400
All currently enrolled students were identified and women and men were divided into separate groupings. Women were assigned a number from 1 to 5,390 and men assigned a number from 1 to 6040 (there were 5,390 and 6040 women and men on the rolls respectively). Research assistants drew numbers with a computerized random-digit program, and contacted women and men and asked them if they would be willing to join the study, until by sampling with replacement, 400 women and 400 men had agreed to be in the study.
What is This is for a stratified random sample
The strata—male and female are described
The method of random sampling—using a computerized random digit generator is described
Who contacts them (a research assistant) is noted
How contact is made (by phone) is noted