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Appendix B: Guide to Sources

National Center for Education Statistics (NCES) Data Sources

Beginning Postsecondary Students Longitudinal Study (BPS)

The Beginning Postsecondary Students Longitudinal Study (BPS) provides information on persistence, progress, and attainment from initial time of entry into postsecondary education through completion and entry into the workforce. BPS includes traditional and nontraditional (e.g., older) students and is representative of all beginning students in postsecondary education in a given year. Initially, these individuals are surveyed in the National Postsecondary Student Aid Study (NPSAS) during the year in which they first begin their postsecondary education. These same students are surveyed again 2 and 5 years later through BPS. By starting with a cohort that has already entered postsecondary education and following it for 6 years, BPS can determine to what extent students who start postsecondary education at various ages differ in their progress, persistence, and attainment. The first BPS was conducted in 1989–90, with follow-ups in 1992 and 1994. The second BPS was conducted in 1995–96, with follow-ups in 1998 and 2001. The third BPS was conducted in 2003–04, with follow-ups in 2006 and 2009. The fourth BPS is scheduled for 2012, with follow-ups in 2014 and 2017.

Further information on BPS may be obtained from

Aurora M. D'Amico
Sarah Crissey
Postsecondary, Adult, and Career Education Division
Postsecondary Longitudinal and Sample Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

Common Core of Data (CCD)

The Common Core of Data (CCD) is the Department of Education's primary database on public elementary and secondary education in the United States. It is a comprehensive, annual, national statistical database of all public elementary and secondary schools and school districts containing data designed to be comparable across all states. This database can be used to select samples for other NCES surveys and provide basic information and descriptive statistics on public elementary and secondary schools and schooling in general. Some of the CCD's component surveys date back to the 1930s. The integrated CCD was first implemented in the 1986 –87 school year.

The CCD collects statistical information annually from approximately 100,000 public elementary and secondary schools and approximately 18,000 public school districts (including supervisory unions and regional education service agencies) in the 50 states, the District of Columbia, Department of Defense dependents schools (DoDDS), and the outlying areas. Three categories of information are collected in the CCD survey: general descriptive information on schools and school districts; data on students and staff; and fiscal data. The general descriptive information includes name, address, phone number, and type of locale; the data on students and staff include selected demographic characteristics; and the fiscal data pertain to revenues and current expenditures.

The EDFacts data collection system is the primary collection tool for the CCD. NCES works collaboratively with the Department of Education's Performance Information Management Service to develop the CCD collection procedures and data definitions. Even though the CCD is a universe collection and thus not subject to sampling errors, nonsampling errors can occur. The two potential sources of nonsampling errors are nonresponse and inaccurate reporting. NCES attempts to minimize nonsampling errors through the use of annual training of SEA coordinators, extensive quality reviews, and survey editing procedures. In addition, each year, SEAs are given the opportunity to revise their state-level aggregates from the previous survey cycle.

Further information about the CCD and its survey components is available at

Early Childhood Longitudinal Study, Kindergarten Class of 1998–99 (ECLS-K)

The Early Childhood Longitudinal Study, Kindergarten Class of 1998–99 (ECLS-K) was designed to provide detailed information on children's early school experiences. The study began in the fall of 1998. A nationally representative sample of 21,260 children enrolled in 940 kindergarten programs during the 1998–99 school year was selected to participate in the ECLS-K. The children attended both public and private kindergartens, and full-day and part-day programs. The sample included children from different racial/ethnic and socioeconomic backgrounds and oversamples of Asian and Pacific Islander children and private school kindergartners. Base-year data were collected in the fall and spring of the kindergarten year. Data were collected again in the fall of 1st grade in 1999 (from a 30 percent subsample of schools) and the spring of 1st grade in 2000, and then in the spring of 3rd grade in 2002, the spring of 5th grade in 2004, and the spring of 8th grade in 2007.

From kindergarten to 5th grade, the ECLS-K included a direct child cognitive assessment that was administered one-on-one with each child in the study. The assessment used a computer-assisted personal interview (CAPI) approach and a two-stage adaptive testing methodology. In the 8th grade, a two-stage adaptive paper-and- pencil assessment was administered in small groups. At kindergarten and 1st grade, the assessment included three cognitive domains—reading, mathematics, and general knowledge. General knowledge was replaced by science at the 3rd, 5th, and 8th grades. Children's height and weight were measured at each data collection point, and a direct measure of children's psychomotor development was administered in the fall of the kindergarten year only. In addition to these measures, the ECLS-K collected information about children's social skills and academic achievement through teacher reports, and through student reports at the 3rd, 5th, and 8th grades.

