2.3 Exclusion criteria
The exclusion criteria include any of the following: (a) Non-English
language studies; (b) Full-text literature that cannot be obtained
through various channels; (c) Participants with pulmonary disease other
than asthma; (d) Conferences, guidelines, reviews, animal experiments;
(e) Non-randomized controlled trials with study designs that were,
retrospective, observational, cohort, and case-control studies.