Ronald F CzajaRonald Czaja, associate professor (retired) of sociology and anthropology at North Carolina State University, taught courses in both undergraduate and graduate research methodology and medical sociology. His methodological research iterests focus on sampling rare populations, response effects in surveys, and the cognitive aspects of questionnaire design. From 1969 to 1990 he was at the Survey Research Laboratory, University of Illinois at Chicago, as project coordinator, co-head of sampling, assistant director, and principal investigator. Read More Read Less