Vitalnet Health Statistics - Glossary

Apgar score - A summary measure of the condition of the infant based on heart rate, respiratory effort, muscle tone, reflex irritability, and color. Each factor is given a score of 0, 1, or 2; the sum of these five values is the Apgar score, ranging from 0 to 10.

Area set - One or more areas combined.

ASCII file - A text file, with only alphabetical, numerical, and punctuation characters, like you would see in normal text. Vitalnet can produce output in ASCII format.

Bar graphs - A section of a Vitalnet table. Gives a useful graphical representation of the data. May be omitted from the output table.

Birth rate - Births per 1,000 female or total population.

Birth weight - The weight of an infant at delivery, expressed in grams.

CDC - Centers for Disease Control and Prevention. US federal health agency.

Cell - A space for a single numerical result in a table, at a row-column intersection.

Cell suppression - An asterisk "*" is placed in cells with fewer deaths than a limit set by the user. Row / column totals with exactly one suppressed cell in the row / column are also suppressed. If more than one cell in the row / column is suppressed, the row / column total is displayed.

Cesarean rate - Number of cesareans / number of births.

Cesarean rate - primary - FC / (FC + FV). Numerator is number of first-time cesarean deliveries (FC). Denominator is number of first-time cesarean deliveries (FC) plus number of first-time vaginal deliveries (FV).

Cesarean rate - repeat - RC / (RC + VA). Numerator is number of repeat cesarean deliveries (RC). Denominator is number of repeat cesarean deliveries (RC) plus number of vaginal deliveries after previous cesarean (VA).

CNM - Certified Nurse Midwife (birth attendant category)

Columns - Vertical groupings of data in a Vitalnet table, such as a column for each race group.

Confidence interval (confidence limits) - A range of values within which the true value of a variable is thought to lie, with a specified level of confidence. For a result of 23.5, a confidence interval might be (23.1-23.9). The smaller the interval, the more reliable the result. If the 95% confidence intervals do not overlap, there is a statistically significant difference. Vitalnet uses several methods to calculate confidence intervals. The output table documents which method was used.

Confidence level - The likelihood that the true value of a variable is within a confidence interval. For example, for confidence intervals at the 95% level, we are statistically 95% certain that the actual value of the variable is within the interval.

CSV format - Also called comma-separated-value format. A type of computer output that is readily imported into other software, especially spreadsheet software. Each output item is separated by a comma from surrounding items, and each output text item is surrounded by "double quotes". Vitalnet produces CSV output. A comma-separated-value file has "csv" extension.

Data mining - Finding unexpected relationships in a data set. Similar to exploratory data analysis. Vitalnet is excellent at data mining. Of course, keep in mind that the more you look, the more unusual events you will find, just by chance.

Data warehouse - Software system, such as Vitalnet, making large complex databases readily available for querying and analysis.

dBASE III format - A widely used file format derived from the database software of the same name. Files in this format may be readily imported into almost any data analysis, graphing, mapping, or other presentation software. Has dbf extension. Suppressed cells are represented as the number "-1". Vitalnet produces dBASE III output.

DO - Doctor of Osteopathy (birth attendant category)

Denominator - The number on the bottom of a fraction. Population data are often referred to as "denominator data", as they are used as denominators to calculate population-based rates.

Export - Produce output that can be read into other computer programs. Vitalnet produces ASCII text, comma-separated-value (csv extension), HTML (htm extension), and dBASE III (dbf extension) files for export.

Filter variable - A variable solely used to filter which records are included in the output. For example, for a single table with race rows and sex columns, age is a filter variable.

Footer - Last part of a Vitalnet table. Lists other details of the analysis, such as the date and time produced, and the data sources. Each table is assigned a unique ID, listed in the footer, to assist you in keeping track of and organizing analyses.

General fertility rate - Total live births (to all women) per 1,000 women age 15-44 in a given year.

Gestational age - Number of completed weeks elapsed between the first day of the last normal menstrual period and the date of delivery. Gestational age is expressed in completed weeks.

General fertility rate - Live births per 1,000 women age 15-44 in a given year.

Header - First part of a Vitalnet table. Lists basic parameters you selected to define the table, such as years analyzed.

High birth weight - A birth weight 4,000 grams or greater.

High birth weight percent - Percent of births with birth weight 4,000 grams or greater.

HSA - Health Service Area. Groupings of California counties. There are 14 HSA's.

Import - Read information into a computer program. ASCII text, CSV files, HTML, and dBASE III files from Vitalnet are easily imported into word processing, spreadsheet, data analysis, mapping, graphing, and other presentation software programs.

