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989 Clinical Tools

AGA IPMN Risk Stratification (2015)AIMS65 Score APACHE II (AP-specific application)ASGE Choledocholithiasis Risk Stratification ATLAS Score (CDI Treatment Response)Adenoma Detection Rate (ADR) Benchmark Amsterdam II Criteria (Lynch)Anorectal Manometry Interpretation (ARM)Aronchick Bowel Preparation Scale BISAP Score Barrett's Dysplasia Grading (Vienna Classification)Boston Bowel Preparation Scale (BBPS)Bristol Stool Form Scale CD Perianal Disease Activity Index (PDAI)CDI Severity Classification (IDSA/SHEA 2021)CT Severity Index (CTSI — Balthazar)Caecal Intubation Rate (CIR) Benchmark Cambridge Classification (CP — ERCP/EUS/CT)Celiac Disease Serology Interpreter Chicago Classification v4.0 (HRM)Colorectal Cancer TNM Staging (AJCC 8th Edition)Colorectal Submucosal Invasion (Haggitt / Kikuchi)Correa Cascade Staging Cotton Criteria (ERCP Complications)Crohn's Disease Activity Index (CDAI)Crohn's Disease Endoscopic Index of Severity (CDEIS)DeMeester Score (Reflux Monitoring)Distal Contractile Integral (DCI) Calculator Dukes / Modified Astler-Coller Staging (CRC)ERCP Post-Procedure Pancreatitis Risk Score ESD/EMR Curative Resection Criteria (Gastric)Eckardt Score (Achalasia)FODMAP Reintroduction Protocol Indicator Faecal Calprotectin Interpretation Faecal Incontinence Severity Index (FISI)Forrest Classification (Peptic Re-bleed Risk)Fukuoka Consensus Criteria (Pancreatic IPMN)Gastric Cancer TNM Staging (AJCC 8th)Gastric Emptying Scintigraphy Interpretation Glasgow-Blatchford Score (GBS)H. pylori Eradication Confirmation Algorithm Harmless Acute Pancreatitis Score (HAPS)Harvey-Bradshaw (HBI) to CDAI Conversion Harvey-Bradshaw Index (HBI)IBD Steroid Response Predictor (Oxford)IBS Rome IV Diagnostic Criteria IBS Symptom Severity Score (IBS-SSS)Integrated Relaxation Pressure (IRP) Interpreter JNET Classification (NBI Colonoscopy)Kudo Pit Pattern Classification Lichtiger Index (Modified Truelove & Witts)Los Angeles (LA) Classification (GORD)Lynch Syndrome Risk — Revised Bethesda Guidelines Lyon Consensus pH-Impedance Criteria (GORD)Lémann Index (Crohn's Digestive Damage)M-ANNHEIM Classification (Chronic Pancreatitis)MUST (Malnutrition Universal Screening Tool)Magnetic Resonance Index of Activity (MaRIA)Marsh Classification (Celiac Histopathology)Mayo Endoscopic Subscore (MES)Mayo Score (Ulcerative Colitis)Mirizzi Syndrome Classification (Csendes)Modified CT Severity Index (MCTSI)Montreal Classification (Crohn's Disease)Montreal Classification (Ulcerative Colitis)NICE Classification (NBI Polyp Lexicon)NOBLADS Score (Lower GI Bleeding)NRS-2002 (Nutritional Risk Screening)NSAID GI Risk Stratification (ACG/AGA)Nancy Histopathology Index (UC)Nutritional Risk Index (NRI)OLGA / OLGIM Staging (Gastric Gastritis)Oakland Score (Lower GI Bleeding)Oesophageal Cancer TNM Staging (AJCC 8th)Oxford Acute Severe Colitis Criteria (Travis)PREDICT Barrett's Risk Score Paris Classification (GI Lesion Morphology)Partial Mayo Score (UC)Prague C&M Classification (Barrett's)Ranson Criteria Robarts Histopathology Index (RHI)Rockall Score (Acute UGIB)Rutgeerts Score (Post-op Crohn's)SCCAI (Simple Clinical Colitis Activity Index)SIBO Breath Test Interpreter (Glucose/Lactulose)Serrated Lesion Classification (WHO 2019)Short Bowel Syndrome Classification (ESPEN)Siewert Classification (OGJ Tumours)Simple Endoscopic Score for Crohn's Disease (SES-CD)Strate Score (Diverticular Bleed)TPMT / NUDT15 Phenotype-to-Dose Adjustment Thiopurine Metabolite Interpreter Tokyo Guidelines 2018 (Cholangitis Severity)Tokyo Guidelines 2018 (Cholecystitis Severity)Truelove & Witts Criteria UCEIS (UC Endoscopic Index of Severity)Vienna Classification (Crohn's)Wexner (Cleveland Clinic) Constipation Score Wexner Faecal Incontinence Score (CCFIS)Zar Score (CDI Severity Predictor)

