1,329 calculators and references across 60 specialties, with formula confidence shown up front.
: Explanation and Clinical Context This page implements a configurable logistic risk model intended to predict the probability of heart failure (HF) hospitalization using readily available clinical variables (age, NYHA class, prior HF admission, NT-proBNP, eGFR, systolic blood pressure, heart rate, hemoglobin). The calculator itself does not assume or embed any particular published coefficients; instead it accepts a
Atrial Fibrillation Type -- choose -- Paroxysmal Persistent Long-standing persistent eGFR (mL/min/1.73m2) Left Atrial Diameter (mm) Left Ventricular Ejection Fraction (%) Number of Prior AF Ablations : Explanation and Clinical Context This calculator integrates two validated models—APPLE and SUCCESS—to predict the likelihood of atrial fibrillation (AF) recurrence after catheter ablation. The APPLE score assigns one p
CathLab Shock (CardShock-based) Score: Explanation and clinical context The calculator above implements the CardShock risk score items (age, altered mental status/confusion at presentation, prior MI or CABG, ACS aetiology, LVEF <40%, arterial lactate category, and eGFR category) using the original CardShock thresholds and point allocations. The CardShock score was developed in a prospective multicentre cohort to pred
Central Aortic Pressure Index (CAPI): Explanation and Clinical Context The Central Aortic Pressure Index (CAPI) represents the ratio of central aortic pressure to peripheral systolic pressure, reflecting the impact of arterial wave reflections and aortic stiffness on central hemodynamics. It is calculated using peripheral systolic pressure (PSP) and augmentation index (AIx), which represents the contribution of refle
CHA₂DS₂-VASc Score: Explanation and Clinical Context The CHA₂DS₂-VASc Score is a validated clinical risk stratification tool used to estimate the annual risk of ischemic stroke in patients with atrial fibrillation (AF), particularly non-valvular AF. It refines the earlier CHADS₂ Score by incorporating additional risk factors—vascular disease, age 65–74 years, and female sex—to improve sensitivity in identifying patie
Comprehensive Explanation: The CHA2DS2-VASc-ACS Score is an adaptation of the original CHA2DS2-VASc risk model—initially used for atrial fibrillation—to evaluate cardiovascular and cerebrovascular risk in patients with acute coronary syndrome (ACS) or post-myocardial infarction (MI). Higher scores indicate greater burden of systemic vascular disease and increased likelihood of recurrent events or mortality after MI.
Follow-up horizon (years) Chagas Disease Cardiac Progression Index (CPI): Explanation and Clinical Context This calculator estimates the risk that a patient with Chagas disease will progress to clinically manifest cardiomyopathy over a specified time horizon using pooled annual incidence rates. For individuals with the indeterminate chronic form (no baseline cardiac injury on ECG/echocardiography), the pooled annual
— explanation and clinical context This page provides a prototype, point-based risk stratification tool informed by variables central to pulmonary artery pressure-guided heart failure management (age, NYHA class, prior HF hospitalization, mean pulmonary artery pressure, LVEF, renal function, and NT-proBNP). The CHAMPION randomized trial evaluated the CardioMEMS pulmonary artery pressure monitoring system and demonstr
Charlson Comorbidity Index Explanation and Clinical Context Charlson Comorbidity Index is a widely used clinical scoring system that quantifies the burden of chronic disease and predicts the risk of mortality by assigning weights to specific comorbid conditions. It provides a structured method to estimate long term prognosis and helps clinicians stratify risk especially in hospitalized patients or those undergoing ma
CHARM Renal Subgroup Score: Explanation and Clinical Context The CHARM Renal Subgroup Score was developed from the CHARM trials to assess prognosis in heart failure patients with renal dysfunction. It incorporates age, renal function (serum creatinine), NYHA class, and comorbidities such as diabetes, hypertension, and prior myocardial infarction. Higher scores are associated with increased risk of cardiovascular deat
