Relative validity of the Geisinger Rural Aging Study food frequency questionnaire

Area of Science:

• Gerontology
• Nutritional Epidemiology
• Public Health

Background:

• Assessing nutritional status in older adults is crucial for maintaining health and preventing disease.
• Existing dietary assessment tools may not accurately capture nutrient intake patterns in specific populations.
• The Geisinger Rural Aging Study (GRAS) provides a valuable dataset for evaluating health interventions in older adults.

Purpose of the Study:

• To determine the relative validity of a population-specific food frequency questionnaire (FFQ) in older adults.
• To evaluate the FFQ's effectiveness in identifying nutritional risk among this demographic.
• To establish the FFQ as a reliable tool for nutritional surveillance in rural Pennsylvania.

Main Methods:

• A cross-over design was employed, with 245 older adults (aged 70-95) from the GRAS study.
• Participants completed both a population-specific FFQ and four 24-hour dietary recalls in random order.
• Energy and nutrient intakes were compared between the two assessment methods.

Main Results:

• Pearson correlation coefficients between the FFQ and dietary recalls exceeded 0.5 for most nutrients, indicating good relative validity.
• Bland-Altman plots showed close agreement for energy, folate, and zinc, particularly at lower intake levels associated with risk.
• The FFQ demonstrated good sensitivity in correctly classifying individuals at nutritional risk for key nutrients.

Conclusions:

• The population-specific FFQ is a valid instrument for assessing nutrient intake and identifying nutritional risk in older adults in rural Pennsylvania.
• The FFQ can be effectively used for nutritional surveillance and risk assessment in this demographic.
• Findings support the use of this FFQ for public health initiatives targeting older adults in similar rural settings.