{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T08:15:43Z","timestamp":1788509743604,"version":"build-2803163510"},"reference-count":70,"publisher":"BMJ","issue":"8","license":[{"start":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T00:00:00Z","timestamp":1785715200000},"content-version":"unspecified","delay-in-days":2,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000380","name":"Guy's and St Thomas\u2019 Charity","doi-asserted-by":"crossref","award":["COV210803"],"award-info":[{"award-number":["COV210803"]}],"id":[{"id":"10.13039\/501100000380","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,7,15]]},"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Post-COVID syndrome (PCS) is an ongoing legacy of the SARS-CoV-2 pandemic. Defined as symptoms persisting beyond 12 weeks following SARS-CoV-2 infection unexplained by an alternative diagnosis, many individuals continue to experience symptoms for months post-infection. Fatigue, breathlessness, cognitive difficulties and sleep disturbances are all commonly reported, frequently impairing daily functioning and quality of life. Acceptance and commitment therapy (ACT), which enhances psychological flexibility and supports values-based behaviour change, has shown effectiveness across long-term health conditions. This protocol describes the evaluation of\n                      <jats:italic>Balance-ACT<\/jats:italic>\n                      as a novel, adapted ACT-based intervention to address the complex physical and psychological needs of people with PCS.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>\n                      A randomised controlled trial (RCT), co-developed with people with PCS, will evaluate the efficacy and cost-effectiveness of Balance-ACT for PCS. A total of 196 adults with PCS will be recruited from specialist long COVID services within secondary care across NHS organisations in England and randomised 1:1 to Balance-ACT or treatment as usual (TAU).\n                      <jats:italic>Balance-ACT<\/jats:italic>\n                      consists of 10 therapist-delivered sessions delivered over 13 weeks. TAU comprises brief educational videos and a self-help leaflet for COVID-19 recovery. Outcomes will be assessed at 7, 14 and 20\u2009weeks post-randomisation. The primary outcome is health-related quality of life, measured using the SF-36 Physical Component Score at 14 weeks post randomisation. Secondary outcomes include physical health-related quality of life at 20 weeks, perceived fatigue, clinical global improvement, sleep disturbance, cognitive functioning, depressive symptoms, anxiety symptoms, post-exertional malaise, breathlessness, muscle strength, muscle fatigue and heart-rate variability. Mediation analyses will examine whether the intervention leads to changes in psychological flexibility, fear-avoidance beliefs, damage beliefs, embarrassment-avoidance, symptom focusing, muscle strength and physical activity and whether these changes are associated with physical health outcomes. We will also conduct a nested qualitative study to explore participants' views of the intervention. Cost-effectiveness will be assessed by comparing health and social care service costs and quality of life outcomes between Balance-ACT and TAU at 20 weeks.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>Ethical approval has been granted by the NHS Camberwell St Giles Research Ethics Committee (reference 23\/LO\/0941). The study results will be disseminated in peer-reviewed journals and presented at international conferences.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT06231238\">NCT06231238<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2026-122602","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T12:05:59Z","timestamp":1785758759000},"page":"e122602","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Randomised controlled trial assessing the efficacy of balance acceptance and commitment therapy (ACT) for post-COVID syndrome: a study 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