Clinical library

Every tool, one focused workspace.

1,329 calculators and references across 60 specialties, with formula confidence shown up front.

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PET-CT Uptake Grading Score Calculator

PET-CT Uptake Grading Score: Explanation and Clinical Context The PET-CT Uptake Grading Score is used to quantify the metabolic activity of lesions relative to reference tissues (liver and blood pool) in FDG PET-CT imaging. Grade 0 indicates no significant uptake, Grade 1 indicates low uptake (above blood pool but below liver), Grade 2 indicates moderate uptake (equal to or above liver but less than twice liver SUVme

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PETCO2 at AT Index Calculator

PETCO₂ at AT Index: Explanation and Clinical Context The PETCO₂ at Anaerobic Threshold (AT) Index measures the partial pressure of end-tidal CO₂ at the anaerobic threshold during cardiopulmonary exercise testing (CPET). This index reflects ventilatory efficiency and the balance between CO₂ production and elimination. Lower PETCO₂ at AT (<30 mmHg) indicates inefficient ventilation, often observed in patients with hear

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PETIE Index (PET-based IE Probability) Calculator

PETIE Index: Explanation and Clinical Context The PETIE Index is a clinical tool designed to estimate the probability of infective endocarditis (IE) in patients undergoing 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT). This index incorporates the following parameters: - FDG-PET/CT Findings: A positive FDG-PET/CT result is associated with a higher likelihood of IE, contributing 2

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PFO Closure Risk (RoPE) Score Calculator

PFO Closure Risk (RoPE) Score: Explanation and Clinical Context The RoPE (Risk of Paradoxical Embolism) score is a validated 10-point tool designed for patients with cryptogenic ischemic stroke in whom a patent foramen ovale (PFO) is detected. It estimates how likely the index stroke is causally related to the PFO (rather than incidental) and contextualizes the expected 2-year recurrence risk under medical management

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Pheochromocytoma Perioperative Cardiac Risk Index (P-PCRI) Calculator

Pheochromocytoma Perioperative Cardiac Risk Index (P-PCRI): Explanation and Clinical Context This tool estimates the perioperative risk of significant intraoperative hemodynamic instability during adrenalectomy for pheochromocytoma by integrating preoperative clinical and CT-based predictors. Variables include age, BMI, tumor laterality, tumor shape, MAP score, necrosis, planned surgical technique, CHD status, and pr

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PHQ-9 Depression Score Calculator (for Cardiac Patients)

PHQ-9 Depression Score (for Cardiac Patients): Explanation and Clinical Context The PHQ-9 (Patient Health Questionnaire-9) is a widely used, validated tool to screen and measure the severity of depression, specifically useful in cardiac patients where depression is a known risk factor for worse cardiovascular outcomes. It includes 9 questions reflecting DSM-IV criteria for depression, scored from 0 (Not at all) to 3

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Physical Activity Index (IPAQ) Calculator

International Physical Activity Questionnaire (IPAQ) Short Form: Explanation and Clinical Context The IPAQ Short Form is a validated questionnaire designed to estimate weekly physical activity levels in adults. It captures frequency (days per week) and duration (minutes per day) of walking, moderate, and vigorous activities. The resulting MET-minutes/week provides a standardized measure of total physical activity. Ph

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PIONEER-AF-PCI Bleeding Algorithm Calculator

PIONEER-AF-PCI Bleeding Algorithm: Explanation and Clinical Context The PIONEER-AF-PCI trial randomized patients with nonvalvular atrial fibrillation who underwent PCI with stent placement to one of three antithrombotic strategies and measured clinically significant bleeding at 12 months. The trial found lower rates of clinically significant bleeding in two rivaroxaban-based strategies compared with standard therapy

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Platelet-Lymphocyte Ratio (PLR) Calculator

Platelet–Lymphocyte Ratio (PLR): Explanation and Clinical Context The Platelet–Lymphocyte Ratio (PLR) is a systemic inflammatory marker calculated as the ratio of platelet count to lymphocyte count in peripheral blood. Elevated PLR reflects both an increased platelet count, often associated with pro-thrombotic and inflammatory states, and a relative lymphopenia, indicating impaired immune regulation. PLR has been stu

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PLN Mutation Arrhythmic Risk Model (PLN Risk Calculator)

