State of the art, state of the science?

A typology of systematic reviews for synthesising evidence on health care

“…The confusion caused by the terms “theory,” “model,” and “framework,” also complicates reviews of theory . Purposefully refining the search can be productive with a reference‐tracking or “snowballing” strategy as evidence emerges, especially when seeking optimal rather than comprehensive yields . This purposeful strategy is suitable for developing or exploring rather than aggregating information from primary studies .…”

“…The search followed the principles of an optimal rather than a formal a priori comprehensive search . It began with the list of references in the paper by Paré et al and progressed iteratively by crosschecking relevant references with Google Scholar supplemented by hand‐searching the reference lists of relevant papers until the yield was saturated and no new information found …”

“…29 It began with the list of references in the paper by Paré et al 16 and progressed iteratively by crosschecking relevant references with Google Scholar supplemented by hand-searching the reference lists of relevant papers until the yield was saturated and no new information found. 25,29,56,64,83 The typology proposed here is focused, like two others, 15,16 on the objectives of the review, such as summarising knowledge with narrative and scoping reviews, aggregating with meta-analysis and qualitative synthesis, and explaining, configuring or synthesising concepts with umbrella and realist reviews. Gough et al 18 suggest more generally a typology of aggregative and configurative reviews, each associated with different search and appraisal methods.…”

“…41 Purposefully refining the search can be productive with a reference-tracking or "snowballing" strategy as evidence emerges, 41,55,59 especially when seeking optimal rather than comprehensive yields. 29,83 This purposeful strategy is suitable for developing or exploring rather than aggregating information from primary studies. 18 Greenhalgh and Peacock, 25 for instance, found that about half the useful evidence from complex reviews of heterogeneous studies emerged from reference-tracking, a third from electronic and hand searches, and a quarter from the personal knowledge or other contacts of the reviewers.…”

Innovation in information retrieval methods for evidence synthesis studies

“…We are grateful to the editorial team of Research Synthesis Methods for encouraging a special issue on this topic. We are delighted too, to welcome a commentary from an expert and leader who has always facilitated and supported the contribution of library and information professionals and who has had a huge and sustained influence in this field for over 20 years …”