Fagan Nomogram (post-test probability) — free, runs in your browser
Bedside evidence-based reasoning: pre-test probability × likelihood ratio → post-test probability, from sensitivity/specificity or a directly entered LR… Computed in your browser — no data uploaded.
Open free tool →Runs in your browser
No software installation. Paste your data and get results instantly.
Publication-ready output
Export charts as SVG vector or HD/UHD PNG suitable for journal submission.
Data stays local
Nothing is uploaded. Your patient data never leaves your device.
Common questions
How large should a likelihood ratio be?
There is no single agreed grading; commonly quoted rules of thumb (e.g. LR+ > 10 or LR− < 0.1 change probability substantially, values near 1 barely change it) are indicative only — rely on the calculated post-test probability.
What are the original references?
Fagan TJ. N Engl J Med 1975;293:257. PMID 1143310.
When should I use Fagan Nomogram?
Bedside evidence-based reasoning: pre-test probability × likelihood ratio → post-test probability, from sensitivity/specificity or a directly entered LR, with the classic Fagan nomogram. Shows how much a test can change diagnostic certainty.
Is my data safe?
All calculations run entirely in your browser. No data is sent to any server. You can even use the tool offline after the page loads.
Run Fagan Nomogram now
Bedside evidence-based reasoning: pre-test probability × likelihood ratio → post-test probability, from sensitivity/specificity or a directly entered LR… Computed in your browser — no data uploaded.
Open free tool →Free to use. No account required. No data uploaded.
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