Evaluating cancer research impact: lessons and examples from existing reviews on approaches to research impact assessment.

Impact evaluation can demonstrate if and why conducting cancer research  is worthwhile. Using a mixed methods, multi-category assessment organised within a framework, will provide a robust evaluation, but the ability to perform this type of assessment may be constrained by time and resources. Whichever approach is used, easily measured, but inappropriate metrics should be avoided. Going forward, dissemination of the results of cancer research impact assessments will allow the cancer research community to learn how to conduct these evaluations.