Objective: To evaluate the validity and reproducibility of a 122-item intervieweradministered quantitative FFQ developed to determine food and nutrient intakes of adults in Botswana. Design: Relative validity of the FFQ was evaluated by comparing nutrient and food group intakes against four non-consecutive 24 h recalls administered over 12 months. The FFQ was repeated after 1 year to assess reproducibility. Setting: Kanye, Botswana. Subjects: Seventy-nine adults aged 18-75 years. Results: Spearman correlation coefficients for the validity of energy-adjusted nutrients ranged from 0?42 (carbohydrate) to 0?49 (protein) for macronutrients and from 0?23 (Fe) to 0?44 (PUFA) for micronutrients. Exact agreement of quartile distribution for nutrients between the FFQ and recalls ranged from 27 % to 72 %. Weighted kappa values were lowest for retinol (0?13), Fe (0?22) and b-carotene (0?25) and ranged from 0?33 (SFA) to 0?59 (folate) for other nutrients (energy, carbohydrate, protein, fat, Ca and vitamin E). Spearman correlation coefficients between the recalls and FFQ for food groups ranged from 0?18 (dark green leafy and yellow vegetables) to 0?58 (poultry). Reproducibility correlation coefficients (energy-adjusted) varied between 0?39 for retinol and 0?66 for vitamin E, with most values falling between 0?50 and 0?60. Conclusions: The FFQ had good relative validity for estimating habitual food group and nutrient intakes, but was poor for some micronutrients (Fe, retinol and b-carotene) and foods (fruits and dark green leafy vegetables).
Keywords
Quantitative FFQ Adults Validity BotswanaBotswana has undergone a rapid epidemiological transition characterized by increased incidences of non-communicable diseases, namely CVD, diabetes and cancers (1) . Dietary intake is associated with morbidity and mortality from non-communicable diseases (2) . Assessment of the usual food intake of individuals and groups is central to the investigation of eating patterns, nutrient intakes and their relationship to health outcomes, but the measurement of food and nutrient intakes can be challenging. The FFQ is used to obtain estimates of habitual diet and in contrast to other methods, such as single 24 h recalls and food records which do not reflect past diet or usual intake, has been used in a variety of settings to measure intakes in epidemiological studies. The FFQ ranks individuals according to levels of consumption rather than providing estimates of absolute quantities of energy and nutrient intakes. In addition, the technique has the advantage of being relatively easy to administer and analyse, thereby incurring lower costs compared with other methods of dietary assessment (3) . The use and limitations of the FFQ have been extensively reviewed and the method can be prone to measurement errors; thus validation studies are an essential step in the development of new FFQ.Whereas FFQ have been developed and validated for many developed and developing economies, there are few published reports of validated instruments designed to mea...