MEPS HC-0016E: 1997 Emergency Room Visits
Agency for Healthcare Research and Quality
Center for Financing, Access, and Cost Trends
540 Gaither Road
Rockville, MD 20850
(301) 427-1406
TABLE OF CONTENTS
A. Data Use
Agreement
B.
Background
1.0
Household Component
2.0
Medical Provider Component
3.0
Insurance Component
4.0
Nursing Home Component
5.0
Survey Management
C. Technical
and Programming Information
1.0
General Information
2.0 Data
File Information
2.1
Codebook Structure
2.2
Reserved Codes
2.3
Codebook Format
2.4
Variable Source and Naming Conventions
2.4.1
Variable-Source Crosswalk
2.4.2
Expenditure and Sources of Payment Variables
2.5 File
1 Contents
2.5.1
Survey Administration and ID Variables
2.5.1.1
Person Identifiers (DUID, PID, DUPERSID)
2.5.1.2
Record Identifiers (EVNTIDX, EVENTRN, ERHEVIDX, FFEEIDX, MPCDATA)
2.5.2
Characteristics of Emergency Room Visits
2.5.2.1
Visit Details (ERDATEYR-VSTRELCN)
2.5.2.2
Services, Procedures, and Prescription Medicines (LABTEST-DOCOUTF)
2.5.3
VA Facility (VAPLACE)
2.5.4
Condition and Procedure Codes (ERICD1X-ERICD3X, ERPRO1X) and Clinical
Classification Codes (ERCCC1X-ERCCC3X)
2.5.5
Record Count Variable (NUMCOND)
2.5.6
Flat Fee Variables
2.5.6.1
Definition of Flat Fee Payments
2.5.6.2
Flat Fee Type (FFERTYPE)
2.5.6.3
Caveats of Flat Fee Groups
2.5.7
Expenditure Data
2.5.7.1
Definition of Expenditures
2.5.7.2
Data Editing/Imputation Methodologies of Expenditure Variables
2.5.7.3
Emergency Room/Hospital Inpatient Stay Expenditures
2.5.7.4
Sources of Payment
2.5.7.5
Imputed Emergency Room Expenditure Variables
2.5.7.6
Rounding
2.5.7.7
Imputation Flags (IMPERFSF - IMPERCHG)
2.6
File 2 Contents: Pre-imputed Expenditure Variables
3.0
Sample Weights and Variance Estimation Variables (WTDPER97-VARPSU97)
3.1
Overview
3.2
Details on Person Weights Construction
3.2.1
MEPS Panel 1 Weight
3.2.2
MEPS Panel 2 Weight
3.2.3
The Final Weight for 1997
3.2.4
Coverage
4.0
Strategies for Estimation
4.1
Variables with Missing Values
4.2
Basic Estimates of Utilization, Expenditure and Sources of Payment
4.3
Estimates of the Number of Persons with Emergency Room Visit
4.4
Person-Based Ratio Estimates
4.4.1
Person-Based Ratio Estimates Relative to Persons with Emergency Room Use
4.4.2
Person-Based Ratio Estimates Relative to the Entire Population
4.5
Sampling Weights for Merging Previous Releases of MEPS Household Data with the
Emergency Room Visits File
4.6
Variance Estimation
5.0
Merging/Linking MEPS Data Files
5.1
Merging a Person-Level File to the Emergency Room Visit File
5.2
Linking the 1997 Emergency Room Visits File to the 1997 Medical Conditions File
and/or the 1997 Prescribed Medicines File
5.3
Limitations/Caveats of RXLK (the Prescribed Medicine Link File)
5.4
Limitations/Caveats of CLNK (the Medical Conditions Link File)
References
Attachment
1
D. Codebooks
(link to separate file)
E.
Variable-Source Crosswalk
A. Data Use Agreement
Individual identifiers have been removed from the
microdata contained in the files on this CD-ROM. Nevertheless, under sections
308 (d) and 903 (c) of the Public Health Service Act (42 U.S.C. 242m and 42
U.S.C. 299 a-1), data collected by the Agency for Healthcare Research and
Quality (AHRQ) and/or the National Center for Health Statistics (NCHS) may not
be used for any purpose other than for the purpose for which they were supplied;
any effort to determine the identity of any reported cases, is prohibited by
law.
Therefore in accordance with the above referenced Federal
statute, it is understood that:
- No one is to use the data in this data set in any way except for statistical reporting and
analysis.
If the identity of any person or establishment should be discovered inadvertently, then
(a) no use will be made of this knowledge, (b) the Director, Office of Management,
AHRQ will be advised of this incident, (c) the information that would identify any
individual or establishment will be safeguarded or destroyed, as requested by
AHRQ,
and (d) no one else will be informed of the discovered identity.
- No one will attempt to link this data set with individually identifiable records from any
data sets other than the Medical Expenditure Panel Survey or the National Health
Interview Survey.
By using these data you signify your agreement to comply
with the above-stated statutorily based requirements, with the knowledge that
deliberately making a false statement in any matter within the jurisdiction of
any department or agency of the Federal Government violates 18 U.S.C. 1001 and
is punishable by a fine of up to $10,000 or up to 5 years in prison.
The Agency for Healthcare Research and Quality requests
that users cite AHRQ and the Medical Expenditure Panel Survey as the data source
in any publications or research based upon these data.
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B. Background
This documentation describes one in a series of public use
files from the Medical Expenditure Panel Survey (MEPS). The survey provides a
new and extensive data set on the use of health services and health care in the
United States.
MEPS is conducted to provide nationally representative
estimates of health care use, expenditures, sources of payment, and insurance
coverage for the U.S. civilian noninstitutionalized population. MEPS also
includes a nationally representative survey of nursing homes and their
residents. MEPS is cosponsored by the Agency for Healthcare Research and Quality
(AHRQ) (formerly the Agency for Health Care Policy and Research (AHCPR)) and the
National Center for Health Statistics (NCHS).
MEPS comprises four component surveys: the Household
Component (HC), the Medical Provider Component (MPC), the Insurance Component
(IC), and the Nursing Home Component (NHC). The HC is the core survey, and it
forms the basis for the MPC sample and part of the IC sample. The separate NHC
sample supplements the other MEPS components. Together these surveys yield
comprehensive data that provide national estimates of the level and distribution
of health care use and expenditures, support health services research, and can
be used to assess health care policy implications.
MEPS is the third in a series of national probability
surveys conducted by AHRQ on the financing and use of medical care in the United
States. The National Medical Care Expenditure Survey (NMCES, also known as
NMES-1) was conducted in 1977. The National Medical Expenditure Survey (NMES-2)
was conducted in 1987. Beginning in 1996, MEPS continues this series with design
enhancements and efficiencies that provide a more current data resource to
capture the changing dynamics of the health care delivery and insurance system.
The design efficiencies incorporated into MEPS are in
accordance with the Department of Health and Human Services (DHHS) Survey
Integration Plan of June 1995, which focused on consolidating DHHS surveys,
achieving cost efficiencies, reducing respondent burden, and enhancing
analytical capacities. To accommodate these goals, new MEPS design features
include linkage with the National Health Interview Survey (NHIS), from which the
sampling frame for the MEPS HC is drawn, and continuous longitudinal data
collection for core survey components. The MEPS HC augments NHIS by selecting a
sample of NHIS respondents, collecting additional data on their health care
expenditures, and linking these data with additional information collected from
the respondents' medical providers, employers, and insurance providers.
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1.0 Household Component
The MEPS HC, a nationally representative survey of the
U.S. civilian noninstitutionalized population, collects medical expenditure data
at both the person and household levels. The HC collects detailed data on
demographic characteristics, health conditions, health status, use of medical
care services, charges and payments, access to care, satisfaction with care,
health insurance coverage, income, and employment.
The HC uses an overlapping panel design in which data are
collected through a preliminary contact followed by a series of five rounds of
interviews over a 2½-year period. Using computer-assisted personal interviewing
(CAPI) technology, data on medical expenditures and use for two calendar years
are collected from each household. This series of data collection rounds is
launched each subsequent year on a new sample of households to provide
overlapping panels of survey data and, when combined with other ongoing panels,
will provide continuous and current estimates of health care expenditures.
The sampling frame for the MEPS HC is drawn from
respondents to NHIS, conducted by NCHS. NHIS provides a nationally
representative sample of the U.S. civilian noninstitutionalized population, with
oversampling of Hispanics and blacks.
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2.0 Medical Provider Component
The MEPS MPC supplements and validates information on
medical care events reported in the MEPS HC by contacting medical providers and
pharmacies identified by household respondents. The MPC sample includes all
hospitals, hospital physicians, home health agencies, and pharmacies reported in
the HC. Also included in the MPC are all office-based physicians who:
- were identified by the household respondent as
providing care for HC respondents receiving Medicaid.
- were selected through a 75-percent sample of HC
households receiving care through an HMO (health maintenance organization)
or managed care plan.
- were selected through a 25-percent sample of the
remaining HC households.
Data are collected on medical and financial
characteristics of medical and pharmacy events reported by HC respondents,
including:
- Diagnoses coded according to ICD-9-CM (9th Revision,
International Classification of Diseases) and DSM-IV (Fourth Edition, Diagnostic and Statistical Manual of
Mental Disorders).
- Physician procedure codes classified by CPT-4 (Common
Procedure Terminology, Version 4).
- Inpatient stay codes classified by DRGs
(diagnosis-related groups).
- Prescriptions coded by national drug code (NDC),
medication name, strength, and quantity dispensed.
- Charges, payments, and the reasons for any difference
between charges and payments.
The MPC is conducted through telephone interviews and
mailed survey materials. In some instances, providers sent medical and billing
records which were abstracted into the survey instruments.
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3.0 Insurance Component
The MEPS IC collects data on health insurance plans
obtained through employers, unions, and other sources of private health
insurance. Data obtained in the IC include the number and types of private
insurance plans offered, benefits associated with these plans, premiums,
contributions by employers and employees, eligibility requirements, and employer
characteristics.
Establishments participating in the MEPS IC are selected
through four sampling frames:
- A list of employers or other insurance providers
identified by MEPS HC respondents who report having private health insurance
at the Round 1 interview.
- A Bureau of the Census list frame of private-sector
business establishments.
- The Census of Governments from Bureau of the Census.
- An Internal Revenue Service list of the
self-employed.
To provide an integrated picture of health insurance, data
collected from the first sampling frame (employers and insurance providers) are
linked back to data provided by the MEPS HC respondents. Data from the other
three sampling frames are collected to provide annual national and State
estimates of the supply of private health insurance available to American
workers and to evaluate policy issues pertaining to health insurance.
The MEPS IC is an annual survey. Data are collected from
the selected organizations through a prescreening telephone interview, a mailed
questionnaire, and a telephone followup for nonrespondents.
