Scientific Data Documentation
Epidemiologic Followup Study, 1992 Mortality
ACKNOWLEDGMENTS
Overall responsibility for the data processing and the compilation and
documentation for the NHANES I Epidemiologic Followup Study (NHEFS), 1992
Mortality Data Public Use data tape rested with Christine S. Cox. Assistance
was provided by other members of the NHEFS data management team: Sandra T.
Rothwell, Michael Mussolino, Jennifer H. Madans, Dawn M. Scott, Madelyn A.
Lane, Keith Zevallos, Cordell Golden, Cynthia Reuben, Joel C. Kleinman, and
Jacob J. Feldman. Special thanks are extended to Joan Cornoni-Huntley of the
National Institute on Aging (NIA) who played an important role in the
development and continuation of the NHEFS. The contribution of the
contractor, Westat Inc., of Rockville, Maryland, who conducted the field work
is also gratefully acknowledged.
The NHEFS originated as a joint project between the National Center for Health
Statistics (NCHS) and NIA. It has been funded primarily by NIA, with
additional financial support from the following components of the National
Institutes of Health and other Public Health Service agencies: the National
Center for Chronic Disease Prevention and Health Promotion; the National
Cancer Institute; the National Heart, Lung, and Blood Institute; the National
Institute on Alcohol Abuse and Alcoholism; the National Institute of Mental
Health; the National Institute of Diabetes and Digestive and Kidney Diseases;
the National Institute of Arthritis and Musculoskeletal and Skin Diseases; the
National Institute of Allergy and Infectious Diseases; and, the National
Institute of Neurological and Communicative Disorders and Stroke.
Contents
Page
Use of NHEFS Data.................................................... 1
Errors in the Data Tapes and Survey Differences...................... 2
Introduction to the 1992 NHEFS Mortality Data Tape Documentation..... 3
NCHS Procedures Used to Code Multiple Cause Data..................... 9
1992 NHEFS Mortality Data Tape Characteristics....................... 16
1992 NHEFS Mortality Data Tape Record Layout......................... 17
1992 NHEFS Mortality Data Public Use Tape Documentation.............. 18
Appendix 1 NCHS ICD-9th Revision 282 Cause of Death Recodes.......... 37
Appendix 2 NCHS ICD-9th Revision 72 Cause of Death Recodes........... 45
Appendix 3 NCHS ICD-9th Revision 34 Cause of Death Recodes........... 47
Use of NHEFS Data
With the goal of mutual benefit, NCHS requests the cooperation of recipients
of data tapes in certain actions related to their use:
A. Any published material derived from the data should acknowledge the
National Center for Health Statistics (NCHS) as the original source.
It should also include a disclaimer which credits any analyses,
interpretations, or conclusions reached to the author (recipient of the
tape) and not to NCHS, which is responsible only for the initial data.
B. Consumers who wish to publish a technical description of the data will
make a reasonable effort to insure that the description is not
inconsistent with that published by NCHS. This does not mean, however,
that NCHS will review such descriptions.
C. Authors should provide NCHS with a reprint of published articles which
utilize the 1992 NHEFS data. Please send reprints to:
NHEFS Data Management Staff
Division of Epidemiology
National Center for Health Statistics
Presidential Building, Room 730
6525 Belcrest Road
Hyattsville, Maryland 20782
ERRORS IN THE NHEFS DATA TAPES AND SURVEY DIFFERENCES
The NHEFS Public Use data tapes have been subjected to a great deal of careful
editing. However, due to the large volume of data in the series, it is likely
that a small number of errors or discrepancies remain undetected.
In general, the NHEFS data management team has not attempted to resolve
substantive data discrepancies that may exist 1) within the 1992 NHEFS data
tapes, or 2) between the 1992 NHEFS data tapes and the data tapes of the
original National Health and Nutrition Examination Survey (NHANES I) and/or
other NHEFS followup waves.
INTRODUCTION TO THE 1992 NHEFS MORTALITY DATA TAPE DOCUMENTATION
The NHANES I Epidemiologic Followup Study (NHEFS) is a longitudinal study
which uses as its baseline those adult persons ages 25 to 74 years who were
examined in the first National Health and Nutrition Examination Survey
(NHANES I). The NHEFS is comprised of a series of four followup surveys. The
first wave of data collection, the 1982-84 NHEFS, was conducted from 1982 to
1984 and included all persons who were between 25 and 74 years at their NHANES
I examination (n=14,407). The second wave of data collection, the 1986 NHEFS,
was conducted for members of the NHEFS cohort who were 55-74 years at their
baseline examination and not known to be deceased at the 1982-84 NHEFS
(n=3,980). The third wave, the 1987 NHEFS, was conducted for the entire non-
deceased NHEFS cohort (n=11,750). The fourth wave of data collection, the
1992 NHEFS, includes the entire non-deceased NHEFS cohort (n=11,195).
NHANES I collected data from a national probability sample of the United
States civilian noninstitutionalized population between the ages of 1 and 74
years. The survey, which included a standardized medical examination and
questionnaires that covered various health-related topics, took place from
1971 through 1974 and was augmented by an additional national sample in
1974-75. The NHANES I sample included 20,729 persons 25 to 74 years of age,
of whom 14,407 (70 percent) completed a medical examination. The design,
content and operation of NHANES I has been described elsewhere (Vital and
Health Statistics, Series 1, Nos. 10a, 10b, and 14).
