To collect empirical data for valid, unbiased hypothesis testing, an
interview template was created that included a set of demographic,
project performance, and open-ended questions. All interviews
were conducted in person or over the phone. The following demographic
data were obtained from each project: location, scope (in
U.S. dollars), percent complete, worker-hours accumulated, delivery
method, contract method, project type, and whether the project
is union or open shop labor. Additionally, project performance data
were requested, including the number of first-aid injuries, number
of OSHA recordable injuries, number of defects, cost of rework,
and number of worker-hours spent on rework.