How to get C statistic from cox regression with time-dependent covariates

Crystal_F — Tue, 08 Sep 2020 23:22:40 GMT

Hi,

I used proc phreg to conduct survival analysis but failed to get the c statistic from the model. I kept receiving an error message from the log: 'Neither concordance nor ROC analysis is performed with the START/STOP specification' .

ods graphics on;
PROC PHREG DATA=temp.POP_long2 concordance plots=roc rocoptions(at=365 to 2920 by 365);
class c_age (ref='1') c_education (ref='1') c_gender (ref='2') c_race (ref='1') 
      c_married(ref='0') c_access(ref='0') c_financialDifficulty(ref='0') c_depression(ref='0')
      c_Anxiety(ref='0') c_demclas(ref='3') c_carecompanion(ref='0') 
      c_ParticipationRestriction(ref='0')/param=reference;
MODEL (start,stop)*flag_visitFallout_t(0)=c_age  c_gender c_race c_education c_married c_access c_financialDifficulty 
                                          c_ParticipationRestriction c_depression c_Anxiety Comorbidities_f  
                                          IADLs c_demclas  c_carecompanion /TIES=EFRON;
RUN

I also tried something like:

plots=auc rocoptions(method=ipcw(cl seed=1234));

but that didn't work neither.

I wonder if there is any way to work around this. Thanks for your inputs!

Re: How to get C statistic from cox regression with time-dependent covariates

pink_poodle — Sat, 19 Sep 2020 00:18:56 GMT

Please check out this example:
https://support.sas.com/kb/63/276.html

topic How to get C statistic from cox regression with time-dependent covariates in Statistical Procedures

How to get C statistic from cox regression with time-dependent covariates

Re: How to get C statistic from cox regression with time-dependent covariates