A computer-assisted telephone interview with the children's parents/guardians was conducted at each data collection point. Parents/guardians were asked to provide key information about the ECLS-K sample children on subjects such as family demographics (e.g., family members, age, relation to child, race/ethnicity), family structure (e.g., household members and composition), parent involvement, home educational activities (e.g., reading to the child), child health, parental education and employment status, and the social skills and behaviors of their children.

Data on the schools that children attended and their classrooms were collected through self-administered questionnaires completed by school administrators and classroom teachers. Administrators provided information about the school population, programs, and policies. At the classroom level, data were collected from the teachers on the composition of the classroom, teaching practices, curriculum, and teacher qualifications and experience. In addition, special education teachers and related services staff provided reports on the services received by children with disabilities.

New data are being collected on a 2011 ECLS-K cohort. The first data collection began during the fall and spring of the 2010–11 school year. Follow-ups are planned for 2011–12 and in the spring from 2013–2016. This study will be similar to the older ECLS-K cohort, but it will provide insight into the more recent education policy changes, such as the No Child Left Behind Act, the increase in school choice, and the increase in English language learners.

Further information on the ECLS-K may be obtained from

Chris Chapman
Early Childhood, International, and Crosscutting Studies
Early Childhood and Household Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

Education Longitudinal Study of 2002 (ELS: 2002)

The Education Longitudinal Study of 2002 (ELS: 2002) is a longitudinal survey that is monitoring the transitions of a national probability sample of 10th-graders in public, Catholic, and other private schools. Survey waves follow both students and high school dropouts and monitor the transition of the cohort to postsecondary education, the labor force, and family formation.

In the base year of the study, of 1,220 eligible contacted schools, 750 participated, for an overall weighted school participation rate of approximately 68 percent (62 percent unweighted). Of 17,590 selected eligible students, 15,360 participated, for an overall weighted student response rate of approximately 87 percent. (School and student weighted response rates reflect use of the base weight [design weight] and do not include nonresponse adjustments.) Information for the study is obtained not just from students and their school records, but also from the students' parents, their teachers, their librarians, and the administrators of their schools.

The first follow-up was conducted in 2004, when most sample members were high school seniors. Base-year students who remained in their base schools were resurveyed and tested in mathematics, along with a freshening sample to make the study representative of spring 2004 high school seniors nationwide. The study collected comparable information from students who dropped out, students who transferred to a different school, and students who graduated early.

The second follow-up, completed in 2006, continued to follow the sample of students into postsecondary education, the workforce, or both. The next follow-up is scheduled for 2012.

Further information on ELS: 2002 may be obtained from

Elise Christopher
Elementary/Secondary and Libraries Studies Division
Elementary/Secondary Sample Survey Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

High School Longitudinal Study of 2009 (HSLS:09)

The High School Longitudinal Study of 2009 (HSLS:09) is a nationally representative, longitudinal study of more than 21,000 9th-grade students in 944 schools who will be followed through their secondary and postsecondary years. The study focuses on understanding students' trajectories from the beginning of high school into postsecondary education, the workforce, and beyond. Focused on but not limited to information on science, technology, engineering, and mathematics (STEM) education and careers, the HSLS:09 questionnaires are designed to provide data on mathematics and science education, the changing high school environment, and postsecondary education. This study features a new student assessment in algebra skills, reasoning, and problem solving and includes surveys of students, their parents, math and science teachers, and school administrators, as well as a new survey of school counselors.

The HSLS:09 student questionnaire includes interest and motivation items for measuring key factors predicting choice of postsecondary paths, including majors and eventual careers. This study will explore the roles of different factors in the development of a student's commitment to attend college and then to take the steps necessary to succeed in college (the right courses, courses in specific sequences, etc.). Questionnaires in this study will ask more questions of students and parents regarding reasons for selecting specific colleges (e.g., academic programs, financial aid and access prices, and campus environment). It will also look at levels of misinformation that may complicate postsecondary decisions.