Glasgow-Blatchford Score

Glasgow-Blatchford Score: Validated tool for pre-endoscopic triage of suspected UGI bleeding. Score of 0 identifies patients at very low risk for intervention.

BUN (mmol/L)

Hemoglobin (g/dL) — Male

Systolic BP (mmHg)

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Pre-endoscopic risk stratification of patients with suspected acute upper gastrointestinal bleeding (UGIB)

To identify "low-risk" patients safe for early discharge from the Emergency Department (ED)

Predicting the need for clinical intervention (blood transfusion, endoscopy, or surgery)

Timing

The GBS should be calculated at the point of first contact in the ED. It relies purely on clinical data (SBP, HR, history, melena/syncope) and routine labs (Haemoglobin, BUN).

Exclusion Criteria

Variceal Bleeding Suspected — while GBS is used for all UGIB, patients with known cirrhosis/varices require higher level care regardless of score

Lower GI bleeding (haematochezia without syncope/shock) — GBS is not validated for colonic sources

Section 2

Formula & Logic

Scoring Components (0–23 points)

BUN: Higher levels reflect upper GI blood digestion/absorption.

Haemoglobin: The most direct marker of absolute loss.

Systolic BP: Physiological marker of shock.

Other Features: Presence of melena, syncope, hepatic disease, or heart failure.

The Discharge Threshold

Score 0–1	매우 Low Risk (can consider outpatient management)
Score ≥ 2	High Risk (requires admission and endoscopy)

A Note on the BUN

A high BUN in the setting of normal Creatinine (high BUN/Cr ratio) is a hallmark of upper GI bleeding, as blood protein is converted to urea in the gut.

Section 3

Pearls/Pitfalls

GBS vs. AIMS65 vs. Rockall

In numerous head-to-head trials (e.g., Stanley et al., 2017), GBS proved superior to all other scores for identifying patients who did NOT require intervention. While AIMS65 is better at predicting *mortality*, GBS is the gold standard for *triage deciding who can go home*.

Clinical Pearls

The sensitivity of GBS 0–1 for "no need for intervention" is > 99%

GBS does NOT require endoscopy findings, making it ideal for ED-directed care pathways

A pulse > 100 bpm is weighed significantly in the model (reflecting occult compensation for volume loss)

Section 4

Next Steps

Management Action

GBS ≤ 1: Safe for early discharge with urgent outpatient endoscopy (within 24–48 hours) if patient is stable.

GBS ≥ 2: Hospitalize; Start IV PPI; Perform diagnostic endoscopy.

GBS ≥ 7: High probability of needing endoscopic intervention or blood transfusion.

Complementary Scoring

AIMS65 Score (Mortality)

Rockall Score (Post-endoscopy)

Shock Index (HR/SBP)

Section 5

Evidence Appraisal

The Original Score

A risk score to predict need for treatment for upper-gastrointestinal haemorrhage.

Blatchford O et al. • Lancet. 2000;356(9238):1318-21. The foundational paper establishing the weightings.

View Source

The Gold Standard Validation

Comparison of risk scoring systems for upper gastrointestinal bleeding: international multicentre prospective study.

Stanley AJ et al. • BMJ. 2017;356:i6432. Definitive proof of GBS superiority for clinical triage.

