ALL ABOUT ACCURACY

So you want to use a Cologuard® test

But you have questions. Maybe about its accuracy, or how it compares to other use-at-home stool tests – or what Cologuard is to begin with. Let’s get you answers so you can get screened for colon cancer, especially if you’re 45 or older and at average risk.

By Exact Sciences Corporation | December 19, 2025

A man holds a Cologuard box in his living room.
Illustration of what components are included in a Cologuard box.

What's inside your Cologuard box. 

Once you’re done, it’s important to box and ship your kit right away, ideally on the same day or the next at the latest. To do this, you can schedule a pickup with UPS®, or drop it off at the nearest location to you. Pro tip: To avoid shipping delays, use your kit after the weekend or the holidays.


Once the lab receives your kit, it’ll take 8-10 days to get your test result.

What about my results? Will a positive one mean I have colon cancer?

Okay, let’s talk test results. With the Cologuard test, you will either get a negative or a positive result.


Negative: You don’t have to screen for the next 3 years, as recommended by the American Cancer Society.2


Positive: This is not a colon cancer diagnosis. It simply means that abnormalities were detected, and you need to undergo further testing via a colonoscopy. The best thing to do is to share your test result and discuss next steps with your doctor.

Wait, how accurate is Cologuard? I also read something about false positives and negatives. What are those?

In a clinical study of 10,000 people, ages 50-84 years old with an average risk for colon cancer, the Cologuard test found 92% of all colon cancers3 and 94% of all stage 1 & 2 cancers.3-5


When compared to a fecal immunochemical test  (FIT), Cologuard detected 2x more advanced precancerous lesions4# and 9x more sessile serrated lesions.4** Research has shown that due to its higher sensitivity and improved adherence, in both the initial screening and follow-up colonoscopy, Cologuard is the superior screening option versus a FIT.4*


When it comes to false positives and negatives, they do occur with Cologuard. Think of a false positive as a false alarm, while a false negative means something was missed during testing. In the same study above, 13% who did not have colorectal cancer or advanced adenomas received a positive result (false positive), and 8% of patients with colon cancer received a negative result (false negative).


Why does this happen? It’s important to note that no test is spared from these errors. No test is 100% accurate at any given time – such is the nature of scientific and diagnostic testing. This is why it’s crucial to discuss your results with your doctor, who can order additional tests if needed, based on your symptoms and medical history.

So…can Cologuard and all other stool tests be a substitute for a colonoscopy?

No, sorry. It’s important to keep in mind that stool tests can detect colon cancer, but they cannot prevent or cure it. A positive stool test result requires a follow-up colonoscopy, where doctors can examine the colon and remove polyps right then and there.


Stool tests are recommended for people 45+ with an average risk of colon cancer. High-risk individuals include those who have a family or personal history of colorectal cancer, and have received a cancer diagnosis in the last six months.


Included as well are people who have certain medical conditions such as IBS, Crohn’s disease, or chronic ulcerative colitis. If you have these conditions, you are not advised to use stool tests, and should get a colonoscopy instead.

Speaking of stools, is it true that having pencil-thin ones is a definite sign of colon cancer?

Nice segue, by the way, and the answer is pencil-thin stools do not automatically mean colon cancer. However, they are a potential symptom, especially if they are accompanied by other symptoms, such as blood in the stool, unexplained weight loss, stomach pain, or a drastic change in bowel habits. If having pencil-thin stools is unusual for you, or if they persist, it’s highly advised that you see a doctor so they can figure out what’s going on, and what needs to be done. It’s a good idea to get screened, even if you don’t have noticeable symptoms.

Hmm…are there other noninvasive stool tests I can use at home?

Yes, as mentioned above, there’s the FIT and the Guaiac-based fecal occult blood test (gFOBT). Both are over-the-counter tests that detect occult (hidden) blood in the stool. You can use them at home and send your sample back to a lab for testing.


The FIT and the Cologuard test are similar in that neither requires prep, medication, or a special diet.  Meanwhile, a gFOBT needs you to avoid certain medications such as NSAIDS and vitamin C, as well as red meat and raw fruits and veggies days before testing.


While Cologuard is prescription-based, it is also the only FDA-approved stool DNA test and is covered by most insurance plans, including Medicare.

I’m ready to get screened for colon cancer. How do I get Cologuard?

First of all, congrats and well done. Colon cancer is often considered the most preventable, yet least prevented cancer.6 So the decision to get screened means you’re taking care and taking charge of your health. And yes, if you’re 45 or older and at average risk, now is the best time to begin your journey.


Let’s begin by confirming your insurance covers Cologuard. Once that’s done, let’s get your request in. You can also ask your doctor to write a prescription and order one on your behalf.


If you have more questions – or maybe you have topics that weren’t covered in this guide – don’t worry, our Customer Service is happy to help. Every day, from 6 AM to 10 PM CT, just give us a call at +1 844-870-8870.