Core Outcome Set for Studies Investigating Secretion Clearance Interventions Used in the Community by Patients With Neuromuscular Disease

<b>Background:</b> Several treatments are used in the community to improve secretion clearance for patients with neuromuscular disease (NMD). However, the optimal intervention remains unclear with further research required. We aimed to develop a core outcome set (COS) for studies investigating secretion clearance interventions used in the community by patients with NMD. <b>Methods:</b> We conducted a scoping review, qualitative interviews with patients/family, modified e-Delphi survey, and consensus meeting. We recruited health care professionals, patients, and caregivers. Delphi participants were provided a 9-point Likert scale to score outcomes as "not important" (1- 3), "important but not critical" (4-6), or "critical" (7-9). Those scored as critical for inclusion were discussed at the consensus meeting using nominal group technique methods to achieve final consensus. <b>Results:</b> Ninety participants were recruited for the e-Delphi. Twenty-nine outcomes identified from the scoping review and qualitative interviews were taken forward to Round 1. Eleven additional outcomes were suggested by participants during Round 1. Forty outcomes were presented in Round 2. Sixteen outcomes were voted as critical for inclusion and taken forward to the consensus meeting (20 participants). The final COS includes measured cough strength/power, burden of respiratory illness, patient-reported effectiveness of secretion clearance, patient-reported experience of airway clearance, quality of life, adherence to secretion clearance intervention, and adverse events related to secretion clearance intervention. <b>Conclusions:</b> This COS should now be included in all trials investigating secretion clearance interventions in the community for patients with NMD. Next steps are to identify measurement tools and characteristics such as measurement time points for these outcomes using COSMIN methodology.