The Development of DRIs 1994-2004: Lessons Learned and New Challenges: Workshop Summary (2008)

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Appendix C Brief List of Reoccurring Workshop Discussions Crosscutting Topics Transparency • Transparency was acknowledged as an important component of enhancing future Dietary Reference Intakes (DRIs). • Some suggested that additional efforts to document decisions would be a major step toward more transparency. Precision and • Concern was expressed that, as presented, the DRI uncertainty values appear as “very certain” numbers, or at least surrounding that the level of confidence for all values is the same. reference values • Some suggested additional text or a specific risk characterization step to clarify the confidence in or precision of the established reference values; other options were also discussed, which included use of asterisks, a numeric grading system, or expressing values as a range.   This list, prepared by the rapporteurs and based on the workshop discussions, reflects sug- gestions made by presenters, discussants, and other workshop participants in relation to the workshop’s focus. It was prepared for the convenience of the reader. It should not be construed as representing recommendations or consensus statements, nor is it reflective of all topics nor the entire breadth of the discussions. 175 

176 THE DEVELOPMENT OF DRIs 1994–2004 Criteria for • A strategy for updating DRIs was identified by many as updating current an urgent matter. DRIs • Some suggested that several venues may operate simultaneously and that relevant criteria need to be established; resources were acknowledged as a stumbling block. Failure to establish • An educated estimate from scientists was recognized as reference values: No a better alternative to not developing a reference value: decision is not an A value derived from scientific judgment offers a basis option for government managers who must act regardless of the existence of a value. • Interest was expressed in determining ways to specify relative uncertainty surrounding reference values and ways to identify controversies and concerns. Stakeholder input • Considerable opportunities for input were noted. • The rigor and independence of the Institute of Medicine (IOM) process were recognized. Conceptual Underpinnings Uses and purpose of • The overall goal of planning and assessing for groups DRIs and individuals was affirmed. • Concern was expressed that the endpoints selected cause confusion about what the DRIs are intended to accomplish. Values expressed • Estimated Average Requirements (EARs) and Tolerable Upper Intake Levels (ULs) have been useful. • Recommended Dietary Allowances (RDAs) were noted as useful to many, but were also characterized as arbitrary, misused, and more appropriately established using situation-specific criteria. • Adequate Intakes (AIs) were controversial and a source of confusion. Some saw no other option; some preferred establishing an EAR with an indication of uncertainty; some suggested that AIs can be relevant to use with endpoints based on chronic disease. • Some commented that consideration should be given to whether the DRI process should focus on a core set of “numbers” needed versus providing reference values for all applications. 

APPENDIX C 177 Nature of endpoints • Challenges in setting DRIs based on chronic disease endpoints were acknowledged. • Some suggested that chronic disease endpoints (with more data, better elucidation of confounders, and newer techniques for approximating dose–response) can be placed appropriately within the spectrum of nutritional effects; others suggested that standards for chronic disease need to be addressed separately from those for prevention of deficiency. • Concerns were expressed about providing multiple endpoints for a single age/gender group because it would be confusing and undermine the purpose of DRIs. Nutrient substances • Many expressed interest in continuing to move beyond appropriate for DRI essential nutrients; some indicated that nonessential consideration substances may require a different approach; some expressed interest in limiting DRIs to essential nutrients. Road Map for DRI Development Systematic evidence- • Such reviews were acknowledged as useful and relevant based reviews if the appropriate questions are articulated for the review. • They were also recognized as not relevant for all aspects of the DRI process; there was particular interest in ensuring that scientific judgment regarding the values to be established remains within the domain of the subject matter experts. • Concern was expressed about costs and time involved. Risk assessment • Risk assessment was acknowledged as relevant to the as an organizing DRI process and as helpful in delineating roles and scheme enhancing transparency and usability of outcomes. • The need to adapt the approach specifically for use with nutrient substances was recognized. Scientific Decision-Making Criteria Selection of • The need for specific criteria was acknowledged. endpoints Approximation • Useful techniques—both statistical and biological—have of dose–response emerged and can be applied. relationship with • Concerns were expressed about statistical approaches limited data when dealing with chronic disease endpoints and about biological techniques relative to the ability to link to human outcomes. 

178 THE DEVELOPMENT OF DRIs 1994–2004 Extrapolation/ • This methodology was identified as necessary given the scaling current state of datasets, but needs a stronger scientific foundation and consistent application. Adjustment of data • Such adjustments were considered relevant to DRI uncertainty development, but need a systematic approach. Guidance for Users Organizational • Some indicated the table’s utility as a basic starting framework: 2×2 point to address DRI applications; some indicated that table it is overly simplistic and does not match real-world applications; some suggested it is too rigid. Distinction between • For some, the distinction is unclear; some indicated that individual and the interface between individuals and groups has been group applications missed; others suggested it is not a useful distinction if it causes a focus on applying the numbers rather than the underlying concepts. General guidance • The diverse needs of users were acknowledged. versus specific • Some suggested the need to separate general guidance guidance from specific guidance: Guidance for specific applications should be done on a case-by-case basis via separate reports. • There was interest in helping practitioners to obtain training and tools appropriate for their particular applications.