Slide Presentation from the AHRQ 2008 Annual Conference
On September 10, 2008, Ernest Moy, Jim Battles, Bill Carroll, and Anne Elixhauser, made this presentation at the 2008 Annual Conference. Select to access the PowerPoint® presentation (835 KB; Plugin Software Help).
Medical Expenditure Panel Survey (MEPS): Survey Overview
- 1977 National Medical Care Expenditure Survey.
- 1987 National Medical Expenditure Survey.
- 1996 Medical Expenditure Panel Survey.
The Medical Expenditure Panel Survey, or MEPS as it is commonly called, is the third in a series of national probability surveys conducted by AHRQ on the financing and utilization of medical care in the United States.
The National Medical Care Expenditure Survey (NMCES) was conducted in 1977, and the National Medical Expenditure Survey (NMES) in 1987. The MEPS was initiated in 1996 and continues to be fielded annually.
Although the modes of data collection and instrument design have changed considerably over the last 20 years, every effort was made to maintain a core set of critical data elements to facilitate longitudinal analysis.
MEPS Survey Components
The MEPS has two major components:
- MEPS-HC—Household Component.
- MEPS-IC—Insurance Component.
1) MEPS-HC—a household survey of the civilian non-institutionalized population.
2) MEPS-IC—an independent survey of employers and unions. The sample for the MEPS-IC includes about 45,000 establishments drawn from a Census Bureau frame. The data supports national and state-level estimates for all 50 states. Data from the MEPS-IC is used to produce estimates of the supply and cost of private health insurance available to American workers.
MEPS-HC Purpose & Uses
- Estimates annual health care use, expenditures and insurance coverage, and tracks changes in these over time.
- Provides estimates of expenditures and sources of payment by selected demographic variables.
- Used for policy-related and behavioral research on the determinants of health care use, spending, and insurance coverage.
- Used in micro simulation models to analyze alternative health care delivery proposals.
MEPS is primarily designed to provide nationally representative data on the types of health care Americans use, how frequently they use them, how much is paid for the services and the sources of payments. It can also be used to track changes and trends over time in health care utilization, expenditures for health care services, and the types of health insurance coverage, or lack of coverage, that Americans have.
MEPS can provide estimates of expenditures and sources of payments by selected demographic variables. For example, in 2005 white persons spent, out-of-pocket, an average of $773 (median=$270) on health care, compared to $416 (median=$45) for black persons and $344 (median=$20) for Hispanic persons.
MEPS data have formed the basis for policy-related and behavioral research on the determinants of health care use, spending, and insurance coverage. The Federal government uses MEPS data to prepare national estimates of health care use and spending; private and public health insurance coverage; and the availability, cost, and scope of private health insurance benefits for the U.S. population and for subgroups of policy interest.
Researchers in government, the health care industry, think tanks, advocacy groups, and universities use MEPS data for microsimulation models analyzing alternative health care delivery proposals.
MEPS-HC Survey Design
- Sub-sample of respondents from the previous year's NHIS.
- Representative of the civilian non-institutionalized population of the U.S.
- Five in-person interviews over 2½-year period using Computer Assisted Personal Interviewing (CAPI).
- Interviews average 90 minutes with a range of one to four hours.
The MEPS sample is a sub-sample of respondents from the previous year's Nation Health Interview Survey (NHIS), sponsored by the National Center for Health Statistics (NCHS). The NHIS is based on a stratified multistage cluster sample design. In the first stage primary sampling units are selected and consist of counties or groups of counties. In the second stage area segments are selected within the PSUs, and finally, housing units are selected within the area segments. This design is representative of the civilian non-institutionalized population of the US; persons serving on active duty in the armed forces, in prison or in a long term health care facility are not part of the civilian non-institutionalized population.
The MEPS is implemented through 5 in-person interviews over a 2½-year period using Computer Assisted Personal Interviewing (CAPI) technology. Both person and family level data are collected. Interviews average 90 minutes and have a range of one to four hours, depending on the number of persons in the household and their health care utilization.
MEPS-HC Survey Design—Oversampling
- Oversampling improves the precision of estimates for specific subgroups.
- Blacks and Hispanics have been oversampled every year with an additional over sampling of blacks in 2004.
