognitive Therapy (CT) and Cognitive-Behavioural Therapy (CBT)
- Combination Therapy
- Common Factors
- Cost-effectiveness
- Depression and Depressive Symptoms
- Efficacy of Treatments
- Empathy
- Feedback and Progress Monitoring
- Group Psychotherapy
- Illness and Medical Comorbidities
- Interpersonal Psychotherapy (IPT)
- Long-term Outcomes
- Medications/Pharmacotherapy
- Miscellaneous
- Neuroscience and Brain
- Outcomes and Deterioration
- Personality Disorders
- Placebo Effect
- Practice-Based Research and Practice Research Networks
- Psychodynamic Therapy (PDT)
- Resistance and Reactance
- Self-Reflection and Awareness
- Suicide and Crisis Intervention
- Termination
- Therapist Factors
- Training
- Transference and Countertransference
- Trauma and/or PTSD
- Treatment Length and Frequency
June 2018
Is Short-Term Prolonged Exposure Effective to Treat PTSD in Military Personnel?
Foa, E., McLean, C.P., Zang, Y., Rosenfield, D., Yadin, E… Peterson, A. (2018). Effect of prolonged exposure therapy delivered over 2 weeks vs 8 weeks vs present-centered therapy on PTSD symptom severity in military personnel: A randomized clinical trial. Journal of the American Medical Association, 319, 354-364.
Post-traumatic stress disorder (PTSD) can affect 10% to 20% of military personnel returning from combat. PTSD is often chronic and debilitating, and is associated with symptoms that are distressing, that lower quality of life, and that negatively impact family and loved ones. Prolonged exposure therapy (PE) has been tested in the past, and researchers have claimed that it is an efficacious treatment in civilians and veterans. PE is a form of behavior therapy and cognitive behavioral therapy characterized by re-experiencing the most traumatic event through remembering it and engaging with, rather than avoiding reminders of the trauma. In their treatment guidelines, the American Psychological Association (APA) proposed PE as a recommended treatment for PTSD. In this randomized controlled trial, Foa and colleagues assess if providing PE in intensive short time frame (massed exposure; 10 sessions over 2 weeks) was as effective as standard exposure (10 sessions over 8 weeks) for 370 military personnel in the US with PTSD. That is, the authors were interested to see if providing the same amount of therapy based on exposure in a shorter time was just as effective. They also compared the two versions of PE (massed and standard exposure) to two control conditions: present centred therapy (PCT) that is largely supportive therapy that does not rely on exposure to the trauma, and a no treatment control condition. The main outcomes were reductions in level of PTSD symptoms and reductions in PTSD diagnoses at post-treatment and up to 6 months post-treatment. Massed and standard PE were equally effective in reducing symptoms and diagnoses of PTSD compared to no treatment. However, PE was not more effective than PCT in reducing symptoms and diagnoses, and PCT was more effective than no treatment. Overall, reductions in PTSD symptoms and reduction in PTSD diagnoses were modest. Drop out rates were high at about 50% for all conditions.
Practice Implications
Drop out rates were high and outcomes were modest for these short-term psychological treatments for PTSD in military personnel, such that over 60% still had a diagnosis of PTSD at 6 months follow up. And PE therapy did no better than a control condition (PCT) that simply provided support with no exposure to the trauma. These findings are similar to other research in this area. Psychotherapy for trauma may require more time to work, and perhaps different models of understanding and treating the disorder. As Shedler recently remarked, it takes at least 20 sessions/weeks before 50% of clients improve. So it may not be surprising that 2 or 8 weeks of therapy had only a small impact on PTSD symptoms.
May 2015
Is Exposure Necessary to Treat PTSD?
Markowitz, J.C., Petkova, E., Neria, Y., Van Meter, P.E., Zhao, Y., … Marshall, R.D. (2015). Is exposure necessary? A randomized controlled trial of Interpersonal Psychotherapy for PTSD. American Journal of Psychiatry, 172, 1-11.
Post-traumatic stress disorder (PTSD) is a condition caused by experiencing or witnessing a terrifying event. Symptoms may include flashbacks, nightmares and severe anxiety, as well as uncontrollable thoughts about the event. PTSD has a lifetime prevalence of 6.8%, which makes it a highly prevalent disorder. The main technique of empirically validated psychological treatments for PTSD involve exposing patients to safe reminders of the trauma including memories, with the intent of extinguishing the fear responses. This is the basis of cognitive behavioural therapy (CBT) with prolonged exposure, which is a consensus treatment for PTSD. However, not all patients benefit from CBT with prolonged exposure, and such treatment may be too difficult for some patients and therapists to tolerate. Markowitz and colleagues argued that PTSD symptoms reflect interpersonal issues including interpersonal withdrawal, mistrust, and hypervigilence. Interpersonal psychotherapy (IPT) is a time-limited efficacious treatment for depression that was adapted for this study for non-exposure based non-CBT treatment of PTSD. IPT was modified so that the first half of treatment focused on recognizing, naming, and expressing feelings in non-trauma related interpersonal situations. The second half of treatment focused on common IPT themes such as role disputes and role transitions. The authors argued that IPT helps individuals with PTSD gain mastery over social interactions and mobilize social supports. The authors conducted a randomized controlled trial that had a sufficient sample size to test a hypothesis of “non-inferiority”, that is to adequately test if PTSD and exposure based CBT were equally effective. Both treatments were compared to a progressive muscle relaxation (PMR) control condition. In all, 110 participants with chronic PTSD were recruited and randomized to IPT, CBT, or PMR. Most patients reported trauma of 14 years duration from either sexual or physical abuse, and half had a current comorbid depression. All three interventions resulted in large significant reductions in PTSD symptoms. IPT (63%) and CBT (47%) were not significantly different in rates of response (i.e., in which response was defined as 30% improvement in a clinician administered PTSD scale), but IPT had a significantly higher response rate than PMR (38%). Patients with comorbid depression were more likely to drop out of CBT with prolonged exposure than IPT.
Practice Implications
The results of the study suggest that IPT and CBT with exposure were equally effective in reducing symptoms of PTSD. It is important to keep in mind that this is one well-conducted trial that needs to be replicated by independent researchers in order to establish if the findings are truly reliable. Nevertheless, the findings contradict the widespread belief that patients with PTSD require exposure-based treatment in order to improve. IPT may be another option for the treatment of PTSD, especially for patients who cannot tolerate the prolonged exposure. Patients with comorbid depression may have the most difficulty tolerating prolonged exposure therapy, and so they may benefit from IPT as an alternative. IPT may help patients gain abilities in social interactions and social support, which may make it easier for them to spontaneously expose themselves to recollections of trauma.