3.1 Data search results
The search flow results of our systematic review are described in the
study selection process (Appendix S1). After removing 20 duplicate
records, the titles and abstracts of 57 records were screened. We
excluded 48 records by reading the abstracts, of which 16 studies
included only one treatment group without a comparison group and 32
studies were reviews, commentaries and case reports. Of the 9 full-text
articles assessed for eligibility, 2 were excluded for reporting
overlapping data. Finally, 7 studies met the selection criteria and were
included in the meta-analysis [12-14,21-24].