Advanced Sample Size (Survival/Diagnostic/Non-inferiority) — free, runs in your browser
Sample size for specialized designs: survival studies (log-rank/Cox, Schoenfeld events needed), diagnostic tests (by target sensitivity/specificity prec… 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
What are the original references?
Schoenfeld DA. Biometrics 1983;39:499-503. PMID 6354290; Buderer NM. Acad Emerg Med 1996;3:895-900. PMID 8870764.
When should I use Advanced Sample Size?
Sample size for specialized designs: survival studies (log-rank/Cox, Schoenfeld events needed), diagnostic tests (by target sensitivity/specificity precision), and non-inferiority/equivalence trials (means or rates). For plain means/rates/correlat…
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 Advanced Sample Size now
Sample size for specialized designs: survival studies (log-rank/Cox, Schoenfeld events needed), diagnostic tests (by target sensitivity/specificity prec… Computed in your browser — no data uploaded.
Open free tool →Free to use. No account required. No data uploaded.
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