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Show GLOSSARY Age-adjusted Rate An age-adjusted rate is a summary rate (similar to a weighted mean) that helps control for different age distributions when comparing populations. Age-adjusted rates are calculated by the "direct method," which takes age-specific death rates of a given population for a specified time period and compares those to a standard population for the same age distribution. Age-adjusted rates are typically standardized to the 1940 population. In some cases, rates are standardized to the 1970 population (as noted). Age-adjusted rates are reported per 100,000 population. For example, Utah has a lower percentage of older persons in its population than the general U.S. population. Thus, if crude rates of diseases commonly associated with persons 65+ years of age were compared, Utah's rate would appear lower than the national average. Age-adjustment provides more accurate comparisons than crude rates (see "Crude Rates" below) because they adjust for different distributions. Birth Rate The number of births in a given year per 1,000 population. BRFSS The Behavioral Risk Factor Surveillance Survey reported annually by the U.S. Centers for Disease Control. Crude Rate A crude rate is a ratio of the number of cases of a specified disease over the average population for that time period. Crude rates are reported per 100,000 population. General Fertility Rate The number of births per 1,000 women ages 15-44. Incidence "Incidence expresses the probability of or risk of illness in a population over a period of time. Incidence is calculated by dividing the number of new cases of a specified disease occurring in a specific period of time by the average population during the time interval."1 Morbidity Rate Rate of disease in a given population. Morbidity rates may be reported as "incidence" rates or "prevalence rates." Mortality Rate Mortality rates are calculated by dividing the number of deaths for a given disease during a specified time period by the average population during the same time interval. Natural Increase The number of births minus the number of deaths. Simple Point Prevalence Count A common research methodology where an instant measurement is used to describe the population. Expressed as a rate for a specified population, simple point prevalence count measures that proportion of a population which exhibit the trait at a particular instant. Prevalence Prevalence means the number of current cases at any given point in time. A prevalence rate is calculated by dividing the total number of cases by the total population figures at a specific point in time. Prevalence rates are not reported in Utah's Health: An Annual Review. 1 Utah Depr. of Health, Division of Community Health. Unpublished Report. Utah's Health: An Annual Review 1994 93 |