PLN p.Arg14del arrhythmic risk model — explanation and clinical context This tool implements the primary phenotypic predictors selected in the multivariable PLN p.Arg14del prediction model published by Verstraelen et al. (European Heart Journal, 2021): left ventricular ejection fraction (LVEF; model parameterized per 1% decrease), 24-hour premature ventricular contraction (PVC) count (log-transformed), number of lead

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PM Dependency Index Calculator

PM Dependency Index: Explanation and Clinical Context The Pacemaker (PM) Dependency Index (PDI) is a quantitative tool used to estimate the degree of a patient’s reliance on ventricular pacing. It integrates intrinsic heart rate, ventricular pacing percentage, and atrioventricular block severity to provide a composite score. A higher PDI indicates greater pacemaker dependency, which can guide clinicians in device pro

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Pneumonia Severity Index PSI Calculator

Pneumonia Severity Index PSI Explanation and Clinical Context The PSI is a clinical prediction rule that estimates mortality risk in adults with community acquired pneumonia. It integrates demographic factors comorbid conditions physical findings and laboratory and radiographic data. The total score categorizes patients into five risk groups that correspond to increasing severity and mortality. It assists clinicians

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Polygenic Risk Score (PRS) for Coronary Artery Disease (CAD-PRS) Calculator

Polygenic Risk Score (PRS) for Coronary Artery Disease (CAD-PRS): Explanation and Clinical Context The CAD-PRS quantifies an individual's genetic predisposition to coronary artery disease by summing the weighted effects of multiple single nucleotide polymorphisms (SNPs) identified from genome-wide association studies (GWAS). Each risk allele contributes a specific weight based on its effect size derived from large-sc

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Population Lp(a) Screening Benefit Estimator

This tool estimates the potential population-level yield and benefit of one-time Lp(a) screening. It uses inputs for population size, expected prevalence above a chosen threshold, baseline 10-year ASCVD risk, the relative risk associated with elevated Lp(a), and assumed therapy uptake and relative risk reduction. Notes: Prevalence of Lp(a) ≥125 nmol/L (≈50 mg/dL) is ~20% in many populations; adjust for your local epi

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Porto-Systemic Flow Ratio (PSFR) Calculator

Porto-Systemic Flow Ratio (PSFR): Explanation and Clinical Context The Porto-Systemic Flow Ratio (PSFR) quantifies the relative blood flow between the portal vein and the hepatic vein, reflecting the balance of portal and systemic circulation in patients with chronic liver disease and portal hypertension. A PSFR near 1 indicates a normal physiologic balance, whereas deviations may reflect shunting, hepatic congestion

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POSSUM and P POSSUM Mortality Score Calculator

Physiological Age Cardiac Signs Respiratory History Systolic Blood Pressure Pulse Rate Glasgow Coma Scale Hemoglobin White Cell Count Serum Urea Serum Sodium Serum Potassium Electrocardiogram Score Operative Severity Number of Procedures Blood Loss Peritoneal Contamination Presence of Malignancy POSSUM and P POSSUM Mortality Score Explanation and Clinical Context POSSUM Physiological and Operative Severity Score for

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Post ACS Secondary Prevention Optimization Tool

Post acute coronary syndrome secondary prevention optimisation tool explanation and clinical context This tool is designed to support a structured review of long term therapy in patients who have recently experienced an acute coronary syndrome event. The twenty twenty five acute coronary syndrome guideline emphasises that risk of recurrent events remains elevated for months to years after the index presentation and t

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Post Cardiac Arrest STEMI Prognostic Scoring Tool

Explanation and Clinical Context This score is designed for patients resuscitated from cardiac arrest presenting with ST elevation myocardial infarction who achieve return of spontaneous circulation. Early prognostic insight provides clinical value in guiding revascularization timing and post arrest intensive care strategy including ventilation sedation temperature target management and hemodynamic support. Factors i

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Post PCI Antiplatelet Strategy Selection Tool

Explanation and Clinical Context This tool is designed as a structured aid for clinicians who individualize antiplatelet strategy after percutaneous coronary intervention in the setting of acute coronary syndromes. Current professional guidelines emphasize that duration and intensity of antiplatelet therapy after PCI are determined by a balance between ischemic risk related to the coronary event and stent characteris

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Post-acute Myocarditis Persistent Inflammation Score (MRI + Biomarkers) Calculator

