This study was a single-center, prospective cohort study undertaken at Siriraj hospital between March 2020 to November 2022. Eligible participants were required to collect their stool samples one to two days before the bowel preparation. The stool was sent for fresh smear examination, quantitative FIT (OC-SENSOR, EIKEN CHEMICAL, Japan), and quantitative fecal calprotectin (EliA Calprotectin 2, Phadia, Sweden). Blood samples were obtained on the day of the colonoscopy and were tested for complete blood count, albumin, and C-reactive protein (CRP) levels. In addition, clinical information was obtained, including alarm features such as the age of onset older than 50 years, rectal bleeding, anemia, significant weight loss, and family history of colorectal cancer. Colonoscopic findings and histopathological findings were used as the reference standard for diagnosis. We analyzed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for diagnosing significant ileocolonic lesions, including colorectal cancer, advanced adenoma, and colitis, of each diagnostic modality comparing to the reference standard.
