Comparison of results from two dietary interview methods

The objective of this study was to compare the food consumption and nutrient intakes obtained through a 24-h dietary recall (DR) and a consumption tendency interview (CTI). Both instruments DR and CTI were applied simultaneously in groups of 264 schoolchildren and 272 adults. Information on age, sex, literacy, occupation, and head of family's social security system was also obtained. Body weight and height were measured and the body mass index BMI was calculated. Food portions and nutrient intakes were described and compared by using means, standard deviation. ANOVA, and product moment Pearson' correlation. No significant differences were detected between both methods with respect to mean consumption of cereals, fruits, meats and sugars. Dairy products and oil consumption were found to be larger according to CTI: 0.6 +/- 1.7 y 0.3 +/- 0.9 portions, respectively (p < 0.01). In terms of nutrient intakes, there were no differences in beta-carotene, vitamin A, vitamin C, iron, and zinc. Mean differences of energy and selected nutrients were lower than 10% of total intake, except by omega-3 fatty acid, cholesterol, vitamin E, and folate. Correlation coefficient between both methods was < 0.4 for most foods and nutrient intakes. Correlation was slightly higher in adults regarding cereals dairy and sugar (approximately 0.5). Both methods DR and CTI produce similar results when applied at the population level, but can be significant different on individuals. The suitability of each method will depend on the objectives of the study.