Question

Assume 50% of the world's population has a particular genetic condition. A blood test for the condition is available, but it is not 100% accurate. For those who do not have the genetic condition, the blood test will return a positive result 5% of the time. Additionally, for those who have the genetic condition, the test returns a negative result 8% of the time. Consider the experiment that an individual is randomly selected and tested for the genetic condition. Define the following events: C c PT NT = = = - an individual has the genetic condition, an individual does not have the genetic condition, a positive blood test, and a negative blood test. Complete the following table of likelihood probabilities. = 0.08 P(NTC) P(PTC) False negative: True positive: False positive: True negative: = 0.95 P(PTC) The sensitivity of the P(NTC) , and its specificity is P(PTC) What is the positive ue? 0.52 O 0.56 0.78 0.95 What is the negative predictive value? 0.91 0.92 0.96 0.88

Answer 1

=) PLC) = 50% -0.5. F: PLC) -0.5./-> a) But we fe now the formula for P(c) is, =) PCC): 1-PCC) = 1-0.5 = 0.5 A. PCC) 20. 5 6 ) from the 3 And we le now Cliven clata the negative test result is PCRTIC) - 8% - PCNI/C) - -0.08. 1. PCNT/C) = 0.08) — 6) Now, we fenow the formula is, PCPT/C) - 1-PCPTC) = 1- PONTIC) : 1-0.08 PT Pipile) . 0.921 . PLAT/C) 20.921

positive result., =) Now, we ie, are taking the PCPTIC) - 5"/ 20.05 1 :: PCPTIC) - 0.05.) → (e) Now, P (NTIC) = |- PCNTCC) = 1-PCPTLC) = 1-0.05 = 0.95 TE. PONTIC") - 095 7 1f). =) Now, we need to complete the given below Conditions. i) False negative PONTIC) = 0.08 1) Tsiue positive PCPTIC) = 0.092. 1) Torce negative Blaste) - Oros); PONTIC“)=0-95. iv) False positive PCPTIE) = 0.06 what is the positive predictive value] » The value is =) (Pentle') :0.95 27

- 2 what i - The ų the negative predictive Value? negative predictive value is, IPC PTIC) = 0.92