Quality assessment
Since 6 out of 8 included studies were nonrandomized trials without
control groups, the Methodological Index for Nonrandomized Studies
(MINORS) tool was used to assess the article quality. The 8
methodological items in MINORS are as follows: include a clearly stated
aim, inclusion of consecutive patients, prospective collection of data,
endpoints appropriate to the aim of the study, unbiased assessment of
the study endpoint, follow-up period appropriate to the aim of the
study, loss to follow up less than 5% and prospective calculation of
the study size. Every item can be scored as 0 (not reported), 1
(reported but inadequately), or 2 (reported
adequately)28.
In addition, the quality of the 2 included randomized controlled trials
(RCTs) was assessed using the Cochrane Risk of Bias Tool (RoB2), which
evaluates the following aspects: randomization process, deviations from
intended interventions, missing outcome data, measurement of the outcome
and selection of the reported results. Each domain of RoB2 is rated as
“low risk of bias”, “some concerns”, or “high risk of
bias”29.