The study was conducted at two New Jersey
locations of a petrochemical research and develop-
ment facility. In 1994, 373 employees responded
``yes'' to a site wide e-mail survey asking whether
they used a VDT for two or more hours a day.
Employees meeting the above criteria were
assumed to be at risk of developing VDT-related
musculoskeletal injuries; these employees were
encouraged to attend a VDT training program
and to complete a self-administered questionnaire
prior to attendance. A total of 292 employees
(79%) completed the baseline self-administered
questionnaire and attended training.
Approximately one year later, the 292 emp-
loyees who had completed the baseline question-
naire and training were asked to complete the
same questionnaire again. A total of 170 of the
original 292 employees (58%) completed both
questionnaires.
For a variety of reasons, the company did not
want to exclude any eligible VDT workers from
the training program. As a result, we could not
randomly select a group of VDT users to not
receive the training (i.e., a control group). Hence,
we utilized a one-group pretest±posttest design, a
design frequently used in non-experimental
research (Cook and Campbell, 1979).
2.2. The VDT training program
The training program was taught by ergono-
mists and ergonomics-trained industrial hygienists.
To ensure that the training was delivered in a
standardized manner to all employees, the same
ergonomists and industrial hygienists taught all
sessions. In addition, handouts containing the
course outline and material were distributed at the
start of each session to ensure a consistent delivery
of information.
The training covered correct workstat