Thinking One Step Ahead: Strategies to Strengthen Epidemiological Data for Use in Risk Assessment

Risk assessment is a cornerstone of environmental health research and policy making. A commentary in this issue of EHP presents a set of recommendations and guidelines to help researchers more effectively characterize uncertainty in epidemiological findings. 2 Not only will this provide more transparency for the science itself, says coauthor Jennifer Pierson, a scientific program manager at the ILSI Health and Environmental Sciences Institute, it should also lead to more sound policies when those findings are integrated into risk assessments. " Risk assessment is nothing magical; it's a process to guide decision making. As with any kind of scientific question, it's important to know how certain we are of our data, " says Thomas Burke, director of the Johns Hopkins Risk Science and Public Policy Institute, who was not involved with the commentary. " We can't ever fully eliminate uncertainty, but we can describe it and put bounds around it with statistics. " Experimental data have traditionally formed the basis for most human health risk assessments, but increasingly regulators are recognizing the value of epidemiological data for this purpose. " Different types of studies, like toxicology studies in animals and epidemiological studies in humans, can help compensate for each other's inherent weaknesses, " says Michael Dourson, director of Toxicology Excellence for Risk Assessment, a public health organization located in Cincinnati, Ohio. Dourson was not involved with the commentary. In October 2012 Pierson and colleagues convened a workshop with more than 30 environmental health researchers to develop recommendations for characterizing uncertainty in epidemiological studies. Their recommendations and guidelines form the basis of the new commentary. To Pierson, one of the most important first steps is to get study authors out of their respective silos. " Oftentimes, the epidemiologists don't work with the toxicologists, who don't work with the risk assessors , " she says. By working together from the earliest planning stages of a study, researchers can pool their knowledge to limit uncertainty through study design, rather than scrambling to fix problems at the end. Addressing uncertainty is critical when writing up results so that policy makers can factor it into their appraisal of the literature. Pierson and colleagues recommend that investigators assess and comment on the uncertainty in their findings using a tiered system developed by the National Research Council. This system enables policy makers to rate the quality of epidemiological data and how well study findings can be generalized …