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4.0 Nursing Home Component
The 1996 MEPS NHC was a survey of nursing homes and
persons residing in or admitted to nursing homes at any time during calendar
year 1996. The NHC gathered information on the demographic characteristics,
residence history, health and functional status, use of services, use of
prescription medicines, and health care expenditures of nursing home residents.
Nursing home administrators and designated staff also provided information on
facility size, ownership, certification status, services provided, revenues and
expenses, and other facility characteristics. Data on the income, assets, family
relationships, and care-giving services for sampled nursing home residents were
obtained from next-of-kin or other knowledgeable persons in the community.
The 1996 MEPS NHC sample was selected using a two-stage
stratified probability design. In the first stage, facilities were selected; in
the second stage, facility residents were sampled, selecting both persons in
residence on January 1, 1996, and those admitted during the period January 1
through December 31.
The sample frame for facilities was derived from the
National Health Provider Inventory, which is updated periodically by NCHS. The
MEPS NHC data were collected in person in three rounds of data collection over a
1½-year period using the CAPI system. Community data were collected by
telephone using computer-assisted telephone interviewing (CATI) technology. At
the end of three rounds of data collection, the sample consisted of
approximately 815 responding facilities, 3,209 residents in the facility on
January 1, and 2,690 eligible residents admitted during 1996.
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5.0 Survey Management
MEPS data are collected under the authority of the Public
Health Service Act. They are edited and published in accordance with the
confidentiality provisions of this act and the Privacy Act. NCHS provides
consultation and technical assistance.
As soon as data collection and editing are completed, the
MEPS survey data are released to the public in staged releases of summary
reports and microdata files. Summary reports are released as printed documents
and electronic files. Microdata files are released on CD-ROM and/or as
electronic files.
Printed documents and CD-ROMs are available through the
AHRQ Publications Clearinghouse. Write or call:
AHRQ Publications Clearinghouse
Attn: (publication number)
P.O. Box 8547
Silver Spring, MD 20907
800/358-9295
410/381-3150 (callers outside the United States only)
888/586-6340 (toll-free TDD service; hearing impaired only)
Be sure to specify the AHRQ number of the document or
CD-ROM you are requesting. Selected electronic files are available from the
Internet on the MEPS web site: <http://www.meps.ahrq.gov/>.
Additional information on MEPS is available from the MEPS
project manager or the MEPS public use data manager at the Center for Cost and
Financing Studies, Agency for Healthcare Research and Quality.
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C. Technical and
Programming Information
1.0 General Information
This documentation describes one in a series of public use
event files from the 1997 Medical Expenditure Panel Survey (MEPS) Household (HC)
and Medical Provider Components (MPC). Released as an ASCII data file and SAS
transport file, this public use file provides detailed information on emergency
room visits for a nationally representative sample of the civilian
noninstitutionalized population of the United States and can be used to make
estimates of emergency room utilization and expenditures for calendar year 1997.
Each record on this file represents a unique emergency room visit reported by a
household respondent during the 1997 portion of Round 3 and Rounds 4 and 5 for
Panel 1, as well as Rounds 1, 2 and the 1997 portion of Round 3 for Panel 2
(i.e., the Rounds for the MEPS panels covering calendar year 1997). Emergency
room events reported in Round 3 and known to have begun after December 31, 1997
are not included on this file. In addition to expenditures related to this
event, each record contains household reported medical conditions and procedures
associated with the emergency room visit.
Data from this event file can be merged with other MEPS HC
data files, for the purpose of appending person characteristics such as
demographic or health insurance coverage to each emergency room visit
record.Counts of emergency room visits are based entirely on household reports.
Information from the MEPS MPC was used to supplement expenditure and payment
data reported by the household.
This file can be also used to construct summary variables
of expenditures, sources of payment, and related aspects of emergency room
visits. Aggregate annual person-level information on the use of emergency rooms
and other health services use in 1997 is provided on the MEPS 1997 Person Level
Use and Expenditure File where each record represents a MEPS sampled person.
The following documentation offers a brief overview of the
types and levels of data provided, the content and structure of the files and
the codebook, and programming information. It contains the following sections:
Data File Information
Sample Weights and Variance Estimation Variables
Merging MEPS Data Files
References
Codebook
Variable - Source Crosswalk
Any variables not found on this file but released on
previous MEPS Emergency Room Visits Files were excluded due to the fact that
they only contained missing data.
For more information on MEPS HC survey design see S.
Cohen, 1997; J. Cohen, 1997; and S. Cohen, 1996. For information on the MEPS MPC
design, see S. Cohen, 1998. A copy of the survey instrument
used to collect the information on this file is available on the MEPS web site
at the following address: http://www.meps.ahrq.gov
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2.0 Data File Information
This public use data release consists of two event-level
data files. File 1 contains characteristics associated with the emergency room
visit and imputed expenditure data. File 2 contains selected survey
administration and ID variables, as well as pre-imputed and un-imputed
expenditure data from both the Household and Medical Provider Components for all
emergency room visits on File 1. Please see Attachment 1 for definitions of
imputed, un-imputed, and pre-imputed expenditure variables.
Both Files1 and 2 of this public use data set contain
variables and frequency distributions for a total of 5975 emergency room visits
reported during the 1997 portion of Round 3 and Rounds 4 and 5 for Panel 1, as
well as Rounds 1, 2 and the 1997 portion of Round 3 for panel 2 (i.e., the
Rounds for the MEPS panels covering calendar year 1997) of the MEPS Household
Component. These files include emergency room visit records for all household
survey respondents who resided in eligible responding households and reported at
least one emergency room visit. Records where the emergency room visit was known
to have begun after December 31, 1997 are not included on this file. Of these
records, 5703 were associated with persons having positive person-level weights
(WTDPER97). The persons represented on this file had to meet either (a) or (b):
(a) Be classified as a key, in-scope person who
responded for his or her entire period of 1997 eligibility (i.e., persons with a
positive 1997 full-year person-level sampling weight (WTDPER97>0)), or
(b) Be classified as either an eligible, non-key
person or an eligible out-of-scope person who responded for his or her entire
period of 1997 eligibility, and belonged to a family (i.e., all persons with the
same value for a particular FAMID variable) in which all eligible family members
responded for their entire period of 1997 eligibility, and at least one family
member has a positive 1997 full-year person weight (i.e., eligible non-key or
eligible out-of-scope persons who are members of a family all of whose members
have a positive 1997 full-year MEPS family-level weight (WTFAM97>0)).
Please refer to Attachment 1 for definitions of keyness,
in-scope and eligibility. Persons with no emergency room visits for 1997 are not
included on this file (but are represented on MEPS person-level files).
Codebooks for both data files are included in Section D of this documentation.
For each variable on the file in the codebook, both weighted and unweighted
frequencies are provided.
Each emergency room visit record on File 1 includes the
following: date of the visit; whether or not person saw doctor; type of care
received; type of services (i.e. lab test, sonogram or ultrasound, x-rays etc.)
received, medicines prescribed during the visit; flat fee information; imputed
sources of payment; total payment and total charge; and a full-year person-level
weight.
File 2 of this public use data set is intended for
analysts who want to perform their own imputations to handle missing expenditure
data. This file contains one set of pre-imputed expenditure information from the
Medical Provider Component followed by one set of pre-imputed expenditure
information from the Household Component. Please see Attachment 1 for
definitions of pre-imputed and unimputed expenditure variables. Both sets of
expenditure data have been subject to minimal logical editing that accounted for
outliers, copayments or charges reported as total payments, and reimbursed
amounts that were reported as out-of-pocket payments. In addition, edits were
implemented to correct for misclassifications between Medicare and Medicaid and
between Medicare HMO's and private HMO's as payment sources. However, missing
data were not imputed.
Data from these files can be merged with the previously
released MEPS 1997 Full Year Population Characteristics File using the unique
person identifier, DUPERSID, to append person level information, such as
demographic or health insurance characteristics, to each record. Emergency room
events can also be linked to the MEPS 1997 Medical Conditions File (HC-018) and
the MEPS 1997 Prescribed Medicines File (HC-16A). The Appendix to MEPS 1997
Event Files (Appendix File) contains details on how to link MEPS data files.
Panel 1 cases (PANEL97 = 1 on the 1997 Full Year
Population Characteristics File) can also be linked back to the 96 MEPS HC
public use data files. However, the user should be aware that, at this time, no
weight is being provided to facilitate two year analysis of Panel 1 data.
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2.1 Codebook Structure
For each variable on these files, both weighted and
unweighted frequencies are provided. The codebook and data file sequence list
variables in the following order:
File 1
Unique person identifiers
Unique emergency room event identifiers
Other survey administration variables
Emergency room characteristic variables
ICD-9 condition and procedure codes
Clinical Classification Software codes
Imputed expenditure variables
Weight and variance estimation variables
File 2
Unique person identifiers
Unique emergency room event identifiers
Pre-imputed expenditure variables
Unimputed expenditure variables
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2.2 Reserved Codes
The following reserved code values are used:
Value Definition
-1 INAPPLICABLE Question was not asked due to skip
pattern.
-7 REFUSED Question was asked and respondent refused to
answer question.
-8 DK Question was asked and respondent did not know
answer.
-9 NOT ASCERTAINED Interviewer did not record the data.
Generally, values of -1,-7, -8, and -9 have not been
edited on this file. The values of -1 and -9 can be edited by analysts by
following the skip patterns in the questionnaire.
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2.3 Codebook Format
This codebook describes an ASCII data set (although the
data are also being provided in a SAS transport file). The following codebook
items are provided for each variable:
IDENTIFIER |
DESCRIPTION |
Name |
Variable name (maximum of 8
characters) |
Description |
Variable descriptor (maximum 40
characters) |
Format |
Number of bytes |
Type |
Type of data: numeric (indicated by
NUM) or character (indicated by CHAR) |
Start |
Beginning column position of
variable in record |
End |
Ending column position of variable
in record |
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2.4 Variable Source and
Naming Conventions
In general, variable names reflect the content of the
variable, with an 8 character limitation.
For questions asked in a specific round, the end digit in
the variable name reflects the round in which the question was asked. All
imputed/edited variables end with an "X."
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2.4.1 Variable-Source
Crosswalk
Variables contained on Files 1 and 2 were either derived
from the HC questionnaire itself, derived from the MPC data collection
instrument, derived from the CAPI, or assigned in sampling. The source of each
variable is identified in Section E, entitled "Variable - Source
Crosswalk." Sources for each variable are indicated in one of four ways in
the Source Column:
(1) variables which are derived from CAPI or assigned in
sampling are indicated as "CAPI derived" or "Assigned in
sampling," respectively;
(2) variables which come from one or more specific
questions have those questionnaire sections and question numbers indicated such
that,
ER - Emergency Room Questionnaire (HC)
FF - Flat Fee Questionnaire
(HC)
CP - Charge Payment
Questionnaire (HC)
HEF - Hospital Event Form (MPC);
(3) variables constructed from multiple questions using
complex algorithms are labeled "Constructed"; and
(4) variables which have been edited or imputed are so
indicated.
