Validation and reproducibility of a food frequency questionnaire to assess dietary intake of nutrients and phytochemicals in relation to certain hormone-dependent tumors in Argentina.

PEROVIC NR, DEFAGÓ MD, AGUINALDO A, JOEKES S, ACTIS AB

Barcelona

Congreso; 1º Congreso Mundial de Nutrición en Salud Pública y 7º Congreso de la Sociedad Española de Nutrición Comunitaria; 2006

Sociedad Española de Nutrición Comunitaria

The purpose of the present study was to analyze the validity and reproducibility of a food frequency questionnaire (FFQ) aimed at assessing lipid and phytochemical intake in order to estimate its association with salivary, mammary and prostate tumor risk in Argentina. The FFQ was administered to 45 people of both sexes, aged between 20 and 72 years old and resident in Cordoba, Argentina. The FFQ included 257 questions referring to foods, their consumption frequency and portion size. Regarding consumption of fruit and vegetables, the season was also taken into account. The questionnaire was applied at two different periods (FFQ1 and FFQ2) with a break of six months in between. As a reference, the 24-hour dietary recall was used (24HDR) three times. By means of the program Interfood, the intake of food was converted into the daily consumption rate of nutrients and phytochemicals. The mid intake of FFQ1-FFQ2, the 24HDR-FFQ2 median intake, median difference, Mean Absolute Deviation from the median differences (MAD), Wilcoxon signed rank sum test and Spearman rank order correlation coefficients were calculated to analyze the accuracy of the FFQ data. The correlation coefficients for FFQ1-FFQ2 varied from 0.52 for tymnodonic fatty acid to 0.89 for butyric fatty acid (mean=0.80), with p<0.05. For 24HDR-FFQ2, the values ranged from 0.19 for lycopene to 0.93 for tymnodonic fatty acid (mean= 0.58), with p<0.05 in 83% of the cases. The analysis carried out showed an acceptable validity and reproducibility of the FFQ, thus enabling it to be used in research related to the intake of lipids and phytochemicals and the risk of developing certain hormone-dependent tumors.