Although NHANES I provided a wealth of information on the prevalence of health
conditions and risk factors, the cross-sectional nature of the original survey
limits its usefulness for studying the effects of clinical, environmental, and
behavioral factors and in tracing the natural history of disease. Therefore,
the NHEFS was designed to investigate the association between factors measured
at the baseline and the development of specific health conditions. It
originated as a joint project between the National Center for Health
Statistics (NCHS) and the National Institute on Aging with collaboration from
components of the National Institutes of Health and other Public Health
Service agencies. The 14,407 participants who were 25 to 74 years of age when
they were examined in NHANES I (1971-75) were included in the followup study
population.
In the first wave, the 1982-84 NHEFS, data were collected on all 14,407
subjects (i.e., individuals examined at NHANES I) in the cohort. Tracing of
subjects began in 1981 and data collection was conducted from 1982 to 1984.
Approximately 93 percent (n=13,383) of the cohort was successfully traced by
the end of the survey period. Detailed information on the design, content,
and operation of the 1982-84 NHEFS may be found in the Plan and Operation of
the NHANES I Epidemiologic Followup Study 1982-84, Vital and Health
Statistics, Series 1, No. 22. The basic design of the 1982-84 NHEFS consisted
of the following components:
-- tracing subjects or their proxies to a current address;
-- acquiring death certificates for deceased subjects;
-- performing in-depth interviews with the subjects or with their
proxies including, for surviving subjects, taking pulse, blood
pressure, and weight measurements of subjects; and,
-- obtaining hospital and nursing home records, including pathology
reports and electrocardiograms.
The second wave of NHEFS, the 1986 NHEFS, was conducted to assess changes in
the health and functional status of the oldest members of the NHEFS cohort
since the last contact period. It included 5,677 subjects who were 55 years
or older at their NHANES I examination (almost 40 percent of the entire NHEFS
cohort). Data collection was restricted to 3,980 subjects aged 55 years or
older at NHANES I who were not known to be deceased at the time of the 1982-84
NHEFS, regardless of their tracing or interview status in 1982-84. The
remaining 1,697 subjects who were deceased at the time of the 1982-84 NHEFS
were excluded from additional data collection in the 1986 NHEFS. Detailed
information on the design, content, and operation of the 1986 NHEFS may be
found in the Plan and Operation of the NHANES I Epidemiologic Followup Study,
1986, Vital and Health Statistics, Series 1, No. 25.
The 1987 NHEFS, the third wave of data collection, was conducted to continue
to collect information on changes in the health and functional status of the
NHEFS cohort since the last contact period. Tracing and data collection were
conducted during this followup survey only for the members of the NHEFS cohort
who had not been identified as deceased in 1982-84 or 1986 (n=11,750)
regardless of their previous tracing or interview status. The 2,657
previously deceased subjects were excluded from further data collection in the
1987 NHEFS. Detailed information on the design, content, and operation of the
1987 NHEFS may be found in the Plan and Operation of the NHANES I
Epidemiologic Followup Study, 1987, Vital and Health Statistics, Series 1, No.
27.
The fourth wave of the NHEFS, the 1992 NHEFS, collected information on changes
in the health and functional status of the NHEFS cohort since the last
contact. The 1992 NHEFS cohort includes 3,212 subjects who were deceased at
the time of the 1982-84, 1986 and 1987 NHEFS and 11,195 subjects who were not
known to be deceased prior to the 1992 NHEFS data collection period. Tracing
and data collection in the 1992 NHEFS was undertaken only for the non-deceased
subjects, regardless of their tracing or interview status in previous surveys.
The 3,212 previously deceased subjects were excluded from additional data
collection in the 1992 NHEFS. Detailed information on the design, content,
and operation of the 1992 NHEFS may be found in the Plan and Operation of the
NHANES I Epidemiologic Followup Study, 1992, Vital and Health Statistics,
Series 1, No. 35.
The design and data collection procedures adopted in the 1992 NHEFS were very
similar to the ones developed in the previous surveys: subjects were traced;
subject and proxy interviews were conducted; and, health care facility
abstracts and death certificates were collected. All subjects whose vital
status was not obtained through tracing procedures were considered lost-to-
followup in the 1992 NHEFS. In some cases, information about the death of a
subject was obtained from a former neighbor, a relative or another tracing
source. Although this information was noted in the subject's tracing record,
he or she was considered lost-to-followup unless the information was verified
by means of a death certificate or proxy interview. A subject's death had to
be confirmed by either a death certificate or proxy interview.
In addition to verifying the subject's vital status, the tracing process also
was used to obtain the current address of surviving subjects as well as to
identify a knowledgeable proxy respondent for deceased subjects. Respondents
who were identified and located through the tracing procedures were asked to
participate in a telephone interview. In a few cases, subjects who had been
traced successfully could not be relocated for the interview. Only their
vital status and the date when they were last traced in the 1992 survey are
available.
A major difference between the NHEFS waves was the manner in which the
interviews were conducted. In the 1982-84 NHEFS, the two-hour subject
interview was usually conducted in-person while, in subsequent followups, the
interview was shortened to approximately 30 minutes in length and was
conducted primarily by telephone. In addition, since the questionnaire was
not administered in-person, no physical measurements were made in the later
followups.
The 1992 NHEFS interviews were conducted over the telephone using a Computer
Assisted Telephone Interviewing (CATI) system. CATI is a telephone
interviewing technique that allows the interviewer to enter the answers
supplied by the respondent directly into the computer. Thus, editing and
coding time is reduced and keypunching from a hard copy questionnaire is
eliminated. A computer program drives the questionnaire so that the correct
skip patterns are followed and the appropriate questions are displayed on the
computer monitor. The skip patterns are based on information gathered from
previous data collection waves or on responses provided during the 1992
interview. For example, certain questions on pregnancy and menstrual history
in the 1992 interview were programmed to be skipped automatically if the
subject was male or if the female subject was interviewed previously and was
45 years of age or older at the time of that interview. Edit and logic checks
are incorporated into the data collection system itself, thus improving the
quality of the data.