CHARM prognostic model (primary endpoint: cardiovascular death or heart-failure hospitalization — 2-year risk) The CHARM prognostic models were developed using 7,599 patients enrolled in the CHARM programme and identify 21 independent predictors of outcome across the spectrum of left ventricular systolic function. The model forms a linear risk score by summing each predictor multiplied by its coefficient (log hazard)
CHD-Specific NYHA-like Class (Ross Classification): Explanation and Clinical Context The Ross Classification is a pediatric modification of the NYHA functional classification for patients with congenital heart disease (CHD). It stratifies patients based on symptom severity and limitation of physical activity. Class I indicates asymptomatic status, Class II denotes mild symptoms with ordinary activity, Class III refle
Child Pugh Liver Cirrhosis Score Explanation and Clinical Context The Child Pugh Score is a clinical tool used to assess the severity and prognosis of chronic liver disease particularly cirrhosis. It evaluates five key clinical and laboratory parameters which reflect liver synthetic function portal hypertension and systemic complications of liver dysfunction. These parameters are serum bilirubin serum albumin interna
Child–Turcotte–Pugh (CTP / Child–Pugh) score — explanation and references The Child–Pugh score is a 5-item clinical scoring system originally developed to estimate prognosis in chronic liver disease and cirrhosis and to guide surgical risk assessment. Each of five parameters (total bilirubin, serum albumin, coagulation — expressed as INR or PT prolongation — ascites, and hepatic encephalopathy) is scored 1–3 points a
CHOP-CHD Neurodevelopmental Risk Index: Explanation and Clinical Context The CHOP-CHD Neurodevelopmental Risk Index is a validated tool designed to estimate the probability of neurodevelopmental impairment in children following congenital heart disease (CHD) surgery. It incorporates key clinical and perioperative variables, including gestational age, birth weight, presence of single ventricle physiology, duration of
CHOP/Anthracycline Cumulative Dose Score: Explanation and Clinical Context The CHOP/Anthracycline Cumulative Dose Score estimates the risk of anthracycline-induced cardiotoxicity by calculating the total doxorubicin-equivalent dose from different anthracycline drugs, including doxorubicin, daunorubicin, and epirubicin. Conversion factors are applied to account for differences in cardiotoxic potential: daunorubicin ×
Known hypothyroidism -- select -- Yes No Symptom onset > 2 weeks before index PE diagnosis -- select -- Yes No Right ventricular dysfunction on CT or echocardiography (at index PE) -- select -- Yes No Known diabetes mellitus -- select -- Yes No Thrombolytic therapy or embolectomy for the acute PE event -- select -- Yes No CTEPH Prediction Score: Explanation and Clinical Context Chronic thromboembolic pulmonary hypert
The audited source currently returns an empty page. This catalog entry is retained for coverage and monitoring, but no clinical content or calculation is asserted.
The audited source currently returns an empty page. This catalog entry is retained for coverage and monitoring, but no clinical content or calculation is asserted.
Chronotropic Index: Explanation and Clinical Context Chronotropic Index is a physiologic measure that reflects the ability of the heart to increase its rate during physical exertion. It evaluates the relationship between the actual heart rate achieved during exercise and the predicted heart rate reserve. This parameter is commonly used in exercise stress testing to assess whether the chronotropic response is appropri
Chronotropic Index: Explanation and Clinical Context Chronotropic Index is a physiologic measure that reflects the ability of the heart to increase its rate during physical exertion. It evaluates the relationship between the actual heart rate achieved during exercise and the predicted heart rate reserve. This parameter is commonly used in exercise stress testing to assess whether the chronotropic response is appropri
CHSS Mortality Score: Explanation and Clinical Context The CHSS Mortality Score is a clinical tool used to estimate the risk of mortality in patients with congenital heart disease. It incorporates various physiological parameters to provide a comprehensive risk assessment. The score assists clinicians in making informed decisions regarding patient management and treatment strategies.
