Caprini Score (VTE Risk, 2005)

Calculate the CHA₂DS₂-VASc score to stratify stroke risk in non-valvular atrial fibrillation and guide oral anticoagulation. Components: Congestive heart failure/LV dysfunction (+1), Hypertension (+1), Age ≥75 (+2), Diabetes (+1), prior Stroke/TIA/thromboembolism (+2), Vascular disease — prior MI/PAD/aortic plaque (+1), Age 65–74 (+1), Sex category female (+1). Range 0–9 (women) / 0–8 (men). Thresholds: men ≥2 or women ≥3 → recommend oral anticoagulation (DOAC preferred over warfarin); men 1 or women 2 → consider anticoagulation; men 0 or women ≤1 → omit. Female sex alone is not an independent risk factor (score 1 from sex alone is treated as 0). Includes an approximate annual stroke-risk estimate (Lip 2010 derivation cohort). Derived from Lip 2010 (Chest), 2019 AHA/ACC/HRS update, and 2023 ACC/AHA/ACCP/HRS AF guideline. Combine with bleeding risk (HAS-BLED) and shared decision-making. Not medical advice.

Calculate the Charlson Comorbidity Index (CCI), including the age-adjusted variant, to predict 1-year mortality from chronic comorbidities. 19 comorbidities are weighted by mortality risk: 1 point (MI, CHF, PVD, cerebrovascular disease, dementia, chronic pulmonary disease, connective tissue disease, peptic ulcer, mild liver disease, diabetes without complications); 2 points (hemiplegia/paraplegia, moderate-to-severe CKD, diabetes with end-organ damage, any non-metastatic tumor, leukemia, lymphoma); 3 points (moderate-to-severe liver disease); 6 points (metastatic solid tumor, AIDS). Age adjustment adds 1 point per decade ≥50 (50-59 +1 … ≥90 +5). Interpretation: 0 ~8%, 1-2 ~25%, 3-4 ~50%, ≥5 ~80-90% 1-year mortality (derivation cohort). Derived from Charlson 1987 (J Chronic Dis) and the 1994 validation. Not medical advice.

Compare three pneumonia severity scores side-by-side from one set of inputs to support concordance reading. CURB-65 (0-5: Confusion, Urea, RR, BP, age ≥65) — quick bedside triage; PSI/PORT (Fine 1997, 5 risk classes) — the most accurate mortality stratification, more complex; SMART-COP (0-10, 2 points each for SBP <90 and hypoxia, 1 point each for multilobar CXR, albumin <3.5, RR ≥25, tachycardia ≥125, confusion, pH <7.35) — predicts need for ICU respiratory/vasopressor support. Each score has a different focus: CURB-65 is fast; PSI is more precise; SMART-COP identifies who needs ICU. The tool reports each score's total/category/interpretation and an agreement analysis (whether all three point to outpatient/admission/ICU). When scores disagree, favor the more conservative disposition. Derived from Lim 2003, Fine 1997, Charles 2008. Not medical advice.

Calculate the drug accumulation index R under repeated fixed-interval dosing with linear first-order elimination: R = 1 / (1 - e^(-kτ)), where k = ln2 / t½ and τ is the dosing interval. R is the ratio of the steady-state peak concentration to the peak concentration after the first dose — it quantifies how much the body burden rises at steady state versus a single dose. For example, dosing once per half-life (τ = t½) gives R = 2. The term e^(-kτ) is the fraction of peak concentration remaining at the end of one interval. Valid only for linear first-order elimination with fixed dose and interval — NOT for Michaelis-Menten drugs (phenytoin) or non-linear kinetics. Not medical advice.