Question

(Please use a separate piece of paper to calculate the answer for this problem.) A study to determine the sensitivity and specificity of a new test for macular degeneration is conducted on 2430 people. Macular degeneration occurs at a rate of 16.72 percent. Your sample has the same prevalence of macular degeneration. You find that 377 people with macular degeneration tested positive with the new test. You also have a total of 561 positive test results in your study. CALCULATE THE POSITIVE PREDICTIVE VALUE of this test under these circumstances. Group of answer choices 83.29% 98.45% 67.20% 92.86% 23.09%

Answer 1

Answer:

$67.20\%$

Step-by-step explanation:

Given

$n =2430$ --- sample

$r = 16.72\%$ --- degeneration rate

From the findings, we have:

$p = 377$ --- tested positive

$t =561$ --- total test

Required

The positive predicted value (PPV)

This is calculated using:

$PPV=\frac{Positive}{Total}$

i.e.

$PPV = \frac{377}{561}$

$PPV = 0.6720$

Express as percentage

$PPV = 0.6720 * 100\%$

$PPV = 67.20$