Some issues concerning the statistical evaluation of a screening test: the arfi ultrasound case

In this paper we analyze some issues concerning the statistical evaluation of a screening test for classification. The case study is ARFI, an ultrasound device recently introduced, and used for the evaluation of liver fibrosis. First, we present a simple statistical evaluation based on a novel index that compare two competitors with respect to a gold standard, and then we propose a procedure that determines a table with the “acceptable” number of measurements to get an “accurate” diagnosis using the ARFI device.