Texas Health Data

Center for Health Statistics




Adjusted rate
A rate that has taken into account influences on a crude rate, such as differences in age composition of the population.

Age adjustment
Age adjustment is a summarizing procedure to make comparisons of populations with different age distributions. It is used to compare risks for two or more populations at one point in time or for one population at two or more points in time. Age-adjusted rates are computed by the direct method by applying age-specific rates in a population of interest to a standardized age distribution, to eliminate differences in observed rates that result from age differences in population composition. The standard for age-adjusting death rates and estimates from surveys for most indicators in public health surveillance is the projected year 2000 U.S. resident population. Age-adjusted rates should be viewed as relative indexes rather than actual measures of risk. Age-adjusted estimates from any data source presented may differ from age-adjusted estimates based on the same data presented in other reports, if different age groups are used in the adjustment procedure.

Age-specific rate
Rate obtained for specific age groups (for example, age-specific fertility rate, death rate, marriage rate, illiteracy rate, school enrollment rate, etc).

An artifact is any representation in data, such as choice of methodology, or observational or data entry errors, that would cause a datum to misrepresent its true value.

Assessment is the regular and systematic collection, assembly, analysis, and dissemination of information about the health of a community. Public health assessment, policy development and assurance of access to quality health care are considered the three core functions of government in public health. (Institute of Medicine (1988) The Future of Public Health, National Academies Press.) See also Community Health Assessment.


Birth plurality
Classification of the number of children born from one pregnancy. This can be designated as single, twin, triplet, quadruplet, etc.

Birth rate
Birth rate is the number of live births per 1,000 persons (males and females) in the population.

Birth weight
The weight of an infant at delivery, recorded in pounds and ounces or in grams. Birth weights are classified into 3 groups: Normal, Low, and Very Low. Very Low birth weight babies are also included in the Low birth weight group. A Normal birth weight is defined as at least 5 pounds, 9 ounces (or 2,500 grams), Low—less than 5 pounds, 9 ounces (or 2,500 grams), and Very Low—less than 3 pounds, 5 ounces (or 1,500 grams).

Body mass index (BMI)
BMI is a measure that adjusts bodyweight for height. It is calculated as weight in kilograms divided by height in meters squared. Healthy weight for adults (20 years of age and over) is defined as a BMI of 18.5 to less than 25; overweight, as greater than or equal to a BMI of 25; and obesity, as greater than or equal to a BMI of 30.


There is philosophical debate about the meaning of 'cause,' but for a working definition in epidemiology, we can use a definition from Rothman and Greenland, Causation and Causal Inference in Epidemiology, "...a cause of a specific disease event [is] an antecedent event, condition, or characteristic that was necessary for the occurrence of the disease at the moment it occurred, given that other conditions are fixed.”

Cause of death
Any condition which leads to or contributes to death and is classifiable according to the tenth revision of The International Classification of Diseases (ICD-10).

Cesarean delivery
Extraction of the infant, placenta, and membranes through an incision in the maternal abdominal and uterine walls.

Childbearing years
The reproductive age span of women; conventionally defined as 15 through 44 years of age for the U.S. population.

Comparability ratio
A comparability ratio measures the level of agreement between ICD-9 and ICD-10 classification systems. NCHS calculated comparability ratios for 113 selected causes of death by using a double-coding exercise using 1996 death data. NCHS coded 1.8 million death certifications from 1996 first using ICD-9 and then using ICD-10. Based on that double-coding, NCHS has produced the set of Comparability Ratios for 113 Selected Causes of Death. Each ratio is an expression of the results of the comparison as a ratio of death for a cause of death by the later revision divided by the number of cause of death coded and classified by the earlier revision. To accurately portray trends that include both years 1980-1998 and 1999 on, the death counts or rates for the earlier years must be "comparability modified." This is accomplished by multiplying the earlier death count (or rate) by the comparability ratio for that cause of death. Use comparability-adjusted mortality counts and rates only when you need to display years 1998 and earlier together with years 1999 and later.

Confidence interval
The confidence interval may be thought of as the range of probable true values for a statistic. In general, as a population or sample size increases, the confidence interval gets smaller. Estimates with smaller confidence intervals are referred to as more "precise." Less precise estimates, such as those calculated from small numbers, tend to have wide confidence intervals. Typically, the 95% confidence interval (calculated as 1.96 times the standard error of a statistic) indicates the range of values within which the statistic would fall 95% of the time if the researcher were to calculate the statistic (e.g., a percentage or rate) from an infinite number of samples of the same size drawn from the same base population.

Congenital anomaly
Physical, physiological, or metabolic abnormality existing before or at birth, but not necessarily detectable at birth.

Chronic obstructive pulmonary diseases and allied conditions (replaced, as a leading cause, in ICD-10 by chronic lower respiratory diseases, codes J40 through J47).

