Sample size calculation for the Comparison of Survival Curves Between Two Groups under the Cox Proportional-Hazards Model for clinical trials.
power to detect the magnitude of the hazard ratio as small as that specified by RR.
ratio of participants in group E (experimental group) compared to group C (control group).
probability of failure in group E (experimental group) over the maximum time period of the study (t years).
probability of failure in group C (control group) over the maximum time period of the study (t years).
postulated hazard ratio.
type I error rate.
Freedman, L.S. (1982). Tables of the number of patients required in clinical trials using the log-rank test. Statistics in Medicine. 1: 121-129
Rosner B. (2006). Fundamentals of Biostatistics. (6-th edition). Thomson Brooks/Cole.