Agreement between Dietary Intake of Older Adults and Proxy Respondents Assessed by a Food Frequency Questionnaire

Validity and reliability of a food frequency questionnaire for community dwelling older adults in a Mediterranean country: Lebanon

Background

Food frequency questionnaires (FFQ) is an easy and inexpensive tool that can be used to evaluate nutrient and dietary trends of groups and individuals. Few studies in the East Mediterranean region tailored FFQs to describe dietary intakes of older adults. The purpose of the study is therefore to assess the validity and reproducibility of a FFQ, designed for use with older adults living in a Mediterranean Arabic speaking country, Lebanon.

Methods

The FFQ is composed of a list of 90 food items, commonly consumed by adults above 60 years of age. Validity of the FFQ was tested using the mean of two 24-hours dietary recalls (24HDR), and reproducibility, by repeating the questionnaire within a one-month period, along the second dietary recall. Our study included 42 and 76 participants, for the repoducibility and validity analysis respectively. Subjects were randomly selected from 2 of the 8 governorates in the country.

Results

FFQ reproducibility showed a mean relative difference of 1.03% without any significant difference between all paired components of nutrients. Intra class correlation (ICC) showed good and excellent reliability for caloric intake and all macronutrients, moderate to good reliability for all remaining nutrients, except for poly-unsaturated fatty acids, vitamins A, B12 and fibers. Correlation coefficients for all nutrients were fair to strong. Both administrations of the FFQ showed good internal validity. Validation of FFQ showed a mean relative difference between FFQ and mean 24HDR at 19.5%. Agreements between the 2 methods, for classifying individuals in the same or adjacent quartile, for nutrient intake and nutrient adequacy, were 80 and 78.2% respectively. Mean Kappa coefficient was 0.56 and energy-adjusted correlations were within the recommended values for all items except for vitamin A and B12. Adjusting for nutrient-dense food intake improved the agreement for theses 2 vitamins to 0.49 and 0.56, respectively.

Conclusion

The proposed FFQ can be considered a valid tool to help describe nutrient intake of older individuals in an Arabic speaking Mediterranean country. It could serve for possible use in the East Mediterranean region for the evaluation of regular dietary intake of community-dwelling older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-022-00788-8.

Misreporting of Energy Intake in Older People: Comparison of Two Dietary Assessment Methods

Accurate assessment of dietary intake is essential in clinical practice and research. While energy intake (EI) misreporting has been extensively studied in the general population, relatively little is known about misreporting among older people. This cross-sectional study used clinical data routinely collected in 127 participants, aged 70-96 years, from the Toulouse Frailty Clinic. EI was assessed by diet history interview and three-day food record. Misreporters were identified with the Goldberg cut-off method, using the Harris-Benedict equation to estimate total energy expenditure. The response rate was 66% for three-day food record and 93% for diet history interviews. EI from diet history interviews (1799 ± 416 kcal/day) was significantly higher than from food records (1400 ± 381 kcal/day; p < 0.001) and closest to total energy expenditure (1758 ± 437 kcal/day; (p > 0.05). Thirty percent of participants were identified as underreporters with three-day food records vs. 9% with diet history interviews. Overreporters were found with diet history interviews only (11% of participants). In older people, the diet history interview has the advantage of obtaining a higher response rate and a lower underreporting rate, compared to three-day food record. Nevertheless, with this method, overreporting was observed and interpreting results should be done with caution.