Understanding the processes underpinning IMPlementing IMProved Asthma self-management as RouTine (IMP²ART) in primary care: study protocol for a process evaluation within a cluster randomised controlled implementation trial

Background: Providing supported self-management for people with asthma can reduce the burden on patients, health services and wider society. Implementation, however, remains poor in routine clinical practice. IMPlementing IMProved Asthma self-management as RouTine (IMP²ART) is a UK-wide cluster randomised implementation trial that aims to test the impact of a whole-systems implementation strategy, embedding supported asthma self-management in primary care compared with usual care. To maximise opportunities for sustainable implementation beyond the trial, it is necessary to understand how and why the IMP²ART trial achieved its clinical and implementation outcomes.

Methods: A mixed-methods process evaluation nested within the IMP²ART trial will be undertaken to understand how supported self-management was implemented (or not) by primary care practices, to aid interpretation of trial findings and to inform scaling up and sustainability. Data and analysis strategies have been informed by mid-range and programme-level theory. Quantitative data will be collected across all practices to describe practice context, IMP²ART delivery (including fidelity and adaption) and practice response. Case studies undertaken in three to six sites, supplemented by additional interviews with practice staff and stakeholders, will be undertaken to gain an in-depth understanding of the interaction of practice context, delivery, and response. Synthesis, informed by theory, will combine analyses of both qualitative and quantitative data. Finally, implications for the scale up of asthma self-management implementation strategies to other practices in the UK will be explored through workshops with stakeholders.

Discussion: This mixed-methods, theoretically informed, process evaluation seeks to provide insights into the delivery and response to a whole-systems approach to the implementation of supported self-management in asthma care in primary care. It is underway at a time of significant change in primary care in the UK. The methods have, therefore, been developed to be adaptable to this changing context and to capture the impact of these changes on the delivery and response to research and implementation processes.