ANIMATED FORMULAS
This link shows formulas used to calculate rates with examples.
PREGNANCY
VARIABLE INFORMATION
This link lists all available pregnancy variables in the module.
ABORTION: Purposeful termination of pregnancy with intention
other than to produce a live born infant or to remove a dead fetus.
FETAL DEATH: Death prior to the complete expulsion or
extraction from its mother of a product of human conception, irrespective of the
duration of pregnancy; the death is indicated by the fact that after such expulsion
or extraction, the fetus does not breathe or show any other evidence of life, such
as beating of the heart, pulsation of the umbilical cord, or definite movement of
voluntary muscles. (Definition recommended by World Health Organization in 1950).
A fetal death is required to be reported if the fetus has completed or passed the
twentieth week of gestation or weighs 350 grams or more. (Weight criteria effective
in 1978). Vital Statistics Laws and Regulations 61-19: Vital Statistics, Section
21(a). Heartbeats are to be distinguished from transient cardiac contractions;
respirations are to be distinguished from fleeting respiratory efforts or gasps.
LIVE BIRTH: The complete expulsion or extraction from its
mother of a product of human conception, irrespective of the duration of pregnancy,
which, after such expulsion or extraction, breathes or shows any other evidence
of life, such as beating of the heart, pulsation of the umbilical cord, or definite
movement of voluntary muscles, whether or not the umbilical cord has been cut or
the placenta is attached. (Definition recommended by World Health Organization in
1950). Heartbeats are to be distinguished from transient cardiac contractions;
respirations are to be distinguished from fleeting respiratory efforts or gasps.
MARITAL STATUS:
UNMARRIED: a woman who has never been married or who has been widowed or
legally divorced in excess of 280 days.
MARRIED: A woman who is married or has been married within 280 days from
conception.
MATERNAL AGE: The age of the mother in years at her last
birthday.
MATERNAL DEATH: Death of a woman whose cause of death
is assigned to Complicationscations of Pregnancy, Childbirth, and Puerperium (Tenth
Revision ICD O00-O99). If death occurred more than 42 days after termination of
pregnancy, the death is not considered to be pregnancy-related and is not assigned
to codes O00-O99.
PREGNANCIES: Estimated number of the sum of live births,
abortions, and fetal deaths.
RACE: Information on race of the mother and father is reported
on birth and fetal death certificates, and the race of the woman is reported on
the abortion form. For the purpose of this application, race is separated into three
categories, "White", "Black", and "Other".
To be consistent with National Center for Health Statistics and with other states,
the Office of Public Health Statistics and Information Services of the South Carolina
Department of Health and Environmental Control began utilizing the race of the mother
for births in 1990. Abortions and fetal deaths are characterized by the race of
the woman for all reported years.
RESIDENCE DATA: Data allocated to the place in South Carolina
where the person normally resides, regardless of where the event occurred.
INTERPRETATION OF DATA
RATE CALCULATIONS WITH SMALL NUMBERS: There are variations
in all statistics that are the result of chance. This characteristic is of particular
importance in classifications with small numbers of events where small variations
are proportionately large in relation to the base figure. As an example, small changes
in the number of deaths or births in small population areas or in the number of
deaths from uncommon causes could result in large changes in these crude rates.
For this reason, rates for counties with small populations or other small bases
should be used cautiously. In this report, rates are not calculated for places of
less than 2,500 population or when the number of events is less than 3 for a particular
category, due to the known instability of rates based on small numbers. In the Perinatal
Section, 3-year rates are calculated to provide a more stable base for comparison
of trends over time.
TEEN PREGNANCY RATE CALCULATIONS: The population denominator
used in the Pregnancy Module and the published South
Carolina Teen Pregnancy Data Book has been rounded to the nearest 10th.
The rates reported in this module will be identical to rates reported in previous
volumes of the South Carolina Teen Pregnancy Data Book.
FETAL DEATH RATE CALCULATIONS: Beginning in 1993, the
fetal death rate calculations were changed to the formula recommended by NCHS which
includes fetal deaths plus live births in the denominator. Due to this change, the
rates reported in this series will not be identical or comparable to rate reported
in previous volumes.
POPULATION DATA: With the exception of population data
by race and population data for selected age groups of teens, the 2000 Census data,
provided by the Office of Research and Statistics (South Carolina Budget and Control
Board), were used to calculate the rates in this report. Population data by race
and for selected age groups were modified.
POPULATION DATA BY RACE: At the time of this publication,
population files released by the U.S. Census Bureau contain data for a "multiple
race" category and for single race categories (including an "other/non-Census designated
race" category). This presents problems for vital rates from two standpoints: first,
these population files contain counts of persons with more than one race and therefore
are not compatible with vital statistics numerators which contain information for
persons by single race category, second , the population files contain the "other/non-Census
designated race" category which is not used to calculate vital statistics rates.
In order to provide rates by single race category of 'white' and 'black and other'
for South Carolina vital events, a methodology was developed that would regroup
the populations of the race categories, 'multiple race' and 'other/non-Census designated
race', into standard single race categories. This methodology was developed jointly
by the staff of the Office of Research and Statistics, South Carolina State Budget
and Control Board and the staff of the Division of Biostatistics, Public Health
Statistics and Information Services, SCDHEC. At the time of this publication, neither
modified or bridged files had been issued by the US Bureau of the Census.
Of the 4,012,012 South Carolinians counted in the 2000 Census, approximately one
percent (39,950) were included in the 'multiple' race category and another one percent
(39,926), in the 'other/non-Census designated race' category. The populations of
these two race categories were allocated to the standard single race categories
by age, gender and county. This allocation was based on the proportional distribution
of the population of the standard single race categories within each of these age,
gender, county groups.
POPULATION DATA FOR SELECTED AGE GROUPS: For inter-census
years, ORS provides estimated population data for South Carolina by age for five-year
age groups. It is assumed that the population within each of these age categories
is distributed uniformly through out the age interval. Based on this assumption,
the population for females 14-17, 15-17 and 18-19 years is derived, consecutively,
as follows - (20% of the female population 10-14 years plus 60% of the female population
15-19 years), (60% of the female population 15-19), and (40% of the female population
15-19). Pregnancy data for these teenagers are published annually in the South
Carolina Vital and Morbidity Statistics reports and also in the South
Carolina Teen Pregnancy Data Book(s).
In order to provide population data derived in a consistent manner over time, the
2000 population counts for these age groups are determined in like manner. These
population estimates, rounded to the nearest 10, and the pregnancy
rates are the same as provided in the 'Teen Pregnancy' Section of the South Carolina
Vital and Morbidity Statistics and the South Carolina Teen Pregnancy Data Book(s).
DATA LIMITATIONS: Resident abortion data are limited to
abortions that occur in South Carolina, North Carolina or Georgia to South Carolina
residents. Abortions occurring elsewhere to South Carolina residents are not included
in these data. Fetal deaths, which do not meet certain (see definitions) criteria
are excluded. Due to these limitations pregnancy data are reported as "estimated".
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