The review question was clearly stated. Three relevant databases were searched. Limited efforts were made to search for unpublished studies, so some relevant studies may have been missed. Steps were taken to minimise reviewer error and bias in study quality assessment, but not explicitly with study selection and data extraction.
Trial quality was assessed and results reported. The methods used to combine data and account for statistical heterogeneity were appropriate and justified. Limited details about included trials were reported. Few trials with large sample sizes were included. No evidence was provided for inferences on costs and cost-effectiveness of treatments.
Given a number of weaknesses (potential for publication bias, high risk of reviewer error and bias, incomplete reporting of trial details) the reliability of the authors' conclusion is uncertain.