As of July 19, 1993, the end of the 1992 NHEFS data collection period, 10,079
(90.0 percent) of the 11,195 members of the 1992 NHEFS cohort had been
successfully traced. Interviews were conducted for 9,281 subjects (92.1
percent of those successfully traced). In addition, 10,535 facility stay
records were collected for 4,162 subjects using information obtained from the
interview, death certificate, or some other source. Death certificates were
obtained for 1,374 (98.7 percent) of the 1,392 subjects who were known to have
died since last contact. Detailed information on the design, content, and
operation of the 1992 NHEFS may be found in the Plan and Operation of the
NHANES I Epidemiologic Followup Study 1992, Vital and Health Statistics,
Series 1, No. 35.
The data collected from the 1992 NHEFS are stored on four separate tapes:
1) Vital and Tracing Status tape -- contains summary information
about the status of the entire NHEFS cohort,
2) Interview tape -- contains the data collected from the subject and
proxy interviews,
3) Health Care Facility Stay tape -- contains information on reports
of stays in hospitals and nursing homes as well as information
abstracted from facility medical records,
4) Mortality Data tape -- contains data abstracted from the death
certificates from all three NHEFS surveys. This tape is discussed
below in more detail.
There are 4,497 records on the 1992 NHEFS Mortality Data Public Use tape.
It contains the death certificate information for all subjects who were
identified as deceased in either the 1982-84, 1986, 1987, or 1992 NHEFS and
for whom a death certificate was obtained. Positions 3-7 contain the Sample
Sequence Number, which is the subject identification number. This number is
unique for each subject and is used when linking files. By using the Sample
Sequence Number, the NHEFS 1992 Followup Mortality Data tape can be linked to
all other NHEFS and NHANES I data tapes.
The layout of this tape is identical to the layout used for the previous NHEFS
Mortality Data Public Use tapes. The source flag variable located in position
18 indicates the survey in which the subject was identified as deceased and
when his or her death certificate was received. Records with a source code of
1 identify 1982-84 Followup decedents whose death certificates were received
during the 1982-84 NHEFS data collection period. (Several data items on one
of the records from the 1982-84 tape have been updated on this file based on
data collected since the release of the 1982-84 NHEFS Mortality Public Use
tape.) A source code of 2 identifies 1982-84 Followup decedents whose death
certificates were received after the end of the 1982-84 survey period.
Records with a source code of 3 identify 1986 Followup decedents whose death
certificates were received during the 1986 NHEFS data collection period. A
source code of 4 is assigned to subjects who were first identified as deceased
in the 1987 NHEFS and whose death certificates were obtained during that
Survey. Records with a source code of 5 identify 1992 Followup decedents
whose death certificates were received during the 1992 NHEFS data collection
period. Lastly, a source code of 6 identifies 1987 Followup decedents whose
death certificates were received after the end of the 1987 survey period.
The 1992 NHEFS Mortality Data Public Use tape follows the coding
specifications used for the NCHS Multiple Cause-of-Death Public Use Data
tapes. No attempts have been made to resolve any discrepancies that may exist
between the demographic information coded on this data tape and the
information from other NHEFS or NHANES I data tapes.
An asterisk next to variables listed in the record layout documentation
indicates that the variable was computer-generated. All other variables
(excluding Sample Sequence Number) are extracted directly from the subject's
death certificate.
A change occurred in the geographic coding from the death certificate after
the close of the 1982-84 NHEFS survey period. If the Death Certificate Source
Flag in position 18 is coded 1, the Population Size of City of Residence and
Metropolitan-Nonmetropolitan County of Residence variables coded in positions
39 and 40, respectively, are based on data from the 1970 Census. If the Death
Certificate Source Flag is coded 2 through 5, then these two place of
residence variables are based on data from the 1980 Census. If the Death
Certificate Source Flag is coded 6 then these variables are based on data from
the 1990 Census.
NCHS Procedures Used to Code Multiple Cause Data
The original scheme for coding conditions listed on the death certificate was
designed with two objectives in mind. First, to facilitate etiological
studies of the relationships among conditions, it was necessary to reflect
accurately, in coded form, each condition and its location on the
certification in the exact manner given by the certifier. Secondly, the
codification needed to be carried out in a manner by which the underlying
cause-of-death could be assigned through computer applications. The approach
was to suspend the linkage provisions of the ICD for the purpose of condition
coding and code each entity with minimum regard to other conditions present on
the certification. This general approach is hereafter called entity coding.
Unfortunately, the set of multiple cause codes produced by entity coding is
not conducive to a third objective--the generation of person-based multiple
cause statistics. Person-based analysis requires that each condition be coded
within the context of every other condition on the same certificate and
modified or linked to such conditions as provided by ICD-9. By definition,
the entity data cannot meet this requirement since the linkage provisions
distort the character and placement of the information originally recorded by
the certifying physician.
