Pros and cons of the at-home Cologuard test

Colon cancer, sometimes called colorectal cancer, is the third most common cause of cancer death in any gender. Fortunately, it can be detected and prevented with early screening methods, which you can start at age 45.

The preferred method of screening for colon cancer is colonoscopy, an imaging test that detects abnormalities in the colon. It is performed using a tube with a camera (colonoscope) inserted through the anus and rectum.

Another colon cancer screening method called Cologuard has gained popularity because it is less invasive and more convenient than colonoscopy. It was approved by the US Food and Drug Administration (FDA) in August 2014. With the COVID-19 pandemic, the use of Cologuard has become widespread because it can be done at home.

While Cologuard screening has some benefits, it also has drawbacks. A major problem is its lack of accuracy. Nor is it a substitute for colonoscopy.

This article will discuss the purpose of the Cologuard test, who are good candidates, how it differs from a colonoscopy, and more.

Purpose of Cologuard Testing

The Cologuard test uses stool samples to look for microscopic blood and altered DNA. The first is to collect stool samples at home using special containers. After you prepare a stool sample, send it to a lab for testing.

Cologuard looks for DNA changes that may indicate precancer polyp (growth in the lining of the colon) or colon cancer. It combines two tests: the Fecal Immunochemical Test (FIT) to look for trace amounts of blood and DNA to screen for abnormal cancer cells.

Colon cancer can be detected with Cologuard because the lining of the colon sheds cells several times a day. These cells end up in the stool. Abnormal cells from cancerous tumors or precancerous polyps can also be shed in the stool along with the blood of any ruptured blood vessels.

What are polyps?

Polyps are growths on the surface of the colon that can grow into cancer.

When to Consider Taking the Cologuard Test

Your healthcare provider may recommend Cologuard screening every three years after age 45. The test is recommended for people at average risk of cancer.

Average risk means you don’t:

  • Personal history of colon polyps or colon cancer
  • Colon cancer family history
  • Inflammatory bowel disease (Crohn’s disease and ulcerative colitis)

What is inflammatory bowel disease?

Inflammatory bowel disease is a disease that includes two chronic diseases of the gastrointestinal tract: Crohn’s disease and ulcerative colitis. These conditions can lead to long-term inflammation and symptoms such as diarrhea, abdominal pain, and rectal bleeding.

Who should get a colonoscopy

For some people, colonoscopy is a better option than Cologuard. People with a personal or family history of colon cancer or colon polyps or with inflammatory bowel disease should have a colonoscopy instead of using the Cologuard test.

Colonoscopy is also recommended when someone has signs and symptoms of colon cancer. Signs that indicate colon cancer include constipation or diarrhea, blood in the stool, changes in the shape or color of stool, rectal bleeding, and/or abdominal pain or cramping.

What are the symptoms of colon cancer?

Cologuard and colonoscopy

The main difference between Cologuard and colonoscopy is that Cologuard is non-invasive. Cologuard involves collecting stool samples at home and transporting them to a laboratory. The colon was not imaged, and the polyps were not removed. Also, the test does not require sedatives or anesthetics.

abnormal result

If the Cologuard results are abnormal, your doctor will send you for a follow-up colonoscopy.

Colonoscopy is an outpatient procedure in which you are given a sedative (medication given can make you drowsy and unconscious). Once you are sedated, your doctor will use a thin scope to look at the colon and remove any polyps. Removing polyps has been shown to reduce the risk of colon cancer.

Another difference between the two tests is preparation. Cologuard generally does not require any dietary or medication changes or other preparation prior to taking a stool sample. Colonoscopy requires bowel preparation (removal of all residue from the colon with diet and medication) so that the colon can be emptied for imaging.

A third difference between the two tests is how they detect polyps. Colonoscopy can detect all types of polyps. Cologuard rarely detects small early polyps and is best for detecting large, advanced polyps. Other differences between the two screening methods are test accuracy and cost.

Cologuard Accuracy

The Cologuard test has its drawbacks, mainly in terms of accuracy, especially when compared to colonoscopy.

According to data presented at the 2022 American Society of Clinical Oncology Symposium on Gastrointestinal Cancer (ASCO GI), Cologuard’s overall sensitivity (the ability to correctly identify a person as positive) for colon cancer is 95.2 percent. Other analyses showed a sensitivity of 83.3% for high-grade dysplasia (more severe precancerous lesions) and 57.2% for all advanced precancerous lesions.

2018 Journal Review Chronic Diseases and Translational Medicine Fecal sample testing was found to be less accurate than colonoscopy in detecting precancerous polyps and lesions. Also, stool tests are more likely to have false positives (positive results when there is no cancer), which is why doctors prefer to send patients to colonoscopies.

Insurance Coverage and Cologuard Fees

When used as a screening method, most health insurance plans and state-sponsored Medicaid coverage will pay for Cologuard.

