Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Alzheimer Dis Assoc Disord. 2011 Jan-Mar;25(1):49-57. doi: 10.1097/WAD.0b013e3181f333d6.

Reliability and validity of food frequency questionnaire and nutrient biomarkers in elders with and without mild cognitive impairment.

Author information

  • 1Department of Neurology, Oregon Health and Science University, Portland, OR 97239, USA. bowmang@ohsu.edu

Abstract

INTRODUCTION:

There is great interest in the nutritional strategies for the prevention of age-related cognitive decline, yet the best methods for nutritional assessment in the populations at risk for dementia are still evolving. Our study objective was to examine the reliability and validity of the 2 common nutritional assessments (plasma nutrient biomarkers and Food Frequency Questionnaire) in the people at risk for dementia.

METHODS:

Thirty-eight elders, half with amnestic-mild cognitive impairment were recruited. Nutritional assessments were collected together at the baseline and again at 1 month. Intraclass and Pearson correlation coefficients quantified reliability and validity.

RESULTS:

Twenty-six nutrients were examined. The reliability was very good or better for 77% (20/26, intraclass correlation coefficients or ICC ≥0.75) of the plasma nutrient biomarkers and for 88% of the food frequency questionnaires (FFQ) estimates. Twelve of the nutrient biomarkers were as reliable as the commonly measured plasma cholesterol (ICC≥0.92). FFQ and plasma long-chain fatty acids (docosahexaenoic acid, r=0.39, eicosapentaenoic acid, r=0.39) and carotenoids (α-carotene, r=0.49; lutein + zeaxanthin, r=0.48; β-carotene, r=0.43; β-cryptoxanthin, r=0.41) were correlated, but these significant correlations were present only in non-impaired elders.

CONCLUSION:

The reliability and validity of the FFQ and nutrient biomarkers vary according to the nutrient of interest. Memory deficit attenuates validity and inflates reliability of FFQ reports. Many plasma nutrient biomarkers have very good reliability over 1-month, regardless of memory state. This objective method can circumvent sources of error seen in other less direct and subjective methods of nutritional assessment.

Copyright © 2011 by Lippincott Williams & Wilkins

PMID:
20856100
[PubMed - indexed for MEDLINE]
PMCID:
PMC3042482
Free PMC Article

Images from this publication.See all images (2)Free text

Figure 1
Figure 2
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Lippincott Williams & Wilkins Icon for PubMed Central
    Loading ...
    Write to the Help Desk