Importance Of Accuracy Of A Diagnostic Test

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When researching about mathematics in a medical environment, I found that one can use probability to calculate how accurate a medical test is exactly. There are many factors that play into the reason for level of accuracy of the test. Despite the fact that results will vary from laboratory to laboratory, one of the highest accuracy rates is 97%, for which was well-known and thought of as prestigious and high quality. However, this raises the point of that is essential in the understanding of the accuracy of any given diagnostic test. The accuracy of the diagnostic tests are derived from statistical distribution. However, this brings in the question according to diagnostic tests of how much error is acceptable and does the % error…show more content…
This is why if a medical test provides a correct result 98% of the time then it can be said to be “98% accurate.” In order to test out the medical test accuracy in a general population (fictional) let’s come up with a heart disease, for example, Pepitolitis, which is known to affect approximately 5% of all students aged 15-17. The doctor has developed a medical test in order to diagnose this indisposition. The test is said to be “98% accurate.” A large school district decides that they will test all of the 30000 students within the age group of 15-17. The table below shows how the results would come out. In this fictional school district, 28500 students did not have the disease, but only 27960 will test negative. 99.89% of the negative test results are correct because 27930 out of 27960 is 99.89%. These are called the true negatives, which is a test result that is one that does not detect the condition when the condition is absent. The table also shows the false positives, which is a test result which incorrectly indicates that a particular condition or attribute is present. In this case, the false positives would be that 1500 students out of 30000 students, 2040 students will test positive. So in this case about 26.47% of the positive results is incorrect, which is not accurate at all! Using Bayes’ theorem, it will be possible to find the probability of event A given event B,
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