The table below summarizes the results of a clinical trial testing a diagnostic device and its ability to determine if a patient with traumatic brain injury has bleeding in their brain. The actual clinical condition of the patient against which the device is being compared is a CT scan where a positive scan (CT+) means that they have bleeding in their brain; CT- means they don't have bleeding in their brain. The new diagnostic test will be useful if it can eliminate unnecessary CT scans by determining which patients don't have bleeding in their brain. Total number of patients Patients with positive test and CT+ 720 144 Patients with positive test and CT- 273 Patients with negative test and CT+ 12 Patients with negative test and CT- 291 1. Construct a confusion matrix for the accuracy of the diagnostic test. 2. Calculate the sensitivity, specificity, PPV and NPV for the diagnostic test. Which of these metrics is most important for the intended use of the device? Comment on the results.

The table below summarizes the results of a clinical trial testing a diagnostic device and its ability to determine if a patient with traumatic brain injury has bleeding in their brain. The actual clinical condition of the patient against which the device is being compared is a CT scan where a positive scan (CT+) means that they have bleeding in their brain; CT- means they don't have bleeding in their brain. The new diagnostic test will be useful if it can eliminate unnecessary CT scans by determining which patients don't have bleeding in their brain. Total number of patients Patients with positive test and CT+ 720 144 Patients with positive test and CT- 273 Patients with negative test and CT+ 12 Patients with negative test and CT- 291 1. Construct a confusion matrix for the accuracy of the diagnostic test. 2. Calculate the sensitivity, specificity, PPV and NPV for the diagnostic test. Which of these metrics is most important for the intended use of the device? Comment on the results.

College Algebra (MindTap Course List)

12th Edition

ISBN:9781305652231

Author:R. David Gustafson, Jeff Hughes

Publisher:R. David Gustafson, Jeff Hughes

Chapter6: Linear Systems

Section6.2: Guassian Elimination And Matrix Methods

Problem 84E: Explain the differences between Gaussian elimination and Gauss-Jordan elimination.

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