CK-MB Elevation Index (Post-CABG Infarction): Explanation and Clinical Context The CK-MB Elevation Index is calculated by dividing the peak postoperative CK-MB value by the laboratory's upper reference limit (URL). It is used to estimate the likelihood of perioperative myocardial infarction following coronary artery bypass graft (CABG) surgery. A CK-MB index <3 is generally associated with low risk, 3–5 with intermed
Explanation and Clinical Context The CKD EPI GFR equation provides an estimation of glomerular filtration rate which is a fundamental indicator of kidney function. This equation improves accuracy especially in higher GFR ranges and reduces the systematic bias found in previous formulas. The calculation incorporates serum creatinine age sex and race to generate a clinically relevant estimate of renal function. An esti
CL Score (CTO Lesion Complexity): Explanation and Clinical Context The CL Score (CTO Lesion Complexity Score) is an angiographic grading system used to predict the procedural success rate of percutaneous coronary intervention (PCI) in chronic total occlusion (CTO) lesions. It is derived from the validated J-CTO score, first introduced by Morino et al. in 2011, and evaluates five anatomical features that influence the
: Explanation and Clinical Context This tool estimates the risk of developing heart failure following anthracycline chemotherapy based on key clinical factors. It incorporates the cumulative dose of doxorubicin, patient age, and the presence of hypertension, diabetes mellitus, and smoking history. A higher risk score indicates a greater likelihood of cardiotoxicity, guiding clinicians in monitoring and preventive str
Cleveland Clinic Risk Model: Explanation and Clinical Context The Cleveland Clinic Risk Model is a validated tool used to estimate the risk of major adverse cardiac events or mortality in patients undergoing cardiac surgery. It incorporates patient-specific variables including age, sex, history of heart failure, serum creatinine, and urgency of surgery to calculate a logistic regression-based probability. The model p
Clinical Frailty Scale (CFS): Explanation and Clinical Context The Clinical Frailty Scale (CFS) is a validated 9-point scale developed to assess the overall level of fitness or frailty in older adults. It ranges from 1 (very fit) to 9 (terminally ill) and incorporates physical activity, dependence on others, and comorbidity status. It is used in clinical settings to predict outcomes such as mortality, hospitalization
Explanation and Clinical Context This tool helps clinicians judge when clopidogrel monotherapy is appropriate after acute coronary syndromes by integrating key constructs from the twenty twenty five American Heart Association guideline on acute coronary syndromes. The guideline emphasizes that dual antiplatelet therapy with aspirin and a P2Y12 inhibitor remains the default approach for at least one year in patients w
Inputs for Systolic Dyssynchrony Index (SDI; time-to-peak based) CMR Feature Tracking Dyssynchrony Index: Explanation and Clinical Context Cardiovascular magnetic resonance feature tracking (CMR-FT) enables derivation of strain-time curves from standard SSFP cine images without additional tagging sequences. Mechanical dyssynchrony can be quantified in two complementary ways. First, a systolic dyssynchrony index (SDI)
CMR Late Enhancement Pericarditis Index (LEPI): Explanation and Clinical Context The CMR LEPI is a quantitative tool developed to assess the severity and risk stratification in patients with acute or chronic pericarditis using cardiac magnetic resonance imaging. It integrates three key parameters: pericardial late gadolinium enhancement (LGE) score, pericardial thickness measured on imaging, and pericardial edema det
COACH Score: Explanation and Clinical Context The COACH Score is a validated risk stratification tool for patients with chronic heart failure, predicting mortality and risk of hospital readmission. It incorporates age, sex, NYHA functional class, left ventricular ejection fraction, systolic blood pressure, serum creatinine, and prior heart failure hospitalization, with weighted points derived from the COACH study. Th
COAPT Score (MitraClip Responder Model): Explanation and Clinical Context The COAPT Score is a simple point-based model derived from the COAPT randomized trial to stratify the 2-year risk of all-cause death and/or heart failure hospitalization in patients with heart failure and significant secondary mitral regurgitation despite guideline-directed medical therapy. It assigns weighted points to clinical and echocardiog
Cockcroft Gault creatinine clearance estimation Explanation and clinical context The Cockcroft Gault equation provides an estimate of creatinine clearance in milliliters per minute using patient age weight serum creatinine and sex. The formula is CrCl equals open parentheses 140 minus age close parentheses times weight divided by open parentheses 72 times serum creatinine close parentheses. For female patients multip
Collapsibility Index and Distensibility Index: Explanation and Clinical Context The measurement of the inferior vena cava provides a noninvasive method to estimate right atrial pressure and to assess intravascular volume status. The collapsibility index compares the maximum diameter of the inferior vena cava during expiration with the minimum diameter during inspiration. A greater degree of collapse often reflects lo
Player age (years) Projectile speed (mph) (enter best estimate; 40 mph is peak hazard in experimental models) Projectile type Standard/official ball or puckReduced-impact safety baseball (T-ball/soft core)Other/unknown NOCSAE-certified chest protection worn? No/UnknownYes (NOCSAE commotio cordis standard) Commotio Cordis Risk Model (Sport-Specific): Explanation and Clinical Context This calculator provides an evidenc
Community ASCVD Screening Yield Calculator: Explanation and Clinical Context This tool estimates the yield and population-level impact of community cardiovascular risk screening followed by statin therapy for primary prevention. Inputs include: average 10-year ASCVD risk among screen-positive individuals, expected LDL-C reduction (mmol/L) with the chosen regimen, treatment uptake, adherence, screen-positivity, and sc
Community Cholesterol Program Impact: Explanation and Clinical Context This calculator estimates the population-level impact of a community cholesterol screening program targeting high-risk individuals. The Absolute Risk Reduction (ARR) is derived from the average 10-year ASCVD risk among screen-positive individuals multiplied by the relative risk reduction (RRR) achievable with statin therapy. The Number Needed to T
The audited source currently returns an empty page. This catalog entry is retained for coverage and monitoring, but no clinical content or calculation is asserted.
