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All 206CHA₂DS₂-VAScCardiologyeGFRNephrology & ElectrolytesMELD-NaHepatology & GIWells PECardiologyCURB-65Pulmonary & Critical CareHEARTCardiologyAnion gapNephrology & ElectrolytesCorrected CaNephrology & ElectrolytesQTcCardiologyHAS-BLEDCardiologyChild-PughHepatology & GIGlasgow-BlatchfordHepatology & GICrClNephrology & ElectrolytesBMIGeneral & AnthropometricsGCSPulmonary & Critical CarePHQ-9Psychiatry & Substance Use
By specialty
Cardiology
- Age-Adjusted D-dimer Cutoff for Pulmonary Embolism
- ASCVD 10-Year Risk (2013 Pooled Cohort Equations)
- ATRIA Bleeding Risk Score
- Calculated LDL Cholesterol (Friedewald and Sampson/NIH)
- Cardiac Output by the Fick Principle
- CHA₂DS₂-VASc Score for Atrial Fibrillation Stroke Risk
- CHADS-65 Algorithm (Canadian Cardiovascular Society) for AF Anticoagulation
- CHADS₂ Score for Atrial Fibrillation Stroke Risk
- Corrected QT Interval (QTc)
- Duke Treadmill Score
- EDACS (Emergency Department Assessment of Chest Pain Score)
- Framingham Risk Score (ATP III, 10-Year Hard CHD)
- GRACE Score for In-Hospital Mortality in ACS
- H₂FPEF Score for HFpEF Probability
- HAS-BLED Score for Major Bleeding Risk in Atrial Fibrillation
- HEART Score for Major Cardiac Events in Chest Pain
- HEMORR₂HAGES Bleeding Risk Score
- Hestia Criteria for Outpatient Pulmonary Embolism Treatment
- Mean Arterial Pressure (MAP)
- Non-HDL Cholesterol
- ORBIT Bleeding Risk Score for Atrial Fibrillation
- PERC Rule for Pulmonary Embolism
- Pulmonary Embolism Severity Index (PESI)
- Revised Geneva Score for Pulmonary Embolism
- Sgarbossa Criteria (Original and Smith-Modified) for MI in LBBB
- Shock Index
- Simplified Pulmonary Embolism Severity Index (sPESI)
- TIMI Risk Score for STEMI
- TIMI Risk Score for UA/NSTEMI
- Wells Score for Deep Vein Thrombosis
- Wells Score for Pulmonary Embolism
- YEARS Algorithm for Pulmonary Embolism
Nephrology & Electrolytes
- Albumin-Corrected Delta Gap
- Albumin-Corrected Delta Ratio
- Bedside Schwartz eGFR (Pediatric)
- Bicarbonate Deficit
- BUN:Creatinine Ratio (Urea:Creatinine)
- Calculated Serum Osmolality
- Corrected Calcium for Albumin
- Corrected Sodium in Hyperglycemia
- Creatinine Clearance (Cockcroft-Gault)
- Delta Gap and Delta Ratio
- eGFR (CKD-EPI 2021 Creatinine–Cystatin C)
- eGFR (CKD-EPI 2021, race-free)
- eGFR (MDRD Study equation)
- Expected HCO₃ in Respiratory Acidosis / Alkalosis
- Expected pCO₂ in Metabolic Alkalosis
- Fractional Excretion of Sodium (FENa)
- Fractional Excretion of Urea (FEUrea)
- Free Water Deficit in Hypernatremia
- Kidney Failure Risk Equation (KFRE, 4-variable)
- Serum Anion Gap (with Albumin Correction)
- Serum Osmolal Gap
- Sodium Change per Litre of Infusate (Adrogué–Madias)
- Transtubular Potassium Gradient (TTKG)
- Urine Anion Gap
- Urine Osmolal Gap
- Urine Protein:Creatinine Ratio (Estimated 24-h Proteinuria)
- Winters' Formula (Expected pCO₂ in Metabolic Acidosis)
Hepatology & GI
- ABIC Score (Alcoholic Hepatitis)
- AIMS65 Score for Upper GI Bleeding
- ALBI Grade (Albumin-Bilirubin)
- Alvarado Score for Acute Appendicitis
- APRI (AST to Platelet Ratio Index)
- BISAP Score for Acute Pancreatitis Mortality
- Boston Bowel Preparation Scale (BBPS)
- Child-Pugh Score for Cirrhosis
- Crohn's Disease Activity Index (CDAI)
- CT Severity Index (Balthazar) for Acute Pancreatitis
- FIB-4 Index for Liver Fibrosis
- Glasgow Alcoholic Hepatitis Score (GAHS)
- Glasgow-Blatchford Bleeding Score (GBS)
- Glasgow-Imrie Criteria for Acute Pancreatitis Severity
- Harvey-Bradshaw Index (Crohn's Disease)
- King's College Criteria for Liver Transplant in Acute Liver Failure
- Lille Model (Day 7, Alcoholic Hepatitis)
- Maddrey Discriminant Function (Alcoholic Hepatitis)
- MELD 3.0 (Kim 2021, OPTN 2023)
- MELD Score (original UNOS MELD)
- MELD-Na Score (UNOS/OPTN 2016)
- Milan Criteria for Liver Transplantation in Hepatocellular Carcinoma
- Modified Marshall Score for Organ Failure (Acute Pancreatitis)
- NAFLD Fibrosis Score
- Oakland Score for Lower GI Bleeding
- Partial Mayo Score (Ulcerative Colitis)
- Ranson Criteria for Acute Pancreatitis
- Rockall Score (Complete, Post-endoscopy)
- Rockall Score (Pre-endoscopy / Clinical)
