When applying the thresholds computed by ROC analysis to achieve 100% sensitivity, our rule had the highest specificity at 56 (95% CI; 41.3 - 70.0), followed by Spanos (24, 95% CI; 13.1 - 38.2) Oostenbrink (8, 95% CI; 2.2 - 19.2) Bonsu (8, 95% CI; 2.2 - 19.2) Hoen (4, 95% CI; 0.5 - 13.7), while Freedman, Nigrovic, Thome, Brivet, Schmidt, Cauwer, Chavanet and Tokuda rules could not be achieved at 100% sensitivity.