A count is simply the number of health events, such as a death or a reported disease incident, that occurred within a specified time period.

Crude rate
The rate of any demographic or vital event that is based on an entire population.


The study of populations including their size, age-sex composition, distribution, density, growth, natality, mortality, nuptiality, migration, and any other characteristics which may affect these factors.


Educational attainment
Education is frequently used as the measure of socioeconomic status in presentations of health data. Educational attainment is generally measured as the highest level of school the respondent has completed or the highest credential received. In general, data on educational attainment are presented for ages beginning with 25 years, consistent with guidance given by the U.S. Bureau of the Census.

The classification of a population that shares common characteristics, such as, religion, traditions, culture, language, and tribal or national origin.

External cause of death
Death caused by Accidents and Adverse Effects (ICD-10 codes V01-X59,Y85-Y86), Suicide (U03,X60-X84,Y87.0), Homicide and Legal Intervention (U01-U02,X85-Y09,Y35,Y87.1,Y89.0), and other outside causes (Y10-Y34,Y36,Y40-Y84,Y87.2,Y88,Y89.1,Y89.9).


The actual reproductive performance of an individual, couple or a population.

Fetal death (stillbirth)
Death of a fetus while still in the uterus of its mother, regardless of the length of gestation. In Texas, fetal death registration is required for any fetus weighing 350 grams or more, or aged 20 weeks or more.


Gestation period
Number of completed weeks elapsed between the first day of the last normal menstrual period and the date of delivery.


Health indicator
Health indicators are measurable characteristics that describe the health of a population (such as life expectancy, mortality, disease incidence or prevalence, or other health states); determinants of health (such as health behaviors, health risk factors, physical environments, and socioeconomic environments); and health care access, cost, quality, and use. Depending on the measure, a health indicator may be defined for a specific population, place, political jurisdiction, or geographic area.

Health insurance status
Health insurance is broadly defined to include both public and private payors who cover medical expenditures incurred by a defined population in a variety of settings. Respondents were considered to be covered by private health insurance if they indicated private health insurance. Private health insurance includes managed care such as health maintenance organizations (HMOs). Persons were considered to be covered by public insurance if they reported Medicaid, a state-sponsored health program, the Children's Health Insurance Program (CHIP), Medicare, military health plan coverage, or other government-sponsored program coverage. The uninsured were persons who did not have coverage under private health insurance, a public health plan, or any other plan of unknown type.

Health Service Region (HSR)
Public health services are coordinated at the local level through the Health Service Region (HSR) offices. There are 11 Public Health Regions; however, for administrative purposes, there are 8 Health Service Region offices.

Hispanic origin
Hispanic or Latino origin includes persons of Mexican, Puerto Rican, Cuban, Central and South American, and other or unknown Latin American or Spanish origins, almost always self-reported.

HIV Treatment Cascade
A visual representation of the number and proportion of persons living with HIV who are engaged in the recommended stages of care from initial diagnosis to achieving viral suppression.

Death due to injury purposefully inflicted by other individuals (ICD-10 codes, U01-U02, X85-Y09, Y87.1), death from injuries resulting from legal intervention (homicide committed by law enforcement officers; ICD-10 codes, Y35, Y89.0).


The International Classification of Diseases, 10th edition. A system for classifying diseases and injuries developed by the World Health Organization and used worldwide to improve comparability of cause of death statistics reported from different countries. The tenth revision has been in use since January 1, 1999.

See Health indicator.

An individual less than one year of age.

Infant death
Death of an individual less than one year of age. Infant deaths are further classified as neonatal deaths and postneonatal deaths.

International Classification of Diseases (ICD)
The purpose of the ICD is to promote international comparability in the collection, classification, processing, and presentation of health statistics. The ICD is used to code and classify cause-of-death data. The ICD is developed collaboratively by the World Health Organization and 10 international centers, one of which is housed at the National Center for Health Statistics.

Intravenous Drug User(s) (IDU)
Persons who inject non-prescribed or recreational drugs into their bloodstream.




Live birth
The complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of the pregnancy, which after such separation, breathes or shows any other evidence of life such as beating of the heart, pulsation of umbilical cord, or definite movement of voluntary muscles, whether or not the umbilical cord has been cut or the placenta is attached.

List of 130 Selected Causes of Infant Death
NCHS list of selected causes of infant death for tabulating infant mortality statistics in order to provide a consistent grouping and ranking standard. Developed under the Tenth Revision of the International Classification of Diseases (ICD-10) by aggregating ICD-10 codes into 130 groups of selected causes of infant death that are of public health and medical importance. Used for the analysis of infant mortality and for ranking leading causes of infant death (see the List of 71 Rankable Causes of Infant Death). CDC/NCHS Instruction Manual: Part 9

List of 71 Rankable Causes of Infant Death
A subset of the 130 selected causes of death for infants; includes 71 groups of selected causes of infant death that are eligible to be ranked as leading causes of infant death.