- Serum-Ascites Albumin Gradient (SAAG)
- Stool Osmotic Gap
- Truelove and Witts Criteria (Ulcerative Colitis Severity)
Pulmonary & Critical Care
- Alveolar–Arterial (A–a) O₂ Gradient
- APACHE II Score
- ARDSNet Tidal Volume (Predicted Body Weight)
- BODE Index for COPD Survival
- CRB-65 Score for Pneumonia (no labs)
- CURB-65 Score for Pneumonia Severity
- Glasgow Coma Scale (GCS)
- Light's Criteria for Pleural Effusion
- NEWS2 (National Early Warning Score 2)
- Oxygenation Index (OI)
- PaO₂/FiO₂ (P/F) Ratio with Berlin ARDS Severity
- Pneumonia Severity Index (PSI / PORT Score)
- qSOFA (Quick SOFA) Score for Sepsis
- ROX Index for High-Flow Nasal Cannula
- SIRS Criteria (Systemic Inflammatory Response Syndrome)
- SOFA Score (Sequential Organ Failure Assessment)
- STOP-Bang Questionnaire for Obstructive Sleep Apnea
Emergency & Trauma
- ABC Score for Massive Transfusion
- Canadian C-Spine Rule
- Canadian CT Head Rule
- Canadian Syncope Risk Score (CSRS)
- NEXUS Criteria for C-Spine Imaging
- Ottawa Ankle Rules
- Ottawa Knee Rule
- Ottawa Subarachnoid Hemorrhage (SAH) Rule
- Parkland Formula for Burn Resuscitation
- PECARN Pediatric Head Injury Rule (< 2 years)
- PECARN Pediatric Head Injury Rule (≥ 2 years)
- Revised Trauma Score (RTS)
- Rule of Nines (Adult Burn TBSA)
- San Francisco Syncope Rule
Pediatrics & Obstetrics
- APGAR Score (Newborn Assessment)
- Bishop Score (Cervical Ripeness for Induction)
- Brighton Paediatric Early Warning Score (PEWS)
- Estimated Conception Date from LMP
- Gestational Age from Due Date
- IVF Due Date (Embryo Transfer Date)
- Kocher Criteria for Septic Arthritis of the Hip (Children)
- Maintenance IV Fluids (Holliday-Segar 4-2-1 Rule)
- PECARN Febrile Infant Rule (29–60 days)
- Pediatric Appendicitis Score (PAS, Samuel)
- Pediatric Endotracheal Tube Size and Depth
- Pediatric Glasgow Coma Scale
- Pediatric Weight Estimation by Age (APLS)
- PRAM (Pediatric Respiratory Assessment Measure) for Asthma
- Pregnancy Due Date Calculator (Naegele's Rule from LMP)
- Rochester Criteria (Low-Risk Febrile Infant ≤ 60 days)
- Westley Croup Score
Hematology & Oncology
- 4Ts Score for Heparin-Induced Thrombocytopenia
- Absolute Neutrophil Count (ANC)
- ECOG Performance Status ↔ Karnofsky (KPS) Conversion
- HScore for Reactive Hemophagocytic Lymphohistiocytosis (HLH)
- International Prognostic Index (IPI) for Aggressive Lymphoma
- Iron Deficit (Ganzoni Formula)
- ISTH Overt DIC Score
- Khorana Score for Chemotherapy-Associated VTE
- Mentzer Index (Thalassemia Trait vs Iron Deficiency)
- Padua Prediction Score for VTE in Medical Inpatients
- PLASMIC Score for TTP
- Reticulocyte Production Index (Corrected Reticulocyte Count)
- Revised International Prognostic Index (R-IPI) for DLBCL
- Transferrin Saturation (TSAT)
Psychiatry & Substance Use
- Adult ADHD Self-Report Scale (ASRS v1.1) Screener, Part A
- AUDIT Alcohol Use Disorders Identification Test
- AUDIT-C Alcohol Use Screen
- CAGE Questionnaire for Alcohol Use
- CIWA-Ar Alcohol Withdrawal Scale
- COWS Clinical Opiate Withdrawal Scale
- Edinburgh Postnatal Depression Scale (EPDS)
- GAD-7 Generalized Anxiety Disorder Scale
- Hamilton Depression Rating Scale (HAM-D 17-item)
- PHQ-9 Depression Severity (Patient Health Questionnaire-9)
- Primary Care PTSD Screen for DSM-5 (PC-PTSD-5)
General & Anthropometrics
- Adjusted Body Weight (Dosing Weight)
- Body Mass Index (BMI)
- Body Surface Area (Mosteller)
- Charlson Comorbidity Index (CCI)
- Clinical Disease Activity Index (CDAI) for Rheumatoid Arthritis
- DAS28-CRP (Disease Activity Score, 28 joints, CRP) for Rheumatoid Arthritis
- DAS28-ESR (Disease Activity Score, 28 joints, ESR) for Rheumatoid Arthritis
- Harris-Benedict Equation (Revised, Roza & Shizgal 1984)
- Ideal Body Weight (Devine)
- Lean Body Weight (Janmahasatian)
- Mifflin-St Jeor Equation (Resting Energy Expenditure)
- Number Needed to Treat (NNT) / Harm (NNH)
- Pack-Years Smoking History
- Post-Test Probability from Likelihood Ratio (Bayes)
- Sensitivity, Specificity, PPV, NPV from a 2×2 Table
- Simplified Disease Activity Index (SDAI) for Rheumatoid Arthritis
- Target Weight for a Target BMI
- Temperature Conversion (°C ↔ °F)
- Total Body Water (Watson Formula)