Home › ACT › Research Resources and Publications › Empirical and Non-Empirical Publications › Empirical Studies

Outcome Studies

August 6, 2005 - 2:14pm — Steven Hayes

Randomized Controlled Trials, Controlled Time Series Designs, and Within Group Designs by Year

Under Review

In Press

  • Ruiz, F. J. & Luciano, C. (In Press). Eficacia de la terapia de aceptación y compromiso (ACT) en la mejora del rendimiento ajedrecístico de jóvenes promesas. Acceptance and commitment therapy (ACT) and improving performance in bright youth hopes chess-players. Psicothema.

2009

2008

  • Lillis, J. (2008). Acceptance and Commitment Therapy for the treatment of obesity-related stigma and sustained weight loss. Unpublished doctoral dissertation. University of Nevada, Reno.
  • Vowles, K. E., & McCracken, L. M. (2008). Acceptance and values-based action in chronic pain: A study of effectiveness and treatment process. Journal of Consulting and Clinical Psychology, 76(3), 397-407.
  • Wicksell, R.K., Ahlqvist, J., Bring, A., Melin, L. & Olsson, G.L. (2008). Can exposure and acceptance strategies improve functioning and life satisfaction in people with chronic pain and whiplash-associated disorders (WAD)? A randomized controlled trial. Cognitive Behaviour Therapy, 37(3), 1-14.
    Included people (adults) with longstanding pain due to whiplash (WAD). A 10-session protocol was compared with a wait list control group, and found significant improvements following treatment in functioning and life satisfaction, as well as in psychological flexibility (as measured with PIPS).

2007

  • Braekkan, K.C. (2007). An acceptance and commitment therapy intervention for combat veterans with posttraumatic stress disorder: Preliminary outcomes of a controlled group comparison. Unpublished doctoral dissertation. Spalding University.
  • Gregg, J. A., Callaghan, G. M., Hayes, S. C., & Glenn-Lawson, J. L. (2007). Improving diabetes self-management through acceptance, mindfulness, and values: A randomized controlled trial. Journal of Consulting and Clinical Psychology, 75(2), 336-343.
    RCT showing that ACT + patient education is significantly better than patient education alone in producing good self-management and better blood glucose levels in lower SES patients with Type II diabetes. Effects at follow up are mediated by changes in self-management and greater psychological flexibility with regard to diabetes related thoughts and feelings.
  • Lillis, J., & Hayes, S. C. (2007). Applying acceptance, mindfulness, and values to the reduction of prejudice: A pilot study. Behavior Modification, 31(4), 389-411.
    Undergraduates enrolled in two separate classes on racial differences were exposed Acceptance and Commitment Therapy and an educational lecture drawn from a textbook on the psychology of racial differences in a counterbalanced order. Results indicate that only the ACT intervention was effective in increasing positive behavioral intentions at post and a 1-week follow-up. These changes were associated with other self-reported changes that fit with the ACT model.
  • Luoma, J. B., Hayes, S. C., Twohig, M. P., Roget, N., Fisher, G., Padilla, M., Bissett, R., & Kohlenberg, B. (2007). Augmenting continuing education with psychologically focused group consultation: Effects on adoption of group drug counseling. Psychotherapy: Theory, Research, Practice, Training, 44(4), 463–469.
    Augmenting continuing education with psychologically-focused group consultation: Effects on adoption of Group Drug Counseling. Psychotherapy Theory, Research, Practice, Training. An ACT-based supervision group following training in Group Drug Counseling increased adoption in drug and alcohol counselors.
  • Páez, M., Luciano, M. C., & Gutiérrez, O. (2007). Tratamiento psicológico para el afrontamiento del cáncer de mama. Estudio comparativo entre estrategias de aceptación y de control cognitivo. [Psychological treatment for breast cancer. Comparison between acceptance based and cognitive control based strategies] Psicooncología, 4, 75–95.
  • Pellowe, M.E. (2007). Acceptance and commitment therapy as a treatment for dysphoria . Unpublished doctoral dissertation. University of Wyoming.
  • Twohig, M. P., Shoenberger, D., & Hayes, S. C. (2007). A preliminary investigation of acceptance and commitment therapy as a treatment for marijuana dependence in adults. Journal of Applied Behavior Analysis, 40, 619-632.
    A multiple baseline showing ACT reducing the use of marijuana in 3 clients. 2 relapsed to a degree at follow up.
  • Wicksell R.K, Melin, L. & Olsson, G.L. (2007). Exposure and acceptance in the rehabilitation of children and adolescents with chronic pain. European Journal of Pain, 11, 267-274.
    Open trial with 14 adolescents. Good outcomes that continue to improve through follow up.

