|
Each year since the inception of the study the NAWS has interviewed
approximately 2,500 randomly selected agricultural workers across the United
States. The sampling procedure respects seasonal and regional fluctuations in
the level of agricultural work activity. Each fiscal year includes a fall
cycle, a winter cycle, and a spring/summer cycle of interviews. The number of
interviews conducted during a cycle is proportionate to the amount of
agricultural activity at that time of year.
The NAWS uses sites' area sampling to obtain a nationally representative
group of workers while containing travel costs of survey staff. A sample of 288
counties in 25 states was selected to represent 12 distinct agricultural
regions. No fewer than four counties were chosen from each region. Multi-stage
sampling is used to choose respondents in each cycle. The likelihood of a given
site being selected varies with the size of its agricultural payroll.
Agricultural employers within each of the selected counties are chosen
randomly from public agency records, including unemployment insurance files and
Agricultural Commissioners' pesticide registrations. These sources of employer
names are supplemented from lists maintained by such agencies as the Bureau of
Labor Statistics, the Agricultural Soil and Conservation Service, and the state
Department of Industrial Relations.
NAWS lead interviewers' contact the selected employers, explain the purpose
of the survey, and obtain access to the work site to schedule interviews.
Interviewers then go to the work site, explain the purpose of the survey to the
workers, and ask a random sample of them to participate. Interviews then are
conducted in the worker's home or at another location of the worker's choice.
| 
