Two hundred (200) patients were examined by Bilateral Intern…

Two hundred (200) patients were examined by Bilateral Internal Carotid Arteries (ICA) Duplex Ultrasonography and Cerebral Angiography. Of these, 300 ICAs were correctly identified as being within normal limits, 80 ICAs were correctly identified as having significant stenosis, 15 ICAs were incorrectly considered to have significant stenosis by sonography and 5 ICAs were incorrectly considered to be within normal limits by sonography. The specificity of ICAs Duplex is ________

100 patients, Each one had a duplex Ultrasound exam and a CT…

100 patients, Each one had a duplex Ultrasound exam and a CT Angiography of LE Arterial system. 53 pts had a Femoral Arterial stenosis by US & CT, 15 pts had a Femoral Arterial stenosis  by US but no stenosis by CT, 22 pts had no significant Femoral Arterial stenosis by US & CT  10 pts had no significant Femoral Arterial stenosis  by US but did have a significant stenosis by CT. What is the number of false negatives?