Post-acute Myocarditis Persistent Inflammation Score (MRI + Biomarkers): Explanation and Clinical Context This calculator provides a pragmatic, literature-informed composite score to estimate the likelihood of persistent myocardial inflammation after an acute myocarditis episode using follow-up cardiovascular magnetic resonance (CMR) features and blood biomarkers. It weights factors consistently linked with adverse o

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Post-Cardiac Rehabilitation Risk Reduction Score Calculator

Post-Cardiac Rehabilitation Risk Reduction Score: Explanation and Clinical Context The Post-Cardiac Rehabilitation Risk Reduction Score (PCRRRS) is a clinical tool designed to assess the potential risk reduction in patients with cardiovascular disease who participate in cardiac rehabilitation (CR). Studies have shown that CR is associated with a 20% to 30% reduction in mortality in individuals with coronary artery di

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Post-COVID Arrhythmia Risk Model (Autonomic + ECG) Calculator

Post-COVID Arrhythmia Risk Model (Autonomic + ECG): Explanation and Clinical Context This model integrates autonomic markers (HRV indices) and ECG variables to estimate post-acute arrhythmic risk in individuals recovering from COVID-19. Reduced HRV (low SDNN, RMSSD) reflects sympathetic predominance and vagal withdrawal, patterns observed in post-COVID dysautonomia. QTc prolongation captures impaired repolarization r

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Post-COVID Cardiac Symptom Burden Score (Composite) Calculator

Post-COVID Cardiac Symptom Burden Score (Composite): Explanation and Clinical Context This calculator provides a pragmatic composite symptom burden score focused on cardiovascular manifestations reported after SARS-CoV-2 infection. It aggregates nine domains commonly described in post-acute COVID-19 cohorts: dyspnea (rest and exertion), chest pain/pressure, palpitations, dizziness/presyncope, orthostatic intolerance,

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Post-COVID Microvascular Dysfunction Index (Stress Perfusion Surrogate) Calculator

Quantitative CMR Perfusion Inputs (preferred) Enter global myocardial blood flow (MBF) from quantitative CMR perfusion mapping. Post-COVID Microvascular Dysfunction (Stress Perfusion Surrogate): Explanation and Clinical Context This calculator estimates microvascular function using quantitative stress perfusion metrics. The primary output is myocardial perfusion reserve (MPR), computed from global stress and rest myo

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Post-COVID Thrombotic Risk Composite (D-dimer + Clinical) Calculator

Post-COVID Thrombotic Risk Composite (D-dimer + Clinical): Explanation and Clinical Context This calculator applies the IMPROVE-DD model, combining clinical factors with D-dimer elevation (≥2× ULN) to estimate venous thromboembolism (VTE) risk in post-COVID patients. Clinical Significance: High scores identify patients who may benefit from extended prophylaxis with rivaroxaban 10 mg daily for 35 days post-discharge (

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Post-infectious Autoimmune Cardiac Risk Index (Autoantibodies Panel)

: Explanation and Clinical Context Post-infectious autoimmune cardiac disorders represent a spectrum of myocardial and endocardial injury that follows infectious triggers such as viral myocarditis, bacterial infections, or systemic inflammatory responses. The immune system, after pathogen clearance, may continue to recognize cardiac antigens as foreign due to molecular mimicry between microbial epitopes and myocardia

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Posterior STEMI ECG V7 V9 Diagnostic Tool

clinical explanation Posterior myocardial infarction represents involvement of the basal inferolateral left ventricular wall usually supplied by the circumflex artery. Standard twelve lead ECG often underdetects this pattern because posterior injury current produces reciprocal ST depression in V1 V3 instead of direct elevation. For this reason posterior leads V7 V9 are recommended when posterior infarction is suspect

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Postoperative AKI Cardiac Surgery (AKICS) Calculator

Postoperative AKI after Cardiac Surgery (AKICS): Explanation and Clinical Context The AKICS score is a bedside tool derived and prospectively validated to predict acute kidney injury (AKI) after elective cardiac surgery. It integrates preoperative, intraoperative, and early postoperative information available at ICU admission: combined surgery (e.g., CABG plus valve), NYHA class ≥ 2, pre-operative serum creatinine >

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Postoperative Atrial Fibrillation (POAF) Risk Score Calculator

