One needs to have acquired first-rate methodological tools pertinent to survey research, including interview skills and design of questions, quantitative techniques of analysis, qualitative research (an essential precursor to good survey-based research), and to have some more than nodding familiarity with the variety of disciplines that work on sexual topics.  Sex research is highly interdisciplinary and requires a good footing in biology, psychology, sociology, and anthropology. - Edward Laumann, Full Professor, Sociology, University of Chicago