Identification of Vietnam Era Veteran Twins
Numerous possible twin finding strategies were analyzed
(Eisen et al., 1987) and it was ultimately decided that the best approach
was to use computerized records maintained by the Department of Defense
(DoD), supplemented with VA computer files. It was during the Vietnam
era that the DoD began to computerize their record keeping and not all
discharged veterans were contained within the files; each branch of
service (Army, Navy and Marines, Air Force, Coast Guard) transitioned
from the old pencil and paper systems to computerization at different
times during the era. The DoD estimated that roughly 5.5 out of the
9 million Vietnam era veterans were included in their systems. With
help from the DoD, a computerized record linkage methodology was developed
that identified pairs of records that had a reasonable probability of
being twins. The algorithm that was used involved the following criteria:
males, born between 1939-1957, served on active duty during the Vietnam
era (the interval 1965-1975), same last name, different first name,
same date of birth, and same first 5 digits of the Social Security Number
(Goldberg et al., 1993). In total 15,711 potential Vietnam era veteran
twin pairs were identified using the matching algorithm.
All military records of discharged veterans are maintained at the
National Personnel Records Center (NPRC) in St. Louis. The records
of veterans from the Vietnam era are all stored in hard-copy format
and take up approximately seven shelf-miles of space. There is no
central computer file at NPRC aside from a crude index that serves
as a pointer to the hardcopy storage location for the record of a
particular veteran. The hard-copy military record for each of the
potential twin pairs was retrieved. Within the hard-copy record for
each veteran is their place of birth and the full names of both parents.
Twinship was confirmed when there was an exact match on place of birth
and parental names. In total, 7,369 twins were confirmed from the
initial pool of potential twins identified from the record matching.
These twins form the core of the VET Registry.
|
