This study updates information from the 1990 survey of VHA ICUs and provides the first assessment of regional variation in levels of ICU care in the largest integrated health-care system in the United States. In the two articles reporting on ICU organization in the United States from the early 1990s, results were aggregated to the entire United States. The 1991 survey reported in these studies preceded development of ICU levels, so results were not presented by level of care. Subsequent work using databases from existing sources also preceded development of ICU levels, and use of existing databases limits the ability to assess level of ICU.
As a result of the 2004 study we report here, the VHA adopted a system defining four levels of intensive care, rather than the three proposed [...]