National Ambulatory Medical Care Survey (NAMCS) ----------------------------------------------- The 1973-1992 and 1993- directories are a mirror of the Public-Use Data Files (micro-data) files at http://www.cdc.gov/nchs/about/major/ahcd/ahcd1.htm . Check that ( the CDC's ) website for information about the survey and how to use it. ulitimatecluster.pdf is a technical paper with instructions for combining 2003 data with years prior to 2002. http://www.cdc.gov/nchs/about/major/ahcd/namcsdes.htm has a NAMCS description. Jean Roth , jroth@nber.org , 2005-09-15