Chapter 6 “Retrieving grey literature, information and data in the digital age”
Here is the new chapter outline and introduction to whet your appetite. This is the penultimate version which has grown to a whopping 60 pages. The bibliography has over 100 references and there are seven tables and two appendices. Comments welcome!
The objective of this chapter is to discuss the retrieval of grey (or gray) literature in support of the research synthesis, and some of the current theories and practices used to perform it systematically. It is assumed that the reader will be familiar with the basics of structured database searching in the social, behavioural or medical sciences and will have read previous chapters in this volume, notably chapter V, entitled Searching bibliographic databases. To get the most from this chapter, the reader should note the descriptions of terms in Table 1 of chapter V, “Key concepts in database searching”.
Grey literature is literature that has not been formally published, has limited distribution or is not available via conventional channels (Auger 1998). Research synthesis is the practice of systematically retrieving, distilling and integrating data from a variety of published sources (“the evidence base”) to draw more reliable conclusions from the literature (Cooper and Hedges 2009). Rothstein and Hopewell have said that “…there is a critical relationship between the reliability and validity of a research synthesis, and the thoroughness of and lack of bias in the search for relevant studies” (2009, 104). In a high quality review that aims to inform policy or practice, the goal is to identify all available evidence, including the grey literature, relevant to the question (Boland, Cherry and Dickson 2013; IOM 2011).
The chapter begins by examining definitions and document types specified as grey literature. The focus is on issues such as thorough search planning, mapping resources to a research question and identifying as many potentially relevant resources for searching as possible. However, the strategies and techniques by which a desired result in grey literature searching is achieved will shift somewhat for each project. In this chapter, several approaches and theories are offered to assist searchers in building their search strategies and refining each to suit an individual purpose and context.
Before any major grey literature searching is undertaken, seeking advice from experts in systematic information retrieval is recommended (Lefebvre C, Manheimer E, Glanville 2011; Boland, Cherry and Dickson 2013). The chapter includes a discussion of the role of grey literature searching in amassing a body of literature for a topic and the importance of peer review of search strategies or checking them with a librarian (McGowan, Sampson, Salzwedel et al 2016). Most of the remainder of the chapter is concerned with extending grey literature search techniques to locate a higher percentage of relevant documents. The chapter concludes with a discussion of when to stop searching and the recording of all searches performed up to that point.