Usability and feasibility testing of an enhanced physiotherapist-supported treatment approach integrating a brief behaviour change intervention for people with rotator cuff disorders (The COMBINED approach)

Background People with shoulder pain due to rotator cuff disorder are commonly managed within physiotherapy clinics, yet modifiable lifestyle factors that may contribute to the onset and persistence of pain are not routinely addressed. The COMBINED approach has been developed to integrate brief behaviour change interventions targeting relevant lifestyle factors into routine care. Objectives To undertake sequential usability and feasibility testing of The COMBINED approach prior to evaluation in a randomised controlled trial. Materials and methods A mixed-methods, staged evaluation was conducted. Stage 1 comprised usability testing of the initial prototype, using observations, fidelity assessment, and interviews with physiotherapists and patients. Stage 2 was a pragmatic, multicentre, feasibility study within NHS physiotherapy clinics, assessing intervention fidelity, implementation determinants (TDF-informed survey), patient experience, and recruitment feasibility. Findings The intervention was acceptable and deliverable within routine care. Usability testing with three physiotherapists and six patients identified low initial fidelity and challenges related to ingrained practice behaviours and clinician confidence, informing refinements, including enhanced training and audit and feedback. Feasibility testing involving eight physiotherapists and 17 patients across four NHS trusts demonstrated improved fidelity, particularly in assessment of lifestyle factors and initiating discussions, although complex behaviour change skills remained challenging. Survey findings showed improved implementation following delivery, though prioritisation amid competing demands, habit formation/automaticity and confidence under time pressure remained barriers. Recruitment of patients with relevant lifestyle factors was feasible. Conclusion The COMBINED approach is sufficiently optimised to progress to future trial evaluation, although implementation support will be required to ensure consistent delivery.