Lower gastrointestinal bleeding (LGIB) is a common presentation in the Emergency Room. It can deteriorate into severe adverse event. However some are discharged before these events occur. The Oakland-Jairath score was developed to help determine which patients can be safely discharged and which should be admitted from the ER to the hospital. The score did well in its development, but now needs to be externally validated by other independent cohorts. The limitations of the first study will be addressed in our study. The goal of this study is to perform the first prospective, multi-centered, external validation of the Oakland-Jairath risk score on an independent and diverse population who present to the emergency room with LGIB.

Of critical importance in the approach to care of these patients is differentiating the majority of people who can be safely discharged for outpatient management from those who are at risk for serious adverse events and require hospitalization. Recently, Oakland and Jairath developed a clinical prediction rule for safe discharge among patients with LGIB using data from their UK National Audit. The next step in the development of a clinical prediction rule is external validation in independent cohorts. Measures of predictive accuracy for risk scores, such as the AUC, are overly optimistic when calculated from the derivation cohort from which the risk score was derived. Therefore, it is essential to evaluate its performance using independent and diverse validation cohorts. Thus, the goal of this study is to perform the first prospective, multi-centered, external validation of the Oakland-Jairath risk score on an independent and diverse population who present to the emergency room with LGIB. This is a prospective multi-centre observational study to externally validate the Oakland-Jairath LGIB risk score, herein referred to simply as the "risk score".

Consecutive patients presenting to hospital over a 6 month period will have their risk score calculated and followed for the development of an adverse outcome over a 28 day period. The risk score will be determined for research purposes only but will be shared with the treating physician if requested as the details of the risk score itself is within the public domain. Patients will be eligible regardless of discharge status and all admission decisions will be made solely by the treating physicians. To increase the diversity of the validation cohort, increase generalizability, and hasten recruitment, the study will be conducted at 4 centres: Western University, University of Alberta, University of Montreal, and McGill University.

Inclusion Criteria:

1. Presenting complaint of LGIB, defined as any of the following:

1. Bright red blood per rectum
2. Maroon coloured stool
3. Criteria A and B applies regardless if the blood is seen without stool, with stool of any consistency, or only on the toilet paper

Exclusion Criteria:

1. Age ≤ 18
2. Hematemesis, defined as bright blood or coffee ground emesis
3. Patients who developed LGIB while already admitted to hospital for any reason
4. Patients transferred between hospitals
5. Failure to obtain informed consent
6. Occult bleeding, defined as the presence of a positive FOBT/FIT or iron deficiency anemia in the absence of bright red blood per rectum or maroon coloured stool
7. Perceived inability to contact the subject by telephone or e-mail for the 28 day follow up assessment

Any adult person who presents with lower gastointestinal bleeding as defined by: bright red blood per rectum, and/or maroon coloured stool.