[6]: 240 Acceptance and commitment therapy invites people to open up to unpleasant feelings, not to overreact to them, and not to avoid situations that cause them.
ACT helps the individual get in contact with a transcendent sense of self, "self-as-context"—the one who is always there observing and experiencing and yet distinct from one's thoughts, feelings, sensations, and memories.
ACT tries to help the individual clarify values and then use them as the basis for action, bringing more vitality and meaning to life in the process, while increasing psychological flexibility.
A 2005 meta-analysis showed that the six ACT principles, on average, account for 16–29% of the variance in psychopathology (general mental health, depression, anxiety) at baseline, depending on the measure, using correlational methods.
The authors concluded ACT is efficacious for all conditions examined, including anxiety, depression, substance use, pain, and transdiagnostic groups.
The British Association for Behavioural and Cognitive Psychotherapies (BABCP) has a large special interest group in ACT, with over 1,200 members.
[34][page needed] In the late 1980s empirical limitations and philosophical misgivings of the second wave gave rise to Steven Hayes' ACT theory which modified the focus of abnormal behaviour away from the content or form towards the context in which it occurs.
[34][page needed] People's rigid ideas about themselves, their lack of focus on what is important in their life, and their struggle to change sensations, feelings or thoughts that are troublesome only serve to create greater distress.
These treatments tend to seek the construction of broad, flexible and effective repertoires over an eliminative approach to narrowly defined problems, and to emphasize the relevance of the issues they examine for clinicians as well as clients.
This training process, oriented towards the development of mindfulness, acceptance, and valued skills in non-clinical settings such as businesses or schools, has also been investigated in a handful of research studies with good preliminary results.
[37][page needed] The emphasis of ACT on ongoing present moment awareness, valued directions and committed action is similar to other psychotherapeutic approaches that, unlike ACT, are not as focused on outcome research or consciously linked to a basic behavioral science program, including approaches such as Gestalt therapy, Morita therapy, and others.
[41] Wilson, Hayes & Byrd explored at length the compatibilities between ACT and the 12-step treatment of addictions and argued that, unlike most other psychotherapies, both approaches can be implicitly or explicitly integrated due to their broad commonalities.
ACT and 12-step both encourage the pragmatic utility of cultivating a transcendent sense of self (higher power) within an unconventional, individualized spirituality.
[43] In a 2012 blog post, psychologist James C. Coyne criticized the process and studies initially used by the APA to favorably evaluate ACT for the treatment of psychosis in its labeling system for evidence-based medicine.
[44][45] The main study used (Bach and Hayes, 2002) was alleged not to have clearly specified its hypothesis—that ACT reduces rehospitalization—in advance of the conducted analysis: a practice in which researchers retrospectively cherry-pick the metric showing the largest claim-supporting change post-treatment.
[46] In 2013, psychologist Jonathan W. Kanter said that Hayes and colleagues "argue that empirical clinical psychology is hampered in its efforts to alleviate human suffering and present contextual behavioral science (CBS) to address the basic philosophical, theoretical and methodological shortcomings of the field.
CBS represents a host of good ideas but at times the promise of CBS is obscured by excessive promotion of Acceptance and Commitment Therapy (ACT) and Relational Frame Theory (RFT) and demotion of earlier cognitive and behavior change techniques in the absence of clear logic and empirical support.
However, the study is limited by the highly heterogeneous nature of the outcome variables used in the analysis, which tends to increase the number needed to treat (NNT) to replicate the effect size reported.