The use of ergonomic measures was described at the population
level by means of the percentage of workers in each category using
ergonomic measures and the change in percentage from baseline to
follow-up. A change in the use of ergonomic measures at the individual
level was described by the percentage of respondents who
reported a decrease, an increase, or no change in using or not using
ergonomic measures. Statistical significance of the change from
baseline to follow-up 2 years later was tested by the Wilcoxon
signed-rank test for paired data.
The frequency and duration of MSDs were dichotomized into
“MSD present” (regular and sustained) and “no MSD” (never and
sometimes). The prevalence of MSDs was described at the population
level by means of the percentage of workers reporting MSDs for
each bodily region and the change in percentage from baseline to
follow-up. A change in MSDs at the individual level was described by
the percentage of respondents who reported a decrease, an increase,
or no change in MSDs. Statistical significance of the change from
baseline to follow-up 2 years later was tested by the McNemar test
for paired data. The work relatedness was described by the percentage
of respondents for each answer category