Scientific Data Documentation
Epidemiologic Followup Study, 1992 Supplemental Health Care Facility Stay
ACKNOWLEDGMENTS
Overall responsibility for the data processing and the compilation and
documentation for the NHANES I Epidemiologic Followup Study (NHEFS), Supplemental
Health Care Facility Stay Public Use tape rested with Michael E. Mussolino.
Assistance was provided by other members of the NHEFS data management team:
Sandra T. Rothwell, Christine S. Cox, Jennifer H. Madans, Dawn M. Scott, Madelyn
A. Lane, Keith A. Zevallos, Joel C. Kleinman, Cynthia A. Reuben, Cordell W.
Golden 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 Westat, the
contractor who collected the data for this longitudinal study, 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 (NIH) and other Public Health Service agencies: the National Cancer
Institute; the National Institute of Child Health and Human Development; 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
NHANES I Epidemiologic Followup Study, Supplemental HCFS............. 3
NHEFS Supplemental HCFS Data Tape Characteristics.................... 7
NHEFS Supplemental Health Care Facility Stay Introduction............ 8
Medical Coding Specifications........................................ 12
NHEFS Supplemental HCFS Public Use Tape Documentation................ 17
Figure 1: Supplemental Health Care Facility Record Layout............ 31
Figure 2: Example of Matching Process and Record Status Codes........ 32
Appendix A: Record Status Codes...................................... 33
Appendix B: Numeric Codes for Reported Conditions.................... 34
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 NHEFS Supplemental 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, MD 20782
ERRORS IN THE 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 NHEFS Supplemental
data tape, or 2) between the NHEFS Supplemental data tape and the data tapes of
the original National Health and Nutrition Examination Survey (NHANES I) and
other NHEFS followup waves.
NHANES I EPIDEMIOLOGIC FOLLOWUP STUDY, SUPPLEMENTAL HCFS
I. NHEFS BACKGROUND INFORMATION
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 of data collection, the 1987 NHEFS, was conducted for the entire non-
deceased NHEFS cohort (n=11,750). The fourth wave of data collection, the 1992
NHEFS, was also conducted for the entire non-deceased NHEFS cohort (n=11,195).
This file documentation describes data collected for the Supplemental Health Care
Facility Stay (HCFS) file of the 1992 NHEFS.
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 the 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 designed 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 additional 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 1992 NHEFS, the fourth wave of data collection was designed 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, 1986 or 1987 (n=11,195) regardless of their
previous tracing or interview status. 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 NHEFS Supplemental Health Care Facility Stay file was created as a result of
the substantial number of out-of-scope abstracts received from facilities during
the 1992 NHEFS. These abstracts should have been received on an earlier NHEFS
wave. The large number of abstracts was partly due to the procedures instituted
for maximizing the collection of reports of hospital or nursing home stays, i.e.,
deliberately requesting out-of-scope report information. A total of 70 abstracts
were collected for 52 subjects. Thirty-nine of these abstract records replace
non-match records on the 1982-84, 1986 or 1987 NHEFS. These changes are
presented in the Table 1. For data analysis, the Supplemental file should used
in conjunction with one or more of the previous NHEFS Health Care Facility Stay
waves and not as the sole data source. The Supplemental HCFS file records
contain data from the first three NHEFS waves.
Table 1.
NHEFS Supplemental HCFS records which replace non-matched records on
previous waves.
Supplemental File Previous Wave
Sequence # Stay # Stay # Survey
04325 S0101 MAT 30203 XNS 87
04325 S0102 MAT 30204 XNS 87
04753 S0101 MAT 20101 ONR 86
04753 S0102 CRM 30301 CRX 87
05020 S0101 MAT 20101 ONR 86
05020 S0102 CRM 30301 CRX 87
05603 S0101 MAT 20102 REF 86
08011 S0101 MAT 10101 ANO 82-84
08011 S0102 MAT 10102 ANO 82-84
08394 S0101 MAT 20201 ONR 86
08404 S0101 MAT 20101 REF 86
08404 S0102 CRM 30301 CRX 87
10090 S0101 MAT 30401 XNH 87
11026 S0101 MAT 30201 XNS 87
13590 S0101 MAT 10101 XNH 82-84
13769 S0101 MAT 30101 XNH 87
14307 S0101 MAT 30101 REF 87
14929 S0101 MAT 30101 ABT 87
19586 S0101 MAT 30101 REF 87
19636 S0101 MAT 30101 REF 87
20410 S0101 MAT 30101 DKH 87
20598 S0101 MAT 30201 REF 87
20878 S0101 MAT 30104 XRD 87
20878 S0102 MAT 30103 XRD 87
20883 S0101 MAT 30101 XRD 87
20905 S0101 MAT 30101 XRD 87
20932 S0101 MAT 30101 XRD 87
20932 S0102 MAT 30102 XRD 87
20945 S0101 MAT 30102 XRD 87
20976 S0101 MAT 30102 XNH 87
21692 S0101 MAT 30101 XNH 87
21692 S0102 MAT 30102 XNH 87
21814 S0101 MAT 10201 XNS 82-84
21980 S0101 XNH 10101 XNH 82-84
21980 S0102 MAT 10201 XNS 82-84
22194 S0101 MAT 30101 REF 87
24256 S0101 MAT 10101 ONR 82-84
24256 S0102 CRM 20201 ONR 86
24256 S0103 CRM 30201 CRX 87
NHEFS SUPPLEMENTAL HEALTH CARE FACILITY STAY DATA TAPE CHARACTERISTICS
Title: NHEFS Supplemental Health Care Facility Stay Data Tape
Data Set Name: NHEFS4.HCFSUPPL.FINAL
Record Length: 429
Blocksize: 31746
Number of Records: 70
Recording/
Storage Media: FIXED BLOCK, EBCDIC/IBM 3480 Cartridge Tape
Created by: Office of Analysis, Epidemiology and Health Promotion
Division of Epidemiology
National Center for Health Statistics
Presidential Building, Room 730
6525 Belcrest Road
Hyattsville, Maryland 20782
NHEFS SUPPLEMENTAL HEALTH CARE FACILITY STAY INTRODUCTION
The 1982-84, 1986, 1987 and 1992 NHEFS Health Care Facility Stay files contain
information on overnight stays that are in-scope for each NHEFS period. The in-
scope period depends upon the timing of the subject's interviews and his/her
vital status. For example, among subjects who have not been interviewed since
the NHANES I exam, the 1992 in-scope period is from the date of the NHANES I exam
to the date of the 1992 interview for surviving subjects and from the exam date
to the date of death for deceased subjects. For subjects who have had at least
one followup interview prior to the 1992 followup, the in-scope period is from
the date of the last interview (either 1982-84, 1986 or 1987) to the date of the
1992 interview for surviving subjects and from the date of the last interview to
the date of death for deceased subjects. The in-scope period for other waves is
defined similarly. Stays that were reported prior to the in-scope period were
defined as out-of-scope for the 1992 survey. The Supplemental file contains
records that are out-of-scope for the 1992 followup, but in-scope for a previous
wave. These records have not been collected in prior waves. This file provides
the data user with access to information on overnight health care facility stays
that are not available on previously released data files.
