Deduplication methods for literature citations in systematic evidence reviews: practical insights to guide decision-making

When deciding on an appropriate software and/or methodology for deduplication of retrieved literature citations in systematic evidence synthesis, several factors ought to be considered, including the cost of a deduplication software, familiarity with its use, and the time necessary to conduct deduplication using a particular method. To guide researchers with and without knowledge of systematic evidence synthesis methods in making informed decisions, we sought to compare different commonly used deduplication software/methodologies—Covidence, Rayyan, the Automated Systematic Search Deduplicator, the Systematic Review Accelerator (SRA) Deduplicator, Deduklick, and the Bramer method in Endnote—from the perspectives of an experienced information specialist and a biomedical researcher. We summarized the cost, time, and effort required from each deduplication software/method and reported our findings descriptively. The findings suggest a properly balanced consideration between cost-effectiveness, ease of application of a method, context and researcher’s needs when deciding on deduplication method for systematic evidence synthesis.