The sensitivity and specificity of a commonly used fecal immunochemical tset for detection of colorectal cancer is 80 % and 90 % respectively. Prevelance of CRC in people aged 45-54 is 1 %. What is likely hood of a 50 yo testing + on FIT but does not have CRC?

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1. To do this assume 1000 hypothetical people tested. 2. We know 1 % is prevalence so 1 % of 1000 = 10 people who CRC is positive. 3. Since we know sensitivity is 80 % we know of the 10 people who has CRC only 80 % will be detected = 8 True positive cases. 4. The other 2 not detected from that 10 are the false negatives. 5. From the 90 % specificity we know that 90 % of the 990 people without CRC will test negatively = 891 = True negatives. 6. The remaining number is 99 = the number of false positive. 7. Soo positive predictive value = True positives / (TP + FP) =8 / 107 = 7% this means that if a person has a + FIT there is a 7 % chance they have cancer and a 93 % chance they dont have cancer. *** to do this question break it down into the parts you need draw a table and include in it the follwoing True positive False positive True negative False negative and the totals in each column/row from there fill it out and calculate the positive predicive value and you are done. Remember PPV = TP / (TP + FP) yes these questions suck and are bullshit

The sensitivity and specificity of a commonly used fecal immunochemical tset for detection of colorectal cancer is 80 % and 90 % respectively. Prevelance of CRC in people aged 45-54 is 1 %. What is likely hood of a 50 yo testing + on FIT but does not have CRC?

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The sensitivity and specificity of a commonly used fecal immunochemical tset for detection of colorectal cancer is 80 % and 90 % respectively. Prevelance of CRC in people aged 45-54 is 1 %. What is likely hood of a 50 yo testing + on FIT but does not have CRC?

❤ If you liked Fatskills, consider supporting us by checking out The Life Manuals You Never Got.

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Without work one finishes nothing. - Ralph Waldo Emerson© 2026 Fatskills.com

All trademarks, logos and brand names are the property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, trademarks and brands does not imply endorsement.

About | Explore | User Guide | Topics | Subjects | Doubt Solver | Career Aptitude Test | Answers | Free Tools | What Should We Know?
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Without work one finishes nothing. - Ralph Waldo Emerson
© 2026 Fatskills.com