Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Davis KL, Meyers J, Zhao Z, McCollam PL, Murakami M. High-risk atherosclerotic cardiovascular disease in a real-world employed Japanese population: prevalence, cardiovascular event rates, and costs. J Atheroscler Thromb. 2015 Dec 1;22(12):1287-304. doi: 10.5551/jat.28852