Since the two objectives are incompatible, the Division of Vital Statistics
(DVS) at the National Center for Health Statistics chose to create from the
original set of entity codes a new code set called record axis multiple cause
data. Essentially, the axis of classification has been converted from an
entity basis to a record (or person) basis. The record axis codes are
assigned in terms of the set of codes that best describe the overall medical
certification portion of the death certificate. The translation is
accomplished by a computer system called TRANSAX (TRANSLATION OF AXIS) through
selective use of traditional linkage and modification rules for mortality
coding. Underlying cause linkages which simply prefer one code over another
for purposes of underlying cause selection are not included. Each entity code
on the record is examined and modified or deleted as necessary to create a set
of codes which are free of contradictions and are the most precise within the
constraints of ICD-9 and medical information on the record. Repetitive codes
are deleted. The process may (1) combine two entity axis categories together
to a new category thereby eliminating a contradiction or standardizing the
data; or (2) eliminate one category in favor of another to promote specificity
of the data or resolve contradictions. The following examples from ICD-9
illustrate the effect of this translation:
Case 1: When reported on the same record as separate entities,
cirrhosis of liver and alcoholism are coded to 5715
(cirrhosis of liver without mention of alcohol) and 303
(alcohol dependence syndrome). Tabulation of records with
5715 would on the surface falsely imply that such records
had no mention of alcohol. A preferable codification would
be 5712 (alcoholic cirrhosis of liver) in lieu of both 5715
and 303.
Case 2: If "gastric ulcer" and "bleeding gastric ulcer" are reported
on a record they are coded to 5319 (gastric ulcer,
unspecified as acute or chronic, without mention of
hemorrhage or perforation) and 5314 (gastric ulcer, chronic
or unspecified, with hemorrhage). A more concise
codification would be to code 5314 only since the 5314 shows
both the gastric ulcer and the bleeding.
A. Entity Axis Codes
The original conditions coded for selection of the underlying
cause-of-death are reformatted and edited prior to creating the public
use tape. The following paragraphs describe the format and application
of entity axis data.
FORMAT: Each entity-axis code is displayed as an overall seven byte
code with subcomponents as follows:
1. line indicator: The first byte represents the line of the
certificate on which the code appears.
Six lines (1-6) are allowable with the
fourth and fifth denoting one or two
written in "due to"s beyond the three
lines provided in Part I of the U.S.
standard death certificate. Line "6"
represents Part II of the certificate.
2. position indicator: The next byte indicates the position
of the codes on the line, i.e., it
is the first (1), second (2),
---eighth (8) code on the line.
3. cause category: The next four bytes represent the ICD-9
cause code.
4. nature of injury flag: ICD-9 uses the same series of numbers
(800-999) to indicate nature of injury (N
codes) and external cause codes (E codes).
This flag distinguishes between the two
with a one (1) representing nature of
injury codes and a zero (0) representing
all other cause codes.
A maximum of 20 of these seven byte codes is captured on a record for
multiple cause purposes. This may consist of a maximum of 8 codes on
any given line with up to 20 codes distributed across three or more
lines depending on where the subject conditions are located on the
certificate. Codes may be omitted from one or more lines, e.g., line 1
with one or more codes, line 2 with no codes, line 3 with one or more
codes.
In writing out these codes, they are ordered as follows: line 1 first
code, line 1 second code, etc. ----- line 2 first code, line 2 second
code, etc. ----- line 3 ----- line 4 ----- line 5 ----- line 6. Any
space remaining in the field is left blank.
EDIT: The original conditions are edited to remove invalid codes,
reverify the coding of certain rare causes of death, and assure
age/cause and sex/cause compatibility. Detailed information relating to
the edit criteria and the sets of cause codes which are valid to
underlying cause coding and multiple cause coding are provided in Part
11 of the NCHS Vital Statistics Instructions Manual Series.
ENTITY AXIS APPLICATIONS: The entity axis multiple cause data set is
appropriate to analyses which require that each condition be coded as a
stand alone entity without linkage to other conditions and/or require
information on the placement of such conditions in the certificate.
Within this framework, the entity data are appropriate to the
examination of etiological relationships among conditions, accuracy of
certification reporting, and the validity of traditional assumptions in
underlying cause selection. Additionally, the entity data provide in
certain categories a more detailed code assignment which is linked out
in the creation of record axis data. Where such detail is needed for a
study, the user should selectively employ entity data. Finally, the
researcher may not wish to be bound by the assumptions used in the axis
translation process preferring rather to investigate hypotheses of his
own predilection.
By definition, the main limitation of entity axis data is that an entity code
does not necessarily reflect the best code for a condition when considered
within the context of the medical certification as a whole. As a result
certain entity codes can be misleading or even contradict other codes in the
record. For example, category 5750 is titled "Acute cholecystitis without
mention of calculus." Within the framework of entity codes this is
interpreted to mean that the codable entity itself contained no mention of
calculus rather than that calculus was not mentioned anywhere on the record.
Tabulation of records with a "5750" as a count of persons having acute
cholecystitis without mention of calculus would therefore be erroneous. This
illustrates the fact that under entity coding the ICD-9 titles cannot be taken
literally. The user must study the rules for entity coding as they relate to
his/her research prior to utilization of entity data. The user is further
cautioned that the inclusion notes in ICD-9 which relate to modifying and
combining categories are seldom applicable to entity coding (except where
provided in Part 2b of the Vital Statistics Instruction Manual Series).
In tabulating the entity axis data, one may count codes with the resultant
tabulation of an individual code representing the number of times the
disease(s) represented by the code appears in the file. In this kind of
tabulation of morbid condition prevalence, the counts among categories may be
added together to produce counts for groups of codes. Alternatively, subject
to the limitations given above one may count persons having mention of the
disease represented by a code or codes. In this instance it is not correct to
add counts for individual codes to create person counts for groups of codes.
Since more than one code in the researcher's interest may appear together on
the certificate, totaling must account for higher order interactions among
codes. Up to 20 codes may be assigned on a record; therefore, a 20-way
interaction is theoretically possible. All totaling must be based on mention
of one or more of the categories under investigation.
B. Record Axis Codes
The following paragraphs describe the format and application of
record-axis data. Part 2f of the Vital Statistics Instruction Manual
Series describes the TRANSAX process for creating record axis data from
entity axis data.
