The Development of a Quantified Food Frequency Questionnaire for Assessing Iron Nutrition in Schoolchildren from Resource-Limited Settings in Cape Town, South Africa.

Children are vulnerable to developing iron deficiency anemia, especially in resource-limited settings. Information on habitual dietary intake informs dietary interventions aimed at improving iron deficiency. Dietary assessment in school-aged children is challenging and requires concerted efforts to mitigate the pitfalls of long complex methods. Nested within an intervention trial, we aimed to obtain dietary intake information to assess iron nutrition in 8 to 13-year-old children from resource-limited settings in Cape Town, South Africa. Following careful consideration of the study objective, participant characteristics, research setting, available resources, and features of the different dietary intake assessment methods, we identified an iron quantified food frequency questionnaire (QFFQ) as the best method to obtain the information. The QFFQ reflected the study population's habitual intake and the nutrients of interest (protein, iron, vitamin A, vitamin C, calcium, zinc, and fiber). In addition, strategies such as interview-administration of the QFFQ, interviewing the child participant and caregiver together, simplifying frequency reporting, a strategic food list order and a variety of interesting portion size estimation aids collectively supported dietary intake assessment in this young study population. Using a methodical, multiphase approach and strategies that promote participant engagement, we developed the QFFQ, achieved interview success, and obtained comparable data.