The Common BLSA Data Set

5.2.2 Non-Longitudinal Data, BLS$CDS$NL$DAT
This data file contains items which are not specific to one participant-visit. Except for 'Status' and 'Autopsy status', variables are constant over time. The record format is fixed-length (48 characters per record) and location refers to column numbers within the file.

data item                                 variable       location  source
identification number                     idno    1-4        
Date of birth                             dob     6-15   0-1-1
Race                                      racecd  17     vital
                                                         stats
Current status (A, D, W, or F)            stat    19     computed
Date of death                             dod     21-30  999-1-1
BLSA physician consensus as to cause of death     bpcat  32-33     999-1-21
Immediate cause of death                  imcao   35-36  999-1-23
Underlying cause of death                 ucoda   38-42  999-1-39
Autopsy status (1=member of autopsy study)        autstat          44   computed
Follow-up status (1=follow-up data on file)       fdstat 46        computed
Minority population tracking group        poptrak 48        computed

5.2.3 Medications Data, BLS$CDS$RX$DAT
The record format is fixed-length (82 characters per record) and location refers to column numbers within the file. Card or record numbers can be 1 to 99.
Information types 001 and 901 indicate that data are from the pre-1979 era that were collected within the Medical History. Information type 012 are data which were collected independently as text between 1979 and 1990. The most complete data are represented by information type 812 which began to be collected in 1990.

data item                                 variable       location  source
identification number                     idno    1-4        
visit                                     visit   6-7    
Drug name                                 drug    9-37   812-*-1
Drug code                                 druco   39-42  812-*-31
Amount of medication per tablet or other unit     aompt  43-47     812-*-35
Units for the amount of medication        uftao   48     812-*-40
Tablets or other units per dose           tooup   49-50  812-*-41
Doses per week                            dopew   51     812-*-43
Doses per day                             doped   52     812-*-44
How is medication taken                   hoism   53     812-*-45
Use                                       use     54     812-*46
length of use                             leofu   55     812-*-47
If stopped, how long ago                  ishla   56     812-*-48
If stopped, reason for stopping           isrfs   57     812-*-49
ICD-9-CM                                  icd9a   58-63  812-*-50
ICD-9-CM                                  icd9b   64-69  812-*-56
ICD-9-CM                                  icd9c   70-75  812-*-62
Taken within the past 48 hours            twtpq   76     812-*-68
Information type                          info    77-79  
Card number                               card    80-81  
Verified                                  verified       82

5.2.4 Diagnosis Data, BLS$CDS$DX$DAT
In the masterfile, diagnosis data are repeated at each visit, with updates added to reflect activity since the last visit. However, the method of recording in the masterfile carries forward data from the prior visit. Since information regarding beginning and ending periods for each diagnosis are recorded, the most comprehensive, correct, and usable list of diagnoses is the one affiliated with the most recent visit. For that reason, only this last set of data is present in the file. If a researcher requires a retrospective look at the data from a prior visit, those data are still available from the masterfile.
The format is fixed-length records and locations are given as column numbers in the file. The source for all of this data is information type 3, which is repeated in the masterfile as many times as necessary to accommodate all of the data, two diagnoses per repetition. The source shown below is that of the first repetition on the first card.

data item                                 variable       location  source
identification number                     idno    1-4        
visit                                     visit   5-6
ICD-9-CM diagnosis code #1                dxicd1  7-12   3-1-1
ICD-9-CM diagnosis code #2                dxicd2  13-18  3-1-7
ICD-9-CM diagnosis code #3                dxicd3  19-24  3-1-13
source of diagnosis                       soofd   25     3-1-19
category (active, inactive, signs, irrelevant)    caisi  26        3-1-20
certainty of diagnosis                    ceofd   27     3-1-21
year (19xx) diagnosis last active         yedil   28-29  3-1-22
year (19xx) diagnosis first active        yedif   30-31  3-1-26
diagnosis text                            dxtext  32-87  text masterfle

5.2.5 Hospitalization and Illness Data, BLS$CDS$HI$DAT
These data are not longitudinal in nature, but rather reported by the date of incidence. The file contains both types of data, intermixed and tagged with the type of information that it represents; 1 for hospitalizations, and 2 or 3 for illnesses (2 for current or past illness, and 3 for illnesses about which the participants are uncertain as to their history). Only positive responses in the masterfile are reflected in this dataset.
The format is variable length records, with the specific data items being dependent upon the type tag. The location is the relative field position within the file. The source is the BLSA NONLONG (non-longitudinal) file, and the source shown is the subfile name and field number.

data item                                 variable       location  source
type of information                       hori    2      generated
identification number                     idno    1        

** for hospitalization records (hori = 1)
date(s) of hospitalization (text)         datehosp       3         HOSP-1
reason for hospitalization                reashosp       4         HOSP-2
ICD-9-CM diagnosis code #1                hosicd1 5      HOSP-3
ICD-9-CM diagnosis code #2                hosicd2 6      HOSP-4
ICD-9-CM diagnosis code #3                hosicd3 7      HOSP-5

** for major illness records (hori = 2 or 3)
year of onset of illness                  yearill 3      PHH-3
illness code                              illcode 4      PHH-1
treatment code #1                         illtrt1 5      PHH-4
treatment code #2                         illtrt2 6      PHH-5
treatment code #3                         illtrt3 7      PHH-6

5.2.6 Procedure Data, BLS$CDS$PRC$DAT
These data also are not longitudinal in nature, but rather reported along with the date(s) of occurrence. The file contains both surgical and test procedure data, intermixed and tagged with the type of information that it represents; 1 for surgical procedures and 2 for test procedures. Only positive responses in the masterfile are reflected in this dataset.
The format is variable length records. The location is the relative field position within the file. The source is the BLSA NONLONG (non-longitudinal) file, and the source shown is the subfile name (PSP for surgical and PTP for test procedures) and field number.

data item                                 variable       location  source
identification number                     idno    1       
type of information                       proctyp 2      generated
name of procedure                         procname       3         PSP/PTP-1
year first performed                      procyr1 4      PSP/PTP-2
year second performed                     procyr2 5      PSP/PTP-3
year third performed                      procyr3 6      PSP/PTP-4

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