FORMAT: Each record (or person) axis code is displayed in five bytes.
Locational information is not relevant. The code consists of
the following components:
1. cause category: The first four bytes represent the ICD-9
cause code.
2. nature of injury flag: The last byte contains a 0 or 1 with the 1
indicating that the cause is a nature of
injury category.
Again, a maximum of 20 codes are captured on a record for multiple cause
purposes.
EDIT: The record axis codes are edited for rare causes and age/cause
and sex/cause compatibility. Likewise, individual code validity is
checked. The valid code set for record axis coding is the same as that
for entity coding.
RECORD AXIS APPLICATIONS: The record axis multiple cause data set is
the basis for NCHS core multiple cause tabulations. Location of codes
is not relevant to this data set and conditions have been linked into
the most meaningful categories for the certification. The most
immediate consequences for the user is that the codes on the record
already represent mention of a disease assignable to that particular
ICD-9 category. This is in contrast to the entity code which is
assigned each time such a disease is reported on two different lines of
the certification. Secondly, the linkage implies that within the
constraints of ICD-9 the most meaningful code has been assigned. The
translation process creates for the user a data set which is edited for
contradictions, duplicate codes, and imprecisions. In contrast to
entity axis data, record axis data are classified in a manner comparable
to underlying cause of death classification thereby facilitating joint
analysis of these variables. Likewise, they are comparable to general
morbidity coding where the linkage provisions of ICD-9 are usually
utilized. A potential disadvantage of record axis data is that some
detail is sacrificed in a number of the linkages.
The user can take the record axis code as literally representing the
information conveyed in ICD-9 category titles. While knowledge of the rules
for combining and linking and coding conditions is useful, it is not a
prerequisite to meaningful analysis of the data as long as one is willing to
accept the assumptions of the axis translation process. The user is
cautioned, however, that due to special rules in mortality coding, not all
linkage notes in ICD-9 are utilized. (See Part 2f of the Vital Statistics
Instruction Manual Series.)
The user should proceed with caution in using record axis data to count
conditions as opposed to people with conditions since linkages have been
invoked and duplicate codes have been eliminated. As with entity data,
person-based tabulations which combine individual cause categories must take
into account the possible interaction of up to 20 codes on a single
certificate.
If on the surface it is not obvious whether entity axis or record axis data
should be employed in a given application, detailed examination of Part 2f of
the Vital Statistics Instruction Manual Series and its attachments will
probably provide the necessary information to make a decision. It allows the
user to determine the extent of the trade-offs between the two sets of data in
terms of specific categories and the assumptions of axis translation. In
certain situations, a combination of entity and record axis data may be the
more appropriate alternative.
Additional Reference Documents
The following documents provide detailed information on the rules employed for
coding multiple cause of death information from death certificate records:
1. Manual of the International Statistical Classification of
Diseases, Injuries, and Causes of Death: Based on the
Recommendations of the Ninth Revision Conference, 1975, and
Adopted by the Twenty-ninth World Health Assembly, Volumes 1 and
2, 1977 (World Health Organization).
2. NCHS Instruction Manual Data Preparation Part 2a, Vital Statistics
Instructions for Classifying the Underlying Cause of Death, 1979.
3. NCHS Instruction Manual Data Preparation, Part 2b, Vital
Statistics Instructions for Classifying Multiple Causes of Death,
1979.
4. NCHS Instruction Manual Data Preparation, Part 2c, Vital
Statistics ICD-9 ACME Decision Tables for Classifying Underlying
Causes of Death, 1979.
5. NCHS Instruction Manual Data Preparation, Part 2f, Vital
Statistics ICD-9 TRANSAX Disease Reference Tables for Classifying
Multiple Causes of Death, 1981.
Data Tape Characteristics
Data Set Name: NHEFS3.MORT87PB
Record Length: 440
Blocksize: 32560
Number of Records: 4,497
Number of Reels: 1
Recording Mode: FIXED BLOCK, EBCDIC
Density: 6250 bpi
Channel: 9 TRACK
Created by: Office of Analysis and Epidemiology
Division of Epidemiology
National Center for Health Statistics
Presidential Building, Room 730
6525 Belcrest Road
Hyattsville, Maryland 20782
RECORD LAYOUT
Tape
Data Items
Positions
1. Sample Sequence Number 3-7
2. General
a. Year of death 1-2
b. Death certificate source flag
18
c. Record type 19
d. Resident status 20
e. Month of death 55-56
f. Day of death 57-58
3. Occurrence
a. Region 26
b. Division 27
c. Place of death--hospital and status 75
4. Residence
a. Population size of city of residence 39
b. Metropolitan/nonmetropolitan county 40
c. Region 41
d. Division 42
5. The Decedent
a. Sex 59
b. Race 60-63
c. Age 64-72
d. Marital status 77
6. Underlying Cause
a. ICD-9 code 142-145
b. 282 cause recode 146-150
c. 72 cause recode 151-153
d. 34 cause recode 157-159
e. Autopsy performed 84
f. Place of accident for causes E850-E929 141
7. Multiple Conditions
a. Entity-Axis conditions
1. Number of 160-161
2. The conditions 162-301
b. Record-Axis conditions
1. Number of 338-339
2. The conditions 341-440
1-2 2 Year of Death
71-93 ... Year of death (1971-1993)
(Note: Month and Day of Death are stored in tape locations 55-56
and 57-58, respectively.)