Identification of Stay Reports:
Reports of overnight hospital or nursing home facility stays were obtained from
various sources. Most reports were elicited through a series of detailed
questions in section B of the interview. Generally, respondents were asked to
report all overnight facility stays since 1987 if the subject was last
interviewed in the 1987 NHEFS, since 1985 if the subject was last interviewed in
the 1986 NHEFS, since 1980 if the subject was last interviewed in the 1982-84
NHEFS, or since 1970 if the subject was last interviewed at NHANES I examination.
In addition to interview information, data on facility stays were gathered from
other reporting sources: from the death certificate, from other hospital
abstracts and from miscellaneous other sources. At the conclusion of the
interview, authorization was obtained for permission to contact facilities.
Facility Data Collection:
For each stay reported during the interview, the name and address of the
facility, the reported dates of the stay, and the reason for the stay were
recorded on the hospital and health care facility chart (HHCF). A separate log
book was kept containing similar data for reports gathered from the death
certificates, hospital abstracts and other sources. All reports of facility
stays were compiled and entered into a computerized tracking system. All
reported facilities were contacted by mail and asked to review the subject's
medical records and to abstract information on exact dates of admission,
discharge and diagnoses onto standard abstract forms. In addition to completing
abstract forms, facilities were requested to submit photocopies of selected
sections of the subject's inpatient record i.e., the "facesheet", the discharge
summary and of pathology reports (for any admission where a new malignancy was
diagnosed).
Matching Records:
As the abstracts were received, they were checked against report information in
the tracking system to determine if the abstract "matched" any of the reported
stays. Date of admission and diagnosis were used as matching criteria but exact
matches on date or diagnosis were not required for a stay to be considered
matched. Abstracts were matched to reports if the reported date of admission was
within a year of the actual date of admission and if the reported reason for
admission involved the same body system as at least one of the diagnoses present
on the abstract. Cases that did not meet these specific criteria were reviewed
by NCHS staff and matched when appropriate.
Each record on the file represents an overnight facility stay. Therefore, one
or more Supplemental records will exist for some subjects, while other subjects
will have no records on the file. The structure of the data file reflects the
system used to obtain and process stay information. The record is divided into
three major sections: 1) the report section, 2) the record status section and
3) the abstract section. An example of the record layout is provided in
figure 1.
The subject identification number (i.e. the sample sequence number) is in
positions 1-5 on each record. This number is unique for each subject and is used
when linking the Health Care Facility Stay tape to all other NHEFS and NHANES I
Public Use Data Tapes. The total number of records per subject is found in
positions 6-7 on the file. The first section of the record is the report section
(positions 29-59 and 63-204) which contains information from the reporting source
as well as stay identification numbers assigned by NCHS. Each stay entered into
the report section is assigned a health care facility stay id number (positions
29-33). When used in conjunction with the sample sequence number, this number
uniquely identifies each record on the file. The reported date of admission is
found in positions 47-52. This date is used in conjunction with the other
interview dates to determine in which followup wave the record should have
appeared.
The record status section (positions 60-62) contains a code for the result of an
abstract request. If a facility returned an abstract that matched a report from
a previous wave then a record status code of MAT (match) was applied. A returned
abstract that did not match any reports, either for 1992 or for any previous
waves and was out-of-scope for the 1992 survey period was assigned a record
status code of ASF (additional stay found). A record status code of CRM (cross-
referenced match) was applied to a stay that was the continuation of a stay begun
in a prior survey period.
The abstract section (positions 205-379) contains the information obtained from
the facility records including actual dates of admission, discharge and
diagnoses. The diagnoses on the abstracts were coded using the ICD-9-CM
according to the medical coding specifications detailed in the following section
of this codebook. The abstract section is similar to the original 1982-84 NHEFS
Health Care Facility record file released in August 1987.
Information will be present in one or more sections of the record depending on
whether a previous report had been obtained. The presence or absence of
information in the three sections results in two different record profiles.
Figure 2 illustrates these profiles. The first is the successfully matched stay
record, where an abstract was received which matched a report on a previous wave.
