Reproducibility and validity of a quantitative FFQ designed for patients with type 2 diabetes mellitus from southern Brazil

Abstract

Objective: To evaluate the reproducibility and validity of a previously constructed FFQ to assess the usual diet of patients with type 2 diabetes mellitus (T2DM). Design: Cross-sectional survey using two quantitative FFQ (1-month interval) supported by a food photograph portfolio, a 3 d weighed diet record (WDR) and urinary N output measurement (as a biomarker of protein intake). Setting: Group of Nutrition in Endocrinology, southern Brazil. Subjects: Out-patients with T2DM. Results: From a total of 104 eligible T2DM patients, eighty-eight were included in the evaluation of FFQ reproducibility and seventy-two provided data for the validity study. The intakes estimated from the two FFQ did not differ (P . 0?05) and the correlation coefficients were significant (P , 0?01) for energy and nutrients, ranging from 0?451 (soluble fibre) to 0?936 (PUFA). Regarding the validity evaluation, data from the FFQ were higher than those from the WDR for total (28?3 %), soluble (27?4 %) and insoluble fibres (29?1 %), and SFA (13?5 %), MUFA (11?1 %) and total lipids (9?2 %; all P , 0?05). There were significant correlation coefficients between the FFQ and WDR for most nutrients, when adjusted for energy intake and de-attenuated. Also, the Bland-Altman plots between the FFQ and WDR for energy and macronutrient intakes showed that the FFQ may be used as alternative method to the WDR. The validity coefficient (using the method of triads) for the FFQ protein intake was 0?522 (95 % CI 0?414, 0?597). Conclusions: This quantitative FFQ was valid and precise to assess the usual diet of patients with T2DM, according to its validity and reproducibility.

Eating Patterns and Health Outcomes in Patients With Type 2 Diabetes

“…Moreover, in our study, some methodological precautions were also taken into account. We used a food frequency questionnaire previously constructed [ 17 ] and validated [ 18 ] in patients from Southern Brazil, and the macronutrient and micronutrient data were adjusted for energy using the residual method [ 5 ]. Also, the sample size we used to analyze a food consumption tool was appropriately calculated [ 46 ].…”

“…Information on food intake was collected from a quantitative food frequency questionnaire (FFQ) previously constructed [ 17 ] and validated [ 18 ] in patients from Southern Brazil. The FFQ consist of 98 food items and covered the past 12 months of food intake.…”

Basal metabolic rate in Brazilian patients with type 2 diabetes: comparison between measured and estimated values

“…The usual diet was evaluated by the quantitative food frequency questionnaire (FFQ) previously validated for patients with diabetes which details 80 items divided into 10 food groups (27).…”

Validity of a Short Food Frequency Questionnaire Assessing Macronutrient and Fiber Intakes in Patients of Han Chinese Descent with Type 2 Diabetes

“…Compared to other means of dietary assessment, which often require much training, FFQs are less expensive and less difficult to administer despite the crude information they are thought to provide [ 8 ]. Multiple dietary recalls [ 9 ], food records [ 10 , 11 ], or biomarkers [ 12 , 13 ] are generally accepted to provide more accurate estimates of nutrient intakes, and they often serve as reference when validating newly developed FFQs.…”