ssize_D: Sample Size Calculation

In TalhoukLab/biostatUtil: Utility Functions Used in Biostatistics Projects

Sample Size Calculation

Description

Sample size calculation using model-based discrimination measure.

Usage

ssize_D(
  fit,
  D = NULL,
  cens = NULL,
  p = 0.1,
  alpha = 0.05,
  power = 0.8,
  delta = 0.25,
  trial = c("superiority", "non-inferiority")
)

Arguments

fit	an object fit of class coxph
D	discrimination measure D, defaults to output of survival::royston() for fit
cens	censoring proportion, defaults to proportion calculated from fit
p	proportion of D accepted as delta, defaults to 10%.
alpha	Type I error
power	statistical power (1 - Type II error)
delta	superiority/non-inferiority margin. The difference we wish to detect between a prior model and a new model.
trial	either "superiority" or "non-inferiority"

Details

The sample size calculation uses a discrimination measured based on multivariable prognostic time-to-event models.

Value

The final sample size needed in the new model using the supplied input parameters.

Author(s)

Derek Chiu

References

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4603804/

TalhoukLab/biostatUtil documentation built on April 14, 2025, 4:15 a.m.