Refer to Table 1. Non-match reports on the 1982-84, 1986 and 1987 NHEFS were
compared to Supplemental file abstracts for possible matches. Records were
matched based on reported admission date, facility identification number and
reported conditions. Abstract information is added to the report and the code
of MAT was entered into the record status section. Complete information is
available in the first three sections of the record for these stays. The second
type of record is one which was generated solely by the receipt of a facility
abstract. This type of record resulted when the facility returned an out-of-
scope (for 1992) abstract that did not match with any report on 1992 or on a
previous wave. When this occurred, the abstract was entered on the file, and
stay identifiers were assigned in the report section of the record but no other
information in the report section is present. An ASF (additional stay found)
code was entered in the record status section.
In summary, the NHEFS Supplemental HCFS file contains records which could be
included with previous NHEFS waves in 1982-84, 1986 and 1987. The majority of
these abstracts replace previous non-matched records. For data users looking for
a specific medical condition, the Supplemental file should be appended to other
waves. The survey identifier in column 28 indicates the appropriate earlier
wave (1982-84, 1986 or 1987) where the record should have been collected.
Records with a discharge date of 979797 (still in facility) may be pointed to in
a later wave in columns 55-59 indicating that the stay overlaps with more than
one survey period.
MEDICAL CODING SPECIFICATIONS
Medical coding for the NHEFS Supplemental HCFS data tape was based on the
International Classification of Diseases-9th Revision-Clinical Modification (ICD-
9-CM). The health care facility was asked to abstract all diagnoses and
procedures onto a special form. In most cases, a copy of the hospital discharge
summary and/or medical records facesheet was attached to the abstract. The
diagnoses and procedures listed on the discharge summary or facesheet were then
compared with those provided on the abstract form. In most instances,
discrepancies were resolved by coding the diagnoses or procedures as provided on
the discharge summary or the facesheet.
All diagnoses were coded to the highest level of specificity possible. The
fourth-digit subcategory for diagnosis and procedure codes was used whenever
possible. The fifth-digit subclassification of disease for diagnosis codes was
also used when appropriate. A three-digit ICD code was used only if it could not
be further subdivided. The following rules were used to code diagnoses and
procedures.
Rules Governing Medical Coding of Diagnoses:
All medical diagnoses listed on the health care facility abstract form or the
discharge summary are coded by trained medical coders. The coders assigned the
principal diagnosis as the condition established after study to be chiefly
responsible for occasioning the admission of the patient to the health care
facility. The admitting diagnosis is not used as the principal diagnosis unless
the admitting and discharge diagnoses are the same.
Ex: Patient admitted with a diagnosis of bronchopneumonia. After workup
and treatment, x-ray findings, etc., the patient was discharged with a
final diagnosis of bronchopneumonia. The principal diagnosis is coded
485 for bronchopneumonia.
All other diagnoses or conditions existing at the time of admission or that
developed subsequently during the stay are coded.
Ex: Patient was admitted with a diagnosis of uncontrolled diabetes
mellitus, and during the course of examination and treatment, phlebitis
was discovered. The diabetes and the phlebitis are coded.
Diagnoses documented as probable, possible, suspected, question of, suggestive
of, compatible with, or questionable are coded and prefixed with a "P".
Ex: If the diagnosis is stated possible myocardial infarction, the
diagnosis code is P410.9.
If a diagnosis is stated as "rule out" or "R/O", the condition is coded as if it
exists and the "P" prefix is not used. If a diagnosis is stated as "ruled out",
the condition is not coded.
Ex: If "R/O M.I." appears on the facesheet, the code is 410.9
If "M.I. ruled out" appears, the condition is not coded.
Hospital acquired infections, such as a "staph" infection, if documented on the
facesheet and/or discharge summary are coded. Documentation may be in the form
of a note by the infections committee, stamped notation, or a checkmark,
depending on the record format.
Malignant neoplasms are coded according to ICD-9-CM coding specifications which
indicate primary site of origin.
Injuries and poisonings are coded, where applicable, using both the nature of the
injury and the external cause of injury code (E800-E999).
Ex: Patient sustained comminuted fracture of the femur due to a fall
down stairs. Nature of injury code is 821.00 and external cause of
injury code is E880.9
"History of" conditions are not coded with the following exceptions:
Old myocardial infarction (more than 8 weeks since last occurrence)
Status post bypass surgery
Malignant neoplasm (cancer in remission or under treatment)
Old cerebrovascular accident
Sterilization
Normal pregnancy undelivered
Manipulation of an IUD
These diagnoses are coded using "V" codes and were used on a limited basis.
Recurrent malignancy codes are prefixed with an "R".
Symptoms (ICD-9-CM codes 7800-7999) were coded using the following guidelines:
1. When the only diagnosis listed on the abstract form, facesheet, and/or
discharge summary is a symptom, the symptom is coded.
Ex: The only discharge diagnosis listed is "chest pain". The code
number 786.50 (chest pain, unspecified) is assigned.
2. When a symptom is listed that is unrelated to any of the diagnoses
listed, the symptom is coded.
Ex: The discharge diagnoses listed are acute myocardial infarction,
diabetes mellitus, and hepatomegaly. The hepatomegaly is also coded.
3. When a symptom is listed and is related to a listed discharge diagnosis
the symptom is not coded.
Ex: The discharge diagnoses listed are diabetes mellitus, acute
appendicitis, severe abdominal pain. Only the diabetes and the
appendicitis are coded. The abdominal pain is not coded.
Rules Governing Medical Codes for Procedures:
The same general rules apply to coding procedures as to coding diagnoses.
Medical procedures are coded by trained medical coders from the information
described on the health care facility abstract form or the discharge
summary/facesheet.
The principal procedure is the primary procedure most related to the principal
diagnosis and is performed for definitive treatment as opposed to diagnostic
and/or exploratory purposes.
Ex: Diagnosis = uterine fibroids.
