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Clinical sample-size calculator
Equal two-arm designs. Uses standard normal quantiles (α 0.05 → 1.96, α 0.01 → 2.58; 80% power → 0.84, 90% → 1.28). Dropout and clustering are not included.
n per arm (completers)
63
Total randomized ≈ 126 before dropout. Inflate for loss-to-follow-up in the SAP.
Educational only. Not medical advice, not a regulatory determination, and not a substitute for qualified RA/QA, legal, clinical, or statistical counsel. Clinical sample-size calculator does not submit to FDA, Notified Bodies, or IRBs.
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