- Low income and Asians oversampled in 2002 and beyond.
Oversampling is a feature of the MEPS sample design, helping to increase the precision of estimates for some subgroups of interest. Sample weights ensure that population estimates are not distorted by a disproportionate contribution from oversampled subgroups.
The oversampling of Hispanic and Black households in the NHIS carries over to the MEPS. In the NHIS, Hispanic households were oversampled at a rate of roughly 2 to 1. That is, the probability of selecting a Hispanic household for participation in the NHIS was roughly twice that for households in the general population that were not oversampled. The oversampling rate for black households was roughly 1.5 to 1.
For 2002 and beyond the MEPS includes an oversample for low income and Asian persons. The 1997 MEPS included an oversample for several subgroups.
MEPS-HC Sample Sizes
MEPS Panel Design: Data Reference Periods
Screen shot of a bar chart showing time spans for Panels 8-11 and various rounds from Q1 2004 to Q4 2006.
Notes: Overlapping Panel Design
Each year a new panel is initiated which includes 5 Rounds of interviews covering 2 full calendar years.
Since not all interviews can be conducted on the same day, reference periods can vary in length from 2-6 months. The Round 1 reference period goes from January 1st to the day of the first interview. Subsequent interviews cover the time frame since the previous interview. The Round 5 reference period ends on December 31st.
Since response rates tend to decline over time, the yearly MEPS data files combine data from the second year of a panel with data from the first year of a new panel to maximize the response rate.
For each panel Rounds 1, 2, and part of 3 comprise year 1; and part of Round 3, Round 4, and Round 5 comprise year 2.
This cycle is repeated each year. Subsequent panels can be combined to produce more precise estimates, or compared to monitor changes in health care utilization and expenditures over time.
MEPS-HC Core Interview Content
- Charges and Payments.
- Health Status.
- Health Insurance.
At each interview MEPS-HC collects detailed data on:
- Demographic Characteristics—including age, race/ethnicity, sex, marital status and family relationships.
- Charges and Payments for health care services by payer source.
- Health Status—including overall physical and mental health status, and activity and functional limitations.
- Conditions—including a list of priority conditions.
- Utilization data for all hospital visits, including emergency room (ER), inpatient and outpatient visits, physician services, home health care, and prescribed medicines.
- Employment data for all persons 16+ including employment status and information about each job held such as hours worked, job tenure, wages, types of business and whether health insurance was offered, and if health insurance was available from the employer, whether or not the person elected coverage.
- Health Insurance—both private and public health insurance status throughout the reference period and for each month, who the policy holder is, and the source of coverage (employer sponsored or privately purchased). We also collect information about who is covered, whether or not the policy is through an health maintenance organization (HMO) and self or family coverage.
MEPS-HC Supplemental CAPI Sections
Sections asked in rounds 2 and 4:
- Access to care.
- Child preventive health.
- Satisfaction with health plans & providers.
Sections asked in rounds 3 and 5:
- Assets (round 5 only).
- Preventive Care.
- Priority conditions.
Supplemental sections are asked once a year and tend to focus on areas of policy interest.
Sections asked in rounds 2 and 4 are:
- Access to care—whether persons have a usual source of care, reasons for not having a usual source of care and difficulties in obtaining care, including language barriers.
- Child preventive health includes a series of questions about the amounts and types of preventive care a child may receive when going to see a health care provider. Questions vary depending on the age of the child. Other measures include Consumer Assessment of Health Plans (CAHPS®) measures on health care received in the last year, the Columbia Impairment Scale for measuring behavior and relationships, the Living with Illness Measure to quantify resistance to illness and health needs due to a condition, and questions to identify children with special health care needs.
- Satisfaction—with usual source of care, health plans, and choice of providers.
Sections asked in rounds 3 and 5 are:
- Assets—asked in round 5 only.
- Income—amounts and types of income.
- Preventive Care questions are asked for each person primarily about the receipt of preventive care or screening examinations. Questions vary by age and gender subgroups.
- Priority conditions—Unlike other MEPS condition data that is conditioned on the reference year, this information is asked in the framework of "Did a doctor or health professional ever tell you that you had (condition)?" The conditions enumerated in this section are not added to the condition roster. Conditions include Sore throat, Diabetes, Asthma, Hypertension, Heart Disease, Arthritis, Joint pain, Stroke, and Emphysema. These conditions were selected because (1) they are relatively prevalent and (2) generally accepted standards for appropriate clinical care have been developed.