Procedures = biopsy of uterus, total abdominal hysterectomy,
incidental appendectomy.
The hysterectomy is coded as the principal procedure and the
appendectomy and the biopsy are coded as secondary procedures.
All procedures documented on the discharge summary and/or facesheet are coded if
they fall into the following categories:
Biopsies (if related to the principal diagnosis and procedure or if
related to other listed diagnoses)
Surgical procedures
Cardiac catheterizations
D and C (following delivery or abortion only)
The following procedures are not coded:
Surgical approach
Operative cholangiogram
Lumbar puncture
CT scan
Endoscopy
Diagnostic D and C
Diagnostic radiology
Examination (under anesthesia, physical exam, etc.)
Manipulations
Physical therapy
Application or removal of casts, splints, etc.
Medical Coding Conventions:
Diagnostic codes--Up to ten diagnoses are coded for each hospital and nursing
home stay. The format for each diagnosis code is six positions. The following
conventions were used when entering diagnostic codes on the data tape:
1. ICD-9-CM diagnostic codes (including "V" codes) were entered beginning
with the second position of the variable field continuing through the
sixth position. There is an implied decimal point between the fourth
and fifth positions of the variable field.
2. If the diagnoses code required less than five digits the remaining tape
positions are blank.
3. Prefix codes "P" and "R" are coded in the first tape position. If the
diagnosis code has no prefix the first position is blank.
Ex. 1: _ 4 2 2 9 0 Code is 422.90
Ex. 2: _ V 7 1 1 _ Code is V71.1
Ex. 3: _ 4 3 6 _ _ Code is 436
Ex. 4: P 1 8 0 0 _ Code is P180.0
Ex. 5: R 1 7 4 9 _ Code is R174.9
4. E codes - External cause of injury codes
An external cause of injury code is provided, when applicable,
immediately after the medical diagnosis code which describes the nature
of the injury. E codes were entered on the data tape beginning in the
first position of the variable field and continuing through the fifth
position. There is an implied decimal point between the fourth and
fifth positions of the variable field. If an E code required less than
five positions the remaining positions are blank. If an E code is not
applicable (i.e. the medical diagnosis code is not a nature of injury
code) or could not be coded, the variable field is blank.
Ex. 1: E 9 0 6 1 Code is E906.1
Ex. 2: E 8 5 1 _ Code is E851
Procedure codes--Up to five procedures are coded for each health care facility
record. Each procedure code is formatted in a field containing four positions.
Procedure codes were entered beginning with the first position of the variable
field continuing through the fourth position. There is an implied decimal point
between the second and third positions of the variable field. If a procedure
code required less than four positions the remaining positions are blank.
Ex. 1: 4 2 9 2 Code is 42.92
Ex. 2: 0 3 1 _ Code is 03.1
SUBJECT INFORMATION
1-5 70 NHANES I Sample Sequence Number
6-7 Record Count
70 01-03 = Total number of records
Note: Each record on the file represents
an overnight stay in a health care facility
(hospital or nursing home). This variable
identifies for each subject the total
number of records on the file. It will be
the same for each record the subject has on
the file.
8-27 70 Blank
28 Survey Period Identifier
15 1 = NHEFS 1982-84
12 2 = NHEFS 1986
43 3 = NHEFS 1987
Note: This variable identifies the wave
where the record should have been
collected.
STAY IDENTIFIERS AND REPORTED INFORMATION
ON FACILITY STAYS
Note: The report section of the record
(positions 29-59 and 63-204) contains the
information on health care facility stays
that was reported on the questionnaire, on
a death certificate, on another
hospital/nursing home abstract form, or
obtained from other sources.
(29-33) Health Care Facility Stay ID Number
Note: When used in conjunction with the
sample sequence number this number uniquely
identifies each record on the tape. It is
composed of three variables: Supplemental
File Identifier, Facility Number and Stay
Number Within Facility. For example: a
Stay Number of S0102 refers to a facility
stay on the Supplemental file (S) in the
first facility reported for that subject
(01) and the second admission to that
facility (02).
29 Survey Period Identifier
70 S = Supplemental
Note: This variable identifies all
Supplemental records.
30-31 Facility Number
70 01-02 = Hospital/nursing home number
Note: For each NHEFS subject, a two digit
number was assigned to each facility in
which a stay occurred. Thus, if a subject
had multiple stays at the same facility,
all stays will have the same facility
number.
Facility numbers were assigned
consecutively. However, due to tape
editing, there are missing numbers in the
sequence of facility numbers.
32-33 Stay Number Within Facility
70 01-03 = Stay number
Note: The two digit stay numbers were
assigned to identify different stays in the
same facility.
Stay numbers within facilities were
assigned consecutively.
34-35 Facility ID Prefix
54 01 = Hospital
16 02 = Nursing Home
0 03 = Out of country, don't know, not
ascertained
Note: This variable identifies the type of
facility to which the request for a stay
record was mailed.
36-46 70 Blank
(47-52) Reported Admission Date
The date of admission to a facility is
reported by month, day and year.
47-48 Reported Month of Admission
28 01-12 = Month of admission
5 98 = Don't know
6 99 = Not ascertained
31 Blank = Record status code ASF (positions
60-62), or source code 3 (position
200) and record status code
(positions 60-62) not a cross-
referenced stay (CRM)
49-50 Reported Day of Admission
18 01-31 = Day of admission
15 98 = Don't know
6 99 = Not ascertained
31 Blank = Record status code ASF (positions
60-62), or source code 3 (position
200) and record status code
(positions 60-62) not a cross-
referenced stay (CRM)
51-52 Reported Year of Admission
38 81-87 = Year of admission (1981-1987)
1 98 = Don't know
0 99 = Not ascertained
31 Blank = Record status code ASF (positions
60-62), or source code (position
200) 3 and record status code
(positions 60-62) not a cross-
referenced stay (CRM)
53-54 70 Blank
(55-59) ID Number of Cross-Referenced Facility
Status Stay
Note: The ID number on the 1982-84, 1986
or 1987 NHEFS Facility Tape (positions 29-
33) is used to reference stays in a
hospital or nursing home that began during
the 1982-84, 1986 or 1987 NHEFS periods and
which continue into the survey period
identified in column 28. This variable is
coded only for records with a CRM in
positions 60-62.
