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)

Crohn's Disease Activity Index (CDAI)

Crohn's Disease Activity Index (CDAI)

8-variable 7-day diary-based score. Remission = CDAI < 150. For bedside use, consider Harvey-Bradshaw Index (HBI) as the validated same-day surrogate (r = 0.93).

7-Day Diary Values

Total Liquid/Soft Stools (7-day)

Sum of all loose/soft stools across 7 days

0

Total Abdominal Pain Score (7-day)

Daily score 0–3 summed over 7 days (max 21)

0

Total Wellbeing Score (7-day)

Daily score 0–4 summed over 7 days (max 28)

0

Number of Complications

Arthritis, iritis, EN, pyoderma, aphthous ulcers, anal lesion, fistula, fever >37.8°C

0

Antidiarrhoeals Used?

Abdominal Mass

Patient Sex (for Haematocrit Reference)

HCT (%)

42

Current Wt (kg)

70

Standard Wt (kg)

70

Guidelines & Evidence

Verified

Last Review: 2026

When to Use

When to Use

Primary outcome measure in clinical trials for Crohn's disease therapies

To quantify disease activity and assess response/remission in complex IBD cases

To track therapeutic efficacy over a 7-day retrospective window

Patient Population

Adults with established Crohn's disease. Not validated for pediatric use (PCDAI is used instead) or for patients with isolated perianal disease without luminal activity.

When to Use HBI Instead

Routine clinic visits — CDAI requires a 7-day patient diary, making it difficult for real-time triage; the Harvey-Bradshaw Index (HBI) is better for daily practice

Fibrotic strictures — CDAI captures inflammatory activity; obstructive symptoms from fibrosis may skew the score inappropriately

Primary ileal resection — some categories (like stool count) may be elevated due to bile acid malabsorption rather than active Crohn's

Last Comprehensive Review: 2026

Related Gastroenterology Tools

Magnetic Resonance Index of Activity

PREDICT Barrett's Risk Score

Tokyo Guidelines 2018

ASGE Choledocholithiasis Risk Stratification

Harvey-Bradshaw Index

Colorectal Submucosal Invasion

Montreal Classification

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