2006

  • Blackledge, J. T., & Hayes, S. C. (2006). Using Acceptance and Commitment Training in the Support of Parents of Children Diagnosed with Autism. Child & Family Behavior Therapy, 28(1), 1-18.
    Pre – post study shows that ACT workshop helps parents cope with the stress of raising autistic children.
  • Gaudiano, B. A., & Herbert, J. D. (2006). Acute treatment of inpatients with psychotic symptoms using Acceptance and Commitment Therapy: Pilot results. Behaviour Research & Therapy, 44(3), 415-437.
    This study replicates the Bach and Hayes study with better measures and a better control condition. Good results esp. on measures of overt psychotic behavior (the BPRS). Mediational analyses fit the ACT model and are described in more detail in Gaudiano, B. A., & Herbert, J. D. (2006). Acute treatment of inpatients with psychotic symptoms using Acceptance and Commitment Therapy: Pilot results. Behaviour Research & Therapy, 44(3), 415-437.
  • Gratz, K. L., & Gunderson, J. G. (2006). Preliminary data on an acceptance-based emotion regulation group intervention for deliberate self-harm among women with Borderline Personality Disorder. Behavior Therapy, 37(1), 25-35.
    Randomized trial comparing and ACT / DBT combo to TAU. Very strong outcomes on self-harm and other measures. Follow-up is not in this manuscript -- will follow in another publication. The buzz is that outcomes continue to improve; along with acceptance scores.
  • Lundgren, A. T., Dahl, J., Melin, L., & Kies, B. (2006). Evaluation of Acceptance and Commitment Therapy for drug refractory epilepsy: A randomized controlled trial in South Africa. Epilepsia, 47, 2173-2179.
    RCT with 27 drug resistant epileptics comparing 9 hours of ACT – individual and group -- to supportive therapy. Reduction of seizures to near zero level; maintenance for a year. Quality of life improves continuously through the follow up. Mediational analyses fit the ACT model and are described in more detail in Lundgren, T., Dahl, J., & Hayes, S. C. (2008). Evaluation of mediators of change in the treatment of epilepsy with Acceptance and Commitment Therapy. Journal of Behavior Medicine.
  • Rosenqvist, D. & Sand, J. (2006). Mindfulness based smoking cessation for groups - an explorative study. Thesis at the Lund University, Sweden.
    6 acceptance and mindfulness group sessions during 35 days including individual homework assignments. 8 of 10 participants completed the program. At 1 mo follow up 50 percent (of 8 completers) were non-smokers, and the rest showed a decrease in smoking at a rate between 45 and 75 percent. Increase of the acceptance aspect of mindfulness was correlated with non-smoking.
  • Twohig, M. P.; Hayes, S. C., & Masuda, A. (2006). Increasing Willingness to Experience Obsessions: Acceptance and Commitment Therapy as a Treatment for Obsessive-Compulsive Disorder. Behavior Therapy, 37(1), 3-13.
    Multiple baseline showing very large reductions in OCD with an 8 session ACT protocol without in session exposure.
  • Twohig, M. P., Hayes, S. C., & Masuda, A. (2006). A preliminary investigation of acceptance and commitment therapy as a treatment for chronic skin picking. Behaviour Research and Therapy, 44, 1513-1522.
    Multiple baseline. Good effects at post but less so at follow up.
  • Woods, D. W., Wetterneck, C. T., & Flessner, C. A. (2006). A controlled evaluation of Acceptance and Commitment Therapy plus habit reversal for trichotillomania. Behaviour Research and Therapy.
    A small randomized trial (25 completers) comparing ACT plus habit reversal to a wait list. Wait list subjects then receive ACT/HR. Solid hair pulling, anxiety, and depression outcomes, maintained at a 3 month follow up. Wait list participants also improve once they get ACT. AAQ moves and correlates well with outcomes.
  • Williams, L.M. (2006). Acceptance and commitment therapy: An example of third-wave therapy as a treatment for Australian Vietnam War veterans with posttraumatic stress disorder: Unpublished dissertation, Charles Sturt University, Bathurst, New South Wales.

