epower: Power and sample size for time-to-event data based on...

View source: R/epower.r

epowerR Documentation

Power and sample size for time-to-event data based on exponential closed form solution

Description

Power is calculated for two-sample studies. Can be vectorized, but w, lam, cens, must always be length 2.

Usage

epower(n, r, alpha = 0.05, w = c(1, 1), n1, n2, lam, cens)

esamsize(r, w = c(1, 1), alpha = 0.05, power = 0.8, lam, cens)

Arguments

n

Total sample size.

r

Effect size (ratio of hazards/medians).

alpha

Type I error rate.

w

Controls sample size balance between two groups. Default: Equal size groups.

n1, n2

Sample size in each group.

lam

Hazard rate in each group (if specified, overrides r).

cens

Censoring rate.

power

Desired power. Default: 0.8.

Examples

epower(30, 2)
epower(30, lam=c(2,1), cens=c(0.2, 0.5))
epower(seq(30, 100, 10), lam=c(2,1), cens=c(0.2, 0.5))
epower(seq(30, 100, 10), w=c(2,1), lam=c(2,1), cens=c(0.2, 0.5))
epower(30, seq(1.5, 2.5, 0.1))
epower(30, 2, alpha=c(0.01, 0.05, 0.1))
esamsize(1.5)
esamsize(lam=c(1.5, 1), cens=1)

pbreheny/breheny documentation built on March 24, 2024, 3:02 p.m.