HSLS:09 will be able to survey respondents during the critical junior and senior years regarding applications, acceptances, and rejections at colleges. A short computer- administered questionnaire will procure information on college acceptances and actual choices. In past longitudinal studies, this activity has been delayed to later follow-ups (2 years after high school).

Public-use HSLS data were used for report indicators when possible so that a wider audience could replicate the results. Restricted-use HSLS data were used for indicators that were based on variables or samples that could not be analyzed using the public-use file.

Further information on HSLS:09 may be obtained from

Laura LoGerfo
Project Officer for High School Longitudinal Study of
Secondary Longitudinal & Transcript Studies-ESLSD
1990 K Street NW
Washington, DC 20006

High School Transcript Study (HSTS)

High school transcript studies have been conducted by NCES as part of the Longitudinal Studies Program and the National Assessment of Educational Progress (NAEP) High School Transcript Studies (HSTS) program since 1982. Each transcript study is associated with a major NCES data collection. For example, the first NCES- sponsored transcript study was associated with the High School and Beyond (HS&B) first follow-up survey in 1982. The National Assessment of Education Progress (NAEP) collected transcript data in 1987, 1990, 1994, 1998, 2000, 2005, and 2009.

NCES high school transcript studies collect information that is contained on the student high school record; this information includes courses taken while attending secondary school, information on credits earned, year and term a specific course was taken, and final grades. When available, information on class rank and standardized scores is also collected. Once collected, information such as course name, credits earned, and course grades is transcribed and standardized (e.g., credits and credit hours are standardized to a common metric) and can be linked back to the student's questionnaire or assessment data. For example, when transcript data are collected by NAEP, HSTS offers information on the relationship between student coursetaking patterns and grade 12 achievement data on NAEP assessments.

Transcripts include information that is considered to be the official and fixed record regarding student coursetaking behavior. This information is considered to be more accurate than student self-report information and can be used to examine coursetaking patterns of students and to predict future education outcomes.

The 2009 transcript study was conducted from late spring 2009 through January 2010, after the administration of NAEP. Transcripts were collected for 12th-grade students who graduated from high school by the end of the collection period. Most students also participated in the NAEP assessments earlier that same year.

Further information on NAEP high school transcript studies may be obtained from

Janis Brown
Assessment Division
Assessment Research, Development & Implementation
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

Integrated Postsecondary Education Data System (IPEDS)

The Integrated Postsecondary Education Data System (IPEDS) surveys approximately 6,800 postsecondary institutions, including universities and colleges, as well as institutions offering technical and vocational education beyond the high school level. IPEDS, which began in 1986, replaced the Higher Education General Information
Survey (HEGIS).

IPEDS consists of eight interrelated components that are collected over three collection periods (fall, winter, and spring) each year. These components obtain information on who provides postsecondary education (institutions), who participates in it and completes it (students), what programs are offered and what programs are completed, and both the human and financial resources involved in the provision of institutionally based postsecondary education. Until 2000, these components included institutional characteristics, fall enrollment, completions, salaries, finance, and fall staff. Beginning in 2000, data were collected in the fall for institutional characteristics and completions; in the winter for employees by assigned position (EAP), salaries, and fall staff; and in the spring for enrollment, student financial aid, finances, and graduation rates. With the winter 2005–06 survey, the employees by assigned position, fall staff, and salaries components were merged into the human resources component. In 2007–08, the enrollment component was broken into two separate components: 12-month enrollment (collected in the fall) and fall enrollment (collected in the spring).

IPEDS race/ethnicity data collection changed in 2008–09. The “Asian” race category is now separate from a “Native Hawaiian or Other Pacific Islander” category. Survey takers also have the option to identify themselves as being of “Two or more races.” To recognize that “Hispanic” refers to ethnicity, and not race, the new Hispanic category reads “Hispanics of any race.”

Researchers can use IPEDS to analyze information on (1) enrollments of undergraduates, first-time freshmen, and graduate and first-professional students by race/ethnicity and sex; (2) institutional revenue and expenditure patterns by source of income and type of expense; (3) completions (awards) by level of program, level of award, race/ ethnicity, and sex; (4) characteristics of postsecondary institutions, including tuition, room and board charges, and calendar systems; (5) status of career and technical education programs; and (6) other issues of interest.