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2.4.2 Expenditure and
Sources of Payment Variables
Both pre-imputed and imputed versions of the expenditure
and sources of payment variables follow a standard naming convention and are 8
characters in length. Please note that pre-imputed means that a series of
logical edits have been performed on the variables, but missing data remain (see
File 2). The imputed versions incorporate the same edits but have also undergone
the imputation process to account for missing data (see File 1).
The pre-imputed expenditure variables on File 2 end with
an "H"if the data source was from the MEPS Household
Component. The unimputed expenditure variables end with a "M" if the
data source was the MEPS Medical Provider Component. All imputed variables on
File 1 end with an "X."
The total sum of payments, 12 sources of payment variables
and total charge variables are named consistently in the following way:
The first two characters indicate the type of event:
IP - inpatient stay
OB - office-based visit
ER - emergency room visit
OP - outpatient visit
HH - home health visit
DV - dental visit
OM - other medical equipment
RX - prescribed medicine
For expenditure variables on these files, the third
character indicates whether the expenditure is associated with the facility (F)
or the physician (D).
In the case of the sources of payment variables, the
fourth and fifth characters indicate:
SF - self or family
OF - other Federal Government
XP - sum
of payments
MR - Medicare
SL - State/local government
MD - Medicaid
WC - Worker's Compensation
PV - private insurance
OT - other insurance
VA - Veterans
OR - other private
CH - CHAMPUS/CHAMPVA
OU - other public
The sixth and seventh characters indicate the year (97)
and the last character of all imputed/edited variables is an "X."
For example, ERFSF97X is the edited/imputed amount paid by
self or family for the facility portion of the expenditure associated with an
emergency room visit.
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2.5 File 1 Contents
2.5.1 Survey Administration
and ID Variables
2.5.1.1 Person Identifiers (DUID,
PID, DUPERSID)
The dwelling unit ID (DUID) is a 5-digit random number
assigned after the case was sampled for MEPS. The 3-digit person number (PID)
uniquely identifies each person within the dwelling unit. The 8-character
variable DUPERSID uniquely identifies each person represented on the file and is
the combination of the variables DUID and PID. For detailed information on
dwelling units and families, please refer to the documentation for the MEPS 1997
Full Year Population Characteristics File or definitions listed in Attachment 1.
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2.5.1.2 Record Identifiers (EVNTIDX, EVENTRN, ERHEVIDX, FFEEIDX, MPCDATA)
EVNTIDX uniquely identifies each emergency room visit
(i.e. each record on the file) and is the variable required to link events to
data files containing details on conditions and/or prescribed medicines (MEPS
1997 Medical Conditions File and the MEPS 1997 Prescribed Medicines File,
respectively). For details on linking see the Appendix to the MEPS 1997 Event
Files.
EVENTRN indicates the round in which the emergency room
event was first reported.
ERHEVIDX is a constructed variable which identifies
emergency room visit records whose expenditures are included in the expenditures
for the associated hospital inpatient stay. This variable was constructed by
comparing date information for the reported hospital stay and all emergency room
visits for the same person. Please note that, where the emergency room visit is
associated with a hospital stay (and its expenditures and charges are included
with the hospital stay), the physician expenditures associated with the
emergency room visit are remain on the emergency room file.
FFEEIDX is a constructed variable which uniquely
identifies a flat fee group, that is, all events that were part of a flat fee
payment situation. For example, if a patient receives stitches in an emergency
room and comes back to have the stitches removed ten days later during an
outpatient visit, both visits are covered under one flat fee dollar amount.
These two events (the emergency room visit and the subsequent outpatient visit)
have the same value for FFEEIDX. Please note that FFEEIDX should be used to link
up all MEPS event files (excluding prescribed medicines) in order to determine
the full set of events that are part of a flat fee group.
MPCDATA is a constructed variable which indicates whether
or not MPC data were collected for the emergency room visit. While all emergency
room events are sampled into the Medical Provider Component, not all emergency
room event records have MPC data associated with them. This is dependent upon
the cooperation of the household respondent to provide permission forms to
contact the emergency room facility as well as the cooperation of the emergency
room facility to participate in the survey.
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2.5.2 Characteristics
of Emergency Room Visits
File 1 contains 21 variables describing emergency room
events reported by respondents in the Emergency Room section of the MEPS HC
questionnaire. The questionnaire contains specific probes for determining the
specific details about the emergency room event. Unless noted otherwise, the
following variables are provided as unedited.
2.5.2.1 Visit Details (ERDATEYR-VSTRELCN)
When a person reported having had a visit to the emergency
room, the date of the emergency room visit was reported (ERDATEYR, ERDATEMM,
ERDATEDD). The questionnaire determines
whether or not the person saw a medical doctor (SEEDOC).
The type of care the person received (VSTCTGRY) and whether or not the visit was
related to a specific condition (VSTRELCN) were also determined.
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2.5.2.2 Services, Procedures,
and Prescription Medicines (LABTEST-DOCOUTF)
Services received during the visit included whether or not
the person received lab tests (LABTEST), a sonogram or ultrasound (SONOGRAM),
x-rays (XRAYS), a mammogram (MAMMOG), an MRI or CAT scan (MRI), an
electrocardiogram (EKG), an electroencephalogram (EEG), a vaccination (RCVVAC),
anesthesia (ANESTH), or other diagnostic tests or exams (OTHSVCE). Whether or
not a surgical procedure was performed during the visit was asked (SURGPROC)
and, if so, the procedure name (SURGNAME) was also asked. The questionnaire
determined if a medicine was prescribed for the person during the emergency room
visit (MEDPRESC). See Section 5.2 for information on linking to the prescription
medicine events file. Finally, it was reported if the person saw any of the same
doctors or surgeons at their place of practice outside of the emergency room (DOCOUTF).
2.5.3 VA Facility (VAPLACE)
VAPLACE is a constructed variable that indicates whether
the provider worked at a VA facility. This variable only has valid data for
providers that were sampled into the Medical Provider Component. All other
providers are classified as unknown.
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2.5.4 Condition and Procedure Codes (ERICD1X-ERICD3X, ERPRO1X) and Clinical Classification Codes
(ERCCC1X-ERCCC3X)
Information on household reported medical conditions
and procedures associated with each emergency room visit are provided
on this file.
There are up to three condition codes (ERICD1X-ERICD3X) and one procedure
code (ERPRO1X) listed for each emergency room visit (99.2% of emergency
room visits
have 0-3 condition records linked). In order to obtain complete condition
information associated with an event, the analyst must link to the
MEPS 1997 Medical Conditions File. Details on how to link to the MEPS
1997 Medical
Conditions File are provided in the Appendix File. The
user should note that because of confidentiality restrictions, provider
reported
condition information is not publicly available.
The medical conditions and procedures reported by the
Household Component respondent were recorded by the interviewer as verbatim
text, which were then coded to fully-specified 1997 ICD-9-CM codes, including
medical conditions and V codes (see Health Care Financing Administration, 1980)
by professional coders. Although codes were verified and error rates did not
exceed 2.5 percent for any coder, analysts should not presume this level of
precision in the data; the ability of household respondents to report condition
data that can be coded accurately should not be assumed (see Cox and Cohen,
1985; Cox and Iachan, 1987; Edwards, et al, 1994; and Johnson and Sanchez,
1993). For detailed information on how conditions and procedures were coded,
please refer to the documentation on the MEPS1997 Medical Conditions File. For
frequencies of conditions by event type, please see the Appendix File.
The ICD-9-CM codes were aggregated into clinically
meaningful categories. These categories, included on the file as
ERCCC1X-ERCCC3X, were generated using Clinical Classification Software (formerly
known as Clinical Classifications for Health Care Policy Research (CCHPR)), (Elixhauser,
et al., 1998), which aggregates conditions and V-codes into 260 mutually
exclusive categories, most of which are clinically homogeneous.
In order to preserve respondent confidentiality, nearly
all of the condition codes provided on this file have been collapsed from
fully-specified codes to 3-digit code categories. The reported ICD-9-CM code
values were mapped to the appropriate clinical classification category prior to
being collapsed to the 3-digit categories. Details on this procedure are
outlined in the 1997 Medical Conditions File.
The condition codes (and clinical classification codes)
and procedure codes linked to each emergency room visit are sequenced in the
order in which the conditions were reported by the household respondent, which
was in chronological order of occurrence and not in order of importance or
severity. Analysts who use the MEPS 1997 Medical Conditions File in conjunction
with this emergency room visit file should note that the order of conditions on
this file is not identical to that on the Medical Conditions file.
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2.5.5 Record Count Variable (NUMCOND)
The variable NUMCOND indicates the total number of
condition records which can be linked from the MEPS 1997 Medical Conditions File
to each emergency room visit. For events where no condition records linked (NUMCOND=0),
the condition and procedure and clinical classification code variables all have
a value of -1 INAPPLICABLE. Similarly, for events without a linked second or
third condition record, the corresponding second or third condition, clinical
classification code and procedure code variables were set to -1 INAPPLICABLE.
In order to obtain complete condition information for
events with NUMCOND greater than 3 the analyst must link to the MEPS 1997
Medical Conditions File. Please see the Appendix File for details on linking
MEPS data files.
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2.5.6 Flat Fee Variables
2.5.6.1 Definition of
Flat Fee Payments
A flat fee is the fixed dollar amount a person is charged
for a package of health care services. Examples would be: obstetrician's fee
covering a normal delivery, as well as pre- and post-natal care; or a surgeon's
fee covering surgical procedure and post-surgical care. A flat fee group is the
set of medical services (i.e., events) that are covered under the same flat fee
payment situation. The flat fee groups represented on this file (and all of the
other MEPS 1997 event files) includes flat fee groups where at least one of the
health care events, as reported by the HC respondent, occurred during 1997. By
definition a flat fee group can span multiple years and/or event types (e.g.,
hospital stay, physician office visit), and a single person can have multiple
flat fee groups.
As noted earlier in the section on Record Identifiers
(Section 2.5.1.2), for a person, the variable FFEEIDX can be used to identify
all events that are part of the same flat fee group. It can be used to identify
such events because FFEEIDX is the same value on all MEPS 1997 Event Files
(excluding the MEPS 1997 Prescribed Medicines Files). For the emergency room
visits that are not part of a flat fee payment situation, the flat fee variables
described below are all set to -1 INAPPLICABLE .
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2.5.6.2 Flat Fee Type (FFERTYPE)
FFERTYPE indicates whether the 1997 emergency room visit
is the "stem" or "leaf" of a flat fee group. A stem (records
with FFERTYPE= 1) is the initial medical service (event) which is followed by
other medical events that are covered under the same flat fee payment. The leaf
of the flat fee group (records with FFERTYPE = 2) are those medical events that
are tied back to the initial medical event (the stem) in the flat fee group.
