Survival estimates and sample size: what can we conclude?
Attempts to understand aging processes often involve life-span measurements from which a survival curve is constructed and model parameters estimated. The parameter estimates are then compared, and conclusions concerning the underlying biological processes are subsequently deduced, based upon the magnitude of the parameter differences. In this article we discuss the role of sample size and sample fluctuation on the parameter estimates and the profound effect that these factors may play in our arrival at meaningful biological conclusions. We then extend this discussion to examine one methodology that can help select sample sizes for specific parametric survival models.
Shouman
R
R
Department of Applications Research and Development, University of Texas System, USA.
Witten
M
M
D000375:Aging; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D018401:Sample Size; D016019:Survival Analysis