The Affordable Care Act (ACA) requires all private insurers and Medicare to pay for colon cancer screenings because they are recommended by the U.S. Preventive Services Task Force. The ACA also prevents insurance companies from charging any out-of-pocket fees for preventive screenings.

If you are eligible for preventive colon cancer screening and you have insurance, you will most likely be able to get the Cologuard test without paying any copays or deductibles. If you are uninsured or not covered by your insurance, you may be eligible for a flexible payment plan or financial assistance program from the manufacturer of Cologuard.

The Hidden Cost of Positive Cologuard Results

according to a Forbes Reportedly, Cologuard costs $649. Colonoscopy costs about $2,200. While this appears to be a cost saving, Cologuard is checked more frequently, every year or every three years, while colonoscopies are only done every 10 years in people without polyps.

Also, if the Cologuard test is positive, your doctor will most likely order a colonoscopy to screen for cancer and remove any polyps. Your insurance company may also not code a follow-up colonoscopy as a screening test.

This means that the cost of the program may go toward your deductible, and you may have to pay a copay.

where to order

You will need a prescription for Cologuard from your healthcare provider. If you and your supplier think Cologuard is the best option, we will order a kit and ship it to your home. If you have any questions after the Cologuard kit arrives, you should contact your healthcare provider.

Description of Cologuard

The instructions for using Cologuard are very simple and screening can be done in just a few steps.

You should complete the test within five days of receiving the kit.

Exact Sciences, the manufacturer of Cologuard, provides the following instructions:

  • First remove only the items needed for the sample.
  • The stool sample should not be larger than the liquid bottle in the box.
  • Try not to get urine on the sample. You can prevent this from happening by emptying your bladder first. You should also avoid getting toilet paper or other materials on the stool sample.
  • Collect samples when you know you can return them within a day of collecting them.

To collect samples:

  • Place the large sample container in the toilet holder according to the instructions provided.
  • Sit on the toilet, defecate, and collect a stool sample in a large sample container.
  • Once you have the sample, remove the container from the toilet holder to a hard surface.
  • Scrape off the sample and add it to a small sample container.
  • Fill the large sample container with the included preservative.
  • Seal and label small and large sample containers. Pack the samples and send them to the laboratory according to the enclosed instructions.

For specific details on collecting samples, visit the Cologuard website for video instructions and step-by-step guides.

Once your sample is ready, place it at the UPS location. You can also call 844-870-8870 and Exact Sciences will arrange for a UPS pickup.

Explain your results and next steps

After the lab obtains your stool sample, they will evaluate it and send the results directly to your healthcare provider. The test result will be negative or positive.

A negative test means no significant levels of DNA or hemoglobin blood markers were found in stool associated with colon cancer or precancerous colon polyps.

A positive test means Cologuard has detected signs of precancerous polyps or colon cancer. If you test positive, your doctor will want you to schedule a follow-up colonoscopy.

Cologuard can have false negatives (tests that falsely say you do not have the disease) and false positives. A 2014 study reported in New England Journal of Medicine 13% of Cologuard results were found to be false positives and 8% were false negatives.

If you test negative, Cologuard must be repeated every three years. Once you test positive, your doctor will recommend a diagnostic colonoscopy for future screening.

Colonoscopy frequency

If you have never had any polyps, you can have a repeat colonoscopy every 10 years.


Cologuard is a non-invasive screening tool for colon cancer and precancerous polyps. It looks for changes in DNA and evidence of microscopic blood in stool. The tests are collected in the privacy of your own home. Once the sample is ready, send it to the lab for testing.

Cologuard is popular because it is less invasive and more convenient than performing a diagnostic colonoscopy. It also has drawbacks, including concerns about accuracy and cost.

VigorTip words

Both Cologuard and diagnostic colonoscopy have pros and cons. When it comes to which option is best for you, it’s important to understand the pros and cons of each screening method.

Contact your healthcare provider if you have any concerns or questions about Cologuard and colonoscopy, and your risk for colon cancer or precancerous polyps.

Frequently Asked Questions

  • Is Cologuard worth the effort?

    For some people, Cologuard is their best option. But Cologuard has some limitations compared to traditional colonoscopy. Discuss with your healthcare provider whether Cologuard is the best option for you or if you should opt for colonoscopy.

  • How much stool is needed for the Cologuard test?

    The sample size required for the Cologuard test is small. The sample you send to the lab should be at least the size of a grape.

  • What are other alternatives to colonoscopy?

    There are other tests for colon cancer and precancerous polyps.

    These include stool immunochemical testing (blood testing on a small stool sample), fecal occult blood testing (blood testing on a small stool sample), sigmoidoscopy (using a flexible endoscope to look at the last third of the colon), and CT (Computed Tomography) Colonography (advanced X-ray imaging of the colon).

    understand more:

    Colon Cancer Screening: Tests and Recommendations