Age adjustment is the application of age-specific rates in a population of interest to a standardized age distribution. It enhances the comparability of populations by controlling for the effects of their differing age compositions. The age-adjusted rate for a population of interest can be compared to that of a different age-adjusted population at the same point in time or the same population at a different point in time. Age-adjusted rates in WISH are calculated using the direct method based on the year 2000 Standard U.S. population.
The mortality rate is calculated by dividing the number of deaths per year by the population. It is usually expressed as the number of deaths per 100,000 population. The rate may refer to deaths in a specific group, or to deaths from a specific cause, or to all deaths in the entire population. The rate may be adjusted for the age composition of the group or it may be the observed (or "crude") rate.
Rates by Race/Ethnicity
The population estimates used as denominators for the mortality rates in WISH are based on the bridged race estimates provided by the U.S. Census Bureau and the National Center for Health Statistics (NCHS). The estimates have been controlled so they sum to the annual estimates published by the Office of Health Informatics.
Producing the bridged race estimates was necessary because race categories in Census 2000 differed from those used in previous years. Specifically, data on race from Census 2000 were not directly comparable to data from previous years due, in large part, to giving respondents the option to report more than one race.
As a result, NCHS and the Census Bureau produced bridged race estimates that allow calculation of rates by race/ethnicity across years. These estimates distribute (or "bridge") the "more than one race" and "some other race" populations into one of four major race groups (American Indian/Alaska Native, Asian/Pacific Islander, Black, and White) and two ethnicity groups (Hispanic/Latino, non-Hispanic/Latino).
NCHS and the Census Bureau have produced this set of bridged race estimates extending back to the 1990 Census, and plan to produce these estimates on an annual basis in the future. WISH will be updated each year as these estimates become available.
External Cause of Death
WISH displays Wisconsin injury mortality data by external cause of death or mechanism of injury (e.g., fall, fire/flames, firearm, poisoning, and suffocation) and by intent or manner of death (e.g., suicide, homicide, unintentional injury).
All 1999 and later injury mortality statistics are based on codes in the International Classification of Disease -10th Revision (ICD-10). ICD-10 is used in various countries worldwide for coding deaths. The ICD-10 codes include code sets for types of disease, medical procedures, and external causes of injury.
All 1998 and earlier injury mortality statistics are based on codes in the International Classification of Disease - 9th Revision (ICD-9). ICD-9 is used in various countries worldwide in medical reports. The ICD-9 codes include code sets for types of disease, injuries, and poisonings as well as external cause of injury (E codes).
The WISH external causes of injury groupings are consistent with standard ICD-9 and ICD-10 code groupings for reporting injury mortality data developed by CDC's National Center for Injury Prevention and Control (NCIPC), CDC's National Center for Health Statistics, and the American Public Health Association. See ICD Injury Matrices.
The numbers of deaths by external cause of injury come from annual mortality data prepared in the Vital Records Section, Office of Health Informatics. For more information, visit the Wisconsin Department of Health Services Web page for death statistics.