Nomination for New Dietary Reference Intakes Reviews

The Canadian and U.S. governments are offering the opportunity to nominate nutrients for review, to be considered by the Federal Dietary Reference Intake (DRI) Committees of both countries as they undertake the task of prioritizing nutrients for government-funded reviews of Dietary Reference Intakes. Nominations will be accepted through 11:59 pm EDT on July 31, 2013.

Below please find information related to:

• Background
• Developing a Nomination
• Submitting a Nomination
• Further Information

Background

The Canadian and U.S. governments have each established Federal Dietary Reference Intake (DRI) Committees that work collaboratively to identify DRI needs and to coordinate government sponsorship of DRI reviews and related activities. The DRIs - which reflect nutrient reference values essential to national nutrition policies and to professionals working in the field of nutrition and health - have been developed under the auspices of the Institute of Medicine with funding from the Canadian and U.S. governments.

The DRI reports, issued between 1997 and 2011, are available via the  National Academies Press website or from the  USDA National Agricultural Library website.

Prioritization of DRI Reviews

The two government DRI Committees are jointly responsible for prioritizing nutrients for government-funded reviews and subsequent commissioning of an expert review to establish reference values. The DRI Committees prioritize new reviews based on evidence of significant, new, and relevant data since the last DRI review, as well as relevance to current public health concerns. They also work to determine that any methodological issues that could impede a new review, especially those identified previously, have been resolved. The availability of funds is also a factor in the initiation of DRI reviews.

Significant, new, and relevant data are characterized as follows:

• "Significant" data refers to the overall scientific quality of the evidence, number of new studies, consistency of the results and whether the new study results appear to expand the DRI-related information available to the original DRI expert panel. Of particular interest are randomized controlled trials of high scientific quality.
• "New" refers to research that was unlikely to have been available to the previous DRI expert panel.
• "Relevant" means that the study results are generalizable to the North American population and to DRI development.

Decision to Seek Input Regarding Nutrients of Interest

As the DRI Committees consider future reviews of the current DRIs, they are cognizant of the broad range of uses of the DRIs. Because of this, the DRI Committees recognize the importance of input from individuals and organizations both within and outside the government in making future DRI prioritization decisions. Therefore, the DRI Committees have established a nomination process to help in planning for new DRI reviews of nutrients and related substances reviewed in previous DRI reports.  The process is briefly outlined below.

Developing a Nomination

Input from all interested parties is welcome. Input may come from individuals and organizations external to the federal government as well as from federal agencies.

The opportunity to provide information is limited at this time to new reviews for nutrients and related substances reviewed in previous DRI reports.

The submission of a nomination does not guarantee the initiation of a DRI review.

The nomination will be regarded as information which may be used by the DRI Committees in planning activities. The nominations will be considered jointly by the Canadian and U.S. committees. Proprietary or confidential information cannot be considered and should not be submitted.

Information included in the nomination should be relevant to DRI decisions. Notably, the effect of the nutrient(s) should be generalizable to a nutrient adequacy/risk reduction or safety context; the evidence should include information on causal relationships between intakes and these health-related outcomes of interest, as well as quantitative dose-response relationships; and information should be applicable to the general North American population within a dietary context.

The nomination consists of two parts: a cover letter and a literature search.

To request an electronic copy of the templates for the cover letter and literature search please send an email to DRI.nominations.ANREF@hc-sc.gc.ca with "Request for DRI Nomination Templates" in the subject line.

Part I. Cover Letter

A cover letter--no more than two pages in length in Microsoft Word format-- must be submitted using the template provided and should be constructed to describe why a nutrient, or a small group of highly interrelated nutrients, warrants a DRI review at this time.

Relevant information in the cover letter should be informed by the comprehensive literature search, which is the second part of the nomination submission.

The two-page cover letter should provide:

• The rationale for DRI review consideration, including a discussion of why the nominator believes that such a review addresses current public health concerns.
• A description of how the new evidence available since the most recent DRI review justifies a new review. Note: As part of this discussion, the availability of intervention trials to demonstrate a causal relationship between the nutrient and specified health-related outcomes, as well as the availability of studies that demonstrate quantitative dose-response relationships between intake and health-related outcome (e.g., dose ranging intervention studies and prospective cohort studies), should be highlighted.
• Description of evidence related to more than one life stage group, if available.
• Identification of any relevant methodological issues that either impeded the last DRI review of this nutrient(s) or that are generally relevant to a new review of this nutrient(s), and how these have been resolved. Note: These issues have been identified in reviews of the DRI process (for example, Reference 1 and Reference 2), as well as within the specific Institute of Medicine DRI reports which may be accessed on the  National Academies Press website or the  USDA National Agricultural Library website.
• Description of evidence gaps identified by the past DRI expert panel and explanation about how the new evidence addresses these limitations.

