Background: Scoping reviews are used to map concepts underpinning a research area and the main sources and types of evidence available. Currently, a lack of consistency exists in the terminology, definition, methods, and reporting of scoping reviews appearing in the literature.
Objectives: We aimed to synthesize scoping review approaches through a scoping review.
Methods: We conducted a scoping review of scoping reviews. Nine multi-disciplinary electronic databases were searched for scoping reviews or studies that discussed scoping review methodology (e.g. the Cochrane Library, PsycINFO, Philosopher’s Index). The citations were screened independently by two reviewers for inclusion, and data extraction was verified by a second reviewer. Descriptive analysis was conducted.
Results: We included 545 scoping review articles. Preliminary results suggest that there has been an exponential increase in the number of scoping reviews conducted in the past five years. The majority were conducted in North America (56%) and Europe (39%). Most studies reported a source of funding (61%) that was either from the government (25%) or a health authority (16%). The most commonly reported approaches to the conduct of scoping reviews included searching one or more database (92%), scanning reference lists (59%), searching grey literature (52%), limiting inclusion by date (68%) or language (62%), and not conducting a formal quality (risk of bias) appraisal (81%). In most cases, the results of the scoping review were used to provide recommendations for future research (78%), identify evidence gaps (76%), and/or to specify policy or practice recommendations (54%).
Conclusions: The number of scoping reviews conducted per year is increasing exponentially. Scoping reviews are used to set research agendas and provide policy or practice recommendations, yet there is variability in their reporting and the methods that are being used. Further research on scoping reviews is warranted, in particular, there is need for a guideline to standardize reporting.