3-7 5 Sample Sequence Number
8-17 2 Blank
18 1 Death Certificate Source Flag (*)
1 ... Death certificate received for 1982-84
NHEFS decedent in the 1982-84 NHEFS period
2 ... Death certificate received for 1982-84 NHEFS decedent
after the 1982-84 NHEFS period
3 ... Death certificate received for 1986 NHEFS
decedent in the 1986 NHEFS period
4 ... Death certificate received for 1987 NHEFS decedent
in the 1987 NHEFS period
5 ... Death certificate received for 1992 NHEFS
decedent in the 1992 NHEFS period
6 ... Death certificate received for 1987 NHEFS
decendent after the 1987 NHEFS period
19 1 Record Type (*)
1 ... RESIDENT
State and County of Occurrence and
Residence are the same.
2 ... NONRESIDENT
State and/or County of Occurrence and
Residence are different.
_____________________
*) indicates that the variable was computer-generated. All other variables
(excluding Sample Sequence Number) are extracted directly from the subject's
death certificate.
20 1 Resident Status (*)
1 ... RESIDENT
State and County of Occurrence and
Residence are the same.
2 ... INTRASTATE NONRESIDENT
State of Occurrence and Residence are the
same, but County is different.
3 ... INTERSTATE NONRESIDENT
State of Occurrence and Residence are
different, but both are in the U.S.
4 ... FOREIGN RESIDENT (OCCURRENCE IS IN THE
U.S.)
State of Occurrence is one of the 50
States or the District of Columbia, but
Place of Residence is outside of the U.S.
Blank ... PLACE OF OCCURRENCE IS OUTSIDE THE U.S.
21-25 5 Blank
26-27 2
Region (*) and Division (*) of Occurrence of Death
Position 26 is Region. Position 27 is Division. Divisions are
coded within Region and States are coded within Division. The
code structure is designed to sequence the states as they appear
in NCHS publications.
Loc. Loc.
26 27
0 0 ... OCCURRENCE IS OUTSIDE THE U.S.
1 ... NORTHEAST
1 ... New England
... Maine
... New Hampshire
... Vermont
... Massachusetts
... Rhode Island
... Connecticut
2 ... Middle Atlantic
... New York
... New Jersey
... Pennsylvania
27 2 Region (*) and Division (*) of Occurrence of Death --
Continued
Loc. Loc.
26 27
2 ... MIDWEST
3 ... East North Central
... Ohio
... Indiana
... Illinois
... Michigan
... Wisconsin
4 ... West North Central
... Minnesota
... Iowa
... Missouri
... North Dakota
... South Dakota
... Nebraska
... Kansas
3 ... SOUTH
5 ... South Atlantic
... Delaware
... Maryland
... District of Columbia
... Virginia
... West Virginia
... North Carolina
... South Carolina
... Georgia
... Florida
6 ... East South Central
... Kentucky
... Tennessee
... Alabama
... Mississippi
7 ... West South Central
... Arkansas
... Louisiana
... Oklahoma
... Texas
26-27 2 Region (*) and Division (*) of Occurrence of Death--
Continued
Loc. Loc.
26 27
4 ... WEST
8 ... Mountain
... Montana
... Idaho
... Wyoming
... Colorado
... New Mexico
... Arizona
... Utah
... Nevada
9 ... Pacific
... Washington
... Oregon
... California
... Alaska
... Hawaii
28-38 11 Blank
39 1 Population Size of City of Residence (*)
0 ... Place of 1,000,000 or more persons
1 ... Place of 500,000 to 1,000,000 persons
2 ... Place of 250,000 to 500,000 persons
3 ... Place of 100,000 to 250,000 persons
4 ... Place of 50,000 to 100,000 persons
5 ... Place of 25,000 to 50,000 persons
6 ... Place of 10,000 to 25,000 persons
9 ... All other areas in the U.S.
Z ... Foreign resident
(Note: If position 18 is coded 1, this variable is based on data
from the 1970 Census. If position 18 is coded 2 through 5 then
this variable is based on data from the 1980 Census. If position
18 is coded 6 then this variable is based on data from the 1990
Census.)
40 1 Metropolitan - Nonmetropolitan County of Residence (*)
1 ... Metropolitan county
2 ... Nonmetropolitan county
Z ... Foreign resident
9 ... Unknown
(Note: If position 18 is coded 1, this variable is based on data
from the 1970 Census. If position 18 is coded 2 through 5 then
this variable is based on data from the 1980 Census. If position
18 is coded 6 then this variable is based on data from the 1990
Census.)
41-42 2 Region (*) and Division (*) of Residence
Position 41 is Region. Position 42 is Division. Divisions are
coded within Region and States are coded within Division.
The code structure is designed to sequence the States as they
appear in NCHS publications.
Loc. Loc.
41 42
0 0 ... FOREIGN RESIDENT
1 ... NORTHEAST
1 ... New England
... Maine
... New Hampshire
... Vermont
... Massachusetts
... Rhode Island
... Connecticut
2 ... Middle Atlantic
... New York
... New Jersey
... Pennsylvania
2 ... MIDWEST
3 ... East North Central
... Ohio
... Indiana
... Illinois
... Michigan
... Wisconsin
41-42 2 Region (*) and Division (*) of Residence -- Continued
Loc. Loc.
41 42
4 ... West North Central
... Minnesota
... Iowa
... Missouri
... North Dakota
... South Dakota
... Nebraska
... Kansas
3 ... SOUTH
5 ... South Atlantic
... Delaware
... Maryland
... District of Columbia
... Virgin
... West Virginia
... North Carolina
... South Carolina
... Georgia
... Florida
6 ... East South Central
... Kentucky
... Tennessee
... Alabama
... Mississippi
7 ... West South Central
... Arkansas
... Louisiana
... Oklahoma
... Texas
4 ... WEST
8 ... Mountain
... Montana
... Idaho
... Wyoming
... Colorado
... New Mexico
... Arizona
... Utah
... Nevada
41-42 2 Region (*) and Division (*) of Residence -- Continued
Loc. Loc.