Beginning in 1993, the IPEDS survey completion became mandatory for all postsecondary institutions with a Program Participation Agreement (PPA) with the Office of Postsecondary Education (OPE), U.S. Department of Education—that is, institutions that participate in or are eligible to participate in any federal student financial assistance program authorized by Title IV of the Higher Education Act of 1965, as amended (20 USC 1094, Section 487 [a][17] and 34 CFR 668.14[b][19]). Such programs include Pell Gants and Stafford Loans given to students at 4-year and higher, 2-but-less-than 4-year, and less than 2-year postsecondary institutions, including degree and non-degree granting institutions. For institutions not eligible to participate in Title IV programs, participation in the IPEDS is voluntary. Prior to 1993, only national-level estimates from a sample of institutions are available for private less-than-2-year institutions.

Further information on IPEDS may be obtained from

Jessica Shedd
Postsecondary, Adult, and Career Education Division
Postsecondary Institutional Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

National Assessment of Educational Progress (NAEP)

The National Assessment of Educational Progress (NAEP) is a series of cross-sectional studies initially implemented in 1969 to assess the educational achievement of U.S. students and monitor changes in those achievements. In the main national NAEP, a nationally representative sample of students is assessed at grades 4, 8, and 12 in various academic subjects.

The assessments are based on frameworks developed by the National Assessment Governing Board (NAGB). Items include both multiple-choice and constructed-response (requiring written answers) items. Results are reported in two ways: by average score and by achievement level. Average scores are reported for the nation, for participating states and jurisdictions, and for subgroups of the population. Percentages of students meeting certain achievement levels are also reported for these groups. The achievement levels, developed by NAGB, are at or above Basic, at or above Proficient, and at or above Advanced.

From 1990 until 2001, main NAEP was conducted for states and other jurisdictions that chose to participate. In 2002, under the provisions of the No Child Left Behind Act of 2001, all states began to participate in main NAEP and an aggregate of all state samples replaced the separate national sample.

Mathematics assessments were administered in 2000, 2003, 2005, 2007, 2009, and 2011. In 2005, NAGB called for the development of a new mathematics framework. The revisions made to the mathematics framework for the 2005 assessment were intended to reflect recent curricular emphases and better assess the specific objectives for students at each grade level.

The revised mathematics framework focuses on two dimensions: mathematical content and cognitive demand. By considering these two dimensions for each item in the assessment, the framework ensures that NAEP assesses an appropriate balance of content, as well as a variety of ways of knowing and doing mathematics.

For grades 4 and 8, comparisons over time can be made among the assessments prior to and after the implementation of the 2005 framework. The changes to the grade 12 assessment were too drastic to allow the results to be directly compared with previous years. The changes to the grade 12 assessment included adding more questions on algebra, data analysis, and probability to reflect changes in high school mathematics standards and coursework, as well as the merging of the measurement and geometry content areas. The reporting scale for grade 12 mathematics was changed from 0–500 to 0–300. For more information regarding the 2005 mathematics framework revisions, see

Reading assessments were administered in 2000, 2002, 2003, 2005, 2007, 2009, and 2011. In 2009, a new framework was developed for the 4th-, 8th-, and 12th-grade NAEP reading assessments.

Both a content alignment study and a reading trend or bridge study were conducted to determine if the “new” assessment was comparable to the “old” assessment. Overall, the results of the special analyses suggested that the old and new assessments were similar in terms of their item and scale characteristics and the results they produced for important demographic groups of students. Thus, it was determined that the results of the 2009 reading assessment could still be compared to those from earlier assessment years, thereby maintaining the trend lines first established in 1992. For more information regarding the 2009 reading framework revisions, see

Further information on NAEP may be obtained from

Sherran T. Osborne
Assessment Operations
Outreach & Information Dissemination
National Center for Education Statistics
1990 K Street, NW
Washington, DC 20006

National Household Education Surveys Program (NHES)

The National Household Education Surveys Program (NHES) is a data collection system that is designed to address a wide range of education-related issues. Surveys have been conducted in 1991, 1993, 1995, 1996, 1999, 2001, 2003, 2005, and 2007. Data collected for 2012 will be available in 2013. NHES targets specific populations for detailed data collection. It is intended to provide more detailed data on the topics and populations of interest than are collected through supplements to other household surveys.

NHES: 2007 fielded two surveys: the Parent and Family Involvement in Education, and School Readiness. For the surveys, interviews were completed with parents of 10,680 sampled children in kindergarten through grade 12, including 10,370 students enrolled in public or private schools and 310 homeschooled children.