These "leaf" records have their expenditure variables set to zero.
2.5.6.3 Caveats of Flat Fee
Groups
There are 28 emergency room visits that are identified as
being part of a flat fee payment group.
In general, every flat fee group should have an initial
visit (stem) and at least one subsequent visit (leaf). There are some situations
where this is not true. For some flat fee groups, the initial visit reported
occurred in 1997 but the remaining visits that were part of this flat fee group
occurred in 1998. In this case, the 1997 flat fee group represented on this file
would consist of one event, the stem; the 1997 events that are part of this flat
fee group are not represented on the file. Similarly, the household respondent
may have reported a flat fee group where the initial visit began in 1996 but
subsequent visits occurred during 1997. In this case, the initial visit would
not be represented on the file. This 1997 flat fee group would then only consist
of one or more leaf records and no stem. Another reason for which a flat fee
group would not have a stem and a leaf record is that the stems or leaves could
have been reported as different event types. In a small number of cases, there
are flat fee groups that span various event types. The stem may have been
reported as one event type and the
leaves may have been reported as another event type. In
order to determine the different event types in a flat fee group , the analyst
must link all MEPS event files (excluding the prescribed medicines file) using
the variable FFEEIDX to create the complete flat fee group.
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2.5.7 Expenditure Data
2.5.7.1 Definition of
Expenditures
Expenditures on this file refer to what is paid for health
care services. More specifically, expenditures in MEPS are defined as the sum of
payments for care received for each emergency room visit, including
out-of-pocket payments and payments made by private insurance, Medicaid,
Medicare and other sources. The definition of expenditures used in MEPS differs
slightly from its predecessors: the 1987 NMES and 1977 NMCES surveys where
"charges" rather than sum of payments were used to measure
expenditures. This change was adopted because charges became a less appropriate
proxy for medical expenditures during the 1990's due to the increasingly common
practice of discounting. Although measuring expenditures as the sum of payments
incorporates discounts in the MEPS expenditure estimates, the estimates do not
incorporate any payment not directly tied to specific medical care visits, such
as bonuses or retrospective payment adjustments by third party payers. Another
general change from the two prior surveys is that charges associated with
uncollected liability, bad debt, and charitable care (unless provided by a
public clinic or hospital) are not counted as expenditures because there are no
payments associated with those classifications. While charge data are provided
on this file, analysts should use caution when working with this data because a
charge does not typically represent actual dollars exchanged for services or the
resource costs of those services; nor are they directly comparable to the
expenditures defined in the 1987 NMES. For details on expenditure definitions,
please reference the following, "Informing American Health Care
Policy" (Monheit et al., 1999).
Expenditure data related to emergency room visits are
broken out by facility and separately billing doctor expenditures. This file
contains five categories of expenditure variables per visit: basic hospital
emergency room facility expenses, expenses for doctors who billed separately
from the hospital for any emergency room services provided during emergency room
visit, total expenses, which is the sum of the facility and physician expenses;
facility total charge and physician total charge.
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2.5.7.2 Data Editing/Imputation Methodologies of Expenditure Variables
General Imputation Methodology
The expenditure data included on this file were derived
from both the MEPS Household (HC) and Medical Provider Component (MPC). The MPC
contacted medical providers identified by household respondents. The charge and
payment data from medical providers were used in the expenditure imputation
process to supplement missing household data. For all emergency room visits, MPC
data were used if complete; otherwise, HC data were used if complete. Missing
data for emergency room visits, where HC data were not complete and MPC data
were not collected or complete, were derived through the imputation process.
General Data Editing Methodology
Logical edits were used to resolve internal
inconsistencies and other problems in the HC and MPC survey-reported data. The
edits were designed to preserve partial payment data from households and
providers, and to identify actual and potential sources of payment for each
household-reported event. In general, these edits accounted for outliers,
co-payments or charges reported as total payments, and reimbursed amounts that
were reported as out-of-pocket payments. In addition, edits were implemented to
correct for mis-classifications between Medicare and Medicaid and between
Medicare HMO's and private HMO's as payment sources. These edits produced a
complete vector of expenditures for some events, and provided the starting point
for imputing missing expenditures in the remaining events.
General Hot-Deck Imputation Methodology
A weighted sequential hot-deck procedure was used to
impute missing expenditures as well as total charge. This procedure uses survey
data from respondents to replace missing data while taking into account the
respondents' weighted distribution in the imputation process. Classification
variables vary by event type in the hot-deck imputations, but total charge and
insurance coverage are key variables in all of the imputations. Separate
imputations were performed for nine categories of medical provider care:
inpatient hospital stays, outpatient hospital department visits, emergency room
visits, visits to physicians, visits to non-physician providers, dental
services, home health care by certified providers, home health care by paid
independents, and other medical expenses. After the imputations were finished,
visits to physician and non-physician providers were combined into a single
medical provider file. The two categories of home care also were combined into a
single home health file.
Capitation Imputation
The imputation process was also used to make expenditure
estimates at the event level for events that were paid on a capitated basis. The
capitation imputation procedure was designed as reasonable approach to complete
event level expenditures for respondents in managed care plans. This procedure
was conducted in two stages. First, HMO events reported in the MPC as covered by
capitation arrangements were imputed using similar HMO events paid on a
fee-for-service, with total charge as a key variable. Then this completed set of
MPC events was used as the donor pool for unmatched household-reported events
for sample persons in HMOs. By using this strategy, capitated HMO events were
imputed as if the provider were reimbursed from the HMO on a discounted
fee-for-service basis.
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Imputation Methodology for Emergency Room Visits
Facility expenditures for emergency room services were
developed in a sequence of logical edits and imputations. "Household"
edits were applied to sources and amounts of payment for all events reported by
HC respondents. "MPC" edits were applied to provider-reported sources
and amounts of payment for records matched to household-reported events. Both
sets of edits were used to correct obvious errors in the reporting of
expenditures. After the data from each source were edited, a decision was made
as to whether household- or MPC-reported information would be used in the final
editing and hot-deck imputations for missing expenditures.
The general rule was that MPC data would be used where a household reported
event corresponded to a MPC reported event (i.e., a matched event), since
providers usually have more complete and accurate data on sources and amounts of
payment than households.
One of the more important edits separated flat fee events
from simple events. This edit was necessary because groups of events covered by
a flat fee (i.e. a flat fee bundle) were edited and imputed separately from
individual events covered by a single charge (i.e., simple events). Most
emergency room events were imputed as simple events because hospital facility
charges are rarely bundled with other events. (See Section 2.5.7 for more
details on flat fee groups). However, some emergency room visits were treated as
free events because the respondent was admitted to a hospital through its
emergency room. In these cases, emergency room charges are included in the
charge for an inpatient hospital stay.
Logical edits also were used to sort each event into a
specific category for the imputations. Events with complete expenditures were
flagged as potential donors for the hot-deck imputations, while events with
missing expenditure data were assigned to various recipient categories. Each
event was assigned to a recipient category based on its pattern of missing data.
For example, an event with a known total charge but no expenditures information
was assigned to one category, while an event with a known total charge and some
expenditures information was assigned to a different category. Similarly, events
without a known total charge were assigned to various recipient categories based
on the amount of missing data.
The logical edits produced eight recipient categories in
which all events had a common pattern of missing data. Separate hot-deck
imputations were performed on events in each recipient category, and the donor
pool was restricted to events with complete expenditures from the MPC. The donor
pool restriction was used even though some unmatched events had complete
household-reported expenditures. These events were not allowed to donate
information to other events because the MPC data were considered to be more
reliable.
The donor pool included "free events" because,
in some instances, providers are not paid for their services. These events
represent charity care, bad debt, provider failure to bill, and third party
payer restrictions on reimbursement in certain circumstances. If free events
were excluded from the donor pool, total expenditures would be over-counted
because the cost of free care would be implicitly included in paid events and
explicitly included in events that should have been treated as free from
provider.
Expenditures for some emergency room visits are not shown
because the person was admitted to the hospital through the emergency room.
These emergency room events are not free, but the expenditures are included in
the inpatient stay expenditures. The variable ERHEVIDX can be used to
differentiate between free emergency room care and situations where the
emergency room charges have been included in the inpatient hospital charges.
Expenditures for services provided by separately billing
doctors in hospital settings were also edited and imputed. These expenditures
are shown separately from hospital facility charges for hospital inpatient,
outpatient, and emergency room care.
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Flat Fee Expenditures
The approach used to count expenditures for flat fees was
to place the expenditure on the first visit of the flat fee group. The remaining
visits have zero payments. Thus, if the first visit in the flat fee group
occurred prior to 1997, all of the events that occurred in 1997 will have zero
payments. Conversely, if the first event in the flat fee group occurred at the
end of 1997, the total expenditure for the entire flat fee group will be on that
event, regardless of the number of events it covered after 1997.
Zero Expenditures
There are some medical events reported by respondents
where the payments were zero. This could occur for several reasons including (1)
free care was provided, (2) bad debt was incurred, (3) care was covered under a
flat fee arrangement beginning in an earlier year, or (4) follow-up visits were
provided without a separate charge (e.g. after a surgical procedure). If all of
the medical events for a person fell into one of these categories, then the
total annual expenditures for that person would be zero.
Discount Adjustment Factor
An adjustment was also applied to some HC reported
expenditure data because an evaluation of matched HC/MPC data showed that
respondents who reported that charges and payments were equal were often unaware
that insurance payments for the care had been based on a discounted charge. To
compensate for this systematic reporting error, a weighted sequential hot-deck
imputation procedure was implemented to determine an adjustment factor for HC
reported insurance payments when charges and payments were reported to be equal.
As for the other imputations, selected predictor variables were used to form
groups of donor and recipient events for the imputation process.
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2.5.7.3 Emergency Room/Hospital
Inpatient Stay Expenditures
It is common for an emergency room visit to result in a
hospitalization. However, while it is true that all of the event files can be
linked by DUPERSID, there is no unique record link between hospital inpatient
stays and emergency room visits. However, where ever this relationship could be
identified (using MPC start and end date of the events as well as information
from the provider), the expenditure associated with the emergency room visit was
moved to the hospital facility expenditure (see ERHEVIDX in Section 2.5.1.2 ).
Hence, the expenditures (and charges) for some emergency room visits are
included in the resulting hospitalization. In these situations, the emergency
room record on this file will have its expenditure (and charge) information
zeroed out to avoid double-counting while its corresponding hospital inpatient
stay record on MEPS 1997 Hospital Inpatient Stays File will have the combined
expenditures. Please note that any physician expenditures associated with
emergency room event may remain on the emergency room event file. The variable
ERHEVIDX identifies these emergency room visits whose expenditures are included
in the expenditures for the following hospital inpatient stay. It should also be
noted that, for these cases, there is only one hospital stay associated with the
emergency room stay.