41 42
9 ... Pacific
... Washington
... Oregon
... California
... Alaska
... Hawaii
43-51 9 Blank
52-53 2 Education
00 ... No formal education
01-08 ... Years of elementary school
09 ... 1 year of high school
10 ... 2 years of high school
11 ... 3 years of high school
12 ... 4 years of high school
13 ... 1 year of college
14 ... 2 years of college
15 ... 3 years of college
16 ... 4 years of college
17 ... 5 or more years of college
99 ... Not stated
(Note: This information is only available for deaths occurring in
1989 and later. For earlier years, this field will be blank.)
54 1 Education Recode
1 ... 0 - 8 years
2 ... 9 - 11 years
3 ... 12 years
4 ... 13 - 15 years
5 ... 16 years or more
6 ... Not stated
(Note: This information is only available for deaths occurring in
1989 and later. For earlier years, the field will be blank.)
(55-58) 4 DATE OF DEATH
(Note: Year of Death is given in tape locations 1-2)
55-56 2 Month
01 ... January
02 ... February
03 ... March
04 ... April
05 ... May
06 ... June
07 ... July
08 ... August
09 ... September
10 ... October
11 ... November
12 ... December
57-58 2 Day
01-31 ... As applicable to Month of Death
99 ... Not stated
59 1 Sex
1 ... Male
2 ... Female
(60-63) 4 RACE
SPECIAL INSTRUCTION: For deaths occurring in 1988 and
earlier, use definition (a). For deaths occurring in 1989
and later, use definition (b). The two definitions are a
result of a change in coding rules.
60-61 2 Detail Race (a)
00 ... Other Asian or Pacific Islander
01 ... White
02 ... Black
03 ... American Indian (includes Aleuts and
Eskimos)
04 ... Chinese
05 ... Japanese
06 ... Hawaiian (includes Part-Hawaiian)
07 ... All other races
08 ... Filipino
60-61 1 Detail Race (b)
01 ... White
02 ... Black
03 ... American Indian (includes Aleuts and
Eskimos)
04 ... Chinese
05 ... Japanese
06 ... Hawaiian(includes Part-Hawaiian)
07 ... Filipino
08 ... Other Asian or Pacific Islander
09 ... All other races
62 1 Race Recode #1 (*)
1 ... White
2 ... Races other than white or black
3 ... Black
63 1 Race Recode #2 (*)
1 ... White
2 ... All other races
(64-72) 9 AGE OF DEATH
(Note: The age at death listed on the death certificate
is often incorrect due to erroneous information provided
by the informant. The NHEFS team suggests that the analyst
use the computer-generated Age at Death variable in positions
67-68 on the 1992 NHEFS Vital and Tracing Status Public Use
data tape, which is based on the Date of Death and the NHEFS
Date of Birth.)
64-66 3 Detail Age at Death
029-097 ... Age in years (not inclusive)
999 ... Age not stated
(Note: A leading zero in position 64 indicates that the
subject was less than 100 years old at Date of Death.)
67-68 2 Age of Death Recode #1 (*)
31 ... 25 - 29 years
32 ... 30 - 34 years
33 ... 35 - 39 years
34 ... 40 - 44 years
35 ... 45 - 49 years
36 ... 50 - 54 years
37 ... 55 - 59 years
38 ... 60 - 64 years
39 ... 65 - 69 years
40 ... 70 - 74 years
41 ... 75 - 79 years
42 ... 80 - 84 years
43 ... 85 - 89 years
44 ... 90 - 94 years
45 ... 95 - 99 years
46 ... 100 - 104 years
47 ... 105 - 109 years
48 ... 110 - 114 years
49 ... 115 - 119 years
50 ... 120 - 124 years
51 ... 125 years and over
52 ... Age not stated
69-70 2 Age of Death Recode #2 (*)
11 ... 25 - 29 years
12 ... 30 - 34 years
13 ... 35 - 39 years
14 ... 40 - 44 years
15 ... 45 - 49 years
16 ... 50 - 54 years
17 ... 55 - 59 years
18 ... 60 - 64 years
19 ... 65 - 69 years
20 ... 70 - 74 years
21 ... 75 - 79 years
22 ... 80 - 84 years
23 ... 85 - 89 years
24 ... 90 - 94 years
25 ... 95 - 99 years
26 ... 100 years and over
27 ... Age not stated
71-72 2
Age of Death Recode #3 (*)
05 ... 25 - 34 years
06 ... 35 - 44 years
07 ... 45 - 54 years
08 ... 55 - 64 years
09 ... 65 - 74 years
10 ... 75 - 84 years
11 ... 85 years and over
12 ... Age not stated
73-74 2 Blank
(75) SPECIAL INSTRUCTION: for deaths occurring in 1988 and
earlier, use definition (a). For deaths occurring in
1989 and later, use definition (b). The two definitions
are a result of a change in coding rules.
