The Bureau is best known for counting the nation’s population every 10 years. In the future, the Bureau intends to collect much of the data that have traditionally been collected during the decennial census from the long-form questionnaire with the annual ACS. Beyond the decennial census, the Bureau also conducts numerous other surveys and censuses that measure changing individual and household demographics and the economic condition of the nation. Lawmakers and agency officials at the federal, state, and local levels rely on these data when they make decisions in a wide range of policy areas. Private-sector decision makers also use census data to guide their business plans. Because of the critical and varied uses of census information, it is important that the Bureau’s published data meet minimum quality standards. In addition, when the data are made public, it is equally important for the Bureau to disclose what has been done to ensure the quality of the data and identify any limitations so that potential consumers can decide whether the data are appropriate for a particular use. Some degree of error in the census (and in virtually any survey) is inevitable because of limitations in enumeration, processing, and dissemination methods and errors in responses and imputation of data for nonresponses. Given the size and diversity of the U.S. population, the effort to count the entire population and provide detailed demographic characteristics every 10 years is one of the most complex of all government operations. The Bureau devotes significant resources to minimizing error and improving the quality of the decennial census. Data quality standards and standardized quality control procedures can provide a consistent basis for making data dissemination decisions and informing the public about the quality of the data made available to it. In 2000, Congress passed what is now known as the Information Quality Act. This legislation directed OMB to issue governmentwide guidelines that “provide policy and procedural guidance to Federal agencies for ensuring and maximizing the quality, objectivity, utility, and integrity of information (including statistical information) disseminated by Federal agencies.” The legislation also required each agency to issue its own implementing guidelines that include administrative mechanisms allowing affected persons to correct information maintained and disseminated by the agency. The OMB guidelines, issued in final form in February 2002, define quality as encompassing utility, objectivity, and integrity. The guidelines require agencies to issue their own implementing guidelines by October 1, 2002. Additionally, they mandate that agencies adopt a standard of quality as a performance goal and act to incorporate data quality criteria into their data dissemination practices. The guidelines also require agencies to develop processes for reviewing the quality of data before they are disseminated. Although OMB had some general guidance for survey processes prior to the enactment of the Information Quality Act, other than requirements for the evaluation of selected monthly and quarterly economic indicators, there were no governmentwide requirements relating to the quality of data disseminated by the federal agencies. Some statistical agencies within the United States developed their own extensive guidelines and standards that apply to data disseminated to the public. In July 2001, OMB identified the statistical agencies within the Departments of Education and Energy, the National Center for Education Statistics (NCES) and the Energy Information Administration, as good examples of agencies that have developed specific guidelines to implement their broad principles and diverse professional standards. Statistical agencies in other countries have also developed good examples of comprehensive guidelines for ensuring the quality of data disseminated to the public. Since 1985, Statistics Canada, the central statistical agency of the Canadian government, has published quality guidelines for its statistical activities. Subsequently, it added guidelines on quality assurance processes and management context and developed a policy and standards on informing users about data quality. More recently, the European Union recognized the importance of comprehensive, well-documented guidelines and standards to support its task of developing high-quality, comparable statistics from member countries. All members of the European Statistical System (ESS) have signed a quality declaration and approved 22 recommendations for quality for future work within the system. To address our first question on the standards that the Bureau had in place to guide its data dissemination decisions, we interviewed census officials, reviewed relevant agency documents, talked to data users, and reviewed various complaints about the quality of 2000 Census data. We built on our prior reports about the quality of data from the 2000 Census on Hispanic subgroups and the homeless and the Bureau’s decision-making processes for its decisions on whether to release those data. We also reviewed other GAO reports addressing aspects of the Bureau’s procedures for assessing the quality of disseminated data. From these reports, we identified examples of several types of problems the Bureau encountered with 2000 Census data, which might have been alleviated if the Bureau had implemented data quality standards and procedures. Our examples of data quality problems are not comprehensive, but illustrative. To determine whether the Bureau has since developed Bureau-wide data quality standards, and, if so, whether they would likely address for the 2010 Census the data quality problems raised after the 2000 Census, we interviewed census