# Construction and validation of a prognostic model across several studies, with an application in superficial bladder cancer

@article{Royston2004ConstructionAV, title={Construction and validation of a prognostic model across several studies, with an application in superficial bladder cancer}, author={Patrick Royston and Mahesh K B Parmar and Richard J. Sylvester}, journal={Statistics in Medicine}, year={2004}, volume={23} }

Many models for clinical prediction (prognosis or diagnosis) are published in the medical literature every year but few such models find their way into clinical practice. The reason may be that since in most cases models have not been validated in independent data, they lack generality and/or credibility. In this paper we consider the situation in which several compatible, independent data sets relating to a given disease with a time‐to‐event endpoint are available for analysis. The aim is to…

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