World Workshop on Oral Medicine VIII: Development of a core outcome set for dry mouth: a systematic review of outcome domains for xerostomia.

OBJECTIVE: The purpose of this study was to identify all outcome domains used in clinical studies of xerostomia, that is, subjective sensation of dry mouth. This study is part of the extended project "World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research" to develop a core outcome set for dry mouth. STUDY DESIGN: A systematic review was performed on MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials databases. All clinical and observational studies that assessed xerostomia in human participants from 2001 to 2021 were included. Information on outcome domains was extracted and mapped to the Core Outcome Measures in Effectiveness Trials taxonomy. Corresponding outcome measures were summarized. RESULTS: From a total of 34,922 records retrieved, 688 articles involving 122,151 persons with xerostomia were included. There were 16 unique outcome domains and 166 outcome measures extracted. None of these domains or measures were consistently used across all the studies. The severity of xerostomia and physical functioning were the 2 most frequently assessed domains. CONCLUSION: There is considerable heterogeneity in outcome domains and measures reported in clinical studies of xerostomia. This highlights the need for harmonization of dry mouth assessment to enhance comparability across studies and facilitate the synthesis of robust evidence for managing patients with xerostomia.

World Workshop on Oral Medicine VIII: Development of a core outcome set for dry mouth: the patient perspective.

OBJECTIVE: We conducted a qualitative study of patients' perspectives on dry mouth outcomes to explore their personal experiences and investigate which outcomes are most important to them. This work was part of the WONDER initiative (World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research) exploring Core Outcome Measures in Effectiveness Trials. STUDY DESIGN: Using a study-specific topic guide, we conducted digitally recorded, semi-structured interviews of focus groups of patients with dry mouth secondary to Sjögren syndrome and head and neck radiotherapy. We conducted interviews until data saturation had been achieved and evaluated all transcripts for accuracy before we anonymized the data. RESULTS: Two focus groups consisting of 4 participants per group identified 4 distinct themes: (1) impact on oral health and function, (2) social isolation and withdrawal, (3) frustration with dry mouth management, and (4) limited knowledge of the medical community and lack of understanding of family and friends. CONCLUSIONS: The diversity of self-reported outcomes and the complexity of patient perceptions identified in our work may represent additional barriers to successful dry mouth management that should be considered in the design of future clinical trials.