Comparison of additive and multiplicative models of regional variation in the decline of stroke mortality in the United States.
OBJECTIVE
Although previous studies have shown that geographic variation in the decline of stroke mortality rates may be an important contributor to the changing geographic distribution of stroke mortality in the United States, some concern has been raised that this phenomenon may be model dependent. This study examines the geographic variation in the decline of stroke mortality rates in the United States with the use of both additive and multiplicative models.


METHODS
National Center for Health Statistics and Bureau of the Census data were used to assess regional-level temporal trends of underlying-cause stroke mortality rates in the United States for 1979 through 1989. Both additive and multiplicative models were fit to the data.


RESULTS
Underlying-cause stroke mortality rates have declined fairly steadily in all regions of the United States and for all race-sex groups, although there was significant regional variation in the rate of decline during the period 1979 through 1989. The South, which initially had the highest rates, had the most rapid decline for all race-sex groups when either additive or multiplicative models were used.


CONCLUSIONS
From 1979 through 1989 there was significant geographic variation in the rate of decline of stroke mortality rates, with the most rapid rates of decline in the South. As a result, there has been a decrease in interregional variation in stroke mortality rates.
Lanska
D J
DJ
Department of Neurology, University of Kentucky Medical Center, Lexington 40536-0284, USA.
Peterson
P M
PM
D000367:Age Factors; D044383:Black People; D002423:Cause of Death; D002561:Cerebrovascular Disorders / Q000453:epidemiology / Q000401:mortality*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D015146:Midwestern United States / Q000453:epidemiology; D015233:Models, Statistical; D009511:New England / Q000453:epidemiology; D015205:Northwestern United States / Q000453:epidemiology; D012044:Regression Analysis; D012737:Sex Factors; D015144:Southeastern United States / Q000453:epidemiology; D014481:United States / Q000453:epidemiology; D044465:White People; D001741:Black or African American