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2.5.7.4 Sources of Payment
In addition to total expenditures, variables are provided
which itemize expenditures according to major sources of payment categories.
These categories are:
1. Out-of-pocket by user or family
2. Medicare
3. Medicaid
4. Private Insurance
5. Veteran's Administration, excluding CHAMPVA
6. CHAMPUS or CHAMPVA
7. Other Federal sources - includes Indian Health Service,
Military Treatment Facilities, and other care by the Federal government
8. Other State and Local Source - includes community and
neighborhood clinics, State and local health departments, and State programs
other than Medicaid.
9. Worker's Compensation
10. Other Unclassified Sources - includes sources such as
automobile, homeowner's, liability, and other miscellaneous or unknown sources.
Two additional sources of payment variables were created
to classify payments for events with apparent inconsistencies between health
insurance coverage and sources of payment based on data collected in the survey.
These variables include:
11. Other Private - any type of private insurance payments
reported for persons not reported to have any private health insurance coverage
during the year as defined in MEPS; and
12. Other Public - Medicaid payments reported for persons
who were not reported to be enrolled in the Medicaid program at any time during
the year.
Though relatively small in magnitude, users should
exercise caution when interpreting the expenditures associated with these two
additional sources of payment. While these payments stem from apparent
inconsistent responses to health insurance and sources of payment questions in
the survey, some of these inconsistencies may have logical explanations. For
example, private insurance coverage in MEPS is defined as having a major medical
plan covering hospital and physician services. If a MEPS sampled person did not
have such coverage but had a single service type insurance plan (e.g. dental
insurance) that paid for a particular episode of care, those payments may be
classified as "other private." Some of the "other public"
payments may stem from confusion between Medicaid and other state and local
programs or may be from persons who were not enrolled in Medicaid, but were
presumed eligible by a provider who ultimately received payments from the
program.
Users should also note that the Other Public and Other
Private sources of payment categories only exist on File 1 for imputed
expenditure data since they were created through the editing/imputation process.
File 2 reflect 10 sources of payment as they were collected through the survey
instrument.
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2.5.7.5 Imputed Emergency Room Expenditure Variables
This file contains 2 sets of imputed expenditure
variables: facility expenditures and physician expenditures.
Emergency Room Facility Expenditures
(ERFSF97X-ERFOT97X, ERFXP97X, ERFTC97X)
Emergency room expenses include all expenses for
treatment, services, tests, diagnostic and laboratory work, x-rays, and similar
charges, as well as any physician services included in the emergency room
charge.
Emergency room facility expenditures were obtained
primarily through the MPC. If the physician charges were included in the
emergency room visit bill, then this expenditure is included in the facility
expenditure variables. The imputed facility expenditures provided on this file,
ERFSF97X - ERFOT97X are also the 12 sources of payment: self/family, Medicare,
Medicaid, private insurance, Veterans Administration, CHAMPUS/CHAMPVA, other
federal, state/local governments, Workman's Compensation, other private
insurance, other public insurance and other insurance. ERFXP97X is the sum of
the 12 sources of payments for the facility expenditure and ERFTC97X is the
total charge. Please note that where an emergency room visit record is linked to
a hospital inpatient stay record, ERFTC97X has been zeroed out.
Emergency Room Physician Expenditures (ERDSF97X -
ERDOT97X, ERDXP97X ERDTC97X)
Separately billing doctor (SBD) expenses typically cover
services provided to patients in hospital settings by providers like
anesthesiologists, radiologists, and pathologists, whose charges are often not
included in emergency room visit bills.
For physicians who bill separately (i.e. outside the
emergency room visit bill), a separate data collection effort within the Medical
Provider Component was performed to obtain this same set of expenditure
information from each separately billing doctor. It should be noted that there
could be several separately billing doctors associated with a medical event. For
example, an emergency room visit could have a radiologist, and an internist
associated with it. If their services are not included in the emergency room
visit bill then this is one medical event with 2 separately billing doctors. The
imputed expenditure information associated with the separately billing doctors
was summed to the event level and is provided on the file. ERDSF97X - ERDOT97X
are the 12 sources of payment, ERDXP97X is the sum of the 12 sources of
payments, and ERDTC97X is the total charge.
Analysts need to take into consideration whether to
analyze facility and SBD expenditures separately, combine them within service
categories, or collapse them across service categories (e.g. combine SBD
expenditures with expenditures for physician visits to offices and/or outpatient
departments).
Total Expenditures and Charges for Emergency Room
Visits (EREXP97X, ERTC97X)
Analysts interested in total expenditure should use the
variable EREXP97X, which includes both the facility and physician amounts. Those
interested in total charges (see 2.5.7.1 for an explanation of the
"charge" concept) should use the variable ERTC97X. However, please
note that where the emergency room visit is linked to a hospital inpatient stay
record, ERFTC97 has been zeroed out, and thus, ERTC97X may be equal to '0' or
the doctor total charge (ERDTC97X).
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2.5.7.6 Rounding
Expenditure variables on File 1, have been rounded to the
nearest penny. Person-level expenditure information released on the MEPS 1997
Person Level Use and Expenditure File were rounded to the nearest dollar. It
should be noted that using the MEPS 1997 event files HC-016A through HC-016H to
create person-level totals will yield slightly different totals than those found
on HC-020 the 1997 Person Level Use and Expenditure File. These differences are
due to rounding only. Moreover, in some instances, the number of persons having
expenditures on the MEPS 1997 event files for a particular source of payment may
differ from the number of persons with expenditures on the 1997 Person Level Use
and Expenditures File for that source of payment. This difference is also
artifact of rounding only. Please see the Appendix File for details on such
rounding differences.
2.5.7.7 Imputation Flags (IMPERFSF - IMPERCHG)
The variables IMPERFSF - IMPERCHG identify records where
sources of payment and total charge for the facility portion of the expenditure
have been imputed using the methodologies outlined in this document.
Number of Physician Records (IMPERNUM)
The variable IMPERNUM indicates the number of physician
records associated with the emergency room visit where the physician portion of
the expenditures have been imputed. The number of physicians associated with
individual sources of payment is not available.
When a record was identified as being the leaf of a flat
fee group, the values of all imputation flags were set to 0 UNIMPUTED since they
were not included in the imputation process.
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2.6 File 2 Contents: Pre-imputed Expenditure Variables
Both pre-imputed and unimputed expenditure data are
provided on this file. This means that only a series of logical edits were
applied to both the HC and MPC data to correct for several problems including
outliers, co-payments or charges reported as total payments, and reimbursed
amounts counted as out-of-pocket payments. Edits were also implemented to
correct for mis-classifications between Medicare and Medicaid and between
Medicare HMO's and private HMO's as payment sources as well as a number of other
data inconsistencies that could be resolved through logical edits. Missing data
were not imputed.
As described previously, there are several components that
went into creating the total medical expenditure variable: household reported
expenditure data and provider reported expenditure data. Both sets of
expenditure data are provided in their pre-imputed form and have not gone
through the same level of quality control as their imputed counterpart. This
means that (in some instances) there are large amounts of missing data. The
household and provider reported facility pre-imputed expenditure data are provided on this file (ERSF97H - EROT97H and
ERFSF97M-ERFOT97M respectively). For the variables ERFSF97M-ERFTC97M the user
needs to be aware that there are 3,562 records with a value of -1, NOT
APPLICABLE. For analytical purposes these records should be collapsed with those
records having a value of -9, NOT ASCERTAINED.
The user shall note that there exist only 10 sources of
payment variables in the pre-imputed expenditure data on File 2, while the
imputed expenditure data on File 1 contains 12 sources of payment variables. The
additional two sources of payment (which are not reported as separate sources of
payment through the data collection) are Other Private and Other Public. These
sources of payment categories were constructed to resolve apparent
inconsistencies between individuals' reported insurance coverage and their
sources of payment for specific events.
The user should also note that the variable HHSFFIDX,
which is the original flat fee identifier that was derived during the household
interview, should only be used if the user interested in performing their own
expenditure imputation.
Finally, the user should note that the variable ERUC97H
regarding uncollected liability is collected and stored only on File 2.
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3.0 Sample Weights and
Variance Estimation Variables (WTDPER97-VARPSU97)
3.1 Overview
There is a single full year person-level weight (WTDPER97)
included on the MEPS 1997 Emergency Room Visits File file. A person-level weight
was assigned to each emergency room visit reported by a key, in-scope person who
responded to MEPS for the full period of time that he or she was in-scope during
1997. A key person either was a member of an NHIS household at the time of the
NHIS interview, or became a member of such a household after being out-of-scope
at the time of the NHIS (examples of the latter situation include newborns and
persons returning from military service, an institution, or living outside the
United States). A person is in-scope whenever he or she is a member of the
civilian noninstitutionalized portion of the U.S. population.
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3.2 Details on Person Weights Construction
The person-level weight WTDPER97 was developed in three
stages. A person level weight for Panel 2 was created, including both an
adjustment for nonresponse over time and poststratification, controlling to
Current Population Survey (CPS) population estimates based on five variables.
Variables used in the establishment of person-level poststratification control
figures included: census region (Northeast, Midwest, South, West); MSA status (MSA,
non-MSA); race/ethnicity (Hispanic, black but non-Hispanic, and other); sex; and
age. Then a person level weight for Panel 1 was created, again including an
adjustment for nonresponse over time and poststratification, again controlling
to CPS population estimates based on the same five variables. When poverty
status information derived from income variables became available, a 1997
composite weight was formed from the Panel 1 and Panel 2 weights by multiplying
the panel weights by .5. Then a final poststratification was done on this
composite weight variable, including poverty status (below poverty, from 100 to
125 percent of poverty, from 125 to 200 percent of poverty, from 200 to 400
percent of poverty, at least 400 percent of poverty) as well as the original
five poststratification variables in the establishment of control totals.
The panel specific weights described below in Sections
3.2.1 and 3.2.2 are not available on the current file. This additional
information is provided for reference only. In order to determine in which panel
a sampled person participated, users must link to the 1997 Full Year Population
Characteristics File to obtain the variable PANEL97.
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3.2.1 MEPS Panel 1 Weight
The person level weight for MEPS Panel 1 was developed
using the 1996 full year weight for an individual as a "base" weight
for survey participants present in 1996. For key, in-scope respondents who
joined an RU some time in 1997 after being out-of-scope in 1996, the 1996 family
weight associated with the family the person joined served as a "base"
weight. The weighting process included an adjustment for nonresponse over Rounds
4 and 5 as well as poststratification to population control figures for
December, 1997. These control figures were derived by scaling back the
population totals obtained from the March 1998 CPS to reflect the December, 1997
CPS estimated population distribution across age and sex categories as of
December, 1997. Variables used in the establishment of person level
poststratification control figures included: census region (Northeast, Midwest,
South, West); MSA status (MSA, non-MSA); race/ethnicity (Hispanic, black but
non-Hispanic, and other); sex, and age. Overall, the weighted population
estimate for the civilian, noninstitutionalized population on December 31, 1997
is 267,704,802. Key, responding persons not in-scope on December 31, 1997 but
in-scope earlier in the year retained, as their final Panel 1 weight, the weight
after the nonresponse adjustment.
