Author/Editor		Andersen Kragh, Per; Pohar Perme, Maja; Houwelingen, Hans C.; Cook, Richard John; Joly, Pierre; Martinussen, Torben; Taylor, Jeremy M. G.; Abrahamowicz, Michal; Therneau, Terry M.
Title		Analysis of time-to-event for observational studies
Type		članek
Publication year		2020
Volume		str. str.
ISSN		0277-6715 - Statistics in medicine
Language		eng
Abstract		This paper provides guidance for researchers with some mathematical back- ground on the conduct of time-to-event analysis in observational studies based on intensity (hazard) models. Discussions of basic concepts like time axis, event definition and censoring are given. Hazard models are introduced, with special emphasis on the Cox proportional hazards regression model. We provide check lists that may be useful both when fitting the model and assessing its goodness of fit and when interpreting the results. Special attention is paid to how to avoid problems with immortal time bias by introducing time-dependent covariates. We discuss prediction based on hazard models and difficulties when attempt- ing to draw proper causal conclusions from such models. Finally, we present a series of examples where the methods and check lists are exemplified. Com- putational details and implementation using the freely available R software are documented in Supplementary Material. The paper was prepared as part of the STRATOS initiative.
Keywords		Cox regression mode survival analysis multistate model Coxov regresijski model analiza preživetja večdržavni model