View Source

Section 6

Literature

The Glasgow Group

Developed in Glasgow, Scotland, by Oliver Blatchford and colleagues. The goal was to remove the reliance on endoscopy for initial safety decisions, which was a bottleneck in high-volume public hospitals.

Last Comprehensive Review: 2026

Related Gastroenterology Tools

AIMS65 Score

Forrest Classification

Rockall Score

Ranson Criteria

BISAP Score

Harvey-Bradshaw Index

Crohn's Disease Activity Index

Mayo Score

Truelove & Witts Criteria

Adenoma Detection Rate

Have feedback about this calculator?Let us know.

Glasgow-Blatchford Score

Glasgow-Blatchford Score: Validated tool for pre-endoscopic triage of suspected UGI bleeding. Score of 0 identifies patients at very low risk for intervention.

BUN (mmol/L)

Hemoglobin (g/dL) — Male

Systolic BP (mmHg)

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Pre-endoscopic risk stratification of patients with suspected acute upper gastrointestinal bleeding (UGIB)

To identify "low-risk" patients safe for early discharge from the Emergency Department (ED)

Predicting the need for clinical intervention (blood transfusion, endoscopy, or surgery)

Timing

The GBS should be calculated at the point of first contact in the ED. It relies purely on clinical data (SBP, HR, history, melena/syncope) and routine labs (Haemoglobin, BUN).

Exclusion Criteria

Variceal Bleeding Suspected — while GBS is used for all UGIB, patients with known cirrhosis/varices require higher level care regardless of score

Lower GI bleeding (haematochezia without syncope/shock) — GBS is not validated for colonic sources

Section 2

Formula & Logic

Scoring Components (0–23 points)

BUN: Higher levels reflect upper GI blood digestion/absorption.

Haemoglobin: The most direct marker of absolute loss.

Systolic BP: Physiological marker of shock.

Other Features: Presence of melena, syncope, hepatic disease, or heart failure.

The Discharge Threshold

Score 0–1	매우 Low Risk (can consider outpatient management)
Score ≥ 2	High Risk (requires admission and endoscopy)

A Note on the BUN

A high BUN in the setting of normal Creatinine (high BUN/Cr ratio) is a hallmark of upper GI bleeding, as blood protein is converted to urea in the gut.

Section 3

Pearls/Pitfalls

GBS vs. AIMS65 vs. Rockall

Clinical Pearls

The sensitivity of GBS 0–1 for "no need for intervention" is > 99%

GBS does NOT require endoscopy findings, making it ideal for ED-directed care pathways

A pulse > 100 bpm is weighed significantly in the model (reflecting occult compensation for volume loss)

Section 4

Next Steps

Management Action

GBS ≤ 1: Safe for early discharge with urgent outpatient endoscopy (within 24–48 hours) if patient is stable.

GBS ≥ 2: Hospitalize; Start IV PPI; Perform diagnostic endoscopy.

GBS ≥ 7: High probability of needing endoscopic intervention or blood transfusion.

Complementary Scoring

AIMS65 Score (Mortality)

Rockall Score (Post-endoscopy)

Shock Index (HR/SBP)

Section 5

Evidence Appraisal

The Original Score

A risk score to predict need for treatment for upper-gastrointestinal haemorrhage.

Blatchford O et al. • Lancet. 2000;356(9238):1318-21. The foundational paper establishing the weightings.

View Source

The Gold Standard Validation

Comparison of risk scoring systems for upper gastrointestinal bleeding: international multicentre prospective study.

Stanley AJ et al. • BMJ. 2017;356:i6432. Definitive proof of GBS superiority for clinical triage.

View Source

Section 6

Literature

The Glasgow Group

Last Comprehensive Review: 2026

Related Gastroenterology Tools

AIMS65 Score

Forrest Classification

Rockall Score

Ranson Criteria

BISAP Score

Harvey-Bradshaw Index

Crohn's Disease Activity Index

Mayo Score

Truelove & Witts Criteria

Adenoma Detection Rate

Have feedback about this calculator?Let us know.