A study was done to evaluate a new serologic screening test for human immunodeficiency virus (HIV) infection. A total of 1000 people were randomly selected from the population, screened using the new test, and screened again using the gold standard (i.e., Western blot analysis) to determine true infection state. The findings are as follows:
What is the sensitivity of this new serologic screening test?

Question

A study was done to evaluate a new serologic screening test for human immunodeficiency virus (HIV) infection.  A total of 1000 people were randomly selected from the population, screened using the new test, and screened again using the gold standard (i.e., Western blot analysis) to determine true infection state.  The findings are as follows:
 What is the sensitivity of this new serologic screening test?

Quizplus · Accepted Answer

Sensitivity and specificity are used to measure a test's validity. Sensitivity is defined as the proportion of positive test results among the subjects with the disease. Specificity is defined as the proportion of negative test results among the subjects without the disease. 11ec25c8_d2ef_55d3_bc81_d9532b0f6732_MD0003_00 Sensitivity = TP / (TP + FN) = A / (A + C) Sensitivity determines how well the test identifies the people with the disease. It is usually the first test used, similar to the use of a screening test when there is a public health threat. The true-positive rate describes the sensitivity of the test. Specificity = TN / (TN + FP) = D / (B + D) Specificity determines how well the test identifies the people without the disease. The true-negative rate describes the specificity of the test. A perfectly valid diagnostic test should have sensitivity and specificity equal to 1, but this is seldom possible. The more sensitive the test, the less specific it is (and vice versa). In this example, the sensitivity is 140/180. Educational objective: Know how to calculate the sensitivity and specificity of a test.

A Study Was Done to Evaluate a New Serologic Screening