![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
2
*
Agricultural Research Service, U.S. Department of Agriculture, Washington DC 20250,
Office of Dietary Supplements and the
Office of Prevention Research and International Programs, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, MD 20892
2To whom correspondence should be addressed. E-mail: piccianm{at}od.nih.gov
 |
ABSTRACT |
|---|
 TOP ABSTRACT CURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
KEY WORDS: • food intake • supplement intake • survey methodology • dietary recall • data capture
Dietary data collection and capture are designed to provide a representation of intakes from food and dietary supplements that will allow for accurate and reliable nutrient intake estimation. Intake of foods is also used to craft dietary guidance and evaluate the risks associated with food-borne hazards. The methods used for obtaining food and dietary supplement information must be integrated to produce reliable estimates of usual total dietary intake.
This paper provides an overview of past and present dietary survey methods. The methodologies used in the National Health and Nutrition Examination Survey (NHANES)4 1999–2001 and the integrated dietary component of NHANES 2002 (entitled What We Eat in America–NHANES; referred to here as the "integrated survey") are discussed. Current issues, concerns and data gaps are identified. Future considerations about obtaining additional information on food and supplement intake in the survey are discussed. Finally, members of key stakeholder communities involved in the design, implementation and data utilization of national nutrition monitoring systems who participated in the discussion groups provided recommendations on short- and long-term strategies for enhancing dietary collection methods.
|
CURRENT KNOWLEDGE OF INTAKES |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
Historically, NHANES has been conducted to assess the health and nutritional status of the U.S. population using interview and health examination methods. Three national surveys were completed between 1971 and 1994: NHANES I (1971–1975), NHANES II (1976–1980) and NHANES III (1988–1994). Hispanic HANES, a special survey of three Hispanic subgroups, was conducted from 1982 to 1984 to provide comprehensive health and nutrition data on three major Hispanic subgroups—Mexican Americans, Cuban Americans and Puerto Ricans. NHANES III (1988–1994) was conducted in two 3-y phases, each representing a national sample. Data from the entire 6-y sample may be combined to form a larger national sample. NHANES became a continuous, annual survey program in 1999. Currently, the NHANES survey is conducted on a national sample of 6000 people of all ages, 
5000 of whom are examined and provide data for the What We Eat in America–NHANES dietary component of the survey and data release. The survey teams visit 15 survey locations each year.
NHANES data.
NHANES data are used to estimate the prevalence of selected diseases and risk factors; prepare reference data for a wide range of nutrition and health parameters; examine secular trends in the prevalence of disease, nutritional status and health risk factors; and develop hypotheses about the etiology of chronic diseases in the U.S. population. Official data releases and analyses from NHANES surveys are published in National Center for Health Statistics (NCHS) Series 11 Reports of the Vital and Health Statistics series, Advance Data from Vital and Health Statistics and peer-reviewed journals. The Centers for Disease Control and Prevention (1
) and NHANES (2
) Web sites include detailed information about NCHS publications; NHANES design and content, including questionnaires; and survey operations information.
NHANES components. NHANES dietary assessment methods have always included 24-h dietary recall interviews and supporting questionnaire information. Food frequency questionnaires were used in NHANES from 1971 to 1994. Targeted food frequency questions are currently asked in the continuous NHANES. A pilot study of a more comprehensive nonquantified food frequency questionnaire was implemented in NHANES 2002.
Information on vitamin and mineral dietary supplement use was collected in NHANES from 1971 to 1994. The scope of the NHANES dietary supplements component questionnaire was expanded in 1999 to include all types of dietary supplements (i.e., nutrients, botanicals and other types of bioactive components with presumed health benefit).
Dietary intake data vary across the different versions of NHANES. Consequently, data users are advised to review specific NHANES survey materials to verify the questionnaire content of a particular survey. NHANES interviews conducted since 1988 include questions on food assistance and school meal program participation, food security, alcohol consumption, medication use, plain water consumption, table salt use and diet behavior.
The NHANES consist of two primary components, the household interview and the health examination. Nutrition and dietary information are collected in both of these components. The dietary interview is part of the health examination component. A brief summary of the major topic areas covered over the years on these topics is provided in Table 1
. The content, format and data collection methodologies used to collect NHANES data changed across surveys. Survey data file documentation, planning guides and publications describe the methods and content of each survey in greater detail. Major and minor NHANES questionnaire modifications are implemented each year. Recent versions of questionnaires used in the continuous NHANES program are posted on the NHANES Web site (2
).
|
Overview.