2005

  • McCracken, L. M., Vowles, K. E., & Eccleston, C. (2005). Acceptance-based treatment for persons with complex, long standing chronic pain: A preliminary analysis of treatment outcome in comparison to a waiting phase. Behaviour Research and Therapy, 43, 1335-1346.
    108 chronic pain patients with a long history of treatment are followed through an ACT-based 3-4 week residential treatment program. Measures improved from initial assessment to pre-treatment on average only 3% (average of 3.9 month wait), but improved on average 34% following treatment. 81% of these gains were retained through a 3 month follow up. Changes in acceptance predicted positive changes in depression, pain related anxiety, physical disability, psychosocial disability, and the ability to stand. Positive outcomes were also seen in a timed walk, decreased medical visits, daily rest due to pain, pain intensity, and decreased pain medication use.

2004

  • Branstetter, A. D., Wilson, K. G., Hildebrandt, M., & Mutch, D. (2004). Improving psychological adjustment among cancer patients: ACT and CBT. Paper presented at the Association for Advancement of Behavior Therapy, New Orleans.
    Large randomized trial showing that ACT is more helpful than traditional CBT in dealing with end stage cancer and works through a different process. Amazing data.
  • Dahl, J., Wilson, K. G., & Nilsson, A. (2004). Acceptance and Commitment Therapy and the treatment of persons at risk for long-term disability resulting from stress and pain symptoms: A preliminary randomized trial. Behavior Therapy, 35, 785-802.
    A small randomized controlled trial shows that a four hour ACT intervention reduced sick day usage by 91% over the next six months compared to treatment as usual in a group of chronic pain patients at risk for going on to permanent disability.
  • Folke F., & Parling, T. (2004). Acceptance and Commitment Therapy in group format for individuals who are unemployed and on sick leave suffering from depression: A randomized controlled trial. Unpublished thesis, University of Uppsala, Uppsala, Sweden.
    RCT showing that ACT significantly reduces depression among workers on sick leave.
  • Gifford, E. V., Kohlenberg, B. S., Hayes, S. C., Antonuccio, D. O., Piasecki, M. M.., Rasmussen-Hall, M. L., & Palm, K. M. (2004). Acceptance theory-based treatment for smoking cessation: An initial trial of Acceptance and Commitment Therapy. Behavior Therapy, 35, 689-705.
    Medium sized randomized controlled trial comparing ACT to nicotine replacement therapy (NRT) as a method of smoking cessation. Quit rates were similar at post but at a one-year follow-up the two groups differed significantly. The ACT group had maintained their gains (35% quit rates) while the NRT quit rates had fallen (less than 10%). Mediational analyses shows that ACT works through acceptance and response flexibility.
  • Hayes, S. C., Wilson, K. G., Gifford, E. V., Bissett, R., Piasecki, M., Batten, S. V., Byrd, M., & Gregg, J. (2004). A randomized controlled trial of twelve-step facilitation and acceptance and commitment therapy with polysubstance abusing methadone maintained opiate addicts. Behavior Therapy, 35, 667-688.
    A large randomized controlled trial was conducted with polysubstance abusing opiate addicted individuals maintained on methadone. Participants (n=114) were randomly assigned to stay on methadone maintenance (n=38), or to add ACT (n=42), or Intensive Twelve Step Facilitation (ITSF; n=44) components. There were no differences immediately post-treatment. At the six-month follow-up participants in the ACT condition demonstrated a greater decrease in objectively measured (through monitored urinalysis) opiate use than those in the methadone maintenance condition (ITSF did not have this effect). Both the ACT and ITSF groups had lower levels of objectively measured total drug use than did methadone maintenance alone.
  • Livheim, F. Acceptance and Commitment Therapy i skolan - att hantera stress: En randomiserad, kontrollerad studie. Unpublished doctoral dissertation, University of Uppsala, Sweden. 2004.
  • Lundgren, A. T. (2004). Development and evaluation of an integrative health model in the treatment of epilepsy: Two randomized controlled trials investigating the effects of a short term ACT intervention, yoga, and attention control therapy in India and South Africa. Unpublished thesis, University of Uppsala, Uppsala, Sweden.
    Two small RCTs (N = 18; and N = 28) comparing a three session ACT protocol (two individual; one group) to two other conditions. As compared to yoga, significantly reduced seizures in the ACT condition; as compared to attention control, significantly reduced seizures and experiential avoidance, and significantly increased quality of life in the ACT condition at a one year follow up.
  • Twohig, M. & Woods, D. (2004). A preliminary investigation of acceptance and commitment therapy and habit reversal as a treatment for trichotillomania. Behavior Therapy, 35, 803-820.
    A series of controlled single case designs show that ACT, and ACT combined with habit reversal helps with hair pulling.

