Personal intercept interviews are conducted among a total of 1,200 college students enrolled in four year colleges and universities throughout the United States. All interviews were conducted by professional interviewers via on campus, one-on-one random intercepts.

Respondents are qualified as undergraduate, full-time students. Quotas are established to insure equal numbers of males and females within each year of study. The actual number of interviews completed is illustrated in the first chart on the right.

Interview quotas are established to insure adequate representation, consistent with the four Census Bureau regions and nine divisions based on school location (North, South, Midwest and West), type of school (Public or Private), and enrollment size. The number of completed interviews for each of the resulting proportionally representative 56 cells is illustrated in the second chart on the right.