Gracia Baena JM, Calaf Vall I, Zielonka M, Marsal Mora JR, Godoy P, Worner Diz F. Risk factors and comorbidities associated with severe aortic stenosis: a case-control study. Rev Clin Esp. 2021 May 23;221(5):249-57. doi: 10.1016/j.rce.2020.01.010.
DiTrapani J, Rockwood N, Jeon M. Explanatory IRT analysis using the SPIRT macro in SPSS. TQMP. 2018;14(2):81-98. doi: 10.20982/tqmp.14.2.p081