WBR0418
| Author | [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Alison Leibowitz)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Biostatistics/Epidemiology |
| Sub Category | SubCategory::Vascular |
| Prompt | [[Prompt::. The following table displays the results of a study investigating a new test in diagnosing aortic stiffness. Which of the following are the approximate sensitivity and specificity of the new test?
|
| Answer A | [[AnswerA::Sensitivity = 83%
Specificity = 67%]] |
| Answer A Explanation | [[AnswerAExp::Sensitivity (%) = TP/ (TP+FN) x 100 = 83%
Specificity (%) = TN/ (TN + FP) x 100 = 67%]] |
| Answer B | [[AnswerB::Sensitivity = 83%
Specificity = 71%]] |
| Answer B Explanation | AnswerBExp::71% corresponds to the positive predictive value (PPV). PPV is calculated by the following equation: PPV = TP/ (TP+FP) |
| Answer C | [[AnswerC::Sensitivity = 83%
Specificity = 83%]] |
| Answer C Explanation | AnswerCExp::Both values correspond to sensitivity. |
| Answer D | [[AnswerD::Sensitivity = 67%
Specificity = 83%]] |
| Answer D Explanation | AnswerDExp::The inverse is true. |
| Answer E | [[AnswerE::Sensitivity = 67%
Specificity = 67%]] |
| Answer E Explanation | AnswerEExp::Both values correspond to specificity. |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::Sensitivity (%) = TP/ (TP+FN) x 100 = 100/(100+20) x 100 = (100/120) x 100= 83%
Specificity (%) = TN/ (TN + FP) x 100 = 80/(80+40) x 100 = (80/120) x 100 = 67%
|
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Specificity, WBRKeyword::Sensitivity, WBRKeyword::calculation, WBRKeyword::equation, WBRKeyword::study, WBRKeyword::aortic stiffness |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |
