A new study has found that at-home screening tests for colon cancer are not as effective in detecting pre-cancerous polyps compared to a colonoscopy.

Researchers focused on the fecal immunochemical test or FIT in the JAMA Open Network study. The test provides people with a small brush to gather a toilet water sample from a bowel movement.

It is then tested for hidden blood in the stool, which can be an early sign of cancer.

Researchers say FIT is appealing to people because it can be done at home and completed with one stool sample. There is no prep required and people do not need to follow a special diet or take specific medication. It is also inexpensive.

Doctors say FIT has shown to detect 24% pre-cancerous polyps.

At-home stool DNA test like Cologuard were shown to find 42% of pre-cancerous polyps. That test asks for a stool sample to be packaged and sent to a lab, where DNA and blood are tested.

The study's lead author says the tests can be helpful though.

"We estimate that the tests are around 33% effectiveness in reducing death from colorectal cancer. But also more importantly, it's effective across racial and ethnic groups that we study, including black people, white people and Asian people," says Dr. Chyke Doubeni.

Doctors want to emphasize that a colonoscopy is still the gold standard, as it has shown to find 95% of pre-cancerous polyps.

If an at-home test shows any signs of colorectal cancer, a patient is asked to schedule a colonoscopy. Doctors say people who are at average risk for colorectal cancer should start getting screened at the age of 45. Anyone considered high risk should be screened earlier.