Restricted mean survival time
= Restricted mean survival time
{title2=$\operatorname{RMST}(\tau)=\int_0^\tau S(t)\,dt$}
The restricted mean survival time to a fixed cutoff $\tau$ is $\mathbb E[\min(T,\tau)]=\int_0^\tau S(t)\,dt$ for a nonnegative event time. This follows by the <tail integral formula for moments>. Unlike the unrestricted mean, it uses no tail beyond $\tau$; under <independent censoring> it can be estimated by integrating a <Kaplan–Meier estimator> over adequately observed follow-up.