McFall, Stephanie L., Anne Conolly, and Jonathan Burton. “Collecting Biomarkers Using Trained Interviewers. Lessons Learned from a Pilot Study”. Survey Research Methods 8, no. 1 (March 28, 2014): 57-66. Accessed June 15, 2021. https://ojs.ub.uni-konstanz.de/srm/article/view/5471.