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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.  

     



This page last reviewed: Thursday, January 28, 2016
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