Combining abbreviated literature searches with single-reviewer screening: three case studies of rapid reviews

Background: Decision-makers increasingly request rapid answers to clinical or public health questions. To save time, personnel, and financial resources, rapid reviews streamline the methodological steps of the systematic review process. We aimed to explore the validity of a rapid review approach that combines a substantially abbreviated literature search with a single-reviewer screening of abstracts and full texts using three case studies. Methods: We used a convenience sample of three ongoing Cochrane reviews as reference standards. Two reviews addressed oncological topics and one addressed a public health topic. For each of the three topics, three reviewers screened the literature independently. Our primary outcome was the change in conclusions between the rapid reviews and the respective Cochrane reviews. In case the rapid approach missed studies, we recalculated the meta-analyses for the main outcomes and asked Cochrane review authors if the new body of evidence would change their original conclusion compared with the reference standards. Additionally, we assessed the sensitivity of the rapid review approach compared with the results of the original Cochrane reviews. Results: For the two oncological topics (case studies 1 and 2), the three rapid reviews each yielded the same conclusions as the Cochrane reviews. However, the authors would have had less certainty about their conclusion in case study 2. For case study 3, the public health topic, only one of the three rapid reviews led to the same conclusion as the Cochrane review. The other two rapid reviews provided insufficient information for the authors to draw conclusions. Using the rapid review approach, the sensitivity was 100% (3 of 3) for case study 1. For case study 2, the three rapid reviews identified 40% (4 of 10), 50% (5 of 10), and 60% (6 of 10) of the included studies, respectively; for case study 3, the respective numbers were 38% (8 of 21), 43% (9 of 21), and 48% (10 of 21). Conclusions: Within the limitations of these case studies, a rapid review approach that combines abbreviated literature searches with single-reviewer screening may be feasible for focused clinical questions. For complex public health topics, sensitivity seems to be insufficient.