Pulmonary Rehabilitation Delivered in Low-Resource Settings for People with Chronic Respiratory Disease: Protocol for a Mixed Methods Process Evaluation of a Three-Arm Randomised Implementation Trial (PuRe)

Background: Over half of the 550 million people with chronic respiratory disease (CRD) live in low- and middle-income countries with limited access to pulmonary rehabilitation (PR) that could improve exercise tolerance and quality of life. The PuRe trial tests effectiveness of Home- and Centre-based PR versus usual care in four centres across India, Bangladesh and Malaysia. This protocol outlines the methods used in the process evaluation of the PuRe trial, focused on understanding the context, implementation and mechanisms of PR. Aim:To understand how PR was delivered in the four centres, how the delivery was influenced by the local and national context and the likely mechanisms of impact of PR on trial outcomes. Methods: We use a mixed-methods design. Quantitative data will be collected from researcher and therapist logs and validated questionnaires; qualitative data from interviews with patients, therapists, healthcare professionals, managers, and policymakers. Approximately 80 patients and 20–32 healthcare/stakeholders will be interviewed, guided by data saturation. Implementation: This is assessed via PR reach, fidelity, dose and adaptation. Sustainability will be explored in stakeholder interviews. Mechanisms: These are assessed by patient engagement with PR, patient and therapist experiences and mediators (smoking, physical activity, breathlessness). Context: This is assessed using the Consolidated Framework for Implementation Research exploring how setting, individuals and implementation processes shape delivery and outcomes. Quantitative and qualitative data will be analysed separately and later combined in a mixed-methods synthesis for the purposes of triangulation and complementarity. Discussion: Alongside the trial evidence on effectiveness, an understanding of when, why and how PR works gained through the process evaluation will be valuable for those implementing similar services in other low-resource settings. Trial registration: ISRCTN 65701828.