Setting and Subjects
The study site for this program was an automotive factory
in the Midwest. All workers included in the plant’s longstanding
Hearing Conservation Program were invited to
participate. Following their annual audiometric test, workers
(N = 2831) participated in pretest data collection over
a 32-month period. Posttest data were obtained when
workers returned to the plant’s medical clinic for their next
annual audiometric test. Only those workers whose annual
exam occurred between 6 and 18 months following the
pretest were included.
Complete pretest and posttest data were available for
less than one-half of the workers (n = 1325). There were
no significant differences in gender, ethnicity, type of HPDs
used, or perceived hearing ability between those who
returned for the posttest and those who did not. A significantly
larger proportion of those with bachelor’s degrees
failed to return for the posttest. This is presumed to be due
to workers in professional positions who were not required
Nursing Research September/October 2003 Vol 52, No 5 Intervention to Increase Use of Hearing Protection 291
to be part of the plant’s Hearing Conservation Program,
but participated in the pretest out of curiosity. There was
also a slight, albeit significant, difference in noise exposure
with lower levels for the pretest-only group as compared to
those who provided both pretest and posttest data (90.2
dB vs. 90.7dB, respectively). The professionals who were
likely to have lower noise exposures may have contributed
to this result. In addition, the group that did not participate
in the posttest contained significantly more older
workers and workers who had more years of service at the
plant. This would be expected because most workers who
were no longer employed at the plant had most likely
retired.
Reasons for incomplete data included:
• audiometric test and return visit training 6 months
or 18 months since pretest (n = 389)
• data recorded for only one intervention and corresponding
audiogram for workers who were presumed
to have left employment at the plant before
posttest data collection had been completed (n =
335)
• pretest data collected during the last 5 months of the
study, which did not allow sufficient time to return
for posttest within the minimum 6-month time frame
(n = 223)
• unknown reasons for no return visit (n = 559)