Process evaluation of a cluster randomised implementation trial examining strategies to increase early access to exercise for people with knee osteoarthritis: protocol.

Introduction: First steps for knee osteoarthritis (OA) is a cluster randomised implementation trial examining the effect of an educational reminder message included in knee X-ray reports on the proportion of people subsequently referred to exercise professionals for their knee OA. Evaluating the processes supporting the completion of the study and the efficacy of the reminder message is essential to interpreting the outcomes of the study and aiding translation into practice.

Methods And Analysis: We will conduct a concurrent process evaluation throughout the current study using a previously published framework for examining cluster randomised trials. This framework divides processes into those occurring at the cluster level and those at the target population level. For the current study, the cluster level is within radiology clinics. The target population is people with newly diagnosed radiologically evident, structural knee OA. A mixed methods design, incorporating survey data, administrative records, field notes and semi-structured interviews with representatives from radiology clinics and people with knee OA, will evaluate these processes. The focus of the evaluation will be recruitment and response processes of the radiology clinics and delivery and response processes for the people with knee OA. We will also describe the context and explore how the nudge theory of behavioural change influences the outcome of the study.

Ethics And Dissemination: The study protocol, inclusive of the process evaluation, was approved by Macquarie University Human Research Ethics Committee (#520221190343842). Findings will be disseminated through national and international conferences, national industry stakeholders and patient advocacy groups to reach all levels of healthcare. Staff at radiology clinics and people with knee OA involved in interviews provide written, informed consent to participate in the process evaluation. Specific findings will be incorporated into training modules aimed at radiology clinics and will be developed by our industry partners.

Trial Registration: Prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622001414707p). Registration occurred in December 2022.