Fig. 3From: Defining competency in flexible cystoscopy: a novel approach using cumulative Sum analysisCumulative Sum (CUSUM) for identification of trigone and ureteric orifices (n = 383). Acceptable failure rate set at 0.05 and unacceptable failure rate at 0.15. Type I and II error rates 0.10. Each horizontal line on the y-axis represents a control line (h = 1.81)Back to article page