75 1 (a) Place of Death -- Hospital and Status
1 ... Hospital, clinic or medical center
- Inpatient
2 ... Hospital, clinic or medical center
- Outpatient or admitted to emergency
room
3 ... Hospital, clinic or medical center
- Dead on arrival
4 ... Hospital, clinic or medical center
- Patient status unknown
5 ... Hospital, clinic or medical center
- Patient status not on certificate
6 ... Other institutions providing patient
care
7 ... All other reported entries
8 ... Dead on arrival
- Hospital, clinic or medical center name
not given
9 ... Hospital and patient status not stated
(b) Place of Death -- Decedent's Status
1 ... Hospital, clinic or medical center
- Inpatient
2 ... Hospital, clinic or medical center
- Outpatient or admitted to emergency
room
3 ... Hospital, clinic or medical center
- Dead on arrival
4 ... Hospital, clinic or medical center
- Patient status unknown
5 ... Nursing home
6 ... Residence
7 ... Other
9 ... Place of death unknown
76 1 Blank
77 1 Marital Status
1 ... Never married, single
2 ... Married
3 ... Widowed
4 ... Divorced
8 ... Marital status not on certificate
9 ... Marital status not stated
78-83 6 Blank
84 1 Autopsy Performed
1 ... Yes
2 ... No
8 ... Autopsy performed not on certificate
9 ... Autopsy performed not stated
85-140 56
Blank
141 1 Place of Accident for Causes E850-E929
0 ... Home
1 ... Farm
2 ... Mine and quarry
3 ... Industrial place and premises
4 ... Place for recreation and sports
5 ... Street and highway
6 ... Public building
7 ... Resident institution
8 ... Other specified place
9 ... Place of accident not specified
Blank ... Causes other than E850-E929
(142-159) 18 UNDERLYING CAUSE OF DEATH
142-145 4 ICD Code (9th Revision)
See the Manual of the International Statistical
Classification of Diseases, Injuries, and Causes of
Death: Based on the Recommendations of the Ninth
Revision Conference, 1975, and Adopted by the Twenty-
ninth World Health Assembly, Volume 1, 1977 (World
Health Organization). For injuries and poisonings, the
external cause is coded (E800-E999) rather than the
Nature of Injury (800-999). These positions do not
include the letter E for the external cause of injury.
For those causes that do not have a 4th digit,
position 145 is blank.
146-150 5 Cause-of-Death Recode -- 282 Groups
A recode of the ICD-9 cause-of-death code into 282
groups for NCHS publications. See Appendix 1 for a
complete list of recodes and the causes included.
00100-35800 ... Code range (not inclusive)
151-153 3 Cause-of-Death Recode -- 72 Groups
A recode of the ICD-9 cause-of-death code into 72
groups for NCHS publications. See Appendix 2 for a
complete list of recodes and the causes included.
010-840 ... Code range (not inclusive)
154-156 3 Blank
157-159 3 Cause-of-Death Recode -- 34 Groups (*)
A recode of the ICD-9 cause code into 34 groups for
NCHS publications. See Appendix 3 for a complete list
of recodes and the causes included.
010-370 ... Code range (not inclusive)
(160-440) 281 MULTIPLE CONDITIONS
160-161 2 Number of Entity-Axis Conditions
01-20 ... Code range (not inclusive)
162-301 140 ENTITY - AXIS CONDITIONS
Space has been provided for maximum of 20 conditions.
Each condition takes 7 positions in the record.
Records that do not have 20 conditions are blank in the
unused area.
Position 1: Part/line number on certificate
1 ... Part I, line 1 (a)
2 ... Part I, line 2 (b)
3 ... Part I, line 3 (c)
4 ... Part I, line 4 (d)
5 ... Part I, line 5 (e)
6 ... Part II
Position 2: Sequence of condition within part/line
1-8 ... Code range
Positions 3 - 6: ICD-9 condition code
See the Manual of the International
Statistical Classification of Diseases,
Injuries, and Causes of Death: Based on the
Recommendations of the Ninth Revision
Conference, 1975, and Adopted by the Twenty-
ninth World Health Assembly, Volume 1, 1977
(World Health Organization) for a complete
list of codes.
Position 7: Nature of Injury Flag
1 ... Indicates that the code in
positions 3-6 is a Nature of
Injury code
0 ... All other codes
162-168 7 1st Condition
169-175 7 2nd Condition
176-182 7 3rd Condition
183-189 7 4th Condition
190-196 7 5th Condition
197-203 7 6th Condition
204-210 7 7th Condition
211-217 7 8th Condition
218-224 7 9th Condition
225-231 7 10th Condition
232-238 7 11th Condition
239-245 7 12th Condition
246-252 7 13th Condition
253-259 7 14th Condition
260-266 7 15th Condition
267-273 7 16th Condition
274-280 7 17th Condition
281-287 7 18th Condition
288-294 7 19th Condition
295-301 7 20th Condition
302-337 36 Blank
338-339 2 Number of Record-Axis Conditions
01-20 ... Code range (not inclusive)
340 1 Blank
(341-440) 100 RECORD - AXIS CONDITIONS
Space has been provided for a maximum of 20 conditions. Each
condition takes 5 positions in the record. Records that do not
have 20 conditions are blank in the unused area.
Positions 1 - 4: ICD-9 condition code
See the Manual of the International
Statistical Classification of Diseases,
Injuries, and Causes of Death: Based on the
Recommendations of the Ninth Revision
Conference, 1975, and Adopted by the Twenty-
ninth World Health Assembly, Volume 1, 1977
(World Health Organization) for a complete
list of codes.
Position 5: Nature of Injury Flag
1 ... Indicates that the code in
positions 1-4 is a Nature
of Injury code
0 ... All other codes
341-345 5 1st Condition
346-350 5 2nd Condition
351-355 5 3rd Condition
356-360 5 4th Condition
361-365 5 5th Condition
366-370 5 6th Condition
371-375 5 7th Condition
376-380 5 8th Condition
381-385 5 9th Condition
386-390 5 10th Condition
391-395 5 11th Condition
396-400 5 12th Condition
401-405 5 13th Condition
406-410 5 14th Condition
411-415 5 15th Condition
416-420 5 16th Condition
421-425 5 17th Condition
426-430 5 18th Condition
431-435 5 19th Condition
436-440 5 20th Condition