The U.S. Department of Agriculture (USDA) has collected national food consumption data for > 70 y to monitor food use and food consumption patterns in the U.S. population. Table 2
provides an overview of USDA nationwide food surveys. Early small-scale studies were begun at the beginning of the 20th century to help people achieve good diets at low cost. Nationwide surveys of household use of food were conducted in 1955, 1965–1966, 1977–1978 and 1987–1988. Nationwide surveys of dietary intakes by individuals were conducted in 1965–1966, 1977–1978, 1985–1986, 1987–1988, 1989–1991, 1994–1996 and 1998. The 24-h dietary recall was used in the more recent 1994–1996 and 1998 CSFII surveys. Two recent intake surveys, 1989–1991 and 1994–1996, were coupled with the Diet and Health Knowledge Survey, a telephone follow-up survey designed to measure attitudes and knowledge about diet and health among Americans.
|
Microdata, technical databases, survey operations and questionnaires from the more recent USDA surveys are available on CD-ROM from the National Technical Information Center (3
). USDA food consumption survey results are published in USDA’s Nationwide Food Survey Report Series and peer-reviewed journals. The Food Surveys Research Group’s Web site contains > 500 tables of summarized data and detailed information about USDA food surveys, including recent survey questionnaires and a searchable bibliography of over 1000 published reports and journal papers from USDA surveys (4
).
CSFII components.
The content and data collection methodologies used to collect USDA nationwide food consumption surveys have changed across surveys to take advantage of research and technology advancements. Survey microdata files and documentation and publications describe the content and methodology used for each survey. For the most recent 1994–1996 and 1998 CSFII, the three major components include the household interview, the d-1 and d-2 individual intake interviews and the diet and health knowledge interview. The household interview included a series of questions about the educational and employment status of household members 15 y and older, household income, food assistance program participation, food expenditures and other food-related practices. The two individual intake interviews were conducted on individuals of all ages with an in-person 24-h food recall using the multiple-pass method. The 2nd-d recall was conducted 3–10 d after the d-1 interview but not on the same day of the week. Additional food-related questions followed the recall. The diet and health knowledge interview, conducted on adults by telephone 2–3 wk after the d-2 intake interview was completed, covered knowledge, behavior and attitudes about diet and health issues.
|
CURRENT INTAKES |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
|
METHODS FOR COLLECTION OF INTAKES IN THE INTEGRATED SURVEY |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
The methods for collection of information on food and dietary supplement intakes in the national surveys have evolved over the years. Table 3
presents a summary of dietary data collected in prior versions of NHANES as well as in the current integrated survey. Table 4
presents details from the diet-related questionnaires used in 1994–1996 CSFII, NHANES 1999–2001 and the integrated survey. The descriptions that follow concentrate on the most recent surveys and the collection techniques used to document intakes in them.
|
|
). The research for the new method was built on the triple-pass method for collecting 24-h dietary recalls that was used successfully in NHANES III 1988–1994 and NHANES 1994–1996 and in the CSFII 1994–1998. Improvements were based on methodological research and were designed to enhance respondent engagement throughout the interview by providing a variety of memory cues at different times to assist the respondent in remembering foods. The Automated Multiple Pass Method guides the interviewer through the expanded 5-pass recall. First, respondents are asked to list, without interruption, all foods and beverages consumed in 24 h on the day before the interview ("quick list"). Second, respondents are asked about forgotten foods and answer a series of questions probing for any forgotten foods from 9 categories (nonalcoholic beverages, alcoholic beverages, sweets, savory snacks, fruits, vegetables, cheeses, breads and rolls and any other foods). Third, they are asked about the time and name of eating occasion for each food reported. Fourth, a series of standardized questions probe for detailed information about each food reported and the amount of the food eaten ("detail cycle"). Additional information is elicited about where the food or most ingredients were obtained and where each eating occasion took place. Eating occasions and times between occasions are also reviewed. Fifth, respondents are asked whether anything else was consumed.
