5.2.4.1 Finding and using the appropriate resources

A JBI review of textual evidence should consider both published and unpublished material. The aim of the search strategy is to identify all relevant papers suitable for answering the research question posed by the systematic review that are eligible. The literature encompasses several types of published and unpublished material, including articles published in refereed journals and grey literature. Grey literature refers to materials that are unpublished, or have been published by sources that are neither commercial nor academic (e.g. magazine articles, trade press articles, academic dissertation, institutional reports, consultant reports, conference proceedings, fact sheets, websites, policy documents and blogs).  Rather than compete with the published literature, inclusion of grey literature has the potential to complement and communicate findings to a wider audience, as well as to reduce publication bias. It is important that any sources searched should be tailored to the particular review topic.^36,37

In addition to databases of commercially published research and conference proceedings, there are several online sources of grey literature that should be considered alongside hand searching journals, checking reference lists of relevant publications, tracking citations of relevant studies and contacting experts.

As reviews of textual evidence do not draw on published research as the principal designs of interest, the reference is to types of ‘papers’ or ‘publications’ rather than types of ‘studies.’ The timeframe chosen for the search should be justified, and any language restrictions stated and also justified.

Part of the search strategy is to not only define what type of textual evidence is being included (narrative, opinion, policy) but also to provide details if a more specific search is being conducted.  The specificity may include limiting to particular types of evidence (e.g. white papers, policy documents, editorials). This specificity should include a description as to why limiting the search to these forms of evidence is warranted based upon the initial review question(s).

Narrative

Related to accounts of experience from the perspective of patients, health professionals, or other stakeholders in enterprises related to the topic of interest.  Primarily grey literature found in the websites of patient groups, professional associations, or industry/provider groups.

Opinion

Refers to a view or judgement formed about something, not necessarily based on fact on formal empirical evidence; or a statement of advice by an expert on a healthcare matter. Common sources are repositories of learned colleges/bodies and opinion pieces in the professional journals.

Policy

Refers to policy documents or communication artefacts that give direction for action. Relates to policies and the documentation of such things as meetings, discussions, and group communication vehicles such as position papers and newsletters and guidelines or statements of advice by an expert or group of experts or a government department on a healthcare matter. Sources may be websites of government departments, patient groups, professional associations or industry/provider groups.