Reduce and recycle: Examining relevant, existing synthesised evidence to avoid research waste and refine the preparation of new systematic reviews




Poster session 2 Thursday: Evidence synthesis - methods / improving conduct and reporting


Thursday 14 September 2017 - 12:30 to 14:00


All authors in correct order:

Naude C1, Nicol L1, Young T1
1 Centre for Evidence-based Health Care, Stellenbosch University, South Africa
Presenting author and contact person

Presenting author:

Celeste Naude

Contact person:

Abstract text
Background: Between 2010 and 2014 the number of systematic reviews (SRs) and meta-analyses indexed by PubMed increased by 67% and 132%, respectively, compared to 27% for all indexed items. To avoid duplication and support the production of good-quality, useful SRs, it is important to critically examine existing, relevant synthesised research prior to starting a new SR.

Objective: To describe our unit’s approach to critically examining existing, relevant SRs to reduce research waste in order to refine and enhance the preparation of new SRs.

Methods: We purposively selected 8 projects from our unit over the past 5 years for which critical examinations of existing SRs were done. Through a consultation process and drawing on our shared experiences, we documented common approaches used, as well as the main learning points.

Results: All critical examinations started with a research question for a possible new SR that informed the development of a succinct protocol including PICOTS elements, well-defined objectives, a search strategy and methods for data extraction and management. All the critical examinations searched for existing, relevant SRs in at least 2 electronic databases, including databases with primary and secondary studies, such as PubMed and databases of systematic reviews only, such as Epistemonikos. Using an iterative process the question was refined or redefined, depending on the availability and scope of existing, relevant SRs. The search date and methodological quality of existing SRs were also considered in the decision-making process for each critical examination. An algorithm was developed to consolidate the common approaches that direct the course of the critical examination process.

Conclusion: To map and examine the scope of existing, relevant systematic reviews before starting a new review is a necessary and valuable step before starting a new SR. This process reduces research waste, identifies and clarifies research gaps and refines or redefines the SR question, all of which streamlines the preparation of new SRs.