MEPS-HC Supplemental Paper Questionnaires (SAQs)
Diabetes Care SAQ
- Given once a year to each person identified as having diabetes.
- Includes questions about diabetes related tests and managing diabetes.
- Given once a year to each adult 18 years old and older.
- Focus is on information that needs to be self reported such as self assessments, height/weight, opinions about health care issues and quality of care measures.
For persons identified as having diabetes, a self-administered paper-and-pencil diabetes specific questionnaire is administered once a year. Questions are asked about whether or not they received recommended treatment to monitor their condition, for example a dilated eye exam, foot exam, and A1c test.
Starting in 2000 an adult SAQ is fielded once a year for each adult in the household. This questionnaire collects information on quality of care, health status, and outcomes. The focus is on information that needs to be self reported such as self assessments, height /weight, opinions about health care issues, and items that may be of a sensitive nature. The Adult SAQ contains patient satisfaction and accountability measures from the Consumer Assessment of Health Plans (CAHPS®), the SF-12 physical and mental health assessment tool, and attitude items. In 2000-2003 the EuroQol 5 (EQ-5D) dimensions with visual scale was included in the SAQ. Starting in 2004 the K-6 Kessler mental health distress scale and Patient Health Questionnaire two item depression scale (PHQ-2) were added.
Types of MEPS-HC Files
- Full-year Files—calendar year data.
- Point-in-time Files—snap shot first part of year.
- MEPS/NHIS Link File.
- Longitudinal Data File.
- MEPS HC-036: 1996-2005 Pooled Estimation File.
A series of calendar year specific full-year public use files (PUFs) are produced annually. Each of these files include information from several rounds of data collection which together comprise a complete calendar year's worth of information. Full-year data files vary in structure depending on the nature of the file content. Files are produced at the person level, event level, condition level, and job level. These files all contain data from the second year of a continuing panel combined with the first year of a new panel. The person identifier (DUPERSID) remains the same for a person for their entire duration in the survey. All data for a particular person across all files can be linked using this variable.
In addition to full-year files, MEPS also releases point-in-time files which produce a snap-shot of what is going on at a fixed point-in-time (Round 3 of a 2nd year panel and Round 1 of a new panel). These files contain minimal data elements and are primarily intended to give analysts an early glimpse of what the full-year insurance estimates will likely be.
The MEPS/NHIS Link File contains a cross-walk that will allow data users to merge the MEPS Full-Year Population Characteristics public use data file with the NHIS person-level public use data files.
For MEPS Panels 1-8, longitudinal weight files that were released contained a limited number of variables that could be merged with data from two consecutive full-year consolidated files to create a longitudinal file for analysis. Beginning with Panel 9, AHRQ is replacing the longitudinal weight files with more complete and analytically useful panel-specific files that contain the variables from the consolidated full-year files.
The Pooled Estimation file contains the proper variance structure to use when making estimates from MEPS data that has been pooled over several years.
Levels of MEPS-HC Public Use Files
- Person Level—detailed person information.
- Event Level—detailed event level information.
- Condition Level—detailed condition information.
- Job Level—detailed job information.
Person level files—each record on the file represents a person and includes characteristics associated with that person, for example age, race, sex, health insurance status and health care expenditures.
There are 8 types of event files; hospital stays, emergency room, out-patient department, medical visits, home health, dental, prescribed medicines, and other medical expenditures; each record represents a unique provider event.
Condition file—each record represents a unique condition reported for a particular person by the household respondent. Each record includes characteristics associated with the condition, for example ICD-9 code and whether the condition was caused by an accident or injury.
Job file—each record represents a unique job held by a household respondent 16 and older and includes characteristics of the job such as wages, industry, and occupation.
For event, job and condition level files a person may be associated with one record, several records, or none at all. All of the MEPS files for a particular year are linkable to each other. Linking information is provided as part of the documentation for each public use data file.
MEPS-HC Caveats and Limitations
- Sample size limitations preclude some analyses.
- Typically, one respondent provides data for the entire household.
