P048 Polysomnographic titration of non-invasive ventilation in motor neurone disease (3TLA): Protocol for a process evaluation of a clinical trial

INTRODUCTION: We are undertaking a multicentre randomised controlled trial to determine the effectiveness of including a sleep study (polysomnography, PSG) to assist the commencement of non-invasive ventilation (NIV) in people with motor neurone disease (MND); the PSG4NIVinMND trial. A process evaluation will be conducted alongside the clinical trial. The aim of the process evaluation is to understand: 1) the implementation of the PSG4NIVinMND intervention in the seven trial sites, including the barriers and enablers; and 2) the causal mechanisms through which the PSG4NIVinMND intervention produces change. METHODS: The process evaluation has a mixed-methods design, comprising qualitative and quantitative components, and is guided by two theoretical frameworks: RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance) and the Theoretical Domains Framework (TDF). Qualitative data include semi-structured interviews with clinical trial participants (people with MND) and their carers, and focus groups and surveys with health professionals involved in delivering the intervention. Quantitative process data will also be collected from the clinical trial. Data will be analysed iteratively throughout the trial. RESULTS: Six of the seven sites have commenced recruitment to the PSG4NIVinMND trial. Baseline focus groups and surveys have been completed with health professionals from these sites. Data collection and analysis will continue until the PSG4NIVinMND trial has concluded. CONCLUSION: This process evaluation will provide valuable insights into how the PSG4NIVinMND intervention was implemented in the trial sites, for whom and how the PSG4NIVinMND intervention was (and was not) effective, and how it could be implemented into routine clinical practice.