Definition of Terms

Natality (Births)

Adjacent States – States that border Indiana, including Illinois, Kentucky, Michigan and Ohio.

Age – This refers to age in years as self-reported by the individuals listed in the tables.

Age-Specific Birth Rate – This is the number o f live births for a specific age group (e.g. 20-24) for every 1,000 females in that age group.  For example, in 2000 there were 204 live births to Allen County females age 15-17.  There are 7,258 females ages 15-17 in the county.  Thus:

                        (204/7,258) * 1,000 = 28.1 age-specific birth rate

Birth Weight – The amount a liveborn infant weighs at birth, in grams.

Crude Birth Rate – The number of live births per 1,000 population in a year.

Education Level – The education levels reported in these reports reflect the highest grade completed.

First Trimester – The first three months of pregnancy.

General Fertility Rate – The number of live births per 1,000 women aged 15-44 in a year.

Live Birth – A live birth is any infant who breathes or shows any other evidence of live (such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles) after separation from the mother’s uterus, regardless of the duration of gestation.

Live Birth Order – The number of liveborn children including the current birth.  In multiple deliveries (e.g. twins or triplets), the live birth order increases sequentially with each child delivered.

Low Birth Weight (LBW) – An infant with a birth weight of less than 2,500 grams (5 pounds 8 ounces).

Married – Includes currently married women and those who are separated but not divorced.

Multiple Birth – The number of live births that resulted from multiple pregnancies (i.e. a twin, triplet, etc.).  Our reports only indicate the number of births from the multiple pregnancy that were delivered alive, not the number of multiple pregnancies that occurred to Indiana women.  Since some multiple pregnancies may result in both live births and stillborn fetuses, the total number of multiple births may not be an even multiple of the specified multiple pregnancy (e.g., an odd number of twins).

Neonatal – The first 28 days of an infant’s life.

Not Married – This refers to women who were never married and those who are divorced or widowed.

Preterm Birth – This is the delivery of a liveborn infant prior to 37 weeks gestation.

Primary Cesarean – A woman’s first cesarean delivery.

Race – This refers to the race of the mother or father.  In natality reports, race is categorized as “white”, “black”, “other”, and “total”, where “other” means all other races besides white and black, including unknown.  “Total” represents all races combined.  In Indiana, “Hispanic” is classified as an individual’s ethnicity, not his or her race.  All Hispanics are classified as either “white Hispanic”, “black Hispanic” or “other Hispanic”. 

Resident Birth – The birth of an infant whose mother’s usual residence is in Indiana, regardless of where the birth occurred (within Indiana or elsewhere).

Teen Mother – A female between the ages of 10 to 19 years.

Very Low Birth Weight (VLBW) – An infant with a birth weight less than 1,500 grams (3 pounds 5 ounces).

Unmarried Parents – At the time of delivery, the mother was not married to her infant’s father.  The term formerly used was “out-of-wedlock”.

Mortality (Deaths)

Age-Adjusted Death Rate – When comparing mortality 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-dependant, the comparison of crude rates of death can be especially deceptive, especially between a county with a high number of older residents compared to a county with a much younger population. 

Age-adjusted rates take into account the diverse distributions of the populations.  Valid comparisons between age-adjusted rates can be made, provided the same standard population (U.S. standard million) and age groups have been used in the calculation of the rates.  The direct method of adjustment is used in our mortality reports.  In this method, the population is first divided into reasonable homogeneous age ranges (usually five- or ten-year age groups), 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.  This is the reason why there can be 50 deaths in a county from one cause of death and 50 deaths from another cause, and the age-adjusted death rate will not be the same, since it is dependent on the age at death.

Prior to 1999, the 1940 U.S. standard million was used to calculate the age-adjusted death rate, and the 1970 standard million was used to calculate deaths from cancer.  For 1999 on, the 2000 U.S. standard million was used.  A comparison cannot be made between the 1940, 1970 and 2000 U.S. standard million.

Cause of Death Classification – The death statistics presented in our reports 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.  When comparing most causes of death for years using ICD-10 (1999 forward), there will not be an exact match to data in previous reports that used ICD-9.

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