would take approximately 15–30 min to complete. [Of note, we considerably shortened the survey in the spring based on focus group feedback that survey completion took closer to an hour and that this was the major deterrent to participation.] Upon completion of the survey, students went to a central site at the university to collect payment ($10 and a free “Spit for Science” t-shirt) and provide a saliva DNA sample (hence the “spit” in Spit for Science) for which they received another $10. They also had the option to take informational materials about the DNA component and return at a later time. Students had the option of participating in the survey portion of the project and not the DNA component. We also scheduled “dorm visits” where the research team was available at various residence halls at pre-specified times to give payments and collect DNA in an effort to minimize subject burden.
