Sample size estimation for a continuous outcome

Parameters

Significance threeshold (α)	0.025	0.05	0.10	0.20
	One-sided		Two-sided
Power (1 - β)	0.975	0.95	0.90	0.80
Standard deviation of the primary outcome (σ)
You may enter multiple values, delimited by commas or spaces.
Minimal clinically important difference (δ)
Mean in the intervention group mean in the control group. You may enter multiple values, delimited by commas or spaces.

Reference

Campbell MJ, Julious SA, Altman DG. Estimating sample sizes for binary, ordered categorical, and continuous outcomes in two group comparisons. BMJ 1995;311:1145-8. In a new window

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