The design of the interview includes standardized questions and possible response options for the many types of foods available in the United States, with each response option programmed to be followed by the next appropriate question. Preliminary results from a pilot study show that the new automated method is an improvement over previous methods. Dietary supplement information is not queried or included as part of the dietary recall but it is collected separately during the household interview. The USDA Automated Multiple Pass Method may be amenable to the collection of intakes of dietary supplements, specifically of nutrient supplements, but methods research would be necessary to determine whether this is the case. Such data might provide information on intakes of dietary supplements during study days to augment information obtained using a frequency questionnaire for estimation of usual dietary supplement intakes.
A semiautomated data collection system was used in the NHANES 1999–2001 survey. This system was developed to serve as an interim data collection application until the ARS 5-step dietary interview system was available for use. The NHANES 1999–2001 system featured a multiple-pass interview format and online food probe screens. Interviewers used the probe screens to collect detailed information about the foods and beverages reported during the survey. Data were coded manually using the University of Texas Food Intake Analysis System software (6
). As in previous NHANES, dietary supplement information was collected separately during the household interview (before the dietary interview in the mobile examination center).
Day-2 telephone dietary recall.
The 2nd-d recall of the integrated survey is conducted by telephone. At the end of the d-1 dietary recall, interviewers schedule the d-2 interview with the respondents for 3–10 d later. In addition, respondents are given a set of measuring guides and instructed on how to use them during the telephone interview. The food model booklet illustrations are similar to those used in the in-person interview. Respondents are called for the interview; those who do not have a phone are given a toll-free number to call for the interview. Research to evaluate the effectiveness of conducting dietary recalls by telephone has concluded that use of the telephone is a practical, feasible and valid method for collecting 24-h recalls (7
).
Food frequency.
Targeted food frequency questions are asked in the household interview and health examination components of the integrated survey. In addition, a pilot test of a new instrument—a self-administered propensity (frequency) questionnaire—has been conducted on 700 respondents in the What We Eat in America–NHANES 2002. It is fashioned after a semiquantitative food frequency instrument, has over 100 questions and takes 20+ min to complete. The pilot study of the propensity questionnaire was successful regarding survey feasibility. If the propensity questionnaire is included in future surveys, it should provide valuable information on dietary intake, particularly of rare or unusual foods that may be of health significance. Table 1
describes food frequency questionnaires used in previous NHANES surveys.
Other food-related questions.
Current methods for obtaining additional information on specific foods such as legumes, milk and dark green vegetables and the specific questions asked about milk consumption, fish consumption and so forth after the dietary recall is completed are listed in Table 1
. Questions of this type asked in NHANES 1999–2001 are also given in Table 1
. Many users have found the diet and health knowledge questions of the Diet and Health Knowledge Survey useful, but it was not included in the 2002 integrated survey. These questions might be considered in modules for the integrated survey in the future.
Dietary supplement intake
Current survey. In the NHANES household interview, respondents are asked whether they have consumed any vitamins, minerals or other dietary supplements in the past 30 d, including prescription and nonprescription supplements. They are handed a card that lists various types of supplements along with examples. The list includes botanicals; fiber; single vitamins; multiple vitamins; single minerals; multiple minerals; vitamin and mineral combinations; combinations of vitamins, minerals and other products; amino acids; fish oils; gland products; and zinc lozenges. At the bottom, in smaller print, they are also told to include products formulated to improve athletic performance, muscle strength, memory and energy. If respondents have used supplements, they are asked to get the containers for these products (as well as those for antacids, analgesics and prescription medications that they have taken, which are asked about separately).
The interviewer checks to see whether the product is on a special list of 17 commonly taken supplements including single vitamins or minerals plus calcium and vitamin D, calcium and magnesium and vitamins A and D. If the product is on this list, the specific product (e.g., vitamin C) and the strength of the ingredients are recorded. If the product is not on the special list, the product name is recorded. If the product name is on the list of specific dietary supplements ("picklist"), the interviewer selects it. The manufacturer’s name and address and the product form are also recorded. The respondent is then asked how long this product or a similar type of product has been taken, on how many of the past 30 d the product was taken and how much was usually taken.
NHANES 1999–2001. In 1999–2001 the products listed on the hand card included antacids taken as a calcium supplement. (Because antacid use was queried later, this was eliminated from the supplement list in 2002.) All products, names and manufacturer information were recorded, and a product picklist was used. The interviewer asked whether the product was a single ingredient and, if so, recorded the strength. Many generic products were included in the picklist.
