The national YRBS uses a three-stage cluster sample design
to produce a representative sample of public and private high
school students in grades 9–12 in the 50 states and DC. The
national YRBS has been conducted biennially since 1991. In
2011, a total of 15,425 questionnaires were completed in 158
schools. YRBS questionnaires are self-administered; students
record their responses on a computer-scannable booklet or
answer sheet. In 2011, the student response rate was 87%,
the school response rate was 81%, and the overall response
rate was 71%.