document.write( "Question 1193250: The table below shows the results of a new screening test for Crohn's disease.
\n" ); document.write( "Has Crohn's Does not have Crohn's
\n" ); document.write( "Test Positive 56 33
\n" ); document.write( "Test Negative 4 307
\n" ); document.write( "What percentage of the individuals in the study were false negatives?
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Algebra.Com's Answer #825253 by math_tutor2020(3817) $\"\"$ $\"About$

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\n" ); document.write( "Given Data Table:\n" ); document.write( "\n" ); document.write( "

	Has Crohn's	Does not have Crohn's
Test Positive	56	33
Test Negative	4	307

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\n" ); document.write( "\n" ); document.write( "Next, compute the row and column totals (eg: 56+33 = 89 people test positive along the first row)\n" ); document.write( "\n" ); document.write( "

	Has Crohn's	Does not have Crohn's	Total
Test Positive	56	33	89
Test Negative	4	307	311
Total	60	340	400

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\n" ); document.write( "\n" ); document.write( "Definitions:

When the test says negative, it is claiming the person does not have the disease.
A false negative is when the test reports \"negative\", but the reality is that the person does indeed have the disease. If the test was 100% perfect without any error, then the test should have reported \"positive\".

Based on those definitions, we can see that 4 people who have Crohn's tested negative (when they should have tested positive). This is out of the 400 people total in the sample.
\n" ); document.write( "4/400 = 0.01 = 1% is the false negative rate.\r
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\n" ); document.write( "\n" ); document.write( "Answer: 1%
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