Suggestions for future supplement data collection. The ideal data collection method for dietary supplements would be to photograph the supplement container in the person’s home. This would provide the label information exactly as it was on the consumed product. An affordable and portable means of capturing these images has not been found, however. Barcode scanning would be helpful if the barcodes uniquely identified a single product, but this is not currently the case. Also, barcodes are often placed on outer packaging material that is generally not available to the interviewer. Asking respondents to bring their supplement containers to the mobile examination center to be scanned or photographed has been tried and has been inefficient because respondents frequently forget to bring them.
Dietary data are collected by 24-h recalls, whereas dietary supplement data are recalls over a longer period; these two types of data may be difficult to combine, although it is desirable for calculating total nutrient intakes. Various alterations may be possible. For example, if the time needed for the recall method can be shortened or if other postrecall questions are cycled out of the dietary interview, it may be possible to ask a person which of the products reported in the household interview (which would be listed on the computer screen, perhaps only those with nutrients) were taken and how much was taken in the previous 24 h. This would yield information with the same time frame as the dietary data.
Food program participation
Current questions on food program participation pertain to participation in the food stamp program; Women, Infants, and Children’s Supplemental Food Program (WIC); school lunch and breakfast program; and elderly feeding program. Food stamp questions are asked to determine which household members received food stamps in the past year, how long the food stamps were received and whether they are still being received. WIC questions include whether the household received any benefits over the past year; whether benefits are currently being received; and how long the woman, infant or child received WIC benefits for the last pregnancy or live birth. Questions on school meal programs include whether a child participant received a free, reduced-price or full-price meal; how often children had these meals; and whether children received free or reduced-price meals at summer programs. Older people are asked whether they have received any prepared meals in a community program or center and whether any Meals on Wheels have been delivered to their homes over the past 12 mo. Households are also asked whether they received emergency foods from a church, food pantry, food bank or soup kitchen.
Information on food program participation was also collected in 1994–1998 CSFII.
Other diet-related data
Questionnaire information also covers weight reduction methods; meat and poultry fat and skin trimming practices; infant feeding practices; use of special diets; and use of salt at the table, plain water consumption and alcohol consumption; Table 4
lists questionnaire topics. Diet and health knowledge questions would be useful to include in future modules. Specific data on food selection, preparation and usage patterns that influence food-borne disease might also be collected in future modules.
Comparability of intake collection techniques in recent surveys
Because national survey data are often used for constructing time series that compare present with past intakes, the differences in data collection methods between surveys may obscure true differences over time due to changes in food consumption. Statistical analyses and bridging studies to estimate the size of errors due to methodological differences between earlier surveys in the 1970s, 1980s and early 1990s as well as in the more recent 1999–2001 and 2002 surveys are needed so that appropriate correction factors can be applied. Research is also needed on two comparable groups studied during the same time period with both methods so that true differences and those due to changes in methodology can be sorted out. The most dramatic methodological differences are probably evident between data collected in the late 1970s (NHANES II) and 1980s (NHANES III) and mid-1990s (CSFII) and the more recent surveys that have used more advanced dietary collection methods. These errors are of concern for presenting time series data on trends in dietary intakes.
|
SUMMARY OF DISCUSSION GROUP DELIBERATIONS AND RECOMMENDATIONS |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
), included members from the range of stakeholder groups who attended the workshop, who represented the spectrum of federal agencies, academic programs and organizations involved in the national nutrition monitoring. Data collection methods: strengths
The many strengths of the current survey identified by workshop participants are listed in Table 5
. The complete NHANES provides population-based information on food and supplement intakes and related data on nutritional and health status on a representative sample of noninstitutionalized individuals in the United States. The discussion groups viewed the ability of NHANES to link dietary and other food-related data with anthropometric, biochemical, clinical and disease history information as extremely valuable in developing a more complete picture of nutritional risk and various health problems. Linking dietary and nutrition status data to other data sets, such as Medicare records and the National Death Index, will make it feasible to study the long-term outcomes of nutritional and other problems. With appropriate resources, it is possible to oversample groups at high nutritional risk, such as the elderly and children, and if necessary to adapt interview methods to their capabilities.
|
The dietary supplement data collected reflect usual intake in the past 30 d. The strength of this method is that usual intake for a clearly defined period is reported. The data collection method is designed to capture specific information on the exact product taken and specific details of its use over a defined period. Almost no other nationally representative surveys are able to do this and at present no others do. However, long-term recall is required and information on intraindividual variation in dietary supplement intakes over that period is not provided.
