Assessment of the accuracy of portion size reports using computer-based food photographs aids in the development of an automated self-administered 24-hour recall.

OBJECTIVE: To assess the accuracy of portion-size estimates and participant preferences using various presentations of digital images. DESIGN: Two observational feeding studies were conducted. In both, each participant selected and consumed foods for breakfast and lunch, buffet style, serving themselves portions of nine foods representing five forms (eg, amorphous, pieces). Serving containers were weighed unobtrusively before and after selection as was plate waste. The next day, participants used a computer software program to select photographs representing portion sizes of foods consumed the previous day. Preference information was also collected. In Study 1 (n=29), participants were presented with four different types of images (aerial photographs, angled photographs, images of mounds, and household measures) and two types of screen presentations (simultaneous images vs an empty plate that filled with images of food portions when clicked). In Study 2 (n=20), images were presented in two ways that varied by size (large vs small) and number (4 vs 8). SUBJECTS/SETTING: Convenience sample of volunteers of varying background in an office setting. STATISTICAL ANALYSES PERFORMED: Repeated-measures analysis of variance of absolute differences between actual and reported portions sizes by presentation methods. RESULTS: Accuracy results were largely not statistically significant, indicating that no one image type was most accurate. Accuracy results indicated the use of eight vs four images was more accurate. Strong participant preferences supported presenting simultaneous vs sequential images. CONCLUSIONS: These findings support the use of aerial photographs in the automated self-administered 24-hour recall. For some food forms, images of mounds or household measures are as accurate as images of food and, therefore, are a cost-effective alternative to photographs of foods.

Challenges in converting an interviewer-administered food probe database to self-administration in the National Cancer Institute Automated Self-administered 24-Hour Recall (ASA24).

The National Cancer Institute (NCI) is developing an automated, self-administered 24-hour dietary recall (ASA24) application to collect and code dietary intake data. The goal of the ASA24 development is to create a web-based dietary interview based on the US Department of Agriculture (USDA) Automated Multiple Pass Method (AMPM) instrument currently used in the National Health and Nutrition Examination Survey (NHANES). The ASA24 food list, detail probes, and portion probes were drawn from the AMPM instrument; portion-size pictures from Baylor College of Medicine's Food Intake Recording Software System (FIRSSt) were added; and the food code/portion code assignments were linked to the USDA Food and Nutrient Database for Dietary Studies (FNDDS). The requirements that the interview be self-administered and fully auto-coded presented several challenges as the AMPM probes and responses were linked with the FNDDS food codes and portion pictures. This linking was accomplished through a "food pathway," or the sequence of steps that leads from a respondent's initial food selection, through the AMPM probes and portion pictures, to the point at which a food code and gram weight portion size are assigned. The ASA24 interview database that accomplishes this contains more than 1,100 food probes and more than 2 million food pathways and will include about 10,000 pictures of individual foods depicting up to 8 portion sizes per food. The ASA24 will make the administration of multiple days of recalls in large-scale studies economical and feasible.

Formative research of a quick list for an automated self-administered 24-hour dietary recall.

Twenty-four-hour dietary recalls are used to collect high-quality dietary data. Because they require highly trained interviewers, recalls are expensive and impractical for large-scale nutrition research, leading to the use of food frequency questionnaires. We are developing a computer-based, self-administered 24-hour dietary recall for use by adults. Our goal is an easy-to-use, low-cost, publicly available, Web-enabled instrument that will include elements of the Automated Multiple Pass Method developed by the US Department of Agriculture, which uses five passes to enhance recall. The initial pass is called the "quick list" and allows respondents to report foods consumed the previous day freely, in any order, and without detail. Using a crossover design, we conducted initial formative pilot testing among 18 adults in a self-administered computer environment. We tested two versions of a "quick list" (the first Automated Multiple Pass Method pass) for remembering foods consumed the previous day: "unstructured" and "meal-based." Respondents showed a strong preference for the meal-based version (13 of 18), although positive features of both were identified. Chronological reporting was most common, although many foods were sporadically reported out of order. Versions did not appreciably differ in number of foods reported, moved, or deleted. Usability issues and preferences were also identified. If these developmental efforts prove successful, the use of affordable automated recalls could be valuable in clarifying diet-disease associations in observational epidemiologic studies and measuring dietary compliance in clinical trials. This pilot work illustrates the usefulness of formative cognitive and usability testing for questionnaire and software development.

Methodology for adding glycemic load values to the National Cancer Institute Diet History Questionnaire database.

BACKGROUND: A growing interest exists in using glycemic index and glycemic load as potentially important exposures in investigations of risk for a variety of chronic diseases. OBJECTIVE: We added values for glycemic index and glycemic load to the nutrient database of a commonly used dietary assessment instrument, the Diet History Questionnaire (DHQ). DESIGN: The nutrient database for the DHQ is based on 4,200 individual foods reported by adults in the 1994-1996 US Department of Agriculture Continuing Survey of Food Intakes by Individuals (CSFII). This list was condensed into 225 nutritionally similar groupings of individual foods. Using published glycemic index values we assigned glycemic index values to each of the individual CSFII foods in these food groups. In cases where CSFII foods did not correspond tightly to foods with published glycemic index values, we used decision criteria to assign glycemic index values. We then calculated sex- and serving size-specific glycemic load for each of the 225 food groups using the weighted mean method. Quality assessments were made to help evaluate the success of this method for assigning glycemic load values. RESULTS: Seventy-one percent of the top carbohydrate-contributing food groups had in excess of 90% of the CSFII mentions linked directly to a published glycemic index value (ie, no imputation was required), and 100% of these food groups had at least 50% of total mentions linked directly. CONCLUSIONS: Using this method, it is now possible to use DHQ responses to assess the associations between reported glycemic load and glycemic index and risk of many chronic diseases in epidemiologic studies.

Women's access to food-processing technology at the household level is associated with improved diets at the pre-harvest lean season in The Gambia.

BACKGROUND: Women's access to food processing technology at the household level may have positive dietary benefits during the pre-harvest lean season when households are most stressed from food shortages and higher energy expenditures from agricultural work. OBJECTIVE: This study in rural Gambia was conducted to determine if women's access to small manually operated oil presses (ram) for sesame oil extraction had any significant effects on seasonal fluctuations of household oil supply and on dietary intakes of women and children. METHODS: Participants were 40 women and children with access to community-based motorized oil press expellers (Expeller-control), 37 women and children with access to village-based ram presses (Press-experiment), and 43 women and children with access to both ram press and motorized expeller (Combination). Dietary data were collected at baseline, at peak oil-pressing, at pre-harvest lean, and at the post-harvest seasons. RESULTS: Households in the Press-experiment and Combination groups consumed 37 and 51 percent more oil, respectively, than those in the Expeller-control group during the pre-harvest lean season. Women from the Press-experiment and Combination groups consumed more energy at the lean season than those in the Expeller-control group. Similarly, children from the Press-experiment and Combination groups consumed more protein at peak oil-processing season than those from the Expeller-control group. At the pre-harvest season children from these two groups also consumed more protein, however, only the consumption of the Combination children was statistically significant compared with that of the Expeller-control group (p < .05). Press-experiment children consumed more nutrient-dense weaning foods during the pre-harvest lean season than Expeller-control children. CONCLUSIONS: Women's access to appropriate technology can provide the means to "add value" to their agriculture product, which may serve as an economic stabilizer with potential to increase dietary intakes and incomes, especially during the pre-harvest lean season.