COMPASS Trial Polyvascular Risk Score — Explanation and clinical context This tool implements the COMPASS trial subgroup framework by counting four high-risk features associated with greater absolute benefit from combined rivaroxaban 2.5 mg twice daily plus aspirin versus aspirin alone: polyvascular disease (≥2 vascular beds affected), renal dysfunction (eGFR < 60 mL/min/1.73m²), a history of heart failure, and diabe
COMPERA 2.0 Risk Model: Explanation and Clinical Context The COMPERA 2.0 Risk Model is an updated four-strata prognostic system for patients with pulmonary arterial hypertension (PAH), derived from the large COMPERA registry. It refines the previous three-strata model by dividing the intermediate group into two categories: intermediate-low and intermediate-high, enhancing clinical decision-making and treatment target
Confusion Matrix Diagnostic Metrics Explanation and Clinical Context Confusion matrix based diagnostic performance evaluation is a core approach in clinical research and medical device development because it quantifies how well a diagnostic modality identifies disease. A confusion matrix contains four elements namely true positive false positive false negative and true negative which represent the fundamental outcome
Congestive Hepatic Fibrosis Score (CHFS): explanation and clinical context The CHFS is a histology-based grading system that stages fibrosis patterns seen in congestive hepatopathy on liver biopsy — it ranges from 0 (no fibrosis) through 4 (cirrhosis), with intermediate grades that distinguish centrizonal-limited fibrosis (stage 1), combined centrizonal and portal patterns with differing zone predominance (2A and 2B)
Constriction Probability Score (Echo-based): Explanation and Clinical Context The Constriction Probability Score (Echo-based) is a diagnostic tool designed to assess the likelihood of constrictive pericarditis using echocardiographic parameters. This score incorporates key measurements such as Left Atrial Volume Index (LAVI), Right Atrial Volume Index (RAVI), Tricuspid Annular Plane Systolic Excursion (TAPSE), and Tr
CONUT Score (Controlling Nutritional Status): Explanation and Clinical Context CONUT Score is a validated nutritional screening tool that estimates malnutrition in hospitalized patients using three laboratory parameters: serum albumin, total lymphocyte count, and total cholesterol. Albumin reflects protein reserves, lymphocyte count reflects immune function, and cholesterol reflects caloric depletion. The total CONUT
Conventional Troponin 0 to 3 to 6 Hour Diagnostic Algorithm Explanation and Clinical Context This tool is designed for patients with suspected acute coronary syndrome in whom a conventional cardiac troponin assay is used rather than a high sensitivity assay. According to the twenty twenty five acute coronary syndrome guideline, cardiac troponin is the preferred biomarker for detection of myocardial injury and acute m
COPD GOLD Staging Explanation and Clinical Context Chronic Obstructive Pulmonary Disease is assessed using the Global Initiative for Chronic Obstructive Lung Disease classification which relies on the value of forced expiratory volume in one second expressed as percent predicted. This parameter reflects the degree of airflow limitation and correlates with severity of disease and symptom burden. The GOLD system places
Copeptin–Troponin Composite Model: Explanation and Clinical Context The Copeptin–Troponin Composite Model refers to a dual‑biomarker approach combining measurement of copeptin (a stable surrogate marker of arginine‑vasopressin release) and high‑sensitivity cardiac troponin I (hs‑cTnI) on admission in patients with suspected acute cardiac injury or other cardiocirculatory stress. The rationale is that while troponin i
: Explanation and Clinical Context This tool provides a simplified risk estimate for a composite adverse outcome (including mortality, major complications such as moderate‑severe paravalvular leak, pacemaker implantation, or valve thrombosis) at 1 year after transcatheter aortic valve replacement (TAVR) using either a self‑expandable device (e.g., CoreValve) or a balloon‑expandable device (e.g., Sapien). The model in
Cormier Score for Rheumatic Mitral Stenosis: Explanation and Clinical Context The Cormier Score is an echocardiographic scoring system used to evaluate the suitability of patients with rheumatic mitral stenosis for percutaneous balloon mitral valvuloplasty (PBMV). It assesses anterior mitral leaflet mobility, presence of leaflet calcification, and severity of subvalvular involvement. Patients are stratified into thre
Cornell Voltage–Duration Product (CVDP): Explanation and Clinical Context The Cornell Voltage–Duration Product (CVDP) is a refined electrocardiographic index developed to improve the detection of left ventricular hypertrophy (LVH) by integrating both voltage magnitude and QRS duration. It was proposed by Molloy et al. (Circulation, 1992) based on data from the Cornell and Framingham studies. Formula: CVDP = (R in aVL
The audited source currently returns an empty page. This catalog entry is retained for coverage and monitoring, but no clinical content or calculation is asserted.
