Power analysis and sample-size determination in survival models with the new stpower command
AbstractPower analysis and sample-size determination are important components of a study design. In survival analysis, the power is directly related to the number of events observed in the study. The required sample size is therefore determined by the observed number of events. Survival data are commonly analyzed using the log-rank test or the Cox proportional hazards model. Stata 10’s new stpower command provides sample-size and power calculations for survival studies that use the log-rank test, the Cox proportional hazards model, and the parametric test comparing exponential hazard rates. It reports the number of events that must be observed in the study and accommodates unequal subject allocation between groups, nonuniform subject entry, and exponential losses to follow-up. This talk will demonstrate power, sample-size, and effect-size computations for different methods used to analyze survival data and for designs with recruitment periods and random censoring (administrative and loss to follow-up). It will also discuss building customized tables and producing graphs of power curves.
Download InfoIf you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.
Bibliographic InfoPaper provided by Stata Users Group in its series North American Stata Users' Group Meetings 2007 with number 13.
Date of creation: 31 Aug 2007
Date of revision:
This paper has been announced in the following NEP Reports:
- NEP-ALL-2007-09-09 (All new papers)
- NEP-CDM-2007-09-09 (Collective Decision-Making)
- NEP-DCM-2007-09-09 (Discrete Choice Models)
You can help add them by filling out this form.
reading list or among the top items on IDEAS.Access and download statisticsgeneral information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Christopher F Baum).
If references are entirely missing, you can add them using this form.