Age-Adjusted Death Rate – When comparing rates over time or across different populations, crude rates (the number of deaths per 100,000 persons) can be misleading because differences in the age distributions of the various populations are not considered. since death is age-dependent, the comparison of crude rates of death can be especially deceptive.
Age-adjusted rates take into account the diverse age distributions of the populations. Valid comparisons between age-adjusted rates can be made, provided the same standard population and age groups have been used in the calculation of the rates. The direct method of adjustment was used to produce the age-adjusted rates for this report. In this method, the population is first divided into reasonable homogeneous age ranges, and the age-specific rate is calculated for each age range; then, each age-specific rate is weighted by multiplying it by the proportion of the standard population in the respective age group. The age-adjusted rate is the sum of the weighted age-specific rates. Further information regarding the calculation of age-adjusted rates can be found in The Methods and materials of Demography by Henry S. Shryock, Jacob S. Siegel and Associates, U.S. Department of Commerce.
Previous Indiana Mortality Reports used the 1940 standard million population for age adjusting. Beginning with this report, the 2000 standard million population will be used for age-adjusting death rates. Since different standard populations were used in the previous reports, those rates are not comparable to the rates published in this report.
Cause of Death Classification – The death statistics presented in this report were compiled in accordance with the World Health Organization regulations, which specifies that member nations classify causes of death by the current International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10). Mortality Reports for 1978 through 1998 used ICD-9.
Population – The 1999 population estimates were prepared by the United States Bureau of the Census.
Reliability of Rates – Some of the rates shown in this report are based on a small population, a small number of deaths, or both. The rates based on small numbers may be unstable due to random chance factors, and should be used with caution. Rates for counties with small populations also may vary considerably from year to year. In addition, allowances must be made for differences in age distributions, etc., when rates are not age-adjusted.