officials responsible for developing agencywide standards, examined documents related to the development of new standards on data quality review, and reviewed the agency’s Internet site for information on data quality review standards available to the public. We also reviewed OMB guidelines on the quality of data disseminated by federal agencies as well as the action taken by the Department of Commerce and the Bureau in response to the guidelines. We attended meetings of the Secretary of Commerce’s Decennial Census Advisory Committee, the National Academy of Science Panel on Research on Future Census Methods, and the Washington Statistical Society’s conference on Quality Assurance in the Government, all of which examined issues related to the quality of the data disseminated by the Bureau. We also discussed information quality standards and guidelines with officials in Eurostat, the statistical directorate of the European Union. Additionally, we considered how the Bureau’s actions in developing dissemination guidelines could improve the quality of data disseminated after the 2010 Census and for other Bureau data collection programs, such as the ACS that among other things, is intended to replace the long-form census questionnaire. To benchmark the Bureau’s progress in developing data quality review standards with that of other statistical agencies, we also reviewed documents from entities that have developed standards for the quality of data disseminated to the public, including NCES; Statistics Canada, the central statistical agency of Canada; and ESS. However, we did not evaluate the implementation or effectiveness of these guidelines and standards or their specific applicability to the Bureau. Our work addressed only standards and guidelines on data quality review. Although OMB’s information quality guidelines and the Bureau’s guidelines and performance principals cover all the key steps in data collection, analysis, and dissemination, we did not look at the Bureau’s guidelines or standards for ensuring quality during the planning and data collection stages. Instead, as requested, we looked at Bureau guidance on steps taken after data collection, that is, guidance related to processing data, assessing their quality, and making them available to the public. We looked for documents spelling out standards, guidelines, procedures, and other criteria to guide decisions about identifying and correcting errors, determining if and when to release data, and revising data after release. Our audit work was conducted in Washington, D.C., and at the Bureau’s headquarters in Suitland, Maryland, from August 2003 through October 2004. Our work was done in accordance with generally accepted government auditing standards. We requested comments on a draft of this report from the Secretary of Commerce. On September 27, 2004, the Secretary provided written comments on the draft. The comments are reprinted in appendix I. The Bureau had no agencywide standards or guidelines in place to guide decisions about disseminating data from the 2000 Census. Instead of agencywide, written guidance, professionals within the different parts of the Bureau primarily used their judgment and program-specific practices to decide when and whether data should be released and what supporting information, if any, should accompany them. This led to instances when (1) data were released with uncorrected and undisclosed quality problems, (2) inconsistent decisions were made on whether to release data sets with similar quality problems, and (3) the reasons for certain data dissemination decisions were inadequately communicated. At the time the Bureau was making decisions about disseminating data from the 2000 Census, it did not have written, agencywide guidelines or standards to help inform its decisions on whether the data were of sufficient quality to be released. Although Bureau officials emphasized that the Bureau has a long tradition of high standards and procedures that yield quality data, they acknowledged that these practices were primarily part of the agency’s institutional knowledge. According to one official, key individuals in each program area, relying primarily on professional judgment, determined whether the quality of the data was acceptable for release to the public. The official explained that the program areas develop their own guidance and procedures for ensuring data quality. Sometimes their guidance and procedures were written, but more often they were not. Further, the Bureau had no central inventory or repository of the guidance and practices of the different divisions. As noted earlier, decennial census data are used to apportion and redistrict Congress. As release of data for each of these purposes is required by statute, they are known collectively as “public law” data. The Bureau had a number of quality assurance programs and procedures for assessing the accuracy of, and correcting errors in, public law and other data prior to their release. However, the lack of standard procedures and guidelines for dealing with quality problems contributed to lost opportunities to correct errors in the count of the population identified before the data were disseminated. One such quality assurance program we reviewed was known as Demographic Full Count Review, in which analysts were to identify, investigate, and document suspected data discrepancies or “issues” in order to clear census data files and products for subsequent processing or public release. The Bureau contracted out some of the analysts’ work because it lacked sufficient staff to conduct the Full Count Review on its own. Bureau reviewers were to determine whether and how to correct the data by weighing quality improvements against time and budget constraints.