useR's, I am trying to do a power calculation for a survival analysis using a logrank test and I need some help properly doing this in R. Here is the information that I know: - I have 2 groups, namely HG and LG - Retrospective analysis with subjects gathered from archival data over 20 years. No new recruitment of subjects and no estimated time to target accrual and accrual rate. - Survival measured in both groups at 1 year, 3 years, 5 years. - Assume 50% survival for LG and 30% survival for HG at 5 years. - Assume a 6 month difference in overall survival to be statistically significant. - Total sample size is ~ N=500 with 15% of subjects comprising the LG group; 85% make up the HG group.
The main hypothesis is that HG group has shorter overall survival than LG group. Can someone please help me out with how to properly calculate the power for such a situation using R? This is new to me. Thanks, D -- View this message in context: http://r.789695.n4.nabble.com/Power-calculation-for-survival-analysis-tp3830031p3830031.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
