ACT Briefly: Myths and Facts

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If you haven’t seen it for yourself, you may be skeptical that real behavior change is possible in just one or two therapy sessions. After all, that’s not time enough to form a therapeutic relationship. But the reality is that evidence supports the value of brief interventions, including ACT.

Let’s take a look at some myths and facts about brief interventions.

Myth: The benefits of therapy build over time.

This assumption is sometimes referred to as the “dose effect.” The seminal study on this myth was published in 1986 (Howard, Kopta, Krause, & Orlinsky) and found, for starters, that approximately 15 percent of clients experienced some level of improvement before they even arrived to their first session. The benefits of therapy can begin with the decision to seek help. This where we first start to the see the more-is-better myth break down.

Fact: Progress tends to slow significantly after eight sessions.

The same study also found that 50 percent of the total therapeutic benefit in their sample was achieved by the eighth session. Additional benefits were found in longer treatment, but progress slows so noticeably after the eighth session that the cost-effectiveness of additional therapy is called into question.

A more recent study found that clients who underwent brief treatments experienced more rapid rates of change compared with clients who received longer-term treatment. The number of sessions was not a significant predictor of the degree of clinical change (Baldwin, Berkeljon, Atkins, Olsen, & Nielsen, 2009). Over time, rather than increased improvements of the same magnitude, it is not uncommon for client progress to plateau.

Myth: Rapid gains rarely occur in therapy.

According to the data, the most likely outcome is that the client will experience noticeable improvements within the first four hour-long sessions. One study found that 40 to 45 percent of depressed clients exhibited large gains within the first two to four treatment sessions (Doane, Feeny, & Zoellner, 2010; Tang, DeRubeis, Hollon, Amsterdam, & Shelton, 2007).

Similarly impressive results have been reported in clients receiving therapy for post-traumatic stress disorder (52 percent; Doane, Feeny, & Zoellner, 2010) and binge eating (62 percent; Grilo, Masheb, & Wilson, 2006).

Fact: Most clients are short-term clients.

Most clients do not engage in long-term therapy. In a study of more than nine thousand clients, over 85 percent ended treatment by the fifth session. And significantly, the most frequently occurring number of psychotherapy visits in the sample was just one (Brown & Jones, 2005).

Traditional methods typically dedicate the first session of treatment to recording the client’s history and preparing a treatment plan, leaving interventions for later sessions. In light of the fact that many clients never return for a second visit, the introduction of brief interventions may help you to make the most out of session one.

See also: Mindfulness, A Practical Tool For Connecting With Clients​

Myth: Longer-term treatment produces more enduring benefits.

Longer-term treatment may be expected to offer the ongoing support needed to help prevent relapse, but studies suggest this is also a myth.

One study showed that the degree of symptom-reduction and long-term improvement in social functioning was just as great in eight-session treatment as in sixteen-session treatment (Molenaar et al., 2011).

Similar results were found in studies that compared short- and long-term therapy for anorexia (Lock, Agras, Bryson, & Kraemer, 2005), childhood behavior problems (Smyrnios & Kirkby, 1993), post-traumatic stress disorder (Sijbrandij et al., 2007), along with depression and a wide range of anxiety disorders (for a review, see Cape, Whittington, Buszewicz, Wallace, & Underwood, 2010).

Overall, evidence indicates that brief interventions are not only effective, but given client behavior, the time for intervention is often now or never. 

The studies featured here are covered in greater detail in Mindfulness and Acceptance in Social Work: Evidence-Based Interventions and Emerging Applications, edited by Matthew S. Boone, LCSW, 2014. For more on brief interventions in ACT, we recommend the work and events of clinical psychologist, co-founder of ACT, Kirk Strosahl, PhD.

Learn Brief ACT Interventions to Use With Your Clients at Our Upcoming BootCamps!


Baldwin, S., Berkeljon, A., Atkins, D., Olsen, J., & Nielsen, S. (2009). Rates of change in naturalistic psychotherapy: Contrasting dose-effect and good-enough level models of change. Journal of Consulting and Clinical Psychology, 77, 203-211.

Brown, G., & Jones, E. (2005). Implementation of a feedback system in a managed care environment: What are patients teaching us? Journal of Clinical Psychology, 61, 187-198.

Cape, J., Whittington, C., Buszewicz, M., Wallace, P., & Underwood, L. (2010). Brief psychological therapies for anxiety and depression in primary care: Meta-analysis and meta-regression. BMC Medicine, 8, 38.

Doane, L., Feeny, N., & Zoellner, L. (2010). A preliminary investigation of sudden gains in exposure therapy for PTSD. Behaviour Research and Therapy, 48, 555-560.

Grilo, C. M., Masheb, R. M., & Wilson, G. T. (2006). Rapid response to treatment for binge eating disorder. Journal of Consulting and Clinical Psychology, 74, 602-613.

Howard, K., Kopta, S., Krause, M., & Orlinsky, D. (1986). The dose-effect relationship in psychotherapy. American Psychologist, 41, 159-164.

Lackner, J., Gudleski, G., Keefer, L., Krasner, S., Powell, C., & Katz, L. (2010). Rapid response to cognitive behavior therapy predicts treatment outcome in patients with irritable bowel syndrome. Clinical Gastroenterology and Hepatology, 8, 426-432.

Lock, J., Agras, S., Bryson, S., & Kraemer, H. (2005). A comparison of short- and long-term family therapy for anorexia nervosa. Journal of the Academy of Child and Adolescent Psychiatry, 44, 632-639.

Molenaar, P. J., Boom, Y., Peen, J., Schoevers, R. A., Van, R., & Dekker, J. J. (2011). Is there a dose-effect relationship between the number of psychotherapy sessions and improvement of social functioning? British Journal of Clinical Psychology, 50, 268-282.

Sijbrandij, M., Olff, M., Reistsma, J., Carlier, I., de Vries, M., & Gersons, B. (2007). Treatment of acute posttraumatic stress disorder with brief cognitive-behavioral therapy: A randomized controlled trial. American Journal of Psychiatry, 164, 82-90.

Smyrnios, K., & Kirkby, R. (1993). Long-term comparison of brief versus unlimited psychodynamic treatment of children and their parents. Journal of Consulting and Clinical Psychology, 61, 1020-1027.

Tang, T., DeRubeis, R., Hollon, S., Amsterdam, J., & Shelton, R. (2007). Sudden gains in cognitive therapy for depression and depression relapse/recurrence. Journal of Consulting and Clinical Psychology, 75, 404-408.