Data collection methods: problems, gaps and constraints
Problems, gaps and constraints identified by the discussion groups are listed in Table 6
. Dietary recall data, no matter how carefully collected, have certain well-known inherent limitations, including problems of validity and reliability. The shortcomings are discussed in greater detail in the workshop paper on estimation of intakes (9
). Neither 24-h recalls nor food frequency propensity questionnaires can completely overcome these problems. However, some of these errors and biases can be measured. Researchers at the National Cancer Institute have recently analyzed data from a large study in which doubly labeled water and 24-h urinary nitrogen were used. The results of those analyses provided valuable information on the structure of measurement error and the extent of underreporting (10
,11
) that will contribute to this error. Researchers at the USDA are beginning a similar study that should provide valuable information on the extent of underestimation of intakes, correlations between energy outputs and physical activity levels and how well intakes correlate with biomarkers of specific nutrients.
|
The discussion groups recognized that competing priorities also constitute a constraint that makes it difficult to collect all the dietary information that users desire. The integrated survey is a health and nutrition survey. As such, the available resources must cover a wide range of topics and program priorities. Although a wide range of questionnaire topics are included in the survey, discretionary topics that can be linked to the health examination component generally have priority.
Sample size was also acknowledged to be another constraint for some analytical uses. The current survey sample size in any given year is limited to 5000 respondents. For some purposes, much larger sample sizes are needed. The discussion groups were aware that fiscal constraints might limit the opportunity to increase sample sizes to accommodate these needs. Each year only some vulnerable groups can be targeted for oversampling. Currently, these groups include pregnant women, Mexican Americans, African Americans and persons aged 60+ y. The primary uses of the survey need to be formally stated and appropriate sample sizes for each use can then be calculated.
The discussion groups delineated a number of resource constraints. Paramount among them were the availability of only three mobile examination centers (MEC) for use in the survey and the inability to expand its sample size. Unless additional MEC are purchased, outfitted and staffed, it will be difficult to address the latter issue. The discussion groups strongly endorsed a long-term planning effort to place all components of the survey on a firmer financial foundation.
Confidentiality concerns were another area that the discussion groups concluded would complicate data release activities for nutrition survey programs, including NHANES and its What We Eat in America–NHANES dietary component. Data disclosure concerns necessitate that a minimum of 2 y of data be included in any NHANES public release file, and some components will not be released to the general public. The NCHS Research Data Center allows data users to access restricted data in a manner that protects the identity of survey participants.
Food intake. More information than is currently collected may be needed to determine amounts consumed from fortified foods and whether foods with various bioactive components are being eaten (e.g., stanol esters, sulforaphanes). The consequence of insufficient information on intakes of these foods could mean that some questions of particular interest to health and regulatory agency officials may not be answerable. Also, intakes of foods that may be high in certain toxic metals, such as methylmercury from fish and shellfish, may not be estimable because existing survey questionnaires may not obtain information on the origin or specific type of fish. Geographic areas of high consumption of the suspect foods may not be included in the population sampling frame.
Another set of issues identified by the discussion groups included food safety concerns and those related to insufficient detail about consumption of specific food items, such as raw milk and raw fish, which may pose risks of certain food-borne illnesses. The preparation and holding of foods such as chicken or potato salad is also important in developing data on risky practices that may result in the transmission of food-borne illnesses. Details obtained on current surveys may be insufficient for such purposes. The emerging issues related to food safety and national security may receive much more attention in the future and may require more extensive survey data. However, other surveillance methods rather than the monitoring of individual behavior might be more appropriate for this issue (12
).
Only 2 d of food intake are collected in the current integrated survey. For some individuals with highly variable intakes, usual intakes may not be captured. Information on rarely eaten foods may also not be captured.
Data collection methods have changed since NHANES 1999–2001 and even more radically since earlier versions of CSFII and NHANES. The discussion groups recommended that the size of these methodological differences must be assessed and the data must be adjusted accordingly.
Dietary supplement intake. Assessment of dietary supplement intake is complicated because discretionary patterns of supplement use may be different from those of certain foods (e.g., periodic rather than constant). Also, everyone eats food but only some people use dietary supplements. The methods for best capturing these data are still evolving.
