Objective: The objective of this study was to investigate the impact of the peer review of literature search strategies prepared in support of rapid reviews. Methods: A sample of 200 CADTH rapid reviews was selected. For each rapid review meeting the inclusion criteria, the pre-peer-reviewed and corresponding post-peer-reviewed search strategies were run, and the search results were compared. Bibliographic records retrieved solely by the post--peer-reviewed search strategy and included in the rapid review report were identified as representing "included studies." The publication type of each included study was determined, and the attributes of the corresponding record were analyzed to determine the reason for its retrieval by the post--peer-reviewed search. Results: The peer review of search strategies resulted in the retrieval of one or more additional records for 75% of the searches investigated, but only a small proportion of these records (4%) represented included studies. The main publication types of the included studies were nonrandomized studies (60%) and narrative reviews (20%). The principal changes to search strategies that resulted in the retrieval of additional included studies were the inclusion of more keywords or subject headings or a change in the way concepts were combined. Conclusions: The peer review of literature search strategies aids in the retrieval of relevant records particularly those representing nonrandomized studies. The scrutiny of keywords, subject headings, and the relation between search concepts are key components of the peer review process.