Coronary Artery Calcium (CAC) Percentile Ranking: Explanation and Clinical Context CAC percentile ranking provides an age- and sex-specific comparison of an individual's coronary artery calcium score to a reference population, as defined in the Multi-Ethnic Study of Atherosclerosis (MESA). It helps to stratify atherosclerotic cardiovascular disease (ASCVD) risk beyond traditional risk factors. A higher percentile ind
Coronary Artery Volume Score (CAVS): Explanation and Clinical Context The Coronary Artery Volume Score quantifies the total volume of the main coronary arteries (Left Main, Left Anterior Descending, Left Circumflex, Right Coronary Artery) as measured on coronary computed tomography angiography (CCTA). It is used to assess the overall burden of atherosclerosis within the coronary circulation. Higher values indicate gr
Date of Birth Gestational Age at Birth Weeks Current Date Corrected Age for Preterm Infants Explanation and Clinical Context Corrected age also known as adjusted age is used to evaluate growth and developmental progression in infants born before term. It reflects the age the infant would be if the pregnancy had reached forty weeks and helps provide a more accurate assessment of neurologic development physical growth
: Explanation and Clinical Context Metabolic acidosis represents a pathophysiologic condition characterized by a decrease in plasma bicarbonate concentration and a reduction in blood pH. Base excess is a key variable used in clinical practice to quantify the magnitude of metabolic acidosis and estimate the bicarbonate requirement needed for partial correction. The standard bicarbonate deficit formula incorporates bod
Correlation Coefficient Explanation and Clinical Context The correlation coefficient r is a numerical index that quantifies the strength and direction of the linear relationship between two continuous variables. A positive value indicates a direct linear association while a negative value reflects an inverse linear association. The magnitude of r reflects the strength of the relationship. Values close to one or minus
Cost-Effectiveness of Statin Therapy by Age/Risk Model: Explanation and Clinical Context This calculator implements a transparent, adjustable cost-effectiveness framework for primary-prevention statin therapy anchored to a patient’s 10-year ASCVD risk and therapy intensity. It estimates absolute risk reduction as baseline risk × RRR and converts events prevented into QALYs. Treatment disutility and excess diabetes ri
CPET Composite Risk Index for HFrEF & HFpEF: Explanation and Clinical Context The CPET Composite Risk Index integrates key cardiopulmonary exercise testing (CPET) variables to stratify risk in patients with heart failure, both HFrEF and HFpEF. The index combines peak oxygen consumption (Peak VO₂), ventilatory efficiency (VE/VCO₂ slope), heart rate recovery at 1 minute (HRR), and the VE/MVV ratio. Peak VO₂ reflects ov
CPET Prognostic Score (HFpEF): Explanation and Clinical Context Cardiopulmonary exercise testing (CPET) is a valuable tool in assessing prognosis in patients with heart failure with preserved ejection fraction (HFpEF). The CPET Prognostic Score incorporates key parameters such as peak VO₂, VE/VCO₂ slope, and peak exercise oxygen pulse to stratify risk in this patient population.