Uno H, Cai T, Pencina MJ, D'Agostino RB, and Wei LJ. On the C-Statistics for Evaluating Overall Adequacy of Risk Prediction Procedures with Censored Survival Data. Statistics in Medicine. 2011;30:1105-117.
R contributed package survC1 (example) C-statistics for risk prediction models with censored survival data (Hajime Uno)
SAS version of survC1 contributed by Brian Starr