Comparative effectiveness and implementation research: directions for neurology.

There is an enormous unmet need for knowledge about how new insights from discovery and translational research can yield measurable, population-level improvements in health and reduction in mortality among those having or at risk for neurological disease. Once several, well-conducted randomized controlled trials establish the efficacy of a given therapy, implementation research can generate new knowledge about barriers to uptake of the therapy into widespread clinical care, and what strategies are effective in overcoming those barriers and in addressing health disparities. Comparative effectiveness research aims to elucidate the relative value (including clinical benefit, clinical harms, and/or costs) of alternative efficacious management approaches to a neurological disorder, generally through direct comparisons, and may include comparisons of methodologies for implementation. Congress has recently appropriated resources and established an institute to prioritize funding for such research. Neurologists and neuroscientists should understand the scope and objectives of comparative effectiveness and implementation research, their range of methodological approaches (formal literature syntheses, randomized trials, observational studies, modeling), and existing research resources (centers for literature synthesis, registries, practice networks) relevant to research for neurological conditions, to close the well-documented evidence-to-practice gap. Future directions include building this research resource capacity, producing scientists trained to conduct rigorous comparative effectiveness and implementation research, and embracing innovative strategies to set research priorities in these areas.