Simultaneous/multiple cause-delay (SIMCAD): an epidemiological approach to projecting mortality.

Methods being used to project mortality are based on the hypothetical elimination of one or more diseases from the population or on extrapolation from observed mortality rates. This research presents an alternative projection method based on an epidemiological theory of aging and mortality change that is consistent with recent mortality transitions. The model is founded on the observation that recent mortality declines in the United States are attributable to improved life styles and advances in the prevention and treatment of degenerative diseases and that the risk of dying from such diseases is being redistributed (or delayed) from younger to older ages. A test using U.S. mortality and population data indicates that this alternative method is promising--particularly for projecting mortality rates from major chronic degenerative diseases among populations in middle and older ages.