55 Survey Period Identifier of Cross-
Referenced Facility Stay
0 1 = NHEFS 1982-84
0 2 = NHEFS 1986
0 3 = NHEFS 1987
5 S = NHEFS Supplemental HCFS file
65 Blank = Stay not cross-referenced
56-57 Facility Number of Cross-Referenced Stay
5 01 = Stay number
65 Blank = Stay not cross-referenced
58-59 Stay Number Within Facility of Cross-
Referenced Stay
5 01-02 = Stay number
65 Blank = Stay not cross-referenced
(60-62) RECORD STATUS
Note: The record status section of the
record (positions 60-62) contains
information on the outcome of the request
for a health care facility stay.
60-62 Record Status Code
Note: See Appendix A for an explanation of
the record status codes.
70 ASF - MAT = Record status code
(63-198) Reported Conditions and Codes
During the process of completing the
Hospital and Health Care Facility Chart
(HHCF) respondents described the conditions
that led to their overnight facility stays.
This information is included as a text
field on the stay record. Space is
allotted for the recording of up to four
reasons for the hospital or nursing home
stay (see positions 67-96, 101-130, 135-164
and 169-198).
A numeric code was assigned to each text
description to aid the researcher in the
use of this information (see positions 63-
66, 97-100, 131-134, 165-168). These
variables should be used in conjunction
with information in the abstract section,
i.e., ICD-9-CM diagnosis codes, present on
records with a record status code of MAT,
ASF or CRM. Appendix B contains a complete
description of these codes.
(63-96) First Reported Condition
63-66 Condition Code
39 01-37 = Condition Code (See Appendix B)
31 Blank = Source Code equal to 3 or Record
Status Code ASF.
67-96 Condition Text
39 Description of reason for facility stay
31 Blank = Source Code equal to 3 or Record
Status Code ASF.
(97-130) Second Reported Condition
97-100 Condition Code
10 01-37 = Condition Code (See Appendix B)
60 Blank = Source Code equal to 3 or Record
Status Code ASF or only one
condition reported.
101-130 Condition Text
10 Description of reason for facility stay
60 Blank = Source Code equal to 3 or Record
Status Code ASF or only one
condition reported.
(131-164) Third Reported Condition
131-134 Condition Code
1 01-37 = Condition Code (See Appendix B)
69 Blank = Source Code equal to 3 or Record
Status Code ASF or less than three
conditions reported.
135-164 Condition Text
1 Description of reason for facility stay
69 Blank = Source Code equal to 3 or Record
Status Code ASF or less than three
conditions reported.
(165-198) Fourth Reported Condition
165-168 Condition Code
0 01-37 = Condition Code (See Appendix B)
70 Blank = Source Code equal to 3 or Record
Status Code ASF or less than four
conditions reported.
169-198 Condition Text
0 Description of reason for facility stay
70 Blank = Source Code equal to 3 or Record
Status Code ASF or less than four
conditions reported.
199 70 Blank
200 Source of Report of Stay that Initiated
Request for Abstract
31 3 = Information from other source
39 4 = Information from prior NHEFS interview
201-204 70 Blank
(205-379) ABSTRACT DATA
Note: The abstract data portion of the
record (positions 205-379) contains
information obtained from an abstract form
returned by the facility. This section of
the stay record (excluding positions 207-
208) will be blank when a facility did not
return an abstract form for a stay.
205-206 Abstract Number
70 01-03 = Number of abstract
Note: For each subject, a two digit number
was assigned consecutively to each abstract
form received.
207-208 Total Number of Abstracts Received
70 01-03 = Total number of abstracts received
Note: This number represents the total
number of abstracts received for each
subject. The total number is repeated on
each subject record.
209 Facility Record Type
54 1 = Hospital
16 2 = Nursing home
(210-215) Date of Admission
210-211 Month of Admission
70 01-12 = Month of admission
212-213 Day of Admission
70 01-31 = Day of admission
214-215 Year of Admission
70 72-87 = Year of admission (1972-1987)
(216-221) Date of Discharge
216-217 Month of Discharge
55 01-12 = Month of discharge
15 97 = Inapplicable (still at facility on
date of last interview)
0 99 = Not ascertained
218-219 Day of Discharge
55 01-31 = Day of discharge
15 97 = Inapplicable (still at facility on
date of last interview)
0 99 = Not ascertained
220-221 Year of Discharge
55 72-87 = Year of discharge (1972-1987)
15 97 = Inapplicable (still at facility on
date of last interview)
0 99 = Not ascertained
222-225 Length of Facility Stay
55 0001-0106 = Total number of days in
facility
15 9997 = Inapplicable (still at
facility on date of last
interview)
0 9999 = Not ascertained
Note: Length of stay is calculated by
subtracting the date of admission from the
date of discharge. For subjects with
nursing home stays, brief breaks were
collapsed into one continuous nursing home
stay (see positions 216-221).
226 Was the Patient in Cardiac Intensive Care
Unit?
5 1 = Yes
30 2 = No
16 7 = Inapplicable (facility is a nursing
home)
19 9 = Not ascertained
227-229 Number of Days in Cardiac Intensive Care
Unit
5 001-009 = Number of days
65 997 = Inapplicable (position 226 =
2,7,9)
0 999 = Not ascertained
230 Was the Patient In Other Intensive Care
Unit?
