Prediction-Model Sample Size (Riley) — free, runs in your browser
Minimum sample size to develop a clinical prediction model (binary): Riley 2019 three criteria (shrinkage S=0.9, Nagelkerke R² difference ≤0.05, outcome… 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?
Riley RD, et al. Stat Med 2019;38:1276-1296. PMID 30357870; TRIPOD+AI. BMJ 2024;385:e078378. PMID 38626948.
When should I use Prediction-Model Sample Size?
Minimum sample size to develop a clinical prediction model (binary): Riley 2019 three criteria (shrinkage S=0.9, Nagelkerke R² difference ≤0.05, outcome-risk precision), taking the maximum; gives required n, events and events-per-parameter (EPP). …
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 Prediction-Model Sample Size now
Minimum sample size to develop a clinical prediction model (binary): Riley 2019 three criteria (shrinkage S=0.9, Nagelkerke R² difference ≤0.05, outcome… Computed in your browser — no data uploaded.
Open free tool →Free to use. No account required. No data uploaded.
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