CologuardĀ® screens adults 50 years or older, who are at average risk for colon cancer. Cologuard uses sDNA (stool DNA) technology, and it detects cancer and the highest-risk pre-cancers. It makes Cologuard the most accurate, noninvasive colon cancer screening test that you can rely on. Cologuard is not a replacement for diagnostic colonoscopy or surveillance colonoscopy in high-risk individuals. Any positive test result with Cologuard should be followed by a diagnostic colonoscopy.