Article selection and annotation

Search results from each database were exported, and the title, author(s), journal title or conference name, and publication year were extracted. Duplicate articles were removed. A preliminary screening was conducted to exclude articles failing to meet all inclusion criteria.

Two authors (SB, JH) read the abstracts of all remaining articles, writing a brief summary of each and manually consolidating the summaries into a set of 19 research topics (Table 1).

List of research topics among included articles (n = 122)

SR: speech recognition.

Each article was then annotated by 2 reviewers with its research topic(s), medical domain, and SR system(s) evaluated, if applicable. Articles could be assigned up to 3 research topics. Disagreements between reviewers were resolved through discussion.