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3.2.2 MEPS Panel 2 Weight
The person level weight for MEPS Panel 2 was developed
using the MEPS Round 1 person-level weight as a "base" weight. For
key, in-scope respondents who joined an RU after Round 1, the Round 1 family
weight served as a "base" weight. The weighting process included an
adjustment for nonresponse over Round 2 and the 1997 portion of Round 3 as well
as poststratification to the same population control figures for December 1997
used for the MEPS Panel 1 weights. The same five variables employed for Panel 1
poststratification (census region, MSA status, race/ethnicity, sex, and age)
were used for Panel 2 poststratification. Similarly, for Panel 2, key,
responding persons not in-scope on December 31, 1997 but in-scope earlier in the
year retained, as their final Panel 2 weight, the weight after the nonresponse
adjustment.
Note that the MEPS Round 1 weights (for both panels with
one exception as noted below) incorporated the following components: the
original household probability of selection for the NHIS; ratio-adjustment to
NHIS-based national population estimates at the household (occupied dwelling
unit) level; the probability of selection of dwelling units associated with the
oversampling of five population domains of analytic interest (for Panel 2 only);
adjustment for nonresponse at the dwelling unit level for Round 1; and
poststratification to figures at the family and person level obtained from the
March 1997 CPS data base. The five oversampled domains for Panel 2 were
households with: persons with functional impairments; children with limitations
in activity; individuals 18-64 expected to incur high medical expenditures based
on a statistical model; persons with family incomes expected to be below 200
percent of poverty based on a statistical model; and adults with other
impairments.
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3.2.3 The Final Weight for 1997
Variables used in the establishment of person level
poststratification control figures included: poverty status (below poverty, from
100 to 125 percent of poverty, from 125 to 200 percent of poverty, from 200 to
400 percent of poverty, at least 400 percent of poverty); census region
(Northeast, Midwest, South, West); MSA status (MSA, non-MSA); race/ethnicity
(Hispanic, black but non-Hispanic, and other); sex, and age. Overall, the
weighted population estimate for the civilian, noninstitutionalized population
for December 31, 1997 is 267,704,802 (WTDPER97>0 and INSC1231=1). The
inclusion of key, in-scope persons who were not in-scope on December 31, 1997
brings the estimated total number of persons represented by the MEPS respondents
over the course of the year up to 271,278,585 (WTDPER97>0). The weighting
process included poststratification to population totals obtained from the 1996
MEPS Nursing Home Component for the number of individuals admitted to nursing
homes. For the 1996 full year file an additional poststratification was done to
population totals obtained from the 1996 Medicare Current Beneficiary Survey (MCBS)
for the number of deaths among Medicare beneficiaries experienced in the 1996
MEPS. However, in 1997 the difference between the MEPS and MCBS estimates was
not statistically significant, and no adjustment was made.
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3.2.4 Coverage
The target population for MEPS in this file is the 1997
U.S. civilian, noninstitutionalized population. However, the MEPS sampled
households are a subsample of the NHIS households interviewed in 1995 (Panel 1)
and 1996 (Panel 2). New households created after the NHIS interviews for the
respective Panels and consisting exclusively of persons who entered the target
population after 1995 (Panel 1) or after 1996 (Panel 2) are not covered by MEPS.
These would include families consisting solely of: immigrants; persons leaving
the military; U.S. citizens returning from residence in another country; and
persons leaving institutions. It should be noted that this set of uncovered
persons constitutes only a tiny proportion of the MEPS target population
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4.0 Strategies for
Estimation
This file is constructed for efficient estimation of
utilization, expenditure, and sources of payment for hospital emergency room
visits and to allow for estimates of number of persons with emergency room
visits for 1997.
4.1 Variables with Missing
Values
It is essential that the analyst examine all variables for
the presence of negative values used to represent missing values. For example, a
record with a value of -8 for the first ICD9 condition code (ERICD1X) indicates
that the condition was reported as unknown.
For continuous or discrete variables, where means or
totals may be taken, it may be necessary to set minus values to values
appropriate to the analytic needs. That is, the analyst should either impute a
value or set the value to one that will be interpreted as missing by the
computing language used. For categorical and dichotomous variables, the analyst
may want to consider whether to recode or impute a value for cases with negative
values or whether to exclude or include such cases in the numerator and/or
denominator when calculating proportions.
Methodologies used for the editing/imputation of
expenditure variables (e.g. sources of payment flat fee, hospital/er, and zero
expenditures) are described in Section 2.5.7.2.
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4.2 Basic Estimates of
Utilization, Expenditure and Sources of Payment
While the examples described below illustrate the use of
event level data in constructing person-level total expenditures, these
estimates can also be derived from the person-level expenditure file unless the
characteristic of interest is event specific.
In order to produce national estimates related to
emergency room utilization, expenditures and sources of payment, the value in
each record contributing to the estimates must be multiplied by the weight
(WTDPER97) contained on that record.
Example 1:
For example, the total number of emergency room visits,
for the civilian non-institutionalized population of the U.S. in 1997, is
estimated as the sum of the weight (WTDPER97) across all emergency room visit
records. That is,
Sum of Wj=44,920,484 (1)
Various estimates can be produced based on specific
variables and subsets of records.
Example 2:
For example, the estimate for the mean out-of-pocket
payment per emergency room visit should be calculated as the weighted mean of
the facility bill and doctor's bill paid by self/family. That is,
X bar =(Sum of WjXj) / (Sum of Wj)= $75.02, (2)
where Xj = ERFSF97Xj + ERDSF97Xj and Sum of Wj=41,560,406
for all emergency room visits with EREXP97Xj > 0.
This gives $75.02 as the estimated mean amount of
out-of-pocket payment of expenditures associated with emergency room visits and
41,560,406 as an estimate of the total number of emergency room visits with
expenditures. Both of these estimates are for the civilian non-institutionalized
population of the U.S. in 1997.
Example 3:
Another example would be to estimate the average
proportion of total expenditures paid by private insurance for emergency room
visits with expenditures. This should be calculated as the weighted mean of the
proportion of total expenditures paid by private insurance at the event level.
That is
Y bar =(Sum of WjYj) / (Sum of Wj)=0.4353, (3)
where Yj=(ERFPV96Xj + ERDPV96Xj) / EREXP96Xj and Sum of Wj=41,560,406
for all emergency room visits with EREXP97Xj > 0.
This gives 0.4353 as the estimated mean proportion of
total expenditures paid by private insurance for emergency room visits with
expenditures for the civilian non-institutionalized population of the U.S. in
1997.
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4.3 Estimates of the Number of Persons with Emergency Room Visit
When calculating an estimate of the total number of
persons with emergency room visits, users can use a person-level file (MEPS 1997
Person Level Use and Expenditure File) or the emergency room visits file.
However, the current file must be used, when the measure of interest is defined
at the event level. For example, to estimate the number of persons with
emergency room visits where the patient sees a doctor, the current file must be
used. This would be estimated as,
Sum of WiXi across all unique persons i on this file, (4)
where
Wi is the sampling weight(WTDPER97) for
person i
and
Xi = 1 if SEEDOC EQ 1for any event of
person i
= 0 otherwise.
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4.4 Person-Based Ratio
Estimates
4.4.1 Person-Based Ratio Estimates Relative to Persons with Emergency Room Use
This file may be used to derive person-based ratio
estimates. However, when calculating ratio estimates where the denominator is
persons, care should be taken to properly define the unit of analysis as
person-level. For example, the mean expense for persons with emergency room
visit is estimated as,
(Sum of WiZi) / (Sum of Wi) across all unique persons i on this file, (5)
where
Wi is the sampling weight (WTDPER97) for
person i
and
Zi = Sum of ERXP96Xj across all visits for person i.
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4.4.2 Person-Based Ratio Estimates
Relative to the Entire Population
If the ratio relates to the entire population, this file
cannot be used to calculate the denominator, as only those persons with at least
one emergency room visit are represented on this data file. In this case 1997
MEPS Person Level Use and Expenditure File, which has data for all sampled
persons, must be used to estimate the total number of persons (i.e. those with
use and those without use). For example, to estimate the proportion of civilian
non-institutionalized population of the U.S. with at least one emergency room
visit where s/he saw a doctor, the numerator would be derived from data on the
current file, and the denominator should be derived from data on the 1997 MEPS
Person Level Use and Expenditure File. That is,
(Sum of WiZi) / (Sum of Wi) across all unique persons i on the person level file, (6)
where
Wi is the sampling weight(WTDPER97) for
person i
and
Zi = 1 if SEEDOCj EQ 1 for
any visit of person i on the emergency room visit file
= 0 otherwise for all remaining persons on the
MEPS HC-020: Person Level Use and Expenditure File.
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4.5 Sampling Weights for
Merging Previous Releases of MEPS Household Data with the Emergency Room Visits
File
There have been several previous releases of MEPS
Household Survey public use data. Unless a variable name common to several tapes
is provided, the sampling weights contained on these data files are
file-specific. The file-specific weights reflect minor adjustments to
eligibility and response indicators due to birth, death, or institutionalization
among respondents.
In general, for estimates from a MEPS data file that do
not require merging with variables from other MEPS data files, the sampling
weight(s) provided on that data file are the appropriate weight(s). When merging
a MEPS Household data file to another, the major analytical variable (i.e. the
dependent variable) determines the correct sampling weight to use.
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4.6 Variance Estimation
To obtain estimates of variability (such as the standard
error of sample estimates or corresponding confidence intervals) for estimates
based on MEPS survey data, one needs to take into account the complex sample
design of MEPS. Various approaches can be used to develop such estimates of
variance including use of the Taylor series or various replication
methodologies. Replicate weights have not been developed for the MEPS 1997 data.
Variables needed to implement a Taylor series estimation approach are described
in the paragraph below.
Using a Taylor Series approach, variance estimation strata
and the variance estimation PSUs within these strata must be specified. The
corresponding variables on the MEPS full year utilization database are VARSTR97
and VARPSU97, respectively. Specifying a "with replacement" design in
a computer software package such as SUDAAN (Shah, 1996) should provide standard
errors appropriate for assessing the variability of MEPS survey estimates. It
should be noted that the number of degrees of freedom associated with estimates
of variability indicated by such a package may not appropriately reflect the
actual number available. For MEPS sample estimates for characteristics generally
distributed throughout the country (and thus the sample PSUs), there are over
100 degrees of freedom associated with the corresponding estimates of variance.
The following illustrates these concepts using two examples from Section 4.2.
