Search results
A total of 1691 studies found during the initial search, 221 duplicates were removed from. 42 articles remained after analyzing the abstracts and titles of 1470 studies. This meta-analysis includes 11 papers after 31 articles were removed through the full-text review. The search strategy is detailed in S Table1. The flow chart in Figure1 describes the selection procedures for the studies, and the PRISMA checklist is presented in the S Table2. Table 1 shows the characteristics of the included research.
The risk-of-bias assessment is depicted in minute detail in Figure 2. Only four studies showed a low risk of bias [10-13], whereas seven research found an unclear risk of bias[14-20]. Randomization was handled correctly in ten studies[10-19], while allocation-sequence concealment was performed adequately in six studies[10-13, 16, 18]. Information on participants and personnel blinding were provided in six studies[10-13, 15, 16], while eight others reported outcome assessor blinding[10-15, 17, 20]. The cause and number of withdrawals and dropouts were provided for each article.