Swallowing Outcome Measures in Dysphagia Interventions in Parkinson s Disease: Protocol for a Scoping Review

Abstract

Background: Combining trial results to direct people with oropharyngeal dysphagia (OD) in Parkinson’s disease (PD) for treatment is difficult because of the high variability of how outcomes are being defined and measured, missing information on adverse events and possible outcome-reporting bias. Therefore, as a first step on the establishment of a Core Outcome Set for Dysphagia Interventions in Parkinson's Disease (COS-DIP) a scoping review will be conducted to systematically map the research done in this area and to identify any existing gaps in knowledge. Objective: This scoping review aims to report on swallowing outcomes, their assessments and applied timepoints in (quasi-) Randomised Controlled Trials (RCTs) and Controlled Clinical Trials (CCT) in people with OD in PD and ultimately develop a COS-DIP. Methods: All clinical interventions with a (quasi-) RCT and CCT design for people of 18 years or older with OD in PD will be included. Key electronic databases and trial registries without any date or language restrictions will be searched. Two independent reviewers will assess articles for eligibility. The outcome measures applied in the included studies will be extracted following the taxonomy by Dodd et al. (2018). Additionally, information on the chosen verbatim and definition of the outcome, the applied assessments, frequency and timepoints of measurement will be charted. Conclusions: This scoping review will inform the establishment of the COS-DIP as a first step. Ultimately this has immense potential to change how trials are conducted for OD in PD worldwide as it will translate to higher quality meaningful trials and increase consistency among trials.