National Health Interview Survey
According to a nationwide government survey released in May 2004, 36 percent of U.S. adults aged 18 years and over use some form of CAM.
CAM is defined as a group of diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine. When prayer specifically for health reasons is included in the definition of CAM, the number of U.S. adults using some form of CAM in the past year rises to 62 percent.
Citation: Barnes P, Powell-Griner E, McFann K, Nahin R. CDC Advance Data Report #343. Complementary and Alternative Medicine Use Among Adults: United States, 2002. May 27, 2004. (536KB PDF)