- Household respondents may not be able to report accurately certain types of information:
- Type of health plan.
- Detailed event information.
Even after pooling several years of MEPS data, sample size limitations and confidentiality restrictions make MEPS data unsuitable for certain types of analysis. For example, the MEPS data do not support research on rare conditions.
Also, all MEPS data is typically reported by 1 designated household respondent. Reporting detailed information on other household members can sometimes be problematic since respondents may not be able to report certain types of information.
MEPS-IC (Insurance Component)
- An independent survey of employers and unions not linked to the household survey.
- The sample contains information from about 45,000 establishments and supports national and state-level estimates for all 50 states.
- Employer-sponsored health insurance measures:
- Benefit and payment provisions.
To complement the data collected in the MEPS-HC, an independent survey of employers and unions is conducted each year to collect information about employer sponsored health insurance.
The approximately 45,000 establishments participating in the MEPS-IC are selected through 2 sampling frames:
- A Bureau of the Census list frame of private sector business establishments and The Census of Governments from the Bureau of the Census. Data from these two sampling frames are used to produce annual national and state estimates of the supply and cost of private health insurance available to American workers.
The purpose of the MEPS-IC is to measure:
- Availability—how many employees are offered health insurance.
- Enrollment—how many employees take-up any offered insurance.
- Benefit and payment provisions—services covered and copays or deductibles.
- Cost—to both employer and employee.
- Since IC data is collected under Census Bureau Authority, public use data is limited to tables posted on the MEPS Web site.
Screen shot of MEPS Web page
The MEPS Web site is at http://meps.ahrq.gov/mepsweb/.
Besides being the primary source of MEPS public use data files, the Web site contains useful background information on the MEPS, electronic versions of publications, information about the onsite data center, copies of survey instruments, and MEPS-net—an interactive query tool
The Web site also allows users to subscribe to mailing lists to receive e-mail notifications of new data products and publications, and to participate in a moderated discussion forum designed to facilitate the free exchange of ideas and information about MEPS. Currently 464 data users have joined the discussion forum.
- Statistical Briefs: Easy-to-read, concise graphical summaries of MEPS data.
- Research Findings and Highlights: Tables and summaries of descriptive statistics.
- Methodology Reports: Detailed information on MEPS sample design and survey methods.
- Chartbooks: Policy-sensitive topics in an accessible question-and-answer format.
- Working Papers: Preliminary analyses of methodological and technical issues by AHRQ staff.
- Research in Action: Analyses using research results from AHRQ-sponsored studies, including MEPS data.
Note: All MEPS publications are available on the MEPS Web site in both PDF and HTML format.
AHRQ Data Center (ADC)
- Provides researchers access to non-public use MEPS data (except directly identifiable information).
- Mode of data analysis:
- On secure LAN at AHRQ.
- Task order agreement with data contractor.
- Combinations of both.
This information applies only to the AHRQ Data Center and does not apply to the Census Bureau Research Data Center (RDC). For reasons of confidentiality, some of the MEPS data collected cannot be publicly released. To allow outside researchers access to this data, AHRQ has established an on-site data center. It provides researchers with a secure physical space to access non public use MEPS data. Data Center researchers conduct their own analysis on stand alone PCs with minimal assistance from AHRQ staff. Researchers may enter into a task order agreement with our contractor for programming support.
Examples of Confidential Data Available for ADC Projects
- Linked MEPS-HC and Secondary Data.
- Full geo-coding for 1996, 1997 and 2000-2005. Federal Information Processing Standards (FIPS) codes for other years.
- Fully specified industry/occupation and condition codes.
- Selected State and MSA identifiers and estimation variables:
- 30 largest states and 10 largest MSAs.
The MEPS-HC data can be linked to secondary data such, as the Area Resource File. The 1996, 1997 and 2000 to 2004 data files have geo-codes down to the Census block-group level, and FIPS codes are available for other years. Also available are fully specified industry and occupation codes, fully specified condition codes, and state and MSA identifiers and estimation variables for the 30 largest states and 10 largest MSAs.
Current as of February 2009
Medical Expenditure Panel Survey: Survey Overview. Slide Presentation from the AHRQ 2008 Annual Conference (Text Version). February 2009. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/about/annualmtg08/091008slides/MoyBattles.htm