Low birth weight
A birth weight less than 2,500 grams or less than 5 pounds, 9 ounces.


Malignant neoplasm
A tumor having the properties of invasion and metastasis.

Maternal death
The death of a woman resulting from pregnancy or childbearing, while pregnant or within 42 days of termination of pregnancy. ICD-10 codes O00 to O99 group these causes, often listed as "pregnancy, childbirth, and the puerperium."

Men who have sex with Men (MSM)
Male persons who engage in sexual activity with persons of the same sex, regardless of their sexual orientation.

Metropolitan Statistical Area (MSA)
One or more adjacent counties that have at least one urban core area of at least 50,000 population, plus adjacent territory that has a high degree of social and economic integration with the core as measured by commuting ties.

Mode of Transmission
The route by which an infectious organism (virus, bacteria, etc.) is transferred from one host (person) to another.

The occurrence of a disease in a population.

Death as a component of population change.


Birth as a component of population change.

An infant less than 28 days of age.


See Body Mass Index (BMI).


Persons Living with HIV (PLWH)
Persons who have previously been diagnosed with HIV infection and are not known to be deceased nor moved out of Texas at the end of a particular time period (typically the calendar year).

The total of all individuals in a given area.

An infant at least 28 days of age but less than one year of age.

Poverty status
Family income expressed as a percent of the poverty threshold. Each member of a family is classified according to the total income of the family. Unrelated individuals are classified according to their own income. Reported and imputed income levels are grouped into categories relative to the poverty threshold. The poverty threshold for each year is based on definitions originally developed by the Social Security Administration. These include a set of money income thresholds that vary by family size and composition. Families or individuals with income below their appropriate thresholds are classified as below the poverty threshold. These thresholds are updated annually by the U.S. Census Bureau to reflect changes in the Consumer Price Index for all urban consumers (CPI-U).

Preterm birth
Birth at less than 37 completed weeks of gestation.

Prevalence is the proportion of people in a population who have a specific disease at a point in time or a given time period. Prevalence estimates are often used to describe the burden of a disease for a given population.

Public Health Region (PHR)
Texas is legislatively divided into 11 Public Health Regions (PHR) for support of public health services at the local level. Each Texas county is assigned to one of 11 Public Health Regions. However, for administrative purposes, there are 8 regional public health offices.



In accordance with the Census Bureau and the U.S. Office of Management and Budget (OMB), racial categories in Texas Health Data "generally reflect a social definition of race recognized in this country and not an attempt to define race biologically, anthropologically, or genetically," (U.S. Census Bureau).

A categorization scheme established by the Texas State Data Center for continuity between the censuses of 1990, 2000, and 2010, the concept of race-ethnicity closely aligns with general perceptions of diversity within the Texas population during those decades. For statistical reporting, four major categories (White, Hispanic, Black, Other) represent the array of diversity of language, culture, national origin, and historical context within which individuals self identify. Persons of Hispanic origin are reported as Hispanic, regardless of other racial identification. Non-Hispanics in each of Census2000's 57 single and multiple race combinations get reassigned to one of the remaining three groups based upon divisions designed to maximize concordance with observed growth patterns across those decades.

The frequency of a demographic event in a specified period of time divided by the population at risk of the event.

The relation of one population subgroup to another subgroup, or to the whole population. The denominator of a ratio may or may not include the numerator. If the denominator includes the numerator, it is a special type of ratio known as a proportion.

The geographic area of the usual place of abode.

Residence data
Data compiled by the usual place of residence without regard to the geographic place where the event occurred. For births and fetal deaths, the mother's usual residence is used as the place of residence.


A method of race/ethnicity classification. This classification is derived from information provided by the parents for a birth certificate or by the informant who provided information for a death certificate.

Standardized rate
See adjusted rate.

Statistical significance
Used to evaluate the likelihood that chance variability may be considered an explanation for observed results. An appropriate mathematical test of statistical significance is calculated to determine the p value, which is the probability that the observed results may be due to chance alone. If the p value is less than an arbitrarily chosen value, commonly selected as 0.05, the findings are accepted as statistically significant at the 5 percent level. This indicates there is less than 5 percent probability that the observed results are due to chance alone.



Underlying cause of death
The disease or injury which initiated the train of morbid events leading directly to death, or the circumstances of the accident or violence which produced the fatal injury.


Vital event
An occurrence of birth, adoption, induced abortion, marriage, divorce or death, "together with any change in civil status which may occur during an individual's lifetime."

Vital statistics
Demographic data on abortions, births, deaths, fetal deaths, marriages and divorces.




Years of potential life lost (YPLL)
A measure of premature mortality for individuals who suffer early deaths. It is calculated as the sum of the years of life lost annually by persons who die before age 65.