Whether the interviewers are always able to obtain information on the strength of each dietary supplement product is questionable. Product names are not clearly presented on supplement containers, and matching of reported products to known products in the database is difficult. Manufacturer addresses include only city and state, and finding complete addresses for manufacturers or retailers can often be difficult. Manufacturers and retailers may choose not to respond to requests for labels or may be suspicious of federal government requests for these. Products change over time, some more frequently than others, and it may not be clear which version of the product was used by a respondent. Some of the products reported may be old and their labels may no longer be available. Product labels change frequently, even without ingredients changing, making matching of a reported supplement and an existing one difficult. Additionally, many types of dietary supplements are marketed and peoples’ usage patterns differ in many ways. Databases for supplements are often incomplete. For example, data are not analytically substantiated and label data are used to assign values to products in the databases.
Respondent burden is a critical factor in the interview, and recording of dietary supplement information is time consuming.
Total diet: food plus dietary supplements. Information on intakes of food and dietary supplements is collected by different methods. Dietary intake information is collected using two 24-h recalls but do not include a 24-h recall of dietary supplement intake. Dietary supplement intake information is collected using a recall that covers 1 mo before the 2 recall days. This may create problems and errors in estimating total nutrient intakes for a specific day. The validity of dietary supplement recall has not been addressed, nor have priorities been established so that use of specific supplements can be probed in greater detail. Food recalls are collected over 2 d, and such estimates may not reflect usual intakes of some individuals. The discussion groups concluded that the optimal method for collecting information on nutrient intake from dietary supplements needs to be explored so that estimates of total intakes from food and dietary supplementary sources are captured with minimal error.
|
DISCUSSION GROUP RECOMMENDATIONS |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
.
|
The survey must be based on sample sizes that are adequate for the timely evaluation of subgroups at nutritional and food safety risk. Careful evaluation of sample size is suggested because of the additional variability introduced by the recent increase in the prevalence of dietary supplement use. The current sample size of 10,000 in 2 y is likely to be insufficient to meet critical data needs related to monitoring, surveillance and risk assessment of certain subgroups.
The discussion groups deemed it essential to be able to merge nutrient intake estimates from food and dietary supplements with food data to give complete profiles of total nutrient intake that are required for assessing diet, health and disease relationships. Assessment of intake of foods, food groups and dietary supplements is also important for evaluating national food-based dietary guidance programs and for determining the food sources of nutrients deemed to be of public health significance. Eventually, it will be important to expand efforts to other bioactive food components.
The user community should have access to survey instruments and should be asked for input when instruments are developed or revised. Its opinion should be sought on key questions. Furthermore, the user community should be involved with the review of the present survey questions to discuss the advisability of their continued use.
The discussion group also endorsed the formation of a planning group to provide technical and policy input and oversight to guide the evolution of the survey over time. Such a group would identify emerging public health and nutrition issues that the survey should address and discuss technical components of the survey, including data collection issues (e.g., level of probing), coding and food composition databases and would ensure that decision making is documented. The group would seek outside expertise in key areas as needed. Moreover, the group would serve as a link to nonfederal stakeholders by soliciting input and disseminating information. It would also disseminate information about the survey data and its value to stakeholder agencies and Congressional representatives. The oversight group would be involved in reviewing topics and monitoring overall activities involving the survey.
|
ACKNOWLEDGMENTS |
|---|
|
FOOTNOTES |
|---|
3 P. Peter Basiotis, Mary M. Bender, Bernadette K. Bindewald, Alicia L. Carriquiry, Anne K. Courtney, Nancy T. Crane, Kevin W. Dodd, Katie Egan, Kathleen C. Ellwood, Susan E. Gebhardt, Joanne F. Guthrie, James M. Harnly, Joanne M. Holden, Clifford Johnson, Susan M. Krebs-Smith, Paul M. Kuznesof, Carol E. Lang, Margaret McDowell, Alanna Moshfegh, Pamela R. Pehrsson, Kathy Radimer, Amy F. Subar, Christine A. Swanson and Wayne R. Wolf.
