Education and learning: potential methodological and ethical issues in systematic reviews containing a meta-analysis:...

Junior doctors make clinical decisions regularly; therefore, they need to adequately interpret the evidence supporting these decisions. Patients can be harmed if clinical treatments are supported by biased or unreliable evidence. Systematic reviews that contain meta-analyses of randomized controlled trials are a relatively low-biased type of evidence to support clinical interventions. Therefore, it is reasonable to think that doctors will likely select this type of study to answer clinical questions. In this article, doctors are informed about potential methodological and ethical issues in systematic reviews that contain a meta-analysis that are sometimes not easily identified or even overlooked by the current tools developed to assess their methodological quality or risk of bias. The article presents a discussion of topics related to data extraction, accuracy in reporting, reproducibility, heterogeneity, quality assessment of primary studies included in the systematic review, sponsorship, and conflict of interest. It is expected that the information reported will be useful for junior doctors when they are reading and interpreting evidence from systematic reviews containing meta-analyses of therapeutic interventions, mainly those doctors unfamiliar with methodological principles.