The Progressive Cascading Model (PCM) is a competency-based approach for training novice therapists in exposure therapy techniques. It involves multiple tiers of experiential learning tailored to the trainee’s skill level.
Trainees first observe treatment sessions, then act as therapy aids assisting more senior clinicians in carrying out exposures. As competencies develop in areas like case conceptualization and exposure delivery, trainees take on roles as junior co-therapists, independent therapists, and eventually supervisors mentoring the more junior trainees.
Throughout the process, trainees receive layered supervision and feedback from both licensed providers and peers at various stages of the cascading model.
The PCM aims to provide an intensive yet scalable framework for graduate students to gain competency in evidence-based exposure methods through modeling, social learning principles, and individualized supervision to enhance disseminating these techniques into community practice after graduation.
Reid, A. M., Guzick, A. G., Balkhi, A. M., McBride, M., Geffken, G. R., & McNamara, J. P. H. (2017). The progressive cascading model improves exposure delivery in trainee therapists learning exposure therapy for obsessive-compulsive disorder. Training and Education in Professional Psychology, 11(4), 260–265. https://doi.org/10.1037/tep0000159
Key Points
- The Progressive Cascading Model (PCM) shows promise as an effective method for training novice therapists in exposure therapy techniques.
- Trainees who went through the PCM showed significant improvements in exposure therapy delivery, including more intense delivery behaviors and fewer cautious/avoidant behaviors.
- The PCM also led to reductions in trainees’ negative beliefs about exposure therapy, disgust sensitivity, and anxiety sensitivity.
- There were no significant differences in training outcomes between more and less experienced trainees, suggesting the PCM can be effectively implemented regardless of prior training.
- The PCM aligns with the competency-based education model in training professionals and may help address poor dissemination of exposure therapy. Further research with comparison groups is still needed.
Rationale
Exposure therapy is a highly efficacious treatment for anxiety disorders, yet many therapists fail to implement it or do so suboptimally in community settings (Higa-McMillan et al., 2016; Hipol & Deacon, 2013).
Researchers believe insufficient graduate-level training in exposure techniques significantly contributes to this problem (Shafran et al., 2009; Weissman et al., 2006).
The Progressive Cascading Model (PCM) was developed as a competency-based method to train novice therapists in exposure therapy (Balkhi et al., 2016), but empirical evaluation of its effectiveness was still needed.
Method
Forty-two trainee therapists completing a 5-6 month rotation at a specialty OCD clinic were trained in the PCM model.
The PCM utilizes experiential and social learning theory across increasing trainee responsibility tiers. It begins with didactics on exposure therapy principles and debunking myths.
Trainees then observe sessions, act as exposure aids to experienced clinicians, then junior co-therapists before independent practice and supervision roles.
Movement between tiers is based on regular evaluations by licensed supervisors. Peer-to-peer feedback and live modeling provide layered learning.
The training experience guided by the PCM is described in more detail by Balkhi et al. (2016).
Procedure
The 42 trainees completed rotations averaging 5-6 months where they implemented exposure therapy. Trainees treated approximately 11 OCD patients each, though exposure hours are unknown.
Patients typically had severe OCD (Yale-Brown scores of 26-27) and around one comorbid condition like depression.
Trainees worked with a mix of around six youth and five adult patients across their rotation. Cotherapy with a supervisor occurred constantly for 26% of trainees, often for 52%, sometimes for 19%, and rarely for 2% – allowing for layered supervision.
Sample
Mostly female psychology graduate students and pre/post-doctoral fellows in clinical psychology programs, with an average age of 27 years old.
Measures
Trainees reported on exposure therapy behaviors, beliefs about exposure, and personal sensitivities before and after training:
- Exposure Therapy Delivery Scale (ETDS): An 18-item self-report scale assessing the frequency of intense (α = .93) and cautious (α = .81) therapist behaviors when implementing exposure therapy.
- Exposure Therapy Case Vignette (ETCV): Assesses intended distress reducing (α = .91), safety acquiescence (α = .88), and intense exposure delivery behaviors via therapist responses to a hypothetical exposure therapy scenario.
- Therapist Beliefs About Exposure Scale (TBES): A 21-item measure of therapist attitudes towards exposure therapy with strong psychometrics (α = .84).
- Anxiety Sensitivity Index-3 (ASI-3): An 18-item scale evaluating fear of anxiety-related sensations (α = .84).
- Disgust Scale-Revised (DS-R): A 25-item measure of disgust sensitivity across domains like contamination (α = .69).
Statistical Measures
Repeated-measures MANOVAs were used to assess pre-post changes on target variables and differences based on trainee experience level.
Results
- There were significant increases in self-reported intense exposure delivery behaviors (p = .026) and decreases in cautious delivery behaviors (p < .001) following PCM training.
- Negative beliefs about exposure therapy (p < .001) and disgust sensitivity (p = .010) also decreased significantly.
- There were no differences based on trainee experience.
