Sensitivity , specificity , positive and negative predictive values , and accuracy per patient at the 4 mm threshold were 0.82 , 1.00 , 1.00 , 0.91 and 0.94 for filtered back projection , 0.85 , 1.00 , 1.00 , 0.93 and 0.95 for adaptive statistical iterative reconstruction , and 0.94 , 1.00 , 1.00 , 0.97 and 0.98 for model based iterative reconstruction , respectively .