Part II. Literature Search

A comprehensive, objective literature search of human studies--in the form of a listing without nominator review or analysis--must be submitted using the template provided along with the completed cover letter. The literature search should encompass all life-stage groups.

The search should focus on human studies that examine the linkage of the nutrient(s) to a health-related outcome (for example of a linkage framework, see figure 2 in Reference 3).

The search should be limited to evidence beyond the information available for the most recent DRI review.  Note: This information relates to the first step in the DRI Committees' process of deciding whether or not new, significant, and relevant human evidence is available for a new DRI review.

Documentation that evidence is available for more than one DRI life-stage group is of interest. Note: Life-stage groups are defined by sex, age, and pregnancy/lactation status.

The literature search document (Microsoft Word format) should provide:

• Description of Search Strategy used:  Identify all search terms, databases searched, languages and years included as well as other search parameters such as limits and filters applied. Human studies with high quality designs should be included (e.g., randomized controlled trials, prospective cohort studies, metabolic feeding studies). Other types of studies are outside the scope of the review and should not be included (e.g., animal, retrospective and cross-sectional studies). The search should be limited to studies published after the most recent DRI review. Refer to the most recent DRI report to determine which years to include.

  Identify all studies relevant to the nomination of the nutrient for DRI review that met the parameters described above. Systematic reviews are to be listed separately (see below). The identified studies should subsequently be subdivided into included and excluded studies.

  Included studies are those that met the initial search parameters and on subsequent review were found to be relevant to DRI development. All relevant studies should be included, regardless of the direction, size, or statistical significance of the effect. Each citation should be presented in the  standard citation format for biomedical journals (Uniform Requirement for Manuscripts).

  Following this citation style, referencing a typical journal article should take the following form:

  • List of authors, using last name then initials, followed by et al. if there are more than 6 names
  • Article title
  • Journal Name
  • Date
  • Volume (issue): page range
  • Database identifier and/or clinical trial registration number, if applicable

  As needed, conversions from citation management software into a Microsoft Word document should be carried out.

  Excluded studies are those studies identified through the literature search that met the initial search parameters and were therefore potentially useful, but on subsequent review were found to lack relevance to DRI development. Examples of non-relevant studies that should be listed as excluded are therapeutic or treatment studies in diseased populations rather than studies focused on prevention, and studies not relevant to the general North American population.
• List of Included Studies: The listing of included studies should be arranged:
  • First, by health-related outcome
  • Second, by DRI life-stage groups
  • Third, by study type within life-stage group (use categories: intervention trials; metabolic feeding studies; prospective cohort studies)
  • Fourth, in reverse chronological order (most recent first)
  Published abstracts of all included studies should be provided in this listing.
• List of Systematic Reviews:   Provide full citation and published abstract of any relevant systematic reviews published since the last DRI review in reverse chronological order.
• List of Excluded Studies:  All excluded studies (no abstracts) should be grouped together by reason for exclusion, in reverse chronological order.

Submitting a Nomination

Nominations will be accepted from April 29, 2013 to 11:59 pm EDT on July 31, 2013.

The nomination (i.e., cover letter and literature search) should be submitted by attaching the files to an email sent to the following addresses - the nomination must be emailed to both addresses simultaneously:

DRI.nominations.ANREF@hc-sc.gc.ca
DRInominations@hhs.gov

Further Information

A listing of nutrients nominated will be posted on this website after the nomination period has closed. The submitted documents will not be posted or acknowledged individually beyond a message of receipt at the time of email submission.

Questions about the nomination process can be forwarded using the email addresses listed directly above.

References

1. National Research Council.  The Development of DRIs 1994-2004: Lessons Learned and New Challenges: Workshop Summary. Washington, DC, 2008: The National Academies Press.
2. Taylor CL.  Framework for DRI Development: Components "Known" and Components "To Be Explored." Background Paper, Food and Nutrition Board, Institute of Medicine. Washington, DC, 2008.
3. Russell R, Chung M, Balk EM, et al.  Issues and Challenges in Conducting Systematic Reviews to Support Development of Nutrient Reference Values: Workshop Summary. Nutrition Research Series, Vol. 2. Rockville (MD): Agency for Healthcare Research and Quality (U.S.); 2009 Mar. (Technical Reviews, No. 17.2.)