| Technique | Advantages | Disadvantages |
| Radionuclide imaging | Noninvasive Sensitive to low rates of bleeding Can be repeated for intermittent bleeding | Has to be performed during active bleeding Poor localization of bleeding site Not therapeutic Not widely available |
| CT angiography | Noninvasive Accurately localizes bleeding source Provides anatomic detail Widely available | Has to be performed during active bleeding Not therapeutic Radiation and IV contrast exposure |
| Angiography | Accurately localizes bleeding source Therapy possible with super-selective embolization Does not require bowel preparation | Has to be performed during active bleeding Potential for serious complications |
| Colonoscopy | Precise diagnosis and localization regardless of active bleeding or type of lesion Endoscopic therapy is possible | Need colon preparation for optimal visualization Risk of sedation in acutely bleeding patient Definite bleeding source (stigmata) infrequently identified |
