Effectiveness and cost-effectiveness of the Pain-at-Work Toolkit for improving work ability in adults with chronic pain: protocol for a cluster randomised controlled trial.

Abstract

Chronic pain affects around 28 million adults in the UK and is associated with impaired work ability, reduced productivity and increased sickness absence. Access to work-focused support within healthcare services is limited, and most employers do not routinely provide structured assistance for employees living with chronic pain. The Pain-at-Work Toolkit is a co‑created, web‑based intervention designed to improve work ability, self‑management, and workplace experiences for employees living with chronic pain. A feasibility trial demonstrated strong acceptability, exceptional recruitment and potential improvements in work ability, providing clear justification for progression to a fully powered evaluation. This paper describes the protocol for a definitive cluster randomised controlled trial to evaluate the effectiveness, cost-effectiveness and implementation of the Pain-at-Work Toolkit. This two-arm, open-label cluster-randomised controlled trial will recruit at least 70 organisations (minimum 35 clusters per arm) and at least 685 participants. Organisations will be randomised 1:1 to (a) support-as-usual (SAU) or (b) SAU plus the Pain-at-Work Toolkit, and Pain-at-Work Manager's Toolkit as an implementation-support component. The primary outcome is work ability at 3 months, measured using the Work Ability Index (three-item version). Secondary outcomes include work self-efficacy, sickness absence, presenteeism, productivity loss, job satisfaction, job stressfulness, turnover intentions, anxiety, depression and health-related quality of life. A mixed-methods process and implementation evaluation will assess fidelity, contextual influences and mechanisms of impact. A health economic evaluation will estimate cost-effectiveness from employer and societal perspectives. Analyses will follow intention-to-treat principles using multilevel modelling. Ethical approval was granted by the University of Nottingham Faculty of Medicine and Health Sciences Research Ethics Committee (Ref: FMHS 1200226) and the UK Health Research Authority and Health and Care Wales (IRAS 367449). Findings will be disseminated through peer-reviewed publications, conference presentations, stakeholder reports and public summaries. NCT07600892.