Age and Decimal Date

There is no need for these data to updated periodically.

There is generally one observation for each participant in this follow-up project.

Data were collected in 1991 and 1992 by Dr. Lauren Whetstone.

The variable VISIT is, in fact, follow-up number. For this project, all should be either "1" or "2."

AGE at visit is calculated to the nearest tenth of a year.

DECDT is the year of visit calculated to the nearest tenth of a year. It can be interpreted as follows:

	.0 = January 1 - February 7
	.1 = February 8 - March 15
	.2 = March 16 - April 21
	.3 = April 22 - May 27
	.4 = May 28 - July 3
	.5 = July 4 - August 8
	.6 = August 9 - September 14
	.7 = September 15 - October 20
	.8 = October 21 - November 26
	.9 = November 27 - December 31

There is no comparable information type in the traditional BLSA Master File. These data are comparable, however, to infoad.* and in1fdad.*.

                                          The SAS System        09:22 Friday, October 30, 1998
                                        CONTENTS PROCEDURE
         Data Set Name: LIBRARY.IN2FDAD                        Observations:         464
         Member Type:   DATA                                   Variables:            4
         Engine:        REMOTE                                 Indexes:              0
         Created:       14:35 Wednesday, May 13, 1998          Observation Length:   32
         Last Modified: 14:35 Wednesday, May 13, 1998          Deleted Observations: 0
         Protection:                                           Compressed:           NO
         Data Set Type:                                        Sorted:               NO
         Label:
                           -----Engine/Host Dependent Information-----
            Data Set Page Size:       8192
            Number of Data Set Pages: 2
            File Format:              607
            First Data Page:          1
            Max Obs per Page:         254
            Obs in First Data Page:   229
            Filename:                 DISK$BETA14:[BLS$CDS.BLS$F2DF]IN2FDAD.SASEB$DATA
            Host Format:              AXP
            Disk Blocks Allocated:    36
                      -----Alphabetic List of Variables and Attributes-----
          #    Variable    Type    Len    Pos    Label
          
          3    AGE         Num       8     16    Age at Follow-up
          4    DECDT       Num       8     24    Year of Follow-up to the Nearest Tenth
          1    IDNO        Num       8      0
          2    VISIT       Num       8      8