Insight
The Progressive Cascading Model significantly improved the quality of exposure therapy delivery and attitudes/sensitivities related to utilizing exposure techniques among trainee therapists.
After going through the PCM program, trainees reported that they delivered exposures more effectively – they used more methods to intensify the exposures and confront patients’ fears thoroughly. They also relied less on cautious behaviors that weaken exposures or make patients too comfortable.
Beyond real therapy skills, the PCM also improved the trainees’ own comfort levels and attitudes about exposure techniques.
Their worries, doubts, or hesitations about using exposure went way down after observing mentors and trying it themselves. Things like feeling disgusted or avoiding triggers didn’t get in the way as much anymore.
Strengths
- Use of repeated pre-post measurements to assess changes throughout training
- Inclusion of self-report and vignette measures to assess multiple aspects of exposure therapy delivery
- Focus on novice therapists still in training rather than changing entrenched practices of working clinicians
- Measurement of therapist factors influencing adoption of exposure in addition to skills
Limitations
- Lack of a control group limits the ability to attribute changes directly to PCM training vs. maturation or general clinical experiences
- Small sample size from a single specialty OCD clinic may not generalize to other settings/populations
- Self-report measures prone to social desirability biases about exposure competency
Implications
The PCM model utilizes experiential and social learning theory to provide layered levels of exposure therapy training tailored to trainees’ needs.
The data suggest it can enhance competency in exposure techniques regardless of prior experience. This has important implications for dissemination, given graduate school is a critical time for shaping therapists’ attitudes and utilization of treatments.
The PCM provides a roadmap for competency-based education in exposure therapy that training programs could readily implement.
If results hold in larger controlled trials, graduate programs should consider implementing this competency-based training model to increase the use of this efficacious yet rarely utilized treatment.
Clinics with expertise in exposure therapy could provide supervised PCM rotations. Future research should examine the sustainability of gains post-training and feasibility across diverse service settings.
Note: The PCM was developed at a clinic which specializes in OCD treatment, thus future research will need to test how well this training model translates to other clinical populations that warrant exposure therapy.
References
Primary reference
Reid, A. M., Guzick, A. G., Balkhi, A. M., McBride, M., Geffken, G. R., & McNamara, J. P. H. (2017). The progressive cascading model improves exposure delivery in trainee therapists learning exposure therapy for obsessive-compulsive disorder. Training and Education in Professional Psychology, 11(4), 260–265. https://doi.org/10.1037/tep0000159
Other references
Balkhi, A. M., Reid, A. M., Guzick, A. G., Geffken, G. R., & McNamara, J. P. H. (2016). The progressive cascading model: A scalable model for teaching and mentoring graduate trainees in exposure therapy. Journal of Obsessive-Compulsive and Related Disorders, 9, 36–42. https://doi.org/10.1016/j.jocrd.2016.02.005
Higa-McMillan, C. K., Kotte, A., Jackson, D., & Daleiden, E. L. (2016). Overlapping and non-overlapping practices in usual and evidence-based care for youth anxiety. The Journal of Behavioral Health Services & Research. Advance online publication. https://doi.org/10.1007/s11414-016-9502-2
Hipol, L. J., & Deacon, B. J. (2013). Dissemination of evidence-based practices for anxiety disorders in Wyoming: A survey of practicing psychotherapists. Behavior Modification, 37(2), 170–188. https://doi.org/10.1177/0145445512458794
Shafran, R., Clark, D. M., Fairburn, C. G., Arntz, A., Barlow, D. H., Ehlers, A., Freeston, M., Garety, P. A., Hollon, S. D., Ost, L. G., Salkovskis, P. M., Williams, J. M. G., & Wilson, G. T. (2009). Mind the gap: Improving the dissemination of CBT. Behaviour Research and Therapy, 47(11), 902-909. https://doi.org/10.1016/j.brat.2009.07.003
Weissman, M. M., Verdeli, H., Gameroff, M. J., Bledsoe, S. E., Betts, K., Mufson, L., Fitterling, H., & Wickramaratne, P. (2006). National survey of psychotherapy training in psychiatry, psychology, and social work. Archives of General Psychiatry, 63(8), 925–934. https://doi.org/10.1001/archpsyc.63.8.925
Keep Learning
Here are some suggested discussion questions for a course focused on therapist training and dissemination of evidence-based treatments:
- What personal and contextual barriers have you observed that prevent therapists from utilizing exposure techniques?
- How might directly addressing trainees’ anxieties about exposure therapy through PCM-style training increase willingness to use these methods?
- What benefits or challenges do you foresee in implementing progressive cascading style models within current graduate program structures?
- Would a competency-based training approach like the PCM better prepare graduates to provide gold-standard care compared to more standardized curricula? What key competencies do you think all clinical trainees should demonstrate before graduation, regardless of therapeutic orientation?
- How sustainable do you think gains in clinical skills and attitudes from an intensive PCM rotation would be if not reinforced after trainees leave that specialty setting? What types of continuing education or consultation practices could help cement longer-term changes?