2003

  • Zettle, R. D. (2003). Acceptance and commitment therapy (ACT) versus systematic desensitization in treatment of mathematics anxiety. The Psychological Record, 53(2), 197-215.
    Small randomized controlled trial shows that ACT is about as good as systematic desensitization in reducing math anxiety, but works according to a different process. Systematic desensitization reduced trait anxiety more. ACT results were better for high emotional avoiders. This is the only study so far with a negative effect size for ACT -- in this case in comparison to systematic desensitization.

2002

  • Bach, P. & Hayes, S. C. (2002). The use of Acceptance and Commitment Therapy to prevent the rehospitalization of psychotic patients: A randomized controlled trial. Journal of Consulting and Clinical Psychology, 70 (5), 1129-1139.
    Shows that a three-hour ACT intervention reduces rehospitalization by 50% over a 4 month follow-up as compared to treatment as usual in the seriously mentally ill.

2000

  • Block, J.A. & Wulfert, E. (2000). Acceptance or change: Treating socially anxious college students with ACT or CBGT. The Behavior Analyst Today, 1(2), 3-10.
    Small RCT on the treatment of social anxiety. Compared ACT to Cognitive Behavioral Group Therapy and to a no treatment control. Results indicated that ACT participants evidenced a significant increase in reported willingness to experience anxiety, a significant decrease in behavioral avoidance during public speaking, and a marginally decrease in anxiety during the exposure exercises as compared with the control group. Similar results were found for CBGT, but ACT found greater changes in behavioral avoidance.
  • Bond, F. W. & Bunce, D. (2000). Mediators of change in emotion-focused and problem-focused worksite stress management interventions. Journal of Occupational Health Psychology, 5, 156-163.
    Randomized controlled trial. Shows that ACT is more effective than a previously empirically supported behavioral approach to reducing worksite stress and anxiety, and that both are better than a wait list control.

  • Metzler, C. W., Biglan, A., Noell, J., Ary, D., & Ochs, L. (2000). A randomized controlled trial of a behavioral intervention to reduce high-risk sexual behavior among adolescents in STD clinics. Behavior Therapy, 31, 27-54.
    Components from ACT were included as component of a successful program to reduce high risk sexual behavior in adolescents.

1999 and earlier(First ACT Book Appears in 1999)

  • Zettle, R. D., & Raines, J. C. (1989). Group cognitive and contextual therapies in treatment of depression. Journal of Clinical Psychology, 45, 438-445.
    Small controlled trial. Shows that ACT is as effective as cognitive therapy for depression when presented in a group format, and that it works by a different process. The effect sizes in favor of ACT are about .6
  • Singer, G. H., Irvine, A. B., & Irvin, L. K. (1989). Expanding the focus of behavioral parent training. In G. Irvin (Ed.), Support for caregiving families: Enabling positive adaptation to disability (pp. 85-102). Baltimore, MD, Paul H. Brookes.
    RCT on the distress felt by families of disabled children. Good outcomes. ACT included as a treatment for depression.
  • Zettle, R. D. & Hayes, S. C. (1986). Dysfunctional control by client verbal behavior: The context of reason giving. The Analysis of Verbal Behavior, 4, 30-38.
    Small controlled trial focusing on process differences between ACT and CT. Only the Hamilton outcome is mentioned in this manuscript. Shows that ACT is more effective that cognitive therapy for depression when presented in an individual format, and that it works by a different process
‹ Experimental Psychopathology and Component StudiesupReviews of the Empirical Literature ›