Clinimetric Analysis of Outcome Measures for Airway Clearance in Adults with Cystic Fibrosis: A Systematic Review

Abstract

\n Background Airway clearance techniques (ACTs) are integral to cystic fibrosis (CF) management. However, there is no consensus as to which outcome measures (OMs) are best for assessing ACT efficacy. Objectives: To summarise OMs that have been assessed for their clinimetric properties (including validity, feasibility, reliability & reproducibility) within the context of ACT research. MethodsEligibility Criteria - Any parallel or cross-over randomised controlled trial (RCT) investigating outcome measures for ACT in the CF population. Information sources: Five medical databases; clinicaltrials.gov; abstracts from international CF conferences. Risk of Bias - The authors planned to independently assess study quality and risk of bias using the COSMIN risk of bias checklist with external validity assessment based upon study details (participants and study intervention).Synthesis of Results – Two review authors (GS and MJ) independently screened search results against inclusion criteria, further data extraction was planned but not required.ResultsIncluded studies - No completed RCTs from the 187 studies identified met inclusion criteria for the primary or post-hoc secondary objective. Two ongoing trials were identified.DiscussionLimitations of evidence: The search strategy may have missed some lesser-known terms for ACT or manuscripts reporting clinimetric properties solely within text. Studies validating outcome measures for use in other aspects of CF, which may be relevant to ACT, are not included.Interpretation - High-quality RCTs are urgently needed to investigate & validate the clinimetric properties of OMs used to assess ACT efficacy. With the changing demographics of CF combined with the introduction of CFTR modulator therapies, an accurate assessment of the current benefit of ACT or the effect of ACT withdrawal is a high priority for clinical practice and future research and OMs which have been validated for this purpose are essential.OtherFunding: NIHR/HEE Clinical Doctoral Fellowship grant for GS (reference CDRF-2014-05-055).Systematic review registration number - PROSPERO no.CRD42020206033