There are limitations to using ACS data. In addition to the absence of biological risk factor information and tobacco-use information, the ACS survey data are collected under privacy and confidentiality provisions of the U.S. Census Bureau (Title 13, US Federal Code); therefore, the full database can only be analyzed within the U.S. Census Bureau by those with explicit authorization. See Data Availability page for the options.

The assurance of confidentiality of Census Bureau data is provided by Title 13 of the United States Code (U.S.C.). As such, MDAC operational procedures carefully follow the well-defined practices designed to maintain the confidentiality of personal records as required by Title 13. These practices include the prevention of disclosure through the elimination of sparse cells in publications, the prohibited release of small-area geographical information on the MDAC public-use files, the use of an individually assigned MDAC control number to identify records instead of the use of personal identifiers for these purposes, and the restriction of persons having direct access to the MDAC database. A violation of Title 13 restrictions includes loss of job and assessment of severe penalties including a prison term of up to 5 years and/or fines of up to $500,000, for any individual found guilty of releasing confidential information. In addition, any data acquired from an external agency for MDAC purposes is acquired under the same strict confidentiality protections and practices of Title 13.