Further information on NHES may be obtained from

Andrew Zukerberg
Early Childhood, International, and Crosscutting Studies
Early Childhood and Household Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006

National Postsecondary Student Aid Study (NPSAS)

The National Postsecondary Student Aid Study (NPSAS) is a comprehensive nationwide study of how students and their families pay for postsecondary education. It covers nationally representative samples of undergraduates, graduates, and first-professional students in the 50 states, the District of Columbia, and Puerto Rico, including students attending less-than-2-year institutions, community colleges, 4-year colleges, and major universities. Participants include students who do not receive aid as well as those who do receive financial aid. The data collected by NPSAS provide information on the cost of postsecondary education, the distribution of financial aid, and the characteristics of both aided and non-aided students and their families. Study results are used to help guide future federal policy regarding student financial aid.

The early NPSAS studies, which began during the 1986 –87 school year, were conducted every 3 years, but from the 1999–2000 study to the present, NPSAS has been conducted every 4 years. The next cycle of NPSAS is scheduled for the 2011–12 school year. In the most recent study, NPSAS:08, about 114,000 undergraduate students and 14,000 graduate students enrolled in postsecondary education during the 2007–08 school year were selected from more than 1,730 postsecondary institutions. NPSAS:08 included a new set of instrument items to obtain baseline measures of the awareness of two new federal grants introduced in 2006: the Academic Competitiveness Grant (ACG) and the National Science and Mathematics Access to Retain Talent (SMART) grant.

Further information on NPSAS may be obtained from

Aurora D'Amico
Tracy Hunt-White
Postsecondary, Adult, and Career Education Division
Postsecondary Sample Survey Studies Program
National Center for Education Statistics
1990 K Street NW
Washington, DC 20006


Other Governmental Agency Data Sources

Census Bureau

American Community Survey (ACS)

The Census Bureau introduced the American Community Survey (ACS) in 1996. Fully implemented in 2005, it provides a large monthly sample of demographic, socioeconomic, and housing data comparable in content to the Long Forms of the Decennial Census up to and including the 2000 long form. Aggregated over time, these data will serve as a replacement for the Long Form of the Decennial Census. The survey includes questions mandated by federal law, federal regulations, and court decisions.

Since 2005, the survey has been mailed to approximately250,000 addresses in the United States and Puerto Rico each month, or about 2.5 percent of the population annually. A larger proportion of addresses in small governmental units (e.g., American Indian reservations, small counties, and towns) also receive the survey. The monthly sample size is designed to approximate the ratio used in the 2000 Census, which requires more intensive distribution in these areas. The ACS covers the U.S. resident population, which includes the entire civilian, noninstitutionalized population; incarcerated persons; institutionalized persons; and the active duty military who are in the United States. In 2006, the ACS began interviewing residents in group quarter facilities. Institutionalized group quarters include adult and juvenile correctional facilities, nursing facilities, and other health care facilities. Noninstitutionalized group quarters include college and university housing, military barracks, and other noninstitutional facilities such as workers and religious group quarters and temporary shelters for the homeless.

National-level data from the ACS are available from 2000 onward. Annual results were available for areas with populations of 65,000 or more beginning in the summer of 2006; for areas with populations of 20,000 or more in the summer of 2008; and for all areas—down to the census tract level. This schedule is based on the time it will take to collect data from a sample size large enough to produce accurate results for different size geographic units.

Further information about the ACS is available at

Current Population Survey (CPS)
The Current Population Survey (CPS) is a monthly survey of about 60,000 households conducted by the U.S. Census Bureau for the Bureau of Labor Statistics. The CPS is the primary source of information of labor force statistics for the U.S. noninstitutionalized population (e.g., excludes military personnel and their families living on bases and inmates of institutions). In addition, supplemental questionnaires are used to provide further information about the U.S. population. Specifically, in October, detailed questions regarding school enrollment and school characteristics are asked. In March, detailed questions regarding income are asked.

The current sample design, introduced in July 2001, includes about 72,000 households. Each month about 58,900 of the 72,000 households are eligible for interview, and of those, 7 to 10 percent are not interviewed because of temporary absence or unavailability. Information is obtained each month from those in the household who are 15 years of age and older and demographic data are collected for children 0–14 years of age. Prior to July 2001, data were collected in the CPS from about 50,000 dwelling units. The samples are initially selected based on the decennial census files and are periodically updated to reflect new housing construction.