0 1 = Yes
35 2 = No
16 7 = Inapplicable (facility is a nursing
home)
19 9 = Not ascertained
231-233 Number of Days in Other Intensive Care Unit
70 997 = Inapplicable (Position 230 = 2,7,9)
234 Patient Admitted to Nursing Home From:
5 1 = Private residence
9 2 = Acute care hospital
0 3 = Chronic disease hospital
1 4 = Other nursing home
54 7 = Inapplicable (facility is a hospital)
1 9 = Not ascertained
235 Disposition of Hospital Patient
36 1 = Routine discharge/discharged home
0 2 = Left against medical advice
2 3 = Discharged/transferred to another
facility or organization
2 4 = Discharged/referred to organized
home care service
1 5 = Died
1 6 = Not discharged/still in hospital on
the date of last interview
16 7 = Inapplicable (facility is a nursing
home)
12 9 = Subject discharged, disposition not
ascertained
236 Disposition of Nursing Home Patient
14 1 = Not discharged/still in a nursing
home on date of last interview
1 2 = Discharged to private
residence/referral to organized
home care services
0 3 = Died
0 4 = Discharged to private residence/no
referral
1 5 = Transferred to another facility
54 7 = Inapplicable (facility is a
hospital)
0 9 = Subject discharged, disposition not
ascertained
237 Transferred to Another Health Care Facility
0 1 = Acute care hospital
0 2 = Other nursing home
1 3 = Chronic disease hospital
0 4 = Other
69 7 = Inapplicable (Position 236 =
1,2,3,4,7 or 9)
0 9 = Not ascertained
238-239 Number of Diagnoses
67 01-10 = Number of diagnoses
3 99 = Not ascertained
Note: This variable identifies the total
number of diagnoses entered on the
abstract. The number of coded diagnoses
may exceed the maximum number allowed on
the data tape (10).
240-245 Principal Diagnosis
67 ICD-9-CM Code
3 999999 = Not ascertained
Note: See medical coding specifications.
246-250 Principal Diagnosis E Code
10 ICD-9-CM Code
60 Blank = Principal diagnosis does not
require E code
Note: See medical coding specifications.
251-256 Second Diagnosis
52 ICD-9-CM Code
18 999997 = Inapplicable (only one
diagnosis coded)
Note: See medical coding specifications.
257-261 Second Diagnosis E Code
3 ICD-9-CM Code
18 99997 = Inapplicable (only one
diagnosis coded)
49 Blank = Second diagnosis does not
require E code
Note: See medical coding specifications.
262-267 Third Diagnosis
40 ICD-9-CM Code
30 999997 = Inapplicable (less than three
diagnoses coded)
Note: See medical coding specifications.
268-272 Third Diagnosis E Code
2 ICD-9-CM Code
30 99997 = Inapplicable (less than three
diagnoses coded)
38 Blank = Third diagnosis does not
require E code
Note: See medical coding specifications.
273-278 Fourth Diagnosis
30 ICD-9-CM Code
40 999997 = Inapplicable (less than four
diagnoses coded)
Note: See medical coding specifications.
279-283 Fourth Diagnosis E Code
0 ICD-9-CM Code
40 99997 = Inapplicable (less than four
diagnoses coded)
30 Blank = Fourth diagnosis does not
require E code
Note: See medical coding specifications.
284-289 Fifth Diagnosis
16 ICD-9-CM Code
54 999997 = Inapplicable (less than five
diagnoses coded)
Note: See medical coding specifications.
290-294 Fifth Diagnosis E Code
1 ICD-9-CM Code
54 99997 = Inapplicable (less than five
diagnoses coded)
15 Blank = Fifth diagnosis does not
require E code
Note: See medical coding specifications.
295-300 Sixth Diagnosis
8 ICD-9-CM Code
62 999997 = Inapplicable (less than six
diagnoses coded)
Note: See medical coding specifications.
301-305 Sixth Diagnosis E Code
0 ICD-9-CM Code
62 99997 = Inapplicable (less than six
diagnoses coded)
8 Blank = Sixth diagnosis does not
require E code
Note: See medical coding specifications.
306-311 Seventh Diagnosis
4 ICD-9-CM Code
66 999997 = Inapplicable (less than seven
diagnoses coded)
Note: See medical coding specifications.
312-316 Seventh Diagnosis E Code
0 ICD-9-CM Code
66 99997 = Inapplicable (less than seven
diagnoses coded)
4 Blank = Seventh diagnosis does not
require E code
Note: See medical coding specifications.
317-322 Eighth Diagnosis
2 ICD-9-CM Code
68 999997 = Inapplicable (less than eight
diagnoses coded)
Note: See medical coding specifications.
323-327 Eighth Diagnosis E Code
0 ICD-9-CM Code
68 99997 = Inapplicable (less than eight
diagnoses coded)
2 Blank = Eighth diagnosis does not
require E code
Note: See medical coding specifications.
328-333 Ninth Diagnosis
2 ICD-9-CM Code
68 999997 = Inapplicable (less than nine
diagnoses coded)
Note: See medical coding specifications.
334-338 Ninth Diagnosis E Code
0 ICD-9-CM Code
68 99997 = Inapplicable (less than nine
diagnoses coded)
2 Blank = Ninth diagnosis does not
require E code
Note: See medical coding specifications
339-344 Tenth Diagnosis
2 ICD-9-CM Code
68 999997 = Inapplicable (less than ten
diagnoses coded)
Note: See medical coding specifications.
345-349 Tenth Diagnosis E Code
0 ICD-9-CM Code
68 99997 = Inapplicable (less than ten
diagnoses coded)
2 Blank = Tenth diagnosis does not
require E code
Note: See medical coding specifications.