Infant - An individual less than one year of age.

Infant death - Death of a liveborn infant from the moment of birth to the end of the first year of life.

Intrauterine growth retardation - Birth weight in the lowest decile of birth weight for gestational age. An alternative definition is birth weight less than 2,500 grams (low birth weight) in a full-term infant (born at or after 37 weeks gestation).

Kessner adequate percent - Numerator is number of births with adequate Kessner index. Denominator is number of births with known Kessner index (unknown Kessner scores are not included in denominator). This is a measure of the adequacy of prenatal care. A higher Kessner adequate percent for a population indicates better prenatal care.

Kessner index - Method of categorizing adequacy of prenatal care, based on month of pregnancy care started, number of visits, and length of gestation. This takes both amount and start of prenatal care into account, and adjusts for the fact that women with short gestations have less time in which to make prenatal care visits.

Least-squares - A standard method for fitting the best straight line to a set of points. Produces a 1 -intercept and a slope defining the least-squares line.

Live birth order - Live birth order is the number of children born alive to a mother, including the current baby. If the mother has three previous live births, the live birth order for the next birth is four. Another example: If the mother has one previous live birth, and has twins this time, the live birth order for the first twin is two, and is three for the second twin.

Low birth weight - A birth weight less than 2,500 grams (5 pounds, 9 ounces).

Low birth weight percent - Percent of births with birth weight less than 2,500 grams (5 pounds, 9 ounces).

MD - Doctor of Medicine (Physician) (birth attendant category)

Multiple age groups - One age group for each row or column of a table. Example: Birth-19, 20-39, 40-59, 60-99+.

NCHS - National Center for Health Statistics. US health statistics agency. Part of the CDC.

Neonatal death - Death of a liveborn infant within the first 27 days, 23 hours, and 59 minutes of life.

Neonatal death rate - Numerator = neonatal deaths x 1000. Denominator = number of liveborn infants.

Neonatal period - Period from birth through the first 27 days, 23 hours, and 59 minutes of life.

Neonate - A newborn infant during the first 27 days, 23 hours, and 59 minutes of life.

Perinatal period - Period from the 20th completed week of gestation (140 days) through the first 27 days, 23 hours, and 59 minutes of life.

Place of occurrence - The geographic location where a birth occurred.

Place of occurrence birth data - Data compiled by the location where the birth occurred, without regard to the place of residence of the mother.

Place of residence - The geographic location where a birth occurred.

Plurality - Number in a birth, such as twins or triplets.

Population - The number of people living in an area.

Postneonatal - Period between 28 days and one year of age.

Post term birth - Birth after the 41st week of gestation. Birth during or after the 42nd week of gestation.

Preterm birth - Birth occurring before the 38th week of gestation. Birth occurring during or before the 37th week of gestation.

Primary Statistic - The basic type of numerical result displayed in a table, chart, or map. For example, birth rate.

Rows - Horizontal lines in a Vitalnet table, such as a row for each race group.

Row sort settings - Vitalnet rows may be sorted in ascending or descending order.

Set - A combination of one or more things. For example, several areas may be combined into an area set.

Single age group - Only one age group (30-49, for example) is selected. A single age group is used for tables that do not have age columns or age rows.

Statistic - See "Primary Statistic".

Table - A set of results produced by Vitalnet. A table has several parts:

1. Header - lists basic analysis settings
2. Data section - numerical results
3. Horizontal bar graphs - graphical representation of the data
4. Footer - lists other analysis settings

Term birth - Birth during the four week period after the 37th week of gestation and before the 42nd week of gestation. Birth during the 38th through 41st week of gestation.

UNIX - A widely used computer operating system. Vitalnet can run on UNIX, either remotely, locally, or by client-server.

Unknown Values - Unknowns are automatically inserted into a Vitalnet table. For example, a separate row (or column) for unknown race. The rate is assigned as zero for an unknown category, since there is no population denominator to use. Some fields, such as sex for certain data sets, are never unknown, so unknowns are left off the table. When, such as for age-adjusted rates, the unknown variable (age) is different from the rows or columns, the number of unknowns for age is shown below the table.

Very low birth weight - A birth weight less than 1,500 grams (3 pounds, 5 ounces).

Very low birth weight percent - Percent of births with birth weight less than 1,500 grams (3 pounds, 5 ounces).

Windows - A widely used set of PC operating systems, including Windows 3.1, 95, 98, NT, 2000, and XP. Vitalnet will run under any version of Windows.

World Wide Web (WWW) - A widely used part of the internet that may be easily accessed with a web browser. Vitalnet runs on the WWW.