Data Collection, Risk of Bias Assessment, and Data Analyses
The reviewers independently extracted data from the included studies
using a standardized data collection form based on RevMan v5.3. More
specifically, the following data were extracted: inclusion and exclusion
criteria of the study population, age, sex, recruitment, follow up,
intervention and control, and outcomes of interest. In cases where study
data are deemed unclear or ambiguous, study authors were contacted for
clarifications.
In assessing included studies for bias, the Cochrane Collaboration Tool
Risk of Bias Tool were used to evaluate the following: randomization
method, method of allocation concealment, attrition bias, blinding of
both study subjects and personnel, blinding of outcome assessors,
intention-to-treat analysis, and other biases. The RevMan v5.3 software
was used to analyze the data extracted from the studies. Depending on
the available collective data, prespecified subgroup analyses as stated
in the objectives of the meta-analysis were done. Forest plot analyses
were used to demonstrate the magnitude of treatment effects in terms of
the outcomes of interest. Heterogeneity testing using
I2, Chi-square tests, were also accomplished