Postoperative Atrial Fibrillation (POAF) Risk Score: Explanation and Clinical Context The Postoperative Atrial Fibrillation (POAF) Risk Score, developed by Mariscalco and colleagues, provides a simple, evidence-based model to estimate the likelihood of new-onset atrial fibrillation after cardiac surgery. The score incorporates nine routinely available preoperative clinical variables: age, sex, chronic obstructive pul

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Postoperative Delirium Cardiac Risk Score (Rudolph et al.) Calculator

Geriatric Depression Scale – 5 item (GDS-5) History of Stroke or Transient Ischemic Attack Select... Yes No Serum Albumin (g/dL) Abnormal is defined as <3.5 or >5.2 g/dL in the original rule. Postoperative Delirium Cardiac Risk Score (Rudolph et al., 2009): Explanation and Clinical Context This pre-operative rule was derived and validated in older adults undergoing cardiac surgery and assigns points for cognitive imp

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Postoperative Stroke Risk Model (Noncardiac Surgery) Calculator

Postoperative Stroke Risk Model: Explanation and Clinical Context This calculator estimates 30-day postoperative ischemic stroke risk after noncardiac, nonneurologic surgery using preoperative variables. Predictors are derived from NSQIP-based studies and include age, prior stroke/TIA, coronary disease, recent myocardial infarction, renal dysfunction, anemia, dysnatremia, COPD, hypertension, smoking, ASA class, emerg

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Postpartum Hemodynamic Stress Index (PHSI) Calculator

Postpartum Hemodynamic Stress Index (PHSI): Explanation and Clinical Context The Postpartum Hemodynamic Stress Index (PHSI) is a validated metric to assess cardiovascular stress in the early postpartum period, reflecting the balance between heart rate and mean arterial pressure. It is calculated using the formula: PHSI = (Heart Rate / Mean Arterial Pressure) × 100. Mean Arterial Pressure (MAP) is derived from: MAP =

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Postprandial Triglyceride Peak Risk Index Calculator

Postprandial Triglyceride Peak Risk Index: Explanation and Clinical Context Postprandial triglyceride (TG) elevation reflects the body’s ability to metabolize dietary fats after meals. Normally, plasma TG peaks within 3–4 hours postprandially and returns to baseline within 6–8 hours. A delayed TG peak, often observed in individuals with insulin resistance, obesity, or metabolic syndrome, is an early marker of endothe

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Potassium Requirement Calculator

Potassium Requirement: Comprehensive Explanation and Clinical Context The estimation of potassium requirement is an important component of clinical decision making for patients with hypokalemia. Potassium is the predominant intracellular cation and plays a key role in membrane potential regulation, cardiac electrophysiology, skeletal muscle contraction, and acid base homeostasis. Serum potassium does not reflect tota

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PPE Cardiac Risk (AHA 14-Element) Calculator

Preparticipation Physical Evaluation (PPE) Cardiac Screening: Explanation and Clinical Context This calculator implements the American Heart Association (AHA) 14-element cardiovascular screening checklist used during the PPE to identify athletes at risk for congenital or genetic heart disease associated with sudden cardiac arrest or death. It aggregates the 10 history items and 4 focused examination items, providing

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PPV and NPV Post Test Probability Calculator

Explanation and Clinical Context This calculator estimates the positive predictive value and negative predictive value of a diagnostic test by integrating sensitivity specificity and pretest probability. These metrics help clinicians understand how likely a patient either truly has or truly does not have a disease after receiving a positive or negative test result. Positive Predictive Value PPV expresses the probabil

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Pre-eclampsia Cardiovascular Risk Index (PE-CRI) Calculator

Pre-eclampsia Cardiovascular Risk Index (PE-CRI): Explanation and Clinical Context The PE-CRI is a predictive model designed to estimate the long-term cardiovascular risk in women with a history of pre-eclampsia. It incorporates factors such as age, body mass index (BMI), blood pressure, and previous pre-eclampsia history to calculate a risk score. This tool aids clinicians in identifying individuals at higher risk f

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Pre-op Hemodynamic Optimization Index (PHOI) Calculator

Pre-op Hemodynamic Optimization Index (PHOI): Rationale, Use, and Evidence The PHOI provided here is a pragmatic composite to help clinicians summarize the patient’s immediate pre-operative hemodynamic state and identify modifiable targets before anesthesia induction. It is not a published or validated score; to our knowledge there is no original “Pre-op Hemodynamic Optimization Index” in the literature. The componen

