Weaving common threads in environmental causal assessment methods: toward an ideal method for rapid evidence synthesis

Accurate and informative methods for evidence synthesis that are also simple and inexpensive to implement would greatly increase our ability to use scientific research results to better manage natural environments. Across the world, pressure to use evidence-based environmental management is increasing, but little guidance exists as to what ‘evidence-based’ actually means. Methods for systematic review of literature evidence have been modified from those used in medical research, but the effort involved in using these methods means that they have not been widely adopted. We compared 3 independently developed approaches to ‘rapid evidence synthesis’ methods developed in an attempt to improve efficiency and responsiveness compared to standard methods for systematic review. Each method has features that should be included in an ideal rapid evidence-synthesis method and has potential for further development. Increasing standardization of methods for evidence extraction, quality assessment, and synthesis increases the transparency and repeatability of the results obtained. However, the most important consideration is that the methods are fit for purpose; i.e., that each method is good enough to do the job required. The methods presented in this BRIDGES cluster, and potentially a combined method derived from them, could reduce the effort and cost of evidence synthesis to the scales required for management decisions.