Procedures
Investigators used a quasi-experimental, pretest–posttest
comparison group design, with random assignment of work
group to intervention group. The primary independent variable
was the ergonomic intervention, with three levels. The
primary dependent variable was the workers’ positioning and
workstation design. After identifying the eligible participants,
researchers assigned participants to one of three groups
depending on their designated “cell” (the work area to which
specifically assigned employees report each day). In other
words, researchers randomly assigned one of the three
research conditions to each cell.