TABLE 3.

An overview of the challenges and potential solutions in this area.

Challenges	Potential solutions
Existing evidence synthesis	•Retrospective harmonization guidelines
Biological plausibility and clinical relevance	•Examine animal and human evidence together •Measures of neural activation
Understanding test sensitivity, particularly to nutrition	•Validate test sensitivity and test-retest reliability •Keep nutritional intervention constant (for example glucose) and manipulate cognitive tests
Understanding what is “normal” and for whom	•Establish normative databases for the population of interest
Do we need a guiding taxonomy?	•Move away from a modular view of cognition •Develop a guiding taxonomy and keep it updated •In the presence of a theoretical rationale for test choice
Composite scores	•Must be performed in a theoretical manner •Include individual test scores in Supplemental Information 1
Issues in reporting	•Recommend the use of guidelines for registration and reporting (general)–for example, Centre for Open Science •Develop guidance specifically for reporting test parameters in sufficient detail
Prospective harmonization	•Set of recommended tests; can be added to researchers’ choice of test •Recommend against researchers creating their own tests •Guidance for cognitive test creation and reporting (parameters, etc.)
Test availability	•Make tests freely available •Construct an advisory database describing cognitive tests and their availability/costs
Translation of test results into health claims/substantiated product benefits	•Make claims/benefits appropriately broad/narrow
Applicability of evidence to the dietary guidelines committee questions	•More evidence is needed across the lifespan (especially early and middle adulthood) •Encourage cognitive nutrition researchers to focus more on dietary patterns •Lobby for the inclusion of the most well-supported individual nutrients in the review questions posed by the dietary guidelines committees