4 Abbreviations used: ARS, Agricultural Research Service; CSFII, Continuing Survey of Food Intakes by Individuals; MEC, mobile examination center; NCHS, National Center for Health Statistics; NHANES, National Health and Nutrition Examination Survey; USDA, U.S. Department of Agriculture; WIC, Women, Infants, and Children’s Supplemental Food Program.
|
LITERATURE CITED |
|---|
|
TOPABSTRACTCURRENT KNOWLEDGE OF INTAKESCURRENT INTAKESMETHODS FOR COLLECTION OF...SUMMARY OF DISCUSSION GROUP...DISCUSSION GROUP RECOMMENDATIONSLITERATURE CITED |
|---|
1. Centers for Disease Control and Prevention () Available at http://www.cdc.gov/(accessed September 20, 2002).
2. National Center for Health Statistics () National Health and Nutrition Health and Examination Survey Available at http://www.cdc.gov/nchs/nhanes.htm (accessed September 20, 2002).
3. National Technical Information Center () Ordering Methods Available at http://www.ntis.gov/support/ordering.htm (accessed September 21, 2002).
4. Food Surveys Research Group () What We Eat in America Available at http://www.barc.usda. gov/bhnrc/foodsurvey/home.htm (accessed September 23, 2002).
5. Conway, J. M., Ingwersen, L. A. & Moshfegh, A. (2001) Effectiveness of the USDA 5-Step Multiple-Pass Method to Assess Food Intake in Obese and Non-obese Women Available at http://www.nal.usda.gov/ttic/tektran/data/000012/92/0000129284.html (accessed September 23, 2002).
6. University of Texas–Houston Health Science Center (2002) Food Intake Analysis System Available at http://www.sph.uth.tmc.edu:8052/hnc/FIAS/soft.htm (accessed September 21.
7. Casey, P. H., Goolsby, S. L., Lensing, S. Y., Perloff, B. P. & Bogle, M. L. (1999) The use of telephone interview methodology to obtain 24-h dietary recalls. J. Am. Diet. Assoc. 99:1406-1411.[Medline]
8. Dwyer, D., Picciano, M. F. & Raiten, D. J. (2003) Introduction. Future directions for the integrated CSFII-NHANES: What We Eat in America–NHANES. J. Nutr. 133:576S-581S.
9. Dwyer, J., Picciano, M. F. & Raiten, D. J., Members of the Steering Committee (2003) Estimation of usual intakes: What We Eat in America–NHANES. J. Nutr. 133:609S-623S.
10. Subar, A. F., Kipnis, V., Troiano, R. P., Midthune, D., Schoeller, D. A., Bingham, S., Sharbaugh, C. O., Trabulsi, J., Runswick, S., Ballard-Barbash, R., Sunshine, J. & Schatzkin, A. (2003) Using intake biomarkers to evaluate the extent of dietary misreporting in a large sample of adults: the Observing Protein and Energy Nutrition (OPEN) study. Am. J. Epidemiol. (in press).
11. Kipnis, V., Subar, A. F., Midthune, D., Freedman, L. S., Ballard-Barbash, R., Troiano, R. P., Bingham, S., Schoeller, D. A., Schatzkin, A. & Carroll, R. J. (2003) The structure of dietary measurement error: results of the OPEN biomarker study. Am. J. Epidemiol. (in press).
12. Woteki, C. E., Facinoli, S. L. & Schor, D. (2001) Keep food safe to eat: healthful food must be safe as well as nutritious. J. Nutr. 131:502S-509S.
This article has been cited by other articles:
|
|
 |
|
  K. J Duffey and B. M Popkin High-fructose corn syrup: is this what's for dinner? Am. J. Clinical Nutrition, December 1, 2008; 88(6): 1722S - 1732S. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. J. Duffey, P. Gordon-Larsen, G. X. Ayala, and B. M. Popkin Birthplace Is Associated with More Adverse Dietary Profiles for US-Born Than for Foreign-Born Latino Adults J. Nutr., December 1, 2008; 138(12): 2428 - 2435. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. O Fisher, N. F Butte, P. M Mendoza, T. A Wilson, E. A Hodges, K. C Reidy, and D. Deming Overestimation of infant and toddler energy intake by 24-h recall compared with weighed food records Am. J. Clinical Nutrition, August 1, 2008; 88(2): 407 - 415. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Rajeshwari, T. A. Nicklas, S.-J. Yang, and G. S. Berenson Longitudinal Changes in Intake and Food Sources of Calcium from Childhood to Young Adulthood: The Bogalusa Heart Study J. Am. Coll. Nutr., August 1, 2004; 23(4): 341 - 350. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
