Feasibility of mailed biomarker data collection among U.S. young adults: Saliva-based cotinine and self-reported nicotine use.

backgroundNationally representative self-report studies are the standard for data on the prevalence of substance use. Newly emerging biomarker assessments can add objective measurements of exposure. However, biomarker assessment has typically depended on in-person sample collection. The current study examined whether young adults in a national sample would be willing and able to provide a saliva sample via mail, and the correspondence of cotinine in the saliva sample with self-reported vaping and smoking.

methodsData collection for the Monitoring the Future (MTF) Vaping Supplement was from September to November 2020. Eligible participants (N = 4358) were selected from a nationally-representative sample of US 12th-grade students in MTF in spring 2019. The MTF Vaping Supplement surveyed individuals nationally about one year after the 12th grade MTF survey (in 2020, mean age = 19.6 years; N = 1244). Survey weights accounted for design and attrition.

resultsOf those surveyed, 66.2% consented to provide a saliva sample and, of those, 73.8% mailed a sample. There were no significant differences in providing a saliva sample across any demographic characteristic, but those who reported nicotine use were less likely to provide a sample. Cotinine cut-off measures of > 3 ng/mL and > 10 ng/mL had good correspondence with self-reported measures.

conclusionsResults support the feasibility of collecting saliva via the mail in a national sample and the validity of data collected in this way. These findings support future research innovations to expand existing survey research protocols to include biomarker data collection in representative samples of young adults.