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Clinical and cost-effectiveness of a guided internet-based Acceptance and Commitment Therapy to improve chronic pain–related disability in green professions (PACT-A): study protocol of a pragmatic randomised controlled trial
  1. Yannik Terhorst1,2,
  2. Lina Braun2,
  3. Ingrid Titzler3,4,
  4. Claudia Buntrock3,
  5. Johanna Freund3,
  6. Janika Thielecke3,
  7. David Ebert4,5,
  8. Harald Baumeister2
  1. 1Research Methods, Ulm University, Ulm, Baden-Württemberg, Germany
  2. 2Clinical Psychology and Psychotherapy, Ulm University, Ulm, Baden-Württemberg, Germany
  3. 3Clinical Psychology and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Bayern, Germany
  4. 4GET.ON Institute, Hamburg, Germany
  5. 5Clinical, Neuro- & Developmental Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
  1. Correspondence to Yannik Terhorst; yannik.terhorst{at}


Introduction Chronic pain is highly prevalent, associated with substantial personal and economic burdens, and increased risk for mental disorders. Individuals in green professions (agriculturists, horticulturists, foresters) show increased prevalence of chronic pain and other risk factors for mental disorders. Available healthcare services in rural areas are limited. Acceptance towards face-to-face therapy is low. Internet and mobile-based interventions (IMIs) based on Acceptance and Commitment Therapy (ACT) might be a promising alternative for this population and may enable effective treatment of chronic pain. The present study aims to evaluate the clinical and cost-effectiveness of an ACT-based IMI for chronic pain in green professions in comparison with enhanced treatment as usual (TAU+).

Methods and analysis A two-armed pragmatic randomised controlled trial will be conducted. Two hundred eighty-six participants will be randomised and allocated to either an intervention or TAU+ group. Entrepreneurs in green professions, collaborating spouses, family members and pensioners with chronic pain are eligible for inclusion. The intervention group receives an internet-based intervention based on ACT (7 modules, over 7 weeks) guided by a trained e-coach to support adherence (eg, by positive reinforcement). Primary outcome is pain interference (Multidimensional Pain Interference scale; MPI) at 9 weeks post-randomisation. Secondary outcomes are depression severity (Quick Inventory Depressive Symptomology; QIDS-SR16), incidence of major depressive disorder, quality of life (Assessment of Quality of Life; AQoL-8D) and possible side effects associated with the treatment (Inventory for the Assessment of Negative Effects of Psychotherapy; INEP). Psychological flexibility (Chronic Pain Acceptance Questionnaire, Committed Action Questionnaire, Cognitive Fusion Questionnaire) will be evaluated as a potential mediator of the treatment effect. Furthermore, mediation, moderation and health-economic analyses from a societal perspective will be performed. Outcomes will be measured using online self-report questionnaires at baseline, 9-week, 6-month, 12-month, 24-month and 36-month follow-ups.

Ethics and dissemination This study was approved by the Ethics Committee of the University of Ulm, Germany (file no. 453/17—FSt/Sta; 22 February 2018). Results will be submitted for publication in peer-reviewed journals and presented at conferences.

Trial registration number German Clinical Trial Registration: DRKS00014619. Registered on 16 April 2018.

  • internet- and mobile-based intervention
  • randomised controlled trial
  • green professions
  • prevention
  • chronic pain

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  • Contributors HB and DE obtained funding for this study. HB, DE, IT, LB and YT contributed to the study design. CB contributed to the design of the economic evaluation study. LB and YT are responsible for the recruitment and coordination of the trials. JT and JF supported the recruitment. YT drafted the manuscript. IT was responsible for the development of the suicidal procedure/TAU+ psychoeducation material, and is currently supervising the recruitment process and conduct of the trials as the operational project lead. All authors provided critical revision of the article. All authors approved the final manuscript.

  • Funding The insurance company SVLFG gave a financial contribution the University of Ulm and Friedrich- Alexander University of Erlangen-Nürnberg as expense allowance.

  • Disclaimer The SVLFG had no role in the study design, decision to publish or preparation of this manuscript. The SVLFG will not be involved in data collection, the analyses, decision to publish or the preparation of future papers regarding this study.

  • Competing interests DE reports to have received consultancy fees and served in the scientific advisory board of several companies such as Minddistrict, Lantern, Novartis, Sanofi, Schoen Kliniken and German health insurance companies. He is a stakeholder of the Institute for Online Health Training (GET.ON), which aims to implement scientific findings related to digital health interventions into routine care. HB reports to have received consultancy fees and fees for lectures/workshops from chambers of psychotherapists and training institutes for psychotherapists in the e-mental-health context. IT reports to have received fees for lectures/workshops in the e-mental-health context from educational institutions for psychotherapists. She is implementation lead and project lead for the EU-research project ImpleMentAll at the Institute for Online Health Training (GET.ON). All other authors reported no competing interests.

  • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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