The estimation procedure employed for monthly CPS data involves inflating weighted sample results to independent estimates of characteristics of the civilian noninstitutional population in the United States by age, sex, and race. These independent estimates are based on statistics from decennial censuses; statistics on births, deaths, immigration, and emigration; and statistics on the population in the armed services. Generalized standard error tables are provided in the Current Population Reports; methods for deriving standard errors can be found within the CPS technical documentation at The CPS data are subject to both nonsampling and sampling errors.

Beginning in 2003, race/ethnicity questions expanded to include information on people of two or more races. Pacific Islander/Native Hawaiian data is collected separately from Asian data. The questions have also been worded to make it clear that self-reported data on race/ ethnicity should reflect the race/ethnicity with which the responder identifies, rather than what may be written in official documentation.

October Supplement
Each year, the Annual Social and Economic (ASEC) Supplement and October supplemental questionnaires contain questions of relevance to education policy. The ASEC Supplement, formerly known as the March CPS Supplement, is a primary source of detailed information on income and work experience in the United States. The October Supplement routinely gathers data on school enrollment, school characteristics, and educational attainment for elementary, secondary, and postsecondary education. Related data are also collected about preschooling and the general adult population. NCES funds additional items on education-related topics such as language proficiency, disabilities, computer use and access, student mobility, and private school tuition. Responses are collected for all household members age 3 and over.

Further information on CPS may be obtained from

Education and Social Stratification Branch
Population Division
Census Bureau
U.S. Department of Commerce
4600 Silver Hill Road
Washington, DC 20233

Centers for Disease Control and Prevention(CDC)

Youth Risk Behavior Surveillance System (YRBSS)
The Youth Risk Behavior Surveillance System (YRBSS) was created in 1991 to monitor six types of health-risk behaviors that lead to death and disability among young adults: tobacco use, alcohol and other drug use, physical inactivity, sexual risk behaviors, unhealthy diet behaviors, and behaviors that contribute to unintentional injuries and violence. Obesity and asthma among youth and young adults are also measured. Surveys are conducted every 2 years, usually in the spring semester.

The system includes a national school-based survey conducted by the Centers for Disease Control and Prevention (CDC), as well as state, territorial, tribal, and local surveys conducted by state, territorial, and local health and education agencies and tribal governments. Each survey takes one class period to complete, approximately 10 minutes to distribute materials and give directions and 35 minutes to record responses. Permission is obtained from parents before administering this anonymous, voluntary survey. States and local agencies can add or delete questions from the core questionnaire to meet their policy or programmatic needs.

Local, territorial, and jurisdictional data from YRBSS surveys are weighted to represent all public school students in grades 9 through 12 in the respective jurisdiction. National data are collected from a separate scientific sample of students and are representative of students from all 50 states and the District of Columbia. Sample size varies according to area, district, or school administering the survey. Methodological studies were conducted in 1991 and 1999 to assess the validity of the self-reported behaviors and personal information. Research indicates that student-reported data is just as credible as that gathered from adults.

Further information on the YRBSS may be obtained from

U.S. Department of Health and Human Service
Division of Adolescent and School Health
4770 Buford Highway, NE
Atlanta, GA 30341
(800) 232-4636

National Center for Health Statistics

National Health Interview Survey (NHIS)
The main objective of the NHIS is to monitor the health of the United States population through the collection and analysis of data on a broad range of health topics. A major strength of this survey lies in the ability to display these health characteristics by many demographic and socioeconomic characteristics.

The NHIS covers the civilian noninstitutionalized population residing in the United States at the time of the interview. The NHIS is a cross-sectional household interview survey. Sampling and interviewing are continuous throughout each year. The sampling plan follows a multistage area probability design that permits the representative sampling of households and noninstitutional group quarters (e.g., college dormitories). The sampling plan is redesigned after every decennial census. The current sampling plan was implemented in 2006. It has many similarities to the previous sampling plan, which was in place from 1995 to 2005. The first stage of the current sampling plan consists of a sample of 428 primary sampling units (PSU's) drawn from approximately 1,900 geographically defined PSU's that cover the 50 States and the District of Columbia. A PSU consists of a county, a small group of contiguous counties, or a metropolitan statistical area.

