A New Process Model of Study Identification Specific to the Identification of Randomised Studies for Systematic Reviews of Medical Interventions

Abstract

Background

Recent work has illustrated that the same process of study identification is used in systematic reviews irrespective of the studies or data needs required for synthesis. We question if different review types should have their own specific models of study identification, to ensure the appropriate and timely identification of studies/study reports and to minimise research waste.

Objective

In this paper, we aim to:

1. illustrate and report a new process model to identify randomised studies for systematic reviews of medical interventions; and

2. situate the model in context of current practice using a worked example from a recent systematic review.

Method

Our model splits the identification of studies from the identification of study reports by searching in distinct phases. It begins with searches of trials registry resources to identify studies, followed by searches of bibliographic databases to identify study reports or unregistered studies. Supplementary search methods are then used to identify unpublished studies. The model includes the possibility of secondary searches, and we consider the role of update searches.

Conclusion

A case study illustrates the application of the method alongside operational guidance.