350-351 Number of Procedures
54 00-05 = Number of procedures
16 97 = Inapplicable (facility is a nursing
home)
Note: This variable identifies the total
number of procedures coded on the facility
abstract. The number of reported
procedures from a hospital may exceed the
maximum number of five coded on this data
tape.
352-355 First Procedure
21 ICD-9-CM Code
49 9997 = Inapplicable (facility is a
nursing home or no procedures
coded)
Note: See medical coding specifications.
356-359 Second Procedure
6 ICD-9-CM Code
64 9997 = Inapplicable (facility is a
nursing home or only one
procedure coded)
Note: See medical coding specifications.
360-363 Third Procedure
3 ICD-9-CM Code
67 9997 = Inapplicable (facility is a
nursing home or less than
three procedures coded)
Note: See medical coding specifications.
364-367 Fourth Procedure
2 ICD-9-CM Code
68 9997 = Inapplicable (facility is a
nursing home or less than four
procedures coded)
Note: See medical coding specifications.
368-371 Fifth Procedure
1 ICD-9-CM Code
69 9997 = Inapplicable (facility is a
nursing home or less than five
procedures coded)
Note: See medical coding specifications.
372 Pathology Report
3 1 = Required and present
0 2 = Required and not present
51 6 = Not required
16 7 = Inapplicable (facility is a nursing
home)
373-429 70 Blank
Figure 1
Supplemental HCFS record layout
- Facility
identifers
- Reported date of
admission
- Reported cause of
admission
- Source of report
MAT, CRM or ASF
- Actual dates
admission and
discharge
- ICD-9-CM
diagnoses
- Discharge status
from hospitals and
nursing homes
Record
Report Section Status Section Abstract Section
Figure 2
Examples of matching process and record status codes
Record status code
Match
Report Section
MAT or CRM
Abstract Section
Additional abstract found
No Report section
ASF
Abstract Section
APPENDIX A
RECORD STATUS CODES
Code Frequency Description
ASF - 31 "Additional Stay Found." This code was assigned when
a returned in-scope abstract could not be matched to
a reported stay.
CRM - 5 "Cross-Referenced Match." This code indicates a stay
that was begun prior to a NHEFS survey period and
continues into a later survey period. For this type
of stay, the abstract is brought forward from the
previous wave. The discharge date and discharge
status information are the only positions that are
updated. The admission date is prior to the most
recent interview because this is a continuing stay.
Thus, it appears to be, but is not, out-of-scope for
the wave specified in position 28.
MAT - 34 "Record Match." This code was assigned when a
received abstract matched a reported stay. This code
was assigned to in-scope reports.
APPENDIX B
NUMERIC CODES FOR REPORTED CONDITIONS ON
HEALTH CARE FACILITY STAY RECORDS
Code for reported Condition
Condition Description
01 Arthritis
02 Gout
03 Heart attack
04 Another heart condition besides heart attack
05 Coronary bypass surgery
06 Pacemaker repair, insertion and/or replacement
07 Not assigned in 1987 or 1992 files, see notes below
08 Stroke or CVA (cerebrovascular accident)
09 Diabetes
10 High blood pressure
11 Cancer and/or cancer treatment other than skin cancer
1101 Malignant melanoma
1102 Skin cancer other than malignant melanoma
12 Fractured hip
13 Another type of bone fracture besides a hip fracture
14 Not assigned in 1987 or 1992 files, see notes below
15 Surgery
16 Don't know
17 Not ascertained
18 Tests/observation/x-rays/physical exam
19 Digestive/endocrine condition
20 Respiratory condition (including influenza and
pneumonia)
21 Infection
22 Kidney/bladder/urinary condition
23 Debility/pain
24 Male reproductive condition
25 Musculoskeletal problem or injury other than a
fracture
2502 Back pain (1982-84 only)
26 Circulatory condition
27 Female reproductive condition
28 Mental illness
29 Neurologic condition
30 Nutritional condition or dehydration
31 Bleeding or blood disorder
32 Skin condition
33 Condition not elsewhere coded
34 Admission to a facility other than an acute care
hospital
35 In a facility at time of death
36 Cataracts
3603 Eye problem other than cataracts, detached retina or
glaucoma
37 A fall
Guidelines for Use of Numeric Codes for Reported Conditions
Background
During the process of completing the Hospital and Health Care Facility
(HHCF) chart respondents were asked to describe the conditions that led to
their facility stays and this information is included as a text field on
the stay record. The text portion of the reported condition contains
standard nomenclature for certain conditions (see Type A conditions below)
or the respondent's own words. If necessary the respondent's descriptions
was edited to fit into the 30 positions available in the record. A
numeric code was also assigned to each description. This was done so that
users would not have to deal with alphabetic description fields when
investigating reasons for facility stays. Space is allotted on the report
section of the facility stay record for recording of up to four reasons
for the hospitalization or nursing home stay (positions 63-198 of the HCFS
record).
Note that codes "07" and "14" are not included in the coding structure for
the 1987 and 1992 files. These codes had been assigned to conditions in
the 1982-84 and 1986 followups. The 1987 and 1992 followup questionnaires
differ from the earlier versions and sufficient information was not
collected to assign these codes.
Reported conditions and their associated codes can be divided into six
types depending on where in the interview the stay was reported and the
amount of information obtained: specific conditions included in
interview questions (Type A); conditions which are well-defined but for
which no question exists in the interview (Type B); unknown conditions
(Type C); conditions about which there is no specific interview question
but for which sufficient information is available to attribute them to
disorders of a major body system (Type D); conditions that are broadly
defined and/or cannot be attributed to a single major body system (Type
E); and conditions that cannot be classified into any of the above
categories (Type F). Each condition type, the associated codes and the
rules for assigning the reported conditions to the categories of the
coding structure are described in detail below.
