The most commonly used test for HIV has a sensitivity of 0.997 and a specificity of...

The most commonly used test for HIV has a sensitivity of 0.997 and a specificity of 0.985. In other words, a person infected with HIV will test positive for the virus 99.7% of the time while a person NOT infected with HIV will test NEGATIVE for the virus 98.5% of the time. Research current rates of infection for the indicated population in order to answer the following questions.

If a US randomly selected US resident is tested for HIV and the test shows a positive result, what is the probability that they are infected? In other words, what is the probability that a positive result is accurate?
If a US randomly selected US resident is tested for HIV and the test shows a negative result, what is the probability that they are infected?
Comment on the results from the previous questions. If you were to test positive for HIV, would it make sense to get retested? What if you were to test negative?
What is the probability that a positive HIV test is accurate for a resident of Pakistan? How likely is a negative test to be accurate?
What is the probability of a positive vs. a negative result being accurate in the Democratic Republic of Congo?
What is the probability of a positive vs. a negative result being accurate in Lesotho?
The science of diagnostic testing is basically the same no matter what you are testing for. As of 2015, approximately 7% of Americans had consumed cannabis in the last month. At the same time, approximately 0.5% of Americans had consumed cocaine in the past month. How much would you trust a positive test result for each drug?

Expert Solution

orchestra answered 1 year ago

Suppose a test for a disease has a sensitivity of 80% and a specificity of 95%....

Suppose a test for a disease has a sensitivity of 80% and a specificity of 95%. Further suppose that in a certain country with a population of 1,000,000, 21% of the population has the disease. Fill in the accompanying table. -------------------Has disease |Does not have disease| Totals Test positive Test negative Totals

A newly developed test for coronavirus has sensitivity 0.90 and specificity 0.85. Sensitivity is the probability...

A newly developed test for coronavirus has sensitivity 0.90 and specificity 0.85. Sensitivity is the probability of a positive result given that a person has the virus, and specificity is the probability of a negative result given that a person has no virus. Suppose that 12% of the population has the coronavirus. If the test gives you a positive result, what is the probability that you actually have the virus? Show your work.

Suppose that a medical test for a certain disease has a sensitivity and specificity of 93%....

Suppose that a medical test for a certain disease has a sensitivity and specificity of 93%. The test is applied to a population of which 11% are actually infected by the disease. 1. Calculate the NPV and the PPV. 2. What percent of the total population will test positive who are disease-free? 3. What percent of the total population will test negative who have the disease?

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How to calculate 95% CI with sensitivity and specificity That is sensitivity, specificity, prevalence has been given and 95%CI needs to be calculated, but how???

In the following scenarios identify the Reality, the test, Sensitivity, Specificity, False Negative, and False Positive....

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Obtain at least three test methods for Covid-19 and obtain their sensitivity or specificity. You will...

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staybolts are most commonly used in ------ boilers.

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Research amniocentesis for Down Syndrome. What are the sensitivity and specificity for amniocentesis for Down Syndrome...

Research amniocentesis for Down Syndrome. What are the sensitivity and specificity for amniocentesis for Down Syndrome screening? Provide your reference/source.

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