Patient-friendly summary
If you read nothing else
Bottom line
ACT shows promise for improving quality of life, pain acceptance and related symptoms in fibromyalgia and appears well tolerated, but the small, varied evidence base means larger trials are needed to confirm how big the benefit really is.
Preliminary evidencePublished
Evidence hierarchy
Study participants
Adults with fibromyalgia (ACR criteria or self-report) in Europe and North America
Study Summary
This systematic review and meta-analysis pooled six randomised controlled trials (384 mostly-female participants) to evaluate acceptance and commitment therapy (ACT) for fibromyalgia. ACT, delivered online, in groups or one-to-one, was superior to control conditions for improving health-related quality of life (FIQ) and pain acceptance (CPAQ) both immediately after treatment and at follow-up, and showed moderate-to-large improvements across secondary outcomes including pain, disability, depression, anxiety and fatigue. Attrition stayed below 20% in four of six studies and no adverse events were attributed to ACT. The authors emphasise that the evidence base is small, methodologically varied and at risk of overestimating effect sizes, so larger trials are needed before firm conclusions can be drawn.
Key Findings
| Finding | Detail | Impact |
|---|---|---|
| ACT improved fibromyalgia-related quality of life (FIQ) versus controls | Pooled effect favoured ACT at post-intervention (SMD -1.05, 95% CI -2.02 to -0.09) and at follow-up (SMD -1.43, 95% CI -2.17 to -0.69), with negative scores indicating reduced disease impact. FIQ was reported by only four of six studies. | High |
| ACT increased pain acceptance (CPAQ) versus controls | Pooled effect favoured ACT post-intervention (SMD 1.05, 95% CI 0.61 to 1.49) and at follow-up (SMD 0.95, 95% CI 0.40 to 1.49). CPAQ/CPAQ-R was reported by only four of six studies. | High |
| Secondary outcomes showed moderate-to-large improvements post-intervention | Large pooled effects for depression and anxiety and moderate effects for pain and disability post-intervention, all with confidence intervals excluding zero. Fatigue (reported by a single study) improved with a large effect (SMD -0.94, 95% CI -1.67 to -0.22). | Medium |
| Some benefits were less certain at follow-up | For pain intensity at follow-up the pooled SMD was -0.48 but the 95% CI crossed zero, so the effect was not statistically meaningful; for disability at follow-up the upper CI was near zero (-0.01). | Medium |
| Acceptability and safety appeared favourable | Attrition was between 5 and 10% in five studies; one study exceeded 20% overall (27.3%), driven by control-group dropout (40.0%) rather than the ACT arm (16.7%). No adverse events were reported as attributable to ACT. | Medium |
| In one trial ACT outperformed recommended pharmacological treatment | Group ACT versus recommended pharmacological treatment (pregabalin +/- duloxetine) favoured ACT for FIQ (SMD -1.80, 95% CI -2.26 to -1.34 post-treatment) and CPAQ (SMD 1.35, 95% CI 0.92 to 1.78 post-treatment); this is a single-study finding. | Medium |
Pooled effect favoured ACT at post-intervention (SMD -1.05, 95% CI -2.02 to -0.09) and at follow-up (SMD -1.43, 95% CI -2.17 to -0.69), with negative scores indicating reduced disease impact. FIQ was reported by only four of six studies.
Pooled effect favoured ACT post-intervention (SMD 1.05, 95% CI 0.61 to 1.49) and at follow-up (SMD 0.95, 95% CI 0.40 to 1.49). CPAQ/CPAQ-R was reported by only four of six studies.
Large pooled effects for depression and anxiety and moderate effects for pain and disability post-intervention, all with confidence intervals excluding zero. Fatigue (reported by a single study) improved with a large effect (SMD -0.94, 95% CI -1.67 to -0.22).
For pain intensity at follow-up the pooled SMD was -0.48 but the 95% CI crossed zero, so the effect was not statistically meaningful; for disability at follow-up the upper CI was near zero (-0.01).
Attrition was between 5 and 10% in five studies; one study exceeded 20% overall (27.3%), driven by control-group dropout (40.0%) rather than the ACT arm (16.7%). No adverse events were reported as attributable to ACT.
Group ACT versus recommended pharmacological treatment (pregabalin +/- duloxetine) favoured ACT for FIQ (SMD -1.80, 95% CI -2.26 to -1.34 post-treatment) and CPAQ (SMD 1.35, 95% CI 0.92 to 1.78 post-treatment); this is a single-study finding.
Strengths
- Followed PRISMA guidance and assessed risk of bias with the Cochrane Handbook; all six included studies were rated high quality (0-2 unclear/high risks of bias).
- Included trials had high treatment quality on the Yates rating scale (five scored 8/9, one 7/9).
- Authors of included studies were contacted to obtain unpublished or fibromyalgia-specific data, reducing reporting gaps.
- Funnel plots for the two primary outcomes did not indicate a high risk of publication bias.
- Spanned multiple delivery modes (online, group, one-to-one) and several countries, supporting generalisability to European and North American clinical practice.
Limitations
- Only six RCTs were available, with differing methodologies, sample sizes and outcome measures.
- Three studies had fewer than 50 fibromyalgia participants and three were statistically underpowered, so effect sizes may be overestimated (upward bias) despite Hedge's g correction.
- The two primary outcomes (FIQ and CPAQ) were each reported by only four of the six studies.
- Heterogeneity was high for several outcomes (I-squared ranged 0-92%) and could not be explored via subgroup analysis or meta-regression due to too few studies.
- At follow-up, the pooled effect for pain intensity was not statistically meaningful (95% CI crossed zero), and disability effects were close to zero.
- Results may not be applicable outside Europe and North America; one study had a notable conflict of interest (authors affiliated with the app developer that funded it).
- The protocol was specified in advance but not registered.
Key Takeaways for Patients
What This Means for You
- 01Acceptance and commitment therapy (ACT) is a talking therapy that aims to build psychological flexibility - learning to accept difficult thoughts and feelings while staying focused on what matters to you - rather than trying to eliminate pain.
- 02Across six small trials, ACT was linked to better quality of life and greater pain acceptance in people with fibromyalgia, with improvements often holding up at follow-up.
- 03ACT was also associated with improvements in pain, disability, depression, anxiety and fatigue, though the certainty for pain at longer follow-up was weaker.
- 04ACT can be delivered in different ways - online, in a group, or one-to-one - which may help people who face cost or travel barriers to in-person therapy.
- 05No harms were reported from ACT, but because the studies were few and small, the true size of the benefit is uncertain and larger studies are needed.
Read the Full Paper
Access the complete peer-reviewed study from British Journal of Pain
View Full Study