A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting

Web-MBIAT;Web-Meal Based Intake Assessment Tool;Food frequency questionnaire;iron;pretesting

Hussein, Areege Hassan ; Heath, Anne-Louise

University of Otago

关键词: Web-MBIAT;    Web-Meal Based Intake Assessment Tool;    Food frequency questionnaire;    iron;    pretesting;   

Others  :  https://ourarchive.otago.ac.nz/bitstream/10523/4626/1/HusseinAreege2014.MDiet.pdf

美国|英语

来源: Otago University Research Archive

【 摘 要 】

Iron deficiency is the most common nutrient disorder worldwide. To assess intake in a population, food frequency questionnaires (FFQs) are commonly used as a low-burden, cost-effective method of dietary assessment. However, most FFQs measure intake by day, and do not account for nutrient or food component interactions when eaten as a meal. This is important for non-haem iron which has absorption modifiers (e.g., vitamin C and phytate) that affect its bioavailability. The Web-Meal-Based Intake Assessment Tool (Web-MBIAT) assesses iron intake by meal, potentially allowing for these interactions to be taken into account.The first aim of this study was to generate a food list for the Web-MBIAT program that estimates the intake of iron and its absorption modifiers in premenopausal adult women (aged 19-50y) living in New Zealand. The second aim was to assess the usability of the Web-MBIAT program from the perspective of the interviewer.FOODfiles 2010 version 2.0 and literature on the phytate content of foods were used to generate two food lists. Cut-offs were set using the literature or observing a natural break in the nutrient content of foods in FOODfiles. Cut-offs for the ;;main’ food list were: iron (≥2mg/100g); vitamin C (≥7mg /100g, except ≥10mg/100g for non-alcoholic beverages); meat, fish and poultry (≥30g/100g); and phytate (≥50mg/100g). The Adult Nutrition Survey 2008/09 was used to identify food groups that contributed ≥4% to iron and ≥10% to vitamin C intake in the target population. Reasons for exclusion such as ;;similar item already in food list’, were developed to limit the food list length. Cut-offs for the ;;short’ food list were: iron (≥8mg/100g), vitamin C (≥80mg /100g) and phytate (≥750mg /100g). Staff (who were Dietitians or Nutritionists) and graduate students were recruited by email from the Department of Human Nutrition, University of Otago, as interviewers to pretest the Web-MBIAT and user’s manual. Interviewers conducted the FFQ with a standardized diet and were timed. Interviewers’ characteristics and audio recordings of their feedback were gathered, and a list of issues and suggestions were categorized for analysis. The main iron food list contained 420 items, (16% of the total number of foods in FOODfiles). The most common reason for inclusion and was meeting a specific food component cut-off (97% of inclusions). The most common reason for exclusion was a ;;similar food item already in food list’ (47% of exclusions). The short food list contained 24 items.A total of 10 interviewers were recruited. In pretesting, most interviewers were positive about the Web-MBIAT program and user’s manual. However, the main issues identified by both groups concerned the Web-MBIAT’s ;;logic and navigation’ — particularly searching food items — and the lack of colour in the user’s manual. Proposed modifications include removing case-sensitive searching of food items, assessing supplement use, and having more prompts to guide the interviewer. The next step is to modify and validate the Web-MBIAT (against weighed diet records), before future use.