The revised NHIS questionnaire, implemented since 1997, has Core questions and Supplements. The Core questions remain largely unchanged from year to year and allow for trends analysis and for data from more than one year to be pooled to increase sample size for analytic purposes. The Core contains four major components: Household, Family, Sample Adult, and Sample Child.

The Household component collects limited demographic information on all of the individuals living in a particular house. The Family component verifies and collects additional demographic information on each member from each family in the house and collects data on topics including health status and limitations, injuries, healthcare access and utilization, health insurance, and income and assets. The Family Core component allows the NHIS to serve as a sampling frame for additional integrated surveys as needed.

Data are collected through a personal household interview conducted by interviewers employed and trained by the U.S. Bureau of the Census according to procedures specified by the NCHS.

Further information on the NHIS may be obtained from

Information Dissemination Staff National Center for Health Statistics Centers for Disease Control and Prevention
3311 Toledo Road, Room 5407
Hyattsville, MD 20782-2003
(800) 232-4636


Other Organization Sources

American College Testing Program ACT assessment

The ACT assessment is designed to measure educational development in the areas of English, mathematics, social studies, and natural sciences. The ACT assessment is taken by college-bound high school students and by all graduating seniors in Colorado and Illinois. The test results are used to predict how well students might perform in college.

Prior to the 1984–85 school year, national norms were based on a 10-percent sample of the students taking the test. Since then, national norms are based on the test scores of all students taking the test. Beginning with 1984–85, these norms have been based on the most recent ACT scores available from students scheduled to graduate in the spring of the year. Duplicate test records are no longer used to produce national figures.

Separate ACT standard scores are computed for English, mathematics, science reasoning, and, as of October 1989, reading. ACT standard scores are reported for each subject area on a scale from 1 to 36. In 2010, the national composite score (the simple average of the four ACT standard scores 21.0, with a standard deviation of 5.2. The tests emphasize reasoning, analysis, problem solving, and the integration of learning from various sources, as well as the application of these proficiencies to the kinds of tasks college students are expected to perform.

It should be noted that graduating students who take the ACT assessment are not necessarily representative of graduating students nationally. Students who live in the Midwest, Rocky Mountains, Plains, and South are overrepresented among ACT-tested students as compared to graduating students nationally. These students more often attend public colleges and universities, which require the ACT assessment more often than the SAT test.

Further information on the ACT may be obtained from

500 ACT Drive
P.O. Box 168
Iowa City, IA 52243

College Entrance Examination Board

Advanced Placement Exam (AP)
The Advanced Placement (AP) program is a curriculum sponsored by the College Board that offers high school students the opportunity to take college-level courses in a high school setting. A student taking an AP course in high school can earn college credit for participation by attaining a certain minimum score on the AP exam in that subject area.

The AP program offers courses in 34 subjects. Although nearly 60 percent of U.S. high schools in the United States offer AP courses, the College Board does not require students to take an AP course before taking an AP exam. AP exams are offered once a year in May. Most of the exams take 2 to 3 hours to complete. The scores for all AP exams range from 1 to 5, with 5 being the highest score. Over 90 percent of the nation's colleges and universities have an AP policy granting incoming students credit, placement, or both, for qualifying AP exam scores.

The Admissions Testing Program of the College Board is made up of a number of college admissions tests, including the Preliminary Scholastic Assessment Test (PSAT) and the Scholastic Assessment Test, now known as the SAT. High school students participate in the testing program as sophomores, juniors, or seniors—some more than once during these 3 years. If they have taken the tests more than once, only the most recent scores are tabulated. The PSAT and SAT report sub-scores in the areas of mathematics and verbal ability.

The SAT results are not representative of high school students or college-bound students nationally, since the sample is self-selected (i.e., taken by students who need the results to apply to a particular college or university). Public colleges in many states, particularly in the Midwest, parts of the South, and the West, require ACT scores rather than SAT scores. The proportion of students taking the SAT in these states is very low and is inappropriate for comparison. In recent years, more than 1.4 million high school students have taken the SAT examination annually. About 3 million students took the examination in 2010. The latest version of the SAT, which includes a writing component, was first administered in March 2005.

Further information on the AP and SAT can be obtained from

College Entrance Examination Board
45 Columbus Ave.
New York, NY 10023


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