title: Scanning for new evidence to prioritize updates to the Dietary Reference Intakes: case studies for thiamin and phosphorus.
abstract: Dietary Reference Intakes (DRIs) are fundamental to inform national nutrition policy. However, a regular systematic review of the 51 nutrients that have DRIs has limited feasibility, and many DRIs have not been reviewed in >15 y.
  
  
  
  To address this issue, individuals (nutrient review group) who were members of the Food and Nutrition Board developed a streamlined, evidence-based methodology that could be used to identify nutrients potentially in need of a systematic review.
  
  
  
  The proposed methodology, termed an evidence scan, comprises several steps. First, an analytic framework is developed to identify markers of associations between intake of a nutrient and a corresponding clinical outcome. Next, the framework is used to direct the identification of keywords for a scan of published research that is potentially relevant to intake requirements or upper intake levels for a nutrient. Last, a panel of content experts selects the abstracts that are likely to be relevant and reviews the full publications. The results may be used to determine whether a revision of the nutrient's DRI is an immediate priority but would not supplant a comprehensive systematic evidence review.
  
  
  
  To illustrate the process, 2 nutrients were selected as case studies: thiamin and phosphorus (DRIs were last set in 1998 and 1997, respectively). Using the evidence scan for thiamin, we identified 70 potentially relevant abstracts, of which 9 full publications were reviewed. For phosphorus, 127 potentially relevant abstracts were identified, and 29 full publications were reviewed.
  
  
  
  From the review of these 2 nutrients, the nutrient review group concluded that there was insufficient new evidence to assign a high priority to a comprehensive systematic review for either thiamin or phosphorus. Evidence scanning is an efficient method of identifying DRI nutrients that are most in need of either a new or an updated systematic review.
authors.affiliation: Division of Nutritional Science, Cornell University, Ithaca, NY.
authors.forename: Patsy M
authors.initials: PM
authors.lastname: Brannon
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, IN.
authors.forename: Connie M
authors.initials: CM
authors.lastname: Weaver
authors.affiliation: Division of Preventive Medicine, School of Medicine, University of California San Diego, San Diego, CA.
authors.forename: Cheryl Am
authors.initials: CA
authors.lastname: Anderson
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois, Urbana, IL.
authors.forename: Sharon M
authors.identifier: 0000-0002-9785-4189
authors.initials: SM
authors.lastname: Donovan
authors.affiliation: University of Hawaii Cancer Center, University of Hawaii, Honolulu, HI; and.
authors.forename: Suzanne P
authors.initials: SP
authors.lastname: Murphy
authors.affiliation: Food and Nutrition Board, The National Academies of Sciences, Engineering, and Medicine, Washington, DC ayaktine@nas.edu.
authors.forename: Ann L
authors.initials: AL
authors.lastname: Yaktine
mesh_terms: D004032:Diet; D004305:Dose-Response Relationship, Drug; D019317:Evidence-Based Medicine; D006801:Humans; D015596:Nutrition Assessment; D018673:Nutrition Policy; D064887:Observational Studies as Topic; D010758:Phosphorus / Q000008:administration & dosage* / Q000032:analysis; D010865:Pilot Projects; D016032:Randomized Controlled Trials as Topic; D064167:Recommended Dietary Allowances; D018570:Risk Assessment; D013831:Thiamine / Q000008:administration & dosage* / Q000032:analysis
chemical_list: D010758:Phosphorus; D013831:Thiamine
keywords: Dietary Reference Intakes; evidence scan; phosphorus; risk-assessment framework; thiamin