Background: Citation searching is a valuable form of supplementary searching for scoping reviews, but is often time consuming. Several citation indexes and tools are now available to make this process more efficient, but it is unclear which may provide the best return on investment. Past studies have investigated the value of citation indexes in the context of systematic reviews or the coverage provided. However, these studies are limited in value as they do not include a robust grey literature search, do not include citation searching tools (e.g. CitationChaser), or do not quantify the value of the indexes with the number of relevant studies identified.

Objective: To test citation searching indexes/tools in the context of a scoping review that includes grey literature to quantify value of each index/tool.

Methods: A literature search was conducted to find citation searching indexes/tools that allow for bulk download of references. All citation indexes/tools were used for backward and forward citation searching in the scoping review. Recorded for each tool was: time needed to complete citation searching, total number of references retrieved and number of relevant references retrieved. Sensitivity and precision of backward and forward citation searching will be calculated for each tool using any relevant citations identified through citation searching as a reference set.

Results: Descriptive statistics for each tool will be shared along with recommendations for which tool(s) may provide the best balance of time spent and relevant references found.