Assume that a certain test for group A Streptococcus has reported sensitivity and specificity of 90% and 98%, respectively, and the estimated prevalence for group A Streptococcus infection in acute pharyngitis is 5%.What is the positive predictive value of this test?
A)99.5%
B)30%
C)90%
D)70.3%

Question

Quizplus · Accepted Answer

11ea57a1_5613_5528_abe1_7928a86fe7a0_TB4772_00 
where PPV = positive predictive value
P = prevalence of disease being tested
Se = sensitivity of test
Sp = specificity of test

Assume That a Certain Test for Group a Streptococcus Has