Click for next page ( 46


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 45
1 4 IDENTIFICATION OF CURRENT AND POTENTIAL USES OF SURVEY DATA As part of its pro ject charge, the Committee developed and conducted a workshop for select academic, government, and incus try users o f survey data followed by a symposium that brought together other interested cur- rent and potential users of the data. After gathering information from these conferences, the Committee was deco evaluate the material developed, identify specific user needs, and report its findings and recommendations for survey strategies and methodologies to the funding agencies. This Chapter describes the Committee process and presents some general con- cepts of user needs developed from those data users' conferences. DATA USERS ' CONFERENCES . . _ The workshop (June 1983 ~ and sympos ium (October 1983 ~ were des igned to review current data uses and accumulate information on procedures used to gather survey data in both the NFCS and the dietary component of the NHANES . Par t i c i pants in tines e con fer ence ~ inc. luded cur ren t and pa ten t i a 1 users of food consumption survey data from the nutrition and health aca- demic community, and the food industry and scientists from the legis- lative and executive branches of the government. The workshop was designed to examine specific data uses and applica- tions. The invited participants in this workshop were primary data users -- that is, those from academia, government, and the private sector who used the data tapes. Most workshop participants were persons who used data from both the NFCS and the NHANES. The larger public symposium was intended to provide the Committee with information from a broader, more general audience of current and potential data users. The more than 250 registrants at the symposium included both those who used data tapes and those who used published reports of the information developed from survey data. WORKSHOP . The workshop agenda and a list of participants are included in Appendix B. The agenda provided background information to participants on three ma jar surveys: the NFCS, the NHANES, and the Consumer Expenditure Survey (CES ~ of the Department of Labor . Information about the CES was included to permit assessment of the type of information

OCR for page 45
46 collected and to provide a basis for comparing information from the CES with that from the NFCS. In planning the workshop, the Committee had several objectives: To identify primary uses of national data on food consumption. To learn why persons or groups use the data. To identify the kinds of data most needed by these persons or groups. To make preliminary assessments of the surveys in providing the data needed by these per sons or groups. Many of the workshop participants were identi fled as us ing the NHANES and the NFCS data tapes conjointly. Some were also identified as being familiar with the CES data. Participants provided the Committee with information con- cerning specific uses of the data, the data bases preferred for those uses, data base information needed to improve those uses, and how the data bases compared in providing other needed information. The workshop discussions were designed to provide information about cur- rent and emerging uses of survey data. In addition, specific suggestions for modifying survey design and reporting procedures to augment the usefulness of the data were provided to the Committee. General aspects of these workshop recommendations were discussed during its final plenary session. Toward this purpose, the Committee developed a systematic approach to examining issues of definition of data needed and of requisite precision and reliability of data (Appendix A). The approach was used in the workshop. As a result certain issues became apparent with regard to most purposes (e.g., documentation, timeliness); other issues were more use-specific (e.g., required quality of measures and precision of estimate). The Committee reviewed the workshop information to identify gaps in its own information-gathering process. This process helped to ensure that addi- tional useful information court be included in the symposium to follow. SYMPOS IUM C. The symposium agenda and a lie t of participants are included in Appendix The symposium had several objectives: To expand the information-gathering ef forts of the Committee, in par- ticular by identifying additional user of and needs for data and data release products (including published reports).

OCR for page 45
To identify scientific concerns that affect current and future survey methods, data reporting, and survey use . To identify modifications in survey design or data reporting that meet the identified uses. To assess the potential impact of suggested survey modifications. The symposium included presentations by Committee members and invited speakers. Speakers discussed examples of data applications for both national and local needs. Because the study involved both the NFCS (with its Household Food Use and Individual Dietary Intake phases ~ and the NHANES dietary com- ponent data, the symposium incorporated an opportunity to identify user needs for greater compatibility and comparability of the data developed by the separate surveys. Announcements and notices of the symposium were sent to a number of scien- tific journals and to other publications directed toward the membership of the food, nutrition, health, consumer issues, and statistical communities. The Committee included in the design of the symposium an effort to obtain infor- mation both from users attending the conference and from users who could not attend. Materials provided to all potential registrants and in public infor- mation about the sympos ium noted that the Committee welcomed comments from those who could not attend the sympos ium. GENERAL CONCEPTS RELATED TO DATA USERS AND NEEDS , The specific recommendations developed as a result of the workshop and symposium discussions are presented in Chapters 6 and 7. However, some general concepts that emerged from these discussions are described below. WIDE VARIETY OF USES A major finding during information-gathering efforts was the wide variety of uses for the survey data. Table 4-1 lists the interests of data users who regis tered at the sympos ium. Clearly, the data are used for foodand nutrition-related issues . However, the range of identified uses was found to go far beyond traditional food and nutrition concerns. Users indicated needs for the data in address ing ques- tions related to agricultural production of food and fiber, as well as eco- nomic demand analyses and socioeconomic analyses of consumption. Questions related to food safety and toxicology reportedly have been addressed with these data, as have questions related to the design and marketing of new or improved foot products.

