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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #236635

Title: Opportunities and challenges in conducting systematic reviews to support development of nutrient reference values: vitamin A as an example

Author
item Russell, Robert
item CHUNG, MEI
item BALK, ETHAN
item ATKINSON, STEPHANIE
item GIOVANNUCCI, EDWARD
item IP, STANLEY
item Lichtenstein, Alice
item MAYNE, SUSAN TAYLOR
item RAMAN, GOWRI
item ROSS, CATHERINE

Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/2/2009
Publication Date: 3/1/2009
Citation: Russell, R., Chung, M., Balk, E.M., Atkinson, S., Giovannucci, E.L., Ip, S., Lichtenstein, A.H., Mayne, S., Raman, G., Ross, C.A. 2009. Opportunities and challenges in conducting systematic reviews to support development of nutrient reference values: vitamin A as an example. American Journal of Clinical Nutrition. 89:728-733.

Interpretive Summary: Dietary reference values have significant public health and policy implications. Given the significance of these guidelines it is important to have a set of explicit, objective and transparent methods for determining these values. In order to establish this, a group of experts in the area of vitamin A and evidence based methodology representing academic institutions and federal government agencies participated in discussions, and conducted exercises in formulating questions and evidence review criteria that could be used to conduct a systematic review using vitamin A as an example. Approaches to reviewing the scientific literature, performing literature searches on the questions to identify potentially relevant publications, and identifying challenges and limitations were developed. The workgroup concluded that following these guidelines the systematic review approach could be used to inform the development of reference values. Challenges identified include: establish criteria to be used to prioritize and define research questions when the volume of literature is large, rely on intermediate (surrogate) outcomes when few or no studies directly linking nutrient intake with clinical outcomes are available, and determine reliable biomarkers of nutrient intake. Adopting an objective, unbiased systematic review of defined questions as outlined by this group could be useful; not only in helping to set nutrient reference values, but also for increasing the transparency of the decision making process.

Technical Abstract: Nutrient reference values have significant public health and policy implications. Given the importance of defining reliable nutrient reference values, there is a need for an explicit, objective, and transparent process to set these values. The Tufts Medical Center Evidence-based Practice Center assembled a group of nutrition experts from academic institutions and federal government agencies, led participants in discussions, conducted exercises in formulating questions and evidence review criteria that would be amenable to systematic reviews of the scientific literature, performed a literature search on the questions to identify potentially relevant publications, and identified challenges and limitations of applying this method to support the development of nutrient reference values, using vitamin A as an example. The workgroup concluded that the systematic review approach could be productively used to inform the development of reference values. Challenges identified in this exercise include prioritizing and defining research questions when the volume of literature is large, relying on intermediate (surrogate) outcomes when few or no studies directly linked nutrient intake with clinical outcomes are available, and determining reliable nutrient biomarkers. Ultimately, an objective, unbiased systematic review of a defined question could be useful; not only in helping to set nutrient reference values, but also for increasing the transparency of the decision making process.