A systematic review is a comprehensive review of the literature conducted by a research team using systematic and transparent methods in accordance with reporting guidelines to answer a well-defined research question. It aims to identify and synthesize scholarly research published in commercial and/or academic sources as well as in grey (or gray) literature produced by individuals or organizations in order to reduce bias and provide all available evidence for informing practice and policy-making. Systematic reviews may also include a meta-analysis, a more quantitative process of synthesizing and visualizing data retrieved from various studies.