Acceptance and Commitment Therapy Simply Explained

1. What It Is About

Acceptance and Commitment Therapy, or ACT for short, is a form of psychotherapy. It is not a medication and not a substance, but a procedure that takes place in conversations and exercises.

The approach does not target the symptom itself, but the relationship to one’s own thoughts and feelings. Distressing thoughts, feelings and bodily sensations are not to be fought. Instead, they are noticed and carried along. At the same time, attention is paid to one’s own values and to the steps that fit them. There is a technical term for this interplay: psychological flexibility. It refers to the ability to deal with unpleasant inner states in such a way that one can do what matters to oneself.

How the procedure is carried out is not rigidly prescribed. Sessions are described both individually and in groups, guided self-help programmes on the internet, video sessions, short learning units for in between and combinations with movement programmes. Some programmes run in pain clinics, others are aimed at adolescents and their parents. ACT is therefore less a fixed protocol than a family of applications with a common goal.

2. What Studies Show

ACT is best studied in chronic pain. There are review articles that summarise many individual studies.

One such 2023 review pooled 21 randomised controlled trials with 1962 participants 1. Randomised controlled means the participants were assigned to a group by chance and there was a comparison group. In this summary, participants showed better pain acceptance, better quality of life and better pain-related functioning. Pain intensity, anxiety and depressive symptoms decreased.

A second review from the same year summarised 33 studies with 2293 participants 2. It reported small to moderate improvements in pain intensity and physical function. When ACT was delivered in person, improvements in physical endpoints were greater than when delivered via the internet. People with chronic headache and with fibromyalgia benefited more than people with non-specific pain.

A further 2022 review of 25 randomised controlled trials found improvements in pain interference, disability, depression and quality of life 5. Pain interference refers to how much pain disrupts daily life.

Individual studies are also informative. In 101 people with lung cancer, a seven-week internet-based ACT was compared with usual care 7. Participants in the ACT group reported better quality of life, greater psychological flexibility and less anxiety. In a feasibility study with 63 people with complex chronic pain, 56 per cent of the online ACT group rated their condition as markedly improved, compared with 20 per cent in the control group 6. A feasibility study primarily checks whether a programme is practicable, not whether it works.

Comparisons have also been made as to whether ACT requires attendance at a practice. In a study with 128 veterans with chronic pain, eight weeks of ACT were delivered by videoconference and in person 4. Both groups improved, except for sleep quality. More participants in the video group discontinued treatment.

3. What Remains Unclear

For areas outside pain and fatigue, individual controlled studies do not yet permit a statement. In cancer, burnout and older people with joint disease there are initial feasibility, pilot and review studies; larger studies with longer follow-up are still pending 78109.

The studies are also difficult to compare. Formats, comparison groups, durations and questionnaires differ substantially. Many results are based on self-reports by participants. A questionnaire score is a marker, not a disease course.

The frequently cited 2017 telehealth study was designed as a non-inferiority trial. Such a design is intended to show that two approaches are similarly effective. By its construction it cannot demonstrate that one is superior.

It also remains open which patient groups benefit most from which format and duration.

4. What This Means in Practice

Anyone reading the research on ACT encounters many studies that primarily examine how the procedure is offered: as a guided internet programme, by video, as a short learning unit or in combination with movement. These questions are legitimate, because access partly determines who reaches an offer at all. They answer a different question, however, from the one about efficacy.

In addition, in some studies more than one thing is changed, for example ACT together with a movement programme. From such combinations it is not possible to deduce what ACT alone achieves.

The strongest statements come from reviews on chronic pain. There a pattern emerges: improvements are usually more pronounced at the end of treatment than at later follow-up.

What would decide the matter is a controlled study that compares ACT with another active treatment and jointly measures psychological flexibility and pain course over a longer period.

All details with study numbers and sources: Detailed Page on Acceptance and Commitment Therapy (ACT). For children: Acceptance and Commitment Therapy (ACT) for Children.