Psychometric properties of patient-reported outcome measures for dysphagia in head and neck cancer: a systematic review protocol using COSMIN methodology

Abstract Background Dysphagia (swallowing difficulty) is one of the most common and debilitating sequelae of head and neck cancer (HNC). Patient-reported outcome measures (PROMs) are a fundamental component of dysphagia outcomes evaluation, as they inform treatment consequences that cannot be captured by objective clinician measures. Many PROMs for dysphagia in HNC are available, but their validity is unclear. As a consequence, the selection of the most appropriate PROM for dysphagia in HNC is complex and often based on the clinician’s personal preferences, rather than on valid psychometric properties. This protocol describes a systematic review aiming at (1) identifying PROMs specific to dysphagia symptoms, swallowing functional status, swallowing-related health status, and swallowing-related quality of life in HNC, (2) mapping them to our conceptual framework of dysphagia-related PROs, and (3) appraising their psychometric properties using the Consensus Based Standards for the Selection of Health Measurement Instrument (COSMIN) methodology. Methods Six electronic databases will be searched from inception to December 2020 for all primary studies in any language and design detailing PROM development, reliability, validity, feasibility, interpretability, and/or cross-cultural adaptation. Eligibility criteria will target PROMs for patients with HNC (≥ 90% of the study sample) with ≥ 20% of their items pertaining to swallowing. Two independent raters will screen abstract and full texts and a third rater will resolve discrepancies. Data will be extracted on study, sample and PROM characteristics, and results of psychometric testing. PROMs will be mapped to our conceptual framework. The methodological quality of included PROMs and their psychometric properties will be appraised using the COSMIN risk of bias checklist and evidence will be summarized using a modified Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Discussion This systematic review will provide a summary of existing dysphagia-related PROMs for people with HNC and a comprehensive account of their psychometric properties. We will provide recommendations on PROMs selection which will aid healthcare professionals to the most appropriate PROM based on its validity, reliability, feasibility, interpretability and suitability for clinical and research settings. Further recommendations will be made on areas of measurement property requiring further testing. Systematic review registration PROSPERO registration ID: CRD42021237877