Fitting Cox Model Using PROC PHREG and Beyond in SAS
نویسندگان
چکیده
Cox proportional hazard model has been widely used for survival analysis in many areas in investigating time-to-event data. PROC PHREG in SAS has been a powerful tool used for construction of a Cox model. In addition to the STATEMENTs and OPTIONs within PHREG that have already provided the most demanded output, a little more effort on data manipulation would accomplish the calculations and generate output for some new statistical approaches. This paper presents: 1) Using overall C-index as a measure of discrimination for model validation; 2) Calculating adjusted survival rate using corrected group prognosis method; 3) Presenting the effect of a continuous covariate on estimated survival. The core SAS program code and MACRO used for implementation are included.
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