Example 2 from Section 4.2
Using a Taylor Series approach, specifying VARSTR97 and
VARPSU97 as the variance estimation strata and PSUs (within these strata)
respectively and specifying a "with replacement" design in the
computer software package SUDAAN will yield an estimate of standard error of
$6.01 for the estimated mean of out-of-pocket payment.
Example 3 from Section 4.2
Using a Taylor Series approach, specifying VARSTR97 and
VARPSU97 as the variance estimation strata and PSUs (within these strata)
respectively and specifying a "with replacement" design in the
computer software package SUDAAN will yield an estimate of standard error of
0.0113 for the weighted mean proportion of total expenditures paid by private
insurance.
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5.0 Merging/Linking MEPS Data
Files
Data from the 1997 Emergency Room Visits File can be used
alone or in conjunction with other files. This section provides instructions for
linking the emergency room visits files with other MEPS public use files,
namely, the person-level file, the prescribed medicines file, and the conditions
file.
5.1 Merging a Person-Level File to the Emergency Room Visit File
Merging characteristics of interest from person-level
files (e.g., MEPS1997 Full Year Population Characteristics File, or MEPS1997
Person Level Use and Expenditure File) expands the scope of potential estimates.
To estimate the total number of emergency room visits for persons with specific
demographic characteristics (e.g., age, race, and sex), population
characteristics from a person-level file need to be merged onto the emergency
room visit file. This procedure is illustrated below. The Appendix File provides
additional detail on how to merge MEPS data files.
1. Create data set PERS by sorting the MEPS 1997 Full
Year Population Characteristics File, by the person identifier, DUPERSID. Keep
only variables to be merged on to the emergency room visit file and DUPERSID.
2. Create data set EROM by sorting the emergency room
visit file by person identifier, DUPERSID.
3. Create final data set NEWEROM by merging these two
files by DUPERSID, keeping only records on the emergency room visit file.
The following is an example of SAS code which completes
these steps:
PROC SORT DATA=HCXXX(KEEP=DUPERSID AGE SEX RACEX)
OUT=PERSX;
BY DUPERSID;
RUN;
PROC SORT DATA=EROM;
BY DUPERSID;
RUN;
DATA NEWEROM;
MERGE EROM (IN=A) PERSX(IN=B);
BY DUPERSID;
IF A;
RUN;
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5.2 Linking the 1997 Emergency
Room Visits File to the 1997 Medical Conditions File and/or the 1997 Prescribed
Medicines File
Because of survey design issues, there are
limitations/caveats that an analyst must keep in mind when linking the different
files. Those limitations/caveats are listed below. For detailed linking
examples, including SAS code, analysts should refer to the Appendix File.
5.3 Limitations/Caveats of
RXLK (the Prescribed Medicine Link File)
The RXLK file provides a link from the MEPS event files to
records on the 1997 Prescribed Medicine File. When using RXLK, analysts should
keep in mind that one emergency room visit can link to more than one prescribed
medicine record. Conversely, a prescribed medicine event may link to more than
one emergency room visit or different types of events. When this occurs, it is
up to the analyst to determine how the prescribed medicine expenditures should
be allocated among those medical events.
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5.4 Limitations/Caveats of CLNK (the Medical Conditions Link File)
The CLNK provides a link from MEPS event files to the 1997
Medical Conditions File. When using the CLNK, analysts should keep in mind that
(1) conditions are self-reported and (2) there may be multiple conditions
associated with an emergency room visit. Users should also note that not all
emergency room visits link to the medical conditions file.
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References
Cohen, S.B. (1998). Sample Design of the 1996 Medical
Expenditure Panel Survey Medical Provider Component. Journal of Economic Social Measurement.
Vol 24, 25-53.
Cohen, S.B. (1997). Sample Design of the 1996 Medical
Expenditure Panel Survey Household Component. Rockville (MD): Agency for Health
Care Policy and Research; 1997. MEPS
Methodology Report, No. 2. AHCPR Pub. No. 97-0027.
Cohen, J.W. (1997). Design and Methods of the Medical
Expenditure Panel Survey Household Component. Rockville (MD): Agency for Health
Care Policy and Research; 1997. MEPS
Methodology Report, No. 1. AHCPR Pub. No. 97-0026.
Cohen, S.B. (1996). The Redesign of the Medical
Expenditure Panel Survey: A Component of the DHHS Survey Integration Plan. Proceedings of the COPAFS Seminar on Statistical Methodology
in the Public Service.
Cox, B.G. and Cohen, S.B. (1985). Chapter 6: A Comparison
of Household and Provider Reports of Medical Conditions. In Methodological Issues for Health Care Surveys. Marcel Dekker, New York.
Cox, B.G. and Cohen, S.B. (1985). Chapter 8: Imputation
Procedures to Compensate for Missing Responses to Data Items. In Methodological Issues for Health Care Surveys. Marcel Dekker, New York.
Cox, B. and Iachan, R. (1987). A Comparison of Household
and Provider Reports of Medical Conditions. Journal of Economic and Social Measurement.
82(400):1013-18.
Edwards, W.S., Winn, D.M., Kurlantzick V., et al. (1994).
Evaluation of National Health Interview Survey Diagnostic Reporting. National
Center for Health Statistics, Vital Health 2(120).
Elixhauser A., Steiner C.A., Whittington C.A., and
McCarthy E. Clinical Classifications for Health Policy Research: Hospital
Inpatient Statistics, 1995. Healthcare Cost and Utilization Project, HCUP-3
Research Note. Rockville, MD: Agency for Health Care Policy and Research; 1998.
AHCPR Pub. No. 98-0049.
Health Care Financing Administration (1980). International
Classification of Diseases, 9th Revision, Clinical Modification (ICD-CM).
Vol. 1. (DHHS Pub. No. (PHS) 80-1260). DHHS: U.S. Public Health Services.
Johnson, A.E. and Sanchez, M.E. (1993). Household and
Medical Provider Reports on Medical Conditions: National Medical Expenditure
Survey, 1987. Journal of Economic and Social
Measurement. Vol. 19, 199-233.
Monheit, A.C., Wilson, R., and Arnett, III, R.H.
(Editors). Informing American Health Care Policy. (1999). Jossey-Bass Inc, San
Francisco.
Shah, B.V., Barnwell, B.G., Bieler, G.S., Boyle, K.E.,
Folsom, R.E., Lavange, L., Wheeless, S.C., and Williams, R. (1996). Technical Manual: Statistical Methods and Algorithms Used in SUDAAN
Release 7.0, Research Triangle Park, NC: Research Triangle Institute.
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Attachment 1
Definitions
Dwelling Units, Reporting Units, Families, and Persons The definitions of Dwelling Units (Dus) and Group Quarters in the MEPS
Household Survey are generally consistent with the definitions employed for the
National Health Interview Survey.
The dwelling unit ID (DUID) is a five-digit random ID
number assigned after the case was sampled for MEPS. The person number (PID)
uniquely identifies all persons within the dwelling unit. The variable DUPERSID
is the combination of the variables DUID and PID.
A Reporting Unit (RU) is a person or group of persons in
the sampled dwelling unit who are related by blood, marriage, adoption or other
family association, and who are to be interviewed as a group in MEPS. Thus, the
RU serves chiefly as a family-based "survey operations" unit rather
than an analytic unit. Regardless of the legal status of their association, two
persons living together as a "family" unit were treated as a single
reporting unit if they chose to be so identified.
Unmarried college students under 24 years of age who
usually live in the sampled household, but were living away from home and going
to school at the time of the Round 1 MEPS interview, were treated as a Reporting
Unit separate from that of their parents for the purpose of data collection.
These variables can be found on MEPS person level files.
In-Scope A person was classified as
in-scope (IN-SCOPE) if he or she was a member of the U.S. civilian,
non-institutionalized population at some time during the Round 1 interview. This
variable can be found on MEPS person level files.
Keyness The term "keyness" is
related to an individual's chance of being included in MEPS. A person is key if
that person is appropriately linked to the set of NHIS sampled households
designated for inclusion in MEPS. Specifically, a key person either was a member
of an NHIS household at the time of the NHIS interview, or became a member of
such a household after being out-of-scope prior to joining that household
(examples of the latter situation include newborns and persons returning from
military service, an institution, or living outside the United States).
A non-key person is one whose chance of selection for the
NHIS (and MEPS) was associated with a household eligible but not sampled for the
NHIS, who happened to have become a member of a MEPS reporting unit by the time
of the MEPS Round 1 interview. MEPS data, (e.g., utilization and income) were
collected for the period of time a non-key person was part of the sampled unit
to permit family level analyses. However, non-key persons who leave a sample
household would not be recontacted for subsequent interviews. Non-key
individuals are not part of the target sample used to obtain person level
national estimates.
It should be pointed out that a person may be key even
though not part of the civilian, non-institutionalized portion of the U.S.
population. For example, a person in the military may be living with his or her
civilian spouse and children in a household sampled for the NHIS. The person in
the military would be considered a key person for MEPS. However, such a person
would not receive a person-level sample weight so long as he or she was in the
military. All key persons who participated in the first round of a MEPS panel
received a person level sample weight except those who were in the military. The
variable indicating "keyness" is KEYNESS. This variable can be found
on MEPS person level files.
Eligibility The eligibility of a
person for MEPS pertains to whether or not data were to be collected for that
person. All key, in-scope persons of a sampled RU were eligible for data
collection. The only non-key persons eligible for data collection were those who
happened to be living in the same RU as one or more key persons, and their
eligibility continued only for the time that they were living with a key person.
The only out-of-scope persons eligible for data collection were those who were
living with key in-scope persons, again only for the time they were living with
a key person. Only military persons meet this description. A person was
considered eligible if they were eligible at any time during Round 1. The
variable indicating "eligibility" is ELIGRND1, where 1 is coded for
persons eligible for data collection for at least a portion of the Round 1
reference period, and 2 is coded for persons not eligible for data collection at
any time during the first round reference period. This variable can be found on
MEPS person level files.
Pre-imputed - When only a series of
logical edits were applied to the HC data to correct for several
problems--including outliers, copayments or charges reported as total payments,
and reimbursed amounts counted as out of pocket payments--these variables are
labeled "pre-imputed." Missing data remain.
Unimputed - When only a series of
logical edits were applied to the MPC data to correct for several problems
--including outliers, copayments or charges reported as total payments, and
reimbursed amounts counted as out of pocket payments--these variables were
labeled "unimputed" and were used as the imputation source to account
for missing HC data.
Imputation -Imputation is a technique
more often used for items missing data adjustment through the use of predictive
models for the missing data; it is based on data available on the same (or
similar) cases. Hot-deck imputation creates a data set with complete data for
all nonrespondent cases, often by substituting the data from a respondent case
that resembles the nonrespondent on certain known variables.
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D. Codebooks
(link to separate file)
E.
