Gastroenterology
Glasgow-Blatchford Score
Risk stratification of upper GI bleeding.
Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.
Background
The Glasgow-Blatchford score (GBS) is a risk-assessment tool applied at first presentation with upper gastrointestinal (GI) bleeding, before any endoscopy. It uses clinical and laboratory variables available on admission — blood urea, haemoglobin, systolic blood pressure, pulse, and the presence of melaena, syncope, hepatic disease or cardiac failure — to predict the need for intervention such as transfusion, endoscopic therapy or surgery. Unlike the Rockall score it requires no endoscopic findings, making it ideal for early triage. The score ranges from 0 to 23.
Interpreting the result
A higher score indicates greater likelihood of needing clinical intervention. A score of 0 identifies a very-low-risk group in whom outpatient management and deferred or no urgent endoscopy may be considered, as the risk of needing intervention is very low. Scores of 1–5 represent low-to-intermediate risk, while scores of 6 or more indicate higher risk that generally warrants admission and inpatient endoscopy. The score supports, but does not replace, clinical judgement and local pathways.
Worked example
A 50-year-old man with melaena, a urea of 9 mmol/L, haemoglobin of 115 g/L, systolic blood pressure of 108 mmHg and pulse of 96/min: Urea 8–9.9 (3) + Hb 100–119 men (3) + SBP 100–109 (1) + melaena (1) = 8. This is a higher-risk score requiring admission and endoscopy.
Pearls / pitfalls
- Only a score of 0 is reliably safe for outpatient management; some pathways use a threshold of 0–1, but follow local guidance.
- A raised urea out of proportion to creatinine is itself a clue to upper GI bleeding, reflecting absorbed blood.
- The score predicts need for intervention, not mortality — it is not interchangeable with the Rockall score.
- It does not capture all causes for admission; significant comorbidity, anticoagulation or social factors may justify admission despite a low score.
Evidence & validation
Derived and validated by Blatchford and colleagues, and subsequently shown in multiple cohorts to reliably identify very-low-risk patients (score 0). It is endorsed by NICE and the British Society of Gastroenterology for initial risk assessment in acute upper GI bleeding.
Frequently asked questions
What does a Glasgow-Blatchford score of 0 mean?
A score of 0 identifies a very-low-risk patient with a very low chance of needing transfusion, endoscopic therapy or surgery. Such patients may be considered for outpatient management with deferred endoscopy, subject to local policy and clinical judgement.
How is it different from the Rockall score?
The Glasgow-Blatchford score uses admission clinical and blood results to predict the need for intervention and can be calculated before endoscopy. The Rockall score, especially its full version, focuses on predicting rebleeding and death and uses endoscopic findings.
Why is urea included?
Blood from an upper GI bleed is digested and absorbed, raising the blood urea. A high urea, particularly relative to creatinine, supports the diagnosis and contributes points to the score.
Does a high score tell me the patient will die?
No. The score predicts the likelihood of needing clinical intervention, not mortality. A high score should prompt admission and endoscopy but does not by itself quantify the risk of death.
References
- Blatchford O, Murray WR, Blatchford M. A risk score to predict need for treatment for upper-gastrointestinal haemorrhage. Lancet. 2000;356(9238):1318–1321.
- NICE NG12 (formerly CG141): Acute upper gastrointestinal bleeding in over 16s: management.
About the creator
Blatchford O et al.
Related calculators
Need a calculator we don't have — or a custom tool?
We build evidence-led clinical calculators, dashboards and reference tools for teams.