Question
Hepatitis €No Hepatitis CROW TOTALTattoo(s)25113No tattoo491513Column Total579626
Hepatitis € No Hepatitis C ROW TOTAL Tattoo(s) 25 113 No tattoo 491 513 Column Total 579 626
Answers
A study by the University of Texas Southwestern Medical Center examined 626 people to see if an increased risk of contracting hepatitis C was associated with having a tattoo. If the subject had a tattoo, researchers asked whether it had been done in a commercial tattoo parlor or elsewhere. Write a brief description of the association between tattooing and hepatitis C, including an appropriate graphical display.
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All right. So for this one, we're focusing on, um, someone testing positive, but, um, not having the hep C. So that probability is two out of 11 55 which is 0.173 Um, And so the bad thing about this is the additional question. What's the negativity here? If a person without help seek test positive, it's going to cost them stress that they don't need tohave. That's unnecessary and possibly add additional testing That is unnecessary and money. So I mean, think about insurance costs and not everything always gets covered. So it could even lead Thio extra money being spent for a test that came back as a false positive, so
Okay, so for this problem we're focusing on given that there, uh, we're testing with with positive or negative for hep C. What's the probability of them testing negative when they really do have hep C. So that's gonna be 10 out of 3 45 which is 450.29 And so the problem or the negatives with this is a person's told that they don't have hep C when in fact, they dio they're losing time. Thio hopefully fight this and get treated for their symptoms could be getting worse. So it's definitely a very dangerous situation if you actually a Pepsi and then you get a false negative and, um, you're not getting treated for that hep C. So, um, definitely
All right. He said, for this one, we're still talking about the helps Ease of positive tests versus negative tests were trying to figure out the probability of them of this test testing positive for the hep C. So that probability is 3 35 out of the 3 37. And so that's going to be 0.994 And so, since this is a higher result, um, uh, it appears to be an effective test, since it's almost over 99% accurate.
Well if we let A be the event that the patient was treated with ribavirin plus interferon alpha. Okay I'm not a doctor. So we're just gonna say treatment. And for B we're going to note that the response was complete. So now we have that um the magnitude of a. Is going to be 21 people. And for B. This is going to be 22. Yeah. Yeah. So for part A. It is 21 party. We're looking at the number of reactions. So A. And B. Yeah. Uh This is going to be the number of people that had alfalfa or interfere on alpha. And the response was complete. So this is going to be 16. And then we're going to look at the other one, A Union Beat. So we're gonna be looking for one or the other And we have 21 people in a. And we have six from the other group. And then we don't have any from a complete response. So this gets us 27. and then for party or looking at the intersection of the compliments so those that weren't treated and did not respond. So this is going to be 19 minus the six that did plus 20 And this gets us 33.