Variable-Source Crosswalk
FOR MEPS HC-010E: 1997 EMERGENCY ROOM VISITS
File 1:
Survey Administration and ID Variables
Variable |
Description |
Source |
DUID |
Dwelling unit ID |
Assigned in sampling |
PID |
Person number |
Assigned in sampling |
DUPERSID |
Sample person ID |
Assigned in sampling |
EVNTIDX |
Event ID |
Assigned in Sampling |
EVENTRN |
Event round number |
CAPI derived |
ERHEVIDX |
Flag indicate hospital stay associated with the ER
visit |
Constructed |
FFEEIDX |
Flat fee ID |
CAPI derived |
MPCDATA |
MPC data flag |
CAPI derived |
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Characteristics of Emergency Room Visits Variables
Variable |
Description |
Source |
ERDATEYR |
Event date year |
CAPI derived |
ERDATEMM |
Event date month |
CAPI derived |
ERDATEDD |
Event date day |
CAPI derived |
SEEDOC |
Did P see medical doctor during this visit |
ER01 |
VSTCTGRY |
Best category for EROM care on visit |
ER02 |
VSTRELCN |
Was this visit related to special health condition |
ER03 |
LABTEST |
During the visit did the P have lab tests |
ER05 |
SONOGRAM |
During this visit did P have sonog/ultras |
ER05 |
XRAYS |
During this visit did P have xrays |
ER05 |
MAMMOG |
During this visit did P have mammogram |
ER05 |
MRI |
During this visit did P have MRI/CATSCAN |
ER05 |
EKG |
During this visit did P have EKG or ECG |
ER05 |
EEG |
During this visit did P have EEG |
ER05 |
RCVVAC |
During this visit did P receive vaccination |
ER05 |
ANESTH |
During this visit did P receive anesthesia |
ER05 |
OTHSVCE |
During this visit did P have OTH TSTS/EXM |
ER05 |
SURGPROC |
Surgical procedure performed on P during visit |
ER06 |
SURGNAME |
Surgical procedure name in categories |
ER07 |
MEDPRESC |
This visit were any medicines prescribed for P |
ER08 |
DOCOUTF |
Did person see any ER docs outside of ER |
ER10 |
VAPLACE |
Emergency room is a VA facility |
Constructed |
ERICD1X |
3-digit ICD-9 condition code |
Edited |
ERICD2X |
3-digit ICD-9 condition code |
Edited |
ERICD3X |
3-digit ICD-9 condition code |
Edited |
ERPRO1X |
2-digit ICD-9 procedure code |
Edited |
ERCCC1X |
Modified Clinical Classification Code |
Constructed/Edited |
ERCCC2X |
Modified Clinical Classification Code |
Constructed/Edited |
ERCCC3X |
Modified Clinical Classification Code |
Constructed/Edited |
NUMCOND |
Total number of COND records linked to this event |
Constructed |
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Flat Fee Variables
Variable |
Description |
Source |
FFERTYPE |
Flat fee bundle |
FF01, FF02 |
Imputed Total Expenditure Variables
Variable |
Description |
Source |
EREXP97X |
Total expenditure for emergency room visit |
Constructed |
ERTC97X |
Total charge for emergency room visit |
Constructed |
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Imputed Facility Expenditure Variables
Variable |
Description |
Source |
ERFSF97X |
Facility amount paid, family (imputed) |
CP11 (Edited/Imputed) |
ERFMR97X |
Facility amount paid, Medicare (imputed) |
CP09 (Edited/Imputed) |
ERFMD97X |
Facility amount paid, Medicaid (imputed) |
CP07 (Edited/Imputed) |
ERFPV97X |
Facility amount paid, private insurance (imputed) |
CP07 (Edited/Imputed) |
ERFVA97X |
Facility amount paid, Veterans (imputed) |
CP07 (Edited/Imputed) |
ERFCH97X |
Facility amount paid, CHAMP/CHAMPVA (imputed) |
CP07 (Edited/Imputed) |
ERFOF97X |
Facility amount paid, other federal (imputed) |
CP07 (Edited/Imputed) |
ERFSL97X |
Facility amount paid, state/local govt. (imputed) |
CP07 (Edited/Imputed) |
ERFWC97X |
Facility amount paid, Workers Comp (imputed) |
CP07 (Edited/Imputed) |
ERFOR97X |
Facility amount paid, other private (imputed) |
Constructed |
ERFOU97X |
Facility amount paid, other public (imputed) |
Constructed |
ERFOT97X |
Facility amount paid, other insurance (imputed) |
CP07 (Edited/Imputed) |
ERFXP97X |
Facility sum of payments ERFSF97X ERFOT97X |
Constructed |
ERFTC97X |
Facility total charge (imputed) |
CP09 (Edited/Imputed) |
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Imputation Flag Variables
Variable |
Description |
Source |
IMPERFSF |
Imputation flag for ERFSF97X |
Constructed |
IMPERFMR |
Imputation flag for ERFMR97X |
Constructed |
IMPERFMD |
Imputation flag for ERFMD97X |
Constructed |
IMPERFPV |
Imputation flag for ERFPV97X |
Constructed |
IMPERFVA |
Imputation flag for ERFVA97X |
Constructed |
IMPERFCH |
Imputation flag for ERFCH97X |
Constructed |
IMPERFOF |
Imputation flag for ERFOF97X |
Constructed |
IMPERFSL |
Imputation flag for ERFSL97X |
Constructed |
IMPERFWC |
Imputation flag for ERFWC97X |
Constructed |
IMPERFOR |
Imputation flag for ERFOR97X |
Constructed |
IMPERFOU |
Imputation flag for ERFOU97X |
Constructed |
IMPERFOT |
Imputation flag for ERFOT97X |
Constructed |
IMPERFXP |
Imputation flag for ERFXP97X |
Constructed |
IMPERCHG |
Imputation flag for ERFTC97X |
Constructed |
IMPERNUM |
Number of Dr. records imputed per provider |
Constructed |
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Imputed Physician Expenditure Variables
Variable |
Description |
Source |
ERDSF97X |
Doctor amount paid, family (imputed) |
CP11 (Edited/Imputed) |
ERDMR97X |
Doctor amount paid, Medicare (imputed) |
CP09 (Edited/Imputed) |
ERDMD97X |
Doctor amount paid, Medicaid (imputed) |
CP07 (Edited/Imputed) |
ERDPV97X |
Doctor amount paid, private insurance (imputed) |
CP07 (Edited/Imputed) |
ERDVA97X |
Doctor amount paid, Veterans (imputed) |
CP07 (Edited/Imputed) |
ERDCH97X |
Doctor amount paid, CHAMP/CHAMPVA (imputed) |
CP07 (Edited/Imputed) |
ERDOF97X |
Doctor amount paid, other federal (imputed) |
CP07 (Edited/Imputed) |
ERDSL97X |
Doctor amount paid, state/local govt. (imputed) |
CP07 (Edited/Imputed) |
ERDWC97X |
Doctor amount paid, Workers Comp (imputed) |
CP07 (Edited/Imputed) |
ERDOR97X |
Doctor amount paid, other private (imputed) |
Constructed |
ERDOU97X |
Doctor amount paid, other public (imputed) |
Constructed |
ERDOT97X |
Doctor amount paid, other insurance (imputed) |
CP07 (Edited/Imputed) |
ERDXP97X |
Doctor sum of payments ERDSF97X ERDOT97X |
Constructed |
ERDTC97X |
Doctor total charge (imputed) |
CP09 (Edited/Imputed) |
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Weights
Variable |
Description |
Source |
WTDPER97 |
Person weight full-year 1997 (poverty adjusted) |
Constructed |
VARPSU97 |
Variance estimation PSU 1997 |
Constructed |
VARSTR97 |
Variance estimation stratum |
Constructed |
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File 2:
Survey Administration and ID Variables
Variable |
Description |
Source |
DUID |
Dwelling unit ID |
Assigned in sampling |
PID |
Person number |
Assigned in sampling |
DUPERSID |
Sample person ID |
Assigned in sampling |
EVNTIDX |
Event ID |
Assigned in Sampling |
HHSFFIDX |
Household reported flat fee ID |
CAPI derived |
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Pre-imputed Expenditure Variables
Variable |
Description |
Source |
ERSF97H |
Household reported amount paid, family (pre-imputed) |
CP11 (Edited) |
ERMR97H |
Household reported amount paid, Medicare
(pre-imputed) |
CP09 (Edited) |
ERMD97H |
Household reported amount paid, Medicaid
(pre-imputed) |
CP07 (Edited) |
ERPV97H |
Household reported amount paid, private insurance
(pre-imputed) |
CP07 (Edited) |
ERVA97H |
Household reported amount paid, Veterans
(pre-imputed) |
CP07 (Edited) |
ERCH97H |
Household reported amount paid, CHAMP/CHAMPVA
(pre-imputed) |
CP07 (Edited) |
EROF97H |
Household reported amount paid, other federal
(pre-imputed) |
CP07 (Edited) |
ERSL97H |
Household reported amount paid, state/local govt.
(pre-imputed) |
CP07 (Edited) |
ERWC97H |
Household reported amount paid, Workers Comp
(pre-imputed) |
CP07 (Edited) |
EROT97H |
Household reported amount paid, other insurance.
(pre-imputed) |
CP07 (Edited) |
ERUC97H |
Household reported amount paid, uncollected
liability (pre-imputed) |
CP07 (Edited) |
ERTC97H |
Household reported total charge (pre-imputed) |
CP09 (Edited) |
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Unimputed Expenditure Variables
Variable |
Description |
Source |
ERSF97M |
MPC reported amount paid, family (unimputed) |
HEF8a |
ERMR97M |
MPC reported amount paid, Medicare (unimputed) |
HEF8b |
ERMD97M |
MPC reported amount paid, Medicaid (unimputed) |
HEF8c |
ERPV97M |
MPC reported amount paid, private insurance (unimputed) |
HEF8d |
ERVA97M |
MPC reported amount paid, Veterans (unimputed) |
HEF8e |
ERCH97M |
MPC reported amount paid, CHAMP/CHAMPVA (unimputed) |
HEF8f |
EROF97M |
MPC reported amount paid, other federal (unimputed) |
HEF8g |
ERSL97M |
MPC reported amount paid, state/local govt. (unimputed) |
HEF8g |
ERWC97M |
MPC reported amount paid, Workers Comp (unimputed) |
HEF8g |
EROT97M |
MPC reported amount paid, other insurance (unimputed) |
HEF8g |
ERTC97M |
MPC reported total charge (unimputed) |
HEF9 |
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Weights
Variable |
Description |
Source |
WTDPER97 |
Person weight full-year 1997 (poverty adjusted) |
Constructed |
VARPSU97 |
Variance estimation PSU 1997 |
Constructed |
VARSTR97 |
Variance estimation stratum |
Constructed |
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