Sources of Data on Disability

The Census Bureau

The Census Bureau (http://www.census.gov) collects much information on disability status. The long form questionnaire on the 1990 Decennial census contained questions about disability, including questions about work disability, the ability to go outside the home alone, and the ability to take care of personal needs. This data set is the only one that can provide direct estimates of disability at sub-state geographic levels. Following the 1990 census, a Content Reinterview Survey was conducted which provided more specific information on limitations.  Although the majority of the disability information is on the adult population, adult disability status can be used to establish need for and use of community resources. For example, if the unemployment status is higher for persons with disability in one community compared with another, it can be argued that increased resources should be applied to CSHCN in preparing them for transition to adulthood (e.g., job training, education, etc.).

The Census Bureau conducts three major surveys: the Decennial Census (see the Census module), Survey on Income and Program Participation and the Current Population Survey.

The Survey on Income and Program Participation (SIPP)

The SIPP (http://www.census.gov/hhes/sippdesc.html) is a national household survey that began in 1984. An extensive and reasonably consistent set of questions relating to disability was asked in 1990, 1991, 1992 and 1993 SIPP. This survey is the preferred source among Census Bureau surveys for disability information. The disadvantage to using this data is the small sample size that restricts the use of the data below the regional level.

The Current Population Survey

The Current Population Survey (CPS) (http://www.bls.census.gov/cps/cpsmain.htm) is conducted monthly and the disability questions focus only on work. The CPS identifies persons who are out of the labor force because of a disability and, in each March survey since 1980, identifies persons who have health problems which "prevent them from working or limits the kind or amount of work they can do." 

The National Center for Health Statistics

The National Center for Health Statistics (NCHS) of the U.S. Department of Health and Human Services (DHHS) is the primary Federal source of data on the physical health of the U.S. population. The NCHS collects and publishes data on a variety of health topics.

The National Health Interview Survey

The National Health Interview Survey (NHIS) (http://www.cdc.gov/nchswww/nchshome.htm) is one of the major surveys of the National Center for Health Statistics (NCHS), Centers for Disease Control and Prevention (http://www.cdc.gov/). Through NHIS, information concerning health of the civilian noninstitutionalized population is collected through household interviews conducted throughout the United States. Each year, the survey consists of a basic set of questions on health, socioeconomic, and demographic items as well as one or more special questionnaires to obtain more detailed information on major current health issues. The NHIS has operated continuously since 1957, and its sample survey design has been reevaluated and modified following each of the last three decennial censuses of the U.S. population.

The core questionnaire includes the following types of basic health and demographic questions: 

Demographic character of household members, including age, sex, race, education, and family income.

Disability days, including restricted-activity and bed disability days, and work- and school-loss days occurring during the 2-week period prior to the week of interview, as well as days spent in bed during the last 12 months.

Physician visits occurring during the same 2-week period, the interval since the last physician visit, and the number of visits during the last 12 months.

Acute and chronic conditions responsible for these days and visits.

Long-term limitation of activity resulting from chronic disease or impairment and the chronic conditions associated with the disability.

Short-stay hospitalization data, including the number of hospital episodes during the past year and the number of days for each stay.

Interviews are conducted each week throughout the year in a probability sample of households. The interviewing is performed by a permanent staff of interviewers employed by the U.S. Bureau of the Census. Data collected over the period of a year form the basis for the development of annual estimates of the health characteristics of the population and for the analysis of trends in those characteristics.

All adult members of the household 17 years of age and older who are at home at the time of the interview are invited to participate and to respond for themselves. Information for children and for adults not at home during the interview is provided by a responsible adult (19 years of age and over) residing in the household. Between 65 and 70 percent of the adults 17 years of age and over are self-respondents. Generally, a random subsample of adult household members is selected to self-respond to additional questions on current health topics that vary from year to year. Depending on the household size and the nature and extent of health conditions of household members, the length of the interview ranges between 20 and 90 minutes.

The households selected for interview each week are a probability sample representative of the target population. Data are collected from approximately 49,000 households including about 132,000 persons in a calendar year. Participation is voluntary; confidentiality of responses is guaranteed. The annual response rate of NHIS is over 95 percent of the eligible households in the sample.

National Health Interview Survey Supplements Relevant to Children's Health

NHIS 1990 Special Topics:

• Assistive Devices

NHIS 1991 Special Topics:

• Unintentional injuries
• Child health (includes childhood immunization; use of seat belts and safety seats; use of headgear and mouth guards during organized athletic activities; and, information on functional disabilities)
• Health promotion and disease prevention

NHIS 1992 Special Topics:

• Youth Risk Behavior Survey (youths 12-24)

NHIS 1993 Special Topics:

• Childhood immunizations (children <6 in each family with age-eligible children)
• Family resources (asked about all family members)

NHIS 1994 Special Topic:

• Survey on Disability (see below)

National Health Interview Survey on Disability

The National Disability Survey (http://www.cdc.gov/nchswww/products/catalogs/subject/nhis/diswrit.htm) is the first comprehensive survey of persons with disabilities, including children with disabilities. The survey was administered in two separate phases in 1994-95. Phase I included core NHIS items and a special set of items related to disability. This survey was intended to serve as a screen to identify persons with disabilities. Phase II was administered 6 to 9 months after Phase I to persons identified in Phase I as having a disability. The phase I survey was administered to 73,000 households with a total of 186,000 individuals.

Proposed data release dates are as follows:

Phase 1, 1994: July 1996

Phase 1, 1995: January 1998

Phase 2, 1994: February 1998

Phase 2, 1995: March 1998

Other Relevant Surveys Conducted by NCHS 

National Hospital Discharge Survey (NHDS)

The NHDS (http://www.cdc.gov/nchswww/products/catalogs/subject/nhds/nhds.htm) is a continuing nationwide sample survey that gathers information each year on patients (excluding newborn infants) discharged from a sample of non-Federal short-stay and specialty hospitals in the U.S. Unfortunately, because relatively few children are hospitalized each year and the NHDS does not oversample the child population, estimates are unreliable except for the most prevalent conditions.

Longitudinal Follow-up to the National Maternal and Infant Health Survey (1991)

This survey (http://www.cdc.gov/nchswww/products/catalogs/subject/mihs/lfnmihs.htm)was conducted among mothers who were initially identified in the 1988 National Maternal and Infant Health Survey (NMIHS). Information contained on this survey may be linked to the birth outcomes identified in the NMIHS survey. Extensive information was obtained about the mother and child, making this survey one of the most important resources for health information on children ages 3 to 4 years of age.