Fischer A, Zimovetz E, Ling C, Esser D, Shoof N. Humanistic and cost burden of systemic sclerosis: a review of the literature. Autoimmun Rev. 2017 Nov;16(11):1147-54. doi: 10.1016/j.autrev.2017.09.010
Groenwold R, Uddin M, Roes K, de Boer A, Rivero-Ferrer E, Martin E, Gatto N, Klungel O. Instrumental variable analysis in randomized trials with non-compliance and observational pharmacoepidemiologic studies. OA Epidemiology. 2014 May 9;2(1):9.