OCR for page 45
48 In some instances, data users focused on uses of one particular data base, e .g ., the NFC~ Individual Dietary Intake data. In other ins lances, data users needed or wanted to use more than one data base, e.g., the NFCS conjointly with the NHANES. Some specific uses required conjoint use of both the NFCS and NHANES data bases with private-sector data bases. For many uses, distribution information beyond that provided by simply classifying conquers and looking at group means is required. For example, toxicologic considerations are relates to the occurrence of high intake and many nutr itional ques tions are related to the prevalence of low intake. The availability of distribution information adds an important dimension to data use. LINKAGE TO OTHER DATA BASES In cases where multiple data base (i.e., con joint) use was identified as a user need, an important concern was improvement of comparability and compati- bility of the survey data bases contributing to that conjoint use. The ability to put information from one system together with that of another and thus "link" the data was regarded as a necessity for wider and more effective use of the data. - It should be noted that such linkage, to facilitate integrated use of separate data bases, may require the inclusion of individual identifiers (e.g., name, address, date of birth, and Social Security number) in each data base. The Committee expects that inclusion of such identifiers will require special government clearances. Data users did not look on the Present limited overlap in data between the surveys as redundant or unnecessary but rather as a set of data points ~ , providing an opportunity for data linkage between survey data bases. For this reason, the Committee chose to incorporate a specific discussion of its per- spective on such conjoint uses of food consumption data in its report (see Chapter 5~. Linkage to nondietary data bases also can have great importance. For example, information from dietary surveys is especially useful when it can be linked to data on health, disease prevalences, mortality, and demographic characteristics of surveyed populations. Additional information on potential confounding factors (e.g., smoking) may help in the interpretation of data. T IMPLY DATA REPORT ING The timely release of survey data was a commonly identified user need. The data users, as would be expected, supported the data-collection efforts of USDA and DHHS. A consistent recommendation of data users, however, was for an

OCR for page 45
- 49 - increased effort to_gollect, process, and release the data in a timely manner. In the view of the Committee, timely data release and reporting warrant high priority. MORE SPECIFIC DATA In general, data users wanted the surveys to provide even more data than now provided and even more specific data than now retained and available on data tapes. A frequent recommendation was that the survey data be collected and reported in a manner that would provide highly detailed information not only about foods themselves, but also about their nutrients, added substances, and contaminants. Users' need for data bases that contain specific and detailed information rest on the ability of individual users to aggregate specific data; if the data are already aggregated before release, they cannot be disaggregated. DATA USES: OVERVIEW A simple but effective way of summarizing uses of survey data is to consider that the data provide answers to basic questions -- "who," "what," "how," "when," and "where." As illustrated in Table 4-2, each of these basic questions involves a number of factors that cross disciplines and interests. For example, detailed and specific identification of who is consuming food is needed not only for assessing determinants of food and nutrition status, but also for designing' analyzing, or modifying a variety of food-related assis- tance, education, and regulatory programs. The recommendations developed as a result of the workshop, symposium, and Committee discussions and Committee review of earlier reports 13,1 have implications for survey design, data reporting, and data use alone or in combination. Where con joint uses of data from different surveys are involved, recommendations applicable to one survey could have implications for another. This would be particularly true if the data from the separate surveys were used to monitor the nutrition status of the U. S. population. For example, the work of the Joint (USDA/DHHS) Nutrition Monitoring Evaluation Committee wit 1 require use of the separate survey data bases. For this reason, the Committee viewed these conjoint uses of the separate data bases as an important aspect of its overall assessment and recommendation process . Therefore, a Committee perspective on conjoint uses of the separate survey data bases is included in Chapter 5. SU~fARY Through a workshop and a symposium, the Committee gathered information about uses for national survey data on food consumption and dietary intake. The Committee's review involved primarily USDA's NFCS and the dietary

OCR for page 45
- 50 - component of NHANES. The type ant extent of food consumption information col- lected by the~tonsumer Expenditure Survey of the Department of Labor were also reviewed. The Committee noted that there are a wide variety of uses for food con- sumption ant dietary intake data. Data are needed not only for food and nutrition questions considered "traditional," but also for a wide range of uses, including public health, epidemiology, food safety, agricultural pro- duction, and the economics of food and fiber consumption. Data users indicated a need for greater comparability and compatibility between data bases and more timely reporting of data. Users frequently iden- tified a need for retention of more specific (less aggregated) data on data tapes and in published reports. Some user needs were found to be common to all data users. These common needs became the focus of the Committee's recom- mendations for near-term implementation .

OCR for page 45
- 51 - Table 4-1 Interests of data users registering for the symposium Category of Interest Proportion of Responses,* % Research 41 Health-related** 23 Marketing 12 Agricultural programs 6 Food programs 36 Food guidance/education 15 Food assistance 13 Food safety assessment Policy considerations 22 Although registrants could respond in more than one category, lculations were based on all responses' equaling 100%. ** Category that included food, nutrient, and dietary assessments as related to health concerns.

OCR for page 45
~ 52 - Table 4-2 General concepts related to data needs and users Ques Lion Factors Data Users Who is consuming? Age; gender; race; height, All users weight; geographic area, (high priority) locality; living arrangement; urban ~ suburban ~ or rural; income; occupation; smoking hate it8; participant/ length of participation in food programs; food assistance recipient/length of assistance; individual identifiers for record linkage (may require special clearance) W _ in consumed? Foods, nutrients; food All users components, ingredients, (high priority) contaminants; foods in combination; amount; type and degree of processing Where is it consumed? At home, away from home; Specialized users type of food service How is it consumed? Type of processing, All users . preparation, cooking (high priority) When is it consumed? Meals, snacks; time Specialized users of day; seasons; day of the week 1