Bibliometric and Thematic Review of Research Studies Reporting Swallowing Data across Multiple Consistencies (2012–2024)

In 2015, the International Dysphagia Diet Standardisation Initiative (IDDSI) published a systematic review of evidence describing the impact of liquid consistency and food texture on swallowing [1, 2]. A recent update synthesized new evidence published since 2012 [3]. As part of full-text review, bibliometric and thematic analysis was completed for 465 articles, which met inclusion criteria of reporting quantitative measures of swallowing in humans across at least two consistencies, with a sample size ≥ 10 participants. Study characteristics were extracted using the universal applicable questions domain of the Framework for RigOr aNd Transparency In REseaRch on Swallowing (FRONTIERS; https://www.frontiersframework.com ), a critical appraisal tool for evaluating study quality and reporting in dysphagia research. Appraisals were performed independently by two reviewers. Data cleaning and discrepancy resolution were performed by the two lead authors. Thematic analysis identified patterns related to study characteristics, scientific rigor and reporting transparency. Parameters were considered well-reported if present in ≥ 60% of the articles, and poorly-reported when present in ≤ 25%. The included articles originated in 32 different countries around the world: 27% coming from Canada/USA, 23% from Europe, 27% from Asia, and 22% from Latin America, Oceania, and Africa/Middle East. With respect to study populations, 425 (91%) reported data for adult participants and 53 (11%) for pediatric participants, with 137 studies (29%) focusing on healthy swallowing. Critical appraisal highlighted gaps with respect to representation of diverse racial and ethnic groups, and a need for greater clarity in reporting the criteria used to define and measure dysphagia severity in future studies.