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Pre-participation Screening ECG Abnormality Score (International Criteria)

: Explanation and Clinical Context The International Criteria provide a systematic approach to differentiate physiological, training-related ECG changes from patterns suggestive of cardiac pathology in athletes aged roughly 12–35 years. Borderline findings (left/right axis deviation, left/right atrial enlargement, and complete right bundle branch block) are common variants; a single borderline finding in isolation do

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PRECISE-DAPT Score Calculator

PRECISE DAPT Score Clinical Explanation and Context The PRECISE DAPT Score is a validated clinical tool designed to estimate bleeding risk in patients undergoing dual antiplatelet therapy following percutaneous coronary intervention. The score includes age, hemoglobin, white blood cell count, creatinine clearance, and history of prior bleeding, which together reflect hematologic status, renal function, and vulnerabil

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Predict Score Calculator (In-Hospital Mortality in Infective Endocarditis)

Predict Score: Explanation and Clinical Context The Predict Score is a clinical tool designed to estimate the risk of in-hospital mortality in patients with infective endocarditis. Developed through a retrospective analysis of 530 patients, this score incorporates various clinical and laboratory parameters to stratify patients into low, intermediate, or high-risk categories.

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PREDICT-HF Risk Calculator

PREDICT-HF Risk Score: Explanation and Clinical Context The PREDICT-HF model (PARADIGM Risk of Events and Death in Contemporary Treatment of Heart Failure) was derived in patients enrolled in the PARADIGM‑HF trial (n ≈ 8,011) with chronic heart failure with reduced ejection fraction, and was subsequently validated in the ATMOSPHERE trial population and in the Swedish Heart Failure Registry (SwedeHF). Key baseline pre

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Pregnancy Due Date and Estimated Delivery Date Calculator

Explanation and Clinical Context This calculator estimates the expected delivery time using the Last Menstrual Period date as reference. Gestation is assumed as forty weeks or two hundred eighty days from LMP which is widely used in clinical obstetrics. This approach supports counselling and follow up planning for fetal growth monitoring and maternal evaluation. Normal pregnancy duration may vary in clinical reality

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Pregnancy Risk Algorithm Calculator

Pregnancy Risk Algorithm: Explanation and Clinical Context The Pregnancy Risk Algorithm is a clinical tool designed to assess the risk of adverse pregnancy outcomes based on maternal characteristics and medical history. By evaluating factors such as maternal age, body mass index (BMI), presence of chronic hypertension, history of preeclampsia, and family history of preeclampsia, healthcare providers can stratify pati

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Primary Aldosteronism Cardiovascular Trait Score (PACT Score) Calculator

Primary Aldosteronism Cardiovascular Trait (PACT) Score: Explanation and Clinical Context The PACT Score is designed to quantify the cardiovascular risk in patients suspected of primary aldosteronism, integrating key clinical and biochemical traits such as blood pressure, serum potassium, plasma aldosterone concentration, and plasma renin activity. It calculates the Aldosterone-to-Renin Ratio (ARR) and assigns weight

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Procalcitonin Cardiac Sepsis Index (PCSI) Calculator

Procalcitonin Cardiac Sepsis Index (PCSI): Explanation and Clinical Context The Procalcitonin Cardiac Sepsis Index (PCSI) is a novel composite score designed to stratify risk in patients with suspected cardiac sepsis. It integrates three critical parameters: serum procalcitonin (PCT), a marker of systemic bacterial infection; NT-proBNP, an indicator of cardiac stress; and the Sequential Organ Failure Assessment (SOFA

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PROCAM Risk Score Calculator

Explanation: The PROCAM (Prospective Cardiovascular Münster) Risk Score estimates the 10-year risk of acute coronary events, such as myocardial infarction or sudden cardiac death, in adults without established cardiovascular disease. It incorporates key metabolic and lifestyle factors—age, LDL, HDL, triglycerides, systolic blood pressure, smoking, diabetes, and family history—to generate a personalized risk profile.

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Prognostic Nutritional Index (PNI) Calculator

Prognostic Nutritional Index (PNI): Explanation and Clinical Context Prognostic Nutritional Index (PNI) is a clinical tool used to assess the nutritional and immunological status of patients, originally developed by Onodera et al. in 1984. It is calculated using serum albumin concentration and total lymphocyte count. PNI has been validated as a predictor of postoperative complications, surgical outcomes, and prognosi