There really is no one-stop source for changes in the AHS content. The major watersheds were 1973, 1985, 1997, and 2015. Below is a list of documents that will help. Unless noted otherwise, they are available from the technical documentation section of the AHS website.
- The AHS Codebook provides information about the Public Use File s and includes descriptive information on all of the AHS variables.
- The Items Booklets show the text of the questions in the survey instruments and the order in which they were asked during the interview. Access the Items Booklet for each survey under the “Questionnaires” section.
- The Historical Changes (Appendix C) is a historical changes document that lists subject areas and the years changes were made. Access the Historical Changes for each survey under the “Historical Changes” section.
- The web site's technical documentation page also includes supporting documents on topics, such as topcoding practices, dependent interviewing, and so on. Explore these documents by clicking on “Help Guides” and “Other Documentation.”
- The Variable Name Index is a comma-separated values (CSV) file that cross-indexes the survey years and the variable names in the 1973-2013 microdata. While it does not document changes in coding, it documents when certain variables were added or removed from the survey. To access the Variable Name Index, click on “Codebooks” from the Technical Documentation page.