Evaluating the Use of Questions and Responses in a Large National Dietary Data Collection Instrument

摘要

The U. S. Department of Agriculture's Automated Multiple Pass Method (AMPM) Blaise instrument collects 24-hour dietary recall data for the What We Eat In America (WWEIA), the dietary interview component of the National Health and Nutrition Examination Survey (NHANES). AMPM contains over 2,400 questions and more than 21,000 responses about foods with each response determining the next appropriate question. This results in approximately 500,000 possible paths through the questions within the AMPM. Each year it is used in approximately 9,000 interviews which ask individuals to recall the foods and beverages that were consumed the day before the interview. On average, 13 foods are reported for each 24-hour dietary recall and 10 questions are asked about each food. Of the 10 questions, 6 are probes about the description of the food and the amount consumed. During each year of the survey, interviewers use AMPM to ask respondents over a million questions about foods. AMPM has been in continuous use since January of 2002 and in that time has been used to conduct over 60,000 dietary intake interviews. A large comprehensive update that includes major procedural changes is done for the beginning of each two-year survey period. A smaller update incorporating primarily new foods and portions is done as necessary for the second survey year. Updates are made to questions, response values, and to programming which controls what questions are asked based on previous responses. The purpose of the updates is to assure validity and completeness of the dietary data. These updates result from changes in the food supply and in food consumption patterns, and evaluation of the use of the questions and responses.