Development and Validation of a Semiquantitative Food Frequency Questionnaire to Assess Dietary Intake in 40-65-Year-Old Mexican Women.

BACKGROUND AND AIMS

Food frequency questionnaires (FFQ) have been widely used in epidemiologic studies since 1990s, but instruments need to be validated. The aim of this work was to create and assess the validity and reproducibility of an interview administered FFQ to be used in a Mexican women's bone health cohort study, located in Monterrey city, Mexico.

METHODS

Validation of FFQ formed by 11 food groups and 136 food and beverage items was performed on 40-65-year-old Mexican women (n = 200) by applying 2 FFQ (test method) and six 24-h dietary recalls (24hR, reference method; 1 per season on weekdays and 2 on weekends). Pearson correlation coefficient was calculated of both logs, transformed intakes and energy-adjusted nutrient intakes based on the residual method, and intraclass correlation coefficients were calculated.

RESULTS

The relative validity of FFQ against the average of six 24hR for intakes of energy, macronutrients, cholesterol, water, vitamins and minerals required for bone metabolism such as vitamin D, calcium, magnesium, phosphorus were obtained. Pearson coefficients of correlation show significance (p < 0.05) for the validity, 0.244-0.820 and 0.258-0.794, for energy-unadjusted and adjusted data, respectively. Reproducibility coefficients range 0.186-0.810 for energy-unadjusted data and 0.174-0.597 for energy-adjusted data. Most nutrients showed lower than 5% of misclassification.

CONCLUSION

The designed 136-item FFQ shows acceptable validity and reproducibility, and it is useful to be applied on 40-65-year-old Mexican women for the estimation of nutrient intakes in epidemiological studies.