OBJECTIVES : Systematic methodology is the gold standard approach for rigorous literature review that meets specific criteria aimed at identifying and comparing answers to healthcare questions. Systematic reviews to identify clinical and economic evidence are required for many health technology appraisals (HTA). Further, publication of systematic reviews is important in building the evidence base and stakeholder awareness for pharmaceutical products. Nevertheless, there can be inherent flaws associated with systematic reviews, such as limitations in selection of studies and loss of information on important outcomes and patient cohorts/subgroups. The meticulous nature of systematic reviews means they can be time-consuming and resource-intensive. We investigated whether systematic methodology is essential for review publication in high quality journals, or if a non-systematic approach is acceptable for non-HTA evidence generation.

METHODS : The top twenty key journals by impact factor (2016-2018 publications) in the fields of oncology, gastroenterology, and cardiology/cardiovascular medicine were identified through searches of SCImago Journal & Country Rank. All reviews published in these key journals were then identified by searching the Embase bibliographic database using a McMaster University review search filter. Full text papers of the identified reviews were screened and data extracted to identify reviews that had not reported systematic review methodology in their production.

RESULTS : Initial screening of the >350 search results from the top 20 oncology journals revealed that more than 90% of published reviews clearly reported using systematic methodology. Approximately 5% of published non-systematic reviews were expert consensus statements used to develop disease guidelines. The same approach will be applied to the other disease areas to establish any further trends.

CONCLUSIONS : Systematic methodology remains the optimal approach for achieving publication in top journals. However, non-systematic approaches can be considered when supported by a robust expert engagement plan.