R esearch evidence synthesis involves the aggregation of available information using well-defined and transparent methods to search, summarize, and interpret a body of literature, frequently following a systematic review approach. A scoping review is a relatively new approach to evidence synthesis and differs from systematic reviews in its purpose and aims. 1 The purpose of a scoping review is to provide an overview of the available research evidence without producing a summary answer to a discrete research question. 2 Scoping reviews can be useful for answering broad questions, such as "What information has been presented on this topic in the literature?" and for gathering and assessing information prior to conducting a systematic review.Scoping reviews describe existing literature and other sources of information and commonly include findings from a range of different study designs and methods. 5 The broad scope of the collected information makes using formal meta-analytic methods difficult, if not impossible. Results of a scoping review often focus on the range of content identified, and quantitative assessment is often limited to a tally of the number of sources reporting a particular issue or recommendation. In contrast, systematic reviews commonly select the information sources by requiring specific study types, such as randomized controlled trials, and imposing quality standards, such as adequate allocation concealment, and place their emphasis on synthesizing data to address a specific research question. (Table) By focusing on specific studies, the synthesis component in a systematic review often takes the form of a meta-analysis in which the results of multiple scientific studies are combined to develop a summary conclusion, such as a common effect estimate, along with an evaluation of its heterogeneity across studies.A scoping review can be a particularly useful approach when the information on a topic has not been comprehensively reviewed or is complex and diverse. 6 Munn et al. proposed several objectives that can be achieved utilizing the scoping review framework, including identifying types of existing evidence in a given field, clarifying key concepts or definitions in the literature, surveying how research is conducted on a certain topic, identifying key characteristics related to a certain topic, and identifying knowledge gaps.Scoping reviews, like systematic reviews, require comprehensive and structured searches of the literature to maximize the capture of relevant information, provide reproducible results, and decrease potential bias from flawed implementations. The methodological framework for scoping reviews was developed by Arksey and O'Malley 1 and further refined by Levac et al. 7 and the Joanna Briggs Institute. 6,8 Arksey and O'Malley's framework for scoping reviews consists of the following six steps: • Step 1: Identify the research question-the research question should be clearly defined and usually broad in scope to provide extensive coverage. • Step 2: Identify relevant studies-the...