Type A - Conditions about which the respondent was asked in the interview.
For example, if a respondent answered "yes" to 1992 interview question B-
17 ("Were you hospitalized for your arthritis?"), then a condition code of
"01" and a text field containing "arthritis" would be included on the
facility stay record. Type A conditions are:
01 Arthritis (B-17)
02 Gout (B-17)
03 Heart attack (B-23)
04 Other heart conditions (B-24)
05 Coronary bypass surgery (B-27)
06 Procedures for pacemakers (B-29)
08 Stroke (B-35)
09 Diabetes (B-42)
10 High blood pressure (B-52)
11 Cancer (B-66) other than skin cancer
1101 Malignant Melanoma (B-60)
1102 Skin cancer (B-63) other than
malignant melanoma
12 Fractured hip (B-80)
15 Surgery (B-63) (1986 only)
20 Pneumonia, bronchitis and influenza (B-90)
Note: this code is also found under Type D
because other respiratory conditions are also
coded to category 20
22 Kidney, bladder or urinary problem (B-97)
2502 Back pain (E-46) (1982-84 only)
34 Care in non-acute care facility (B-121)
35 In a facility at death (B-127)
36 Cataracts (B-108)
37 A fall (B-89)
Complete agreement between responses to the questions in interviews and
Type A condition codes on the facility stay file should not be expected.
There are several reasons for a lack of agreement between these two data
sources.
First, the respondent may report a facility stay for a given condition in
the interview and yet no facility stay record containing the condition may
appear on the HCFS file. This would result if: (1) it was determined that
the hospitalization did not last overnight causing the stay to be deleted
from the HCFS file; or (2) the reported stay was found to be "out-of-
scope". (See the introduction to this codebook and the Plan and Operation
for definitions of out-of-scope stays.)
Second, data may be inconsistent between the interview and the HCFS file
if the respondent remembered and reported a condition after responding to
the corresponding question in the interview. This tended to occur at the
time the interviewer was recording information on the HHCF chart. For
example, while recording information on a stay for high blood pressure,
the respondent may add that he/she was also hospitalized at that time for
a heart condition. The respondent may not have reported the
hospitalization when asked about heart conditions in the interview and the
interview information may not have been updated to reflect this additional
condition. However, heart condition would appear on the HCFS file.
Type B - Conditions which do not have a corresponding question in the
interview but for which sufficient descriptive information is available to
allow them to be easily coded:
13 Bone fracture
18 Tests and observation
Type C - Unknown conditions:
16 Don't know
17 Not ascertained
Type D - Conditions for which there is not a specific question in the
interview but which can be attributed to disorders of a major body system:
19 The digestive/endocrine system
20 The respiratory system
Note: this code is also found under Type A
because the specific question about pneumonia,
bronchitis and influenza (B-90) is coded to the
general category
24 The male reproductive system
25 The musculoskeletal system
26 The circulatory system (except strokes)
27 The female reproductive system
29 Neurologic disorders
31 Blood disorder/bleeding
32 Skin problem
3603 Eye problem (except cataracts, detached retina
or glaucoma)
Type E - Conditions which are broadly defined or are attributed to
problems of more than one major body system:
15 Surgery
21 Infections
23 Debility and pain
28 Mental illness
30 Nutrition and dehydration
Type F - All conditions that cannot be assigned to one of the above codes:
33 Other conditions
Additional information on reasons for a facility stay is available in the
abstract section of the record (positions 205-379) if an abstract has been
matched to the report. In general information from the abstract is
considered a more accurate determination of the conditions associated with
the stay than are the reported conditions. The condition codes in the
report section of stay records do provide useful information in the
absence of a medical abstract. Both flexibility and caution should be
exercised when selecting stays based on these codes. In order to help the
analyst use these condition codes effectively, a description of the code
assignment procedure along with an example is provided.
Rules for Assignment
The numeric codes were assigned to the respondent's non-technical
descriptions by trained medical coders. In order to minimize variation
among the coders assigning these codes, precedence rules were defined.
Generally, a condition was coded to the most specific category in which it
could be placed. The assignment rules are described below in priority
order, e.g. Rule 2 was used only if Rule 1 did not apply and so forth.
Rule 1: If a condition was one about which there was a
specific question in the interview, the code appro-
priate for that question was assigned. (Type A
conditions)
Rule 2: If the textual description could be coded to a
narrowly defined condition not specifically asked or
to the unknown category, the appropriate Type B or
Type C code was assigned.
Rule 3: Conditions that could not be coded to a specific
question but could be coded to a major body system
were assigned the appropriate Type D code.
Rule 4: General descriptions, symptoms and conditions not
coded by rules 1 through 3 were coded at the
discretion of the medical coder, again with emphasis
on as much specificity as possible. For example,
"HEADACHES, BRAIN TUMOR" would be coded to "29 -
Neurologic disorders", not to "23 - Debility and
pain". (Type D or Type E conditions)
Rule 5: Everything that could not be assigned a code after
applying the above rules was coded to "33 - Other
conditions". (Type F conditions)
Considerations for the data user
The condition codes in the report section should be used in conjunction
with the information in the abstract section. Returned abstracts were
matched to reports if one of the reported conditions matched one of the
discharge diagnoses on the abstract. Other conditions reported for the
same stay may or may not be confirmed in the matched medical abstract. If
the condition of interest is not indicated as a discharge diagnosis on the
medical record, the analyst may not want to accept the reported condition
as a reason for the stay. Similarly, conditions may be listed as
discharge diagnoses that do not appear on the report section. See the
introduction to this codebook for a description of the match criteria.
